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https://www.dsprelated.com/freebooks/sasp/Gaussian_Window_Transform.html | ## Gaussian Window and Transform
The Gaussian bell curve'' is possibly the only smooth, nonzero function, known in closed form, that transforms to itself.4.15
(4.55)
It also achieves the minimum time-bandwidth product
(4.56)
when width'' is defined as the square root of its second central moment. For even functions ,
(4.57)
Since the true Gaussian function has infinite duration, in practice we must window it with some usual finite window, or truncate it.
Depalle [58] suggests using a triangular window raised to some power for this purpose, which preserves the absence of side lobes for sufficiently large . It also preserves non-negativity of the transform.
### Matlab for the Gaussian Window
In matlab, w = gausswin(M,alpha) returns a length window with parameter where is defined, as in Harris [101], so that the window shape is invariant with respect to window length :
function [w] = gausswin(M,alpha)
n = -(M-1)/2 : (M-1)/2;
w = exp((-1/2) * (alpha * n/((M-1)/2)) .^ 2)';
An implementation in terms of unnormalized standard deviation (sigma in samples) is as follows:
function [w] = gaussianwin(M,sigma)
n= -(M-1)/2 : (M-1)/2;
w = exp(-n .* n / (2 * sigma * sigma))';
In this case, sigma would normally be specified as a fraction of the window length (sigma = M/8 in the sample below).
Note that, on a dB scale, Gaussians are quadratic. This means that parabolic interpolation of a sampled Gaussian transform is exact. This can be a useful fact to remember when estimating sinusoidal peak frequencies in spectra. For example, one suggested implication is that, for typical windows, quadratic interpolation of spectral peaks may be more accurate on a log-magnitude scale (e.g., dB) than on a linear magnitude scale (this has been observed empirically for a variety of cases).
### Gaussian Window and Transform
Figure 3.36 shows an example length Gaussian window and its transform. The sigma parameter was set to so that simple truncation of the Gaussian yields a side-lobe level better than dB. Also overlaid on the window transform is a parabola; we see that the main lobe is well fit by the parabola until the side lobes begin. Since the transform of a Gaussian is a Gaussian (exactly), the side lobes are entirely caused by truncating the window.
More properties and applications of the Gaussian function can be found in Appendix D.
### Exact Discrete Gaussian Window
It can be shown [44] that
(4.58)
where is the time index, and is the frequency index for a length (even) normalized DFT (DFT divided by ). In other words, the Normalized DFT (NDFT) of this particular sampled Gaussian pulse is exactly the complex-conjugate of the same Gaussian pulse. (The proof is nontrivial.)
Next Section:
Optimized Windows
Previous Section:
Dolph-Chebyshev Window | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8808462619781494, "perplexity": 1843.439941133138}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232259316.74/warc/CC-MAIN-20190526145334-20190526171334-00544.warc.gz"} |
https://p-hunermund.com/2015/03/18/beware-of-trolls-part-2/ | Beware of Trolls (Part 2)
Read the first part of this post, with an introduction into the business model of patent trolls, here!
Let’s get into the economics. Think of two companies, call them “Pear” and “Samson”, who are both active in the smart phone business and each making a profit of $\pi_P = \pi_S = \pi$. But in their production process both firms risk to infringe a patent held by a troll with probability $\theta$. Choi and Gerlach assume that when a troll files a law suit and actually wins in court, he can extract a licensing fee of $\pi/2$, which results from bargaining with symmetric bargaining power (Nash solution).
First, consider the case when the troll is dealing with one firm in isolation. If he faces a litigation cost of $L$, he has a credible threat to go to court if
$\theta \frac{\pi}{2} > L$.
In words, the probability to win an infringement litigation times the money a troll can gain has to be higher than the costs of litigation. Otherwise the business is just not profitable for the troll and firms could ignore the letters in their mailbox as cheap talk. If the litigation threat is credible, however, the firm and the troll decide to settle out of court in order to save litigation costs (assuming that both the plaintiff and the defendant pay costs when a case goes to court).
But what happens when Pear and Samson produce very similar phones? If a court were to find that Pear is infringing on a troll’s patent, Samson is very likely to infringe as well. This can be conceptualized by a correlation coefficient in litigation outcomes of $\rho$. In the most extreme case of perfect correlation ($\rho=1$), the troll can extract royalty payments from both firms with (essentially) a single law suit. He then has a credible threat to litigate in twice as many cases
$\theta \frac{2*\pi}{2} > L$.
Now, let’s consider the case of imperfect correlation. Then, even if Pear wins in court against a troll (i.e., the infringement case is dropped), Samson can still not be sure that it isn’t infringing itself. But since Samson knows the correlation of litigation outcomes $\rho$, a dropped case against Pear still bears information. Technically speaking, Samson does a Bayesian updating of its beliefs. If Pear doesn’t infringe the troll’s patent, then Samson’s probability to infringe is equal to
$(1 - \rho) \theta$
which is smaller than $\theta$. This captures the information externality which arises in repeated litigation.
Who benefits from this information externality, the operating firms or the troll? Interestingly, it goes both ways. Assume a sequential game; the troll starts with Pear and afterwards deals with Samson. The model is solved backwards. In the first case, assume that litigation costs are so high that the troll would not have a credible threat against Samson in isolation
$L > \theta \frac{\pi_S}{2}$.
But if the troll wins against Pear in court, updated infringement probabilities would make the threat credible (remember, if Pear infringes its more likely for Samson to infringe as well, leaving the troll with a higher probability to win). In this case, the information externality is in favor of the troll. The troll is more likely to litigate Pear because he might benefit from the litigation outcome when dealing with Samson. Pear foresees that the odds are not in its favor and settles early.
The story changes when litigation costs are low and the troll would, seen in isolation, always want to litigate against Samson (the second firm he visits), i.e.,
$L < \theta \frac{\pi_S}{2}$.
The odds of a litigation of Pear are now in favor of Samson because if Pear survives in court, the troll could lose the credible threat against Samson. Thus, the troll now has something to lose in litigation, namely his credibility against Samson. Whereas, in isolation (without information externalities), the troll would always be credible. Again, Pear foresees the troll’s risk of losing credibility and is now willing to settle in fewer cases.
That’s a pretty cool result, in my view. In the case of bottom-feeder trolls (remember part 1 of this post), who target small firms, litigation costs should be quite high compared to the money that can be made from settlement. The above model predicts that the possibility to target several firms sequentially allows the troll to settle more easily and thus collecting more money from small businesses — making the problem even worse. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 13, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5465946793556213, "perplexity": 3127.4824715594577}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593655891640.22/warc/CC-MAIN-20200707013816-20200707043816-00545.warc.gz"} |
http://ijpam.eu/contents/2011-66-3/index.html | # Contents IJPAM: Volume 66, No. 3 (2011)
C.L. Penninger, A. Tovar, L.T. Watson, J.E. Renaud
KKT CONDITIONS SATISFIED USING
AUTOMATA FOR TOPOLOGY OPTIMIZATION ... 245
M. Duchon
A HELLY TYPE THEOREM IN THE SETTING OF
BANACH SPACES ... 263
Z. Xiao-Kang
RESEARCH AND APPLICATION ON ARTIFICIAL
NEURAL NETWORK ALGORITHMS IN DATA MINING ... 275
ON THE HESSIAN OF THE EXPONENTIAL FUNCTION
WITH VARIABLES ... 287
H. Gingold
COMPACTIFICATION APPLIED TO
A DISCRETE COMPETEING SYSTEM MODEL ... 297
D.-M. Zhu, W.-K. Ching
A NOTE ON THE STATIONARY PROPERTY OF
HIGH-DIMENSIONAL MARKOV CHAIN MODELS ... 321
Y. Xi, C. Luo
ONE KIND OF OPTIMAL CONTROL PROBLEM OF
PORTFOLIO AND CONSUMPTION CHOICE
WITH POWER UTILITY FUNCTION ... 331 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8626700639724731, "perplexity": 22943.701524576703}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-43/segments/1508187823255.12/warc/CC-MAIN-20171019065335-20171019085335-00339.warc.gz"} |
http://mathoverflow.net/questions/47807/on-existence-of-matrices-x-y-s-t-xay-is-diagonal-over-non-commutative-ring | # on existence of matrices X, Y s.t. XAY is diagonal over non-commutative ring
Given $A\in Mat_{n\times n}(R)$ where $R$ is a non-commutative associative ring are there exist any (non-zero) matrices $X, Y\in Mat_{n\times n}(R)$ such that $XAY=diag(a_1, \ldots , a_n)$ for some $a_i$? The interesting answer for me is if $A=(x_{i,j})$ and $R=\mathbb Z [x_{i,j}]$ (free associative non-commutative algebra on $x_{i,j}$ over $\mathbb Z$).
For example if $R$ is commutative then we put $X=Id$, $Y=(det(A_{i,j}))$ and get $XAY=det A\cdot Id$. What about non-commutative polynomials?
Upd1: I want to have a non-commutative polynomial equality. Also I want $X$ and $Y$ to be in general invertible.
Upd2: Ok, I've understood that Update1 wasn't correct. I'm interested in having such matrices over $R=Mat_{m\times m}(A)$ where $A$ is a commutative ring with $1$.
-
If the ring has a unity, then it is easy: just choose $a_{ij} \neq 0$ then $$e_{1i}Ae_{j1}=a_{ij}e_{11}$$ where $e_{kl}$ is the matrix with $1$ in the $(k,l)$ entry and zero elsewhere. If the ring does have $1$, the statement is not generally true, since you can define $xy=0$ for all $x,y \in R$. – Keivan Karai Nov 30 '10 at 17:11
You want $X$ and $Y$ invertible or at least non-zero divisors. Otherwise the answer is no for obvious reasons. – Andreas Thom Nov 30 '10 at 19:12
@Andreas: I want to have a generalization of the equality: $A A^{V}=det A\cdot Id$. – zroslav Nov 30 '10 at 19:31
Take $X=Y=E_{1,1}$ (the matrix unit). Then $XAY=x_{1,1}E_{1,1}$, a diagonal matrix. If $R$ does not have 1, take $X=Y=aE_{1,1}$ for any $a\ne 0\in R$. Then $XAY=ax_{1,1}aE_{1,1}$ (it may be a zero matrix, but zero matrix is diagonal).
Update. Since you now want to find invertible $X,Y$, I would recommend starting with $2\times 2$-matrices and reading the book by Cohn, "Free rings and their relations", especially Chapter 2, Section 2.6.
I've understood that if $R=Mat_n(K)$ then for every $A\in Mat_m(R)$ exist $B\in Mat_m(R)$, s.t. $AB=\lambda Id$. $A=(a_{ij,kl})$ is a $mn\times mn$-matrix over $K$ and $B=A^{V}$ is a $m\times m$-matrix over $R$. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9279824495315552, "perplexity": 211.22107209069767}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-07/segments/1454701161718.0/warc/CC-MAIN-20160205193921-00161-ip-10-236-182-209.ec2.internal.warc.gz"} |
https://www.vistrails.org/index.php?title=User:Tohline/SSC/Structure/PowerLawDensity&diff=5163&oldid=5162 | # Power-Law Density Distributions
Here we begin with the same second-order, one-dimensional ODE that governs the structure of polytropic spheres, namely, the
Lane-Emden Equation
$\frac{1}{\xi^2} \frac{d}{d\xi}\biggl( \xi^2 \frac{d\Theta_H}{d\xi} \biggr) = - \Theta_H^n$ ,
and examine whether or not this governing relation can be satisfied by a power-law enthalpy distribution of the form,
$\Theta_H = A \xi^{-\alpha} ,$
where $A$ and $\alpha$ are assumed to be constants. We note, up front, that such a solution will not satisfy the boundary conditions that are imposed on polytropic spheres. But the simplistic form of a power-law solution can nevertheless sometimes be instructive.
## Derivation
Plugging the power-law expression for the dimensionless enthalpy into both sides of the Lane-Emden equation gives,
$-\alpha (1 -\alpha) A \xi^{-(2 +\alpha)} = - A^n \xi^{-\alpha n} . $
Hence, the power-law enthalpy distribution works as long as,
$\alpha = \frac{2}{n-1} ~~~~~~\mathrm{and}~~~~~~ A = [\alpha (1 -\alpha)]^{1/(n-1)} = \biggl[ \frac{2(n-3)}{(n-1)^2} \biggr]^{1/(n-1)}.$
This means that hydrostatic balance can be established at all radial positions within a spherically symmetric configuration for power-law density distributions of the form,
$\frac{\rho}{\rho_c} = \biggl[ \frac{2(n-3)}{(n-1)^2} \biggr]^{n/(n-1)} \xi^{- 2n/(n-1)}.$
(Note that, in this case, the subscript c should not represent the central conditions but, rather, conditions at some characteristic radial position within the configuration.)
## Examples
It looks like the derived solution makes some physical sense only for polytropic indices $n > 3$. For $n=4$, the relevant power-law density distribution is,
$\frac{\rho}{\rho_c} = \biggl[ \frac{2}{9} \biggr]^{4/3} \xi^{- 8/3}.$
For $n=(3+\epsilon)$ and $\epsilon \ll 1$,
$\frac{\rho}{\rho_c} \approx \biggl[ \frac{\epsilon}{2} \biggr] \xi^{- 3}.$
For $n \gg 1$,
$\frac{\rho}{\rho_c} \approx \biggl[ \frac{2}{n} \biggr] \xi^{- 2}.$
Hence, for polytropic indices in the range $\infty > n > 3$, the relevant power-law density distribution lies between $\rho \propto \xi^{-2}$ and $\rho \propto \xi^{-3}$.
## Isothermal Equation of State
Suppose the gas is isothermal so that the relevant equation of state is,
$P = c_s^2 \rho ,$
where $c_s$ is the sound speed. To determine what power-law density distribution will satisfy hydrostatic equilibrium in this case, it is better to return to the original statement of hydrostatic balance for spherically symmetric configurations,
$\frac{1}{\rho} \frac{dP}{dr} = -\frac{d\Phi}{dr} .$
Plugging in the isothermal equation of state and assuming a radial density distribution of the form,
$\rho(r) = \rho_0 \biggl( \frac{r}{r_0} \biggr)^{-\beta} ,$
we obtain,
$\frac{d\Phi}{dr} = \beta \biggl(\frac{c_s^2}{r}\biggr) .$
Therefore, the Poisson equation gives,
$\frac{1}{r^2}\frac{d}{dr}\biggl[r^2 \frac{d\Phi}{dr}\biggr] = \beta \biggl(\frac{c_s^2}{r^2}\biggr)= 4\pi G \rho_0 \biggl( \frac{r}{r_0} \biggr)^{-\beta} .$
This relation can be satisfied only if,
$\beta = 2 ~~~~~\mathrm{and}~~~~~ \rho_0 = \frac{c_s^2}{2\pi G r_0^2} .$
Hence, hydrostatic balance can be achieved for an isothermal gas with a power-law density distribution of the form, $\rho \propto r^{-2}$. Because an isothermal $P(\rho)$ equation of state is obtained by setting $n = \infty$ in the more general polytropic equation of state, the result just derived is consistent with the above, more general analysis which showed that, for values of the polytropic index $n \gg 1$, the equilibrium power-law density distribution tends toward a $\rho \propto r^{-2}$ distribution.
# Related Wikipedia Discussions
© 2014 - 2021 by Joel E. Tohline | H_Book Home | YouTube | Appendices: | Equations | Variables | References | Ramblings | Images | myphys.lsu | ADS | Recommended citation: Tohline, Joel E. (2021), The Structure, Stability, & Dynamics of Self-Gravitating Fluids, a (MediaWiki-based) Vistrails.org publication, https://www.vistrails.org/index.php/User:Tohline/citation | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9328851103782654, "perplexity": 1505.8026608288926}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882571210.98/warc/CC-MAIN-20220810191850-20220810221850-00077.warc.gz"} |
https://earthscience.stackexchange.com/questions/9690/what-is-the-geologic-origin-of-cryolite-and-could-there-be-more | # What is the geologic origin of Cryolite, and could there be more?
Cryolite is a mineral of aluminum (Na$_3$AlF$_6$). The only known natural deposit was found in Ivittuut, Greenland. It was mined from 1854 to 1987 and yielded 3.7 Mt of Cryolite ore.
Basically my question is, why is this the only cryolite deposit known? What is the origin of it and why didn't any more form?
There are a lot of similar islands in the arctic: Canadian islands, Russian islands, Scandinavia and Svalbard, etc. Do geologists believe other Cryolite deposits are out there, just not discovered yet?
Ivigtut Cryolite deposit, Ivittuut (Ivigtut), Arsuk Fjord, Sermersooq, Greenland deposit is the first and largest occurrence of Cryolite but it is not the only location to report Cryolite.
Some of these other locations listed below have produced collectible specimens but cryolite does not occur in large enough quantities to be mined.
Other important locations are: Reference (I have seen specimens from these locations)
• ST PETERS DOME PEGMATITE PROSPECT, Pikes Peak Colorado
• Francon Quarry Mt St Hilaire, QUEBEC
(other listed locations, Reference)
• MONZONITE GROUP, Gunnison County Colorado
• FANNY GOUGE MINE, Yancey Co. North Carolina
• BARINGER HILL MINE, Llano, Texas
• MC GUIRE PIT Marathon Wisconsin.
• Also reported from near Miass, Russia.
I also suspect there are other Canadian locations but Canada publishes less mineral data than the United States does.
Cryolite occurs in syenite vein deposits (igneous rock which is quartz deficient) which had abundant amounts of fluorine.
There are 13 other known mineral specimens that contain primarily: Na, Al, F. Cryolite is the most common mineral, due entirely to the Ivigtut deposit. The geologic conditions at the Ivigtut deposit led to deposition of cryolite instead of an other mineral phase containing Na, Al, and F.
I believe additional deposits with cryolite may be found in the future but the Greenland deposit is likely to remain the first and most important deposit. There are a handful of completely unique ore deposits on earth, Ivigtut Cryolite deposit is one of them.
See zincite from Franklin New Jersey as another example where a specific mineral was only ever commerically mined from a singular location.
• Barringer peaked my interest, so I've just looked it up in "Texas Through Time" by Thomas Ewing (publ end of 2016). This doesn't mention cryolite, but the Barringer Hill pegmatite is mentioned. Discovered 1887. Mined for REEs, especially Gadolinite. Described as a "rich" deposit (for REEs). Now submerged beneath Lake Buchanan. – winwaed Feb 14 '17 at 18:03 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3584868609905243, "perplexity": 14715.691384742313}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-30/segments/1563195523840.34/warc/CC-MAIN-20190715175205-20190715200248-00047.warc.gz"} |
https://stats.stackexchange.com/questions/78854/multiple-linear-regression-question | # Multiple linear regression question
I am running a multiple regression of the form Y = $\beta_0$ + $\beta_1$*$X_1$ + $\beta_2$*$X^2_1$ + $\beta_3$*$X_2$ + $\beta_4$*$X_3$ on a time-series dataset. I want to plot the relationship between Y and $X_1$ based on this equation such that I get a curve after taking into account the effects of $X_2$ and $X_3$ (or in other words, after the effects of $X_2$ and $X_3$ are removed from Y). What is the most appropriate way to do this?
You can plot the predicted value of Y from the equation at various levels of $X_1$, but you have to choose values of $X_2$ and $X_3$ for those lines. One choice would be the median value of each.
• Thanks for the quick response, Peter. Just to add, time here is the year of data collection. I want to understand how Y changes just as a function $X_1$ in one part of the analysis (given the two other IVs), whereas in a second and separate analysis with a much larger dataset, I want to see how Y changed over time with $X_1$, $X_2$, and $X_3$ as independent variables, may be, with the variable 'time' as a classification variable. My objective in the first case is to plot Y vs. $X_1$ (given the two other IVs), and in the second case to is to see the progression of Y over time. – Kris Dec 7 '13 at 15:10
• You can see Y as a function of $X_1$ by doing what I suggested. But, as I said, this will give a false picture if both variables are increasing or decreasing over time; any two variables that are linked to time will be linked to each other (e.g. attendance at NFL games and the value of the Dow Jones Industrial average). – Peter Flom Dec 7 '13 at 15:13
• That is what we want to know, how Y changes as a function of $X_1$ (e.g. whether Y decreases/increases as $X_1$ decreases/increases, after the effects of two other IVs are taken into account). The relationship of Y and $X_1$, with time, is not linear. – Kris Dec 7 '13 at 15:36
• As long as both Y and $X_1$ have any relationship with time, any graph or equation that does not account for time will be misleading. – Peter Flom Dec 7 '13 at 16:16
• If there is any trend of Y and $X_1$ with time, then what would be best thing to do? Include time T as one of the independent variables in the regression equation to account for this? Thanks for your time. – Kris Dec 7 '13 at 16:43 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.38457098603248596, "perplexity": 267.3417332232691}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986703625.46/warc/CC-MAIN-20191020053545-20191020081045-00060.warc.gz"} |
http://www.physicsforums.com/showthread.php?p=3890020 | # Law Of Restitution And Momentum
by ZxcvbnM2000
Tags: momentum, restitution
P: 64 let's assume that there are two ball of identical mass and one of the two is stationary . and the collision is NOT head on . I know that the law of restitution always applies ONLY to the line of impact of two bodies .What about momentum , is it conserved in both the line of impact AND the line perpendicular to it ? I am asking because i feel like the law of restitution is similar to momentum conservation so i feel like applying it "twice". Is momentum conserved in all axes regardless of whether 0≤e≤1 ? Thank you !
Related Discussions General Physics 4 Classical Physics 2 Introductory Physics Homework 15 Introductory Physics Homework 0 General Physics 1 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9142135381698608, "perplexity": 461.34758873607313}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1398223210034.18/warc/CC-MAIN-20140423032010-00250-ip-10-147-4-33.ec2.internal.warc.gz"} |
https://torpille.ch/en/hydroelectricity-western-switzerland/ | # ⚡ Hydro-electricity in French-Speaking Switzerland in 2020
## Foreword
### Article purpose
The purpose of this article is to present the different aspects of hydropower, i. e. electricity production with the power of water, within the regional framework of French-speaking or Western Switzerland without forgetting international focuses.
### Electricity
Electricity, an energy carrier, has revolutionized the way machines operate since the early 1900s, it is now an integral part of our daily lives and it is no longer conceivable to do without it.
Electricity can be produced by many energy sources such as solar, wind, water or nuclear. Currently, the vast majority of electricity in Switzerland is generated by nuclear (38%) and hydropower (57%), while worldwide, it is clearly fossil fuels (oil, gas, coal). Solar (1.2% in Switzerland) and wind (0.1% in Switzerland) are encouraging but remain far behind for the moment in terms of electricity production.
The world’s largest wind farm in Gansu, China. Its total power should reach 20 GW in 2020 (Grande Dixence 2 GW). Photo Flickr Tim Zachernuk.
A solar farm in Ukraine. Photo Flickr “Activ Solar”.
### Dams
In the case of dams, we are of course dealing with hydropower where electricity is produced by the force of water that drives a turbine (see below for types of turbines). It is one of the oldest techniques for producing electricity on a large scale. The higher the flow rate and speed of the water, the greater the force or quantity of water on the turbine and therefore the better the electricity production. To increase the speed, the greatest difference in height between a reservoir and the turbine is needed, this is where the dam that retains the highest possible amount of water at altitude comes in. The maximum flow rate is obtained by turbining the water of a river, in this case the speed will be low but we will benefit from the high flow rate.
In Switzerland, hydroelectric power plants are either run-of-river, storage (dams) or pumped storage power plants. Run-of-river and storage power plants produce the same amount of electricity annually in Switzerland (each 17,000 GWh) but storage power plants have a much higher capacity than run-of-river plants, 8,000 MW compared to 3500 MW. Indeed, storage power plants operate less constantly and more at the time of peak consumption. Pumped storage power plants (see below) produce 1300 GWh/year for a capacity of 1500 MW are expected to expand. The above figures are provided by the Swiss Federal Office of Energy (SFOE), which is in charge of monitoring dams in Switzerland and concerns power plants of more than 0.3 MW. It should be noted that smaller installations can be useful as if they turbined “free of charge” the excess pressure of a drinking water supply installation.
The Verbois dam turbining the waters of the Rhône with its run-of-river plant. Built in 1944 after 5 years of work, the dam is inaugurated in the presence of General Guisan.
The Mauvoisin dam holding back the water in order to be turbined by power plants.
Les sites suivants sont intéressants pour obtenir plus d’informations:
### What are the benefits of hydropower?
Hydroelectricity is often considered as “green” energy, i.e. its energy source, water, is recyclable and does not emit harmful emissions such as CO2 (coal) or radioactive waste (nuclear). Solar and wind energy are also considered “green” but have the disadvantage of being linked to weather conditions. However, it would be wrong to say that hydropower does not emit greenhouse gases because dam reservoirs contain microorganisms that break down organic substances and produce CO2 and methane. A paragraph discusses this aspect below.
Another little-known advantage of electricity produced with the water from a dam is the possibility of strongly modulating its injection into the grid according to needs and in particular at times of peak consumption, which is particularly useful because electricity is still not storable in large quantities nowadays. The famous Bieudron power station near Sion in Valais allows to mobilize its 1200 MW power from stop to full power in less than 3 minutes to produce peak energy. A nuclear or run-of-river power plant will be designed to produce electricity in a constant way, ensuring the “background noise” of the consumption or ribbon energy.
### What are the disadvantages of hydropower?
The main disadvantages of hydropower are its impact on the environment. A dam, particularly at the level of a river, will impoverish biodiversity by, for example, cutting off water circulation for fish. High mountain dams dry up streams that disturb the ecosystem. The construction of a dam can affect the population by forcing them to move and cause landslides in newly flooded areas.
Fortunately, in Switzerland, dams are mainly built outside residential areas and reasonably affect the environment, although dams on the Saane River in Schieffenen and Rossens significantly disturb the ecosystem. Indeed, Schieffenen and Rossens, in addition to having swallowed up agricultural land and forced people to leave their village, cut off the circulation of fish, which is not the case in Mauvoisin and Grande Dixence.
For the anecdote, Atlantic salmons went up the Rhine, the Aare and then the Saane to breed in Gruyère until the end of the 19th century. This is no longer the case for several reasons:
• The dams and obstacles along the river block traffic.
• The artificial lakes preventing fish orientation because there is no longer a current of water.
• The housing destruction and the degradation of water quality.
However, in 2013, thanks to efforts in Germany, salmon were spotted in Rheinfelden on the Rhine near Basel showing their reappearance in Switzerland since 1950 as an indicator of the good health of a river. Nevertheless, the return of salmon to Gruyère is problematic and because it involves crossing two dams (Schieffenen and Rossens) nearly 80 metres high.
#### Ecological aspects
In other countries, ecological considerations are still not taken into account as little as for the dam of all the superlatives, the Three Gorges Dam in China, which has forced one and a half million people to move and swallowed up a considerable amount of arable land. Some species have even disappeared like a river dolphin specimen. A significant increase in the number of small earthquakes has been observed since the dam was impounded and even worse, some believe that the earthquake of 12 May 2008, causing 87,000 victims, was caused by the mass of the dam supporting a seismic fault. Moreover, this mass is such, about 50 billion tons, that it has modified the distribution of the Earth’s mass in relation to its axis of rotation and has lengthened the rotation time by 0.06 microseconds.
#### Boats traffic
Dams on rivers also have the disadvantage of hindering boat traffic. To overcome the problem, locks are being installed to overcome the obstacle. At the Trois-Gorges dam (again him!), the difference in height is so great (more than 100 m) that “monstrous” boat lifts are in service rather than locks. They lift the boats and the water that allow them to float.
Schieffenen dam.
Moiry dam.
#### The Itaipu Dam
Concerning the Itaipu dam on the border between Brazil and Paraguay, its impoundment has caused the disappearance of a natural wonder, the Seven Falls Waterfall. Until 1982, when it disappeared, it was the largest waterfall in the world in terms of water flow at more than 10,000 m³/s. By way of comparison, the Rhine Falls in Switzerland have an average start of about 350 m³/s. The Seven Falls Waterfall is even irremediably destroyed by the former Brazilian military regime in power by blasting its parts that remained above the water to facilitate navigation on the reservoir created by the dam. The electrical infrastructure linked to this dam is the second most powerful in the world clearly behind that of the Trois-Gorges, but the annual electricity produced is equivalent between the two infrastructures to around 100 TWh.
The Itaipu dam. Photo Flickr Myben.be
The Itaipu dam. Wikimedia.org.
#### The Aswan Dam
The case of the monstrous Aswan dam on the Nile is interesting. This huge weight dam is built to produce energy but also to prevent floods and mitigate droughts. Its dimensions are impressive with a volume of 42 million m³ of soil and rockfill, a crown length of 3800 m, a width at the base of the dam of nearly one kilometre and a water retention of 169 billion m³. All these figures are much higher than those of the Three Gorges dam, but at the same time the Aswan dam produces much less electricity, its power (2 GW) and its annual electricity production (8 TWh) are 10x lower than those of the Three Gorges.
Unfortunately, the negative consequences on the environment of this dam built in the middle of the Cold War with the help of the Soviet Union are many. In addition to the engulfment of historic monuments or the greater reflux of salt water onto the Nile, the most interesting case is the retention by the dam of the fertilizing silt that has allowed the growth of crops on the Nile plain for millennia. This results in the use of fertilizers by farmers. Another phenomenon caused by the dam is the modification of streams at the Suez Canal, which increases the intrusion of the Red Sea fauna, often intrusive, into the Mediterranean fauna. Some experts question the usefulness of this dam (and even large dams in general), considering that the disadvantages outweigh the advantages it brings.
The downstream side of the D’Assouan dam in the middle of the desert. Photo Flickr J. Griffin Stewart.
#### Le dégagement de méthane
Finally, a last and little-known disadvantage is the release of methane gas, a greenhouse gas much more powerful than CO2, through the reservoirs. The organic material in the water is broken down in the oxygen-poor layers by bacteria that convert it into methane and CO2. The release of methane depends on several factors such as the amount of organic matter, the water temperature or the depth of the reservoir.
The actual methane emissions figures from dams are still unclear and subject to discussion, but it would appear that Alpine dams are not very affected by these emissions, unlike those located in the tropics or on the equator at low altitude. Some figures indicate that dams in these latter regions would emit up to nearly 20% of the methane associated with human activities, which would mean that dams are not as “clean” as often described while other studies tend towards opposite values with more symbolic figures in relation to methane release.
## Types of energy
The energy in the dam is stored as potential energy. When it flows from the dam as water in the penstock, it gains speed and is transformed into kinetic energy. A turbine converts kinetic energy into mechanical energy and then the latter is in turn converted into electrical energy by an alternator that operates in the opposite direction to the turbine. Electricity flows into high-voltage lines using a transformer.
The problem with electricity is that it cannot be directly stored in large quantities despite decades of research. This is where the advantage of the dam that stores this electricity indirectly comes in with the accumulation of water as potential energy. A pumped storage station, such as the one at the Emosson dam in Nant de Drance, allows water to be turbined during periods of high consumption and therefore produce electricity and, on the contrary, during periods of low consumption, to be stored by pumping it between two water reservoirs at different altitudes.
In the case of the Nant de Drance, the water is pumped up from the Emosson dam to the Vieux-Emosson dam 300 metres higher. Pumped storage makes it possible to “transform” electricity into potential energy, the efficiency is around 80%, which means that for every 100 units of energy used to pump up water, 80 will be produced. It should be noted that the price of the energy used to raise water is often much lower than the price that can be sold with the turbine because we will ensure that electricity is produced when demand is high.
Nikola Tesla (1856-1943). Born in Croatia during the time of the Austrian Empire, he emigrated to the United States and developed the first alternators for alternating current electricity production. Today, Tesla’s name is known as an electric car manufacturer.
### Summary
Dam = Potential Energy → Penstock = Kinetic Energy → Turbine = Mechanical Energy → Alternator = Electricity
## Dams
Discover all the details about the dams in Western Switzerland in the very complete article of la Torpille.
The magnificent Grande Dixence dam. This is one of the 12 largest dams in French-speaking Switzerland presented in the article written by la Torpille.
## Power plants
### Power of hydroelectricity
Surprisingly, by far the most electricity-producing installations in the world are hydroelectric complexes. The installation of the Trois-Gorges dam with a capacity of 22,500 MW and an annual production of 100,000 GWh is by far the most important. The most powerful nuclear power plant is located in Canada with a capacity of 6300 MW and an annual production of 45’000 GWh. The Kashiwazaki-Kariwa nuclear power plant in Japan has a capacity of 8,300 MW but has been shut down since the 2011 earthquake as a precautionary measure and has still not restarted. Many power plants produce electricity with other means but are less powerful than hydropower or nuclear power.
The Kashiwazaki-Kariwa nuclear power plant by the Sea of Japan before its partial destruction. Flickr photo from “IAEA Imagebank”.
### Nuclear power plants in Switzerland
Concerning Switzerland, the Leibstadt power plant built in 1984 is the most powerful of the 5 nuclear power plants built in Switzerland. Its capacity is 1200 MW for a production of 10,000 GWh per year. The Beznau I nuclear power plant is the oldest operating power plant in the world. On 21 May 2017, the Swiss people decided to ban the construction of new nuclear power plants on a vote on energy developments.
The Mühleberg nuclear power plant in the canton of Berne built in 1972. It was the least powerful of the five Swiss power stations. It is finally shut down on 20 December 2019. It will take more than 15 years to dismantle it.
### The distribution of electricity production
The Grande-Dixence hydraulic installation, the most powerful in its sector and composed of 3 power plants, is much more powerful than Leibstadt with its 2000 MW (1200 MW for the Bieudron) but produces much less electricity with 2,000 GWh (Bieudron 1700 GWh) annually than the Leibstadt plant.
Indeed, the nuclear power plant operates continuously and almost at full capacity, which is not the case for Grande-Dixence. In Switzerland, the huge majority of electricity is generated by hydropower (58%) and nuclear power (38%). It should be noted that just before the construction of the first Swiss nuclear power plant in 1969, hydropower accounted for 90% of Switzerland’s electricity production.
The most powerful run-of-river power plant turbining water, not by accumulation as in the Bieudron, is the Verbois power plant in the canton of Geneva along the Rhône with 98 MW and an annual production of 466 GWh. A superb map lists the hydropower plants in Switzerland on the website of the Swiss Federal Office of Energy (SFOE).
Storage power plants (dams) and run-of-river power plants each account for 48% of Swiss hydroelectric production, the rest comes from pumped storage.
## Types of turbines
### Introduction
Three types of turbines are mainly used in hydroelectric production. The Kaplan, Francis and Pelton turbines named after their respective inventors at the end of the 19th century and the beginning of the 20th century. No other efficient water turbines have been produced since these dates.
Each turbine is adapted to different environments mainly according to the height of the waterfall and the water flow. The Kaplan and Francis turbines are called “reaction” turbines, i.e. the inlet pressure in the wheel is higher than the outlet pressure, while the Pelton turbine is called “action” turbines, i.e. the inlet and outlet pressure in the wheel is the same. We add here the Deriaz turbine, a very small minority but observed during the visit of the Montsalvens dam.
### Pelton turbine
The Pelton turbine owes its name to its inventor Lester Allan Pelton (1829-1908), an American carpenter by profession. It is the modern version of the paddle wheel used to turn the water of a mill in the Middle Ages and until the beginning of the 20th century. At that time, the water of a river was channeled and brought on a water-taking wheel thanks to wooden shelves called vanes.
Dawn wheels at the Iron and Railway Museum in Vallorbe.
The Pelton turbine operates on the same principle. It is made of an ultra-resistant metal mixture and receives water at very high pressure from one or more injectors on the central edge of buckets resembling two nut shells or buckets allowing water to escape from the sides. This principle was patented by Pelton in the 19th century.
Buckets of a Pelton turbine on display at the Riddes/Econe plant in Valais.
The injection is tangential to the turbine wheel and can be horizontal or vertical using 1 to 6 injectors. Horizontal axis turbines have up to 2 injectors and up to 6 for vertical axis turbines. The kinetic energy of the water is transformed into mechanical energy after turbining and for maximum efficiency, the velocity of the water after injection must be as low as possible, ideally zero.
Allan Pelton in 1880 inventor of the turbine that bears his name.
Large Pelton turbines operate in the vast majority of cases in connection with a dam and a high waterfall to generate power during peak consumption periods. The Bramois power station at the bottom of the Borgne Gorge is an exception since its large Pelton turbines produce electricity “run-of-river” depending on the water flow available. There is no water accumulation before the power station.
It should be noted that Pelton turbines have a slightly lower efficiency than Kaplan and Francis turbines due to their small surface area in contact with water.
The most powerful Pelton turbine in the world is the Bieudron turbine, near Sion in Switzerland. With a diameter of about 5m, it has a capacity of 423 MW and a record waterfall of 1883 metres with the Grande-Dixence dam. The Valais in Switzerland is particularly suitable for the use of Pelton turbines, which are efficient at relatively low flows of less than 20 m3/s and waterfalls of more than 400 metres.
Indeed, the bottom of the valleys lateral to the Rhone Valley is often steeped and at an altitude of more than 1500 metres, allowing the construction of dams. In addition, the lateral valleys are close and particularly high compared to the Rhone Valley itself, at an altitude of less than 500 metres. The power plants built in the Rhône Valley therefore benefit from a significant waterfall with relatively short penstocks.
The aim is to bring the water against the turbine with the highest possible speed. The speed of the water depends only on the height of fall with the formula $v = sqrt{2gh}$ is the Earth’s gravity and varies slightly according to the places on earth and h the height difference. What is the speed of the water arriving from the Grande-Dixence dam on the Bieudron turbine? The height is 1883 m, g is equal to 9.81 m/s. So the square root of 2 x 1883 x 9.81 is equal to 192 m/s, which corresponds to the phenomenal speed of 691 Km/h.
The turbine must therefore be very resistant and that is why it is manufactured by a robot in a single piece of metal. The turbine speed is equal without loss to half the injection speed, i.e. 345 km/h for the Bieudron. For the brief history, gravity varies according to where you are on Earth and is lowest at the equator due to the opposite centrifugal force due to the rotation of the Earth.
What is the rotation frequency of the wheel in rpm at Bieudron? The formula is: 60 x speed (m/s) / wheel diameter (m) x Pi, so 60 x 96 m/s / 4.6m x 3.14 = 398 rpm.
A remarkable document with photos traces the history of the Pelton turbine and its operation, including a drawing of the penstock that brings water to the turbine with the injectors.
#### YouTube videos on the Pelton turbine
Vidéo sur l’ensemble d’un système hydraulique utilisant une roue Pelton.
Reconstitution d’un petit modèle Pelton.
Fabrication par un robot à partir d’un seul pièce de métal d’une roue Pelton.
### Francis turbine
This is the most powerful turbine model. This turbine can produce 700 MW of power, as at the Itaipu dam in Brazil and the Trois-Gorges dam in China, which has a capacity of more than 10 to 50 million dollars each. It is perfectly suited for a large water flow and a waterfall of several hundred meters. For example, the water from the Mauvoisin dam is turbined by the Fionnay plant 400m lower using 3 Francis turbines.
The name of this turbine comes from its inventor James Bicheno Francis. It is an improvement of the turbine designed by Benoit Fourneyron, itself derived from Jean-Victor Poncelet’s invention at the beginning of the 19th century. The Francis turbine was first commissioned in 1848. It is a submerged “reaction” turbine because the pressure at the inlet is greater than that at the outlet and its diameter can reach 10 meters for the largest models.
James Biceno Francis in 1887. Source Wikimedia.
The operating principle is as follows: the water enters all around the turbine thanks to a spiral pipe called a spiral tarpaulin then guided radially towards the wheel and its ten blades or vanes. The guide vanes modulate the power of the turbine by regulating the flow of water to the moving vanes of the wheel and thus making it rotate more or less quickly. The kinetic energy of the water and the energy from the pressure difference are transmitted to the alternator for electricity production. After passing through the turbine wheel, the water is then evacuated axially by the vacuum cleaner. Like Pelton turbines, Francis turbines can operate horizontally or vertically.
Francis turbine in oblique position at the Fionnay plant. It turbined the water from the Mauvoisin dam for 40 years.
Francis turbine at the Mottec plant in the Val d’Anniviers.
The Electrobroc plant with visible blade wear due to cavitation.
### Kaplan turbine
Invented by Viktor Kaplan and first commissioned in 1912, the Kaplan turbine is particularly suitable for high water flow rates and very low waterfall. Like the Francis turbine, it is a submerged turbine called a “reaction” turbine where the pressure at the inlet of the wheel is higher than at its outlet.
This turbine looks like a propeller whose blades can be rotated even when running according to the water flow, which makes it interesting for a river with a variable flow rate. The Kaplan turbine can have a diameter of 10 m and weigh several tens of tons, it is the fastest rotating turbine, up to 1000 rpm. The waters of Lake Schieffenen are the only major dams in French-speaking Switzerland to be turbined at the foot of the dam by two Kaplan turbines with a combined capacity of 70 MW.
Turbine Kaplan. Source Wikimedia.org
Vikto Kaplan. Source Wikimedia.org
Small Kaplan demonstration turbine exposed at Electrobroc.
### Deriaz or Diagonal turbine
This turbine is suitable for small hydropower, its operating range includes flows from 0.1 to 10m3/s and a net drop of about 20 to 80 meters. It operates at the foot of the Montsalvens dam by turbining the waste water from the Jogne river. It is a turbine very similar to the Kaplan turbine in its design and operation is similar to the Francis turbine with diagonal injection of water against the turbine.
Deriaz turbine. Photo: omos.cz
### Summary
TurbinePeltonFrancisKaplanDiagonale or Deriaz
TypeAction turbineReaction turbineReaction turbineReaction turbine
InventorLester Allan Pelton (USA)James Bicheno Francis (USA)Viktor Kaplan (AUT)Paul Deriaz (SUI)
Date1879191818481945
Max. power in service [MW]423
Bieudron (SUI)
715
Itaipu (BRA)
230
?
Max. operating diameter [m]510155
Optimal water flow rate [m3/s]less than 25until 700until 8000.1 à 10 ?
Water height [m]more than 40030 to 300until 3020 to 65
Turbine speed [tour/min]until 36until 400until 1000
UnderwaterNoYesYes
PositioningVertical or horizontalVertical or horizontal?
## Transport of electricity
In Switzerland, electricity is transmitted by SwissGrid, a 450-person company that manages the grid and its maintenance. Interesting statistics are available on the Swissgrid website. This company manages the electricity transmission network, which includes 380 kv very high voltage lines with a length of 1780 km and 220 kv lines with a length of 4920 km. The total number of very high voltage lines is 6700 km for more than 10’000 pylons.
The distribution network includes high (9000 km), medium (45000 km) and low (85000 km) voltage lines. Transformers ensure the conversion between the different intensities. High and very high voltage lines are overwhelmingly overhead, while the opposite is true for medium and low voltage lines, which are mostly underground. The cost of burying a very high voltage line is close to 10x more expensive than an overhead line but provides an improvement in landscape and wildlife as well as a lower vulnerability to bad weather.
It is interesting to note that the loss of electricity during its transport is about 6%. It is reported that Switzerland with SwissGrid imports electricity mainly from France but also from Germany and Austria and exports electricity to Italy.
Pylon and very high voltage lines between the La Bâtiaz substations in Martigny and Châtelard to bring the electricity produced into the Emosson dam infrastructure.
## Future of electricity in Western Switzerland
### Cost of electricity
Energy costs have fallen particularly in recent years, leading to hydroelectricity in French-speaking Switzerland but also in Switzerland and even in Western Europe in an unprecedented crisis. The reasons are as follows:
• Liberalisation of the energy market in Europe.
• Arrival on the market of electricity produced by coal-fired power plants that benefit from the low cost of coal and that of CO2 emissions.
• Solar and wind power generation in neighbouring countries, particularly Germany.
A bulldozer in a plant of Slovenia growing coal originating from Indonesia. Source: Wikimedia Commons
The price per KWh on the European market is around 3-4 cents at the time of purchase, while that produced by hydraulics doubles it, i.e. 6-8 cents per KWh, while it is sold between 10 cents and 40 cents per KWh to the final customer. It is therefore cheaper to import electricity abroad than to produce it in Switzerland, which seriously threatens the profitability of Switzerland’s hydroelectric infrastructure, primarily dams.
The closure of coal-fired power plants at European level and a strong economic recovery could change the situation and cause a price increase on the European market, but the price seems for the moment to remain very low for some time. A large number of new construction projects and especially hydraulic renovations have been cancelled in Switzerland, while recently completed pharaonic projects such as the Veytaux pumped storage plants in Montreux and especially the Nant de Dranse plant next to the Emosson dam risk becoming a financial abyss. At the time of the beginning of the development of these projects, electricity selling prices were much higher than at present and could be expected to generate a real profit.
### Global warming
Currently, global warming is causing an increase in the amount of water available in dams by accelerating the melting of glaciers. It is estimated that by 2050, the situation will be reversed with a significant decrease in the water supply of glaciers due to their gradual disappearance.
Some studies claim that glaciers in Switzerland will have almost completely disappeared by 2100, so the water supply will not only be provided by snowfalls and rainfall, which will insufficiently fill the dams. One solution could come from pumped storage where water is pumped into the dam during periods of low consumption. For example, one could imagine pumping water from the Rhône to fill the Grande-Dixence dam.
## Hydropower in the world
### Largest hydroelectric producers
Not surprisingly, China is the world’s largest hydropower producer with more than a quarter of total production in 2015 1126 TeraWatt/h. Brazil and Canada each produce about 10% of the world total with about 350 to 400 TeraWatt/h in 2015.
The total capacity of Chinese hydroelectric installations is more than 300 GW, including more than 22 GW for the Trois Gorges dam. By way of comparison, the Grande Dixence installations have a power of approximately 2.5 GW. In Switzerland, total hydroelectric production was 40 TeraWatt/h in 2015 for a capacity of 14 GW generated by more than 600 power plants.
### Hydraulics compared to other energy sources
The share of hydropower in the world’s total electricity production is 16% in 2010. The total being 24,097 TW/year for 2,999 TW/year for hydroelectricity. The “large” countries that use hydropower most are Norway almost totally (96%) as well as Brazil, Venezuela and Canada in a percentage between 60% and 70%.
Switzerland comes just after with 58%. 5 “small” countries produce 100% of their energy from dams. These are Albania, Bhutan, Lesotho, Nepal and Paraguay.
### Statistics and videos on dams and hydropower
Video on dams.
A video on the Itaipu dam.
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https://www.hepdata.net/search/?q=cmenergies%3A1.34&page=8 | Showing 10 of 197 results
#### rivet Analysis Summary of experiments with the neutral detector at the e+ e- storage ring VEPP-2M
Dolinsky, S.I. ; Druzhinin, V.P. ; Dubrovin, M.S. ; et al.
Phys.Rept. 202 (1991) 99-170, 1991.
Inspire Record 321108
The complete results of the experiments carried out with the Neutral Detector at the e + e − storage ring VEPP-2M in the energy range 2 E =0.5–1.4 GeV are reviewed. The data sample corresponds to a total integrated luminosity of 19 pb −1 .
16 data tables match query
ND results from Dolinsky et al., PL B174 (1986) 453.. Statistical errors only are shown. There is an additional systematic errorof 8%.
Averaged ND data.. Statistical errors only are shown. There is an additional systematic errorof 8%.
Cross section derived from ARGUS data, Albrecht et al., PL B185 (1987) 223.. Statistical errors only are shown. There is an additional systematic errorof 8%.
More…
#### Proton Polarization in gamma p --> pi0 p Reaction at an Angle of Theta (pi) = 100-Degrees in CMS in the Second pi n Resonance Region
Derebchinsky, A.I. ; Zybalov, A.A ; Konovalov, O.G. ; et al.
Inspire Record 135482
1 data table match query
No description provided.
#### rivet Analysis Study of the Reaction $e^+ e^- \to K^+ K^-$ in the Energy Range 1350 $\le \sqrt{s} \le$ 2400-{MeV}
The collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.
Z.Phys.C 39 (1988) 13, 1988.
Inspire Record 262690
Thee+e−→K+K− cross section has been measured from about 750 events in the energy interval$$1350 \leqq \sqrt s\leqq 2400 MeV$$ with the DM2 detector at DCI. TheK± form factor |FF±| cannot be explained by the ρ, ω, ϕ and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.
1 data table match query
No description provided.
#### Measurement of the Radiative Width of the A(2) (1320) in Two Photon Interactions
The collaboration Althoff, M. ; Braunschweig, W. ; Gerhards, R. ; et al.
Z.Phys.C 31 (1986) 537, 1986.
Inspire Record 228876
The reactione+e−→e+e− A2 (1320) has been observed by detecting the decayA2→π+,π-π0. The two-photon width of theA2 has been measured to be Г(A2→γγ)=(0.09±0.27 (stat)±0.16 (syst)) keV. The cross section σ(γγ→π+,π-π0 has been determined outside theA2 resonance region.
1 data table match query
#### Search for Two Photon Production of Resonances Decaying Into $K \bar{K}$ and $K \bar{K} \pi$
The collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 29 (1985) 189, 1985.
Inspire Record 220941
An analysis of the production ofKS0KS0 andK±Ks0π∓ by two quasi-real photons is presented. The cross section forγγ→K0$$\overline {K^0 }$$, which is given for the γγ invariant mass range fromK$$\bar K$$ threshold to 2.5 GeV, is dominated by thef′(1525) resonance and an enhancement near theK$$\bar K$$ threshold. Upper limits on the product of the two-photon width times the branching ratio intoK$$\bar K$$ pairs are given forΘ(1700),h(2030), and ξ(2220). For exclusive two-photon production ofK±Ks0π∓ no significant signal was observed. Upper limits are given on the cross section ofγγ→K+$$\overline {K^0 }$$π− orK−K0π+ between 1.4 and 3.2 GeV and on the product of the γγ width times the branching ratio into theK$$\bar K$$π final states for theηc(2980) and the ι(1440), yieldingΓ(γγ)→i(1440))·BR(i(1440)→K$$\bar K$$π<2.2 keV at 95% C.L.
1 data table match query
Data read from graph.. Corrected for the angular distribution, which is assumed to be sin(theta)**4 for W > 1.14 GeV and isotropic in the first bin.
#### Positive Pion Photoproduction From Hydrogen at Photon Energies Between 500-{MeV} and 1400-{MeV} in Forward Direction
Althoff, K.H. ; Anton, G. ; Bock, B. ; et al.
Z.Phys.C 18 (1983) 199, 1983.
Inspire Record 189703
The differential cross section of the reactionγ+p→π+ was measured at pion CM-angles of 20° and 30° for photon energies between 500 MeV and 1,400 MeV. The pions were detected in a magnetic spectrometer. By measuring each pion trajectory and by offline calculation of the initial pion parameters an energy resolution of about 2.5% FWHM was achieved. The results complete a set of data which were measured in recent years at the Bonn 2.5 GeV synchrotron. In comparison to photoproduction analyses two effects were revealed: The η cusp appears in the energy dependence of the cross section as a sharp drop atKγ=710 MeV. In the region of the third resonance the data show a greater enhancement than predicted by most of the analyses.
1 data table match query
No description provided.
#### Measurement of the Reaction gamma gamma ---> pi+ pi+ pi- pi- at PETRA
The collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Z.Phys.C 21 (1984) 205, 1984.
Inspire Record 191578
We have determined the cross section for γγ→π+π+π−π− in a way free of assumptions about the relative contributions fromρ0ρ0,ρ02π and 4π (uncorrelated phase space). We find a sharp onset above threshold and a rather high cross section of about 200 nb aroundWγγ=1.5 GeV which consists to about 40% ofρ0ρ0 production with sizeable contributions fromρ02π and 4π (PS). The total cross section as well as theρ0ρ0 content fall rather fast at higher c.m. energies. Attempts to explain this behaviour in terms of production of known resonances are not successful so far. The angular distributions do not show any significant structure pointing to resonance formation in the 4π-system. Only theρ0-meson is observed in the moment analysis. The decay distributions of theρ0 for forward produced rhos are fairly consistent with helicity conservation of the produced rhos in accordance with the VDM picture.
4 data tables match query
No description provided.
RESULTS OF DECOMPOSITION OF THE CROSS SECTION INTO RHO RHO, RHO 2PI, AND 4PI(PHASE SPACE) USING TWO WIDE W BINS. SEE TEXT OF PAPER FOR DISCUSSION OF FITS.
RESULTS OF DECOMPOSITION OF THE CROSS SECTION INTO THE RHO RHO, RHO PI, AND 4PI (PHASE SPACE) USING SMALL W BINS. SEE TEXT OF PAPER FOR DISCUSSION OF FITS.
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#### Some cross-sections for the photo-production of neutral Pi-mesons from hydrogen at energies from 360 to 938 MeV
Dougan, P. ; Kivikas, T. ; Lugner, K. ; et al.
Z.Phys.A 274 (1975) 73-78, 1975.
Inspire Record 1385254
Some cross-sections for the photo-production of ~z~ from hydrogen for pion c.m. angles in the range 60~ ~ are presented. The data have been obtained by measuring proton yields from a hydrogen target, thus permitting separation of single-pion production from the strong background caused by double-pion production. The values, which extend from 360 to 938 MeV, show reasonable agreement with the results of a recent phase-shift analysis
1 data table match query
No description provided.
#### Cross-Sections for the Photoproduction of pi0 Mesons from Hydrogen from 238-MeV to 922-MeV
Dougan, P. ; Ramsay, V. ; Stiefler, W. ;
Z.Phys.A 276 (1976) 155-160, 1976.
Inspire Record 99794
The results of a comprehensive series of measurements of the cross-sections for the photo-production of π0-mesons from hydrogen at pion c.m. angles from 47 to 145 degrees are presented. The minimum and maximum photon energies have been 238 and 922 MeV respectively.
1 data table match query
No description provided.
#### Measurement and Analysis of the Reaction $\gamma \gamma \to \pi^+ \pi^- \pi^+ \pi^-$
The collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 38 (1988) 521, 1988.
Inspire Record 252632
We have measured the cross section of four charged pion production in photon-photon interactions in the invariant mass range 1.0≦Wγγ≦3.2 GeV and up toQ2=16 GeV2. For 1.2 GeV≦Wγγ≦1.7 GeV the process is dominated by ρ0ρ0 production with a rapid rise in cross section around 1.2 GeV, well below the nominal ρ0ρ0 threshold. The observed distributions in the two particle masses and in the production and decay angles are well described by an incoherent sum of the phase-space subprocesses γγ →ρ0ρ0, →ρ0π+π−, and →π+π−π+π−. A spin-parity analysis of the ρ0ρ0 system showsJP=2+ to dominate, although 0+ is also possible forWγγ≦1.4 GeV. Negative partity states are excluded.
4 data tables match query
No description provided.
No description provided.
No description provided.
More… | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9672073721885681, "perplexity": 6601.074179277151}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487643354.47/warc/CC-MAIN-20210618230338-20210619020338-00253.warc.gz"} |
https://www.dissertations.se/about/Physics/ | # Search for dissertations about: "Physics"
Showing result 1 - 5 of 4091 swedish dissertations containing the word Physics.
1. ## 1. Nonlinear Beam Physics
University dissertation from Lund University , Department of physics
Abstract : A condensed treatment of conventional beam physics (both linear and nonlinear) is given for the non-expert; this constitutes a minimum knowhow for constructing simulations of rudimentary beamlines. The criteria for an ideal nonlinear charged-particle simulation algorithm are then presented, leading to the derivation of a symplectic, explicit, Lorentz-covariant integrator. READ MORE
2. ## 2. Searches for Particle Dark Matter Dark stars, dark galaxies, dark halos and global supersymmetric fits
University dissertation from Stockholm : Department of Physics, Stockholm University
Abstract : The identity of dark matter is one of the key outstanding problems in both particle and astrophysics. In this thesis, I describe a number of complementary searches for particle dark matter. READ MORE
3. ## 3. Aspects of Hadron Production in High-Energy Heavy-Ion Physics
University dissertation from Department of Physics, Lund University
Abstract : High-energy heavy-ion collisions provide a unique tool for the study of nuclear matter as a function of temperature and density. WA98 at the CERN SPS recorded data with a 158 A GeV Pb beam on a Pb target in 1996. To cope with the high charged-particle density, a tracking system based on high granularity multi-step avalanche detectors was developed. READ MORE
4. ## 4. Studies of Top Physics Sensitivity and of Pile-Up Effects on Energy Reconstruction in the ATLAS Detector : A Licentiate Thesis About the Treatment of Troublesome $\tau$ and Producing Pulses to Probe Pile-up Problems
University dissertation from Stockholm : Department of Physics, Stockholm University
Abstract : This thesis presents two studies conducted using the ATLAS detectorat the Large Hadron Collider. The first one is a technical study abouthow out-of-time pile-up affects energy reconstruction using the optimalfiltering 2 algorithm in the TILE calorimeter sub detector. The studyis conducted using a pulse simulator software that is also described. READ MORE
5. ## 5. Dosimetric effects of breathing motion in radiotherapy
University dissertation from Lund University, Faculty of Science, Department of Medical Radiation Physics
Abstract : Cirka hälften av alla som drabbas av cancer i Sverige genomgår strålbehandling, där högenergetisk strålning används för att tillintetgöra cancertumören. Inför strålbehandlingen görs en datortomografiundersökning, vilket är en form av röntgenundersökning som ger snittbilder av patienten i tre dimensioner. READ MORE | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8188776969909668, "perplexity": 8678.671198436392}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496665976.26/warc/CC-MAIN-20191113012959-20191113040959-00178.warc.gz"} |
http://link.springer.com/article/10.1007%2Fs00330-013-2793-2 | , Volume 23, Issue 7, pp 1822-1828
Date: 04 May 2013
# Prospectively ECG-triggered sequential dual-source coronary CT angiography in patients with atrial fibrillation: comparison with retrospectively ECG-gated helical CT
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## Abstract
### Objective
To investigate the feasibility of applying prospectively ECG-triggered sequential coronary CT angiography (CCTA) to patients with atrial fibrillation (AF) and evaluate the image quality and radiation dose compared with a retrospectively ECG-gated helical protocol.
### Methods
100 patients with persistent AF were enrolled. Fifty patients were randomly assigned to a prospective protocol and the other patients to a retrospective protocol using a second-generation dual-source CT (DS-CT). Image quality was evaluated using a four-point grading scale (1 = excellent, 2 = good, 3 = moderate, 4 = poor) by two reviewers on a per-segment basis. The coronary artery segments were considered non-diagnostic with a quality score of 4. The radiation dose was evaluated.
### Results
Diagnostic segment rate in the prospective group was 99.4 % (642/646 segments), while that in the retrospective group was 96.5 % (604/626 segments) (P < 0.001). Effective dose was 4.29 ± 1.86 and 11.95 ± 5.34 mSv for each of the two protocols (P < 0.001), which was a 64 % reduction in the radiation dose for prospective sequential imaging compared with retrospective helical imaging.
### Conclusion
In AF patients, prospectively ECG-triggered sequential CCTA is feasible using second-generation DS-CT and can decrease >60 % radiation exposure compared with retrospectively ECG-gated helical imaging while improving diagnostic image quality.
### Key Points
Coronary computed tomographic angiography (CCTA) can be difficult in patients with arrhythmias.
Prospectively ECG-triggered sequential CCTA is feasible in patients with atrial fibrillation.
Prospective sequential imaging can improve quality compared with retrospective analysis.
Prospective sequential imaging decreases radiation exposure by 64 % compared with retrospective mode. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8280034065246582, "perplexity": 13307.547127979602}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-49/segments/1416400379063.15/warc/CC-MAIN-20141119123259-00015-ip-10-235-23-156.ec2.internal.warc.gz"} |
http://math.stackexchange.com/users/34498/stirling?tab=summary | # Stirling
less info
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bio website location age member for 1 year, 9 months seen Apr 6 at 17:48 profile views 5
2 Logarithm inequality for vectors 2 Finite sums of infinite value 2 5 linear equations in 5 unknowns 0 Monty Hall/Bayes' Theorem 0 Variance Formula
# 271 Reputation
+15 Monotonicity of $\ell_{p}$ norm and Holder's inequality +15 Logarithm inequality for vectors +20 Logarithm inequality for vectors +5 Maximizing a convex function
# 4 Questions
3 Monotonicity of $\ell_{p}$ norm and Holder's inequality 3 Logarithm inequality for vectors 3 Maximizing a convex function 3 Regularity Conditions for Constrained Optimization
# 12 Tags
4 linear-algebra × 3 2 sequences-and-series 2 inequality × 3 0 homework × 2 2 logarithms × 2 0 optimization × 2 2 examples-counterexamples 0 probability × 2 2 infinity 0 convex-analysis
# 4 Accounts
TeX - LaTeX 569 rep 18 Mathematics 271 rep 16 Stack Overflow 116 rep 3 Cross Validated 101 rep | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9781508445739746, "perplexity": 5201.908098091436}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1397609532573.41/warc/CC-MAIN-20140416005212-00313-ip-10-147-4-33.ec2.internal.warc.gz"} |
https://infoscience.epfl.ch/record/176835 | ## High Time-Resolved Cardiac Functional Imaging Using Temporal Regularization for Small Animal on a Clinical 3T Scanner
Accurate assessment of mice cardiac function with magnetic resonance imaging is essential for longitudinal studies and for drug development related to cardiovascular diseases. Whereas dedicated small animal MR scanners are not readily available, it would be a great advantage to be able to perform cardiac assessment on clinical systems, in particular, in the context of translational research. However, mouse imaging remains challenging since it requires both high spatial and temporal resolutions, while gradient performances of clinical scanners often limit the reachable parameters. In this study, we propose a new cine sequence, named "interleaved cine," which combines two repetitions of a standard cine sequence shifted in time in order to reach resolution parameters compatible with mice imaging. More precisely, this sequence allows temporal resolution to be reduced to 6.8 ms instead of 13.5 ms initially imposed by the system's hardware. We also propose a two-step denoising algorithm to suppress some artifacts inherent to the new interleaved cine thus allowing an efficient enhancement of the image quality. In particular, we model and suppress the periodic intensity pattern and further denoise the sequence by soft thresholding of the temporal Fourier coefficients. This sequence was successfully validated with mass and function measurements on relevant mice models of cardiovascular diseases.
Published in:
Ieee Transactions On Biomedical Engineering, 59, 929-935
Year:
2012
Keywords:
Laboratories: | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8479310274124146, "perplexity": 1789.012060736037}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257648594.80/warc/CC-MAIN-20180323200519-20180323220519-00115.warc.gz"} |
http://math.stackexchange.com/questions/370566/simple-question-on-factoring-derivatives-with-e | # Simple question on factoring derivatives with “e”
I have a very simple factoring question; I'm doing a calculus problem in which part of the question requires me to factor a derivative. The derivative in question is $e^{-x}tx^{t-1}-e^{-x}x^t$ (the derivative of $\frac{x^t}{e^x})$. I have no problem with finding the derivative, and once the derivative is factored I can easily solve the problem, but I embarrassingly can't figure out how to factor the derivative by hand into the form $-e^{-x}x^{t-1}(x-t)$. I suspect my problem is that I'm running on rote muscle memory of factoring polynomials. I would appreciate a quick walk-through of the hand computations.
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The formatting is a mess -what is $x(t)$ for example? – Thomas Andrews Apr 23 '13 at 17:15
Presumably, you mean $-e^{-x}(x^{t-1})(x-t)$ in the third formula. – Thomas Andrews Apr 23 '13 at 17:17
Starting with $e^{-x}tx^{t-1}-e^{-x}x^t$
you probably definitely proceeded to $e^{-x}(tx^{t-1}-x^t)$
and then maybe you are overlooking that $x^t=x\cdot x^{t-1}$ so that you recognize both terms hold a factor of $x^{t-1}$.
I've seen this kind of blindness before when students struggle to factor things like $x^{1/2}+x^{3/2}$. They sometimes don't immediately see that $x^{1/2}$ is a common factor since $x^{3/2}=x\cdot x^{1/2}$. It's a good thing to be aware of!
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Thank you, this was exactly what I was overlooking. Thanks also to @CameronWilliams for correcting the formatting. – DeusExCinema Apr 24 '13 at 1:16
I prefer using product rule and so I'd rewrite it as $x^te^{-x}$. The derivative of this is $tx^{t-1}e^{-x}-x^te^{-x}$. Both terms have a common factor of $x^{t-1}e^{-x}$ so we can factor that out to get $x^{t-1}e^{-x}(t-x)$. This is as far as it can be factored without further complicating the expression. What seems to be giving you trouble later in the problem? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.887275755405426, "perplexity": 308.9863790798912}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1393999650773/warc/CC-MAIN-20140305060730-00045-ip-10-183-142-35.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/basic-electricity-question.189042/ | Basic Electricity question
1. Oct 4, 2007
JeeebeZ
1. The problem statement, all variables and given/known data
2 120 Volt bulbs (one 40 watt, one 100 watt) are connected to a variable power supply in series in a circuit. Which bulb will light first
2. The attempt at a solution
So, I'm pretty sure its the 40 watt bulb because it uses less current.
B(40) = 0.3333A
B(100) = 0.8333A
Is this correct or... am i just guessing to much?
2. Oct 4, 2007
pooface
It seems logically correct. Yes. Bulbs can light before their maximum current is applied to them though, meaning the bulbs can be dim and not need to reach .333A to start the first one.
3. Oct 5, 2007
Red_Baron
Red_Baron
My initial response is that the current will always be the same everywhere at every instant in a non-reactive series circuit. Therefore you can expect a higher voltage drop across the higher resistance load, which in this case is the lower wattage lamp. I expect the lower wattage lamp to therefore glow well before the higher one shows any incandescence. Also when the voltage has been dialed up all the way, I expect the lower wattage lamp to still (hot cathode resistance at near design consideration) be way ahead of the higher wattage lamp by being near full brightness and a comparitively dim glow from the other. REM: the lower wattage, thus higher resistance lamp is the dominating, thus current controlling load, and it gets the lions share of the voltage. Also the hotter lamp's resistance will have increased more than the colder one, intensifying the difference between the individual voltage drops even more.
Last edited: Oct 5, 2007
Similar Discussions: Basic Electricity question | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8390184640884399, "perplexity": 2222.7493671739194}, "config": {"markdown_headings": false, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886109682.23/warc/CC-MAIN-20170821232346-20170822012346-00198.warc.gz"} |
http://quanteconpy.readthedocs.io/en/latest/tools/estspec.html | # estspec¶
Filename: estspec.py
Authors: Thomas Sargent, John Stachurski
Functions for working with periodograms of scalar data.
quantecon.estspec.ar_periodogram(x, window='hanning', window_len=7)[source]
Compute periodogram from data x, using prewhitening, smoothing and recoloring. The data is fitted to an AR(1) model for prewhitening, and the residuals are used to compute a first-pass periodogram with smoothing. The fitted coefficients are then used for recoloring.
Parameters: x : array_like(float) A flat NumPy array containing the data to smooth window_len : scalar(int), optional An odd integer giving the length of the window. Defaults to 7. window : string A string giving the window type. Possible values are ‘flat’, ‘hanning’, ‘hamming’, ‘bartlett’ or ‘blackman’ w : array_like(float) Fourier frequences at which periodogram is evaluated I_w : array_like(float) Values of periodogram at the Fourier frequences
quantecon.estspec.periodogram(x, window=None, window_len=7)[source]
Computes the periodogram
$I(w) = (1 / n) | sum_{t=0}^{n-1} x_t e^{itw} |^2$
at the Fourier frequences w_j := 2 pi j / n, j = 0, ..., n - 1, using the fast Fourier transform. Only the frequences w_j in [0, pi] and corresponding values I(w_j) are returned. If a window type is given then smoothing is performed.
Parameters: x : array_like(float) A flat NumPy array containing the data to smooth window_len : scalar(int), optional(default=7) An odd integer giving the length of the window. Defaults to 7. window : string A string giving the window type. Possible values are ‘flat’, ‘hanning’, ‘hamming’, ‘bartlett’ or ‘blackman’ w : array_like(float) Fourier frequences at which periodogram is evaluated I_w : array_like(float) Values of periodogram at the Fourier frequences
quantecon.estspec.smooth(x, window_len=7, window='hanning')[source]
Smooth the data in x using convolution with a window of requested size and type.
Parameters: x : array_like(float) A flat NumPy array containing the data to smooth window_len : scalar(int), optional An odd integer giving the length of the window. Defaults to 7. window : string A string giving the window type. Possible values are ‘flat’, ‘hanning’, ‘hamming’, ‘bartlett’ or ‘blackman’ array_like(float) The smoothed values
Notes
Application of the smoothing window at the top and bottom of x is done by reflecting x around these points to extend it sufficiently in each direction. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3233559727668762, "perplexity": 5861.494319233567}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-13/segments/1490218187519.8/warc/CC-MAIN-20170322212947-00258-ip-10-233-31-227.ec2.internal.warc.gz"} |
https://socratic.org/questions/what-is-the-physical-state-of-neon-at-room-temperature | Chemistry
Topics
# What is the physical state of neon at room temperature?
The normal boiling point of neon is $- 246.0$ ""^@C. This exceptionally low boiling point reflects the lack of intermolecular (here interatomic) interactions. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 2, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6211966276168823, "perplexity": 5084.74321884491}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579250606872.19/warc/CC-MAIN-20200122071919-20200122100919-00226.warc.gz"} |
https://www.physicsforums.com/threads/multi-angular-momenta.240194/ | # Multi-angular momenta
1. Jun 13, 2008
### RodB
I have a Q re angular momentum (L) that's causing some heated discussion. A bullet is fired off center toward a rotatable target with an axis from, say, 100m (like a ballistic pendulum). The bullet has a fixed linear momentum and an L that remains constant as it travels toward the target -- Pxr stays constant as R and the angle change in sync.
Now say the shooter's aim is off and the bullet will miss the target a bit. In this case the bullet has the same constant numerical value of linear momentum (with a small change in the vector due to the aim) and a similarly constant L, but this L is numerically different from the first. This means that the bullet can have an angular momentum with a different target separated by distance and angle from the first target (but all in the same fixed unmoving coordinate system), and that this L is different numerically from the first.
The same bullet now has TWO different numerical angular momenta simultaneously. It then follows that the bullet has a simultaneous momenta with MANY (theoretically infinite) "targets". The angular momentum, in this scenario, is not a specific, single, explicit, inherent quality like linear momentum, but rather it is multiple, with each relative to some other object (axis) within the frame. Does anyone agree or disagree? (A rotating body's L is different and seems specific and inherent, but that's not the debate.)
2. Jun 13, 2008
### rohanprabhu
what you want to say is that the 'moment arm' stays constant i.e. the value $r\sin(\theta)$ stays constant.
yes. you are right. But the way you state it is wrong. When we talk about angular momentum, or any moment, be it torque or moment of inertia, we need to specify about which axis we are calculating that moment. This is the reason the moment of Inertia for say, a cylinder is different along different axis. About a definite axis, the angular momentum is always unique and an inherent quality.
However, you would also like to note that since a sphere is symmetric about it's center, for the sphere, the moment of inertia is the same about any axis passing through the center.
Take the case of linear momentum. If an object having mass 'm' and velocity 'v' has momentum $p = mv$. Now, let us say you are moving at a velocity 'v', so, for you as an observer the velocity of the object now is 0 and hence the linear momentum $p = 0$. similarly, depending on the frame of your reference even the linear momentum has different values.
There is no such thing as 'absolute momentum'. It is always relative to the frame of reference you are viewing it from and for all moments, it is relative to the axis you choose.
3. Jun 14, 2008
### RodB
Thanks, rohanprabhu
So, in the same frame linear momentum is fixed (sans any force) and constant no mater how one looks at it. Angular momentum (again in a same frame) of any particular mass is relative to whatever axis one chooses to relate it to. It shouldn't have been that hard! Slap! Slap! As you point out (the obvious ) even singular rotating masses have different Ls depending on which axis one chooses. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.939930260181427, "perplexity": 640.3535350215681}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886104565.76/warc/CC-MAIN-20170818043915-20170818063915-00261.warc.gz"} |
https://tex.stackexchange.com/questions/347096/how-to-use-verb-in-the-main-title-of-a-beamer-presentation | # How to use \verb|…| in the main \title of a beamer presentation?
I know that to use \verb|...| in a beamer presentation you have to add the fragile option to the frame environment.
But if I use \verb|...| in the main \title of \titlepage it gives me the error:
Runaway argument?
guide to \relax \hbox {}#I\catcode \ \active \<let>-command \csname\endcsname
! Paragraph ended before \HyPsd@@ProtectSpacesFi was complete.
\par
l.5 \begin{document}
How can I solve it?
MWE:
\documentclass{beamer}
\title{Quack guide to \verb|\usepackage{tikzducks}|}
\begin{document}
\begin{frame}[fragile=singleslide]
\titlepage
Why this doesn't work\dots
\end{frame}
\begin{frame}[fragile=singleslide]
\dots whereas this \verb|\usepackage{tikzducks}| works?
\end{frame}
\end{document}
• Quack guide to \texttt{\string\usepackage\string{tikzducks\string}}, perhaps – egreg Jan 4 '17 at 17:40
• @egreg Joseph Wright was quicker than you, both his first solution and yours work :) – CarLaTeX Jan 4 '17 at 17:47
• @egreg ...also his second one, only an \end{document} was missing :) – CarLaTeX Jan 4 '17 at 20:47
• Possible duplicate: Verbatim inside a command – Werner Jan 4 '17 at 21:09
As with any other case: you can't use \verb in the argument to \title. There's always a way of writing the text of a \verb out 'in full', here using \{, \} and \textbackslash:
\documentclass{beamer}
\title{Quack guide to \texttt{\textbackslash usepackage\{tikzducks\}}}
\begin{document}
\begin{frame}[fragile=singleslide]
\titlepage
Why this doesn't work\dots
\end{frame}
\begin{frame}[fragile=singleslide]
\dots whereas this \verb|\usepackage{tikzducks}| works?
\end{frame}
\end{document}
One could also use the cprotect package as described in How to put \verb command inside of \textbf{} block?, which would give
\documentclass{beamer}
\usepackage{cprotect}
\cprotect\title{Quack guide to \verb|\usepackage{tikzducks}|}
\begin{document}
\begin{frame}[fragile=singleslide]
\titlepage
Why this doesn't work\dots
\end{frame}
\begin{frame}[fragile=singleslide]
\dots whereas this \verb|\usepackage{tikzducks}| works?
\end{frame}
\end{document}
• Your second solution gives an error... – CarLaTeX Jan 4 '17 at 17:45
• @CarLaTeX I've just run that code exactly as given with the current release of beamer: it should work fine – Joseph Wright Jan 4 '17 at 17:48
• ... but if I use @egreg's solution (given in a comment) can I accept this answer? – CarLaTeX Jan 4 '17 at 21:03
• @CarLaTeX You can ask him to post a separate answer, though it's much the same as my first suggestion (there are various ways to input non-verbatim versions of what you want). – Joseph Wright Jan 4 '17 at 21:04
• Eventually, thinking of it better, I've accepted your answer because the solution with \cprotect` is more generalized. – CarLaTeX Jan 4 '17 at 21:33 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6083958148956299, "perplexity": 5755.318749413375}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575541288287.53/warc/CC-MAIN-20191214174719-20191214202719-00543.warc.gz"} |
https://gamedev.stackexchange.com/questions/84722/how-to-create-soft-icecream-like-particles-with-liquidfun-and-corona | # How to create soft Icecream like particles with Liquidfun and Corona
Currently using the "elastic" flags for particle behavior, which looks decent when it is flowing downwards but when the icecream collects in cup it is too liquidy. Also this gives it a springy bounce which I am not sure how to take out. I am wondering how I should make it thicker more solid along but to stay a bit elastic? Can I change behavior of particle after it is created?
I have tried with a "spring" flag and "viscous" flag but it looks sort of the same.
Demo Clip
Corona/LiquidFun
-- Create Particle System
local particleSystem = physics.newParticleSystem{
filename = _PRT,
radius = 1,
imageRadius = 2
}
offset_x = _C.x + 70
offset_y = _UL.y + 100
-- Paramaters for red particle faucet
local particleParams_red =
{
flags = { "elastic"},
linearVelocityY = -10,
color = { 1, 0, 0.1, 1 },
x = offset_x,
x = offset_x + display.contentWidth * 0.15,
x = offset_x + display.contentWidth * -0.15,
y = offset_y,
lifetime = 60.0,
radius = 5,
}
## 1 Answer
Check out the powder toy: enter link description here
The ice cream you are attempting to create is a lot more like a collection of soft bodies:
See this video for demonstration please.
It doesn't need to be liquidy once it's in the cup. The liquid could be visually in another layer just to simulate the smooth movement of ice-cream pouring down.
The real icecream (that will stay in the cup) does not have to be liquidy going down. You should consider using soft bodies with little bounce and high friction and a small mass. You can use the liquid for the visual effect of pouring and use a lot of possibly blurred tiny soft bodies cause ice-cream is a lot more like sticky sand than liquid and will look when tweaked right, more realistic as such.
Another option if you don't plan to move continue with the physical simulation, is to build the solid shape of the ice-cream programatically by adding mass where the liquid hits. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.22328031063079834, "perplexity": 3088.508178600129}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882570901.18/warc/CC-MAIN-20220809033952-20220809063952-00734.warc.gz"} |
http://aliquote.org/micro/2020-03-27-09-30-46/ | # aliquot
## < a quantity that can be divided into another a whole number of time />
Nice overview of GTD using Org-mode: A guide to my organizational workflow. #emacs | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.15812355279922485, "perplexity": 5160.280611233907}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590347411862.59/warc/CC-MAIN-20200531053947-20200531083947-00447.warc.gz"} |
http://mathhelpforum.com/calculus/176186-arc-length-spiral.html | # Math Help - arc Length of a spiral
1. ## arc Length of a spiral
HI,
I need to find the length of a spiral given by r(t) = pi*(t*cos(pi*t)i - t*sin(pi*t)j +t k) , from t=0 to t=3
I have been given the formula
integral (sqrt(a^2 + b^2*t^2)dt = 1/2*t*sqrt(a^2 + b^2*t^2) + (a^2/2b)*ln(b*t + sqrt(a^2 + b^2*t^2).
I proceeded to find dot product of tangent vectors
r'(t) . r'(t) = (pi*cos(pi*t) - pi^2*tsin(pi*t))^2 + pi^2(pi*t*cos(pi*t) + sin(pi*t)) +pi^2
However, now i have come unstuck, where do i go from here?
I was thinking about letting a^2 = (pi*cos(pi*t) - pi^2*tsin(pi*t))^2,
b^2= (pi*t*cos(pi*t) + sin(pi*t)) +1, t^2=pi^2
then substituting into the formula and solving t=3 and t=0
But i really have no idea where to get the parameters a , b , t from to use in the formula
Any help would be greatly appreciated.
2. Originally Posted by olski1
HI,
I need to find the length of a spiral given by r(t) = pi*(t*cos(pi*t)i - t*sin(pi*t)j +t k) , from t=0 to t=3
I have been given the formula
integral (sqrt(a^2 + b^2*t^2)dt = 1/2*t*sqrt(a^2 + b^2*t^2) + (a^2/2b)*ln(b*t + sqrt(a^2 + b^2*t^2).
I proceeded to find dot product of tangent vectors
r'(t) . r'(t) = (pi*cos(pi*t) - pi^2*tsin(pi*t))^2 + pi^2(pi*t*cos(pi*t) + sin(pi*t)) +pi^2
However, now i have come unstuck, where do i go from here?
I was thinking about letting a^2 = (pi*cos(pi*t) - pi^2*tsin(pi*t))^2,
b^2= (pi*t*cos(pi*t) + sin(pi*t)) +1, t^2=pi^2
then substituting into the formula and solving t=3 and t=0
But i really have no idea where to get the parameters a , b , t from to use in the formula
Any help would be greatly appreciated.
I think you need to check your derivative. I get that
$\mathbf{r}'(t)=\pi[(\cos(\pi t)-t\pi \sin(\pi t))\mathbf{i}+(-\sin(\pi t)-t\pi \cos(\pi t))\mathbf{j}+\mathbf{k}]$
After dotting this with itself and simplifying I get
$\mathbf{r}'(t) \cdot \mathbf{r}'(t)=\pi^2(\pi^2t^2+2)$
So the integral should be
$\displaystyle \pi \int_{0}^{3}\sqrt{\pi^2t^2+2}$
Now use the substitution $\displaystyle t= \frac{\sqrt{2}}{\pi}\sinh(x)$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 4, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9331898093223572, "perplexity": 2086.425086014053}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-18/segments/1430451452451.90/warc/CC-MAIN-20150501033732-00030-ip-10-235-10-82.ec2.internal.warc.gz"} |
https://www.ideals.illinois.edu/handle/2142/4024 | ## Files in this item
FilesDescriptionFormat
application/pdf
ofor99-05.pdf (2MB)
PaperPDF
## Description
Title: A Nonparametric Analysis of the Forward Rate Volatilities Author(s): Pearson, Neil D.; Zhou, Anjun Subject(s): univariate model bivariate model Abstract: Heath, Jarrow, and Morton (1992) present a general framework for modeling the term structure of interest rates which nests most other models as special cases. In their framework, the dynamics of the term structure and the prices of derivative instruments depend only upon the initial term structure and the forward rate volatility functions. Despite their importance, there has been little empirical work studying the forward rate volatility functions. This paper begins to fill this gap by estimating some nonparametric models of the forward rate volatilities. In a univariate model, the form of the forward rate volatility function differs for different maturities, and for some maturities appears not to be a monotonic function of the level of the forward rate. In a bivariate model, a measure of the “slope” of the term structure seems to have an important impact on the volatility. These results differ from the simple models that have been proposed and used in the literature. Issue Date: 1999-10 Publisher: Office for Futures and Options Research, Department of Agricultural Economics, College of Agricultural, Consumer, and Environmental Sciences at the University of Illinois at Urbana-Champaign Series/Report: OFOR Working Paper Series, no. 99-05 Genre: Working / Discussion Paper Type: Text Language: English URI: http://hdl.handle.net/2142/4024 Publication Status: published or submitted for publication Peer Reviewed: not peer reviewed Date Available in IDEALS: 2008-03-17
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http://journal.imm.uran.ru/node/156 | E.A. Konoval’chik, K.V. Kostousov. Symmetrical 2-extensions of the 2-dimensional grid. II ... P. 192-211
The investigation of symmetrical $q$-extensions of a $d$-dimensional cubic grid $\Lambda^{d}$ is of interest both for group theory and for graph theory. For small $d\geq 1$ and $q>1$ (especially for $q=2$), symmetrical $q$-extensions of $\Lambda^{d}$ are of interest for molecular crystallography and some phisycal theories. Earlier V. Trofimov proved that there are only finitely many symmetrical 2-extensions of $\Lambda^{d}$ for any positive integer $d$. This paper is the second and concluding part of our work devoted to the description of all, up to equivalence, realizations of symmetrical 2-extensions of $\Lambda^{2}$ (we show that there are 162 such realizations). In the first part of our work, which was published earlier, we found all, up to equivalence, realizations of symmetrical 2-extensions of $\Lambda^{2}$ such that only the trivial automorphism fixes all blocks of the imprimitivity system (87 realizations). In the present paper, we find the remaining realizations of symmetrical 2-extensions of $\Lambda^{2}$.
Keywords: symmetrical extension of a graph, $d$-dimensional grid.
The paper was received by the Editorial Office on November 12, 2016
Elena Aleksandrovna Konoval’chik, Cand. Sci. (Phys.-Math.), Krasovskii Institute of Mathematics
and Mechanics, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, 620990 Russia;
Nosov Magnitogorsk State Technical University, Magnitogorsk, 455000 Russia,
e-mail: [email protected] .
Kirill Viktorovich Kostousov, Cand. Sci. (Phys.-Math.), Krasovskii Institute of Mathematics and
Mechanics, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, 620990 Russia,
e-mail: [email protected] .
REFERENCES
1. Trofimov V.I. Symmetrical extensions of graphs and some other topics in graph theory related with group theory. Proc. Steklov Inst. Math. (Suppl.). 2012, 279, suppl. 1, pp. 107-112. doi: 10.1134/S0081543812090088.
2. Neganova E.A., Trofimov V.I. Symmetrical extensions of graphs. Izv. Math. 2014, vol. 78, no. 4, pp. 809-835. doi: 10.1070/IM2014v078n04ABEH002707.
3. Trofimov V.I. The finiteness of the number of symmetrical 2-extensions of the $d$-dimensional lattice and similar graphs. Proc. Steklov Inst. Math. (Suppl.). 2014, 285, suppl. 1, pp. 169-182. doi: 10.1134/S0081543814050198.
4. Trofimov V.I. Some remarks on symmetrical extensions of graphs. Proc. Steklov Inst. Math. (Suppl.). 2015, 289, suppl. 1, pp. 199-208. doi: 10.1134/S0081543815050181.
5. Konovalchik E.A., Kostousov K.V. Symmetrical 2-extensions of a 2-dimensional grid. I. Trudy Inst. Mat. Mekh. UrO RAN. 2016, vol. 22, no. 1, pp. 159-179 (in Russian).
6. GAP - Groups, Algorithms, Programming - a System for Computational Discrete Algebra. Ver. 4.5.7: [e-resource]. 2012. Available at: http://www.gap-system.org.
7. Bettina Eick, Franz Gahler, Werner Nickel. GAP package Cryst - Computing with crystallographic groupsCryst, Ver. 4.1, e-resource, 2013. Available at: https://www.gap-system.org/Packages/cryst.html.
8. Bettina Eick, Max Horn, Werner Nickel. GAP package Polycyclic. Ver. 2.11, [e-resource, 2013. Available at: https://www.gap-system.org/Packages/polycyclic.html. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5358514785766602, "perplexity": 4161.259903714962}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232262600.90/warc/CC-MAIN-20190527125825-20190527151825-00090.warc.gz"} |
https://mathsci.kaist.ac.kr/pow/2014/12/ | # Concluding 2014 Fall
Thanks all for participating POW actively. Here’s the list of winners:
• 1st prize (Gold): Park, Minjae (박민재) – 수리과학과 2011학번
• 2nd prize (Silver): Chae, Seok Joo (채석주) – 수리과학과 2013학번
• 3rd prize (Bronze): Lee, Byeonghak (이병학) – 수리과학과 2013학번
• 4th prize: Park, Jimin (박지민) – 전산학과 2012학번
• 5th prize: Park, Hun Min (박훈민) – 수리과학과 2013학번
박민재 (2011학번) 30
채석주 (2013학번) 22
이병학 (2013학번) 20
박지민 (2012학번) 19
박훈민 (2013학번) 15
장기정 (2014학번) 14
허원영 (2014학번) 4
정성진 (2013학번) 3
김태겸 (2013학번) 3
윤준기 (2014학번) 3
GD Star Rating
# Solution: 2014-24 Random points on a sphere
Suppose that $$n$$ points are chosen randomly on a sphere. What is the probability that all points are on some hemisphere?
The best solution was submitted by 채석주 (수리과학과 2013학번). Congratulations!
Here is his solution of 2014-24.
An alternative solution was submitted by 이병학 (수리과학과 2013학번, +3).
GD Star Rating
Let $$f:[0,1]\to \mathbb R$$ be a differentiable function with $$f(0)=0$$, $$f(1)=1$$. Prove that for every positive integer $$n$$, there exist $$n$$ distinct numbers $$x_1,x_2,\ldots,x_n\in(0,1)$$ such that $\frac{1}{n}\sum_{i=1}^n \frac{1}{f'(x_i)}=1.$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7830483317375183, "perplexity": 29245.628185951075}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703521987.71/warc/CC-MAIN-20210120182259-20210120212259-00442.warc.gz"} |
https://www.experts-exchange.com/questions/27382274/vbs-script-to-copy-file-to-another-computer-and-test-speed-time.html | Solved
# vbs script to copy file to another computer and test speed/time
Posted on 2011-10-05
363 Views
Hi,
Does anyone know of a vb or similar script that i can use to copy a file from one computer to another and then report how long it took and the speed it took?
It would be great if the script would ask me the location of the computer that I want to copy the file to (example \\computer\shared_folder)
it would also be great if it could output the time it took and speed it took to a log file like C:\folder\speed_test.log
0
Question by:GTechForce
LVL 51
Expert Comment
Why not just use ROBOCOPY for this test, it gives you those type of stats.
For example, doing this:
robocopy . g:\ large.txt
I got this:
-------------------------------------------------------------------------------
ROBOCOPY :: Robust File Copy for Windows
-------------------------------------------------------------------------------
Started : Wed Oct 05 17:02:33 2011
Source : c:\ee\
Dest : g:\
Files : large.txt
Options : /COPY:DAT /R:1000000 /W:30
------------------------------------------------------------------------------
1 c:\ee\
100% New File 9.5 m LARGE.TXT
------------------------------------------------------------------------------
Total Copied Skipped Mismatch FAILED Extras
Dirs : 1 0 1 0 0 0
Files : 1 1 0 0 0 0
Bytes : 9.53 m 9.53 m 0 0 0 0
Times : 0:00:01 0:00:01 0:00:00 0:00:00
Would be easy to put that in a BAT file and use PROMPT to ask for the computer name to copy to, let me know if you need help with that.
~bp
0
Author Comment
if you wouldnt mind doing that, i would greatly appreciate it. I dont know much about coding.
0
Author Comment
actually after looking into robocopy, that won't work for windows Server 2003 since its not part of the standard features.
is there another way of doing it?
0
LVL 51
Expert Comment
Can you download it from the resource kit and place it on the server?
~bp
0
Author Comment
Ya i can do that. I bet i could setup the script so if robocopy is not installed i could download it,and then have it run the command?
what do i need to do to use the prompt feature to ask for the computer name and location?
0
LVL 51
Accepted Solution
Hope this makes sense, it will prompt for the destination computer and folder path and then do the copy. It will display the results to the screen, and also save it to a logfile. Update the SETs at the top of the script as needed. Save as a BAT file.
@echo off
REM Define folders and files to be used for copy and logging
set BaseDir=c:\basefolder
set TestFile=testfile.txt
set LogFile=logfile.txt
REM Prompt for computer name
set Computer=
set /P Computer=Enter computer name:
REM If a computer name was entered, do the timing test
if defined Computer (
robocopy "%BaseDir%" "%Computer%" "%TestFile%" /TEE /LOG:"%LogFile%"
)
~bp
0
Author Closing Comment
this worked perfectly!
0
LVL 51
Expert Comment
Great, glad that helped, thanks for the feedback.
~bp
0
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how to add IIS SMTP to handle application/Scanner relays into office 365. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7273304462432861, "perplexity": 4241.6311870585405}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988718840.18/warc/CC-MAIN-20161020183838-00205-ip-10-171-6-4.ec2.internal.warc.gz"} |
https://gianlubaio.blogspot.com/2016/08/national-lottery.html | ## Wednesday, 17 August 2016
### National lottery
Yesterday, many British newspapers have covered the news of the new Dementia Atlas, released by the Department of Health.
As far as I can see, the atlas uses data from a variety of sources (including the Quality Outcomes Framework, QOF, scheme, which collects information from general practices around the country, providing incentives to the doctors to record data on key indicators).
So far so good $-$ nothing wrong with that. In fact, cool representation with maps highlighting geographical variation across England and providing rates for several summary statistics, eg prevalence of dementia, level of diagnosis, etc. As usual, though, the media couldn't resist jumping on the news and making a meal of it, mostly by presenting it with grand headlines, which in many cases missed the point, or bluntly mis-represented reality, I think.
For example, beloved Daily Mail and The Telegraph yell about "Post-code lottery in care". Now, it may well be that the data reveal massive inequality in the access to care and diagnosis across the country, which is a very good thing to expose in order to tackle it and then remove it or at least limit it $-$ that's in the spirit of the NHS. But, although I think the website should have made a much better job at explaining the numbers reported, it appears that the information presented in the maps is about the raw rates! It's not quite clear then whether the background characteristics of each area (defined in terms of Clinical Commissioning Group, CCG) do play a role in explaining away some of the differences in the actual rates for each of the measures reported in the table.
So may well be that we're playing Peter Griffin's lottery with people's health. Or there may be much more than that. But some media just don't care about which is which...
#### 1 comment:
1. This comment has been removed by the author. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.23766577243804932, "perplexity": 1188.0367408910429}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-47/segments/1542039744803.68/warc/CC-MAIN-20181119002432-20181119024432-00473.warc.gz"} |
https://www.physicsforums.com/threads/frequency-of-light-question.35619/ | # Frequency Of Light Question
1. Jul 18, 2004
### zoobyshoe
I am starting to slowly read QED, by Richard Feynman.
He is quite adamant that light is particles, and not waves, and he cites the evidence of the action of the device called the photomultiplier to explain his stance. I find this argument completely convincing.
However, looking at the photon as a particle causes me some confusion whenever he, or anyone, mentions the frequency of light.
Viewed as a particle, I have no idea whatever what is occuring at a given frequency to say that it even has a frequency.
Sometimes I wonder if this means that so many particles per unit time pass a given point. At other times I wonder if each individual photon possess its own frequency in some regard: is it spinning at a certain number of spins per unit time, or is it, maybe, undulating somehow a certain number of times per unit time?
So, my question is "Does an individual photon have a frequency, and if so, what is it doing at that frequency?"
-Zooby
2. Jul 18, 2004
### jamie
If you believe in string theory then a single photon will have frequency.but if you stick to classical physics you will will encounter the wave/particle duality.
this says that light has both wave and particle properties and many experiments have reinforced this especially youngs double slit.
regards
jamie
3. Jul 18, 2004
### Tyger
The frequency is defined as the change of quantum mechanical phase per unit time. That is to say, the quantum mechanical phase associated with the amplitude for the state, photon, electron, etc.. Analogously the wavenumber is the QM phase change per unit length. The are associated with the classical quantities energy and momentum, which combine to make a fourvector, the fourmomentum or fourwavenumber. The factor of conversion is h, Planck's constant.
It will get a good deal more interesting and complicated before you really begin to understand what it happening. The waves interfere with each other constructively and destructively in space and time, e.g. in the two slit experiment, producing effects which are not describable by classical mechanics.
4. Jul 18, 2004
### speeding electron
In 'traditional' quantum theory, if you like, i.e. before De Broglie, Schroedinger and wavefunctions etc., each photon has a frequency, which manifests itself in the energy of each photon. If the light has a higher frequency, it means that each photon is more energetic, -not- that more photons pass per unit time. This (more photons passing) means that the light has greater intensity.
5. Jul 18, 2004
### rayjohn01
limited wave
In my book on early QM they used the classical description of a wave bunch to get the idea over . If you take several sinewaves and add them together( especially ones which have harmonic frequency reations) the effect is to produce a wave form with a modulated amplitude which looks like bunches of waves ( the bunches are repeated). They then go on to imagine an infinite set of sines with a limited bandwidth , the results are that you end up with one wave bunch of a given length and shape. This bunch has an average frequency related to the group chosen. The maths is based on the fourier transform -- standard maths. This bunch however exhibits properties similar to the quantum mechanical concepts of property pairs momentum versus position etc and in fact can be used to deduce an approximation for h Planks constant. Although limited the model lets you ask questions such as -- how long is a photon-- it lets you picture more energy by showing how higher frequencies results in more waves in a bunch , it allows for self interference over some length range which lets you picture the double slit experiment ( however inaccurately).
I am not sure if this analogy is still used, QM has come a long way, but it does help envisage a particle ( localised) with wave properties and the maths is real.
6. Jul 19, 2004
### zoobyshoe
Thanks everyone. These answers have been pretty helpful. I am clear now about the fact that the frequency of light has nothing to do with number of photons passing a given point per unit time, which is a good notion to be rid of, and that it does have to do with something the photon itself is doing at a certain frequency: changing its Quantum Mechanical Phase.
The rest will take me some time to mull over and sort out.
Thanks,
-Zooby
7. Jul 19, 2004
Staff Emeritus
Not phase but energy and momentum. For a massless particle in relativity they are numberically equal. The frequency is the momentum divided by Planck's constant.
8. Jul 19, 2004
### dlgoff
From your knowledge of bosonic string theory, does the string representing the photon operate in the curled up dimensions? It seems like maybe it only has to be in 4-d spacetime. Does the photon frequency (or momentum) directly relate to any string parameter?
Don
9. Jul 20, 2004
Staff Emeritus
The oscillations of the string are what (are supposed to) generate the particles we experience. The string oscillates in all the transverse dimensions (that is the dimensions not internal to its world-sheet). This includes the compacted ones. There are exceptions where the string has its endpoints on two different branes and the branes are in various configurations.
10. Jul 21, 2004
### stewarta
yes but what if it is all wrong... i know i know... but what if all photons from a standard light source weren't identical... what if they had a range of speeds and the result of viewing tham all was a white light. i think that if we measured light for specific speeds we would find slow light and fast light. i don't have much of a reference for this idea but my own, but it fits, and explains alot. especially when put to the test by the "red shift-blue shift" of a black hole.
11. Jul 21, 2004
### zoobyshoe
I would imagine that someone has done this. Since the invention of the laser it is possible to have light all of one "color" i.e. frequency to test. I haven't heard of it, but I would be surprised if someone hadn't already checked to see if there is a different speed noticable for different specific colors.
It seems, too, pretty obvious from what has been pointed out in this this thread, that all photons are different from each other in many regards. (The single regard in which they aren't suspected of differing is the speed at which they all propagate.)
Last edited: Jul 21, 2004
12. Jul 21, 2004
### ZapperZ
Staff Emeritus
http://www.aip.org/enews/physnews/1999/split/pnu432-2.htm [Broken]
[Exact citation: B. Schaefer, PRL v.82, p.4964 (1999).]
To date, that is the most accurate measurement of light of different freq. This means that we have no experimental evidence using the best technique we have so far of validating your "what if's".
Zz.
Addendum: This just came out. A new expt. measurement of the speed of light at extremely low freq., in the range of 5 to 50 Hz![1] Again, no detectable deviation, and based on the accuracy and limitations of the measurement, this puts the upper limit on any possible photon rest mass at less than 4 x 10^-52 kg (!!). This number keeps getting smaller and smaller with each subsequent refinement and improved measurement.
[1] M. Fullekrug, PRL v.93, p.043901 (2004).
Last edited by a moderator: Apr 21, 2017 at 7:34 AM
13. Aug 16, 2004
### zoobyshoe
How, in practical terms, did Feynman figure out the beginning and ending direction of the stopwatch pointer? The concept is clear to me, but I don't see how anyone could accurately time a photon over such a short distance at such an enormously fast frequency. What is the trick to this?
14. Aug 16, 2004
### zoobyshoe
I am familiar with Fizeau and MM, but it occured to me that some different means of measuring the speed of light must be used for the very faint light from stars and events in far space. How do they gather such light, and measure its speed these days?
15. Aug 16, 2004
### kawikdx225
I also started reading QED a few days ago and I think you misunderstand what he was doing with the arrows. He wasn't measuring the speed of light, he already knew that. And since he also knew the distance, he could calculate the time. That's how he knew how far the clock hand would move.
Please correct me if I'm wrong, I'm just learning this stuff too.
16. Aug 16, 2004
### kawikdx225
OOPS, I meant to quote post#13.
I dont think the starting position of the clock is important as long as it's used for all arrows, it's the difference between arrows that gives the result.
17. Aug 16, 2004
### zoobyshoe
Please. I KNOW he's not measuring the speed of light.
This is what I'm asking: how could he know the distance when a photon might take any possible path? Any photon that refelected and picked up by the photomultiplier may have reflected off the front or the rear surface. He implies that he is able to time the photons and derive the length of the path from the time.
18. Aug 16, 2004
### kawikdx225
Oh sorry, we must be reading different books.
19. Aug 16, 2004
### NEOclassic
All photons of length <15 nm to >9000 nm are particles
The range noted in the title dwarfs the visible range of ~ 400 nm to 900 nm. It should be remembered that, for hundreds of years and long before the velocity of light was measured, spectral emissions were known only by
their lengths; only after "c" was known, was it possible to compute a pseudo-frequency: f = c/photon length. On the contrary, Faraday/Maxwell AC radio transmissions rightly have a reciprocal relation because they are truely electromagnetic waves.
Incidentally, although RPF's "QED" includes a 40-page Chap 2 (Photons: Particles of Light); the second chapter of Vol I of his lectures, page 2-5, shows that light is listed with the acknowleged wave phenomena of Radio Radar etc - of course it should have been listed with his particles group that included UV-, x- and gamma- particles (i.e., not rays). Cheers, Jim
20. Aug 17, 2004
### zoobyshoe
What do you mean by the term "spectral emission"?
What do you mean by "pseudo-frequency"? Are you saying the frequencies we ascribe to light are guesses or estimates, or are you saying the whole concept of light having a frequency is "pseudo"?
What do you mean by "Faraday/Maxwell AC radio transmissions"? (It's the "radio" part I'm wondering about. Obviously those two didn't work with radio.) And a reciprocal relation to what?
Yes the whole issue of EM waves vs photons(light) is one I was going to ask about specifically at some point. Maxwell, still aether-bound, asserted they were two related disturbances in the same medium, but not that they were exactly the same thing. Einstein, if I recall correctly, believed there was a kind of threshhold beyond which EM became photons, but I don't know the details. They both arise in the electric field, but I'm wondering how clear anyone is about the cut off, or threshold, between the two. I have been under the impression that as low as infra-red we already have photons.
Similar Discussions: Frequency Of Light Question | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8400064706802368, "perplexity": 877.8870791853542}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917118743.41/warc/CC-MAIN-20170423031158-00429-ip-10-145-167-34.ec2.internal.warc.gz"} |
https://onionesquereality.wordpress.com/tag/manifold-learning/ | Feeds:
Posts
## The Jacobian Inner Product
This post may be considered an extension of the previous post.
The setup and notation is the same as in the previous post (linked above). But to summarize: Earlier we had an unknown smooth regression function $f: \mathbb{R}^d \to \mathbb{R}$. The idea was to estimate at each training point, the gradient of this unknown function $f$, and then taking the sample expectation of the outerproduct of the gradient. This quantity has some interesting properties and applications.
However it has its limitations, for one, the mapping $f: \mathbb{R}^d \to \mathbb{R}$ restricts the Gradient Outer Product being helpful for only regression and binary classification (since for binary classification the problem can be thought of as regression). It is not clear if a similar operator can be constructed when one is dealing with classification, that is the unknown smooth function is a vector valued function $f: \mathbb{R}^d \to \mathbb{R}^c$ where $c$ is the number of classes (let us say for the purpose of this discussion, that for each data point we have a probability distribution over the classes, a $c$ dimensional vector).
In the case of the gradient outer product since we were working with a real valued function, it was possible to define the gradient at each point, which is simply:
$\displaystyle \Bigg[ \frac{\partial f}{\partial x_1}, \frac{\partial f}{\partial x_2}, \dots, \frac{\partial f}{\partial x_d} \Bigg]$
For a vector valued function $f: \mathbb{R}^d \to \mathbb{R}^c$, we can’t have the gradient, but instead can define the Jacobian at each point:
$\displaystyle \mathbf{J} = \begin{bmatrix} \frac{\partial f_1}{\partial x_1} & \frac{\partial f_1}{\partial x_2} & \dots & \frac{\partial f_1}{\partial x_d} \\ \vdots & \vdots & \ddots & \vdots \\ \frac{\partial f_c}{\partial x_1} & \frac{\partial f_c}{\partial x_2} & \dots & \frac{\partial f_c}{\partial x_d}\end{bmatrix}$
Note that $\mathbf{J}$ may be estimated in a similar manner as estimating gradients as in the previous posts. Which leads us to define the quantity $\mathbb{E}_X G(X) = \mathbb{E}_X ( \mathbf{J}^T \mathbf{J})$.
The first thing to note is that $\mathbb{E}_X G(X) = \mathbb{E}_X ( \nabla f(X)\nabla f(X)^T)$ defined in the previous post is simply the quantity for the special case when $f: \mathbb{R}^d \to \mathbb{R}$. Another note is also in order: The reason why we suffixed that quantity with “outer product” (as opposed to “inner product” here) is simply because we considered the gradient to be a column vector, otherwise they are similar in spirit.
Another thing to note is that it is easy to see that the quantity $\mathbb{E}_X G(X) = \mathbb{E}_X ( \mathbf{J}^T \mathbf{J})$ is a positive semi-definite matrix and hence is a Reimannian Metric, which is defined below:
Definition: A Reimannian Metric $G$ on a manifold $\mathcal{M}$ is a symmetric and positive semi-definite matrix, which defines a smoothly varying inner product in the tangent space $\mathbf{T}_x \mathcal{M}$, for each point $x \in \mathcal{M}$ and $a, b \in \mathbf{T}_x \mathcal{M}$. This associated p.s.d matrix is called the metric tensor. In the above case, since $\mathbb{E}_X G(X) = \mathbb{E}_X ( \mathbf{J}^T \mathbf{J})$ is p.s.d it defines a Reimannian metric:
$\langle a, b \rangle_x = a^T \mathbb{E}_X ( \mathbf{J}^T \mathbf{J}) b$
Thus, $\mathbb{E}_X ( \mathbf{J}^T \mathbf{J})$ is a specific metric (more general metrics are dealt with in areas such as metric learning).
Properties: We saw some properties of $\mathbb{E}_X G(X) = \mathbb{E}_X ( \nabla f(X)\nabla f(X)^T)$ in the previous post. In the same vein, does $\mathbb{E}_X G(X) = \mathbb{E}_X ( \mathbf{J}^T \mathbf{J})$ have similar properties? i.e. does the first eigenvector also correspond to the direction of highest average variation? What about the $k$-dimensional subspace? What difference does it make that we are looking at a vector valued function? Also what about the cases when $d > c$ and otherwise?
These are questions that I need to think about and should be the topic for a future post to be made soon, hopefully.
Recently, in course of a project that I had some involvement in, I came across an interesting quadratic form. It is called in the literature as the Gradient Outer Product. This operator, which has applications in supervised dimensionality reduction, inverse regression and metric learning can be motivated in two (related) ways, but before doing so, the following is the set up:
Setup: Suppose we have the usual set up as for nonparametric regression and (binary) classification i.e. let $Y \approx f(X)$ for some unknown smooth $f$, the input $X$ is $d$ dimensional $X = (X^i)_{i=1}^d$
1. Supervised Dimensionality Reduction: It is often the case that $f$ varies most along only some relevant coordinates. This is the main motivation behind variable selection.
The idea in variable selection is the following: That $f(X)$ may be written as $f(PX)$ where $P \in \{0,1\}^{k \times d}$. $P$ projects down the data to only $k$ relevant coordinates (i.e. some features are selected by $P$ while others are discarded).
This idea is generalized in Multi-Index Regression, where the goal is to recover a subspace most relevant to prediction. That is, now suppose the data varies significantly along all coordinates but it still depends on some subspace of smaller dimensionality. This might be achieved by letting $P$ from the above to be $P \in \mathbb{R}^{k \times d}$. It is important to note that $P$ is not any subspace, but rather the $k$-dimensional subspace to which if the data is projected, the regression error would be the least. This idea might be further generalized by means of mapping $X$ to some $P$ non-linearly, but for now we only stick to the relevant subspace.
How can we recover such a subspace?
________________
2. Average Variation of $f$: Another way to motivate this quantity is the following: Suppose we want to find the direction in which $f$ varies the most on average, or the direction in which $f$ varies the second fastest on average and so on. Or more generally, given any direction, we want to find the variation of $f$ along it. How can we recover these?
________________
The Expected Gradient Outer Product: The expected gradient outer product of the unknown classification or regression function is the quantity: $\mathbb{E}_X G(X) = \mathbb{E}_X ( \nabla f(X)\nabla f(X)^T)$
The expected gradient outer product recovers the average variation of $f$ in all directions. This can be seen as follows: The directional derivative at $x$ along $v \in \mathbb{R}^d$ is given by $\displaystyle {f'}_v(x) = \nabla f(x)^T v$ or $\mathbb{E}_X |{f'}_v(X)|^2 = \mathbb{E}_X (v^T G(X) v) = v^T (\mathbb{E}_X G(X))v$.
From the above it follows that if $f$ does not vary along $v$ then $v$ must be in the null space of $\mathbb{E}_X (G(X))$.
Infact it is not hard to show that the relevant subspace $P$ as defined earlier can also be recovered from $\mathbb{E}_X (G(X))$. This fact is given in the following lemma.
Lemma: Under the assumed model i.e. $Y \approx f(PX)$, the gradient outer product matrix $\mathbb{E}_X (G(X))$ is of rank at most $k$. Let $\{v_1, v_2, \dots, v_k \}$ be the eigenvectors of $\mathbb{E}_X (G(X))$ corresponding to the top $k$ eigenvalues of $\mathbb{E}_X (G(X))$. Then the following is true:
$span(P) = span(v_1, v_2, \dots, v_k)$
This means that a spectral decomposition of $\mathbb{E}_X (G(X))$ recovers the relevant subspace. Also note that the Gradient Outer Product corresponds to a kind of a supervised version of Principal Component Analysis.
________________
Estimation: Ofcourse in real settings the function is unknown and we are only given points sampled from it. There are various estimators for $\mathbb{E}_X (G(X))$, which usually involve estimation of the derivatives. In one of them the idea is to estimate, at each point $x$ a linear approximation to $f$. The slope of this approximation approximates the gradient at that point. Repeating this at the $n$ sample points, gives a sample gradient outer product. There is some work that shows that some of these estimators are statistically consistent.
________________
Related: Gradient Based Diffusion Maps: The gradient outer product can not isolate local information or geometry and its spectral decomposition, as seen above, gives only a linear embedding. One way to obtain a non-linear dimensionality reduction would be to borrow from and extend the idea of diffusion maps, which are well established tools in semi supervised learning. The central quantity of interest for diffusion maps is the graph laplacian $L = I - D^{-\frac{1}{2}} W D^{-\frac{1}{2}}$, where $D$ is the degree matrix and $W$ the adjacency matrix of the nearest neighbor graph constructed on the data points. The non linear embedding is obtained by a spectral decomposition of the operator $L$ or its powers $L^t$.
As above, a similar diffusion operator may be constructed by using local gradient information. One such possible operator could be:
$\displaystyle W_{ij} = W_{f}(x_i, x_j) = exp \Big( - \frac{ \| x_i - x_j \| ^2}{\sigma_1} - \frac{ | \frac{1}{2} (\nabla f(x_i) + \nabla f(x_j)) (x_i - x_j) |^2 }{\sigma_2}\Big)$
Note that the first term is the same that is used in unsupervised dimension reduction techniques such as laplacian eigenmaps and diffusion maps. The second term can be interpreted as a diffusion on function values. This operator gives a way for non linear supervised dimension reduction using gradient information.
The above operator was defined here, however no consistency results for the same are provided.
Also see: The Jacobian Inner Product.
________________ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 79, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9721553325653076, "perplexity": 181.50280147839638}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030335276.85/warc/CC-MAIN-20220928180732-20220928210732-00164.warc.gz"} |
https://tex.stackexchange.com/questions/287387/siunitx-the-detect-all-option-puts-celsius-in-math-mode | # siunitx: the detect-all option puts \celsius in math mode? [closed]
Something is wrong with the Celsius unit and the detect-all option (see below).
I finally removed the detect-all option to fix the problem, but still, there may be some bug here.
MWE:
\documentclass[11pt,a4paper,openright,twoside]{book}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{siunitx}
\begin{document}
\chapter{What is happening here?}
Good: \SI{50}{\celsius}, \SI{30}{\watt\per\meter}.\\
\sisetup{detect-all}
But after \verb=\sisetup{detect-all}=, the celsius unit (and only this one) is in math mode: \SI{50}{\celsius}, \SI{30}{\watt\per\meter}.
\end{document}
## closed as off-topic by LaRiFaRi, Zarko, moewe, Svend Tveskæg, MenschMar 15 '16 at 14:53
• This question does not fall within the scope of TeX, LaTeX or related typesetting systems as defined in the help center.
If this question can be reworded to fit the rules in the help center, please edit the question.
• @LaRiFaRi I think I know what's going on here: trying to satisfy all requirements is hard! – Joseph Wright Jan 13 '16 at 9:06
• Bibi, no worries, Joseph did not say that you are asking for something special. I guess he was just a bit resigned as he was introducing some fix for some other issue just two weeks ago. As you are having the most recent TL-version, it seems as if you have found some more work for him... We'll see. – LaRiFaRi Jan 13 '16 at 9:17
• I'll need to think a bit to find a solution that works for all of the issues: may take a day or so. – Joseph Wright Jan 13 '16 at 9:30
• @JosephWright: I just noticed the problem is gone! Thanks! – Bibi Feb 2 '16 at 17:32
• I'm voting to close this question as off-topic because it is about a problem with has been fixed in the meantime. – LaRiFaRi Mar 15 '16 at 14:14 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8313774466514587, "perplexity": 1521.7720590234608}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570987836368.96/warc/CC-MAIN-20191023225038-20191024012538-00039.warc.gz"} |
https://meridian.allenpress.com/radiation-research/article-abstract/124/3/326/39009/Physical-Basis-for-Detection-of-DNA-Double-Strand?redirectedFrom=fulltext | Results using neutral filter elution are difficult to explain if this method detects only DNA double-strand breaks (DSBs). In an attempt to understand neutral filter elution, the size of DNA pieces eluted from filters was measured using pulsed-field gel electrophoresis. Contrary to expectation, the size of the pieces was independent of radiation dose and time of elution, and much smaller (∼460 kb) than anticipated based on the expected number of DSBs induced. Shearing of the DNA molecule, the presence of nonspecific nucleases, and the influence of DNA-associated proteins were examined but could not explain our results. Consequently, we propose that cell lysis causes swelling of the DNA gel, and the exposed fraction of DNA on the surface of the gel is then sheared as the elution solution flows through the filter. We suggest that the rate of DNA elution measured using neutral filter elution is dependent upon the number of DSBs present, the composition of the eluting solution, especially with regard to the presence of molecules which can influence chromatin swelling on the filter, and the conformation or "packaging" of DNA before lysis.
This content is only available as a PDF. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9062755107879639, "perplexity": 2691.6009015077625}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178351374.10/warc/CC-MAIN-20210225153633-20210225183633-00540.warc.gz"} |
https://www.physicsforums.com/threads/mesons-baryons-and-leptons.43665/ | # Mesons, Baryons, and Leptons
1. Sep 19, 2004
### KaneOris
Does anyone know how many there are, also how many are just thoeretical. We know of the proton, neutron, and election, but do we know that Tau and Muons exist? Also does anyone think we'll keep finding more
2. Sep 19, 2004
### misogynisticfeminist
all particles in the standard model have been confirmed experimentally. Muons, taus etc. The only thing is the higgs and sparticles which are entirely theoretical.
3. Sep 19, 2004
### marlon
4. Sep 19, 2004
### mathman
Most of these elementary particles were discovered before the quark model was created. I remember seeing a discusssion on PBS with Oppenheimer about all the various mesons and speculating about the existence of some underlying theory to explain what was then considered a mess.
5. Sep 30, 2004
### Mk
Yes, the muon and tau were both discovered before any quark theories | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9709926247596741, "perplexity": 2030.1118545681695}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-50/segments/1480698541696.67/warc/CC-MAIN-20161202170901-00073-ip-10-31-129-80.ec2.internal.warc.gz"} |
https://groupprops.subwiki.org/wiki/Sylow_not_implies_CDIN | # Sylow not implies CDIN
This article gives the statement and possibly, proof, of a non-implication relation between two subgroup properties. That is, it states that every subgroup satisfying the first subgroup property (i.e., Sylow subgroup) need not satisfy the second subgroup property (i.e., CDIN-subgroup)
View a complete list of subgroup property non-implications | View a complete list of subgroup property implications
EXPLORE EXAMPLES YOURSELF: View examples of subgroups satisfying property Sylow subgroup but not CDIN-subgroup|View examples of subgroups satisfying property Sylow subgroup and CDIN-subgroup
## Statement
We can have a group $G$ with a Sylow subgroup $P$ and elements $x,y \in P$ such that $x$ and $y$ are conjugate in $G$ but not in $N_G(P)$. In other words, $P$ is not a CDIN-subgroup.
## Related facts
• Sylow and TI implies CDIN: If we assume the additional condition that the Sylow subgroup intersects all its distinct conjugates trivially, then any two elements of it that are conjugate in the whole group are, in fact, conjugate in its normalizer.
## Proof
### Example of the symmetric group of degree four
Further information: symmetric group:S4, dihedral group:D8
Let $G$ be the symmetric group of degree four, say, on the set $\{ 1,2,3,4 \}$. Let $P$ be a $2$-Sylow subgroup of $G$, say:
$P = \{ (), (1,2,3,4), (1,3)(2,4), (1,4,3,2), (1,3), (2,4), (1,2)(3,4), (1,3)(2,4) \}$.
Note that $P$ is a $2$-Sylow subgroup of $G$, and is a dihedral group of order eight. Consider the elements of $P$ given by:
$x = (1,3)(2,4), \qquad y = (1,2)(3,4)$.
• $x$ and $y$ are conjugate in $G$: The element $(2,3)$, for instance, conjugates $x$ to $y$.
• $P = N_G(P)$: Since $P$ has index three in $G$, either $N_G(P) = P$ or $N_G(P) = G$. But the element $(1,2)$, for instance, does not normalize $P$. This forces $N_G(P) = P$.
• $x$ and $y$ are not conjugate in $P = N_G(P)$: In fact, $x$ is in the center of $P$, and $y$ is not in the center of $P$. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 40, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.963106632232666, "perplexity": 294.2140143327337}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370503664.38/warc/CC-MAIN-20200331181930-20200331211930-00356.warc.gz"} |
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Will internal links work in php? like for an include? EG:
PHP Code:
``` include("http://192.168.1.200/something.txt"); ```
I have like 4 servers on my network and they are all paths after a domain but they have names(server1, serv...) and it would be alot easier to type include("http://server3/file.daf"); then some long path.
Also while writing this I came up with another question.
Say I have 2 servers(server1, and server2) Server 1 is on my network but server 2 is remotly hosted. I have an include on server2 that points to a file on server 1. That file is include.php In that file are includes to a dir on server 1.
My question is What is processed first? Will the dir be assumed to be on server1 or server2?
Sorry if I lost ya in that last one, and its not that important anyway, i was just wondering...
Thanks,
ILLINI
• include("http://192.168.1.200/something.txt");
would work assuming the computer @ .200 has a webserver running, note that you cant get the file source (of say php/perl etc) this way since the webserver will already have parsed them, to include php files for later processing you would want to access the network path \\network-server1\\files\\include.php
includes will be relative to the calling script , so if blah.php is on server4 then the script will look for relative paths on server4 , not 2 or 1 or 3 etc.
• ok thank you. I was just wondering, because I did it but have no way of testing it because the addresses would work for me anyway because they are on my network.
•
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https://www.mathscinotes.com/2012/01/worked-pagerank-example/ | # Worked PageRank Example
## Introduction
One of my sons asked me if I could work through a PageRank calculation example a couple of different ways (algebraic and iterative). It was an interesting exercise and I thought it would be worth documenting here. I used Mathcad for both my algebraic and iterative solutions.
Wikipedia has an excellent definition of the PageRank algorithm, which I will quote here.
PageRank is a link analysis algorithm, named after Larry Page[1] and used by the Google Internet search engine, that assigns a numerical weighting to each element of a hyperlinked set of documents, such as the World Wide Web, with the purpose of “measuring” its relative importance within the set.
Businesses and individuals who want their site to rank more highly in Google’s search results could look at the services of a Digital Marketing Company to help boost their position.
PageRank is computed using a relatively simple function (see Equation 1), but a number of web-based examples treat the weighting of inbound links from sites external to a particular group of pages as a special case. I did not see any explicit calculation examples, so I thought I would include this calculation here. You’ll more than definitely want to take this calculation into consideration if you’re wanting to learn to how to build a website as well as wishing to attract traffic to your new site. Speaking of which, are you in the process of designing a new website? Whether you are a business or a blogger, running a website ensures that people that are interested in your products or services can learn about them with ease. So, have a web designing agency like The Web Designer Cardiff (click here) to have one made for you professionally. Furthermore, thanks to the advent of website building tools, creating a website has never been more accessible. For a summary of some of the most widely used website builders, head to this makeawebsitehub guide.
## Background
PageRank views the web as graph, with inbound links being viewed as measure of the significance of a web page. Equation 1 shows the PageRank equation. Note that this equation can be solved several different ways. One approach involves eigenvalues, which my son does not know about yet. The equation can be solved algebraically or iteratively. I will use both approaches for this example.
Eq. 1 $PR\left( {{p}_{i}} \right)=\frac{1-d}{N}+d\cdot \sum\limits_{p\in M\left( {{p}_{i}} \right)}{\frac{PR\left( {{p}_{j}} \right)}{L\left( {{p}_{j}} \right)}}$
where
• N is the number of pages.
• d is called the damping factor and it is an arbitary weighting factor.
• PR(pi is the PageRank of page pi.
• L(pi) is the number of outbound links from page pi.
• M(pi) is the set of links to page pi.
Equation 2 shows a matrix form of Equation 1. The matrix form is most likely the form used “out in the wild.”
Eq. 2 $\mathbf{R}(t+1)=d\cdot \mathcal{M}\cdot \mathbf{R}(t)+\frac{1-d}{N}\cdot \mathbf{1}\text{ }~$
where
• R is the PageRank vector.
• 1 is a column vector with all elements equal to 1.
• t is a discrete time variable (really a sequence number).
Note that many examples of PageRank are computed using a variant of Equations 1 and 2 that multiplies the PageRank value by the number of pages (N ·PageRank). Equation 3 illustrates Equation 2 modified with the substitution $\mathbf{{R}'}=N\cdot \mathbf{R}$. Equation 1 can be modified similarly. This is the equation that Ian used for his examples. Since I am going to duplicate his results, I will multiply my results by N.
Eq. 3 $N\cdot \mathbf{R}(t+1)=N\cdot d\cdot \mathcal{M}\cdot \mathbf{R}(t)+N\cdot \frac{1-d}{N}\cdot \mathbf{1}$ $\left( N\cdot \mathbf{R}(t+1) \right)=d\cdot \mathcal{M}\cdot \left( N\cdot \mathbf{R}(t) \right)+\left( 1-d \right)\cdot \mathbf{1}$ $\therefore \quad \mathbf{{R}'}(t+1)=d\cdot {\mathcal{M}}'\cdot \mathbf{{R}'}(t)+\left( 1-d \right)\cdot \mathbf{1},\text{ where }\mathbf{{R}'}=N\cdot \mathbf{R}$
There has been quite a bit written about the nuances of this equation because of its importance in determining a web page’s position in a list of search results. I am not concerned about those details here. I am focused here on the calculation of the PageRank for a specific set of pages.
## Analysis
### Example
My son was using Ian Roger’s excellent site for learning about the details of PageRank. The question he had is on Example 10, which assigns a PageRank of 1 to an external page. Figure 1 shows the Example 10’s web page configuration. Ian’s PageRank results are shown in the boxes, which represent web pages. I want to show the details on obtaining Ian’s results as an illustration of how to handle an external link from a page with a defined PageRank.
Figure 1: PageRank Example from Ian Roger's Website.
I have added the letters A-F to Figure 1, which constitute the variable names I will use in my solutions.
### Algebraic Solution
When Ian uses a link from an external site, he sets the PageRank value to 1. Here is his rationale.
We’ll assume there’s an external site that has lots of pages and links with the result that one of the pages has the average PR of 1.0.
Algebraically, this is easy to handle. Figure 2 shows my solution implemented in Mathcad.
Figure 2: Algebraic Solution for Example 10.
### Iterative Solution
Figure 3 shows how I setup my iterative solution. To force page A to have a PageRank of 1, I needed to remove page A from the R vector and M matrix, but add it back in so that page A’s contribution can be included. Again, it is a slight modification of Equation 3 so that I can force page A to have a PageRank of 1.
Figure 3: Setup for My Iterative Solution of Equation 2.
Figure 4 shows my iteration stage. Note that I was lazy and simply let it iterate a 1001 times. I could have made this much more efficient by simply monitoring the convergence, but that would have taken a bit more time.
Figure 4: Iterative Solution of Equation 2.
## Conclusion
I obtained the same results as Ian using two different approaches — algebraic and iterative. This example was different than most in that a particular web page was forced to a particular PageRank. I hope that I answered my son’s question.
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https://worldwidescience.org/topicpages/z/zcosmos+galaxies+hosting.html | #### Sample records for zcosmos galaxies hosting
1. Ongoing and co-evolving star formation in zCOSMOS galaxies hosting Active Galactic Nuclei
Silverman, J D; Maier, C; Lilly, S; Mainieri, V; Brusa, M; Cappelluti, N; Hasinger, G; Zamorani, G; Scodeggio, M; Bolzonella, M; Contini, T; Carollo, C M; Jahnke, K; Kneib, J -P; Le Fèvre, O; Merloni, A; Bardelli, S; Bongiorno, A; Brunner, H; Caputi, K; Civano, F; Comastri, A; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Elvis, M; Finoguenov, A; Fiore, F; Franzetti, P; Garilli, B; Gilli, R; Iovino, A; Kampczyk, P; Knobel, C; Kovac, K; Le Borgne, J F; Le Brun, V; Mignoli, M; Pellò, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Vignali, C; Zucca, E; Bottini, D; Cappi, A; Cassata, P; Fumana, M; Griffiths, R; Kartaltepe, J; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Salvato, M
2008-01-01
We present a study of the host galaxies of AGN selected from the zCOSMOS survey to establish if accretion onto supermassive black holes and star formation are explicitly linked up to z~1. We identify 152 galaxies that harbor AGN, based on XMM observations of 7543 galaxies (i<22.5). Star formation rates (SFRs), including those weighted by stellar mass, are determined using the [OII]3727 emission-line, corrected for an AGN contribution. We find that the majority of AGN hosts have significant levels of star formation with a distribution spanning ~1-100 Msun yr^-1. The close association between AGN activity and star formation is further substantiated by an increase in the AGN fraction with the youthfulness of their stars as indicated by the rest-frame color (U-V) and spectral index Dn(4000); we demonstrate that mass-selection alleviates an artifical peak falling in the transition region when using luminosity-limited samples. We also find that the SFRs of AGN hosts evolve with cosmic time in a manner that close...
2. On the cosmic evolution of the scaling relations between black holes and their host galaxies: Broad Line AGN in the zCOSMOS survey
Merloni, A; Bolzonella, M; Brusa, M; Civano, F; Comastri, A; Elvis, M; Fiore, F; Gilli, R; Hao, H; Jahnke, K; Koekemoer, A M; Lusso, E; Mainieri, V; Mignoli, M; Miyaji, T; Renzini, A; Salvato, M; Silverman, Joseph; Trump, J; Vignali, C; Zamorani, G; Capak, P; Lilly, S J; Sanders, D; Taniguchi, Y; Bardelli, S; Carollo, C M; Caputi, K; Contini, T; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Hasinger, G; Impey, C; Iovino, A; Iwasawa, K; Kampczyk, P; Kneib, J -P; Knobel, C; Kovac, K; Lamareille, F; Le Borgne, J F; Le Brun, V; Le Fèvre, O; Maier, C; Pellò, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Scodeggio, M; Tanaka, M; Tasca, L A M; Tresse, L; Vergani, D; Zucca, E
2009-01-01
(Abriged) We report on the measurement of the rest frame K-band luminosity and total stellar mass of the hosts of 89 broad line Active Galactic Nuclei detected in the zCOSMOS survey in the redshift range 1host galaxy from that of the nuclear black hole in their Spectral Energy Distributions. We derive an estimate of black hole masses through the analysis of the broad Mg II emission lines observed in the medium-resolution spectra taken with VIMOS/VLT as part of the zCOSMOS project. We found that, as compared to the local value, the average black hole to host galaxy mass ratio appears to evolve positively with redshift, with a best fit evolution of the form (1+z)^{0.68 \\pm0.12 +0.6 -0.3}, where the large asymmetric systematic errors stem from the uncertainties in the choice of IMF, in the calibration of the virial relation used to estimate BH masses and in the mean QSO SED adopted. A thoroug...
3. ON THE COSMIC EVOLUTION OF THE SCALING RELATIONS BETWEEN BLACK HOLES AND THEIR HOST GALAXIES : BROAD-LINE ACTIVE GALACTIC NUCLEI IN THE ZCOSMOS SURVEY
Merloni, A.; Bongiorno, A.; Bolzonella, M.; Brusa, M.; Civano, F.; Comastri, A.; Elvis, M.; Fiore, F.; Gilli, R.; Hao, H.; Jahnke, K.; Koekemoer, A. M.; Lusso, E.; Mainieri, V.; Mignoli, M.; Miyaji, T.; Renzini, A.; Salvato, M.; Silverman, J.; Trump, J.; Vignali, C.; Zamorani, G.; Capak, P.; Lilly, S. J.; Sanders, D.; Taniguchi, Y.; Bardelli, S.; Carollo, C. M.; Caputi, K.; Contini, T.; Coppa, G.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Hasinger, G.; Impey, C.; Iovino, A.; Iwasawa, K.; Kampczyk, P.; Kneib, J. -P.; Knobel, C.; Kovac, K.; Lamareille, F.; Le Borgne, J. -F.; Le Brun, V.; Le Fevre, O.; Maier, C.; Pello, R.; Peng, Y.; Perez Montero, E.; Ricciardelli, E.; Scodeggio, M.; Tanaka, M.; Tasca, L. A. M.; Tresse, L.; Vergani, D.; Zucca, E.
2010-01-01
We report on the measurement of the physical properties (rest-frame K-band luminosity and total stellar mass) of the hosts of 89 broad-line (type-1) active galactic nuclei (AGNs) detected in the ZCOSMOS survey in the redshift range 1
4. The mass-metallicity relation of zCOSMOS galaxies at z ~ 0.7, its dependence on SFR, and the existence of massive low-metallicity galaxies
Maier, C; Lilly, S J; Contini, T; Montero, E Perez; Lamareille, F; Bolzonella, M; Floc'h, E Le
2014-01-01
(Abridged) The knowledge of the number and of the physical nature of low-metallicity massive galaxies is crucial for the determination and interpretation of the mass-metallicity relation (MZR). Using VLT-ISAAC near-infrared (NIR) spectroscopy of 39 zCOSMOS z~0.7 galaxies, we have measured Halpha and [NII] emission line fluxes for galaxies with [OII], Hbeta and [OIII] available from VIMOS optical spectroscopy. The NIR spectroscopy enables us to break the degeneracy of the R23 method to derive unambiguously O/H gas metallicities, and also SFRs from extinction corrected Halpha. Using, as a benchmark, the position in the D4000 vs. [OIII]/Hbeta diagram of galaxies with reliable O/Hs from NIR spectroscopy, we were able to break the lower/upper branch R23 degeneracy of additional 900 zCOSMOS z~0.7 galaxies. Additionally, the Halpha-based SFR measurements were used to find the best SFR calibration based on [OII] for the zCOSMOS z~0.7 galaxies without Halpha measurements. We find a fraction of 19% of lower mass 9.5<...
5. The zCOSMOS 10k-sample: the role of galaxy stellar mass in the colour-density relation up to z ~ 1
Cucciati, O.; Iovino, A.; Kovač, K.; Scodeggio, M.; Lilly, S. J.; Bolzonella, M.; Bardelli, S.; Vergani, D.; Tasca, L. A. M.; Zucca, E.; Zamorani, G.; Pozzetti, L.; Knobel, C.; Oesch, P.; Lamareille, F.; Caputi, K.; Kampczyk, P.; Tresse, L.; Maier, C.; Carollo, C. M.; Contini, T.; Kneib, J.-P.; Le Fèvre, O.; Mainieri, V.; Renzini, A.; Bongiorno, A.; Coppa, G.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Le Borgne, J.-F.; Le Brun, V.; Mignoli, M.; Pellò, R.; Peng, Y.; Perez-Montero, E.; Ricciardelli, E.; Silverman, J. D.; Tanaka, M.; Koekemoer, A. M.; Scoville, N.; Abbas, U.; Bottini, D.; Cappi, A.; Cassata, P.; Cimatti, A.; Guzzo, L.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Meneux, B.; Porciani, C.; Scaramella, R.
2010-01-01
Aims: With the first ˜10 000 spectra of the flux limited zCOSMOS sample (IAB ≤ 22.5) we want to study the evolution of environmental effects on galaxy properties since z ~ 1.0, and to disentangle the dependence among galaxy colour, stellar mass and local density. Methods: We use our previously deriv
6. MASS AND ENVIRONMENT AS DRIVERS OF GALAXY EVOLUTION IN SDSS AND zCOSMOS AND THE ORIGIN OF THE SCHECHTER FUNCTION
Peng, Ying-Jie; Lilly, Simon J.; Kovac, Katarina; Bolzonella, Micol; Pozzetti, Lucia; Renzini, Alvio; Zamorani, Gianni; Ilbert, Olivier; Knobel, Christian; Iovino, Angela; Maier, Christian; Cucciati, Olga; Tasca, Lidia; Carollo, C. Marcella; Silverman, John; Kampczyk, Pawel; De Ravel, Loic; Sanders, David; Scoville, Nicholas; Contini, Thierry; Mainieri, Vincenzo; Scodeggio, Marco; Kneib, Jean-Paul; Le Fevre, Olivier; Bardelli, Sandro; Bongiorno, Angela; Caputi, Karina; Coppa, Graziano; de la Torre, Sylvain; Franzetti, Paolo; Garilli, Bianca; Lamareille, Fabrice; Le Borgne, Jean-Francois; Le Brun, Vincent; Mignoli, Marco; Montero, Enrique Perez; Pello, Roser; Ricciardelli, Elena; Tanaka, Masayuki; Tresse, Laurence; Vergani, Daniela; Welikala, Niraj; Zucca, Elena; Oesch, Pascal; Abbas, Ummi; Barnes, Luke; Bordoloi, Rongmon; Bottini, Dario; Cappi, Alberto; Cassata, Paolo; Cimatti, Andrea; Fumana, Marco; Hasinger, Gunther; Koekemoer, Anton; Leauthaud, Alexei; Maccagni, Dario; Marinoni, Christian; McCracken, Henry; Memeo, Pierdomenico; Meneux, Baptiste; Nair, Preethi; Porciani, Cristiano; Presotto, Valentina; Scaramella, Roberto
2010-01-01
We explore the simple inter-relationships between mass, star formation rate, and environment in the SDSS, zCOSMOS, and other deep surveys. We take a purely empirical approach in identifying those features of galaxy evolution that are demanded by the data and then explore the analytic consequences of
7. The zCOSMOS 10k-sample : the role of galaxy stellar mass in the colour-density relation up to z similar to 1
Cucciati, O.; Iovino, A.; Kovac, K.; Scodeggio, M.; Lilly, S. J.; Bolzonella, M.; Bardelli, S.; Vergani, D.; Tasca, L. A. M.; Zucca, E.; Zamorani, G.; Pozzetti, L.; Knobel, C.; Oesch, P.; Lamareille, F.; Caputi, K.; Kampczyk, P.; Tresse, L.; Maier, C.; Carollo, C. M.; Contini, T.; Kneib, J. -P.; Le Fevre, O.; Mainieri, V.; Renzini, A.; Bongiorno, A.; Coppa, G.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Le Borgne, J. -F.; Le Brun, V.; Mignoli, M.; Pello, R.; Peng, Y.; Perez-Montero, E.; Ricciardelli, E.; Silverman, J. D.; Tanaka, M.; Koekemoer, A. M.; Scoville, N.; Abbas, U.; Bottini, D.; Cappi, A.; Cassata, P.; Cimatti, A.; Guzzo, L.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Meneux, B.; Porciani, C.; Scaramella, R.
2010-01-01
Aims. With the first similar to 10 000 spectra of the flux limited zCOSMOS sample (I-AB Methods. We use our previously derived 3D local density contrast delta, computed with the 5th nearest neighbour approach, to study the evolution with z of the environmental effects on galaxy U-B colour, D4000 ang
8. MASS AND ENVIRONMENT AS DRIVERS OF GALAXY EVOLUTION IN SDSS AND zCOSMOS AND THE ORIGIN OF THE SCHECHTER FUNCTION
Peng, Ying-Jie; Lilly, Simon J.; Kovac, Katarina; Bolzonella, Micol; Pozzetti, Lucia; Renzini, Alvio; Zamorani, Gianni; Ilbert, Olivier; Knobel, Christian; Iovino, Angela; Maier, Christian; Cucciati, Olga; Tasca, Lidia; Carollo, C. Marcella; Silverman, John; Kampczyk, Pawel; De Ravel, Loic; Sanders, David; Scoville, Nicholas; Contini, Thierry; Mainieri, Vincenzo; Scodeggio, Marco; Kneib, Jean-Paul; Le Fevre, Olivier; Bardelli, Sandro; Bongiorno, Angela; Caputi, Karina; Coppa, Graziano; de la Torre, Sylvain; Franzetti, Paolo; Garilli, Bianca; Lamareille, Fabrice; Le Borgne, Jean-Francois; Le Brun, Vincent; Mignoli, Marco; Montero, Enrique Perez; Pello, Roser; Ricciardelli, Elena; Tanaka, Masayuki; Tresse, Laurence; Vergani, Daniela; Welikala, Niraj; Zucca, Elena; Oesch, Pascal; Abbas, Ummi; Barnes, Luke; Bordoloi, Rongmon; Bottini, Dario; Cappi, Alberto; Cassata, Paolo; Cimatti, Andrea; Fumana, Marco; Hasinger, Gunther; Koekemoer, Anton; Leauthaud, Alexei; Maccagni, Dario; Marinoni, Christian; McCracken, Henry; Memeo, Pierdomenico; Meneux, Baptiste; Nair, Preethi; Porciani, Cristiano; Presotto, Valentina; Scaramella, Roberto
2010-01-01
We explore the simple inter-relationships between mass, star formation rate, and environment in the SDSS, zCOSMOS, and other deep surveys. We take a purely empirical approach in identifying those features of galaxy evolution that are demanded by the data and then explore the analytic consequences of
9. Extreme emission-line galaxies out to z$\\sim$1 in zCOSMOS-20k. I. Sample and characterization of global properties
Amorín, Ricardo; Contini, T; Vílchez, J M; Bolzonella, M; Tasca, L A M; Lamareille, F; Zamorani, G; Maier, C; Carollo, C M; Kneib, J -P; Fèvre, O Le; Lilly, S; Mainieri, V; Renzini, A; Scodeggio, M; Bardelli, S; Bongiorno, A; Caputi, K; Cucciati, O; de la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Knobel, C; Kovač, K; Borgne, J -F Le; Mignoli, V Le Brun M; Pellò, R; Peng, Y; Presotto, V; Ricciardelli, E; Silverman, J D; Tanaka, M; Tresse, L; Vergani, D; Zucca, E
2014-01-01
We present a large sample of 183 extreme emission-line galaxies (EELGs) at redshift 0.11 < z < 0.93 selected from the 20k zCOSMOS Bright Survey by their unusually large [OIII]5007 equivalent widths. Based on emission-line diagnostics, 165 purely star-forming EELGs and 18 narrow-line AGN candidates are identified. Using multiwavelength COSMOS photometry, HST-ACS I-band imaging and optical zCOSMOS spectroscopy we characterize their main physical properties. EELGs are small (R_50 ~ 1.3 kpc), low-mass (M*/Msol~10^7-10^10) galaxies forming stars at unusually high rates (SFR~0.1-35 Msol/yr), being among the highest specific SFRs galaxies in zCOSMOS. Consistently, the EELGs are luminous and extremely compact at rest-frame UV wavelengths and include strong Ly$\\alpha$ emitters, as revealed by GALEX spectroscopy. Using both direct and strong-line methods, we show that zCOSMOS EELGs are low-metallicity systems (12+log(O/H)=8.16 in the median) including several extremely metal-deficient galaxies (<10% solar). Fi...
10. The Colors of Central and Satellite Galaxies in zCOSMOS Out to z ~= 0.8 and Implications for Quenching
Knobel, C.; Lilly, S. J.; Kovac, K.; Peng, Y.; Bschorr, T. J.; Carollo, C. M.; Contini, T.; Kneib, J. -P.; Le Fevre, O.; Mainieri, V.; Renzini, A.; Scodeggio, M.; Zamorani, G.; Bardelli, S.; Bolzonella, M.; Bongiorno, A.; Caputi, K.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Lamareille, F.; Le Borgne, J. -F.; Le Brun, V.; Maier, C.; Mignoli, M.; Pello, R.; Perez Montero, E.; Presotto, V.; Silverman, J.; Tanaka, M.; Tasca, L.; Tresse, L.; Vergani, D.; Zucca, E.; Barnes, L.; Bordoloi, R.; Cappi, A.; Cimatti, A.; Coppa, G.; Koekemoer, A. M.; Lopez-Sanjuan, C.; McCracken, H. J.; Moresco, M.; Nair, P.; Pozzetti, L.; Welikala, N.
2013-01-01
We examine the red fraction of central and satellite galaxies in the large zCOSMOS group catalog out to z similar or equal to 0.8, correcting for both the incompleteness in stellar mass and for the less than perfect purities of the central and satellite samples. We show that at all masses and at all
11. K+a galaxies in the zCOSMOS Survey: Physical properties of systems in their post-starburst phase
Vergani, D; Lilly, S J; Lamareille, F; Halliday, C; Scodeggio, M; Vignali, C; Ciliegi, P; Bolzonella, M; Bondi, M; Kovac, K; Knobel, C; Zucca, E; Caputi, K; Pozzetti, L; Bardelli, S; Mignoli, M; Iovino, A; Carollo, C M; Contini, T; Kneib, J -P; Le Fèvre, O; Mainieri, V; Renzini, A; Bongiorno, A; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Kampczyk, P; Le Borgne, J F; Le Brun, V; Maier, C; Pellò, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Silverman, J D; Tanaka, M; Tasca, L; Tresse, L; Abbas, U; Bottini, D; Cappi, A; Cassata, P; Cimatti, A; Guzzo, L; Koekemoer, A M; Maccagni, A Leauthaud D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Scaramella, R; Capak, P; Sanders, D; Scoville, N; Taniguchi, Y
2009-01-01
The identities of the main processes triggering and quenching star-formation in galaxies remain unclear. A key stage in evolution, however, appears to be represented by post-starburst galaxies. To investigate their impact on galaxy evolution, we initiated a multiwavelength study of galaxies with k+a spectral features in the COSMOS field. We examine a mass-selected sample of k+a galaxies at z=0.48-1.2 using the spectroscopic zCOSMOS sample. K+a galaxies occupy the brightest tail of the luminosity distribution. They are as massive as quiescent galaxies and populate the green valley in the colour versus luminosity (or stellar mass) distribution. A small percentage (<8%) of these galaxies have radio and/or X-ray counterparts (implying an upper limit to the SFR of ~8Msun/yr). Over the entire redshift range explored, the class of k+a galaxies is morphologically a heterogeneous population with a similar incidence of bulge-dominated and disky galaxies. This distribution does not vary with the strength of the Hdelt...
12. zCOSMOS 10k-bright spectroscopic sample: exploring mass and environment dependence in early-type galaxies
Moresco, M; Cimatti, A; Zamorani, G; Mignoli, M; Di Cesare, S; Bolzonella, M; Zucca, E; Lilly, S; Kovac, K; Scodeggio, M; Cassata, P; Tasca, L; Vergani, D; Halliday, C; Carollo, M; Contini, T; Kneib, J -P; Le Fèvre, O; Mainieri, V; Renzini, A; Bardelli, S; Bongiorno, A; Caputi, K; Coppa, G; Cucciati, O; de la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Knobel, C; Lamareille, F; Le Borgne, J F; Le Brun, V; Maier, C; Pello, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Silverman, J D; Tanaka, M; Tresse, L; Abbas, U; Bottini, D; Cappi, A; Guzzo, L; Koekemoer, A M; Leauthaud, A; Maccagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Nair, P; Oesch, P; Porciani, C; Scaramella, R; Scarlata, C; Scoville, N
2010-01-01
We present the analysis of the U-V rest-frame color distribution and some spectral features as a function of mass and environment for two sample of early-type galaxies up to z=1 extracted from the zCOSMOS spectroscopic survey. The first sample ("red galaxies") is defined with a photometric classification, while the second ("ETGs") by combining morphological, photometric, and spectroscopic properties to obtain a more reliable sample. We find that the color distribution of red galaxies is not strongly dependent on environment for all mass bins, with galaxies in overdense regions redder than galaxies in underdense regions with a difference of 0.027\\pm0.008 mag. The dependence on mass is far more significant, with average colors of massive galaxies redder by 0.093\\pm0.007 mag than low-mass galaxies throughout the entire redshift range. We study the color-mass relation, finding a mean slope 0.12\\pm0.005, while the color-environment relation is flatter, with a slope always smaller than 0.04. The spectral analysis t...
13. The impact of galaxy interactions on AGN activity in zCOSMOS
Silverman, J D; Jahnke, K; Andrae, R; Lilly, S; Elvis, M; Civano, F; Mainieri, V; Vignali, C; Zamorani, G; Nair, P; Fevre, O Le; de Ravel, L; Bardelli, S; Bongiorno, A; Bolzonella, M; Brusa, M; Cappelluti, N; Cappi, A; Caputi, K; Carollo, C M; Contini, T; Coppa, G; Cucciati, O; de la Torre, S; Franzetti, P; Garilli, B; Halliday, C; Hasinger, G; Iovino, A; Knobel, C; koekemoer, A; Kovac, K; Lamareille, F; Borgne, J -F Le; Brun, V Le; Maier, C; Mignoli, M; Pello, R; Montero, E Perez; Ricciardelli, E; Peng, Y; Scodeggio, M; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Zucca, E; Comastri, A; Finoguenov, A; Fu, H; Gilli, R; Hao, H; Ho, L; Salvato, M
2011-01-01
Close encounters between galaxies are expected to be a viable mechanism, as predicted by numerical simulations, by which accretion onto supermassive black holes can be initiated. To test this scenario, we construct a sample of 562 galaxies (M*>2.5x10^10 M_sun) in kinematic pairs over the redshift range 0.25 2x10^42 erg s^-1) detected by Chandra. We find a higher fraction of AGN in galaxies in pairs relative to isolated galaxies of similar stellar mass. Our result is primarily due to an enhancement of AGN activity, by a factor of 1.9 (observed) and 2.6 (intrinsic), for galaxies in pairs of projected separation less than 75 kpc and line-of-sight velocity offset less than 500 km s^-1. This study demonstrates that close kinematic pairs are conducive environments for black hole growth either indicating a causal physical connection or an inherent relation, such as, to enhanced star formation. In the Appendix, we describe a method to estimate the intrinsic fractions of galaxies (either in pairs or the field) hosting...
14. Oxygen abundances of zCOSMOS galaxies at z ~ 1.4 based on five lines and implications for the fundamental metallicity relation
Maier, Christian; Lilly, Simon J.; Ziegler, Bodo L.
2015-02-01
A relation between the stellar mass M and the gas-phase metallicity Z of galaxies, the MZR, is observed up to higher redshifts. It is a matter of debate, however, if the SFR is a second parameter in the MZR. To explore this issue at z > 1, we used VLT-SINFONI near-infrared (NIR) spectroscopy of eight zCOSMOS galaxies at 1.3 extinction corrected Hα measurements. We find that the MZR of these star-forming galaxies at z ~ 1.4 is lower than the local SDSS MZR by a factor of three to five, a larger change than reported in the literature using [NII]/Hα-based metallicities from individual and stacked spectra. Correcting N2-based O/Hs using recent results by Newman et al. (2014), also the larger FMOS sample at z ~ 1.4 of Zahid et al. (2014) shows a similar evolution of the MZR like the zCOSMOS objects. These observations seem also in agreement with a non-evolving FMR using the physically motivated formulation of the FMR from Lilly et al. (2013).
15. The Dependence of Star Formation Activity on Stellar Mass Surface Density and Sersic Index in zCOSMOS Galaxies at 0.5Galaxies at 0.04
Maier, C; Zamorani, G; Scodeggio, M; Lamareille, F; Contini, T; Sargent, M T; Scarlata, C; Oesch, P; Carollo, C M; Le Fèvre, O; Renzini, A; Kneib, J -P; Mainieri, V; Bardelli, S; Bolzonella, M; Bongiorno, A; Caputi, K; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Knobel, C; Kovac, K; Le Borgne, J F; Le Brun, V; Mignoli, M; Pellò, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Silverman, J D; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Zucca, E; Abbas, U; Bottini, D; Cappi, A; Cassata, P; Cimatti, A; Fumana, M; Guzzo, L; Halliday, C; Leauthaud, A; MacCagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Porciani, C; Pozzetti, L; Scaramella, R; Walcher, J
2009-01-01
In order to try to understand the internal evolution of galaxies and relate this to the global evolution of the galaxy population, we present a comparative study of the dependence of star formation rates on the average surface mass densities (SigmaM) of galaxies at 0.5 < z < 0.9 and 0.04zCOSMOS and SDSS surveys respectively. We derive star formation rates, stellar masses, and structural parameters in a consistent way for both samples, and apply them to samples that are complete down to the same stellar mass at both redshifts. We first show that the characteristic step-function dependence of median specific star formation rate (SSFR) on SigmaM in SDSS, seen by Brinchmann et al. (2004), is due to the changeover from predominantly disk galaxies to predominantly spheroidal galaxies at the surface mass density log(SigmaMchar) ~ 8.5 at which the SSFR is seen to drop. Turning to zCOSMOS, we find a similar shape for the median SSFR - SigmaM relation, but with median SSFR values that are...
16. The mass-metallicity and fundamental metallicity relations at z>2 using VLT and Subaru near-infrared spectroscopy of zCOSMOS galaxies
Maier, C; Ziegler, B; Contini, T; Montero, E Perez; Peng, Y; Balestra, I
2014-01-01
In the local universe, there is good evidence that, at a given stellar mass M, the gas-phase metallicity Z is anti-correlated with the star formation rate (SFR) of the galaxies. It has also been claimed that the resulting Z(M,SFR) relation is invariant with redshift - the so-called Fundamental Metallicity Relation (FMR). Given a number of difficulties in determining metallicities, especially at higher redshifts, the form of the Z(M,SFR) relation and whether it is really independent of redshift is still very controversial. To explore this issue at z>2, we used VLT-SINFONI and Subaru-MOIRCS near-infrared spectroscopy of 20 zCOSMOS-deep galaxies at 2.12 galaxies of a given mass have much higher SFRs than the local SDSS galaxies. We find that the zCOSMOS galaxies are consistent with a non-evolving FMR if we use the physically-motivated formulation of the Z(M,SFR) relation from Lilly et al. (2003), but not if we use the empirical formulation of Mannucci et al. (2010).
17. The zCOSMOS survey: the role of the environment in the evolution of the luminosity function of different galaxy types
Zucca, E; Bolzonella, M; Zamorani, G; Ilbert, O; Pozzetti, L; Mignoli, M; Kovac, K; Lilly, S; Tresse, L; Tasca, L; Cassata, P; Halliday, C; Vergani, D; Caputi, K; Carollo, C M; Contini, T; Kneib, J P; LeFevre, O; Mainieri, V; Renzini, A; Scodeggio, M; Bongiorno, A; Coppa, G; Cucciati, O; delaTorre, S; deRavel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Knobel, C; Lamareille, F; LeBorgne, J F; Le Brun, V; Maier, C; Pello, R; Peng, Y; Pérez-Montero, E; Ricciardelli, E; Silverman, J D; Tanaka, M; Abbas, U; Bottini, D; Cappi, A; Cimatti, A; Guzzo, L; Koekemoer, A M; Leauthaud, A; MacCagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Moresco, M; Oesch, P; Porciani, C; Scaramella, R; Arnouts, S; Aussel, H; Capak, P; Kartaltepe, J; Salvato, M; Sanders, D; Scoville, N; Taniguchi, Y; Thompson, D
2009-01-01
(Abridged) We studied the evolution in the B band luminosity function to z~1 in the zCOSMOS 10k sample, for which both accurate galaxy classifications and a detailed description of the local density field are available. The global LF exhibits a brightening of ~0.7 mag in M* from z~0.2 to z~0.9. At low z, late types dominate at faint magnitudes, while the bright end is populated mainly by early types. At higher z, late-type galaxies evolve significantly and, at z~1, the contribution from the various types to the bright end of the LF is comparable. The evolution for early types is in both luminosity and normalization. A similar behaviour is exhibited by late types, but with an opposite trend for the normalization. Studying the role of the environment, we find that the global LF of galaxies in overdense regions has always a brighter M* and a flatter slope. In low density environments, the main contribution to the LF is from blue galaxies, while for high density environments there is an important contribution fro...
18. The Mass-Metallicity and Fundamental Metallicity Relations at z > 2 Using Very Large Telescope and Subaru Near-infrared Spectroscopy of zCOSMOS Galaxies
Maier, C.; Lilly, S. J.; Ziegler, B. L.; Contini, T.; Pérez Montero, E.; Peng, Y.; Balestra, I.
2014-09-01
In the local universe, there is good evidence that, at a given stellar mass M, the gas-phase metallicity Z is anti-correlated with the star formation rate (SFR) of the galaxies. It has also been claimed that the resulting Z(M, SFR) relation is invariant with redshift—the so-called "fundamental metallicity relation" (FMR). Given a number of difficulties in determining metallicities, especially at higher redshifts, the form of the Z(M, SFR) relation and whether it is really independent of redshift is still very controversial. To explore this issue at z > 2, we used VLT-SINFONI and Subaru-MOIRCS near-infrared spectroscopy of 20 zCOSMOS-deep galaxies at 2.1 extinction corrected Hα measurements. We find that the mass-metallicity relation (MZR) of these star-forming galaxies at z ≈ 2.3 is lower than the local Sloan Digital Sky Survey (SDSS) MZR by a factor of three to five, a larger change than found by Erb et al. using [N II]/Hα-based metallicities from stacked spectra. We discuss how the different selections of the samples and metallicity calibrations used may be responsible for this discrepancy. The galaxies show direct evidence that the SFR is still a second parameter in the MZR at these redshifts. However, determining whether the Z(M, SFR) relation is invariant with epoch depends on the choice of extrapolation used from local samples, because z > 2 galaxies of a given mass have much higher SFRs than the local SDSS galaxies. We find that the zCOSMOS galaxies are consistent with a non-evolving FMR if we use the physically motivated formulation of the Z(M, SFR) relation from Lilly et al., but not if we use the empirical formulation of Mannucci et al. AND SUBARU
19. Mass and environment as drivers of galaxy evolution in SDSS and zCOSMOS and the origin of the Schechter function
Peng, Y; Kovac, K; Bolzonella, M; Pozzetti, L; Renzini, A; Zamorani, G; Ilbert, O; Knobel, C; Iovino, A; Maier, C; Cucciati, O; Tasca, L; Carollo, C M; Silverman, J; Kampczyk, P; de Ravel, L; Sanders, D; Contini, T; Mainieri, V; Scodeggio, M; Kneib, J -P; Le Fèvre, O; Bardelli, S; Bongiorno, A; Caputi, K; Coppa, G; de la Torre, S; Franzetti, P; Garilli, B; Lamareille, F; Le Borgne, J F; Le Brun, V; Mignoli, M; Montero, E Perez; Pello, R; Ricciardelli, E; Tanaka, M; Tresse, L; Vergani, D; Welikala, N; Zucca, E; Oesch, P; Abbas, U; Barnes, L; Bordoloi, R; Bottini, D; Cappi, A; Cassata, P; Cimatti, A; Fumana, M; Hasinger, G; Koekemoer, A M; Leauthaud, A; Maccagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Nair, P; Porciani, C; Presotto, V; Scaramella, R
2010-01-01
We explore the inter-relationships between mass, star-formation rate and environment in the SDSS, zCOSMOS and other surveys. The differential effects of mass and environment are completely separable to z ~ 1, indicating that two distinct processes are operating, "mass-quenching" and "environment-quenching". Environment-quenching, at fixed over-density, evidently does not change with epoch to z ~ 1, suggesting that it occurs as large-scale structure develops in the Universe. The observed constancy of the mass-function shape for star-forming galaxies, demands that the mass-quenching of galaxies around and above M*, must be proportional to their star-formation rates at all z < 2. We postulate that this simple mass-quenching law also holds over a much broader range of stellar mass and epoch. These two simple quenching processes, plus some additional quenching due to merging, then naturally produce (a) a quasi-static Schechter mass function for star-forming galaxies with a value of M* that is set by the proport...
20. Oxygen abundances of zCOSMOS galaxies at z~1.4 based on five lines and implications for the fundamental metallicity relation
Maier, C; Ziegler, B L
2014-01-01
A relation between the stellar mass M and the gas-phase metallicity Z of galaxies, the MZR, is observed up to higher redshifts. It is a matter of debate, however, if the SFR is a second parameter in the MZR. To explore this issue at z > 1, we used VLT-SINFONI near-infrared (NIR) spectroscopy of eight zCOSMOS galaxies at 1.3 < z < 1.4 to measure the strengths of four emission lines: Hbeta, [OIII]lambda5007, Halpha, and [NII]lambda6584, additional to [OII]lambda3727 measured from VIMOS. We derive reliable O/H metallicities based on five lines, and also SFRs from extinction corrected Halpha measurements. We find that the MZR of these star-forming galaxies at z~1.4 is lower than the local SDSS MZR by a factor of three to five, a larger change than reported in the literature using [NII]/Halpha-based metallicities from individual and stacked spectra. Correcting N2-based O/Hs using recent results by Newman et al. (2014), also the larger FMOS sample at z~1.4 of Zahid et al. (2014) shows a similar evolution of t...
1. Mass and Environment as Drivers of Galaxy Evolution in SDSS and zCOSMOS and the Origin of the Schechter Function
Peng, Ying-jie; Lilly, Simon J.; Kovač, Katarina; Bolzonella, Micol; Pozzetti, Lucia; Renzini, Alvio; Zamorani, Gianni; Ilbert, Olivier; Knobel, Christian; Iovino, Angela; Maier, Christian; Cucciati, Olga; Tasca, Lidia; Carollo, C. Marcella; Silverman, John; Kampczyk, Pawel; de Ravel, Loic; Sanders, David; Scoville, Nicholas; Contini, Thierry; Mainieri, Vincenzo; Scodeggio, Marco; Kneib, Jean-Paul; Le Fèvre, Olivier; Bardelli, Sandro; Bongiorno, Angela; Caputi, Karina; Coppa, Graziano; de la Torre, Sylvain; Franzetti, Paolo; Garilli, Bianca; Lamareille, Fabrice; Le Borgne, Jean-Francois; Le Brun, Vincent; Mignoli, Marco; Perez Montero, Enrique; Pello, Roser; Ricciardelli, Elena; Tanaka, Masayuki; Tresse, Laurence; Vergani, Daniela; Welikala, Niraj; Zucca, Elena; Oesch, Pascal; Abbas, Ummi; Barnes, Luke; Bordoloi, Rongmon; Bottini, Dario; Cappi, Alberto; Cassata, Paolo; Cimatti, Andrea; Fumana, Marco; Hasinger, Gunther; Koekemoer, Anton; Leauthaud, Alexei; Maccagni, Dario; Marinoni, Christian; McCracken, Henry; Memeo, Pierdomenico; Meneux, Baptiste; Nair, Preethi; Porciani, Cristiano; Presotto, Valentina; Scaramella, Roberto
2010-09-01
We explore the simple inter-relationships between mass, star formation rate, and environment in the SDSS, zCOSMOS, and other deep surveys. We take a purely empirical approach in identifying those features of galaxy evolution that are demanded by the data and then explore the analytic consequences of these. We show that the differential effects of mass and environment are completely separable to z ~ 1, leading to the idea of two distinct processes of "mass quenching" and "environment quenching." The effect of environment quenching, at fixed over-density, evidently does not change with epoch to z ~ 1 in zCOSMOS, suggesting that the environment quenching occurs as large-scale structure develops in the universe, probably through the cessation of star formation in 30%-70% of satellite galaxies. In contrast, mass quenching appears to be a more dynamic process, governed by a quenching rate. We show that the observed constancy of the Schechter M* and αs for star-forming galaxies demands that the quenching of galaxies around and above M* must follow a rate that is statistically proportional to their star formation rates (or closely mimic such a dependence). We then postulate that this simple mass-quenching law in fact holds over a much broader range of stellar mass (2 dex) and cosmic time. We show that the combination of these two quenching processes, plus some additional quenching due to merging naturally produces (1) a quasi-static single Schechter mass function for star-forming galaxies with an exponential cutoff at a value M* that is set uniquely by the constant of proportionality between the star formation and mass quenching rates and (2) a double Schechter function for passive galaxies with two components. The dominant component (at high masses) is produced by mass quenching and has exactly the same M* as the star-forming galaxies but a faint end slope that differs by Δαs ~ 1. The other component is produced by environment effects and has the same M* and αs as the
2. The Smallest AGN Host Galaxies
Greene, J E; Ho, L C
2005-01-01
We describe our efforts to study dwarf galaxies with active nuclei, whose black holes, with masses < 10^6 M_sun, provide the best current observational constraints on the mass distribution of primordial seed black holes. Although these low-mass galaxies do not necessarily contain classical bulges, Barth, Greene, & Ho (2005) show that their stellar velocity dispersions and black hole masses obey the same relation as more massive systems. In order to characterize the properties of the dwarf hosts without the glare of the active nucleus, we have compiled a complementary sample of narrow-line active galaxies with low-mass hosts. The host galaxy properties, both their structures and stellar populations, are consistent with the general properties of low-mass, blue galaxies from Sloan. The black holes in these galaxies are probably radiating close to their Eddington limits, suggesting we may have found Type 2 analogues of narrow-line Seyfert 1 galaxies.
3. The mass-metallicity and fundamental metallicity relations at z > 2 using very large telescope and Subaru near-infrared spectroscopy of zCOSMOS galaxies
Maier, C.; Ziegler, B. L. [Department of Astrophysics, University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna (Austria); Lilly, S. J.; Peng, Y. [Institute of Astronomy, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Contini, T. [Institut de Recherche en Astrophysique et Planétologie, CNRS, 14 avenue Édouard Belin, F-31400 Toulouse (France); Pérez Montero, E. [Instituto de Astrofísica de Andalucia, CSIC, Apartado de Correos 3004, E-18080 Granada (Spain); Balestra, I., E-mail: [email protected] [Max-Planck-Institut für Extraterrestrische Physik, Postfach 1312, Giessenbachstrasse, D-85741 Garching b. München (Germany)
2014-09-01
In the local universe, there is good evidence that, at a given stellar mass M, the gas-phase metallicity Z is anti-correlated with the star formation rate (SFR) of the galaxies. It has also been claimed that the resulting Z(M, SFR) relation is invariant with redshift—the so-called 'fundamental metallicity relation' (FMR). Given a number of difficulties in determining metallicities, especially at higher redshifts, the form of the Z(M, SFR) relation and whether it is really independent of redshift is still very controversial. To explore this issue at z > 2, we used VLT-SINFONI and Subaru-MOIRCS near-infrared spectroscopy of 20 zCOSMOS-deep galaxies at 2.1 < z < 2.5 to measure the strengths of up to five emission lines: [O II] λ3727, Hβ, [O III] λ5007, Hα, and [N II] λ6584. This near-infrared spectroscopy enables us to derive O/H metallicities, and also SFRs from extinction corrected Hα measurements. We find that the mass-metallicity relation (MZR) of these star-forming galaxies at z ≈ 2.3 is lower than the local Sloan Digital Sky Survey (SDSS) MZR by a factor of three to five, a larger change than found by Erb et al. using [N II]/Hα-based metallicities from stacked spectra. We discuss how the different selections of the samples and metallicity calibrations used may be responsible for this discrepancy. The galaxies show direct evidence that the SFR is still a second parameter in the MZR at these redshifts. However, determining whether the Z(M, SFR) relation is invariant with epoch depends on the choice of extrapolation used from local samples, because z > 2 galaxies of a given mass have much higher SFRs than the local SDSS galaxies. We find that the zCOSMOS galaxies are consistent with a non-evolving FMR if we use the physically motivated formulation of the Z(M, SFR) relation from Lilly et al., but not if we use the empirical formulation of Mannucci et al.
4. The 10k zCOSMOS : Morphological transformation of galaxies in the Group Environment since z ~1
Kovač, K.; Lilly, S. J.; Knobel, C.; Bolzonella, M.; Iovino, A.; Carollo, C. M.; Scarlata, C.; Sargent, M.; Cucciati, O.; Zamorani, G.; Pozzetti, L.; Tasca, L. A. M.; Scodeggio, M.; Kampczyk, P.; Peng, Y.; Oesch, P.; Zucca, E.; Finoguenov, A.; Contini, T.; Kneib, J.-P.; Le Fèvre, O.; Mainieri, V.; Renzini, A.; Bardelli, S.; Bongiorno, A.; Caputi, K.; Coppa, G.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Lamareille, F.; Le Borgne, J.-F.; Le Brun, V.; Maier, C.; Mignoli, M.; Pello, R.; Perez Montero, E.; Ricciardelli, E.; Silverman, J. D.; Tanaka, M.; Tresse, L.; Vergani, D.; Abbas, U.; Bottini, D.; Cappi, A.; Cassata, P.; Cimatti, A.; Fumana, M.; Guzzo, L.; Koekemoer, A. M.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Meneux, B.; Porciani, C.; Scaramella, R.; Scoville, N. Z.
2010-01-01
We study the evolution of galaxies inside and outside of the group environment since z = 1 using a large well-defined set of groups and galaxies from the zCOSMOS-bright redshift survey in the COSMOS field. The fraction of galaxies with early-type morphologies increases monotonically with MB luminosi
5. The zCOSMOS redshift survey: the three-dimensional classification cube and bimodality in galaxy physical properties
Mignoli, M; Scodeggio, M; Cimatti, A; Halliday, C; Lilly, S J; Pozzetti, L; Vergani, D; Carollo, C M; Contini, T; Le Fèvre, O; Mainieri, V; Renzini, A; Bardelli, S; Bolzonella, M; Bongiorno, A; Caputi, K; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Kneib, J -P; Knobel, C; Kovac, K; Lamareille, F; Le Borgne, J F; Le Brun, V; Maier, C; Pellò, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Scarlata, C; Silverman, J D; Tanaka, M; Tasca, L; Tresse, L; Zucca, E; Abbas, U; Bottini, D; Capak, P; Cappi, A; Cassata, P; Fumana, M; Guzzo, L; Leauthaud, A; MacCagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Scaramella, R; Scoville, N
2008-01-01
Aims. We investigate the relationships between three main optical galaxy observables (spectral properties, colours, and morphology), exploiting the data set provided by the COSMOS/zCOSMOS survey. The purpose of this paper is to define a simple galaxy classification cube, using a carefully selected sample of around 1000 galaxies. Methods. Using medium resolution spectra of the first 1k zCOSMOS-bright sample, optical photometry from the Subaru/COSMOS observations, and morphological measurements derived from ACS imaging, we analyze the properties of the galaxy population out to z~1. Applying three straightforward classification schemes (spectral, photometric, and morphological), we identify two main galaxy types, which appear to be linked to the bimodality of galaxy population. The three parametric classifications constitute the axes of a "classification cube". Results. A very good agreement exists between the classification from spectral data (quiescent/star-forming galaxies) and that based on colours (red/blue...
6. The zCOSMOS redshift survey : The three-dimensional classification cube and bimodality in galaxy physical properties
Mignoli, M.; Zamorani, G.; Scodeggio, M.; Cimatti, A.; Halliday, C.; Lilly, S. J.; Pozzetti, L.; Vergani, D.; Carollo, C. M.; Contini, T.; Le Fevre, O.; Mainieri, V.; Renzini, A.; Bardelli, S.; Bolzonella, M.; Bongiorno, A.; Caputi, K.; Coppa, G.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Kneib, J. -P.; Knobel, C.; Kovac, K.; Lamareille, F.; Le Borgne, J. -F.; Le Brun, V.; Maier, C.; Pello, R.; Peng, Y.; Montero, E. Perez; Ricciardelli, E.; Scarlata, C.; Silverman, J. D.; Tanaka, M.; Tasca, L.; Tresse, L.; Zucca, E.; Abbas, U.; Bottini, D.; Capak, P.; Cappi, A.; Cassata, P.; Fumana, M.; Guzzo, L.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Meneux, B.; Oesch, P.; Porciani, C.; Scaramella, R.; Scoville, N.
2009-01-01
Aims: We investigate the relationships between three main optical galaxy observables (spectral properties, colors, and morphology), exploiting the data set provided by the COSMOS/zCOSMOS survey. The purpose of this paper is to define a simple galaxy classification cube, with a carefully selected sam
7. The Environments of Active Galactic Nuclei within the zCOSMOS Density Field
Silverman, J D; Knobel, C; Lilly, S; Bolzonella, M; Lamareille, F; Mainieri, V; Brusa, M; Cappelluti, N; Peng, Y; Hasinger, G; Zamorani, G; Scodeggio, M; Contini, T; Carollo, C M; Jahnke, K; Kneib, J -P; Le Fèvre, O; Bardelli, S; Bongiorno, A; Brunner, H; Caputi, K; Civano, F; Comastri, A; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Elvis, M; Finoguenov, A; Fiore, F; Franzetti, P; Garilli, B; Gilli, R; Griffiths, R; Iovino, A; Kampczyk, P; Le Borgne, J F; Le Brun, V; Maier, C; Mignoli, M; Pellò, R; Montero, E Perez; Ricciardelli, E; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Vignali, C; Zucca, E; Bottini, D; Cappi, A; Cassata, P; Fumana, M; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Salvato, M
2008-01-01
The impact of environment on AGN activity up to z~1 is assessed by utilizing a mass-selected sample of galaxies from the 10k catalog of the zCOSMOS spectroscopic redshift survey. We identify 147 AGN by their X-ray emission as detected by XMM-Newton from a parent sample of 7234 galaxies. We measure the fraction of galaxies with stellar mass M_*>2.5x10^10 Msun that host an AGN as a function of local overdensity using the 5th, 10th and 20th nearest neighbors that cover a range of physical scales (~1-4 Mpc). Overall, we find that AGNs prefer to reside in environments equivalent to massive galaxies with substantial levels of star formation. Specifically, AGNs with host masses between 0.25-1x10^11 Msun span the full range of environments (i.e., field-to-group) exhibited by galaxies of the same mass and rest-frame color or specific star formation rate. Host galaxies having M_*>10^11 Msun clearly illustrate the association with star formation since they are predominantly bluer than the underlying galaxy population an...
8. Host Galaxy Identification for Supernova Surveys
Gupta, Ravi R.; Kuhlmann, Steve; Kovacs, Eve; Spinka, Harold; Kessler, Richard; Goldstein, Daniel A.; Liotine, Camille; Pomian, Katarzyna; D’Andrea, Chris B.; Sullivan, Mark; Carretero, Jorge; Castander, Francisco J.; Nichol, Robert C.; Finley, David A.; Fischer, John A.; Foley, Ryan J.; Kim, Alex G.; Papadopoulos, Andreas; Sako, Masao; Scolnic, Daniel M.; Smith, Mathew; Tucker, Brad E.; Uddin, Syed; Wolf, Rachel C.; Yuan, Fang; Abbott, Tim M. C.; Abdalla, Filipe B.; Benoit-Lévy, Aurélien; Bertin, Emmanuel; Brooks, David; Rosell, Aurelio Carnero; Kind, Matias Carrasco; Cunha, Carlos E.; Costa, Luiz N. da; Desai, Shantanu; Doel, Peter; Eifler, Tim F.; Evrard, August E.; Flaugher, Brenna; Fosalba, Pablo; Gaztañaga, Enrique; Gruen, Daniel; Gruendl, Robert; James, David J.; Kuehn, Kyler; Kuropatkin, Nikolay; Maia, Marcio A. G.; Marshall, Jennifer L.; Miquel, Ramon; Plazas, Andrés A.; Romer, A. Kathy; Sánchez, Eusebio; Schubnell, Michael; Sevilla-Noarbe, Ignacio; Sobreira, Flávia; Suchyta, Eric; Swanson, Molly E. C.; Tarle, Gregory; Walker, Alistair R.; Wester, William
2016-11-08
Host galaxy identification is a crucial step for modern supernova (SN) surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope (LSST), which will discover SNe by the thousands. Spectroscopic resources are limited, so in the absence of real-time SN spectra these surveys must rely on host galaxy spectra to obtain accurate redshifts for the Hubble diagram and to improve photometric classification of SNe. In addition, SN luminosities are known to correlate with host-galaxy properties. Therefore, reliable identification of host galaxies is essential for cosmology and SN science. We simulate SN events and their locations within their host galaxies to develop and test methods for matching SNe to their hosts. We use both real and simulated galaxy catalog data from the Advanced Camera for Surveys General Catalog and MICECATv2.0, respectively. We also incorporate "hostless" SNe residing in undetected faint hosts into our analysis, with an assumed hostless rate of 5%. Our fully automated algorithm is run on catalog data and matches SNe to their hosts with 91% accuracy. We find that including a machine learning component, run after the initial matching algorithm, improves the accuracy (purity) of the matching to 97% with a 2% cost in efficiency (true positive rate). Although the exact results are dependent on the details of the survey and the galaxy catalogs used, the method of identifying host galaxies we outline here can be applied to any transient survey.
9. Host Galaxy Identification for Supernova Surveys
Gupta, Ravi R.; Kuhlmann, Steve; Kovacs, Eve; Spinka, Harold; Kessler, Richard; Goldstein, Daniel A.; Liotine, Camille; Pomian, Katarzyna; D'Andrea, Chris B.; Sullivan, Mark; Carretero, Jorge; Castander, Francisco J.; Nichol, Robert C.; Finley, David A.; Fischer, John A.; Foley, Ryan J.; Kim, Alex G.; Papadopoulos, Andreas; Sako, Masao; Scolnic, Daniel M.; Smith, Mathew; Tucker, Brad E.; Uddin, Syed; Wolf, Rachel C.; Yuan, Fang; Abbott, Tim M. C.; Abdalla, Filipe B.; Benoit-Lévy, Aurélien; Bertin, Emmanuel; Brooks, David; Carnero Rosell, Aurelio; Carrasco Kind, Matias; Cunha, Carlos E.; da Costa, Luiz N.; Desai, Shantanu; Doel, Peter; Eifler, Tim F.; Evrard, August E.; Flaugher, Brenna; Fosalba, Pablo; Gaztañaga, Enrique; Gruen, Daniel; Gruendl, Robert; James, David J.; Kuehn, Kyler; Kuropatkin, Nikolay; Maia, Marcio A. G.; Marshall, Jennifer L.; Miquel, Ramon; Plazas, Andrés A.; Romer, A. Kathy; Sánchez, Eusebio; Schubnell, Michael; Sevilla-Noarbe, Ignacio; Sobreira, Flávia; Suchyta, Eric; Swanson, Molly E. C.; Tarle, Gregory; Walker, Alistair R.; Wester, William
2016-12-01
Host galaxy identification is a crucial step for modern supernova (SN) surveys such as the Dark Energy Survey and the Large Synoptic Survey Telescope, which will discover SNe by the thousands. Spectroscopic resources are limited, and so in the absence of real-time SN spectra these surveys must rely on host galaxy spectra to obtain accurate redshifts for the Hubble diagram and to improve photometric classification of SNe. In addition, SN luminosities are known to correlate with host-galaxy properties. Therefore, reliable identification of host galaxies is essential for cosmology and SN science. We simulate SN events and their locations within their host galaxies to develop and test methods for matching SNe to their hosts. We use both real and simulated galaxy catalog data from the Advanced Camera for Surveys General Catalog and MICECATv2.0, respectively. We also incorporate “hostless” SNe residing in undetected faint hosts into our analysis, with an assumed hostless rate of 5%. Our fully automated algorithm is run on catalog data and matches SNe to their hosts with 91% accuracy. We find that including a machine learning component, run after the initial matching algorithm, improves the accuracy (purity) of the matching to 97% with a 2% cost in efficiency (true positive rate). Although the exact results are dependent on the details of the survey and the galaxy catalogs used, the method of identifying host galaxies we outline here can be applied to any transient survey.
10. Host Galaxy Identification for Supernova Surveys
Gupta, Ravi R.; et al.
2016-04-20
Host galaxy identification is a crucial step for modern supernova (SN) surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope (LSST), which will discover SNe by the thousands. Spectroscopic resources are limited, so in the absence of real-time SN spectra these surveys must rely on host galaxy spectra to obtain accurate redshifts for the Hubble diagram and to improve photometric classification of SNe. In addition, SN luminosities are known to correlate with host-galaxy properties. Therefore, reliable identification of host galaxies is essential for cosmology and SN science. We simulate SN events and their locations within their host galaxies to develop and test methods for matching SNe to their hosts. We use both real and simulated galaxy catalog data from the Advanced Camera for Surveys General Catalog and MICECATv2.0, respectively. We also incorporate "hostless" SNe residing in undetected faint hosts into our analysis, with an assumed hostless rate of 5%. Our fully automated algorithm is run on catalog data and matches SNe to their hosts with 91% accuracy. We find that including a machine learning component, run after the initial matching algorithm, improves the accuracy (purity) of the matching to 97% with a 2% cost in efficiency (true positive rate). Although the exact results are dependent on the details of the survey and the galaxy catalogs used, the method of identifying host galaxies we outline here can be applied to any transient survey.
11. AGN Host Galaxy Properties And Mass Function
Bongiorno, Angela
2016-10-01
Supermassive black hole growth, nuclear activity, and galaxy evolution have been found to be closely related. In the context of AGN-galaxy coevolution, I will discuss about the relation found between the host galaxy properties and the central BH and I will present the latest determination of the host galaxy stellar mass function (HGMF), and the specific accretion rate distribution function (SARDF), derived from the XMM-COSMOS sample up to z˜2.5, with particular focus on AGN feedback as possible responsible mechanism for galaxy quenching.
12. zCOSMOS : A large VLT/VIMOS redshift survey covering 0
Lilly, S. J.; Le Fevre, O.; Renzini, A.; Zamorani, G.; Scodeggio, M.; Contini, T.; Carollo, C. M.; Hasinger, G.; Kneib, J.-P.; Iovino, A.; Le Brun, V.; Maier, C.; Mainieri, V.; Mignoli, M.; Silverman, J.; Tasca, L. A. M.; Bolzonella, M.; Bongiorno, A.; Bottini, D.; Capak, P.; Caputi, K.; Cimatti, A.; Cucciati, O.; Daddi, E.; Feldmann, R.; Franzetti, P.; Garilli, B.; Guzzo, L.; Ilbert, O.; Kampczyk, P.; Kovac, K.; Lamareille, F.; Leauthaud, A.; Le Borgne, J.-F.; McCracken, H. J.; Marinoni, C.; Pello, R.; Ricciardelli, E.; Scarlata, C.; Vergani, D.; Sanders, D. B.; Schinnerer, E.; Scoville, N.; Taniguchi, Y.; Arnouts, S.; Aussel, H.; Bardelli, S.; Brusa, M.; Cappi, A.; Ciliegi, P.; Finoguenov, A.; Foucaud, S.; Franceschini, R.; Halliday, C.; Impey, C.; Knobel, C.; Koekemoer, A.; Kurk, J.; Maccagni, D.; Maddox, S.; Marano, B.; Marconi, G.; Meneux, B.; Mobasher, B.; Moreau, C.; Peacock, J. A.; Porciani, C.; Pozzetti, L.; Scaramella, R.; Schiminovich, D.; Shopbell, P.; Smail, I.; Thompson, D.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Zucca, E.
2007-01-01
zCOSMOS is a large-redshift survey that is being undertaken in the COSMOS field using 600 hr of observation with the VIMOS spectrograph on the 8mVLT. The survey is designed to characterize the environments of COSMOS galaxies from the 100 kpc scales of galaxy groups up to the 100 Mpc scale of the cos
13. AGN Host Galaxy Properties and Mass Function
Bongiorno, Angela
2016-01-01
Supermassive black hole growth, nuclear activity, and galaxy evolution have been found to be closely related. In the context of AGN-galaxy coevolution, I will discuss about the relation found between the host galaxy properties and the central BH and I will present the latest determination of the host galaxy stellar mass function (HGMF), and the specific accretion rate distribution function (SARDF), derived from the XMM-COSMOS sample up to z∼2.5, with particular focus on AGN feedback as possib...
14. Host Galaxy Identification for Supernova Surveys
Gupta, Ravi R; Kovacs, Eve; Spinka, Harold; Kessler, Richard; Goldstein, Daniel A; Liotine, Camille; Pomian, Katarzyna; D'Andrea, Chris B; Sullivan, Mark; Carretero, Jorge; Castander, Francisco J; Nichol, Robert C; Finley, David A; Fischer, John A; Foley, Ryan J; Kim, Alex G; Papadopoulos, Andreas; Sako, Masao; Scolnic, Daniel M; Smith, Mathew; Tucker, Brad E; Uddin, Syed; Wolf, Rachel C; Yuan, Fang; Abbott, Tim M C; Abdalla, Filipe B; Benoit-Levy, Aurelien; Bertin, Emmanuel; Brooks, David; Rosell, Aurelio Carnero; Kind, Matias Carrasco; Cunha, Carlos E; da Costa, Luiz N; Desai, Shantanu; Doel, Peter; Eifler, Tim F; Evrard, August E; Flaugher, Brenna; Fosalba, Pablo; Gaztanaga, Enrique; Gruen, Daniel; Gruendl, Robert; James, David J; Kuehn, Kyler; Kuropatkin, Nikolay; Maia, Marcio A G; Marshall, Jennifer L; Miquel, Ramon; Plazas, Andres A; Romer, A Kathy; Sanchez, Eusebio; Schubnell, Michael; Sevilla-Noarbe, Ignacio; Sobreira, Flavia; Suchyta, Eric; Swanson, Molly E C; Tarle, Gregory; Walker, Alistair R; Wester, William
2016-01-01
Host galaxy identification is a crucial step for modern supernova (SN) surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope (LSST), which will discover SNe by the thousands. Spectroscopic resources are limited, so in the absence of real-time SN spectra these surveys must rely on host galaxy spectra to obtain accurate redshifts for the Hubble diagram and to improve photometric classification of SNe. In addition, SN luminosities are known to correlate with host-galaxy properties. Therefore, reliable identification of host galaxies is essential for cosmology and SN science. We simulate SN events and their locations within their host galaxies to develop and test methods for matching SNe to their hosts. We use both real and simulated galaxy catalog data from the Advanced Camera for Surveys General Catalog and MICECATv2.0, respectively. We also incorporate "hostless" SNe residing in undetected faint hosts into our analysis, with an assumed hostless rate of 5%. Our fully automated alg...
15. Study of GRBs Hosts Galaxies Vicinity Properties
Bernal, S.; Vasquez, N.; Hoyle, F.
2017-07-01
The study of GRBs host galaxies and its vicinity could provide constrains on the progenitor and an opportunity to use these violent explosions to characterize the nature of the highredshift universe. Studies of GRB host galaxies reveal a population of starforming galaxies with great diversity, spanning a wide range of masses, star formation rate, and redshifts. In order to study the galactic ambient of GRBs we used the S. Savaglio catalog from 2015 where 245 GRBs are listed with RA-Dec position and z. We choose 22 GRBs Hosts galaxies from Savaglio catalog and SDSS DR12, with z range 0work we provide characteristics on the regions for future works related with highredsift universe that using the GRBs.
16. The host galaxy of GRB 990712
Christensen, L.; Hjorth, J.; Gorosabel, J.
2004-01-01
We present a comprehensive study of the z = 0.43 host galaxy of GRB 990712, involving ground-based photometry, spectroscopy, and HST imaging. The broad-band UBVRIJHKs photometry is used to determine the global spectral energy distribution (SED) of the host galaxy. Comparison with that of known...... galaxy types shows that the host is similar to a moderately kreddened starburst galaxy with a young stellar population. The estimated internal extinction in the host is A(V) = 0.15 +/- 0.1 and the star-formation rate (SFR) from the UV continuum is 1.3 +/- 0.3 M-circle dot yr(-1) (not corrected...... for the effects of extinction). Other galaxy template spectra than starbursts failed to reproduce the observed SED. We also present VLT spectra leading to the detection of Halpha from the GRB host galaxy. A SFR of 2.8 +/- 0.7 M-circle dot yr(-1) is inferred from the Halpha line flux, and the presence of a young...
17. The Environments of Active Galactic Nuclei within the zCOSMOS Density Field
Silverman, J. D.; Kovac, K.; Knobel, C.; Lilly, S.; Bolzonella, M.; Lamareille, F.; Mainieri, V.; Brusa, M.; Cappelluti, N.; Peng, Y.; Hasinger, G.; Zamorani, G.; Scodeggio, M.; Contini, T.; Carollo, C. M.; Jahnke, K.; Kneib, J. -P.; Le Fevre, O.; Bardelli, S.; Bongiorno, A.; Brunner, H.; Caputi, K.; Civano, F.; Comastri, A.; Coppa, G.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Elvis, M.; Finoguenov, A.; Fiore, F.; Franzetti, P.; Garilli, B.; Gilli, R.; Griffiths, R.; Iovino, A.; Kampczyk, P.; Koekemoer, A.; Le Borgne, J. -F.; Le Brun, V.; Maier, C.; Mignoli, M.; Pello, R.; Montero, E. Perez; Ricciardelli, E.; Tanaka, M.; Tasca, L.; Tresse, L.; Vergani, D.; Vignali, C.; Zucca, E.; Bottini, D.; Cappi, A.; Cassata, P.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Meneux, B.; Oesch, P.; Porciani, C.; Salvato, M.
2009-01-01
The impact of environment on active galactic nucleus (AGN) activity up to z ~ 1 is assessed by utilizing a mass-selected sample of galaxies from the 10k catalog of the zCOSMOS spectroscopic redshift survey. We identify 147 AGN by their X-ray emission as detected by XMM-Newton from a parent sample of
18. Tidal Disruption Events Prefer Unusual Host Galaxies
French, K Decker; Zabludoff, Ann
2016-01-01
Tidal Disruption Events (TDEs) are transient events observed when a star passes close enough to a supermassive black hole to be tidally destroyed. Many TDE candidates have been discovered in host galaxies whose spectra have weak or no line emission yet strong Balmer line absorption, indicating a period of intense star formation that has recently ended. As such, TDE host galaxies fall into the rare class of quiescent Balmer-strong galaxies. Here, we quantify the fraction of galaxies in the Sloan Digital Sky Survey (SDSS) with spectral properties like those of TDE hosts, determining the extent to which TDEs are over-represented in such galaxies. Galaxies whose spectra have Balmer absorption H$\\delta_{\\rm A}$ $-$ $\\sigma$(H$\\delta_{\\rm A}$) $>$ 4 \\AA\\ (where $\\sigma$(H$\\delta_{\\rm A}$) is the error in the Lick H$\\delta_{\\rm A}$ index) and H$\\alpha$ emission EW 1.31 \\AA\\ and H\\alpha EW 80\\times enhancement in such hosts and providing an observational link between the \\gamma/X-ray-bright and optical/UV-br... 19. Spectroscopy of superluminous supernova host galaxies Leloudas, G.; Kruehler, T.; Schulze, S 2015-01-01 Superluminous supernovae (SLSNe) are very bright explosions that were only discovered recently and that show a preference for occurring in faint dwarf galaxies. Understanding why stellar evolution yields different types of stellar explosions in these environments is fundamental in order to both...... uncover the elusive progenitors of SLSNe and to study star formation in dwarf galaxies. In this paper, we present the first results of our project to study SUperluminous Supernova Host galaxIES, focusing on the sample for which we have obtained spectroscopy. We show that SLSNe-I and SLSNe-R (hydrogen... 20. In Search of Quasar Host Galaxies Young, Jason; Eracleous, M.; Gronwall, C.; Shemmer, O.; Netzer, H.; Sturm, E.; Ciardullo, R. 2011-01-01 We present a study of the morphology and intensity of star formation in the host galaxies of eight Palomar-Green quasars using observations with the Hubble Space Telescope. Accretion-powered and star formation activity have been shown to coincide, motivating us to search for the star-forming regions in the host galaxies of quasars and to determine the star-formation rates. In this work we use calibrated narrow band emission line (H-beta and Pa-alpha) WFPC2 and NICMOS images as maps for total star formation rate. The main challenge in imaging quasar host galaxies is the separation of the quasar light from the galaxy light, especially in the case of z approximately 0.1 quasars in WFPC2 images where the PSF radius closely matches the expected host scale radius. To this this end we present a novel technique for image decomposition and subtraction of quasar light, which we have validated through extensive simulations using artificial quasar+galaxy images. The other significant challenge in mapping and measuring star forming regions is correcting for extinction, which we address using extinction maps created from the Pa-alpha/H-beta ratio. To determine the source of excitation, we utilize H-beta along with [OIII]5007 and [OII]3727 images in diagnostic line ratio (BPT) diagrams. We detect extended line emission in our targets on scales of order 1-2 kpc. A preliminary analysis suggests star formation rates of order 10 solar masses per year. 1. zCOSMOS-10k-bright spectroscopic sample. The bimodality in the galaxy stellar mass function : Exploring its evolution with redshift Pozzetti, L.; Bolzonella, M.; Zucca, E.; Zamorani, G.; Lilly, S.; Renzini, A.; Moresco, M.; Mignoli, M.; Cassata, P.; Tasca, L.; Lamareille, F.; Maier, C.; Meneux, B.; Halliday, C.; Oesch, P.; Vergani, D.; Caputi, K.; Kovac, K.; Cimatti, A.; Cucciati, O.; Iovino, A.; Peng, Y.; Carollo, M.; Contini, T.; P. Kneib, J.; Le F'evre, O.; Mainieri, V.; Scodeggio, M.; Bardelli, S.; Bongiorno, A.; Coppa, G.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Kampczyk, P.; Knobel, C.; F. Le Borgne, J.; Le Brun, V.; Pello, R.; Perez Montero, E.; Ricciardelli, E.; D. Silverman, J.; Tanaka, M.; Tresse, L.; Abbas, U.; Bottini, D.; Cappi, A.; Guzzo, L.; M. Koekemoer, A.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; J. McCracken, H.; Memeo, P.; Porciani, C.; Scaramella, R.; Scarlata, C.; Scoville, N. 2010-01-01 We present the galaxy stellar mass function (GSMF) to redshift z similar or equal to 1, based on the analysis of about 8500 galaxies with I <22.5 (AB mag) over 1.4 deg(2), which are part of the zCOSMOS-bright 10k spectroscopic sample. We investigate the total GSMF, as well as the contributions of ea 2. zCOSMOS-10k-bright spectroscopic sample. The bimodality in the galaxy stellar mass function : Exploring its evolution with redshift Pozzetti, L.; Bolzonella, M.; Zucca, E.; Zamorani, G.; Lilly, S.; Renzini, A.; Moresco, M.; Mignoli, M.; Cassata, P.; Tasca, L.; Lamareille, F.; Maier, C.; Meneux, B.; Halliday, C.; Oesch, P.; Vergani, D.; Caputi, K.; Kovac, K.; Cimatti, A.; Cucciati, O.; Iovino, A.; Peng, Y.; Carollo, M.; Contini, T.; P. Kneib, J.; Le F'evre, O.; Mainieri, V.; Scodeggio, M.; Bardelli, S.; Bongiorno, A.; Coppa, G.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Kampczyk, P.; Knobel, C.; F. Le Borgne, J.; Le Brun, V.; Pello, R.; Perez Montero, E.; Ricciardelli, E.; D. Silverman, J.; Tanaka, M.; Tresse, L.; Abbas, U.; Bottini, D.; Cappi, A.; Guzzo, L.; M. Koekemoer, A.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; J. McCracken, H.; Memeo, P.; Porciani, C.; Scaramella, R.; Scarlata, C.; Scoville, N. 2010-01-01 We present the galaxy stellar mass function (GSMF) to redshift z similar or equal to 1, based on the analysis of about 8500 galaxies with I <22.5 (AB mag) over 1.4 deg(2), which are part of the zCOSMOS-bright 10k spectroscopic sample. We investigate the total GSMF, as well as the contributions of ea 3. Extreme emission-line galaxies out to z similar to 1 in zCOSMOS I. Sample and characterization of global properties Amorin, R.; Perez-Montero, F.; Contini, T.; Vilchez, J. M.; Bolzonella, M.; Tasca, L. A. M.; Lamareille, F.; Zamorani, G.; Maier, C.; Carollo, C. M.; Kneib, J. -P.; Le Fevre, O.; Lilly, S.; Mainieri, V.; Renzinis, A.; Scodeggio, M.; Bardelli, S.; Bongiorno, A.; Caputi, K.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Knobel, C.; Kovac, K.; Le Borgne, J. -F.; Le Brun, V.; Mignoli, M.; Pello, R.; Peng, Y.; Presotto, V.; Ricciardelli, E.; Silverman, J. D.; Tanaka, M.; Tresse, L.; Vergani, D.; Zucca, E. 2015-01-01 Context. The study of large and representative samples of low-metallicity star-forming galaxies at different cosmic epochs is of great interest to the detailed understanding of the assembly history and evolution of low-mass galaxies. Aims. We present a thorough characterization of a large sample of 4. The zCOSMOS survey : the role of the environment in the evolution of the luminosity function of different galaxy types Zucca, E.; Bardelli, S.; Bolzonella, M.; Zamorani, G.; Ilbert, O.; Pozzetti, L.; Mignoli, M.; Kovac, K.; Lilly, S.; Tresse, L.; Tasca, L.; Cassata, P.; Halliday, C.; Vergani, D.; Caputi, K.; Carollo, C. M.; Contini, T.; Kneib, J-P.; Le Fevre, O.; Mainieri, V.; Renzini, A.; Scodeggio, M.; Bongiorno, A.; Coppa, G.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Knobel, C.; Lamareille, F.; Le Borgne, J-F.; Le Brun, V.; Maier, C.; Pello, R.; Peng, Y.; Perez-Montero, E.; Ricciardelli, E.; Silverman, J. D.; Tanaka, M.; Abbas, U.; Bottini, D.; Cappi, A.; Cimatti, A.; Guzzo, L.; Koekemoer, A. M.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Meneux, B.; Moresco, M.; Oesch, P.; Porciani, C.; Scaramella, R.; Arnouts, S.; Aussel, H.; Capak, P.; Kartaltepe, J.; Salvato, M.; Sanders, D.; Scoville, N.; Taniguchi, Y.; Thompson, D. 2009-01-01 Aims. An unbiased and detailed characterization of the galaxy luminosity function (LF) is a basic requirement in many astrophysical issues: it is of particular interest in assessing the role of the environment in the evolution of the LF of different galaxy types. Methods. We studied the evolution in 5. AGN Absorption Linked to Host Galaxies Juneau, Stéphanie 2013-01-01 Multiwavelength identification of AGN is crucial not only to obtain a more complete census, but also to learn about the physical state of the nuclear activity (obscuration, efficiency, etc.). A panchromatic strategy plays an especially important role when the host galaxies are star-forming. Selecting far-Infrared galaxies at 0.3host galaxies, indicating a physical link between X-ray absorption and either the gas fraction or the gas geometry in the hosts. These findings have implications for our current understanding of both the AGN unification model and the nature of the black hole-galaxy connection. These proceedi... 6. Clustering of supernova Ia host galaxies Carlberg, R G; Le Borgne, D; Conley, A; Howell, D A; Perrett, K; Astier, Pierre; Balam, D; Balland, C; Basa, S; Hardin, D; Fouchez, D; Guy, J; Hook, I; Pain, R; Pritchet, C J; Regnault, N; Rich, J; Perlmutter, S 2008-01-01 For the first time the cross-correlation between type Ia supernova host galaxies and surrounding field galaxies is measured using the Supernova Legacy Survey sample. Over the z=0.2 to 0.9 redshift range we find that supernova hosts are correlated an average of 60% more strongly than similarly selected field galaxies over the 3-100 arcsec range and about a factor of 3 more strongly below 10 arcsec. The correlation errors are empirically established with a jackknife analysis of the four SNLS fields. The hosts are more correlated than the field at a significance of 99% in the fitted amplitude and slope, with the point-by-point difference of the two correlation functions having a reduced \\chi^2 for 8 degrees of freedom of 4.3, which has a probability of random occurrence of less than 3x10^{-5}. The correlation angle is 1.5+/-0.5 arcsec, which deprojects to a fixed co-moving correlation length of approximately 6.5+/- 2/h mpc. Weighting the field galaxies with the mass and star formation rate supernova frequencie... 7. zCOSMOS - 10k-bright spectroscopic sample. The bimodality in the Galaxy Stellar Mass Function: exploring its evolution with redshift Pozzetti, L; Zucca, E; Zamorani, G; Lilly, S; Renzini, A; Moresco, M; Mignoli, M; Cassata, P; Tasca, L; Lamareille, E; Maier, C; Meneux, B; Oesch, P; Vergani, D; Caputi, K; Kovac, K; Cimatti, A; Cucciati, O; Iovino, A; Peng, Y; Carollo, M; Contini, T; Kneib, J P; Le Fèvre, O; Mainieri, V; Scodeggio, M; Bardelli, S; Bongiorno, A; Coppa, G; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Kampczyk, P; Knobel, C; Le Borgne, J F; Le Brun, V; Pellò, R; Montero, E Perez; Ricciardelli, E; Silverman, Joseph; Tanaka, M; Tresse, L; Abbas, U; Bottini, D; Cappi, A; Guzzo, L; Halliday, C; Leauthaud, A; Koekemoer, A; MacCagni, D; Marinoni, C; McCracken, H; Memeo, P; Porciani, C; Scaramella, R; Scarlata, C; Scoville, N 2009-01-01 We present the Galaxy Stellar Mass Function (GSMF) up to z~1 from the zCOSMOS-bright 10k spectroscopic sample. We investigate the total MF and the contribution of ETGs and LTGs, defined by broad-band SED, morphology, spectral properties or star formation activities. We unveil a galaxy bimodality in the global MF, at least up to the z~0.55, better represented by 2 Schechter functions dominated by ETGs and LTGs, respectively. For the global population we confirm that low-mass galaxies number density increases later and faster than for massive galaxies. We find that the MF evolution at intermediate-low Mstar (logM<10.6) is mostly explained by a growth in stellar mass driven by smooth and decreasing SFHs. The low/negligible evolution at higher Mstar sets a limit of 30-15%, decreasing with redshift, to the fraction of major merging. We find that ETGs increase in number density with cosmic time faster for decreasing Mstar, with a median "building redshift" increasing with mass, in contrast with hierarchical mode... 8. The zCOSMOS survey : The dependence of clustering on luminosity and stellar mass at z=0.2-1 Meneux, B.; Guzzo, L.; de la Torre, S.; Porciani, C.; Zamorani, G.; Abbas, U.; Bolzonella, M.; Garilli, B.; Iovino, A.; Pozzetti, L.; Zucca, E.; Lilly, S. J.; Le Fevre, O.; Kneib, J. -P.; Carollo, C. M.; Contini, T.; Mainieri, V.; Renzini, A.; Scodeggio, M.; Bardelli, S.; Bongiorno, A.; Caputi, K.; Coppa, G.; Cucciati, O.; de Ravel, L.; Franzetti, P.; Kampczyk, P.; Knobel, C.; Kovac, K.; Lamareille, F.; Le Borgne, J. -F.; Le Brun, V.; Maier, C.; Pello, R.; Peng, Y.; Montero, E. Perez; Ricciardelli, E.; Silverman, J. D.; Tanaka, M.; Tasca, L.; Tresse, L.; Vergani, D.; Bottini, D.; Cappi, A.; Cimatti, A.; Cassata, P.; Fumana, M.; Koekemoer, A. M.; Leauthaud, A.; Maccagni, D.; Marinoni, C.; McCracken, H. J.; Memeo, P.; Oesch, P.; Scaramella, R. 2009-01-01 Aims. We study the dependence of galaxy clustering on luminosity and stellar mass at redshifts z similar to [0.2-1], using the first 10K redshifts from the zCOSMOS spectroscopic survey of the COSMOS field. Methods. We measured the redshift-space correlation functions xi(r(p), pi) and xi(s) and the p 9. A Fast Radio Burst Host Galaxy Keane, E F; Bhandari, S; Barr, E; Bhat, N D R; Burgay, M; Caleb, M; Flynn, C; Jameson, A; Kramer, M; Petroff, E; Possenti, A; van Straten, W; Bailes, M; Burke-Spolaor, S; Eatough, R P; Stappers, B W; Totani, T; Honma, M; Furusawa, H; Hattori, T; Morokuma, T; Niino, Y; Sugai, H; Terai, T; Tominaga, N; Yamasaki, S; Yasuda, N; Allen, R; Cooke, J; Jencson, J; Kasliwal, M M; Kaplan, D L; Tingay, S J; Williams, A; Wayth, R; Chandra, P; Perrodin, D; Berezina, M; Mickaliger, M; Bassa, C 2016-01-01 In recent years, millisecond duration radio signals originating from distant galaxies appear to have been discovered in the so-called Fast Radio Bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity which, in tandem with a redshift measurement, can be used for fundamental physical investigations. While every fast radio burst has a dispersion measurement, none before now have had a redshift measurement, due to the difficulty in pinpointing their celestial coordinates. Here we present the discovery of a fast radio burst and the identification of a fading radio transient lasting \\sim 6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z=0.492\\pm0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionised baryons in the intergalactic medium of \\Omega_{\\mathrm{IGM}}=4.9 \\pm 1.3\\%, in agreement with the expectation from WMAP, and i... 10. Radio Galaxy Zoo: host galaxies and radio morphologies derived from visual inspection Banfield, J. K.; Wong, O. I.; Willett, K. W.; Norris, R. P.; Rudnick, L.; Shabala, S. S.; Simmons, B. D.; Snyder, C.; Garon, A.; Seymour, N.; Middelberg, E.; Andernach, H.; Lintott, C. J.; Jacob, K.; Kapińska, A. D.; Mao, M. Y.; Masters, K. L.; Jarvis, M. J.; Schawinski, K.; Paget, E.; Simpson, R.; Klöckner, H.-R.; Bamford, S.; Burchell, T.; Chow, K. E.; Cotter, G.; Fortson, L.; Heywood, I.; Jones, T. W.; Kaviraj, S.; López-Sánchez, Á. R.; Maksym, W. P.; Polsterer, K.; Borden, K.; Hollow, R. P.; Whyte, L. 2015-11-01 We present results from the first 12 months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170 000 radio sources to determine the host galaxy of the radio emission and the radio morphology. Radio Galaxy Zoo uses 1.4 GHz radio images from both the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) and the Australia Telescope Large Area Survey (ATLAS) in combination with mid-infrared images at 3.4 μm from the Wide-field Infrared Survey Explorer (WISE) and at 3.6 μm from the Spitzer Space Telescope. We present the early analysis of the WISE mid-infrared colours of the host galaxies. For images in which there is >75 per cent consensus among the Radio Galaxy Zoo cross-identifications, the project participants are as effective as the science experts at identifying the host galaxies. The majority of the identified host galaxies reside in the mid-infrared colour space dominated by elliptical galaxies, quasi-stellar objects and luminous infrared radio galaxies. We also find a distinct population of Radio Galaxy Zoo host galaxies residing in a redder mid-infrared colour space consisting of star-forming galaxies and/or dust-enhanced non-star-forming galaxies consistent with a scenario of merger-driven active galactic nuclei (AGN) formation. The completion of the full Radio Galaxy Zoo project will measure the relative populations of these hosts as a function of radio morphology and power while providing an avenue for the identification of rare and extreme radio structures. Currently, we are investigating candidates for radio galaxies with extreme morphologies, such as giant radio galaxies, late-type host galaxies with extended radio emission and hybrid morphology radio sources. 11. Galaxy Zoo: evidence for rapid, recent quenching within a population of AGN host galaxies Smethurst, R. J.; Lintott, C. J.; Simmons, B. D.; Schawinski, K.; Bamford, S. P.; Cardamone, C. N.; Kruk, S. J.; Masters, K. L.; Urry, C. M.; Willett, K. W.; Wong, O. I. 2016-12-01 We present a population study of the star formation history of 1244 Type 2 active galactic nuclei (AGN) host galaxies, compared to 6107 inactive galaxies. A Bayesian method is used to determine individual galaxy star formation histories, which are then collated to visualize the distribution for quenching and quenched galaxies within each population. We find evidence for some of the Type 2 AGN host galaxies having undergone a rapid drop in their star formation rate within the last 2 Gyr. AGN feedback is therefore important at least for this population of galaxies. This result is not seen for the quenching and quenched inactive galaxies whose star formation histories are dominated by the effects of downsizing at earlier epochs, a secondary effect for the AGN host galaxies. We show that histories of rapid quenching cannot account fully for the quenching of all the star formation in a galaxy's lifetime across the population of quenched AGN host galaxies, and that histories of slower quenching, attributed to secular (non-violent) evolution, are also key in their evolution. This is in agreement with recent results showing that both merger-driven and non-merger processes are contributing to the co-evolution of galaxies and supermassive black holes. The availability of gas in the reservoirs of a galaxy, and its ability to be replenished, appear to be the key drivers behind this co-evolution. 12. An HST study of three very faint GRB host galaxies Jaunsen, A.O.; Andersen, M.I.; Hjorth, J.; 2003-01-01 . (2002). We obtain a revised and much higher probability that the galaxies identified as hosts indeed are related to the GRBs (P(n(chance))=0.69, following Bloom et al. 2002), thereby strengthening the conclusion that GRBs are preferentially located in star-forming regions in their hosts. Apart from......As part of the HST/STIS GRB host survey program we present the detection of three faint gamma-ray burst (GRB) host galaxies based on an accurate localisation using ground-based data of the optical afterglows (OAs). A common property of these three hosts is their extreme faintness. The location...... at which GRBs occur with respect to their host galaxies and surrounding environments are robust indicators of the nature of GRB progenitors. The bursts studied here are among the four most extreme outliers, in terms of relative distance from the host center, in the recent comprehensive study of Bloom et al... 13. Statistical Properties of Gamma-Ray Burst Host Galaxies Jie-Min Chen; Jin Zhang; Lan-Wei Jia; En-Wei Liang 2014-09-01 A statistical analysis of gamma-ray burst host galaxies is presented and a clear metallicity-stellar mass relation is found in our sample. A trend that a more massive host galaxy tends to have a higher star-formation rate is also found. No correlation is found between V and H. GRB host galaxies at a higher redshift also tend to have a higher star formation rate, however, even in the same redshift, the star formation rate may vary for three orders of magnitude. 14. Galaxies of all Shapes Host Black Holes 2008-01-01 This artist's concept illustrates the two types of spiral galaxies that populate our universe: those with plump middles, or central bulges (upper left), and those lacking the bulge (foreground). New observations from NASA's Spitzer Space Telescope provide strong evidence that the slender, bulgeless galaxies can, like their chubbier counterparts, harbor supermassive black holes at their cores. Previously, astronomers thought that a galaxy without a bulge could not have a supermassive black hole. In this illustration, jets shooting away from the black holes are depicted as thin streams. The findings are reshaping theories of galaxy formation, suggesting that a galaxy's 'waistline' does not determine whether it will be home to a big black hole. 15. Stripped-envelope supernova rates and host-galaxy properties Graur, Or; Modjaz, Maryam; Maoz, Dan; Shivvers, Isaac; Filippenko, Alexei V; Li, Weidong 2015-01-01 The progenitors of stripped-envelope supernovae (SNe Ibc) remain to be conclsuively identified, but correlations between SN rates and host-galaxy properties can constrain progenitor models. Here, we present one result from a re-analysis of the rates from the Lick Observatory Supernova Search. Galaxies with stellar masses less than \\sim 10^{10}~{\\rm M_\\odot} are less efficient at producing SNe Ibc than more massive galaxies. Any progenitor scenario must seek to explain this new observation. 16. The host galaxies of AGN with powerful relativistic jets Olguín-Iglesias, A.; León-Tavares, J.; Kotilainen, J. K.; Chavushyan, V.; Tornikoski, M.; Valtaoja, E.; Añorve, C.; Valdés, J.; Carrasco, L. 2016-08-01 We present deep Near-infrared (NIR) images of a sample of 19 intermediate-redshift (0.310^27 WHz^-1), previously classified as flat-spectrum radio quasars. We also compile host galaxy and nuclear magnitudes for blazars from literature. The combined sample (this work and compilation) contains 100 radio-loud AGN with host galaxy detections and a broad range of radio luminosities L1.4GHz = 10^23.7 - 10^28.3WHz^-1, allowing us to divide our sample into high-excitation (quasar-mode; HERGs) and low-excitation (radio-mode; LERGs) radio galaxies. The host galaxies of our sample are bright and seem to follow the Kormendy relation. Nuclear emission (dominated by non-thermal mechanisms) and host-galaxy magnitudes show a slightly negative weak trend for LERGs. On the other hand, the m_bulge -m_nuc relation is statistically significant for HERGs. Although it may be affected by selection effects, this correlation suggests a close coupling between the relativistic jets and their host galaxy. Our findings are consistent with the excitation state (LERG/HERG) scenario. In this view, LERGs emit the bulk of their energy in the form of radio jets, producing a strong feedback mechanism, and HERGs are affected by galaxy mergers and interactions, which provide a common supply of cold gas to feed both nuclear activity and star formation episodes. 17. Galaxy Zoo: Evidence for rapid, recent quenching within a population of AGN host galaxies Smethurst, R J; Simmons, B D; Schawinski, K; Bamford, S P; Cardamone, C N; Kruk, S J; Masters, K L; Urry, C M; Willett, K W; Wong, O I 2016-01-01 We present a population study of the star formation history of 1244 Type 2 AGN host galaxies, compared to 6107 inactive galaxies. A Bayesian method is used to determine individual galaxy star formation histories, which are then collated to visualise the distribution for quenching and quenched galaxies within each population. We find evidence for some of the Type 2 AGN host galaxies having undergone a rapid drop in their star formation rate within the last 2 Gyr. AGN feedback is therefore important at least for this population of galaxies. This result is not seen for the quenching and quenched inactive galaxies whose star formation histories are dominated by the effects of downsizing at earlier epochs, a secondary effect for the AGN host galaxies. We show that histories of rapid quenching cannot account fully for the quenching of all the star formation in a galaxy's lifetime across the population of quenched AGN host galaxies, and that histories of slower quenching, attributed to secular (non-violent) evolutio... 18. Black Hole Mass, Host galaxy classification and AGN activity McKernan, Barry; Reynolds, Chris 2010-01-01 We investigate the role of host galaxy classification and black hole mass in a heterogeneous sample of 276 mostly nearby (z99% confidence. Using ring morphology of the host galaxy as a proxy for lack of tidal interaction, we find that AGN luminosity in host galaxies within 70Mpc is independent of host galaxy interaction for \\sim Gyrs, suggesting that the timescale of AGN activity due to secular evolution is much shorter than that due to tidal interactions. We find that LINER hosts have lower 12um luminosity than the median 12um luminosity of normal disk- and bulge-dominated galaxies which may represent observational evidence for past epochs of feedback that supressed star formation in LINER host galaxies. We propose that nuclear ULXs may account for the X-ray emission from LI NER 2s without flat-spectrum, compact radio cores. We confirmed the robustness of our results in X-rays by comparing them with the 14-195keV 22-month BAT survey of AGN, which is all-sky and unbiased by photoelectric absorption. 19. Gas Kinematics in GRB Host Galaxies Arabsalmani, Maryam The star formation history of the Universe is one of the most complex and interesting chapters in our quest to understand galaxy formation and evolution. Gamma Ray Bursts (GRBs) are beacons of actively star forming galaxies from redshifts near zero back to the cosmic dawn. In addition, they provide... 20. Gas Kinematics in GRB Host Galaxies Arabsalmani, Maryam The star formation history of the Universe is one of the most complex and interesting chapters in our quest to understand galaxy formation and evolution. Gamma Ray Bursts (GRBs) are beacons of actively star forming galaxies from redshifts near zero back to the cosmic dawn. In addition, they provide... 1. HOST GALAXIES OF X-SHAPED RADIO SOURCES Springmann, A.; Cheung, C. 2007-01-01 Most radiation from galaxies containing active galactic nuclei (AGNs) is emitted not by the stars composing the galaxy, but from an active source at the galactic center, most likely a supermassive black hole. Of particular interest are radio galaxies, active galaxies that emit much of their radiation at radio wavelengths. Within each radio galaxy, an AGN powers a pair of collimated jets of relativistic particles, forming a pair of giant lobes at the end of the jets and thus giving a characteristic double-lobed appearance. A particular class of radio galaxies has an “X”-or winged-shaped morphology: in these, two pairs of lobes appear to originate from the galactic center, producing a distinctive X-shape. Two main mechanisms have been proposed to explain the X-shape morphology: one being a realignment of the black hole within the AGN and the second positing that the radio jets are expanding into an asymmetric medium, causing backflow and producing secondary wings. By analyzing radio host galaxy shapes, the distribution of the stellar mass is compared to the differing model expectations regarding the distribution of the surrounding gas and stellar material about the AGN. Results show elliptical host galaxies with an orthogonal offset between the semi-major axis of the host galaxy and the secondary radio wings, which lends support to the hydrodynamical model. However, results also show circular host galaxies with radio wings, making the realignment scenario a more likely model to describe the formation of these X-shaped radio sources. 2. The zCOSMOS Redshift Survey: the role of environment and stellar mass in shaping the rise of the morphology-density relation from z~1 Tasca, L A M; Iovino, A; Le Fèvre, O; Kovac, K; Bolzonella, M; Lilly, S J; Abraham, R G; Cassata, P; Cucciati, O; Guzzo, L; Tresse, L; Zamorani, G; Capak, P; Garilli, B; Scodeggio, M; Sheth, K; Vergani, D; Zucca, E; Carollo, C M; Contini, T; Mainieri, V; Renzini, A; Bardelli, S; Bongiorno, A; Caputi, K; Coppa, G; De la Torre, S; de Ravel, L; Franzetti, P; Kampczyk, P; Knobel, C; Koekemoer, A; Lamareille, F; Le Borgne, J F; Le Brun, V; Maier, C; Mignoli, M; Pellò, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Silverman, J D; Tanaka, M; Abbas, U; Bottini, D; Cappi, A; Cimatti, A; Ilbert, O; Leauthaud, A; MacCagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Pozzetti, L; Scaramella, R; Scarlata, C 2009-01-01 For more than two decades we have known that galaxy morphological segregation is present in the Local Universe. It is important to see how this relation evolves with cosmic time. To investigate how galaxy assembly took place with cosmic time, we explore the evolution of the morphology-density relation up to redshift z~1 using about 10000 galaxies drawn from the zCOSMOS Galaxy Redshift Survey. Taking advantage of accurate HST/ACS morphologies from the COSMOS survey, of the well-characterised zCOSMOS 3D environment, and of a large sample of galaxies with spectroscopic redshift, we want to study here the evolution of the morphology-density relation up to z~1 and its dependence on galaxy luminosity and stellar mass. The multi-wavelength coverage of the field also allows a first study of the galaxy morphological segregation dependence on colour. We further attempt to disentangle between processes that occurred early in the history of the Universe or late in the life of galaxies. The zCOSMOS field benefits of high-... 3. Radio Afterglows and Host Galaxies of Gamma-Ray Bursts Li, Long-Biao; Huang, Yong-Feng; Wu, Xue-Feng; Kong, Si-Wei; Li, Di; Chang, Heon-Young; Choi, Chul-Sung 2015-01-01 Considering the contribution of the emission from the host galaxies of gamma-ray bursts (GRBs) to the radio afterglows, we investigate the effect of host galaxies on observations statistically. For the three types of events, e.g. low-luminosity, standard and high-luminosity GRBs, it is found that a tight correlation exists between the ratio of the radio flux (RRF) of host galaxy to the total radio peak emission and the observational frequency. Especially, toward lower frequencies, the contribution from the host increases significantly. The correlation can be used to get a useful estimate for the radio brightness of those host galaxies which only have very limited radio afterglow data. Using this prediction, we re-considered the theoretical radio afterglow light curves for four kinds of events, i.e. high-luminosity, low-luminosity, standard and failed GRBs, taking into account the contribution from the host galaxies and aiming at exploring the detectability of these events by the Five-hundred-meter Aperture Sp... 4. Host Galaxy Morphology and the AGN Unified Model Trump, Jonathan R 2011-01-01 We use a sample of active galaxies from the Cosmic Evolution Survey to show that host galaxy morphology is tied to the accretion rate and X-ray obscuration of its active galactic nucleus (AGN). Unobscured and rapidly accreting broad-line AGNs are more likely to be in spheroid-dominated hosts than weak or obscured AGNs, and obscured AGNs are more likely to have disturbed host galaxies. Much of the disagreement in previous work on the AGN-merger connection is likely due to each study probing AGNs with different obscuration and accretion properties. Only obscured AGNs seem to merger-driven, while weak AGNs are fed by stochastic processes in disks, and rapidly-accreting broad-line AGNs require massive bulges. Our observed "unified model" for AGN hosts fits with theoretical models for merger-driven AGN evolution, but is also consistent with steady-state AGN activity. 5. Radio Galaxy Zoo: host galaxies and radio morphologies derived from visual inspection Banfield, J K; Willett, K W; Norris, R P; Rudnick, L; Shabala, S S; Simmons, B D; Snyder, C; Garon, A; Seymour, N; Middelberg, E; Andernach, H; Lintott, C J; Jacob, K; Kapinska, A D; Mao, M Y; Masters, K L; Jarvis, M J; Schawinski, K; Paget, E; Simpson, R; Klockner, H R; Bamford, S; Burchell, T; Chow, K E; Cotter, G; Fortson, L; Heywood, I; Jones, T W; Kaviraj, S; Lopez-Sanchez, A R; Maksym, W P; Polsterer, K; Borden, K; Hollow, R P; Whyte, L 2015-01-01 We present results from the first twelve months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170,000 radio sources to determine the host galaxy of the radio emission and the radio morphology. Radio Galaxy Zoo uses 1.4\\,GHz radio images from both the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) and the Australia Telescope Large Area Survey (ATLAS) in combination with mid-infrared images at 3.4\\,\\mum from the {\\it Wide-field Infrared Survey Explorer} (WISE) and at 3.6\\,\\mum from the {\\it Spitzer Space Telescope}. We present the early analysis of the WISE mid-infrared colours of the host galaxies. For images in which there is >\\,75\\% consensus among the Radio Galaxy Zoo cross-identifications, the project participants are as effective as the science experts at identifying the host galaxies. The majority of the identified host galaxies reside in the mid-infrared colour space dominated by elliptical galaxies, quasi-stellar objects (QSOs), and l... 6. How SN Ia host-galaxy properties affect cosmological parameters Campbell, H; Gilmore, G 2016-01-01 We present a systematic study of the relationship between Type Ia Supernova (SN Ia) properties, and the characteristics of their host galaxies, using a sample of 581 SNe Ia from the full Sloan Digital Sky Survey II (SDSS-II) SN Survey. We also investigate the effects of this on the cosmological constraints derived from SNe~Ia. Compared to previous studies, our sample is larger by a factor of >4, and covers a substantially larger redshift range (up to z~0.5), which is directly applicable to the volume of cosmological interest. We measure a significant correlation (>5\\sigma) between the host-galaxy stellar-mass and the SN~Ia Hubble Residuals (HR). We find a weak correlation (1.4\\sigma) between the host-galaxy metallicity as measured from emission lines in the spectra, and the SN~Ia HR. We also find evidence that the slope of the correlation between host-galaxy mass and HR is -0.11 \\mathrm{mag}/\\mathrm{log}(\\mathrm{M}_{\\mathrm{host}}/\\mathrm{M}_{\\odot}) steeper in lower metallicity galaxies. We test the effe... 7. The nuclear to host galaxy relation of high redshift quasars Kotilainen, J K; Labita, M; Treves, A; Uslenghi, M 2007-01-01 We present near-infrared imaging with ESO VLT+ISAAC of the host galaxies of low luminosity quasars in the redshift range 1 < z < 2, aimed at investigating the relationship between the nuclear and host galaxy luminosities at high redshift. This work complements our previous study to trace the cosmological evolution of the host galaxies of high luminosity quasars (Falomo et al. 2004). The new sample includes 15 low luminosity quasars, nine radio-loud (RLQ) and six radio-quiet (RQQ). They have similar distribution of redshift and optical luminosity, and together with the high luminosity quasars they cover a large range (~4 mag) of the quasar luminosity function. The host galaxies of both types of quasars are in the range of massive inactive ellipticals between L* and 10 L*. RLQ hosts are systematically more luminous than RQQ hosts by a factor of ~2. This difference is similar to that found for the high luminosity quasars. This luminosity gap appears to be independent of the rest-frame U-band luminosity but... 8. The Black Hole - Bulge Mass Relation in Megamaser Host Galaxies Läsker, Ronald; Seth, Anil; van de Ven, Glenn; Braatz, James A; Henkel, Christian; Lo, K Y 2016-01-01 We present HST images for nine megamaser disk galaxies with the primary goal of studying photometric BH-galaxy scaling relations. The megamaser disks provide the highest-precision extragalactic BH mass measurements, while our high-resolution HST imaging affords us the opportunity to decompose the complex nuclei of their late-type hosts in detail. Based on the morphologies and shapes of the galaxy nuclei, we argue that most of these galaxies' central regions contain secularly evolving components (pseudo-bulges), and in many cases we photometrically identify co-existing "classical" bulge components as well. Using these decompositions, we draw the following conclusions: (1) The megamaser BH masses span two orders of magnitude (10^6 -- 10^8 M_\\odot) while the stellar mass of their spiral host galaxies are all \\sim 10^{11} M_\\odot within a factor of three; (2) the BH masses at a given bulge mass or total stellar mass in the megamaser host spiral galaxies tend to be lower than expected, when compared to an ex... 9. The Dependence of Galaxy Type on Host Halo Mass Weinmann, S M; Yang, X; Mo, H J; Weinmann, Simone M.; Bosch, Frank C. van den; Yang, Xiaohu 2006-01-01 We examine the relation between galaxy properties and environment in the SDSS DR2, quantifying environment in terms of the mass of the host halo, which is obtained with a new iterative group finder. We find that galaxy type fractions scale strongly and smoothly with halo mass, but, at fixed mass, not with luminosity. We compare these findings with the semi-analytical galaxy formation model of Croton et al. (2006). The discrepancies we find can be explained with an oversimplified implementation of strangulation, the neglect of tidal stripping, and shortcomings in the treatments of dust extinction and/or AGN feedback. 10. Gemini imaging of QSO host galaxies at z~2 Croom, S; Boyle, B; Shanks, T; Miller, L; Smith, R; Croom, Scott; Schade, David; Boyle, Brian; Shanks, Tom; Miller, Lance; Smith, Robert 2004-01-01 We present results of a Gemini adaptive optics (AO) imaging program to investigate the host galaxies of typical QSOs at z~2. Our aim is to study the host galaxies of typical, L*_qso QSOs at the epoch of peak QSO and star formation activity. The large database of faint QSOs provided by the 2dF QSO Redshift Survey allows us to select a sample of QSOs at z=1.75-2.5 which have nearby (<12 arcsecond separation) bright stars suitable for use as AO guide stars. We have observed a sample of 9 QSOs. The images of these sources have AO corrected full-width at half-maximum of between 0.11 and 0.25 arcseconds. We use multiple observations of point spread function (PSF) calibration star pairs in order to quantify any uncertainty in the PSF. We then factored these uncertainties into our modelling of the QSO plus host galaxy. In only one case did we convincingly detect a host (2QZ J133311.4+001949, at z=1.93). This host galaxy has K=18.5+-0.2 mag with a half-light radius, r_e=0.55+-0.1'', equivalent to ~3L*_gal assuming ... 11. The extremely red host galaxy of GRB 080207 Hunt, Leslie; Rossi, Andrea; Savaglio, Sandra; Cresci, Giovanni; Klose, Sylvio; Michalowski, Michal; Pian, Elena 2011-01-01 We present optical, near-infrared, and Spitzer IRAC and MIPS observations of the host galaxy of the dark gamma-ray burst GRB 080207. The host is faint, with extremely red optical-infrared colors (R-K\\,=\\,6.3, 24\\micron/R-band flux \\sim1000) making it an extremely red object (ERO) and a dust-obscured galaxy (DOG). The spectral energy distribution (SED) shows the clear signature of the 1.6 micron photometric "bump", typical of evolved stellar populations. We use this bump to establish the photometric redshift z_{\\rm phot} as 2.2^{+0.2}_{-0.3}, using a vast library of SED templates, including M 82. The star-formation rate (SFR) inferred from the SED fitting is \\sim119\\msun\\,yr^{-1}, the stellar mass 3\\times10^{11}\\,\\msun, and \\av\\ extinction from 1-2\\,mag. The ERO and DOG nature of the host galaxy of the dark GRB 080207 may be emblematic of a distinct class of dark GRB hosts, with high SFRs, evolved and metal-rich stellar populations, and significant dust extinction within the host galaxy. 12. The Fate of Young Radio Galaxies: Decelerations Inside Host Galaxies? Kawakatu, Nozomu; Kino, Motoki 2008-01-01 We examine the evolution of variously-sized radio galaxies [i.e., compact symmetric objects (CSOs), medium-size symmetric objects (MSOs), Fanaroff-Riley type II radio galaxies (FRIIs)], by comparing the relation between the hot spot size and the projected linear size with a coevolution model of hot spots and a cocoon. We take account of the deceleration effect by the cocoon head growth. We find that the advance speed of hot spots and lobes inevitably show the deceleration phase (CSO-MSO phase) and the acceleration phase (MSO-FRII phase). This is ascribed to the change of the power-law index of ambient density profile in the MSO phase (\\sim 1 kpc). It is also found that the cocoon shape becomes nearly spherical or disrupted for MSOs, while an elongated morphology is predicted for CSOs and FRIIs. This seems to be consistent with the higher fraction of distorted morphology of MSOs than that of CSOs and FRI. Finally, we predict that only CSOs whose initial advance speed is higher than about 0.1c can evolve into... 13. Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies Kormendy, John; Ho, Luis C. 2013-08-01 Supermassive black holes (BHs) have been found in 85 galaxies by dynamical modeling of spatially resolved kinematics. The Hubble Space Telescope revolutionized BH research by advancing the subject from its proof-of-concept phase into quantitative studies of BH demographics. Most influential was the discovery of a tight correlation between BH mass [Formula: see text] and the velocity dispersion σ of the bulge component of the host galaxy. Together with similar correlations with bulge luminosity and mass, this led to the widespread belief that BHs and bulges coevolve by regulating each other's growth. Conclusions based on one set of correlations from [Formula: see text] in brightest cluster ellipticals to [Formula: see text] in the smallest galaxies dominated BH work for more than a decade. New results are now replacing this simple story with a richer and more plausible picture in which BHs correlate differently with different galaxy components. A reasonable aim is to use this progress to refine our understanding of BH-galaxy coevolution. BHs with masses of 105-106M⊙ are found in many bulgeless galaxies. Therefore, classical (elliptical-galaxy-like) bulges are not necessary for BH formation. On the other hand, although they live in galaxy disks, BHs do not correlate with galaxy disks. Also, any [Formula: see text] correlations with the properties of disk-grown pseudobulges and dark matter halos are weak enough to imply no close coevolution. The above and other correlations of host-galaxy parameters with each other and with [Formula: see text] suggest that there are four regimes of BH feedback. (1) Local, secular, episodic, and stochastic feeding of small BHs in largely bulgeless galaxies involves too little energy to result in coevolution. (2) Global feeding in major, wet galaxy mergers rapidly grows giant BHs in short-duration, quasar-like events whose energy feedback does affect galaxy evolution. The resulting hosts are classical bulges and coreless 14. Simple stellar population modelling of low S/N galaxy spectra and quasar host galaxy applications Mosby, G.; Tremonti, C. A.; Hooper, E. J.; Wolf, M. J.; Sheinis, A. I.; Richards, J. W. 2015-02-01 To study the effect of supermassive black holes (SMBHs) on their host galaxies it is important to study the hosts when the SMBH is near its peak activity. A method to investigate the host galaxies of high luminosity quasars is to obtain optical spectra at positions offset from the nucleus where the relative contribution of the quasar and host is comparable. However, at these extended radii the galaxy surface brightness is often low (20-22 mag arcsec-2) and the resulting spectrum might have such low signal-to-noise ratio (S/N) that it hinders analysis with standard stellar population modelling techniques. To address this problem, we have developed a method that can recover galaxy star formation histories (SFHs) from rest-frame optical spectra with S/N ˜ 5 Å-1. This method uses the statistical technique diffusion k-means to tailor the stellar population modelling basis set. Our diffusion k-means minimal basis set, composed of four broad age bins, is successful in recovering a range of galaxy SFHs. Additionally, using an analytic prescription for seeing conditions, we are able to simultaneously model scattered quasar light and the SFH of quasar host galaxies (QHGs). We use synthetic data to compare results of our novel method with previous techniques. We also present the modelling results on a previously published QHG and show that galaxy properties recovered from a diffusion k-means basis set are less sensitive to noise added to this QHG spectrum. Our new method has a clear advantage in recovering information from QHGs and could also be applied to the analysis of other low S/N galaxy spectra such as those typically obtained for high redshift objects or integral field spectroscopic surveys. 15. The optical afterglow and host galaxy of GRB 000926 Fynbo, J.U.; Gorosabel, J.; Dall, T.H.; 2002-01-01 In this paper we illustrate with the case of GRB 000926 how Gamma Ray Bursts (GRBs) can be used as cosmological lighthouses to identify and study star forming galaxies at high redshifts. The optical afterglow of the burst was located with optical imaging at the Nordic Optical Telescope 20.7 hours...... after the burst. Rapid follow-up spectroscopy allowed the determination of the redshift of the burst and a measurement of the host galaxy HI-column density in front of the burst. With late-time narrow band Lyalpha as well as broad band imaging, we have studied the emission from the host galaxy and found...... that it is a strong Lyalpha emitter in a state of active star formation.... 16. The blue host galaxy of the red GRB 000418 Gorosabel, J.; Klose, S.; Christensen, L. 2003-01-01 (A(V) = 0.4-0.9 mag), suggesting a homogeneous distribution of the interstellar medium (ISM) in the host galaxy. These findings are supplemented by morphological information from Hubble Space Telescope (HST) imaging: the surface brightness profile is smooth, symmetric and compact with no underlying... 17. The host of GRB 060206: kinematics of a distant galaxy Thoene, Christina C; Ledoux, Cedric; Starling, Rhaana L C; Fynbo, Johan P U; Curran, Peter A; Gorosabel, Javier; van der Horst, Alexander J; Kewley, Lisa J; Levan, Andrew J; LLorente, Alvaro; Rol, Evert; Tanvir, Nial R; Postigo, Antonio de Ugarte; Vreeswijk, Paul M; Wijers, Ralph A M J 2007-01-01 Context. The spectra of afterglows can provide us with detailed information on the line-of-sight towards high redshift gamma-ray bursts (GRBs). This allows us to use GRB afterglows as sensitive probes of interstellar matter in their host galaxies, and the circumstellar material around the progenitor star. Aims. In this paper we present early WHT/ISIS optical spectroscopy of the afterglow of the gamma-ray burst GRB 060206 at z = 4.048, detecting a range of metal absorption lines and their fine-structure transitions. Additional information is provided by properties derived from the afterglow lightcurve and from deep imaging of the host galaxy. Methods. The resolution and wavelength range of the spectra and the bright afterglow facilitate a detailed study of the circumburst and host galaxy environment through fitting of the absorption line systems. Their column densities allow us to derive properties for the different detected velocity components. We also use the deep imaging to detect the host galaxy and probe ... 18. EXTREME HOST GALAXY GROWTH IN POWERFUL EARLY-EPOCH RADIO GALAXIES Barthel, Peter [Kapteyn Astronomical Institute, University of Groningen (Netherlands); Haas, Martin [Astronomisches Institut, Ruhr Universitaet, Bochum (Germany); Leipski, Christian [Max-Planck-Institut fuer Astronomie, Heidelberg (Germany); Wilkes, Belinda, E-mail: [email protected] [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States) 2012-10-01 During the first half of the universe's life, a heyday of star formation must have occurred because many massive galaxies are in place after that epoch in cosmic history. Our observations with the revolutionary Herschel Space Observatory reveal vigorous optically obscured star formation in the ultra-massive hosts of many powerful high-redshift 3C quasars and radio galaxies. This symbiotic occurrence of star formation and black hole driven activity is in marked contrast to recent results dealing with Herschel observations of X-ray-selected active galaxies. Three archetypal radio galaxies at redshifts 1.132, 1.575, and 2.474 are presented here, with inferred star formation rates of hundreds of solar masses per year. A series of spectacular coeval active galactic nucleus/starburst events may have formed these ultra-massive galaxies and their massive central black holes during their relatively short lifetimes. 19. A Morphological Study of Gamma-Ray Burst Host Galaxies Wainwright, C; Penprase, B E 2005-01-01 We present a comprehensive study of the morphological properties of 42 gamma-ray burst (GRB) host galaxies imaged with the Hubble Space Telescope in the optical band. The purpose of this study is to understand the relation of GRBs to their macro-environments, and to compare the GRB-selected galaxies to other high redshift samples. We perform both qualitative and quantitative analyses by categorizing the galaxies according to their visual properties, and by examining their surface brightness profiles. We find that all of the galaxies have approximately exponential profiles, indicative of galactic disks, and have a median scale length of about 1.7 kpc. Inspection of the visual morphologies reveals a high fraction of merging and interacting systems, with \\~30% showing clear signs of interaction, and an additional ~30% exhibiting irregular and asymmetric structure which may be the result of recent mergers; these fractions are independent of redshift and galaxy luminosity. On the other hand, the three GRB host gal... 20. Massive relic galaxies challenge the co-evolution of SMBHs and their host galaxies Ferré-Mateu, Anna; Trujillo, Ignacio; Balcells, Marc; Bosch, Remco C E van den 2015-01-01 We study a sample of eight massive galaxies that are extreme outliers (3-5\\sigma) in the M_{\\bullet}-M_\\mathrm{bulge} local scaling relation. Two of these galaxies are confirmed to host extremely large super massive black holes (SMBHs), whereas the virial mass estimates for the other six are also consistent with having abnormally large SMBHs. From the analysis of their star formation histories and their structural properties we find that all these extreme outliers can be considered as relic galaxies from the early (z\\sim2) Universe: i.e. they are compact (R_{\\mathrm{e}}<$2 kpc) and have purely old stellar populations (t$\\gtrsim$10 Gyr). In order to explain the nature of such deviations from the local relations, we propose a scenario in which the hosts of these \\"uber-massive SMBHs are galaxies that have followed a different evolutionary path than the two-phase growth channel assumed for massive galaxies. Once the SMBH and the core of the galaxy are formed at z$\\sim$2, the galaxy skips the second... 1. Identifying the Host Galaxy of Gravitational Wave Signals Nuttall, Laura K 2010-01-01 One of the goals of the current LIGO-GEO-Virgo science run is to identify transient gravitational wave (GW) signals in near real time to allow follow-up electromagnetic (EM) observations. An EM counterpart could increase the confidence of the GW detection and provide insight into the nature of the source. Current GW-EM campaigns target potential host galaxies based on overlap with the GW sky error box. We propose a new statistic to identify the most likely host galaxy, ranking galaxies based on their position, distance, and luminosity. We test our statistic with Monte Carlo simulations of GWs produced by coalescing binaries of neutron stars (NS) and black holes (BH), one of the most promising sources for ground-based GW detectors. Considering signals accessible to current detectors, we find that when imaging a single galaxy, our statistic correctly identifies the true host ~20% to ~50% of the time, depending on the masses of the binary components. With five narrow-field images the probability of imaging the t... 2. Distributions of Quasar Hosts on the Galaxy Main Sequence Plane Zhang, Zhoujian; Shi, Yong; Rieke, George H.; Xia, Xiaoyang; Wang, Yikang; Sun, Bingqing; Wan, Linfeng 2016-03-01 The relation between star formation rates (SFRs) and stellar masses, i.e., the galaxy main sequence, is a useful diagnostic of galaxy evolution. We present the distributions relative to the main sequence of 55 optically selected PG and 12 near-IR-selected Two Micron All Sky Survey (2MASS) quasars at z ≤ 0.5. We estimate the quasar host stellar masses from Hubble Space Telescope or ground-based AO photometry, and the SFRs through the mid-infrared aromatic features and far-IR photometry. We find that PG quasar hosts more or less follow the main sequence defined by normal star-forming galaxies while 2MASS quasar hosts lie systematically above the main sequence. PG and 2MASS quasars with higher nuclear luminosities seem to have higher specific SFRs (sSFRs), although there is a large scatter. No trends are seen between sSFRs and SMBH masses, Eddington ratios, or even morphology types (ellipticals, spirals, and mergers). Our results could be placed in an evolutionary scenario with quasars emerging during the transition from ULIRGs/mergers to ellipticals. However, combined with results at higher redshift, they suggest that quasars can be widely triggered in normal galaxies as long as they contain abundant gas and have ongoing star formation. 3. Radio Galaxy Zoo: host galaxies and radio morphologies for large surveys from visual inspection Willett, Kyle W 2016-01-01 We present early results from Radio Galaxy Zoo, a web-based citizen science project for visual inspection and classification of images from all-sky radio surveys. The goals of the project are to classify individual radio sources (particularly galaxies with multiple lobes and/or complex morphologies) as well as matching the continuum radio emission to the host galaxy. Radio images come from the FIRST and ATLAS surveys, while matches to potential hosts are performed with infrared imaging from WISE and SWIRE. The first twelve months of classification yielded more than 1 million classifications of more than 60,000 sources. For images with at least 75% consensus by the volunteer classifiers, the accuracy is comparable to visual inspection by the expert science team. Based on mid-infrared colors, the hosts associated with radio emission are primarily a mixture of elliptical galaxies, QSOs, and LIRGs, which are in good agreement with previous studies. The full catalog of radio lobes and their host galaxies will meas... 4. Simple Stellar Population Modeling of Low S/N Galaxy Spectra and Quasar Host Galaxy Applications Mosby, Gregory; Hooper, Eric; Wolf, Marsha; Sheinis, Andrew; Richards, Joseph 2014-01-01 To study the effect of supermassive black holes (SMBHs) on their host galaxies it is important to study the hosts when the SMBH is near its peak activity. A method to investigate the host galaxies of high luminosity quasars is to obtain optical spectra at positions offset from the nucleus where the relative contribution of the quasar and host are comparable. However, at these extended radii the galaxy surface brightness is often low (20-22 mag per arcsec$^{2}$) and the resulting spectrum might have such low S/N that it hinders analysis with standard stellar population modeling techniques. To address this problem we have developed a method that can recover galaxy star formation histories (SFHs) from rest frame optical spectra with S/N$\\sim$5~\\AA$^{-1}$. This method uses the statistical technique diffusion k-means to tailor the stellar population modeling basis set. Our diffusion k-means minimal basis set, composed of 4 broad age bins, is successful in recovering a range of galaxy SFHs. Additionally, using an... 5. H{\\alpha} Imaging of Nearby Seyfert Host Galaxies Theios, R L; Ross, N R 2016-01-01 We used narrowband interference filters with the CCD imaging camera on the Nickel 1.0 meter telescope at Lick Observatory to observe 31 nearby (z < 0.03) Seyfert galaxies in the 12 {\\mu}m Active Galaxy Sample. We obtained pure emission line images of each galaxy in order to separate H{\\alpha} emission from the nucleus from that of the host galaxy. The extended H{\\alpha} emission is expected to be powered by newly formed hot stars, and correlates well with other indicators of current star formation in these galaxies: 7.7 {\\mu}m PAH, far-infrared, and radio luminosity. Relative to what would be expected from recent star formation, there is a 0.8 dex excess of radio emission in our Seyfert galaxies. The nuclear H{\\alpha} luminosity is dominated by the AGN, and is correlated with the hard X-ray luminosity. There is an upward offset of 1 dex in this correlation for the Seyfert 1s due to a strong contribution from the Broad Line Region. We found a correlation between star formation rate and AGN luminosity. In sp... 6. Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies Kormendy, John 2013-01-01 We review the observed demographics and inferred evolution of supermassive black holes (BHs) found by dynamical modeling of spatially resolved kinematics. Most influential was the discovery of a tight correlation between BH mass and the velocity dispersion of the host-galaxy bulge. It and other correlations led to the belief that BHs and bulges coevolve by regulating each other's growth. New results are now replacing this simple story with a richer and more plausible picture in which BHs correlate differently with different galaxy components. BHs are found in pure-disk galaxies, so classical (elliptical-galaxy-like) bulges are not necessary to grow BHs. But BHs do not correlate with galaxy disks. And any correlations with disk-grown pseudobulges or halo dark matter are so weak as to imply no close coevolution. We suggest that there are four regimes of BH feedback. 1- Local, stochastic feeding of small BHs in mainly bulgeless galaxies involves too little energy to result in coevolution. 2- Global feeding in ma... 7. The Role of Host Galaxy for the Environmental Dependence of Active Nuclei in Local Galaxies Davies, Richard I.; Hicks, E. K. S.; Erwin, P.; Burtscher, L.; Contursi, A.; Genzel, R.; Janssen, A.; Koss, M.; Lin, M.-Y.; Lutz, D.; Maciejewski, W.; Müller-Sánchez, F.; Orban de Xivry, G.; Ricci, C.; Riffel, R.; Riffel, R. A.; Rosario, D.; Schartmann, M.; Schnorr-Müller, A.; Shimizu, T.; Sternberg, A.; Sturm, E.; Storchi-Bergmann, T.; Tacconi, L.; Veilleux, S. 2017-01-01 We discuss the environment of local hard X-ray selected active galaxies, with reference to two independent group catalogues. We find that the fraction of these AGN in S0 host galaxies decreases strongly as a function of galaxy group size (halo mass) - which contrasts with the increasing fraction of galaxies of S0 type in denser environments. However, there is no evidence for an environmental dependence of AGN in spiral galaxies. Because most AGN are found in spiral galaxies, this dilutes the signature of environmental dependence for the population as a whole. We argue that the differing results for AGN in disk-dominated and bulge-dominated galaxies is related to the source of the gas fuelling the AGN, and so may also impact the luminosity function, duty cycle, and obscuration. We find that there is a significant difference in the luminosity function for AGN in spiral and S0 galaxies, and tentative evidence for some difference in the fraction of obscured AGN. 8. The Role of Host Galaxy for the Environmental Dependence of Active Nuclei in Local Galaxies Davies, R I; Erwin, P; Burtscher, L; Contursi, A; Genzel, R; Janssen, A; Koss, M; Lin, M -Y; Lutz, D; Maciejewski, W; Mueller-Sanchez, F; de Xivry, G Orban; Ricci, C; Riffel, R; Riffel, R A; Rosario, D; Schartmann, M; Schnorr-Mueller, A; Shimizu, T; Sternberg, A; Sturm, E; Storchi-Bergmann, T; Tacconi, L; Veilleux, S 2016-01-01 We discuss the environment of local hard X-ray selected active galaxies, with reference to two independent group catalogues. We find that the fraction of these AGN in S0 host galaxies decreases strongly as a function of galaxy group size (halo mass) - which contrasts with the increasing fraction of galaxies of S0 type in denser environments. However, there is no evidence for an environmental dependence of AGN in spiral galaxies. Because most AGN are found in spiral galaxies, this dilutes the signature of environmental dependence for the population as a whole. We argue that the differing results for AGN in disk-dominated and bulge-dominated galaxies is related to the source of the gas fuelling the AGN, and so may also impact the luminosity function, duty cycle, and obscuration. We find that there is a significant difference in the luminosity function for AGN in spiral and S0 galaxies, and tentative evidence for some difference in the fraction of obscured AGN. 9. The star formation rates of active galactic nuclei host galaxies Ellison, Sara L; Rosario, David J; Mendel, J Trevor 2016-01-01 Using artificial neural network (ANN) predictions of total infra-red luminosities (LIR), we compare the host galaxy star formation rates (SFRs) of ~21,000 optically selected active galactic nuclei (AGN), 466 low excitation radio galaxies (LERGs) and 721 mid-IR selected AGN. SFR offsets (Delta SFR) relative to a sample of star-forming main sequence' galaxies (matched in M*, z and local environment) are computed for the AGN hosts. Optically selected AGN exhibit a wide range of Delta SFR, with a distribution skewed to low SFRs and a median Delta SFR = -0.06 dex. The LERGs have SFRs that are shifted to even lower values with a median Delta SFR = -0.5 dex. In contrast, mid-IR selected AGN have, on average, SFRs enhanced by a factor ~1.5. We interpret the different distributions of Delta SFR amongst the different AGN classes in the context of the relative contribution of triggering by galaxy mergers. Whereas the LERGs are predominantly fuelled through low accretion rate secular processes which are not accompanied ... 10. Are Some Milky Way Globular Clusters Hosted by Undiscovered Galaxies? Zaritsky, Dennis; Sand, David J 2016-01-01 The confirmation of a globular cluster (GC) in the recently discovered ultrafaint galaxy Eridanus II (Eri II) motivated us to examine the question posed in the title. After estimating the halo mass of Eri II using a published stellar mass - halo mass relation, the one GC in this galaxy supports extending the relationship between the number of GCs hosted by a galaxy and the galaxy's total mass about two orders of magnitude in stellar mass below the previous limit. For this empirically determined specific frequency of between 0.06 and 0.39 globular clusters per 10$^9M_\\odot$of total mass, the surviving Milky Way (MW) subhalos with masses smaller than$10^{10} M_\\odot$could host as many as 5 to 31 GCs, broadly consistent with the actual population of outer halo MW GCs, although matching the radial distribution in detail remains a challenge. Using a subhalo mass function from published high resolution numerical simulations and a Poissonian model for populating those halos with the aforementioned empirically ... 11. What are the galaxies that host MIR-selected AGN? Rosario, David 2016-08-01 Infra-red selection techniques, sensitive to dust strongly heated by an AGN, offer a way to identify some of the most obscured accretion events in the Universe. I will describe the results of a comprehensive multi-wavelength study of AGN to z>2 selected using Spitzer/IRAC based methods in the COSMOS field. Armed with AGN-optimised redshifts and stellar masses, we explore the dust emission from the active nucleus and the host galaxy. We demonstrate that IR-selected AGN tend to be found in low mass host galaxies, when compared to other AGN identification methods. The star-formation rates of obscured and unobscured IR-selected AGN are very similar, implying that large-scale obscuration with co-eval star-bursts are not found in a major proportion of heavily obscured AGN. 12. Infrared Characters of Host Galaxies with H2O Megamaser 俞志尧 2001-01-01 Infrared characters of all the host galaxies with the H2O megamaser have been studied. The most striking featureis the anticorrelation of S(60)/S(100) versus S(12)/S(25), and S(25)/S(60) versus S(12)/S(25). The anticorrelationin the tlux density ratio can been explained by coexistence of large and very small dust particles. The latter, whichare heated by absorption of single photon, are believed to be responsible for the bulk of 12μm radiation. If thephoton energy of the host galaxy is small, this implies large S(12)/S(25) and small S(60)/S(100). However, whenphoton energy density becomes larger, the infrared spectrum will peak at wavelengths ≤ 100 μm and enhanceemission at 25 μm. As a consequence small S(12)/S(25) and large S(60)/S(100) are observed. 13. Locating star-forming regions in quasar host galaxies Young, J. E.; Eracleous, M.; Shemmer, O.; Netzer, H.; Gronwall, C.; Lutz, Dieter; Ciardullo, R.; Sturm, Eckhard 2014-02-01 We present a study of the morphology and intensity of star formation in the host galaxies of eight Palomar-Green quasars using observations with the Hubble Space Telescope. Our observations are motivated by recent evidence for a close relationship between black hole growth and the stellar mass evolution in its host galaxy. We use narrow-band [O II]λ3727, Hβ, [O III]λ5007 and Paα images, taken with the Wide Field Planetary Camera 2 and NICMOS instruments, to map the morphology of line-emitting regions, and, after extinction corrections, diagnose the excitation mechanism and infer star-formation rates. Significant challenges in this type of work are the separation of the quasar light from the stellar continuum and the quasar-excited gas from the star-forming regions. To this end, we present a novel technique for image decomposition and subtraction of quasar light. Our primary result is the detection of extended line-emitting regions with sizes ranging from 0.5 to 5 kpc and distributed symmetrically around the nucleus, powered primarily by star formation. We determine star-formation rates of the order of a few tens of M⊙ yr-1. The host galaxies of our target quasars have stellar masses of the order of 1011 M⊙ and specific star-formation rates on a par with those of M82 and luminous infrared galaxies. As such they fall at the upper envelope or just above the star-formation mass sequence in the specific star formation versus stellar mass diagram. We see a clear trend of increasing star-formation rate with quasar luminosity, reinforcing the link between the growth of the stellar mass of the host and the black hole mass found by other authors. 14. Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies Kormendy, John; Ho, Luis C. 2013-01-01 We review the observed demographics and inferred evolution of supermassive black holes (BHs) found by dynamical modeling of spatially resolved kinematics. Most influential was the discovery of a tight correlation between BH mass and the velocity dispersion of the host-galaxy bulge. It and other correlations led to the belief that BHs and bulges coevolve by regulating each other's growth. New results are now replacing this simple story with a richer and more plausible picture in which BHs corr... 15. Supermassive black holes and their host spheroids I. Galaxy vivisection Savorgnan, Giulia A D 2015-01-01 Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using$3.6 \\rm ~\\mu mSpitzer$imagery, which is a superb tracer of the stellar mass (superior to the$K$-band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, contains a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and - for the first time - 2D kinematics, we were able to account for sph... 16. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. I. DISASSEMBLING GALAXIES Savorgnan, G. A. D.; Graham, A. W., E-mail: [email protected] [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia) 2016-01-15 Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using 3.6 μm Spitzer imagery, which is a superb tracer of the stellar mass (superior to the K band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, contains a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction, and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and—for the first time—2D kinematics, we were able to account for spheroids; large-scale, intermediate-scale, and nuclear disks; bars; rings; spiral arms; halos; extended or unresolved nuclear sources; and partially depleted cores. For each individual galaxy, we compared our best-fit model with previous studies, explained the discrepancies, and identified the optimal decomposition. Moreover, we have independently performed one-dimensional (1D) and two-dimensional (2D) decompositions and concluded that, at least when modeling large, nearby galaxies, 1D techniques have more advantages than 2D techniques. Finally, we developed a prescription to estimate the uncertainties on the 1D best-fit parameters for the 66 spheroids that takes into account systematic errors, unlike popular 2D codes that only consider statistical errors. 17. Host galaxies of long gamma-ray bursts in the Millennium Simulation Chisari, Nora E; Pellizza, Leonardo J 2010-01-01 We investigate the nature of the host galaxies of long Gamma-Ray bursts (LGRBs) using a galaxy catalogue constructed from the Millennium Simulation. We developed an LGRB synthetic model based on the hypothesis that LGRBs originate at the end of the life of massive stars following the collapsar model, optionally including a constraint on the metallicity of the progenitor. An observability pipeline was designed to reproduce observations from BATSE experiment and to include a probability estimation for a galaxy to be observationally identified as a host. This new tool allows us to build an observable host galaxy catalogue, required to reproduce the current stellar mass distribution of observed hosts. Systems in our observable catalogue are able to reproduce the observed properties of host galaxies, namely stellar masses, colours, luminosity, star formation activity and metallicities as a function of redshift. At z>2, our model predicts that the observable host galaxies would be very similar to the global galaxy ... 18. Revisiting The First Galaxies: The effects of Population III stars on their host galaxies Muratov, Alexander L; Gnedin, Nickolay Y; Zemp, Marcel 2012-01-01 We revisit the formation and evolution of the first galaxies using new hydrodynamic cosmological simulations with the ART code. Our simulations feature a recently developed model for H2 formation and dissociation, and a star formation recipe that is based on molecular rather than atomic gas. Here, we develop and implement a new recipe for the formation of metal-free Population III stars. We find the epoch during which Pop III stars dominated the energy and metal budget of the first galaxies to be short-lived. Galaxies which host Pop III stars do not retain dynamical signatures of their thermal and radiative feedback for more than 10^8 yr after the lives of the stars end in pair-instability supernovae, even when we consider the maximum reasonable efficiency of the feedback. Though metals ejected by the supernovae can travel well beyond the virial radius of the host galaxy, they will typically begin to fall back quickly, and do not enrich a large fraction of the intergalactic medium. Galaxies more massive than ... 19. Keck Observations of 160 Gamma-Ray Burst Host Galaxies Perley, Daniel A; Prochaska, Jason X 2013-01-01 We present a preliminary data release from our multi-year campaign at Keck Observatory to study the host galaxies of a large sample of Swift-era gamma-ray bursts via multi-color ground-based optical imaging and spectroscopy. With over 160 targets observed to date (and almost 100 host detections, most of which have not previously been reported in the literature) our effort represents the broadest GRB host survey to date. While targeting was heterogeneous, our observations span the known diversity of GRBs including short bursts, long bursts, spectrally soft GRBs (XRFs), ultra-energetic GRBs, X-ray faint GRBs, dark GRBs, SN-GRBs, and other sub-classes. We also present a preview of our database (currently available online via a convenient web interface) including a catalog of multi-color photometry, redshifts and line ID's. Final photometry and reduced imaging and spectra will be available in the near future. 20. Fast outflows and star formation quenching in quasar host galaxies Carniani, S; Maiolino, R; Balmaverde, B; Brusa, M; Cano-Díaz, M; Cicone, C; Comastri, A; Cresci, G; Fiore, F; Feruglio, C; La Franca, F; Mainieri, V; Mannucci, F; Nagao, T; Netzer, H; Piconcelli, E; Risaliti, G; Schneider, R; Shemmer, O 2016-01-01 Negative feedback from active galactic nuclei (AGN) is considered a key mechanism in shaping galaxy evolution. Fast, extended outflows are frequently detected in the AGN host galaxies at all redshifts and luminosities, both in ionised and molecular gas. However, these outflows are only "potentially" able to quench star formation and we are still missing a decisive evidence of negative feedback in action. Here we present Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) H- and K-band integral-field spectroscopic observations of two quasars at$z\\sim$2.4 characterised by fast, extended outflows detected through the [OIII]$\\lambda$5007 line (Carniani et al. 2015). The high signal-to-noise ratio of our observations allows us to identify faint narrow (FWHM$< 500$km/s), and spatially extended components in [OIII]$\\lambda$5007 and H$\\alpha$emission associated with star formation in the host galaxy. Such star-formation powered emission is spatially anti-correlated with the fast outflow... 1. The MOSDEF Survey: AGN Multi-wavelength Identification, Selection Biases, and Host Galaxy Properties Azadi, Mojegan; Coil, Alison L.; Aird, James; Reddy, Naveen; Shapley, Alice; Freeman, William R.; Kriek, Mariska; Leung, Gene C. K.; Mobasher, Bahram; Price, Sedona H.; Sanders, Ryan L.; Shivaei, Irene; Siana, Brian 2017-01-01 We present results from the MOSFIRE Deep Evolution Field (MOSDEF) survey on the identification, selection biases, and host galaxy properties of 55 X-ray, IR, and optically selected active galactic nuclei (AGNs) at 1.4optical spectra of galaxies and AGNs and use the BPT diagram to identify optical AGNs. We examine the uniqueness and overlap of the AGNs identified at different wavelengths. There is a strong bias against identifying AGNs at any wavelength in low-mass galaxies, and an additional bias against identifying IR AGNs in the most massive galaxies. AGN hosts span a wide range of star formation rates (SFRs), similar to inactive galaxies once stellar mass selection effects are accounted for. However, we find (at ∼2–3σ significance) that IR AGNs are in less dusty galaxies with relatively higher SFR and optical AGNs in dusty galaxies with relatively lower SFR. X-ray AGN selection does not display a bias with host galaxy SFR. These results are consistent with those from larger studies at lower redshifts. Within star-forming galaxies, once selection biases are accounted for, we find AGNs in galaxies with similar physical properties as inactive galaxies, with no evidence for AGN activity in particular types of galaxies. This is consistent with AGNs being fueled stochastically in any star-forming host galaxy. We do not detect a significant correlation between SFR and AGN luminosity for individual AGN hosts, which may indicate the timescale difference between the growth of galaxies and their supermassive black holes. 2. The host galaxy and environment of a neutron star merger Postigo, A de Ugarte; Rowlinson, A; Garcia-Benito, R; Levan, A J; Gorosabel, J; Goldoni, P; Schulze, S; Zafar, T; Wiersema, K; Sanchez-Ramirez, R; Melandri, A; D'Avanzo, P; Oates, S; D'Elia, V; De Pasquale, M; Kruehler, T; van der Horst, A J; Xu, D; Watson, D; Piranomonte, S; Vergani, S; Milvang-Jensen, B; Kaper, L; Malesani, D; Fynbo, J P U; Cano, Z; Covino, S; Flores, H; Greiss, S; Hammer, F; Hartoog, O E; Hellmich, S; Heuser, C; Hjorth, J; Jakobsson, P; Mottola, S; Sparre, M; Sollerman, J; Tagliaferri, G; Tanvir, N R; Vestergaard, M; Wijers, R A M J 2013-01-01 The mergers of neutron stars have been predicted to cause an r-process supernova - a luminous near-infrared transient powered by the radioactive decay of freshly formed heavy metals. An r-process supernova, or kilonova, has recently been discovered coincident with the short-duration gamma-ray burst GRB 130603B, simultaneously confirming the widely-held theory of the origin of most short-durations GRBs in neutron star mergers. We report here the absorption spectrum of the afterglow of this GRB. From it we determine the redshift of the burst and the properties of the host galaxy and the environment in which the merger occurred. The merger is not associated with the most star-forming region of the galaxy; however, it did occur in a dense region, implying a rapid merger or a low natal kick velocity for the neutron star binary. 3. Herschel Observed Stripe 82 Quasars and Their Host Galaxies: Connections between AGN Activity and host Galaxy Star Formation Dong, X. Y.; Wu, Xue-Bing 2016-06-01 In this work, we present a study of 207 quasars selected from the Sloan Digital Sky Survey quasar catalogs and the Herschel Stripe 82 survey. Quasars within this sample are high-luminosity quasars with a mean bolometric luminosity of 1046.4 erg s-1. The redshift range of this sample is within z luminosity, far-IR (FIR) luminosity, stellar mass, as well as many other AGN and galaxy properties are deduced from the SED fitting results. The mean star formation rate (SFR) of the sample is 419 M ⊙ yr-1 and the mean gas mass is ˜1011.3 M ⊙. All of these results point to an IR luminous quasar system. Compared with star formation main sequence (MS) galaxies, at least 80 out of 207 quasars are hosted by starburst galaxies. This supports the statement that luminous AGNs are more likely to be associated with major mergers. The SFR increases with the redshift up to z = 2. It is correlated with the AGN bolometric luminosity, where {L}{{FIR}}\\propto {L}{{Bol}}0.46+/- 0.03. The AGN bolometric luminosity is also correlated with the host galaxy mass and gas mass. Yet the correlation between L FIR and L Bol has higher significant level, implies that the link between AGN accretion and the SFR is more primal. The M BH/M * ratio of our sample is 0.02, higher than the value 0.005 in the local universe. It might indicate an evolutionary trend of the M BH-M * scaling relation. 4. The host galaxy of a fast radio burst. Keane, E F; Johnston, S; Bhandari, S; Barr, E; Bhat, N D R; Burgay, M; Caleb, M; Flynn, C; Jameson, A; Kramer, M; Petroff, E; Possenti, A; van Straten, W; Bailes, M; Burke-Spolaor, S; Eatough, R P; Stappers, B W; Totani, T; Honma, M; Furusawa, H; Hattori, T; Morokuma, T; Niino, Y; Sugai, H; Terai, T; Tominaga, N; Yamasaki, S; Yasuda, N; Allen, R; Cooke, J; Jencson, J; Kasliwal, M M; Kaplan, D L; Tingay, S J; Williams, A; Wayth, R; Chandra, P; Perrodin, D; Berezina, M; Mickaliger, M; Bassa, C 2016-02-25 In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations. Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of ΩIGM = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe, and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst, and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts. 5. The host galaxies of micro-Jansky radio sources Luchsinger, K M; Jones, K M; Mauduit, J C; Pforr, J; Surace, J A; Vaccari, M; Farrah, D; Gonzales-Solares, E; Jarvis, M J; Maraston, C; Marchetti, L; Oliver, S; Afonso, J; Cappozi, D; Sajina, A 2015-01-01 We combine a deep 0.5~deg$^2$, 1.4~GHz deep radio survey in the Lockman Hole with infrared and optical data in the same field, including the SERVS and UKIDSS near-infrared surveys, to make the largest study to date of the host galaxies of radio sources with typical radio flux densities$\\sim 50 \\;\\mu$Jy. 87% (1274/1467) of radio sources have identifications in SERVS to$AB\\approx 23.1$at 3.6 or 4.5$\\mu$m, and 9% are blended with bright objects (mostly stars), leaving only 4% (59 objects) which are too faint to confidently identify in the near-infrared. We are able to estimate photometric redshifts for 68% of the radio sources. We use mid-infrared diagnostics to show that the source population consists of a mixture of star forming galaxies, rapidly accreting (cold mode) AGN and low accretion rate, hot mode AGN, with neither AGN nor starforming galaxies clearly dominating. We see the breakdown in the$K-z$relation in faint radio source samples, and show that it is due to radio source populations becoming domi... 6. Host Galaxies of Type Ia Supernovae from the Nearby Supernova Factory Childress, M.; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey, S.; Baltay, C.; Bongard, S.; Buton, C.; Canto, A.; Cellier-Holzem, F.; Chotard, N.; Copin, Y.; Fakhouri, H. K.; Gangler, E.; Guy, J.; Hsiao, E. Y.; Kerschhaggl, M.; Kim, A. G.; Kowalski, M.; Loken, S.; Nugent, P.; Paech, K.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigault, M.; Runge, K.; Scalzo, R.; Smadja, G.; Tao, C.; Thomas, R. C.; Weaver, B. A.; Wu, C. 2013-06-01 We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and Hα-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M */M ⊙) > 8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies. 7. HOST GALAXIES OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others 2013-06-20 We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and H{alpha}-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M{sub *}/M{sub Sun }) > 8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies. 8. Locating Star-Forming Regions in Quasar Host Galaxies Young, J E; Shemmer, O; Netzer, H; Gronwall, C; Lutz, Dieter; Ciardullo, R; Sturm, Eckhard 2013-01-01 We present a study of the morphology and intensity of star formation in the host galaxies of eight Palomar-Green quasars using observations with the Hubble Space Telescope. Our observations are motivated by recent evidence for a close relationship between black hole growth and the stellar mass evolution in its host galaxy. We use narrow-band [O II]$\\lambda$3727, H$\\beta$, [O III]$\\lambda$5007 and Pa$\\alpha$images, taken with the WFPC2 and NICMOS instruments, to map the morphology of line-emitting regions, and, after extinction corrections, diagnose the excitation mechanism and infer star-formation rates. Significant challenges in this type of work are the separation of the quasar light from the stellar continuum and the quasar-excited gas from the star-forming regions. To this end, we present a novel technique for image decomposition and subtraction of quasar light. Our primary result is the detection of extended line-emitting regions with sizes ranging from 0.5 to 5 kpc and distributed symmetrically aroun... 9. Correlations between Supermassive Black Holes and their Hosts in Active Galaxies Busch, Gerold 2016-01-01 In the last decades several correlations between the mass of the central supermassive black hole (BH) and properties of the host galaxy - such as bulge luminosity and mass, central stellar velocity dispersion, S\\'ersic index, spiral pitch angle etc. - have been found and point at a coevolution scenario of BH and host galaxy. In this article, I review some of these relations for inactive galaxies and discuss the findings for galaxies that host an active galactic nucleus/quasar. I present the results of our group that finds that active galaxies at$z\\lesssim 0.1$do not follow the BH mass - bulge luminosity relation. Furthermore, I show near-infrared integral-field spectroscopic data that suggest that young stellar populations cause the bulge overluminosity and indicate that the host galaxy growth started first. Finally, I discuss implications for the BH-host coevolution. 10. X-Ray Groups of Galaxies at 0.5 Tanaka, Masayuki; Finoguenov, Alexis; Lilly, Simon J.; Bolzonella, Micol; Carollo, C. Marcella; Contini, Thierry; Iovino, Angela; Kneib, Jean-Paul; Lamareille, Fabrice; Le Fevre, Olivier; Mainieri, Vincenzo; Presotto, Valentina; Renzini, Alvio; Scodeggio, Marco; Silverman, John D.; Zamorani, Gianni; Bardelli, Sandro; Bongiorno, Angela; Caputi, Karina; Cucciati, Olga; de la Torre, Sylvain; de Ravel, Loic; Franzetti, Paolo; Garilli, Bianca; Kampczyk, Pawel; Knobel, Christian; Kovac, Katarina; Le Borgne, Jean-Francois; Le Brun, Vincent; Lopez-Sanjuan, Carlos; Maier, Christian; Mignoli, Marco; Pello, Roser; Peng, Yingjie; Perez-Montero, Enrique; Tasca, Lidia; Tresse, Laurence; Vergani, Daniela; Zucca, Elena; Barnes, Luke; Bordoloi, Rongmon; Cappi, Alberto; Cimatti, Andrea; Coppa, Graziano; Koekemoer, Anton M.; McCracken, Henry J.; Moresco, Michele; Nair, Preethi; Oesch, Pascal; Pozzetti, Lucia; Welikala, Niraj 2012-01-01 We present a photometric and spectroscopic study of galaxies at 0.5 zCOSMOS survey. There is a fair amount of evidence that galaxy properties depend on the mass of groups and clusters, in the sense that quiescent galaxies prefer more 11. The Hubble Space Telescope Survey of BL Lacertae Objects. IV. Infrared Imaging of Host Galaxies Scarpa, Riccardo; Urry, C. Megan; Padovani, Paolo; Calzetti, Daniela; O'Dowd, Matthew 2000-11-01 The Hubble Space Telescope NICMOS Camera 2 was used for H-band imaging of 12 BL Lacertae objects taken from the larger sample observed with the WFPC2 in the R band by Urry and coworkers and Scarpa and coworkers. Ten of the 12 BL Lacs are clearly resolved, and the detected host galaxies are large, bright ellipticals with average absolute magnitude =-26.2+/-0.45 mag and effective radius =10+/-5 kpc. The rest-frame integrated color of the host galaxies is on average =2.3+/-0.3, consistent with the value for both radio galaxies and normal, nonactive elliptical galaxies and indicating that the dominant stellar population is old. The host galaxies tend to be bluer in their outer regions than in their cores, with average color gradient Δ(R-H)/Δlogr=-0.2 mag, again consistent with results for normal nonactive elliptical galaxies. The infrared Kormendy relation, derived for the first time for BL Lac host galaxies, is μe=3.8logre+14.8, fully in agreement with the relation for normal ellipticals. The close similarity between BL Lac host galaxies and normal ellipticals suggests that the active nucleus has surprisingly little effect on the host galaxy. This supports a picture in which all elliptical galaxies harbor black holes that can be actively accreting for some fraction of their lifetime. 12. X-Ray bright active galactic nuclei in massive galaxy clusters - II. The fraction of galaxies hosting active nuclei Ehlert, S.; von der Linden, A.; Allen, S. W. 2013-01-01 We present a measurement of the fraction of cluster galaxies hosting X-ray bright active galactic nuclei (AGN) as a function of clustercentric distance scaled in units of r500. Our analysis employs high-quality Chandra X-ray and Subaru optical imaging for 42 massive X-ray-selected galaxy cluster... 13. Type Ia Supernova Hubble Residuals and Host-Galaxy Properties Kim, A G; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Feindt, U; Fleury, M; Gangler, E; Greskovic, P; Guy, J; Kowalski, M; Lombardo, S; Nordin, J; Nugent, P; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Runge, K; Saunders, C; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A 2014-01-01 Kim et al. (2013) [K13] introduced a new methodology for determining peak-brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spectrophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is$0.013\\pm 0.031$mag for a supernova subsample with data coverage corresponding to the K13 training; at$\\ll 1\\sigma$, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement the Hubble residual step with host mass is$0.045\\pm 0.026$mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch para... 14. A multi-colour study of the dark GRB 000210 host galaxy and its environment Gorosabel, J.; Christensen, Lise; Hjorth, J.; 2003-01-01 We present UBVRIZJsHKs broad band photometry of the host galaxy of the dark gamma-ray burst (GRB) of February 10, 2000. These observations represent the most exhaustive photometry given to date of any GRB host galaxy. A grid of spectral templates have been fitted to the Spectral Energy Distributi... 15. Host Galaxy Spectra and Consequences for SN Typing from the SDSS SN Survey Olmstead, Matthew D.; Brown, Peter J.; Sako, Masao; Bassett, Bruce; Bizyaev, Dmitry; Brinkmann, J.; Brownstein, Joel R.; Brewington, Howard; Campbell, Heather; D’Andrea, Chris B.; Dawson, Kyle S.; Ebelke, Garrett L.; Frieman, Joshua A.; Galbany, Lluís; Garnavich, Peter; Gupta, Ravi R.; Hlozek, Renee; Jha, Saurabh W.; Kunz, Martin; Lampeitl, Hubert; Malanushenko, Elena; Malanushenko, Viktor; Marriner, John; Miquel, Ramon; Montero-Dorta, Antonio D.; Nichol, Robert C.; Oravetz, Daniel J.; Pan, Kaike; Schneider, Donald P.; Simmons, Audrey E.; Smith, Mathew; Snedden, Stephanie A. 2014-03-06 We present the spectroscopy from 5254 galaxies that hosted supernovae (SNe) or other transient events in the Sloan Digital Sky Survey II (SDSS-II). Obtained during SDSS-I, SDSS-II, and the Baryon Oscillation Spectroscopic Survey (BOSS), this sample represents the largest systematic, unbiased, magnitude limited spectroscopic survey of supernova (SN) host galaxies. Using the host galaxy redshifts, we test the impact of photometric SN classification based on SDSS imaging data with and without using spectroscopic redshifts of the host galaxies. Following our suggested scheme, there are a total of 1166 photometrically classified SNe Ia when using a flat redshift prior and 1126 SNe Ia when the host spectroscopic redshift is assumed. For 1024 (87.8%) candidates classified as likely SNe Ia without redshift information, we find that the classification is unchanged when adding the host galaxy redshift. Using photometry from SDSS imaging data and the host galaxy spectra, we also report host galaxy properties for use in future nalysis of SN astrophysics. Finally, we investigate the differences in the interpretation of the light curve properties with and without knowledge of the redshift. When using the SALT2 light curve fitter, we find a 21% increase in the number of fits that converge when using the spectroscopic redshift. Without host galaxy redshifts, we find that SALT2 light curve fits are systematically biased towards lower photometric redshift estimates and redder colors in the limit of low signal-to-noise data. The general improvements in performance of the light curve fitter and the increased diversity of the host galaxy sample highlights the importance of host galaxy spectroscopy for current photometric SN surveys such as the Dark Energy Survey and future surveys such as the Large Synoptic Survey Telescope. 16. VizieR Online Data Catalog: Properties of SN host galaxies (Kelly+, 2014) Kelly, P. L.; Filippenko, A. V.; Modjaz, M.; Kocevski, D. 2017-03-01 We study the host galaxies of both nearby (zsearches (e.g., the Palomar Transient Factory (PTF); Rau et al., 2009PASP..121.1334R; Law et al., 2009PASP..121.1395L), which do not target specific potential hosts or z<1.2 LGRBs detected by gamma-ray satellites. We use the SDSS spectroscopic sample to build a control sample of low-redshift star-forming galaxies and SDSS photometry and spectroscopy to measure properties of both the sample of low-redshift star-forming galaxies and the host galaxies of the nearby SNe. For the host galaxies of z<1.2 LGRBs, we estimate host properties using published photometry and HST imaging. (2 data files). 17. The afterglow and the host galaxy of GRB 011211 Jakobsson, P; Fynbo, J P U; Gorosabel, J; Pedersen, K; Burud, I; Levan, A J; Kouveliotou, C; Tanvir, N R; Fruchter, A S; Rhoads, J; Grav, T; Hansen, M W; Michelsen, R; Andersen, M I; Jensen, B L; Pedersen, H; Thomsen, B; Weidinger, M; Bhargavi, S G; Cowsik, R; Pandey, S B 2003-01-01 We present optical, near-infrared, and X-ray observations of the optical afterglow (OA) of the X-ray rich, long-duration gamma-ray burst GRB 011211. Hubble Space Telescope (HST) data obtained 14, 26, 32, and 59 days after the burst, show the host galaxy to have a morphology that is fairly typical of blue galaxies at high redshift. We measure its magnitude to be R = 24.95 +/- 0.11. We detect a break in the OA R-band light curve which is naturally accounted for by a collimated outflow geometry. By fitting a broken power-law to the data we find a best fit with a break 1.56 +/- 0.02 days after the burst, a pre-break slope of alpha_1 = -0.95 +/- 0.02, and a post-break slope of alpha_2 = -2.11 +/- 0.07. The UV-optical spectral energy distribution (SED) around 14 hours after the burst is best fit with a power-law with index beta = -0.56 +/- 0.19 reddened by an SMC-like extinction law with a modest A_V = 0.08 +/- 0.08 mag. By comparison, from the XMM-Newton X-ray data at around the same time, we find a decay index of... 18. Host Galaxies of Young Dust-Reddened Quasars Urrutia, T.; Lacy, M.; Becker, R.; Glikman, E. 2009-10-01 We present results on a multiwavelength campaign to identify the nature of dust-reddened Type 1 quasars. These quasars were selected by matching FIRST, 2MASS and very red optical counterparts with r'-K > 5. We find a very high fraction of Low Ionization Broad Absorption Line Quasars (LoBALs) among AGN selected with this method, perhaps a sign of quasar feedback. From X-ray observations and Balmer decrement measurements, the obscuring dust is most likely located in a cold absorber such as the host galaxy, rather than from a torus near the AGN. Hubble ACS imaging of a sub-sample of these sources showed a very high fraction of interacting and merging systems. The quasars appear to be very young in which dust from the merging galaxies is still settling in. Spitzer IRS and MIPS data show star formation signatures and deep Silicate absorption features in these objects, but overall the quasar is the dominant source in the Mid-infrared. 19. High-redshift quasar host galaxies with adaptive optics Kuhlbrodt, B; Wisotzki, L; Jahnke, K 2005-01-01 We present K band adaptive optics observations of three high-redshift (z ~ 2.2) high-luminosity quasars, all of which were studied for the first time. We also bserved several point spread function (PSF) calibrators, non-simultaneously because of the small field of view. The significant temporal PSF variations on timescales of minutes inhibited a straightforward scaled PSF removal from the quasar images. Characterising the degree of PSF concentration by the radii encircling 20% and 80% of the total flux, respectively, we found that even under very different observing conditions the r20 vs. r80 relation varied coherently between individual short exposure images, delineating a well-defined relation for point sources. Placing the quasar images on this relation, we see indications that all three objects were resolved. We designed a procedure to estimate the significance of this result, and to estimate host galaxy parameters, by reproducing the statistical distribution of the individual short exposure images. We fi... 20. The Host Galaxies of Nearby, Optically Luminous, AGN Petric, Andreea 2016-01-01 Coevolution of galaxies and their central black holes (BH) has been the central theme of much of recent extragalactic astronomical research. Observations of the dynamics of stars and gas in the nuclear regions of nearby galaxies suggest that the majority of spheroidal galaxies in the local Universe contain massive BHs and that the masses of those central BH correlate with the velocity dispersions of the stars in the spheroid and the bulge luminosity. Cold ISM is the basic fuel for star-formation and BH growth so its study is essential to understanding how galaxies evolve.I will present high sensitivity observations taken with the Herschel Space Observatory to measure the cold dust content in a sample of 85 nearby (z measurements from the Two Micron All Sky Survey and the Wide-Field Infrared Survey Explorer to determine their IR spectral energy distributions which we use to assess and compare the aggregate dust properties of QSO1s and QSO2s. I will also present NIR spectroscopy obtained with Gemini's Near-Infrared Spectrograph of a sub-sample of QSO2s and QSO1s which I use to compare the ratio of cold to warm H2 gas that emits in the NIR in the hosts of QSO1s and QSO2s.Finally I will present a comparison of star-formation in QSO1s and QSO2s. For both QSO1s and QSO2s 3stimates of star-formation rates that are based on the total IR continuum emission correlate with those based on the 11.3 micron PAH feature. However, for the QSO1s, star-formation rates estimated from the FIR continuum are higher than those estimated from the 11.3 micron PAH emission. This result can be attributed to a variety of factors including the possible destruction of the PAHs and that, in some sources, a fraction of the FIR originates from dust heated by the active galactic nucleus and by old stars. For QSO2s the SFR derived from the 11.3 micron PAH feature match those derived from the 160micron emission. 1. EARLY-TYPE HOST GALAXIES OF TYPE Ia SUPERNOVAE. I. EVIDENCE FOR DOWNSIZING Kang, Yijung; Kim, Young-Lo; Lim, Dongwook; Chung, Chul; Lee, Young-Wook, E-mail: [email protected] [Center for Galaxy Evolution Research and Department of Astronomy, Yonsei University, Seoul 03722 (Korea, Republic of) 2016-03-15 Type Ia supernova (SN Ia) cosmology provides the most direct evidence for the presence of dark energy. This result is based on the assumption that the lookback time evolution of SN Ia luminosity, after light curve corrections, would be negligible. Recent studies show, however, that the Hubble residual (HR) of SN Ia is correlated with the mass and morphology of host galaxies, implying the possible dependence of SN Ia luminosity on host galaxy properties. In order to investigate this more directly, we have initiated a spectroscopic survey for early-type host galaxies, for which population age and metallicity can be more reliably determined from the absorption lines. In this first paper of the series, we present here the results from high signal-to-noise ratio (≳100 per pixel) spectra for 27 nearby host galaxies in the southern hemisphere. For the first time in host galaxy studies, we find a significant (∼3.9σ) correlation between host galaxy mass (velocity dispersion) and population age, which is consistent with the “downsizing” trend among non-host early-type galaxies. This result is rather insensitive to the choice of population synthesis models. Since we find no correlation with metallicity, our result suggests that stellar population age is mainly responsible for the relation between host mass and HR. If confirmed, this would imply that the luminosity evolution plays a major role in the systematic uncertainties of SN Ia cosmology. 2. On the Host Galaxy of GRB 150101B and the Associated Active Galactic Nucleus Xie, Chen; Wang, Junfeng; Liu, Tong; Jiang, Xiaochuan 2016-01-01 We present a multi-wavelength analysis of the host galaxy of short-duration gamma-ray burst (GRB) 150101B. Follow-up optical and X-ray observations suggested that the host galaxy, 2MASX J12320498-1056010, likely harbors a low-luminosity active galactic nuclei (AGN). Our modeling of the spectral energy distribution (SED) has confirmed the nature of the AGN, making it the first reported GRB host that contains an AGN. We have also found the host galaxy is a massive elliptical galaxy with stellar population of$\\sim 5.7\\ Gyr$, one of the oldest among the short-duration GRB hosts. Our analysis suggests that the host galaxy can be classified as an X-ray bright, optically normal galaxy (XBONG), and the central AGN is likely dominated by a radiatively inefficient accretion flow (RIAF). Our work explores interesting connection that may exist between GRB and AGN activities of the host galaxy, which can help understand the host environment of the GRB events and the roles of AGN feedback. 3. Host Galaxies of Gamma-Ray Bursts and their Cosmological Evolution Courty, S; Gudmundsson, E H 2004-01-01 We use numerical simulations of large scale structure formation to explore the cosmological properties of Gamma-Ray Burst (GRB) host galaxies. Among the different sub-populations found in the simulations, we identify the host galaxies as the most efficient star-forming objects, i.e. galaxies with high specific star formation rates. We find that the host candidates are low-mass, young galaxies with low to moderate star formation rate. These properties are consistent with those observed in GRB hosts, most of which are sub-luminous, blue galaxies. Assuming that host candidates are galaxies with high star formation rates would have given conclusions inconsistent with the observations. The specific star formation rate, given a galaxy mass, is shown to increase as the redshift increases. The low mass of the putative hosts makes them difficult to detect with present day telescopes and the probability density function of the specific star formation rate is predicted to change depending on whether or not these galaxie... 4. Type Ia supernova Hubble residuals and host-galaxy properties Kim, A. G.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Fleury, M.; Guy, J. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Feindt, U.; Greskovic, P.; Kowalski, M. [Physikalisches Institut, Universität Bonn, Nußallee 12, D-53115 Bonn (Germany); Childress, M. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Chotard, N.; Copin, Y.; Gangler, E. [Université de Lyon, F-69622 Lyon (France); Université de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon (France); and others 2014-03-20 Kim et al. introduced a new methodology for determining peak-brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spectrophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ± 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at <<1σ, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement of the Hubble residual step with the host mass is 0.045 ± 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch parameters: steps at >2σ significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light-curve width and color around peak (similar to the Δm {sub 15} and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20-30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution. 5. Type Ia Supernova Hubble Residuals and Host-Galaxy Properties Nearby Supernova Factory; Kim, A. G.; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey, S.; Baltay, C.; Bongard, S.; Buton, C.; Canto, A.; Cellier-Holzem, F.; Childress, M.; Chotard, N.; Copin, Y.; Fakhouri, H. K.; Feindt, U.; Fleury, M.; Gangler, E.; Greskovic, P.; Guy, J.; Kowalski, M.; Lombardo, S.; Nordin, J.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigault, M.; Runge, K.; Saunders, C.; Scalzo, R.; Smadja, G.; Tao, C.; Thomas, R. C.; Weaver, B. A. 2014-01-17 Kim et al. (2013) [K13] introduced a new methodology for determining peak- brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spec- trophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ? 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at ? 1?, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement the Hubble residual step with host mass is 0.045 ? 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch param- eters: Steps at> 2? significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light- curve width and color around peak (similar to the∆m15 and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20 to 30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution. 6. The host galaxy and optical light curve of the gamma-ray burst GRB 980703 Holland, S.; Fynbo, J.P.U.; Hjorth, J. 2001-01-01 We present deep HST/STIS and ground-based photometry of the host galaxy of the gamma-ray burst GRB 980703 taken 17, 551, 710, and 716 days after the burst. We find that the host is a blue, slightly over-luminous galaxy with V-gal = 23.00 +/-0.10, (V - R)(gal) = 0.43 +/-0.13, and a centre that is ......We present deep HST/STIS and ground-based photometry of the host galaxy of the gamma-ray burst GRB 980703 taken 17, 551, 710, and 716 days after the burst. We find that the host is a blue, slightly over-luminous galaxy with V-gal = 23.00 +/-0.10, (V - R)(gal) = 0.43 +/-0.13, and a centre...... 980703 with any special features in the host. The host galaxy appears to be a typical example of a compact star forming galaxy similar to those found in the Hubble Deep Field North. The R-band light curve of the optical afterglow associated with this gamma-ray burst is consistent with a single power......-law decay having a slope of alpha = 1.37 +/-0.14. Due to the bright underlying host galaxy the late time properties of the light-curve are very poorly constrained. The decay of the optical light curve is consistent with a contribution from an underlying type Ic supernova like SN1998bw, or a dust echo... 7. The host galaxy and optical light curve of the gamma-ray burst GRB 980703 Holland, S.; Fynbo, J.P.U.; Hjorth, J. 2001-01-01 We present deep HST/STIS and ground-based photometry of the host galaxy of the gamma-ray burst GRB 980703 taken 17, 551, 710, and 716 days after the burst. We find that the host is a blue, slightly over-luminous galaxy with V-gal = 23.00 +/-0.10, (V - R)(gal) = 0.43 +/-0.13, and a centre that is ......We present deep HST/STIS and ground-based photometry of the host galaxy of the gamma-ray burst GRB 980703 taken 17, 551, 710, and 716 days after the burst. We find that the host is a blue, slightly over-luminous galaxy with V-gal = 23.00 +/-0.10, (V - R)(gal) = 0.43 +/-0.13, and a centre...... 980703 with any special features in the host. The host galaxy appears to be a typical example of a compact star forming galaxy similar to those found in the Hubble Deep Field North. The R-band light curve of the optical afterglow associated with this gamma-ray burst is consistent with a single power......-law decay having a slope of alpha = 1.37 +/-0.14. Due to the bright underlying host galaxy the late time properties of the light-curve are very poorly constrained. The decay of the optical light curve is consistent with a contribution from an underlying type Ic supernova like SN1998bw, or a dust echo... 8. Physical conditions and element abundances in SN and GRB host galaxies at different redshifts Contini, M 2016-01-01 We compare the physical parameters and the relative abundances calculated throughout supernova (SN) and gamma-ray burst (GRB) host galaxies by the detailed modelling of the spectra. The results show that : 1) shock velocities are lower in long period GRB (LGRB) than in SN host galaxies. 2) O/H relative abundance in SN hosts are scattered within a range 8.0 10^5 K. Ts in LGRB hosts are 3-8 10^4 K. 4) Ha increases with the ionization parameter U. We suggest that SN-host symbiosis is stronger in terms of host galaxy activity than GRB-host in the range of energies related to the near UV - optical - near IR spectra. 9. Modeling The GRB Host Galaxy Mass Distribution: Are GRBs Unbiased Tracers of Star Formation? Kocevski, Daniel; /KIPAC, Menlo Park; West, Andrew A.; /UC, Berkeley, Astron. Dept. /MIT, MKI; Modjaz, Maryam; /UC, Berkeley, Astron. Dept. 2009-08-03 We model the mass distribution of long gamma-ray burst (GRB) host galaxies given recent results suggesting that GRBs occur in low metallicity environments. By utilizing measurements of the redshift evolution of the mass-metallicity (M-Z) relationship for galaxies, along with a sharp host metallicity cut-off suggested by Modjaz and collaborators, we estimate an upper limit on the stellar mass of a galaxy that can efficiently produce a GRB as a function of redshift. By employing consistent abundance indicators, we find that sub-solar metallicity cut-offs effectively limit GRBs to low stellar mass spirals and dwarf galaxies at low redshift. At higher redshifts, as the average metallicity of galaxies in the Universe falls, the mass range of galaxies capable of hosting a GRB broadens, with an upper bound approaching the mass of even the largest spiral galaxies. We compare these predicted limits to the growing number of published GRB host masses and find that extremely low metallicity cut-offs of 0.1 to 0.5 Z{sub {circle_dot}} are effectively ruled out by a large number of intermediate mass galaxies at low redshift. A mass function that includes a smooth decrease in the efficiency of producing GRBs in galaxies of metallicity above 12+log(O/H){sub KK04} = 8.7 can, however, accommodate a majority of the measured host galaxy masses. We find that at z {approx} 1, the peak in the observed GRB host mass distribution is inconsistent with the expected peak in the mass of galaxies harboring most of the star formation. This suggests that GRBs are metallicity biased tracers of star formation at low and intermediate redshifts, although our model predicts that this bias should disappear at higher redshifts due to the evolving metallicity content of the universe. 10. The Effect of Host Galaxies on Type Ia Supernovae in the SDSS-II Supernova Survey Lampeitl, Hubert; Nichol, Robert C; Bassett, Bruce; Cinabro, David; Dilday, Benjamin; Foley, Ryan J; Frieman, Joshua A; Garnavich, Peter M; Goobar, Ariel; Im, Myungshin; Jha, Saurabh W; Marriner, John; Miquel, Ramon; Nordin, Jakob; Östman, Linda; Riess, Adam G; Sako, Masao; Schneider, Donald P; Sollerman, Jesper; Stritzinger, Maximilian 2010-01-01 We present an analysis of the host galaxy dependencies of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We rediscover, to high significance, the strong correlation between host galaxy typeand the width of the observed SN light curve, i.e., fainter, quickly declining SNe Ia favor passive host galaxies, while brighter, slowly declining Ia's favor star-forming galaxies. We also find evidence (at between 2 to 3 sigma) that SNe Ia are ~0.1 magnitudes brighter in passive host galaxies, than in star-forming hosts, after the SN Ia light curves have been standardized using the light curve shape and color variations: This difference in brightness is present in both the SALT2 and MCLS2k2 light curve fitting methodologies. We see evidence for differences in the SN Ia color relationship between passive and star-forming host galaxies, e.g., for the MLCS2k2 technique, we see that SNe Ia in passive hosts favor a dust law of R_V ~1, while SNe Ia in star-forming hosts require R_V ... 11. Host Galaxies of Type Ia Supernovae from the Nearby Supernova Factory Childress, M J; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Chotard, N; Copin, Y; Fakhouri, H K; Gangler, E; Guy, J; Hsiao, E Y; Kerschhaggl, M; Kim, A G; Kowalski, M; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Runge, K; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A; Wu, C 2013-01-01 We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory (SNfactory). Combining GALEX UV data with optical and near infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star-formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high precision redshifts, gas-phase metallicities, and Halpha-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from SDSS for stellar masses log(M_*/M_Sun)>8.5 where the relation is well-defined. The star-formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, thou... 12. The Post-starburst Evolution of Tidal Disruption Event Host Galaxies French, K. Decker; Arcavi, Iair; Zabludoff, Ann 2017-02-01 We constrain the recent star formation histories of the host galaxies of eight optical/UV-detected tidal disruption events (TDEs). Six hosts had quick starbursts of absorption line spectrum, we uncover emission lines; at least five hosts have ionization sources inconsistent with star formation that instead may be related to circumnuclear gas, merger shocks, or post-AGB stars. 13. A Bayesian approach to multi-messenger astronomy: identification of gravitational-wave host galaxies Fan, XiLong [School of Physics and Electronics Information, Hubei University of Education, 430205 Wuhan (China); Messenger, Christopher; Heng, Ik Siong [SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ (United Kingdom) 2014-11-01 We present a general framework for incorporating astrophysical information into Bayesian parameter estimation techniques used by gravitational wave data analysis to facilitate multi-messenger astronomy. Since the progenitors of transient gravitational wave events, such as compact binary coalescences, are likely to be associated with a host galaxy, improvements to the source sky location estimates through the use of host galaxy information are explored. To demonstrate how host galaxy properties can be included, we simulate a population of compact binary coalescences and show that for ∼8.5% of simulations within 200 Mpc, the top 10 most likely galaxies account for a ∼50% of the total probability of hosting a gravitational wave source. The true gravitational wave source host galaxy is in the top 10 galaxy candidates ∼10% of the time. Furthermore, we show that by including host galaxy information, a better estimate of the inclination angle of a compact binary gravitational wave source can be obtained. We also demonstrate the flexibility of our method by incorporating the use of either the B or K band into our analysis. 14. The impact of AGN on their host galaxies Harrison, C M 2013-01-01 In these proceedings I briefly: (1) review the impact (or "feedback") that active galactic nuclei (AGN) are predicted to have on their host galaxies and larger scale environment, (2) review the observational evidence for or against these predictions and (3) present new results on ionised outflows in AGN. The observational support for the "maintenance mode" of feedback is strong (caveat the details); AGN at the centre of massive halos appear to be regulating the cooling of hot gas, which could in turn control the levels of future star formation (SF) and black hole growth. In contrast, direct observational support for more rapid forms of feedback, which dramatically impact on SF (i.e., the "quasar mode"), remains elusive. From a systematic study of the spectra of approx. 24000 z10^23 W/Hz). Follow-up IFU observations have shown that these extreme gas kinematics are extended over kilo-parsec scales. However, the co-existence of high-levels of SF, luminous AGN activity and radio jets raises interesting questions ... 15. Dust in High Redshift Gamma Ray Burst Host Galaxies Liang, Shunlin; Li, A. 2009-12-01 The discovery of high-redshift GRBs opens a new window into the nature of dust in the early universe. We explore the dust properties of the host galaxies of a large sample (32 objects) of long-GRBs at 2.0≤ z ≤ 6.7, with a mean redshift of z=3.34 (corresponding to a look-back time of 1.94 Gyr), by fitting their optical-near-IR afterglow spectra. The average dust extinction in the visual band is AV=0.3. The EB-V/NHI and AV/NHI ratios decrease linearly with the dust-to-gas ratio, suggesting that the dust properties remain unchanged at the epoch of 2.0≤ z ≤ 6.7. The inferred extinction curves are closely reproduced in terms of a mixture of amorphous silicate and graphite. The quanities of amorphous silicate and graphite (relative to H) both appear to decrease with, while their cut-off grain sizes show no significant evolution in the interval 2.0≤ z ≤ 6.7. 16. Superstellar clusters and their impact on their host galaxies Tenorio-Tagle, G; Muñoz-Tunón, C; Tenorio-Tagle, Guillermo; Silich, Sergiy; Munoz-Tunon, Casiana 2005-01-01 We review the properties of young superstellar clusters and the impact that their evolution has in their host galaxies. In particular we look at the two different star-forming feedback modes: positive and negative feedback. The development of strong isotropic winds emanating from massive clusters, capable of disrupting the remains of the parental cloud as well as causing the large-scale restructuring of the surrounding ISM, has usually been taken as a negative feedback agent. Here we show the impact that radiative cooling has on the resultant outflows and then, as an extreme example, we infer from the observations of M82 the detailed inner structure of supergalactic winds and define through numerical simulations the ingredients required to match such structures.We also show how when radiative cooling becomes significant within the star cluster volume itself (~ 30% of the deposited energy), the force of gravity takes over and drives in situ all the matter deposited by winds and supernovae into several generati... 17. Host Galaxy Properties of the Swift BAT Ultra Hard X-Ray Selected AGN Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa M.; Baumgartner, Wayne; Tueller, Jack; Gehrels, Neil; Valencic, Lynne 2011-01-01 We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) AGN with host galaxy optical data to date, with 185 nearby (zAGN from the Swift Burst Alert Telescope (BAT) sample. The BAT AGN host galaxies have intermediate optical colors (u -- r and g -- r) that are bluer than a comparison sample of inactive galaxies and optically selected AGN from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGN are mainly due to a higher fraction of mergers and massive spirals than in the comparison samples. BAT AGN in massive galaxies (log Stellar Mass >10.5) have a 5 to 10 times higher rate of spiral morphologies than in SDSS AGN or inactive galaxies. We also see enhanced far-IR emission in BAT AGN suggestive of higher levels of star formation compared to the comparison samples. BAT AGN are preferentially found in the most massive host galaxies with high concentration indexes indicative of large bulge-to-disk ratios and large supermassive black holes. The narrow-line (NL) BAT AGN have similar intrinsic luminosities as the SDSS NL Seyferts based on measurements of [O III] Lambda 5007. There is also a correlation between the stellar mass and X-ray emission. The BAT AGN in mergers have bluer colors and greater ultra hard X-ray emission compared to the BAT sample as whole. In agreement with the Unified Model of AGN, and the relatively unbiased nature of the BAT sources, the host galaxy colors and morphologies are independent of measures of obscuration such as X-ray column density or Seyfert type. The high fraction of massive spiral galaxies and galaxy mergers in BAT AGN suggest that host galaxy morphology is related to the activation and fueling of local AGN. 18. On the Origin of the Mass-Metallicity Relation for GRB Host Galaxies Kocevski, Daniel; /KIPAC, Menlo Park; West, Andrew A.; /Boston U., Dept. Astron. 2011-06-02 We investigate the nature of the mass-metallicity (M-Z) relation for long gamma-ray burst (LGRB) host galaxies. Recent studies suggest that the M-Z relation for local LGRB host galaxies may be systematically offset towards lower metallicities relative to the M-Z relation defined by the general star forming galaxy (SDSS) population. The nature of this offset is consistent with suggestions that low metallicity environments may be required to produce high mass progenitors, although the detection of several GRBs in high-mass, high-metallicity galaxies challenges the notion of a strict metallicity cut-off for host galaxies that are capable of producing GRBs. We show that the nature of this reported offset may be explained by a recently proposed anti-correlation between the star formation rate (SFR) and the metallicity of star forming galaxies. If low metallicity galaxies produce more stars than their equally massive, high-metallicity counterparts, then transient events that closely trace the SFR in a galaxy would be more likely to be found in these low metallicity, low mass galaxies. Therefore, the offset between the GRB and SDSS defined M-Z relations may be the result of the different methods used to select their respective galaxy populations, with GRBs being biased towards low metallicity, high SFR, galaxies. We predict that such an offset should not be expected of transient events that do not closely follow the star formation history of their host galaxies, such as short duration GRBs and SN Ia, but should be evident in core collapse SNe found through upcoming untargeted surveys. 19. X-Ray bright active galactic nuclei in massive galaxy clusters - II. The fraction of galaxies hosting active nuclei Ehlert, S.; von der Linden, A.; Allen, S. W. 2013-01-01 We present a measurement of the fraction of cluster galaxies hosting X-ray bright active galactic nuclei (AGN) as a function of clustercentric distance scaled in units of r500. Our analysis employs high-quality Chandra X-ray and Subaru optical imaging for 42 massive X-ray-selected galaxy cluster......, both of which are also suppressed near cluster centres to a comparable extent. These results strongly support the idea that X-ray AGN activity and strong star formation are linked through their common dependence on available reservoirs of cold gas....... fields spanning the redshift range 0.2 cluster galaxy AGN fraction in the central... 20. HOST GALAXY PROPERTIES AND HUBBLE RESIDUALS OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others 2013-06-20 We examine the relationship between Type Ia supernova (SN Ia) Hubble residuals and the properties of their host galaxies using a sample of 115 SNe Ia from the Nearby Supernova Factory. We use host galaxy stellar masses and specific star formation rates fitted from photometry for all hosts, as well as gas-phase metallicities for a subset of 69 star-forming (non-active galactic nucleus) hosts, to show that the SN Ia Hubble residuals correlate with each of these host properties. With these data we find new evidence for a correlation between SN Ia intrinsic color and host metallicity. When we combine our data with those of other published SN Ia surveys, we find the difference between mean SN Ia brightnesses in low- and high-mass hosts is 0.077 {+-} 0.014 mag. When viewed in narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus of Hubble residuals at high and low host masses with a rapid transition over a short mass range (9.8 {<=} log (M{sub *}/M{sub Sun }) {<=} 10.4). Although metallicity has been a favored interpretation for the origin of the Hubble residual trend with host mass, we illustrate how dust in star-forming galaxies and mean SN Ia progenitor age both evolve along the galaxy mass sequence, thereby presenting equally viable explanations for some or all of the observed SN Ia host bias. 1. Gamma-ray Bursts: Radio Afterglow and Host Galaxy Study with The FAST Telescope Li, L. B.; Huang, Y. F.; Kong, S. W.; Zhang, Z. B.; Li, D.; Luo, J. J. 2016-02-01 For four types of GRBs, namely high-luminosity, low-luminosity, standard and failed GRBs, we calculated their radio afterglow light curves. Meanwhile, considering contributions from host galaxies in radio bands, we statistically investigated the effect of hosts on radio afterglows. It is found that a tight anti-correlation exists between the ratio of radio flux (RRF) of host galaxy to the total radio afterglow peak flux and the observed frequency. Using this method, the host flux densities of those bursts without host measurements can be estimated at low or medium frequencies. We predicted that almost all types of radio afterglows, except that of low-luminosity GRBs, can be observed by FAST up to z = 15 or even more. FAST is expected to significantly expand the samples of GRB radio afterglows and host galaxies. 2. Host galaxies of long gamma-ray bursts in the Millennium Simulation Chisari, N. E.; Tissera, P. B.; Pellizza, L. J. 2010-10-01 In this work, we investigate the nature of the host galaxies of long gamma-ray bursts (LGRBs) using a galaxy catalogue constructed from the Millennium Simulation. We developed an LGRB synthetic model based on the hypothesis that these events originate at the end of the life of massive stars following the collapsar model, with the possibility of including a constraint on the metallicity of the progenitor star. A complete observability pipeline was designed to calculate a probability estimation for a galaxy to be observationally identified as a host for LGRBs detected by present observational facilities. This new tool allows us to build an observable host galaxy catalogue which is required to reproduce the current stellar mass distribution of observed hosts. This observability pipeline predicts that the minimum mass for the progenitor stars should be ~ 75 Msolar in order to be able to reproduce BATSE observations. Systems in our observable catalogue are able to reproduce the observed properties of host galaxies, namely stellar masses, colours, luminosity, star formation activity and metallicities as a function of redshift. At z > 2, our model predicts that the observable host galaxies would be very similar to the global galaxy population. We found that ~ 88 per cent of the observable host galaxies with mean gas metallicity lower than 0.6 Zsolar have stellar masses in the range 108.5-1010.3 Msolar, in excellent agreement with observations. Interestingly in our model, observable host galaxies remain mainly within this mass range regardless of redshift, since lower stellar mass systems would have a low probability of being observed while more massive ones would be too metal-rich. Observable host galaxies are predicted to preferentially inhabit dark matter haloes in the range 1011-1011.5 Msolar, with a weak dependence on redshift. They are also found to preferentially map different density environments at different stages of evolution of the Universe. At high redshifts 3. The Host Galaxies of Type Ia Supernovae Discovered by the Palomar Transient Factory Pan, Y.-C.; Sullivan, M.; McGuire, K.; Hook, I. M.; Nugent, P. E.; Howell, D. A.; Arcavi, I.; Botyanszki, J.; Cenko, Stephen Bradley; DeRose, J. 2013-01-01 We present spectroscopic observations of the host galaxies of 82 low-redshift type Ia supernovae (SNe Ia) discovered by the Palomar Transient Factory (PTF). We determine star-formation rates, gas-phase stellar metallicities, and stellar masses and ages of these objects. As expected, strong correlations between the SN Ia light-curve width (stretch) and the host age mass metallicity are found: fainter, faster-declining events tend to be hosted by older massive metal-rich galaxies. There is some evidence that redder SNe Ia explode in higher metallicity galaxies, but we found no relation between the SN colour and host galaxy extinction based on the Balmer decrement, suggesting that the colour variation of these SNe does not primarily arise from this source. SNe Ia in higher-mass metallicity galaxies also appear brighter after stretch colour corrections than their counterparts in lower mass hosts, and the stronger correlation is with gas-phase metallicity suggesting this may be the more important variable. We also compared the host stellar mass distribution to that in galaxy targeted SN surveys and the high-redshift untargeted Supernova Legacy Survey (SNLS). SNLS has many more low mass galaxies, while the targeted searches have fewer. This can be explained by an evolution in the galaxy stellar mass function, coupled with a SN delay-time distribution proportional to t1. Finally, we found no significant difference in the mass--metallicity relation of our SN Ia hosts compared to field galaxies, suggesting any metallicity effect on the SN Ia rate is small. 4. Spatially-resolved dust properties of the GRB 980425 host galaxy Michałowski, Michał J.; Hunt, L. K.; Palazzi, E. 2014-01-01 ), located 800 pc away from the GRB position. The host is characterised by low dust content and high fraction of UV-visible star-formation, similar to other dwarf galaxies. Such galaxies are abundant in the local universe, so it is not surprising to find a GRB in one of them, assuming the correspondence... 5. The MOSDEF survey: AGN multi-wavelength identification, selection biases and host galaxy properties Azadi, Mojegan; Aird, James; Reddy, Naveen; Shapley, Alice; Freeman, William R; Kriek, Mariska; Leung, Gene C K; Mobasher, Bahram; Price, Sedona H; Sanders, Ryan L; Shivaei, Irene; Siana, Brian 2016-01-01 We present results from the MOSFIRE Deep Evolution Field (MOSDEF) survey on the identification, selection biases and host galaxy properties of 55 X-ray, IR and optically-selected active galactic nuclei (AGN) at$1.4 < z < 3.8$. We obtain rest-frame optical spectra of galaxies and AGN and use the BPT diagram to identify optical AGN. We examine the uniqueness and overlap of the AGN identified at different wavelengths. There is a strong bias against identifying AGN at any wavelength in low mass galaxies, and an additional bias against identifying IR AGN in the most massive galaxies. AGN host galaxies span a wide range of star formation rate (SFR), similar to inactive galaxies once stellar mass selection effects are accounted for. However, we generally identify IR AGN in less dusty galaxies with relatively higher SFR and optical AGN in dusty galaxies with relatively lower SFR. X-ray AGN selection does not display a bias with host galaxy SFR. These results are consistent with those from larger studies at low... 6. Host galaxies of luminous quasars: population synthesis of optical off-axis spectra Wold, I; Wolf, M J; Hooper, E J 2010-01-01 There is increasing evidence of a connection between AGN activity and galaxy evolution. To obtain further insight into this potentially important evolutionary phase, we analyse the properties of quasar host galaxies. In this paper, we present a population synthesis modeling technique for off-axis spectra, the results of which constrain host colour and the stellar ages of luminous quasars (M_V(nuc) 10^40 erg s^-1) quasars to be located in redder host galaxies in comparison to th eir less luminous radio counterparts. While the host colour and age of our radio luminous sample is in close proximity to the green valley, our radio faint sample is consistent with quiescent star-forming galaxies. However, further observations are needed to confirm these results. Finally, we discuss future applications for our technique on a larger sample of objects being obtained via SALT and WIYN telescope observing campaigns. 7. The afterglow and the host galaxy of GRB 011211 Jakobsson, P.; Hjorth, J.; Fynbo, J. P. U.; Gorosabel, J.; Pedersen, K.; Burud, I.; Levan, A.; Kouveliotou, C.; Tanvir, N.; Fruchter, A.; Rhoads, J.; Grav, T.; Hansen, M. W.; Michelsen, R.; Andersen, M. I.; Jensen, B. L.; Pedersen, H.; Thomsen, B.; Weidinger, M.; Bhargavi, S. G.; Cowsik, R.; Pandey, S. B. 2003-09-01 We present optical, near-infrared, and X-ray observations of the optical afterglow (OA) of the X-ray rich, long-duration gamma-ray burst GRB 011211. Hubble Space Telescope (HST) data obtained 14, 26, 32, and 59 days after the burst, show the host galaxy to have a morphology that is fairly typical of blue galaxies at high redshift. We measure its magnitude to be R = 24.95 +/- 0.11. We detect a break in the OA R-band light curve which is naturally accounted for by a collimated outflow geometry. By fitting a broken power-law to the data we find a best fit with a break 1.56 +/- 0.02 days after the burst, a pre-break slope of alpha1 = -0.95 +/- 0.02, and a post-break slope of alpha2 = -2.11 +/- 0.07. The UV-optical spectral energy distribution (SED) around 14 hours after the burst is best fit with a power-law with index beta = -0.56 +/- 0.19 reddened by an SMC-like extinction law with a modest AV = 0.08 +/- 0.08 mag. By comparison, from the XMM-Newton X-ray data at around the same time, we find a decay index of alphaX = -1.62 +/- 0.36 and a spectral index of betaX = -1.21+0.10-0.15. Interpolating between the UV-optical and X-ray implies that the cooling frequency is located close to ~ 1016 Hz in the observer frame at the time of the observations. We argue, using the various temporal and spectral indices above, that the most likely afterglow model is that of a jet expanding into an external environment that has a constant mean density rather than a wind-fed density structure. We estimate the electron energy index for this burst to be p ~ 2.3. Based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden. Based on observations made with ESO Telescopes at the Paranal Observatory by GRACE under programme ID 69.D-0701. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the 8. H0LiCOW. VI. Testing the fidelity of lensed quasar host galaxy reconstruction Ding, Xuheng; Liao, Kai; Treu, Tommaso; Suyu, Sherry H.; Chen, Geoff C.-F.; Auger, Matthew W.; Marshall, Philip J.; Agnello, Adriano; Courbin, Frederic; Nierenberg, Anna M.; Rusu, Cristian E.; Sluse, Dominique; Sonnenfeld, Alessandro; Wong, Kenneth C. 2017-03-01 The empirical correlation between the mass of a supermassive black hole (M_BH) and its host galaxy properties is widely considered to be an evidence of their co-evolution. A powerful way to test the co-evolution scenario and learn about the feedback processes linking galaxies and nuclear activity is to measure these correlations as a function of redshift. Unfortunately, currently M_BH can only be estimated in active galaxies at cosmological distances. At these distances, bright active galactic nuclei (AGNs) can outshine the host galaxy, making it extremely difficult to measure the host's luminosity. Strongly lensed AGNs provide in principle a great opportunity to improve the sensitivity and accuracy of the host galaxy luminosity measurements as the host galaxy is magnified and more easily separated from the point source, provided the lens model is sufficiently accurate. In order to measure the M_BH-L correlation with strong lensing, it is necessary to ensure that the lens modelling is accurate, and that the host galaxy luminosity can be recovered to at least a precision and accuracy better than that of the typical M_BH measurement. We carry out extensive and realistic simulations of deep Hubble Space Telescope observations of lensed AGNs obtained by our collaboration. We show that the host galaxy luminosity can be recovered with better accuracy and precision than the typical uncertainty in M_BH(∼0.5 dex) for hosts as faint as 2-4 mag dimmer than the AGN itself. Our simulations will be used to estimate bias and uncertainties in the actual measurements to be presented in a future paper. 9. Supernovae and their host galaxies - IV. The distribution of supernovae relative to spiral arms Aramyan, L S; Petrosian, A R; de Lapparent, V; Bertin, E; Mamon, G A; Kunth, D; Nazaryan, T A; Adibekyan, V; Turatto, M 2016-01-01 Using a sample of 215 supernovae (SNe), we analyze their positions relative to the spiral arms of their host galaxies, distinguishing grand-design (GD) spirals from non-GD (NGD) galaxies. We find that: (1) in GD galaxies, an offset exists between the positions of Ia and core-collapse (CC) SNe relative to the peaks of arms, while in NGD galaxies the positions show no such shifts; (2) in GD galaxies, the positions of CC SNe relative to the peaks of arms are correlated with the radial distance from the galaxy nucleus. Inside (outside) the corotation radius, CC SNe are found closer to the inner (outer) edge. No such correlation is observed for SNe in NGD galaxies nor for SNe Ia in either galaxy class; (3) in GD galaxies, SNe Ibc occur closer to the leading edges of the arms than do SNe II, while in NGD galaxies they are more concentrated towards the peaks of arms. In both samples of hosts, the distributions of SNe Ia relative to the arms have broader wings. These observations suggest that shocks in spiral arms of... 10. H0LiCOW VI. Testing the fidelity of lensed quasar host galaxy reconstruction Ding, Xuheng; Treu, Tommaso; Suyu, Sherry H; Chen, Geoff C -F; Auger, Matthew W; Marshall, Philip J; Agnello, Adriano; Courbin, Frederic; Nierenberg, Anna M; Rusu, Cristian E; Sluse, Dominique; Sonnenfeld, Alessandro; Wong, Kenneth C 2016-01-01 The empirical correlation between the mass of a super-massive black hole (MBH) and its host galaxy properties is widely considered to be evidence of their co-evolution. A powerful way to test the co-evolution scenario and learn about the feedback processes linking galaxies and nuclear activity is to measure these correlations as a function of redshift. Unfortunately, currently MBH can only be estimated in active galaxies at cosmological distances. At these distances, bright active galactic nuclei (AGN) can outshine the host galaxy, making it extremely difficult to measure the host's luminosity. Strongly lensed AGNs provide in principle a great opportunity to improve the sensitivity and accuracy of the host galaxy luminosity measurements as the host galaxy is magnified and more easily separated from the point source, provided the lens model is sufficiently accurate. In order to measure the MBH-L correlation with strong lensing, it is necessary to ensure that the lens modelling is accurate, and that the host ga... 11. Early-type Host Galaxies of Type Ia Supernovae. I. Evidence for Downsizing Kang, Yijung; Lim, Dongwook; Chung, Chul; Lee, Young-Wook 2016-01-01 Type Ia supernova (SN Ia) cosmology provides the most direct evidence for the presence of dark energy. This result is based on the assumption that the look-back time evolution of SN Ia luminosity, after light-curve corrections, would be negligible. Recent studies show, however, that the Hubble residual (HR) of SN Ia is correlated with the mass and morphology of host galaxies, implying the possible dependence of SN Ia luminosity on host galaxy properties. In order to investigate this more directly, we have initiated spectroscopic survey for the early-type host galaxies, for which population age and metallicity can be more reliably determined from the absorption lines. As the first paper of the series, here we present the results from high signal-to-noise ratio (>100 per pixel) spectra for 27 nearby host galaxies in the southern hemisphere. For the first time in host galaxy studies, we find a significant (~3.9sigma) correlation between host galaxy mass (velocity dispersion) and population age, which is consiste... 12. STAR CLUSTER COMPLEXES AND THE HOST GALAXY IN THREE H II GALAXIES: Mrk 36, UM 408, AND UM 461 Lagos, P. [Centro de Astrofisica da Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal); Telles, E. [Observatorio Nacional, Rua Jose Cristino, 77, Rio de Janeiro 20921-400 (Brazil); Nigoche-Netro, A. [Instituto de Astrofisica de Andalucia (IAA), Glorieta de la Astronomia s/n, 18008 Granada (Spain); Carrasco, E. R., E-mail: [email protected], E-mail: [email protected], E-mail: [email protected], E-mail: [email protected] [Gemini Observatory/AURA, Southern Operations Center, Casilla 603, La Serena (Chile) 2011-11-15 We present a stellar population study of three H II galaxies (Mrk 36, UM 408, and UM 461) based on the analysis of new ground-based high-resolution near-infrared J, H, and K{sub p} broadband and Br{gamma} narrowband images obtained with Gemini/NIRI. We identify and determine the relative ages and masses of the elementary star clusters and/or star cluster complexes of the starburst regions in each of these galaxies by comparing the colors with evolutionary synthesis models that include the contribution of stellar continuum, nebular continuum, and emission lines. We found that the current star cluster formation efficiency in our sample of low-luminosity H II galaxies is {approx}10%. Therefore, most of the recent star formation is not in massive clusters. Our findings seem to indicate that the star formation mode in our sample of galaxies is clumpy, and that these complexes are formed by a few massive star clusters with masses {approx}>10{sup 4} M{sub Sun }. The age distribution of these star cluster complexes shows that the current burst started recently and likely simultaneously over short timescales in their host galaxies, triggered by some internal mechanism. Finally, the fraction of the total cluster mass with respect to the low surface brightness (or host galaxy) mass, considering our complete range in ages, is less than 1%. 13. Rapidly growing black holes and host galaxies in the distant Universe from the Herschel Radio Galaxy Evolution Project Drouart, G; Vernet, J; Seymour, N; Lehnert, M; Barthel, P; Bauer, F E; Ibar, E; Galametz, A; Haas, M; Hatch, N; Mullaney, J R; Nesvadba, N; Rocca-Volmerange, B; Rottgering, H J A; Stern, D; Wylezalek, D 2014-01-01 We present results from a survey of 70 radio galaxies (RGs) at redshifts 12.5 are higher than the sSFR of typical star-forming galaxies over the same redshift range but are similar or perhaps lower than the galaxy population for RGs at z<2.5. By comparing the sSFR and the specific black hole mass accretion rate, we conclude that BHs in radio loud AGN are already, or soon will be, overly massive compared to their host galaxies in terms of expectations from the local MBH-MGal relation. In order to catch up'' with the BH, the galaxies require about an order-of magnitude more time to grow in mass, at the observed SFRs, compared to the time the BH is actively accreting. However, during the current cycle of activity, we argue that this catching-up is likely to be difficult due to the short gas depletion times. Finally, we speculate on how the host galaxies might grow sufficiently in stellar mass to ultimately fall onto the local MBH-MGal relation. 14. The HST Survey of BL~Lacertae Objects. IV. Infrared Imaging of Host Galaxies Scarpa, R; Padovani, P; O'Dowd, M; Scarpa, Riccardo; Padovani, Paolo; O'Dowd, Matthew; Calzetti, Daniela 2000-01-01 The HST NICMOS Camera 2 was used for H-band imaging of 12 BL Lacertae objects taken from the larger sample observed with the WFPC2 in the R band (Urry et al. 2000; Scarpa et al. 2000). Ten of the 12 BL Lacs are clearly resolved, and the detected host galaxies are large, bright ellipticals with average H-band absolute magnitude M=-26.2+-0.45 mag and effective radius 10+-5 kpc. The rest-frame integrated color of the host galaxies is on average R-H=2.3+-0.3, consistent with the value for both radio galaxies and normal, non-active elliptical galaxies, and indicating the dominant stellar population is old. The host galaxies tend to be bluer in their outer regions than in their cores, with average color gradient Delta(R-H)/Delta(log r)=-0.2 mag, again consistent with results for normal non-active elliptical galaxies. The infrared Kormendy relation, derived for the first time for BL Lac host galaxies, is m(e) = 3.8*log(R)+14.8 (where m(e) is the surface brightness at the effective radius R), fully in agreement with ... 15. Do Nuclear Star Clusters and Black Holes Follow the Same Host-Galaxy Correlations? Erwin, Peter 2011-01-01 Studies have suggested that there is a strong correlation between the masses of nuclear star clusters (NSCs) and their host galaxies, a correlation which said to be an extension of the well-known correlations between supermassive black holes (SMBHs) and their host galaxies. But careful analysis of disk galaxies -- including 2D bulge/disk/bar decompositions -- shows that while SMBHs correlate with the stellar mass of the bulge component of galaxies, the masses of NSCs correlate much better with the total galaxy stellar mass. In addition, the mass ratio M_nsc/M_star,tot for NSCs in spirals (at least those with Hubble types Sc and later) is typically an order of magnitude smaller than the mass ratio M_bh/M_star, bulge of SMBHs. The absence of a universal "central massive object" correlation argues against common formation and growth mechanisms for both SMBHs and NSCs. We also discuss evidence for a break in the NSC-host galaxy correlation: galaxies with Hubble types earlier than Sbc appear to host systematically... 16. Improving Type Ia Supernova Standard Candle Cosmology Measurements Using Observations of Early-Type Host Galaxies Meyers, Joshua Evan Type Ia supernovae (SNe Ia) are the current standard-bearers for dark energy but face several hurdles for their continued success in future large surveys. For example, spectroscopic classification of the myriad SNe soon to be discovered will not be possible, and systematics from uncertainties in dust corrections and the evolution of SN demographics and/or empirical calibrations used to standardize SNe Ia must be studied. Through the identification of low-dust host galaxies and through increased understanding of both the SN - progenitor connections and empirical calibrations, host galaxy information may offer opportunities to improve the cosmological utility of SNe Ia. The first half of this thesis analyzes the sample of SNe Ia discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields. Correlations between properties of SNe and their host galaxies are examined at high redshift. Using galaxy color and quantitative morphology to determine the red sequence in 25 clusters, a model is developed to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, 6 early-type cluster member hosts and 11 SN Ia early-type field hosts are identified. For the first time at z > 0.9, the correlation between host galaxy type and the rise and fall time of SN Ia light curves is confirmed. The relatively simple spectral energy distributions of early-type galaxies also enables stellar mass measurements for these hosts. In combination with literature host mass measurements, these measurements are used to show, at z > 0.9, a hint of the correlation between host mass and Hubble residuals reported at lower redshift. By simultaneously fitting cluster galaxy formation histories and dust content to the scatter of the cluster red sequences, it is shown that dust reddening of early-type cluster SN hosts is likely less 17. An Efficient Approach to Obtaining Large Numbers of Distant Supernova Host Galaxy Redshifts Lidman, C; Sullivan, M; Myzska, J; Dobbie, P; Glazebrook, K; Mould, J; Astier, P; Balland, C; Betoule, M; Carlberg, R; Conley, A; Fouchez, D; Guy, J; Hardin, D; Hook, I; Howell, D A; Pain, R; Palanque-Delabrouille, N; Perrett, K; Pritchet, C; Regnault, N; Rich, J 2012-01-01 We use the wide-field capabilities of the 2dF fibre positioner and the AAOmega spectrograph on the Anglo-Australian Telescope (AAT) to obtain redshifts of galaxies that hosted supernovae during the first three years of the Supernova Legacy Survey (SNLS). With exposure times ranging from 10 to 60 ksec per galaxy, we were able to obtain redshifts for 400 host galaxies in two SNLS fields, thereby substantially increasing the total number of SNLS supernovae with host galaxy redshifts. The median redshift of the galaxies in our sample that hosted photometrically classified Type Ia supernovae (SNe Ia) is 0.77, which is 25% higher than the median redshift of spectroscopically confirmed SNe Ia in the three-year sample of the SNLS. Our results demonstrate that one can use wide-field fibre-fed multi-object spectrographs on 4m telescopes to efficiently obtain redshifts for large numbers of supernova host galaxies over the large areas of sky that will be covered by future high-redshift supernova surveys, such as the Dark... 18. AGN host galaxy mass function in COSMOS. Is AGN feedback responsible for the mass-quenching of galaxies? Bongiorno, A.; Schulze, A.; Merloni, A.; Zamorani, G.; Ilbert, O.; La Franca, F.; Peng, Y.; Piconcelli, E.; Mainieri, V.; Silverman, J. D.; Brusa, M.; Fiore, F.; Salvato, M.; Scoville, N. 2016-04-01 We investigate the role of supermassive black holes in the global context of galaxy evolution by measuring the host galaxy stellar mass function (HGMF) and the specific accretion rate, that is, λSAR, the distribution function (SARDF), up to z ~ 2.5 with ~1000 X-ray selected AGN from XMM-COSMOS. Using a maximum likelihood approach, we jointly fit the stellar mass function and specific accretion rate distribution function, with the X-ray luminosity function as an additional constraint. Our best-fit model characterizes the SARDF as a double power-law with mass-dependent but redshift-independent break, whose low λSAR slope flattens with increasing redshift while the normalization increases. This implies that for a given stellar mass, higher λSAR objects have a peak in their space density at earlier epoch than the lower λSAR objects, following and mimicking the well-known AGN cosmic downsizing as observed in the AGN luminosity function. The mass function of active galaxies is described by a Schechter function with an almost constant M∗⋆ and a low-mass slope α that flattens with redshift. Compared to the stellar mass function, we find that the HGMF has a similar shape and that up to log (M⋆/M⊙) ~ 11.5, the ratio of AGN host galaxies to star-forming galaxies is basically constant (~10%). Finally, the comparison of the AGN HGMF for different luminosity and specific accretion rate subclasses with a previously published phenomenological model prediction for the "transient" population, which are galaxies in the process of being mass-quenched, reveals that low-luminosity AGN do not appear to be able to contribute significantly to the quenching and that at least at high masses, that is, M⋆ > 1010.7 M⊙, feedback from luminous AGN (log Lbol ≳ 46 [erg/s]) may be responsible for the quenching of star formation in the host galaxy. 19. Decreased specific star formation rates in AGN host galaxies Shimizu, T. Taro; Mushotzky, Richard F.; Meléndez, Marcio; Koss, Michael; Rosario, David J. 2015-09-01 We investigate the location of an ultra-hard X-ray selected sample of active galactic nuclei (AGN) from the Swift Burst Alert Telescope (BAT) catalogue with respect to the main sequence (MS) of star-forming galaxies using Herschel-based measurements of the star formation rate (SFR) and M*'s from Sloan Digital Sky Survey photometry where the AGN contribution has been carefully removed. We construct the MS with galaxies from the Herschel Reference Survey and Herschel Stripe 82 Survey using the exact same methods to measure the SFR and M* as the Swift/BAT AGN. We find that a large fraction of the Swift/BAT AGN lie below the MS indicating decreased specific SFR (sSFR) compared to non-AGN galaxies. The Swift/BAT AGN are then compared to a high-mass galaxy sample (CO Legacy Database for GALEX Arecibo SDSS Survey, COLD GASS), where we find a similarity between the AGN in COLD GASS and the Swift/BAT AGN. Both samples of AGN lie firmly between star-forming galaxies on the MS and quiescent galaxies far below the MS. However, we find no relationship between the X-ray luminosity and distance from the MS. While the morphological distribution of the BAT AGN is more similar to star-forming galaxies, the sSFR of each morphology is more similar to the COLD GASS AGN. The merger fraction in the BAT AGN is much higher than the COLD GASS AGN and star-forming galaxies and is related to distance from the MS. These results support a model in which bright AGN tend to be in high-mass star-forming galaxies in the process of quenching which eventually starves the supermassive black hole itself. 20. Hubble Residuals of Nearby SN Ia Are Correlated with Host Galaxy Masses Kelly, Patrick L.; /KIPAC, Menlo Park /SLAC; Hicken, Malcolm; /Harvard-Smithsonian Ctr. Astrophys.; Burke, David L.; /KIPAC, Menlo Park /SLAC; Mandel, Kaisey S.; Kirshner, Robert P.; /Harvard-Smithsonian Ctr. Astrophys. 2010-05-03 From Sloan Digital Sky Survey u{prime} g{prime} r{prime} i{prime} z{prime} imaging, we estimate the stellar masses of the host galaxies of 70 low redshift SN Ia (0.015 < z < 0.08) from the hosts absolute luminosities and mass-to-light ratios. These nearby SN were discovered largely by searches targeting luminous galaxies, and we find that their host galaxies are substantially more massive than the hosts of SN discovered by the flux-limited Supernova Legacy Survey. Testing four separate light curve fitters, we detect {approx}2.5{sigma} correlations of Hubble residuals with both host galaxy size and stellar mass, such that SN Ia occurring in physically larger, more massive hosts are {approx}10% brighter after light curve correction. The Hubble residual is the deviation of the inferred distance modulus to the SN, calculated from its apparent luminosity and light curve properties, away from the expected value at the SN redshift. Marginalizing over linear trends in Hubble residuals with light curve parameters shows that the correlations cannot be attributed to a light curve-dependent calibration error. Combining 180 higher-redshift ESSENCE, SNLS, and HigherZ SN with 30 nearby SN whose host masses are less than 10{sup 10.8} M{circle_dot} n a cosmology fit yields 1 + w = 0.22{sub -0.108}{sup +0.152}, while a combination where the 30 nearby SN instead have host masses greater than 10{sup 10.8} M{circle_dot} yields 1 + w = ?0.03{sub -0.143}{sup +0.217}. Progenitor metallicity, stellar population age, and dust extinction correlate with galaxy mass and may be responsible for these systematic effects. Host galaxy measurements will yield improved distances to SN Ia. 1. AGN host galaxies at redshift z~0.7: peculiar or not? Boehm, Asmus; Bell, Eric F; Jahnke, Knud; Wolf, Christian; Bacon, David; Barden, Marco; Gray, Meghan E; Hoeppe, Goetz; Jogee, Sharda; McIntosh, Dan H; Peng, Chien Y; Robaina, Adai R; Balogh, Michael; Barazza, Fabio D; Caldwell, John A R; Heymans, Catherine; Haeussler, Boris; van Kampen, Eelco; Lane, Kyle; Meisenheimer, Klaus; Sanchez, Sebastian F; Taylor, Andy N; Zheng, Xianzhong 2012-01-01 We perform a quantitative morphological comparison between the hosts of Active Galactic Nuclei (AGN) and quiescent galaxies at intermediate redshifts (z~0.7). The imaging data are taken from the large HST/ACS mosaics of the GEMS and STAGES surveys. Our main aim is to test whether nuclear activity at this cosmic epoch is triggered by major mergers. Using images of quiescent galaxies and stars, we create synthetic AGN images to investigate the impact of an optical nucleus on the morphological analysis of AGN hosts. Galaxy morphologies are parameterized using the asymmetry index A, concentration index C, Gini coefficient G and M20 index. A sample of ~200 synthetic AGN is matched to 21 real AGN in terms of redshift, host brightness and host-to-nucleus ratio to ensure a reliable comparison between active and quiescent galaxies. The optical nuclei strongly affect the morphological parameters of the underlying host galaxy. Taking these effects into account, we find that the morphologies of the AGN hosts are clearly ... 2. The physical properties of AGN host galaxies as a probe of SMBH feeding mechanisms Gatti, M; Menci, N; Bongiorno, A; Fiore, F 2014-01-01 Using a state-of-the-art semi analytic model (SAM) for galaxy formation, we have investigated the statistical effects of assuming two different mechanisms for triggering AGN activity on the properties of AGN host galaxies. We have considered a first accretion mode where AGN activity is triggered by disk instabilities (DI) in isolated galaxies, and a second feeding mode where such an activity is triggered by galaxy mergers and fly-by events (interactions, IT). We obtained the following results:i) for hosts with$M_* \\lesssim 10^{11} M_{\\bigodot}$, both DI and IT modes are able to account for the observed AGN hosts stellar mass function; for more massive hosts, the DI scenario predicts a lower space density than the IT model, lying below the observational estimates for z>0.8.ii) The analysis of the color-magnitude diagram (CMD) of AGN hosts for redshift z < 1.5 can provide a good observational test to effectively discriminate between the DI and IT mode, since DIs are expected to yield AGN host galaxy colors ... 3. The Sloan Digital Sky Survey Reverberation Mapping Project: Post-Starburst Signatures in Quasar Host Galaxies at z < 1 Matsuoka, Yoshiki; Shen, Yue; Brandt, William N; Greene, Jenny E; Ho, Luis C; Schneider, Donald P; Sun, Mouyuan; Trump, Jonathan R 2015-01-01 Quasar host galaxies are key for understanding the relation between galaxies and the supermassive black holes (SMBHs) at their cores. We present a study of 191 unobscured quasars and their host galaxies at z < 1, using high signal-to-noise ratio (SNR) spectra produced by the Sloan Digital Sky Survey Reverberation Mapping project. Clear detection of stellar absorption lines allows a reliable decomposition of the observed spectra into nuclear and host components, using spectral models of quasar and stellar radiations as well as emission lines from the interstellar medium. We estimate age, mass (M*), and velocity dispersion (sigma*) of the host stars, the star formation rate (SFR), quasar luminosity, and SMBH mass (Mbh), for each object. The quasars are preferentially hosted by massive galaxies with M* ~ 10^{11} Msun characterized by stellar ages around a billion years, which coincides with the transition phase of normal galaxies from the blue cloud to the red sequence. The host galaxies have relatively low S... 4. Decreased Specific Star Formation Rates in AGN Host Galaxies Shimizu, T Taro; Melendez, Marcio; Koss, Michael; Rosario, David 2015-01-01 We investigate the location of an ultra-hard X-ray selected sample of AGN from the Swift Burst Alert Telescope (BAT) catalog with respect to the main sequence (MS) of star-forming galaxies using Herschel-based measurements of the star formation rate (SFR) and stellar mass (\\mstar) from Sloan Digital Sky Survey (SDSS) photometry where the AGN contribution has been carefully removed. We construct the MS with galaxies from the Herschel Reference Survey and Herschel Stripe 82 Survey using the exact same methods to measure the SFR and \\mstar{} as the Swift/BAT AGN. We find a large fraction of the Swift/BAT AGN lie below the MS indicating decreased specific SFR (sSFR) compared to non-AGN galaxies. The Swift/BAT AGN are then compared to a high-mass galaxy sample (COLD GASS), where we find a similarity between the AGN in COLD GASS and the Swift/BAT AGN. Both samples of AGN lie firmly between star-forming galaxies on the MS and quiescent galaxies far below the MS. However, we find no relationship between the X-ray lum... 5. The Relation between Luminous AGNs and Star Formation in Their Host Galaxies Xu, Lei; Rieke, G. H.; Egami, E.; Haines, C. P.; Pereira, M. J.; Smith, G. P. 2015-08-01 We study the relation of active galactic nuclei (AGNs) to star formation in their host galaxies. Our sample includes 205 Type-1 and 85 Type-2 AGNs, 162 detected with Herschel, from fields surrounding 30 galaxy clusters in the Local Cluster Substructure Survey. The sample is identified by optical line widths and ratios after selection to be brighter than 1 mJy at 24 μm. We show that Type-2 AGN [O iii]λ5007 line fluxes at high z can be contaminated by their host galaxies with typical spectrograph entrance apertures (but our sample is not compromised in this way). We use spectral energy distribution (SED) templates to decompose the galaxy SEDs and estimate star formation rates (SFRs), AGN luminosities, and host galaxy stellar masses (described in an accompanying paper). The AGNs arise from massive black holes (˜ 3× {10}8{M}⊙ ) accreting at ˜10% of the Eddington rate and residing in galaxies with stellar mass \\gt 3× {10}10{M}⊙ ; those detected with Herschel have IR luminosity from star formation in the range of {L}{SF,{IR}}˜ {10}10-{10}12{L}⊙ . We find that (1) the specific SFRs in the host galaxies are generally consistent with those of normal star-forming (main sequence) galaxies; (2) there is a strong correlation between the luminosities from star formation and the AGN; and (3) the correlation may not result from a causal connection, but could arise because the black hole mass (and hence AGN Eddington luminosity) and star formation are both correlated with the galaxy mass. 6. Do Nuclear Star Clusters and Supermassive Black Holes Follow the Same Host-Galaxy Correlations? Peter Erwin 2012-01-01 Full Text Available Studies have suggested that there is a strong correlation between the masses of nuclear star clusters (NSCs and their host galaxies, a correlation which is said to be an extension of the well-known correlations between supermassive black holes (SMBHs and their host galaxies. But careful analysis of disk galaxies—including 2D bulge/disk/bar decompositions—shows that while SMBHs correlate with the stellar mass of the bulge component of galaxies, the masses of NSCs correlate much better with the total galaxy stellar mass. In addition, the mass ratio MNSC/M⋆, tot for NSCs in spirals (at least those with Hubble types Sc and later is typically an order of magnitude smaller than the mass ratio MBH/M⋆, bul of SMBHs. The absence of a universal “central massive object” correlation argues against common formation and growth mechanisms for both SMBHs and NSCs. We also discuss evidence for a break in the NSC-host galaxy correlation, galaxies with Hubble types earlier than Sbc appear to host systematically more massive NSCs than do types Sc and later. 7. A statistical study of H i gas in nearby narrow-line AGN-hosting galaxies Zhu, Yi-Nan; Wu, Hong, E-mail: [email protected], E-mail: [email protected] [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China) 2015-01-01 As a quenching mechanism, active galactic nucleus (AGN) feedback could suppress on going star formation in host galaxies. On the basis of a sample of galaxies selected from the Arecibo Legacy Fast ALFA (ALFALFA) H i survey, the dependence of the H i mass (M{sub H} {sub i}), stellar mass (M{sub *}), and H i-to-stellar mass ratio (M{sub H} {sub i}/M{sub *}) on various tracers of AGN activity are presented and analyzed in this paper. Almost all the AGN hostings in this sample are gas-rich galaxies, and there is not any evidence to indicate that the AGN activity could increase or decrease either M{sub H} {sub i} or M{sub H} {sub i}/M{sub *}. The position of the cold neutral gas cannot be fixed accurately based only on available H i data, due to the large beam size of ALFALFA survey. In addition, even though AGN hostings are more easily detected by an H i survey compared with absorption line galaxies, these two types of galaxies show similar star formation history. If an AGN hosting would ultimately evolve into an old red galaxy with low cold gas, then when and how the gas has been exhausted must be solved by future hypotheses and observations. 8. The host galaxy of GRB 011121: Morphology and Spectral Energy Distribution Yoldas, A K; Greiner, J; Pierini, D; Pian, E; Rau, A; Yoldas, Aybuke Kupcu; Salvato, Mara; Greiner, Jochen; Pierini, Daniele; Pian, Elena; Rau, Arne 2006-01-01 (Abridged) We present a detailed study of the host galaxy of GRB 011121 (at z = 0.36) based on high-resolution imaging in 5 broad-band, optical and near-infrared filters with HST and VLT/ISAAC. The surface brightness profile of this galaxy is best fitted by a Sersic law with index ~ 2 - 2.5 and a rather large effective radius (~ 7.5 kpc). Both the morphological analysis and the F450W - F702W colour image suggest that the host galaxy of GRB 011121 is either a disk-system with a rather small bulge, or one hosting a central, dust-enshrouded starburst. Hence, we modeled the integrated spectral energy distribution of this galaxy by combining stellar population and radiative transfer models, assuming properties representative of nearby starburst or normal star-forming, Sbc-like galaxies. A range of plausible fitting solutions indicates that the host galaxy of GRB 011121 has a stellar mass of 3.1 - 6.9 x10^9 Msun, stellar populations with a maximum age ranging from 0.4 to 2 Gyr, and a metallicity ranging from 1 to 2... 9. Low redshift quasars in the SDSS Stripe 82. Host galaxy colors and close environment Bettoni, D; Kotilainen, J K; Karhunen, K; Uslenghi, M 2015-01-01 We present a photometrical and morphological multicolor study of the properties of low redshift (z<0.3) quasar hosts based on a large and homogeneous dataset of quasars derived from the Sloan Digital Sky Survey (DR7). We used quasars that were imaged in the SDSS Stripe82 that is up to 2 mag deeper than standard Sloan images. This sample is part of a larger dataset of ~400 quasars at z<0.5 for which both the host galaxies and their galaxy environments were studied (Falomo et al. 2014,Karhunen et al. 2014). For 52 quasars we undertake a study of the color of the host galaxies and of their close environments in u,g,r,i and z bands. We are able to resolve almost all the quasars in the sample in the filters g,r,i and z and also in$u$for about 50% of the targets. We found that the mean colors of the QSO host galaxy (g-i=0.82+-0.26; r-i=0.26+-0.16 and u-g=1.32+-0.25) are very similar to the values of a sample of inactive galaxies matched in terms of redshift and galaxy luminosity with the quasar sample. Ther... 10. Black hole accretion and host galaxies of obscured quasars in XMM-COSMOS Mainieri, V; Merloni, A; Aller, M; Carollo, M; Iwasawa, K; Koekemoer, A M; Mignoli, M; Silverman, J D; Bolzonella, M; Brusa, M; Comastri, A; Gilli, R; Halliday, C; Ilbert, O; Lusso, E; Salvato, M; Vignali, C; Zamorani, G; Contini, T; Kneib, J -P; Fevre, O Le; Lilly, S; Renzini, A; Scodeggio, M; Balestra, I; Bardelli, S; Caputi, K; Coppa, G; Cucciati, O; de la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Knobel, C; Kovac, K; Lamareille, F; Borgne, J -F Le; Brun, V Le; Maier, C; Nair, P; Pello, R; Peng, Y; Montero, E Perez; Pozzetti, L; Ricciardelli, E; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Zucca, E; Aussel, H; Capak, P; Cappelluti, N; Elvis, M; Fiore, F; Hasinger, G; Impey, C; Floc'h, E Le; Scoville, N; Taniguchi, Y; Trump, J 2011-01-01 We explore the connection between black hole growth at the center of obscured quasars selected from the XMM-COSMOS survey and the physical properties of their host galaxies. We study a bolometric regime ( 8 x 10^45 erg/s) where several theoretical models invoke major galaxy mergers as the main fueling channel for black hole accretion. We confirm that obscured quasars mainly reside in massive galaxies (Mstar>10^10 Msun) and that the fraction of galaxies hosting such powerful quasars monotonically increases with the stellar mass. We stress the limitation of the use of rest-frame color-magnitude diagrams as a diagnostic tool for studying galaxy evolution and inferring the influence that AGN activity can have on such a process. We instead use the correlation between star-formation rate and stellar mass found for star-forming galaxies to discuss the physical properties of the hosts. We find that at z ~1, ~62% of Type-2 QSOs hosts are actively forming stars and that their rates are comparable to those measured for ... 11. A Statistical Study of H I Gas in Nearby Narrow-Line AGN-Hosting Galaxies Zhu, Yi-Nan 2015-01-01 As a quenching mechanism, AGN feedback could suppress on-going star formation in their host galaxies. On the basis of a sample of galaxies selected from ALFALFA HI survey, the dependence of their HI mass M[HI], stellar mass M[*] & HI-to-stellar mass ratio M[HI]/M[*] on various tracers of AGN activity are presented and analyzed in this paper. Almost all the AGN-hostings in this sample are gas-rich galaxies, and there is no any evidence to be shown to indicate that the AGN activity could increase/decrease either M[HI] or M[HI]/M[*]. The cold neutral gas can not be fixed positions accurately just based on available HI data due to the large beam size of ALFALFA survey. In addition, even though AGN-hostings are more easily detected by HI survey compared with absorption line galaxies, these two types of galaxies show similar star formation history. If an AGN-hosting would ultimately evolve into an old red galaxy with few cold gas, then when and how the gas has been exhausted have to be solved by future hypothes... 12. Demographics of the Galaxies Hosting Short-duration Gamma-Ray Bursts Fong, Wen-fai; Chornock, Ryan; Margutti, Raffaella; Levan, Andrew J; Tanvir, Nial R; Tunnicliffe, Rachel L; Czekala, Ian; Fox, Derek B; Perley, Daniel A; Cenko, S Bradley; Zauderer, B Ashley; Laskar, Tanmoy; Persson, S Eric; Monson, Andrew J; Kelson, Daniel D; Birk, Christoph; Murphy, David; Servillat, Mathieu; Anglada, Guillem 2013-01-01 We present observations of the afterglows and host galaxies of three short-duration gamma-ray bursts (GRBs): 100625A, 101219A and 110112A. We find that GRB 100625A occurred in a z=0.452 early-type galaxy with a stellar mass of 4.6e9 M_Sun and a stellar population age of 0.7 Gyr, and GRB 101219A originated in a star-forming galaxy at z=0.718 with a stellar mass of 1.4e9 M_Sun, a star formation rate of 16 M_Sun yr^-1, and a stellar population age of 50 Myr. We also report the discovery of the optical afterglow of GRB 110112A, which lacks a coincident host galaxy to i>26 mag and we cannot conclusively identify any field galaxy as a possible host. The bursts have inferred circumburst densities of ~1e-4-1 cm^-3, and isotropic-equivalent gamma-ray and kinetic energies of 1e50-1e51 erg. These events highlight the diversity of galaxies that host short GRBs. To quantify this diversity, we use the sample of 36 Swift short GRBs with robust associations to an environment (~1/2 of 68 short bursts detected by Swift to May ... 13. The MUSE QSO Blind Survey: A Census of Absorber Host Galaxies Straka, Lorrie A.; MUSE GTO Consortium 2017-03-01 Understanding the distribution of gas in galaxies and its interaction with the IGM is crucial to complete the picture of galaxy evolution. At all redshifts, absorption features seen in QSO spectra serve as a unique probe of the gaseous content of foreground galaxies and the IGM, extending out to 200 kpc. Studies show that star formation history is intimately related to the co-evolution of galaxies and the IGM. In order to study the environments traced by absorption systems and the role of inflows and outflows, it is critical to measure the emission properties of host galaxies and their halos. We overcome the challenge of detecting absorption host galaxies with the MUSE integral field spectrograph on VLT. MUSE's large field of view and sensitivity to emission lines has allowed a never-before seen match between the number density of absorbers along QSO sightlines and the number density of emission line galaxies within 200 kpc of the QSO. These galaxies represent a sample for which previously elusive connections can be made between mass, metallicity, SFR, and absorption. 14. Do Typical Galaxies in Adolescence Already Host Growing Black Holes? Trump, Jonathan 2012-10-01 This archival grism proposal achieves a 100-fold gain in high-quality {5+sigma} information for discovering which properties of adolescent {0.7ACS 800L pointings of 2-orbit grism data in the CANDELS fields, for a sample of 3000 galaxies reaching SFR 5 Msun/yr and stellar masses of log{M*/Msun} 9 at z 1.5. We will leverage spatially-resolved line ratios to uniquely distinguish a nuclear AGN from extended low-metallicity or shocked gas. Compared to our 30-galaxy published sample that hints at AGNs in low-mass z 2 galaxies {Trump et al. 2011}, this 3000 galaxy sample enables a 100-fold gain in divisions by galaxy morphology, SFR, and stellar mass to discover which galaxy properties correlate most with rapid SMBH growth. We will stack the deep {0.8-4 Ms} Chandra data available in these fields as an independent check of the grism AGN/SF diagnostics. The unique ancillary data in these fields also include ACS+WFC3 imaging for morphologies, deep multiwavelength data for well-sampled SEDs and stellar masses, and previous optical {and future near-IR} spectroscopy to supplement the G141 coverage. Based on discussions with the GOODS-N and 3D-HST teams, our proposed AGN science does not overlap with their proposed or funded science goals. As a value-added product for the community we will release, via the public Rainbow-CANDELS database server, an atlas of spatial maps of emission lines and line ratios {and associated errors} for the entire sample of 3000 galaxies. 15. Spectroscopy of superluminous supernova host galaxies. A preference of hydrogen-poor events for extreme emission line galaxies Leloudas, G; Kruehler, T; Gorosabel, J; Christensen, L; Mehner, A; Postigo, A de Ugarte; Amorin, R; Thoene, C C; Anderson, J P; Bauer, F E; Gallazzi, A; Helminiak, K G; Hjorth, J; Ibar, E; Malesani, D; Morell, N; Vinko, J; Wheeler, J C 2014-01-01 Superluminous supernovae (SLSNe) were only discovered recently due to their preference for occurring in faint dwarf galaxies. Understanding why stellar evolution yields different types of stellar explosions in these environments is fundamental in order to both uncover the elusive progenitors of SLSNe and to study star formation in dwarf galaxies. In this paper, we present the first results of our project to study SUperluminous Supernova Host galaxIES (SUSHIES), focusing on the sample for which we have obtained spectroscopy. We show that SLSNe-I and SLSNe-R (hydrogen-poor) often (~50% in our sample) occur in a class of galaxies that is known as Extreme Emission Line Galaxies (EELGs). The probability of this happening by chance is negligible and we therefore conclude that the extreme environmental conditions and the SLSN phenomenon are related. In contrast, SLSNe-II (hydrogen-rich) occur in more massive, more metal-rich galaxies with softer radiation fields. Therefore, if SLSNe-II constitute a uniform class, th... 16. Spatially-resolved dust properties of the GRB 980425 host galaxy Michałowski, Michał J; Palazzi, E; Savaglio, S; Gentile, G; Rasmussen, J; Baes, M; Basa, S; Bianchi, S; Berta, S; Burlon, D; Ceron, J M Castro; Covino, S; Cuby, J -G; D'Elia, V; Ferrero, P; Gotz, D; Hjorth, J; Koprowski, M P; Borgne, D Le; Floc'h, E Le; Malesani, D; Murphy, T; Pian, E; Piranomonte, S; Rossi, A; Sollerman, J; Tanvir, N R; Postigo, A de Ugarte; Watson, D; van der Werf, P; Vergani, S D; Xu, D 2013-01-01 Gamma-ray bursts (GRBs) have been proposed as a tool to study star formation in the Universe, so it is crucial to investigate whether their host galaxies and immediate environments are in any way special compared with other star-forming galaxies. Here we present spatially resolved maps of dust emission of the host galaxy of the closest known GRB 980425 at z=0.0085 using our new high-resolution observations from Herschel, APEX, ALMA and ATCA. We modeled the spectral energy distributions of the host and of the star-forming region displaying the Wolf-Rayet signatures in the spectrum (WR region), located 800 pc away from the GRB position. The host is characterised by low dust content and high fraction of UV-visible star-formation, similar to other dwarf galaxies. Such galaxies are abundant in the local universe, so it is not surprising to find a GRB in one of them, assuming the correspondence between the GRB rate and star-formation. The WR region contributes substantially to the host emission at the far-infrared,... 17. The abundance of satellites depends strongly on the morphology of the host galaxy Ruiz, Pablo; Mármol-Queraltó, Esther 2015-01-01 Using the spectroscopic catalogue of the Sloan Digital Survey Data Release 10 (SDSS DR10), we have explored the abundance of satellites around a sample of 307 massive (M_star > 10^11 M_sun) local (z 10^9 M_sun and R < 300 kpc depends drastically on the morphology of the central galaxy. The average number of satellites per galaxy host (N_Sat/N_Host) down to a mass ratio of 1:100 is: 5.5 +/- 1.0 for E hosts, 2.7 +/- 0.4 for S0, 1.4 +/- 0.3 for Sa and 1.2 +/- 0.3 for Sb/c. The amount of stellar mass enclosed by the satellites around massive E-type galaxies is a factor of 2, 4, and 6 larger than the mass in the satellites of S0, Sa and Sb/c-types, respectively. If these satellites would eventually infall into the host galaxies, for all the morphological types, the merger channel will be largely dominated by satellites with a mass ratio satellite-host$\\mu$< 0.1. The fact that massive elliptical galaxies have a significant larger number of satellites than massive spirals could point out that elliptical gal... 18. Supermassive black holes and central star clusters: Connection with the host galaxy kinematics and color Zasov, A. V.; Cherepashchuk, A. M. 2013-11-01 The relationship between the masses of the central, supermassive black holes ( M bh) and of the nuclear star clusters ( M nc) of disk galaxies with various parameters galaxies are considered: the rotational velocity at R = 2 kpc V (2), the maximum rotational velocity V max, the indicative dynamical mass M 25, the integrated mass of the stellar population M *, and the integrated color index B-V. The rotational velocities andmasses of the central objects were taken from the literature. Themass M nc correlatesmore closely with the kinematic parameters and the disk mass than M bh, including with the velocity V max, which is closely related to the virial mass of the dark halo. On average, lenticular galaxies are characterized by higher masses M bh compared to other types of galaxies with similar characteristics. The dependence of the blackhole mass on the color index is bimodal: galaxies of the red group (red-sequence) with B-V >0.6-0.7 which are mostly early-type galaxies with weak star formation, differ appreciably from blue galaxies, which have higher values of M nc and M bh. At the dependences we consider between the masses of the central objects and the parameters of the host galaxies (except for the dependence of M bh on the central velocity dispersion), the red-group galaxies have systematically higher M bh values, even when the host-galaxy parameters are similar. In contrast, in the case of nuclear star clusters, the blue and red galaxies form unified sequences. The results agree with scenarios in which most red-group galaxies form as a result of the partial or complete loss of interstellar gas in a stage of high nuclear activity in galaxies whose central black-hole masses exceed 106-107 M ⊙ (depending on the mass of the galaxy itself). The bulk of disk galaxies with M bh > 107 M ⊙ are lenticular galaxies (types S0, E/S0) whose disks are practically devoid of gas. 19. Supermassive black holes: Coevolution (or not) of black holes and host galaxies Kormendy, John 2013-07-01 Supermassive black holes (BHs) have been found in 75 galaxies by observing spatially resolved dynamics. The Hubble Space Telescope (HST) revolutionized BH work by advancing the subject from its proof of concept' phase into quantitative studies of BH demographics. Most influential was the discovery of a tight correlation between BH masses M • and the velocity dispersions σ of stars in the host galaxy bulge components at radii where the stars mostly feel each other and not the BH. Together with correlations between M • and bulge luminosity, with the missing light' that defines galaxy cores, and with numbers of globular clusters, this has led to the conclusion that BHs and bulges coevolve by regulating each other's growth. This simple picture with one set of correlations for all galaxies dominated BH work in the past decade. New results are now replacing the above, simple story with a richer and more plausible picture in which BHs correlate differently with different kinds of galaxy components. BHs with masses of 105-106 M ⊙ live in some bulgeless galaxies. So classical (merger-built) bulges are not necessary equipment for BH formation. On the other hand, while they live in galaxy disks, BHs do not correlate with galaxy disks or with disk-grown pseudobulges. They also have no special correlation with dark matter halos beyond the fact that halo gravity controls galaxy formation. This leads to the suggestion that there are two modes of BH feeding, (1) local, secular and episodic feeding of small BHs in largely bulgeless galaxies that involves too little energy feedback to drive BH-host-galaxy coevolution and (2) global feeding in major galaxy mergers that rapidly grows giant BHs in short-duration events whose energy feedback does affect galaxy formation. After these quasar-like phases, maintenance-mode BH feedback into hot, X-ray-emitting gas continues to have a primarily negative effect in preventing late-time star formation when cold gas or gas-rich galaxies 20. Tracing the evolution of Active Galactic Nuclei host galaxies over the last 9 Gyrs of Cosmic time Goulding, Andy D; Hickox, Ryan C; Jones, Christine; Murray, Stephen S; Paggi, Alessandro; Ashby, Matthew L N; Coil, Alison L; Cooper, Michael C; Huang, Jiasheng; Kraft, Ralph; Newman, Jeffrey A; Weiner, Benjamin J; Willner, Steven P 2013-01-01 We present the results of a combined galaxy population analysis for the host galaxies of active galactic nuclei (AGN) identified at 0 < z < 1.4 within the SDSS, Bootes and DEEP2 surveys. We identified AGN in a uniform and unbiased manner at X-ray, infrared and radio wavelengths. Supermassive black holes undergoing radiatively-efficient accretion (detected as X-ray and/or infrared AGN) appear to be hosted in a separate and distinct galaxy population than AGN undergoing powerful mechanically dominated accretion (radio AGN). Consistent with some previous studies, radiatively efficient AGN appear to be preferentially hosted in modest star-forming galaxies, with little dependence on AGN or galaxy luminosity. AGN exhibiting radio-emitting jets due to mechanically-dominated accretion are almost exclusively observed in massive, passive galaxies. Crucially, we now provide strong evidence that the observed host-galaxy trends are independent of redshift. In particular, these different accretion-mode AGN have remai... 1. A nearby GRB host prototype for z~7 Lyman-break galaxies: Spitzer-IRS and X-shooter spectroscopy of the host galaxy of GRB031203 Watson, D; Christensen, L; O'Halloran, B; Michałowski, M; Hjorth, J; Malesani, D; Fynbo, J P U; Gordon, K D; Cerón, J M Castro 2010-01-01 Gamma-ray burst (GRB) host galaxies have been studied extensively in optical photometry and spectroscopy. Here we present the first mid-infrared spectrum of a GRB host, HG031203. It is one of the nearest GRB hosts at z=0.1055, allowing both low and high-resolution spectroscopy with Spitzer-IRS. Medium resolution UV-to-K-band spectroscopy with the X-shooter spectrograph on the VLT is also presented, along with Spitzer IRAC and MIPS photometry, as well as radio and sub-mm observations. These data allow us to construct a UV-to-radio spectral energy distribution with almost complete spectroscopic coverage from 0.3-35 micron of a GRB host galaxy for the first time, potentially valuable as a template for future model comparisons. The IRS spectra show strong, high-ionisation fine structure line emission indicative of a hard radiation field in the galaxy, suggestive of strong ongoing star-formation and a very young stellar population. The selection of HG031203 via the presence of a GRB suggests that it might be a use... 2. CEPHEID VARIABLES IN THE MASER-HOST GALAXY NGC 4258 Hoffmann, Samantha L.; Macri, Lucas M., E-mail: [email protected] [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States) 2015-06-15 We present results of a ground-based survey for Cepheid variables in NGC 4258. This galaxy plays a key role in the Extragalactic Distance Scale due to its very precise and accurate distance determination via very long baseline interferometry observations of water masers. We imaged two fields within this galaxy using the Gemini North telescope and the Gemini Multi-Object Spectrograph, obtaining 16 epochs of data in the Sloan Digital Sky Survey gri bands over 4 yr. We carried out point-spread function photometry and detected 94 Cepheids with periods between 7 and 127 days, as well as an additional 215 variables which may be Cepheids or Population II pulsators. We used the Cepheid sample to test the absolute calibration of theoretical gri Period–Luminosity relations and found good agreement with the maser distance to this galaxy. The expected data products from the Large Synoptic Survey Telescope should enable Cepheid searches out to at least 10 Mpc. 3. Cepheid Variables in the Maser-Host Galaxy NGC 4258 Hoffmann, Samantha L 2015-01-01 We present results of a ground-based survey for Cepheid variables in NGC 4258. This galaxy plays a key role in the Extragalactic Distance Scale due to its very precise and accurate distance determination via VLBI observations of water masers. We imaged two fields within this galaxy using the Gemini North telescope and GMOS, obtaining 16 epochs of data in the SDSS gri bands over 4 years. We carried out PSF photometry and detected 94 Cepheids with periods between 7 and 127 days, as well as an additional 215 variables which may be Cepheids or Population II pulsators. We used the Cepheid sample to test the absolute calibration of theoretical gri Period-Luminosity relations and found good agreement with the maser distance to this galaxy. The expected data products from the Large Synoptic Survey Telescope (LSST) should enable Cepheid searches out to at least 10 Mpc. 4. Host-galaxy Properties of 32 Low-redshift Superluminous Supernovae from the Palomar Transient Factory Perley, D. A.; Quimby, R. M.; Yan, L.; Vreeswijk, P. M.; De Cia, A.; Lunnan, R.; Gal-Yam, A.; Yaron, O.; Filippenko, A. V.; Graham, M. L.; Laher, R.; Nugent, P. E. 2016-10-01 We present ultraviolet through near-infrared photometry and spectroscopy of the host galaxies of all superluminous supernovae (SLSNe) discovered by the Palomar Transient Factory prior to 2013 and derive measurements of their luminosities, star formation rates, stellar masses, and gas-phase metallicities. We find that Type I (hydrogen-poor) SLSNe (SLSNe I) are found almost exclusively in low-mass ({M}* \\lt 2× {10}9 {M}ȯ ) and metal-poor (12 + log10[O/H] \\lt 8.4) galaxies. We compare the mass and metallicity distributions of our sample to nearby galaxy catalogs in detail and conclude that the rate of SLSNe I as a fraction of all SNe is heavily suppressed in galaxies with metallicities ≳ 0.5 {Z}ȯ . Extremely low metallicities are not required and indeed provide no further increase in the relative SLSN rate. Several SLSN I hosts are undergoing vigorous starbursts, but this may simply be a side effect of metallicity dependence: dwarf galaxies tend to have bursty star formation histories. Type II (hydrogen-rich) SLSNe (SLSNe II) are found over the entire range of galaxy masses and metallicities, and their integrated properties do not suggest a strong preference for (or against) low-mass/low-metallicity galaxies. Two hosts exhibit unusual properties: PTF 10uhf is an SLSN I in a massive, luminous infrared galaxy at redshift z = 0.29, while PTF 10tpz is an SLSN II located in the nucleus of an early-type host at z = 0.04. 5. The Black Hole-Bulge Mass Relation in Megamaser Host Galaxies Läsker, Ronald; Greene, Jenny E.; Seth, Anil; van de Ven, Glenn; Braatz, James A.; Henkel, Christian; Lo, K. Y. 2016-07-01 We present Hubble Space Telescope (HST) images for nine megamaser disk galaxies with the primary goal of studying photometric BH-galaxy scaling relations. The megamaser disks provide the highest-precision extragalactic BH mass measurements, while our high-resolution HST imaging affords us the opportunity to decompose the complex nuclei of their late-type hosts in detail. Based on the morphologies and shapes of the galaxy nuclei, we argue that most of these galaxies’ central regions contain secularly evolving components (pseudo-bulges), and in many cases we photometrically identify co-existing “classical” bulge components as well. Using these decompositions, we draw the following conclusions. (1) The megamaser BH masses span two orders of magnitude (106-{10}8 {M}⊙ ) while the stellar mass of their spiral host galaxies are all ˜ {10}11 {M}⊙ within a factor of three. (2) The BH masses at a given bulge mass or total stellar mass in the megamaser host spiral galaxies tend to be lower than expected when compared to an extrapolation of the BH-bulge relation based on early-type galaxies. (3) The observed large intrinsic scatter of BH masses in the megamaser host galaxies raises the question of whether scaling relations exist in spiral galaxies. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program 12185. 6. The host galaxies of BL Lac objects in the near-infrared Kotilainen, J K; Scarpa, R 1998-01-01 We present the results of near-infrared H band (1.65 microns) imaging of 11 BL Lac objects with redshifts ranging from z = 0.05 to 0.9. We are able to clearly detect the host galaxy in seven low redshift (z<=0.24) BL Lacs, while the four unresolved BL Lacs have either high or unknown redshift. The galaxies hosting the low redshift BL Lacs are large (average bulge scale length R(e) = 8.8+-9.9 kpc) and luminous (average M(H) = -25.8+-0.5), i.e. slightly brighter than the typical galaxy luminosity L* (M*(H) = -25.0+-0.2), and of similar luminosity to or slightly fainter than brightest cluster galaxies (M(H) = -26.3+-0.3). The average optical/near-infrared colour and colour gradient of the BL Lac hosts (R-H = 2.2+-0.5; d(R-H)/d(log r) = -0.09$+-0.04) are consistent with the hosts being normal ellipticals, indicating that the nuclear activity has only a marginal effect on the star formation history and other properties of the hosts. The BL Lac hosts appear slightly less luminous than those of higher redshift fl...
7. The Post-Starburst Evolution of Tidal Disruption Event Host Galaxies
French, K Decker; Zabludoff, Ann
2016-01-01
Tidal Disruption Events (TDEs) favor quiescent host galaxies with strong Balmer absorption lines. Here we study eight hosts of optical/UV-detected TDEs to determine the duration of the recent star formation episode, the time elapsed since it ended, and the fraction of stellar mass produced. Most hosts (6/8) have had short recent starbursts of <200 Myr as opposed to a slower decline in star formation. TDE host galaxies span a wide range of post-starburst ages (60-600 Myr for 6/8 galaxies), indicating that TDEs are not limited to a specific time in their hosts' post-starburst evolution. If the disrupted star was a main sequence star that formed in the burst or before, the post-burst ages provide an independent constraint on its likely mass, excluding O, B and the most massive A stars. If the starburst arose from a galaxy merger, the time elapsed since the starburst began constrains the coalescence timescale and thus limits the merger mass ratio to more equal than 12:1 in most (7/8) TDE hosts. This uncommon r...
8. The chosen few: the low mass halos that host faint galaxies
Sawala, Till; Fattahi, Azadeh; Navarro, Julio F; Theuns, Tom; Bower, Richard G; Crain, Robert A; Furlong, Michelle; Jenkins, Adrian; Schaller, Matthieu; Schaye, Joop
2014-01-01
Since reionization prevents star formation in most halos below 3 x 10^9 solar masses, dwarf galaxies only populate a fraction of existing dark matter halos. We use hydrodynamic cosmological simulations of the Local Group to study the discriminating factors for galaxy formation in the early Universe and connect them to the present-day properties of galaxies and halos. A combination of selection effects related to reionization, and the subsequent evolution of halos in different environments, introduces strong biases between the population of halos that host dwarf galaxies, and the total halo population. Halos that host galaxies formed earlier and are more concentrated. In addition, halos more affected by tidal stripping are more likely to host a galaxy for a given mass or maximum circular velocity, vmax, today. Consequently, satellite halos are populated more frequently than field halos, and satellite halos of 10^8 - 10^9 solar masses or vmax of 12 - 20 km/s, similar to the Local Group dwarf spheroidals, have e...
9. The Relation between Luminous AGNs and Star Formation in Their Host Galaxies
Xu, Lei; Egami, E; Haines, C P; Pereira, M J; Smith, G P
2015-01-01
We study the relation of active galactic nuclei (AGNs) to star formation in their host galaxies. Our sample includes 205 Type-1 and 85 Type-2 AGNs, 162 detected with Herschel, from fields surrounding 30 galaxy clusters in the Local Cluster Substructure Survey (LoCuSS). The sample is identified by optical line widths and ratios after selection to be brighter than 1 mJy at 24 microns. We show that Type-2 AGN [OIII]5007 line fluxes at high z can be contaminated by their host galaxies with typical spectrograph entrance apertures (but our sample is not compromised in this way). We use spectral energy distribution (SED) templates to decompose the galaxy SEDs and estimate star formation rates, AGN luminosities, and host galaxy stellar masses (described in an accompanying paper). The AGNs arise from massive black holes (~ 3 X 10^8 Msun) accreting at ~ 10% of the Eddington rate and residing in galaxies with stellar mass > 3 X 10^{10} Msun; those detected with Herschel have IR luminosity from star formation in the rang...
10. Supernovae and their host galaxies - II. The relative frequencies of supernovae types in spirals
Hakobyan, A A; Adibekyan, V Zh; Petrosian, A R; Aramyan, L S; Kunth, D; Mamon, G A; de Lapparent, V; Bertin, E; Gomes, J M; Turatto, M
2014-01-01
(Abridged) In this second paper of a series, we present an analysis of the relative frequencies of different supernova (SN) types in spirals with various morphologies and in barred or unbarred galaxies. We use a well-defined and homogeneous sample of host galaxies from the Sloan Digital Sky Survey (SDSS) in different stages of galaxy-galaxy interaction. We propose that the underlying mechanisms shaping the number ratios of SNe types can be interpreted within the framework of interaction-induced star formation, in addition to the known relations between morphologies and stellar populations. We find a strong trend in behaviour of the NIa/NCC ratio depending on host morphology, such that early spirals include more type Ia SNe, reflecting the change of the specific star formation rate (SFR). The NIbc/NII ratio is higher in a broad bin of early-type hosts. The NIa/NCC ratio is nearly constant when changing from normal, perturbed to interacting galaxies, then declines in merging galaxies, whereas it jumps to the hi...
11. The dark nature of GRB 051022 and its host galaxy
Castro-Tirado, A J; McBreen, S; Gorosabel, J; Guziy, S; Delgado, R M Gonzalez; Bihain, G; Fakthullin, T; Pandey, S B; Jelinek, M; Postigo, A de Ugarte; Sokolov, V; Misra, K; Sagar, R; Bama, P; Kamble, A P; Anupama, G C; Licandro, J; Aceituno, F J; Neri, R
2007-01-01
We present multiwavelength (X-ray/optical/near-infrared/millimetre) observations of GRB 051022 between 2.5 hours and ~1.15 yr after the event. It is the most intense gamma-ray burst (~ 10^-4 erg cm^-2) detected by HETE-2, with the exception of the nearby GRB 030329. Optical and near infrared observations did not detect the afterglow despite a strong afterglow at X-ray wavelengths. Millimetre observations at Plateau de Bure (PdB) detected a source and a flare, confirming the association of this event with a moderately bright (R = 21.5) galaxy. Spectroscopic observations of this galaxy show strong [O II], Hbeta and [O III] emission lines at a redshift of 0.809. The spectral energy distribution of the galaxy implies Av (rest frame) = 1.0 and a starburst occuring ~ 25 Myr ago, during which the star-forming-rate reached >= 25 Msun/yr. In conjunction with the spatial extent (~ 1'') it suggests a very luminous (Mv = - 21.8) blue compact galaxy, for which we also find with Z Zsun. The X-ray spectrum shows evidence of...
12. The Hubble Diagram of Type Ia Supernovae as a Function of Host Galaxy Morphology
Sullivan, M; Aldering, G; Amanullah, R; Astier, Pierre; Blanc, G; Burns, M S; Conley, A; Deustua, S E; Doi, M; Fabbro, S; Folatelli, G; Fruchter, A S; Garavini, G; Gibbons, R; Goldhaber, Gerson; Goobar, A; Groom, D E; Hardin, D; Hook, I; Howell, D A; Irwin, M; Kim, A G; Knop, R A; Lidman, C E; McMahon, R; Méndez, J; Nobili, S; Nugent, P; Pain, R; Panagia, N; Pennypacker, C R; Perlmutter, S; Quimby, R; Raux, J; Regnault, N; Ruiz-Lapuente, P; Schaefer, B; Schahmaneche, K; Spadafora, A L; Walton, N A; Wang, L; Wood-Vasey, W M; Yasuda, N
2003-01-01
(Abridged) We present new results on the Hubble diagram of distant type Ia supernovae (SNe Ia) segregated according to the type of host galaxy. This makes it possible to check earlier evidence for a cosmological constant by explicitly comparing SNe residing in galaxies likely to contain negligible dust with the larger sample. The cosmological parameters derived from these SNe Ia hosted by presumed dust-free early-type galaxies supports earlier claims for a cosmological constant, which we demonstrate at 5 sigma significance, and the internal extinction implied is small even for late-type systems (A_B<0.2). Thus, our data demonstrate that host galaxy extinction is unlikely to systematically dim distant SNe Ia in a manner that would produce a spurious cosmological constant. We classify the host galaxies of 39 distant SNe discovered by the Supernova Cosmology Project (SCP) using the combination of HST STIS imaging, Keck ESI spectroscopy and ground-based broad-band photometry. We compare with a low-redshift sam...
13. The galaxy hosts and large-scale environments of short-hard (gamma)-ray bursts
Prochaska, J X; Bloom, J S; Chen, H; Foley, R J; Perley, D A; Ramirez-Ruiz, E; Granot, J; Lee, W H; Pooley, D; Alatalo, K; Hurley, K; Cooper, M C; Dupree, A K; Gerke, B F; Hansen, B S; Kalirai, J S; Newman, J A; Rich, R M; Richer, H; Stanford, S A; Stern, D; van Breugel, W
2006-04-07
The nature of the progenitors of short duration, hard spectrum, gamma-ray bursts (GRBs) has remained a mystery. Even with the recent localizations of four short-hard GRBs, no transient emission has been found at long wavelengths that directly constrains the progenitor nature. Instead, as was the case in studying the different morphological subclasses of supernovae and the progenitors of long-duration GRBs, we suggest that the progenitors of short bursts can be meaningfully constrained by the environment in which the bursts occur. Here we present the discovery spectra of the galaxies that hosted three short-hard GRBs and the spectrum of a fourth host. The results indicate that these environments, both at the galaxy scale and galaxy-cluster scale, differ substantially from those of long-soft GRBs. The spatial offset of three bursts from old and massive galaxy hosts strongly favors an origin from the merger of compact stellar remnants, such as double neutron stars or a neutron-star black hole binary. The star-forming host of another GRB provides confirmation that, like supernovae of Type Ia, the progenitors of short-hard bursts are created in all galaxy types. This indicates a class of progenitors with a wide distribution of delay times between formation and explosion.
14. The nuclear properties and extended morphologies of powerful radio galaxies: the roles of host galaxy and environment
Miraghaei, H.; Best, P. N.
2017-01-01
Powerful radio galaxies exist as either compact or extended sources, with the extended sources traditionally classified by their radio morphologies as Fanaroff-Riley (FR) type I and II sources. FRI/II and compact radio galaxies have also been classified by their optical spectra into two different types: high excitation (HERG; quasar-mode) and low excitation (LERG; jet-mode). We present a catalogue of visual morphologies for a complete sample of >1000 1.4-GHz-selected extended radio sources from the Sloan Digital Sky Survey. We study the environment and host galaxy properties of FRI/II and compact sources, classified into HERG/LERG types, in order to separate and distinguish the factors that drive the radio morphological variations from those responsible for the spectral properties. Comparing FRI LERGs with FRII LERGs at fixed stellar mass and radio luminosity, we show that FRIs typically reside in richer environments and are hosted by smaller galaxies with higher mass surface density; this is consistent with extrinsic effects of jet disruption driving the FR dichotomy. Using matched samples of HERGs and LERGs, we show that HERG host galaxies are more frequently star-forming, with more evidence for disk-like structure than LERGs, in accordance with currently-favoured models of fundamentally different fuelling mechanisms. Comparing FRI/II LERGs with compact LERGs, we find the primary difference is that compact objects typically harbour less massive black holes. This suggests that lower-mass black holes may be less efficient at launching stable radio jets, or do so for shorter times. Finally, we investigate rarer sub-classes: wide-angle tail, head-tail, FR-hybrid and double-double sources.
15. Preliminary Results on VLT K-band Imaging Observations of GRB Host Galaxies
E. Le Floc’h; I. F. Mirabel; P.-A. Duc
2002-03-01
We have obtained -band imaging observations of Gamma-Ray Burst (GRB) host galaxies with the near-infrared spectro-imager ISAAC installed on the Very Large Telescope at Paranal (Chile). The derived magnitudes, combined with other photometric data taken from the literature, are used to investigate the – colors of GRB hosts. We do not find any extremely reddened starbursts in our sample, despite the capability of GRBs to trace star formation even in dusty regions. The observed – colors are on the contrary typical of irregular and spiral blue galaxies at high redshift.
16. VizieR Online Data Catalog: SN Ia host-galaxy/cosmological parameters (Campbell+, 2016)
Campbell, H.; Fraser, M.; Gilmore, G.
2016-11-01
We have investigated correlations between SNe Ia light curves and their host galaxies and look at the effect on the cosmological constraints. For this we have used the sample of 581 photometrically classified SNe Ia from Campbell et al. (2013, Cat. J/ApJ/763/88). This sample was assembled from three years of photometry from the SDSS-II SN Survey, together with BOSS spectroscopy of the host galaxies of transients. We use the stellar population parameters derived from the BOSS DR10 results (Ahn et al., 2012ApJS..203...21A, Cat V/139) (1 data file).
17. Near-infrared imaging of the host galaxies of intermediate redshift steep spectrum radio quasars
Kotilainen, J K
2000-01-01
We present the results of near-infrared H-band (1.65 microns) imaging of 19 steep spectrum radio quasars (SSRQ) in the redshift range 0.5 < z < 1.0. This sample of SSRQs is matched with our previously studied complete sample of 20 flat spectrum radio quasars (FSRQ) with respect to redshift and optical and radio luminosity. We are able to clearly detect the host galaxy in 10 (53 %) SSRQs and marginally in 6 (32 %) others, while the host remains unresolved in 3 (16 %) SSRQs. The galaxies hosting the SSRQs are large (average bulge scale-length R(e) = 9.0+-1.7 kpc) and luminous (average M(H) = -27.2+-1.1). They are, therefore, about 2 mag more luminous than the typical galaxy luminosity L* (M*(H) = -25.0+-0.2), and about 1 mag more luminous than the brightest cluster galaxies (M(H) = -26.3+-0.3). The SSRQ hosts appear to have similar luminosity to those of the FSRQ hosts (M(H) = -27), and they fall between the luminosities of lower redshift (M(H) = -26) and higher redshift (M(H) = -29) radio-loud quasars. T...
18. The Spitzer/Swift Gamma-Ray Burst Host Galaxy Legacy Survey
Perley, Daniel; Berger, Edo; Butler, Nathaniel; Cenko, S. Bradley; Chary, Ranga-Ram; Cucchiara, Antonino; Ellis, Richard; Fong, Wen-fai; Fruchter, Andrew; Fynbo, Johan; Gehrels, Neil; Graham, John; Greiner, Jochen; Hjorth, Jens; Hunt, Leslie; Jakobsson, Pall; Kruehler, Thomas; Laskar, Tanmoy; Le Floc'h, Emerich; Levan, Andrew; Levesque, Emily; Littlejohns, Owen; Malesani, Daniele; Michalowski, Michal; Milvang-Jensen, Bo; Prochaska, J. Xavier; Salvaterra, Ruben; Schulze, Steve; Schady, Patricia; Tanvir, Nial; de Ugarte Postigo, Antonio; Vergani, Susanna; Watson, Darach
2016-08-01
Long-duration gamma-ray bursts act as beacons to the sites of star-formation in the distant universe. GRBs reveal galaxies too faint and star-forming regions too dusty to characterize in detail using any other method, and provide a powerful independent constraint on the evolution of the cosmic star-formation rate density at high-redshift. However, a full understanding of the GRB phenomenon and its relation to cosmic star-formation requires connecting the observations obtained from GRBs to the properties of the galaxies hosting them. The large majority of GRBs originate at moderate to high redshift (z>1) and Spitzer has proven crucial for understanding the host population, given its unique ability to observe the rest-frame NIR and its unrivaled sensitivity and efficiency. We propose to complete a comprehensive public legacy survey of the Swift GRB host population to build on our earlier successes and push beyond the statistical limits of previous, smaller efforts. Our survey will enable a diverse range of GRB and galaxy science including: (1) to quantitatively and robustly map the connection between GRBs and cosmic star-formation to constrain the GRB progenitor and calibrate GRB rate-based measurements of the high-z cosmic star-formation rate; (2) to constrain the luminosity function of star-forming galaxies at the faint end and at high redshift; (3) to understand how the ISM properties seen in absorption in high-redshift galaxies unveiled by GRBs - metallicity, dust column, dust properties - connect to global properties of the host galaxies such as mass and age. Building on a decade of experience at both observatories, our observations will create an enduring joint Swift-Spitzer legacy sample - providing the definitive resource with which to examine all aspects of the GRB/galaxy connection for years to come and setting the stage for intensive JWST follow-up of the most interesting sources from our sample.
19. Spectroscopic Properties of Star-Forming Host Galaxies and Type Ia Supernova Hubble Residuals in a Nearly Unbiased Sample
D' Andrea, Chris B. [Univ. of Pennsylvania, Philadelphia, PA (United States); et al.
2011-12-20
We examine the correlation between supernova host galaxy properties and their residuals on the Hubble diagram. We use supernovae discovered during the Sloan Digital Sky Survey II - Supernova Survey, and focus on objects at a redshift of z < 0.15, where the selection effects of the survey are known to yield a complete Type Ia supernova sample. To minimize the bias in our analysis with respect to measured host-galaxy properties, spectra were obtained for nearly all hosts, spanning a range in magnitude of -23 < M_r < -17. In contrast to previous works that use photometric estimates of host mass as a proxy for global metallicity, we analyze host-galaxy spectra to obtain gas-phase metallicities and star-formation rates from host galaxies with active star formation. From a final sample of ~ 40 emission-line galaxies, we find that light-curve corrected Type Ia supernovae are ~ 0.1 magnitudes brighter in high-metallicity hosts than in low-metallicity hosts. We also find a significant (> 3{\\sigma}) correlation between the Hubble residuals of Type Ia supernovae and the specific star-formation rate of the host galaxy. We comment on the importance of supernova/host-galaxy correlations as a source of systematic bias in future deep supernova surveys.
20. The Mean Star-Forming Properties of QSO Host Galaxies
Rosario, D J; Lutz, D; Netzer, H; Trump, J R; Silverman, J D; Schramm, M; Lusso, E; Berta, S; Bongiorno, A; Brusa, M; Förster-Schreiber, N M; Genzel, R; Lilly, S; Magnelli, B; Mainieri, V; Maiolino, R; Merloni, A; Mignoli, M; Nordon, R; Popesso, P; Salvato, M; Santini, P; Tacconi, L J; Zamorani, G
2013-01-01
Quasi-stellar objects (QSOs) occur in galaxies in which supermassive black holes (SMBHs) are growing substantially through rapid accretion of gas. Many popular models of the co-evolutionary growth of galaxies and SMBHs predict that QSOs are also sites of substantial recent star formation, mediated by important processes, such as major mergers, which rapidly transform the nature of galaxies. A detailed study of the star-forming properties of QSOs is a critical test of such models. We present a far-infrared Herschel/PACS study of the mean star formation rate (SFR) of a sample of spectroscopically observed QSOs to z~2 from the COSMOS extragalactic survey. This is the largest sample to date of moderately luminous AGNs studied using uniform, deep far-infrared photometry. We study trends of the mean SFR with redshift, black hole mass, nuclear bolometric luminosity and specific accretion rate (Eddington ratio). To minimize systematics, we have undertaken a uniform determination of SMBH properties, as well as an anal...
1. Host Galaxy Properties and Hubble Residuals of Type Ia Supernovae from the Nearby Supernova Factory
Childress, M J; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Chotard, N; Copin, Y; Fakhouri, H K; Gangler, E; Guy, J; Hsiao, E Y; Kerschhaggl, M; Kim, A G; Kowalski, M; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Runge, K; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A; Wu, C
2013-01-01
We examine the relationship between Type Ia Supernova (SN Ia) Hubble residuals and the properties of their host galaxies using a sample of 115 SNe Ia from the Nearby Supernova Factory (SNfactory). We use host galaxy stellar masses and specific star-formation rates fitted from photometry for all hosts, as well as gas-phase metallicities for a subset of 69 star-forming (non-AGN) hosts, to show that the SN Ia Hubble residuals correlate with each of these host properties. With these data we find new evidence for a correlation between SN Ia intrinsic color and host metallicity. When we combine our data with those of other published SN Ia surveys, we find the difference between mean SN Ia brightnesses in low and high mass hosts is 0.077 +- 0.014 mag. When viewed in narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus of Hubble residuals at high and low host masses with a rapid transition over a short mass range (9.8 <= log(M_*/M_Sun) <= 10.4). Although metallicity has been a favored i...
2. Detection of three Gamma-Ray Burst host galaxies at $z\\sim6$
McGuire, J T W; Levan, A J; Trenti, M; Stanway, E R; Shull, J M; Wiersema, K; Perley, D A; Starling, R L C; Bremer, M; Stocke, J T; Hjorth, J; Rhoads, J E; Levesque, E M; Robertson, B; Fynbo, J P U; Ellis, R S; Fruchter, A S; Perna, R
2015-01-01
Gamma-ray bursts allow us to pinpoint and study star-forming galaxies in the early universe, thanks to their immense luminosities and association with deaths of massive stars. We present {\\em Hubble Space Telescope} Wide Field Camera 3 detections of three {\\em Swift} GRBs lying at redshifts $z = 5.913$ (GRB 130606A), $z = 6.295$ (GRB 050904), and $z = 6.327$ (GRB 140515A) in the F140W (wide-$JH$ band, $\\lambda_{\\rm{obs}}\\sim1.4\\,\\mu m$) filter. The hosts have magnitudes (corrected for Galactic extinction) of $m_{\\rm{\\lambda_{obs},AB}}= 26.26^{+0.12}_{-0.14}, 27.63^{+0.16}_{-0.18},$ and $28.23^{+0.24}_{-0.30}$ respectively. In all three cases the probability of chance coincidence of lower redshift galaxies is $\\lesssim1.5\\%$, indicating that the detected galaxies are most likely the GRB hosts. These are the first detections of high redshift ($z > 5$) GRB host galaxies in emission. The galaxies have luminosities in the range $0.1-0.7\\,L^{*}_{z=6}$ (with $M_{1600}^{*}=-20.95\\pm0.12$), along with half-light radii...
3. Host-Galaxy Properties of 32 Low-Redshift Superluminous Supernovae from the Palomar Transient Factory
Perley, Daniel A; Yan, Lin; Vreeswijk, Paul; De Cia, Annalisa; Lunnan, Ragnhild; Gal-Yam, Avishay; Yaron, Ofer; Filippenko, Alexei V; Graham, Melissa L; Nugent, Peter E
2016-01-01
We present ultraviolet through near-infrared photometry and spectroscopy of the host galaxies of all superluminous supernovae (SLSNe) discovered by the Palomar Transient Factory prior to 2013, and derive measurements of their luminosities, star-formation rates, stellar masses, and gas-phase metallicities. We find that Type I (hydrogen-poor) SLSNe are found almost exclusively in low-mass (M 0.5 Z_sun. Extremely low metallicities are not required, and indeed provide no further increase in the relative SLSN rate. Several SLSN-I hosts are undergoing vigorous starbursts, but this may simply be a side effect of metallicity dependence: dwarf galaxies tend to have bursty star-formation histories. Type-II (hydrogen-rich) SLSNe are found over the entire range of galaxy masses and metallicities, and their integrated properties do not suggest a strong preference for (or against) low-mass/low-metallicity galaxies. Two hosts exhibit unusual properties: PTF 10uhf is a Type I SLSN in a massive, luminous infrared galaxy at re...
4. The Luminosity Function of the Host Galaxies of QSOs and BL Lac Objects
Carangelo, N; Treves, A
2001-01-01
A clear insight of the galaxies hosting active galactic nuclei is of fundamental importance for understanding the processes of galaxies and nuclei formation and their cosmic evolution. A good characterization of the host galaxies properties requires images of excellent quality in order to disentangle the light of the galaxy from that of the bright nucleus. To this aim HST has provided a major improvement of data on QSOs (Disney et al. 1995; Bahcall et al. 1996, 1997; Boyce et al. 1998; McLure et al. 1999; Hamilton et al. 2000; Kukula et al. 2001) and BL Lacs (Scarpa et al. 2000, Urry et al. 2000). We present a comparative study of low redshift QSO and BL Lac host galaxy luminosity function (HGLF). To this aim we have considered samples of BL Lacs (Urry et al. 2000) and QSOs (Bahcall et al. 1997; Boyce et al. 1998; McLure et al. 1999) that have been well resolved by images obtained with WFPC2 on board of HST.
5. On the mass-metallicity relation, velocity dispersion and gravitational well depth of GRB host galaxies
Arabsalmani, Maryam; Fynbo, Johan P U; Christensen, Lise; Freudling, Wolfram; Savaglio, Sandra; Zafar, Tayyaba
2014-01-01
We analyze a sample of 16 absorption systems intrinsic to long duration GRB host galaxies at $z \\gtrsim 2$ for which the metallicities are known. We compare the relation between the metallicity and cold gas velocity width for this sample to that of the QSO-DLAs, and find complete agreement. We then compare the redshift evolution of the mass-metallicity relation of our sample to that of QSO-DLAs and find that also GRB hosts favour a late onset of this evolution, around a redshift of $\\approx 2.6$. We compute predicted stellar masses for the GRB host galaxies using the prescription determined from QSO-DLA samples and compare the measured stellar masses for the four hosts where stellar masses have been determined from SED fits. We find excellent agreement and conclude that, on basis of all available data and tests, long duration GRB-DLA hosts and intervening QSO-DLAs are consistent with being drawn from the same underlying population. GRB host galaxies and QSO-DLAs are found to have different impact parameter di...
6. Supermassive Black Hole Binaries: Environment and Galaxy Host Properties of PTA and eLISA sources
Palafox, Eva Martínez; Colín, Pedro; Gottlöber, Stefan
2014-01-01
Supermassive black hole (BH) binaries would comprise the strongest sources of gravitational waves (GW) once they reach <<1 pc separations, for both pulsar timing arrays (PTAs) and space based (SB) detectors. While BH binaries coalescences constitute a natural outcome of the cosmological standard model and galaxy mergers, their dynamical evolution is still poorly understood and therefore their abundances at different stages. We use a dynamical model for the decay of BH binaries coupled with a cosmological simulation and semi-empirical approaches to the occupation of haloes by galaxies and BHs, in order to follow the evolution of the properties distribution of galaxies hosting BH binaries candidates to decay due to GWs emission. Our models allow us to relax simplifying hypothesis about the binaries occupation in galaxies and their mass, as well as redshift evolution. Following previously proposed electromagnetic (EM) signatures of binaries in the subpc regime, that include spectral features and variabilit...
7. Hubble Space Telescope NICMOS observations of the host galaxies of powerful radio sources : Does size matter?
de Vries, WH; O'Dea, CP; Barthel, PD; Fanti, C; Fanti, R; Lehnert, MD
2000-01-01
We present near-infrared J- and K-band imaging of a sample of powerful radio source host galaxies with the Hubble Space Telescope NICMOS2 camera. These sources have been selected on their double-lobed radio structure and include a wide range of projected radio source sizes. The largest projected
8. Detailed afterglow modelling and host galaxy properties of the dark GRB 111215A
Horst, A. J. van der; Levan, A. J.; Pooley, G. G.
2015-01-01
bursts for which similar modeling work has been performed. We also present deep imaging of the host galaxy with the Keck I telescope, Spitzer Space Telescope, and Hubble Space Telescope (HST), which resulted in a well-constrained photometric redshift, giving credence to the tentative spectroscopic...
9. Neutrinos from gamma-ray bursts: propagation of cosmic rays in their host galaxies
Wang, Zi-Yi; Wang, Jun-Feng
2015-01-01
Gamma-ray bursts (GRBs) are proposed as candidate sources of ultra-high energy cosmic rays (UHECRs). We study the possibility that the PeV neutrinos recently observed by IceCube are produced by GRB cosmic rays interacting with the interstellar gas in the host galaxies. By studying the relation between the X-ray absorption column density N_H and the surface star-formation rate of GRB host galaxies, we find that N_H is a good indicator of the surface gas density of the host galaxies. Then we are able to calculate the neutrino production efficiency of CRs for GRBs with known N_H. We collect a sample of GRBs that have both measurements of N_H and accurate gamma-ray fluence, and attempt to calculate the accumulated neutrino flux based on the current knowledge about GRBs and their host galaxies. When the CR intensity produced by GRBs is normalized with the observed UHECR flux above $10^{19}{\\rm eV}$, the accumulated neutrino flux at PeV energies is estimated to be about $(0.3\\pm0.2)\\times10^{-8} \\rm{GeV\\ cm^{-2}\\ s... 10. Star formation in the hosts of GHz peaked spectrum and compact steep spectrum radio galaxies Labiano, A.; O'Dea, C. P.; Barthel, P. D.; Vries, W. H. de; Baum, S. A. 2007-01-01 Abstract: AIMS: Search for star formation regions in the hosts of potentially young radio galaxies (Gigahertz Peaked Spectrum and Compact Steep Spectrum sources). METHODS: Near-UV imaging with the Hubble Space Telescope Advanced Camera for Surveys.} RESULTS: We find near-UV light which could be the 11. The host galaxies of active galactic nuclei with powerful relativistic jets Olguín-Iglesias, A; Kotilainen, J K; Chavushyan, V; Tornikoski, M; Valtaoja, E; Añorve, C; Valdes, J; Carrasco, L 2016-01-01 We present deep Near-infrared (NIR) images of a sample of 19 intermediate-redshift ($0.310^{27}$WHz$^{-1}$), previously classified as flat-spectrum radio quasars. We also compile host galaxy and nuclear magnitudes for blazars from literature. The combined sample (this work and compilation) contains 100 radio-loud AGN with host galaxy detections and a broad range of radio luminosities$L_{1.4GHz} \\sim 10^{23.7} - 10^{28.3}$~WHz$^{-1}$, allowing us to divide our sample into high-luminosity blazars (HLBs) and low-luminosity blazars (LLBs). The host galaxies of our sample are bright and seem to follow the$\\mu_{e}$-$R_{eff}relation for ellipticals and bulges. The two populations of blazars show different behaviours in the \\mnuc - \\mbulge plane, where a statistically significant correlation is observed for HLBs. Although it may be affected by selection effects, this correlation suggests a close coupling between the accretion mode of the central supermassive black hole and its host galaxy, that could be interpre... 12. Star-formation in the host galaxies of radio-AGN Karouzos, Marios; Im, Myungshin; Malkan, Matthew 2013-01-01 There exist strong evidence supporting the co-evolution of central supermassive black holes and their host galaxies. It is however still unclear what the exact role of nuclear activity, in the form of accretion onto these supermassive black holes, in this co-evolution is. We use a rich multi-wavelength dataset available for the North Ecliptic Pole field, most notably surveyed by the AKARI satellite infrared telescope to study the host galaxy properties of AGN. In particular we are interested in investigating star-formation in the host galaxies of radio-AGN and the putative radio feedback mechanism, potentially responsible for the eventual quenching of star-formation. Using both broadband SED modeling and optical spectroscopy, we simultaneously study the nu- clear and host galaxy components of our sources, as a function of their radio luminosity, bolo- metric luminosity, and radio-loudness. Here we present preliminary results concerning the AGN content of the radio sources in this field, while offering tentati... 13. The metallicity and dust content of a redshift 5 gamma-ray burst host galaxy Sparre, M.; Krühler, T.; Fynbo, J. P. U.; Watson, D. J.; De Ugarte Postigo, A.; Hjorth, J.; Malesani, D. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen (Denmark); Hartoog, O. E.; Kaper, L. [Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam (Netherlands); Wiersema, K. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom); D' Elia, V. [INAF/Rome Astronomical Observatory, via Frascati 33, I-00040 Monteporzio Catone (Roma) (Italy); Zafar, T. [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching (Germany); Afonso, P. M. J. [Physics and Astronomy Department, American River College, 4700 College Oak Drive, Sacramento, CA 95841 (United States); Covino, S. [INAF, Osservatorio Astronomico di Brera, via E. Bianchi 46, I-23807 Merate (Italy); Flores, H. [Laboratoire GEPI, Observatoire de Paris, CNRS-UMR8111, Universite Paris Diderot 5 place Jules Janssen, F-92195 Meudon (France); Goldoni, P. [APC, Astroparticule et Cosmologie, Universite Paris Diderot, CNRS/IN2P3, CEA/Irfu, Observatoire de Paris, Sorbonne Paris Cité, 10, Rue Alice Domon et Léonie Duquet, F-75205 Paris, Cedex 13 (France); Greiner, J. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, D-85748 Garching (Germany); Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, IS-107 Reykjavik (Iceland); Klose, S. [Thüringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg (Germany); Levan, A. J., E-mail: [email protected] [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); and others 2014-04-20 Observations of the afterglows of long gamma-ray bursts (GRBs) allow the study of star-forming galaxies across most of cosmic history. Here we present observations of GRB 111008A, from which we can measure metallicity, chemical abundance patterns, dust-to-metals ratio (DTM), and extinction of the GRB host galaxy at z = 5.0. The host absorption system is a damped Lyα absorber with a very large neutral hydrogen column density of log N(H I)/cm{sup −2}=22.30±0.06 and a metallicity of [S/H] = –1.70 ± 0.10. It is the highest-redshift GRB with such a precise metallicity measurement. The presence of fine-structure lines confirms the z = 5.0 system as the GRB host galaxy and makes this the highest redshift where Fe II fine-structure lines have been detected. The afterglow is mildly reddened with A{sub V} = 0.11 ± 0.04 mag, and the host galaxy has a DTM that is consistent with being equal to or lower than typical values in the Local Group. 14. The Dependence of Type Ia Supernova Luminosities on their Host Galaxies Sullivan, M; Howell, D A; Neill, J D; Astier, P; Balland, C; Basa, S; Carlberg, R G; Fouchez, D; Guy, J; Hardin, D; Hook, I M; Pain, R; Palanque-Delabrouille, N; Perrett, K M; Pritchet, C J; Regnault, N; Rich, J; Ruhlmann-Kleider, V; Baumont, S; Hsiao, E; Kronborg, T; Lidman, C; Perlmutter, S; Walker, E S 2010-01-01 (Abridged) Precision cosmology with Type Ia supernovae (SNe Ia) makes use of the fact that SN Ia luminosities depend on their light-curve shapes and colours. Using Supernova Legacy Survey (SNLS) and other data, we show that there is an additional dependence on the global characteristics of their host galaxies: events of the same light-curve shape and colour are, on average, 0.08mag (~4.0sigma) brighter in massive host galaxies (presumably metal-rich) and galaxies with low specific star-formation rates (sSFR). SNe Ia in galaxies with a low sSFR also have a smaller slope ("beta") between their luminosities and colours with ~2.7sigma significance, and a smaller scatter on SN Ia Hubble diagrams (at 95% confidence), though the significance of these effects is dependent on the reddest SNe. SN Ia colours are similar between low-mass and high-mass hosts, leading us to interpret their luminosity differences as an intrinsic property of the SNe and not of some external factor such as dust. If the host stellar mass is in... 15. Cosmic Gamma-Ray Bursts, Their Afterglows, and Their Host Galaxies Hurley, K; Djorgovski, S G 2002-01-01 This is a review article for the book "Compact Stellar X-Ray Sources", Editors W. Lewin and M. van der Klis, to be published by Cambridge University Press in 2003. It covers the phenomenology of cosmic gamma-ray bursts, the theory of their afterglows, and the observations and interpretation of their host galaxies. 16. A COMPACT GROUP OF GALAXIES AT Z = 2.48 HOSTING AN AGN-DRIVEN OUTFLOW Shih, Hsin-Yi [Gemini Observatory, 670 N Aohoku Place, Hilo, HI 96720 (United States); Stockton, Alan, E-mail: [email protected], E-mail: [email protected] [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States) 2015-12-10 We present observations of a remarkable compact group of galaxies at z = 2.48. Four galaxies, all within 40 kpc of each other, surround a powerful high-redshift radio source. This group comprises two compact red passive galaxies and a pair of merging galaxies. One of the red galaxies, with an apparent stellar mass of 3.6 × 10{sup 11}M{sub ⊙} and an effective radius of 470 pc, is one of the most extreme examples of a massive quiescent compact galaxy found so far. One of the pair of merging galaxies hosts the active galactic nucleus (AGN) producing the large powerful radio structure. The merger is massive and enriched, consistent with the mass–metallicity relation expected at this redshift. Close to the merging nuclei, the emission lines exhibit broad and asymmetric profiles that suggest outflows powered either by a very young expanding radio jet or by AGN radiation. At ≳50 kpc from the system, we found a fainter extended-emission region that may be a part of a radio-jet-driven outflow. 17. Revisiting the Scaling Relations of Black Hole Masses and Host Galaxy Properties McConnell, Nicholas J 2012-01-01 New kinematic data and modeling efforts in the past few years have substantially expanded and revised dynamical measurements of black hole masses (Mbh) at the centers of nearby galaxies. Here we compile an updated sample of 72 black holes and their host galaxies, and present revised scaling relations between Mbh and stellar velocity dispersion (sigma), V-band luminosity (L), and bulge stellar mass (Mbulge), for different galaxy subsamples. Our best-fitting power law relations for the full galaxy sample are log(Mbh) = 8.33 + 5.57*log(sigma/200 kms), log(Mbh) = 9.23 + 1.11*log(L/10^{11} Lsun), and log(Mbh) = 8.46 + 1.05*log(Mbulge/10^{11} Msun). When the early- and late-type galaxies are fit separately, we obtain nearly identical slopes of ~5 for the Mbh-sigma relation but significantly different intercepts. Within early-type galaxies, we find a significantly higher intercept for galaxies with central core profiles than for those with central power-law profiles. At fixed sigma, our fits predict Mbh to be about ... 18. The Host Galaxy and Redshift of the Repeating Fast Radio Burst FRB 121102 Tendulkar, S. P.; Bassa, C. G.; Cordes, J. M.; Bower, G. C.; Law, C. J.; Chatterjee, S.; Adams, E. A. K.; Bogdanov, S.; Burke-Spolaor, S.; Butler, B. J.; Demorest, P.; Hessels, J. W. T.; Kaspi, V. M.; Lazio, T. J. W.; Maddox, N.; Marcote, B.; McLaughlin, M. A.; Paragi, Z.; Ransom, S. M.; Scholz, P.; Seymour, A.; Spitler, L. G.; van Langevelde, H. J.; Wharton, R. S. 2017-01-01 The precise localization of the repeating fast radio burst (FRB 121102) has provided the first unambiguous association (chance coincidence probability p ≲ 3 × 10‑4) of an FRB with an optical and persistent radio counterpart. We report on optical imaging and spectroscopy of the counterpart and find that it is an extended (0.″6–0.″8) object displaying prominent Balmer and [O iii] emission lines. Based on the spectrum and emission line ratios, we classify the counterpart as a low-metallicity, star-forming, mr‧ = 25.1 AB mag dwarf galaxy at a redshift of z = 0.19273(8), corresponding to a luminosity distance of 972 Mpc. From the angular size, the redshift, and luminosity, we estimate the host galaxy to have a diameter ≲4 kpc and a stellar mass of M* ∼ (4–7) × 107 M⊙, assuming a mass-to-light ratio between 2 to 3 M⊙ L⊙‑1. Based on the Hα flux, we estimate the star formation rate of the host to be 0.4 M⊙ yr‑1 and a substantial host dispersion measure (DM) depth ≲324 pc cm‑3. The net DM contribution of the host galaxy to FRB 121102 is likely to be lower than this value depending on geometrical factors. We show that the persistent radio source at FRB 121102’s location reported by Marcote et al. is offset from the galaxy’s center of light by ∼200 mas and the host galaxy does not show optical signatures for AGN activity. If FRB 121102 is typical of the wider FRB population and if future interferometric localizations preferentially find them in dwarf galaxies with low metallicities and prominent emission lines, they would share such a preference with long gamma-ray bursts and superluminous supernovae. 19. Investigating the AGN-Galaxy Interaction Relationship by Examining the Color and Morphology Measurements of Real and Simulated AGN Host Galaxies Pierce, Christina M. 2009-01-01 UV-optical colors provide a clear distinction between quiescent galaxies and those undergoing star formation. Galaxy morphology measurements, such as the Gini coefficient, M20, concentration, asymmetry, and the Sersic index, allow identification of interacting galaxies and separation of non-interacting galaxies into bulge or disk-dominated systems. Thus, one can use the colors and morphologies of AGN host galaxies to probe the predicted relationship between galaxy interactions and significant black hole growth (an AGN stage). However, due to the UV excess observed in many AGNs (particularly quasars and Seyfert 1 galaxies) and the potentially significant optical contribution from AGNs that are not heavily obscured, one must exercise caution when interpreting the results from color and morphology measurements of AGN host galaxies. With this in mind, we created a set of simulated AGNs to test the reliability of color and morphology measurements of AGN host galaxies. The results were compared to observations of AGN host galaxies at z 1 from the All-wavelength Extended Groth Strip International Survey (AEGIS). Our observed results reveal a population of X-ray luminous AGN hosts that appear to have green UV-optical colors, indicative of recent star-formation, and a largely disk-dominated profile, suggesting a bulge that is not yet fully developed. Comparison with results from our simulated AGNs suggest that at least some of the observational results are not likely to be due to color or morphological contamination from the presence of an AGN. Therefore, the observed AGN hosts seem to represent a real population that may be going through a transition phase, during which significant star-formation has recently ceased, but for which the black hole remains quite luminous. 20. Optical imaging of the host galaxies of X-ray selected BL Lacertae objects Falomo, R 1999-01-01 We investigate the properties of the host galaxies of X-ray selected (high frequency peaked) BL Lac objects using a large and homogeneous data set of high spatial resolution R-band observations of 52 BL Lacs in the EMSS and Slew samples. The redshift distribution of the BL Lacs ranges from z = 0.04 to z>0.7, with average and median redshifts z = 0.26 and z = 0.24, respectively. Eight objects are at unknown redshift. We are able to resolve 45 objects out of the 52 BL Lacs. For all the well-resolved sources, we find the host to be a luminous elliptical galaxy. In a few cases a disk is not ruled out but an elliptical model is still preferred. The average absolute magnitude of the host galaxies is = -23.9+-0.6, while the average scale length of the host is = 9+-5 kpc. There is no difference in the host properties between the EMSS and Slew samples. We find a good agreement between the results derived by the surveys of Wurtz et al. (ground-based data) and Urry et al. (HST data), and by our new deeper imaging. The... 1. The Dependence of Cluster Galaxy Properties on the Central Entropy of their Host Cluster Kim, Jae-Woo; Ko, Jongwan; Hwang, Ho Seong; Edge, Alastair C.; Lee, Joon Hyeop; Lee, Jong Chul; Jeong, Hyunjin 2017-02-01 We present a study of the connection between brightest cluster galaxies (BCGs) and their host galaxy clusters. Using galaxy clusters at 0.1Entropy Profile Tables (ACCEPT), we confirm that BCGs in low central entropy clusters are well aligned with the X-ray center. Additionally, the magnitude difference between BCG and the second brightest galaxy also correlates with the central entropy of the intracluster medium. From the red-sequence (RS) galaxies, we cannot find significant dependence of RS color scatter and stellar population on the central entropy of the intracluster medium of their host cluster. However, BCGs in low-entropy clusters are systematically less massive than those in high-entropy clusters, although this is dependent on the method used to derive the stellar mass of BCGs. In contrast, the stellar velocity dispersion of BCGs shows no dependence on BCG activity and cluster central entropy. This implies that the potential of the BCG is established earlier and the activity leading to optical emission lines is dictated by the properties of the intracluster medium in the cluster core. 2. ALFALFA HI Data Stacking II. HI content of the host galaxies of AGN Fabello, S; Catinella, B; Giovanelli, R; Haynes, M P; Heckman, T M; Schiminovich, D 2011-01-01 We use a stacking technique to measure the average HI content of a volume-limited sample of 1871 AGN host galaxies from a parent sample of galaxies selected from the SDSS and GALEX imaging surveys with stellar masses greater than 10^10 M_sun and redshifts in the range 0.025galaxies correlates most strongly with the combination of optical/UV colour and stellar surface mass density. We therefore build a control sample of non-AGN matched to the AGN hosts in these two properties. We study trends in HI gas mass fraction (M(HI)/M_*), where M_* is the stellar mass) as a function of black hole accretion rate indicator L[OIII]/M(BH). We find no significant difference in HI content between AGN and control samples at all values of black hole accretion rate probed by the galaxies in our sample. This indicates that AGN do not influence the large-scale gaseous properties of galaxie... 3. Constraining the properties of AGN host galaxies with Spectral Energy Distribution modeling Ciesla, L; Georgakakis, A; Bernhard, E; Mitchell, P D; Buat, V; Elbaz, D; Floc'h, E Le; Lacey, C G; Magdis, G E; Xilouris, M 2015-01-01 [abridged] We use the latest release of CIGALE, a galaxy SED fitting model relying on energy balance, to study the influence of an AGN in estimating both the SFR and stellar mass in galaxies, as well as the contribution of the AGN to the power output of the host. Using the galaxy formation SAM GALFORM, we create mock galaxy SEDs using realistic star formation histories (SFH) and add an AGN of Type 1, Type 2, or intermediate type whose contribution to the bolometric luminosity can be variable. We perform an SED fitting of these catalogues with CIGALE assuming three different SFHs: a single- and double-exponentially-decreasing, and a delayed SFH. Constraining thecontribution of an AGN to the LIR (fracAGN) is very challenging for fracAGN<20%, with uncertainties of ~5-30% for higher fractions depending on the AGN type, while FIR and sub-mm are essential. The AGN power has an impact on the estimation ofM_*$in Type 1 and intermediate type AGNs but has no effect for galaxies hosting Type 2 AGNs. We find that i... 4. Extreme Host Galaxy Growth in Powerful Early-epoch Radio Galaxies Barthel, Peter; Haas, Martin; Leipski, Christian; Wilkes, Belinda 2012-01-01 During the first half of the universe's life, a heyday of star formation must have occurred because many massive galaxies are in place after that epoch in cosmic history. Our observations with the revolutionary Herschel Space Observatory reveal vigorous optically obscured star formation in the ultra 5. The Host Galaxies of Fast-Ejecta Core-Collapse Supernovae Kelly, Patrick L.; Filippenko, Alexei V.; Modjaz, Maryam; Kocevski, Daniel 2014-01-01 Spectra of broad-lined Type Ic supernovae (SN Ic-BL), the only kind of SN observed at the locations of long-duration gamma-ray bursts (LGRBs), exhibit wide features indicative of high ejecta velocities ((is) approximately 0.1c). We study the host galaxies of a sample of 245 low-redshift (z (is) less than 0.2) core-collapse SN, including 17 SN Ic-BL, discovered by galaxy-untargeted searches, and 15 optically luminous and dust-obscured z (is) less than 1.2 LGRBs. We show that, in comparison with SDSS galaxies having similar stellar masses, the hosts of low-redshift SN Ic- BL and z (is) is less than 1.2 LGRBs have high stellar-mass and star-formation-rate densities. Core-collapse SN having typical ejecta velocities, in contrast, show no preference for such galaxies. Moreover, we find that the hosts of SN Ic-BL, unlike those of SN Ib/Ic and SN II, exhibit high gas velocity dispersions for their stellar masses. The patterns likely reflect variations among star-forming environments, and suggest that LGRBs can be used as probes of conditions in high-redshift galaxies. They may be caused by efficient formation of massive binary progenitors systems in densely star-forming regions, or, less probably, a higher fraction of stars created with the initial masses required for a SN Ic-BL or LGRB. Finally, we show that the preference of SN Ic-BL and LGRBs for galaxies with high stellar-mass and star-formation-rate densities cannot be attributed to a preference for low metal abundances but must reflect the influence of a separate environmental factor. 6. Accreting SMBHs in the COSMOS field and the connection to their host galaxies Bongiorno, A; Brusa, M; Magnelli, B; Salvato, M; Mignoli, M; Zamorani, G; Fiore, F; Rosario, D; Mainieri, V; Comastri, A; Vignali, C; Balestra, I; Bardelli, S; Berta, S; Civano, F; Kampczyk, P; Floc'h, E Le; Lusso, E; Lutz, D; Pozzetti, L; Pozzi, F; Riguccini, L; Shankar, F; Silverman, J 2012-01-01 Using the wide multi-band photometry available in the COSMOS field we explore the host galaxy properties of a large sample of Active Galactic Nuclei (AGN) obtained by combining X-ray and optical spectroscopic selections. Based on a careful study of their Spectral Energy Distribution (SED), which has been parametrized using a 2-component (AGN+galaxy) model fit, we derived dust-corrected rest-frame magnitudes, colors, stellar masses and star formation rates (SFRs). We find that AGN hosts span a large range of stellar masses and SFRs. No color-bimodality is seen at any redshift in the AGN hosts, which are found to be mainly massive, red galaxies. Once accounting for the color-mass degeneracy in well defined mass-matched samples, we find a residual marginal enhancement of AGN incidence in redder galaxies with lower specific star formation rates, and we argue that this result might emerge because of our ability to properly account for AGN light contamination and dust extinction. Interestingly, we find that the pro... 7. The dark nature of GRB 130528A and its host galaxy Jeong, S; Bremer, M; Winters, J M; Gorosabel, J; Guziy, S; Pandey, S B; Jelínek, M; Sánchez-Ramírez, R; Sokolov, Ilya V; Orekhova, N V; Moskvitin, A S; Tello, J C; Cunniffe, R; Lara-Gil, O; Pérez-Ramírez, D; Bai, J; Fan, Y; Wang, C; Park, I H 2014-01-01 We study the dark nature of GRB 130528A via the multi-wavelength observations and conclude that the main reason for this is the local extinction inside the host galaxy. Automatic observations were performed at BOOTES-4/MET robotic telescope. We also triggered Target of Opportunity (ToO) observation at the OSN, IRAM PdBI and the GTC+OSIRIS. The host galaxy photometric observations in optical to near-infrared (nIR) wavelengths were achieved through ground large aperture telescopes, such as the 10.4m GTC, the 4.2m WHT, and the 6m BTA telescope. Based on these observations, a spectral energy distributions (SED) model for the host galaxy and afterglow was constructed. We confirmed a clearly fading mm source within the XRT error circle thanks to our millimetre observations at PdBI while no credible optical source was found in early observation at the BOOTES-4/MET and 1.5m OSN telescopes. Spectroscopic observation of this galaxy at the GTC showed faint [OII] 3727\\{AA} emission line at a redshift of 1.250+/-0.001 imp... 8. Long Gamma-Ray Bursts and Their Host Galaxies at High Redshift Lapi, A; Bosnjak, Z; Celotti, A; Bressan, A; Granato, G L; Danese, L 2008-01-01 Motivated by the recent observational and theoretical evidence that long Gamma-Ray Bursts (GRBs) are likely associated with low metallicity, rapidly rotating massive stars, we examine the cosmological star formation rate (SFR) below a critical metallicity Z_crit~Z_sun/10 - Z_sun/5, to estimate the event rate of high-redshift long GRB progenitors. To this purpose, we exploit a galaxy formation scenario already successfully tested on a wealth of observational data on (proto)spheroids, Lyman break galaxies, Lyman alpha emitters, submm galaxies, quasars, and local early-type galaxies. We find that the predicted rate of long GRBs amounts to about 300 events/yr/sr, of which about 30 per cent occur at z>~6. Correspondingly, the GRB number counts well agree with the bright SWIFT data, without the need for an intrinsic luminosity evolution. Moreover, the above framework enables us to predict properties of the GRB host galaxies. Most GRBs are associated with low mass galaxy halos M_H~10^12 M_sun have larger extinction ... 9. On the mass-metallicity relation, velocity dispersion and gravitational well depth of GRB host galaxies Arabsalmani, Maryam; Møller, Palle; Fynbo, Johan P. U.; 2016-01-01 away from the metallicity in the centre of the galaxy, second the path of the sightline through different parts of the potential well of the dark matter halo will cause different velocity fields to be sampled. We report evidence suggesting that this second effect may have been detected....... the same underlying population. GRB host galaxies and QSO-DLAs are found to have different impact parameter distributions and we briefly discuss how this may affect statistical samples. The impact parameter distribution has two effects. First any metallicity gradient will shift the measured metallicity... 10. The Discovery of Host Galaxy HI Absorption in CTA 21 Salter, C J; Minchin, R; Ghosh, T; Chandola, Y 2010-01-01 We report the discovery of HI 21-cm absorption towards the well-studied GHz Peaked-Spectrum source CTA 21 (4C 16.09) using the Arecibo Telescope on 2009 September 20 and 21. Recently, the frequency band between 700 and 800 MHz was temporarily opened up to radio astronomy when US TV stations were mandated to switch from analog to digital transmissions, with new frequency allocations. The redshifted HI frequency for CTA 21 falls within this band. CTA 21 has a complex radio structure on a range of scales. The innermost prominent components are separated by ~12 mas while weak diffuse emission extends for up to ~300 mas. The HI absorption profile that we find has two main components, one narrow, the other wider and blue-shifted. The total HI column density is 7.9 x 10^20 cm^-2, assuming a covering factor of unity and a spin temperature of 100 K. This HI absorption confirms the recently determined optical redshift of this faint galaxy of z ~ 0.907. We discuss this new detection in the light of HI absorption studies... 11. Scaling Relations Between Warm Galactic Outflows and Their Host Galaxies Chisholm, John; Leitherer, Claus; Chen, Yanmei; Wofford, Aida; Lundgren, Britt 2014-01-01 We report on a sample of 51 nearby, star-forming galaxies observed with the Cosmic Origin Spectrograph on the Hubble Space Telescope. We calculate Si II kinematics and densities arising from warm gas entrained in galactic outflows. We use multi-wavelength ancillary data to estimate stellar masses (M$_\\ast$), star-formation rates (SFR), and morphologies. We derive significant correlations between outflow velocity and SFR$^{\\sim 0.1}$, M$_\\ast^{\\sim 0.1}$and v$_\\text{circ}^{\\sim 1/2}$. Some mergers drive outflows faster than these relations prescribe, launching the outflow faster than the escape velocity. Calculations of the mass outflow rate reveal strong scaling with SFR$^{\\sim 1/2}$and M$_\\ast^{\\sim 1/2}$. Additionally, mass-loading efficiency factors (mass outflow rate divided by SFR) scale approximately as M$_\\ast^{-1/2}$. Both the outflow velocity and mass-loading scaling suggest that these outflows are powered by supernovae, with only 0.7% of the total supernovae energy converted into the kinetic energ... 12. LONG GRBs ARE METALLICITY-BIASED TRACERS OF STAR FORMATION: EVIDENCE FROM HOST GALAXIES AND REDSHIFT DISTRIBUTION Wang, F. Y.; Dai, Z. G., E-mail: [email protected], E-mail: [email protected] [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China) 2014-07-01 We investigate the mass distribution of long gamma-ray burst (GRB) host galaxies and the redshift distribution of long GRBs by considering that long GRBs occur in low-metallicity environments. We calculate the upper limit on the stellar mass of a galaxy which can produce long GRBs by utilizing the mass-metallicity (M-Z) relation of galaxies. After comparing with the observed GRB host galaxies masses, we find that the observed GRB host galaxy masses can fit the predicted masses well if GRBs occur in low-metallicity 12 + log (O/H){sub KK04} < 8.7. GRB host galaxies have low metallicity, low mass, and high star formation rate compared with galaxies of seventh data release of the Sloan Digital Sky Survey. We also study the cumulative redshift distribution of the latest Swift long GRBs by adding dark GRBs and 10 new GRBs redshifts from the TOUGH survey. The observed discrepancy between the GRB rate and the star formation history can be reconciled by considering that GRBs tend to occur in low-metallicity galaxies with 12 + log (O/H){sub KK04} < 8.7. We conclude that the metallicity cutoff that can produce long GRBs is about 12 + log (O/H){sub KK04} < 8.7 from the host mass distribution and redshift distribution. 13. Morphologies of z~0.7 AGN Host Galaxies in CANDELS: No trend of merger incidence with AGN luminosity Villforth, C; Rosario, D J; Santini, P; McGrath, E J; van der Wel, A; Chang, Y -Y; Guo, Yicheng; Dahlen, T; Bell, E F; Conselice, C J; Croton, D; Dekel, A; Faber, S M; Grogin, N; Hamilton, T; Hopkins, P F; Juneau, S; Kartaltepe, J; Kocevski, D; Koekemoer, A; Koo, D C; Lotz, J; McIntosh, D; Mozena, M; Somerville, R; Wild, V 2014-01-01 The processes that trigger Active Galactic Nuclei (AGN) remain poorly understood. While lower luminosity AGN may be triggered by minor disturbances to the host galaxy, stronger disturbances are likely required to trigger luminous AGN. Major wet mergers of galaxies are ideal environments for AGN triggering since they provide large gas supplies and galaxy scale torques. There is however little observational evidence for a strong connection between AGN and major mergers. We analyse the morphological properties of AGN host galaxies as a function of AGN and host galaxy luminosity and compare them to a carefully matched sample of control galaxies. AGN are X-ray selected in the redshift range 0.5 < z < 0.8 and have luminosities 41 < log(L_X [erg/s]) < 44.5. 'Fake AGN' are simulated in the control galaxies by adding point sources with the magnitude of the matched AGN. We find that AGN host and control galaxies have comparable assymetries, Sersic indices and ellipticities at restframe ~950nm. AGN host gala... 14. Supernovae and their host galaxies - III. The impact of bars and bulges on the radial distribution of supernovae in disc galaxies Hakobyan, A A; Barkhudaryan, L V; Mamon, G A; Kunth, D; Petrosian, A R; Adibekyan, V; Aramyan, L S; Turatto, M 2016-01-01 We present an analysis of the impact of bars and bulges on the radial distributions of the different types of supernovae (SNe) in the stellar discs of host galaxies with various morphologies. We use a well-defined sample of 500 nearby (< 100 Mpc) SNe and their low-inclined (i < 60 deg) and morphologically non-disturbed S0-Sm host galaxies from the Sloan Digital Sky Survey. We find that in Sa-Sm galaxies, all core-collapse (CC) and vast majority of SNe Ia belong to the disc, rather than the bulge component. The radial distribution of SNe Ia in S0-S0/a galaxies is inconsistent with their distribution in Sa-Sm hosts, which is probably due to the contribution of the outer bulge SNe Ia in S0-S0/a galaxies. In Sa-Sbc galaxies, the radial distribution of CC SNe in barred hosts is inconsistent with that in unbarred ones, while the distributions of SNe Ia are not significantly different. At the same time, the radial distributions of both types of SNe in Sc-Sm galaxies are not affected by bars. We propose that th... 15. AGN host galaxy mass function in COSMOS: is AGN feedback responsible for the mass-quenching of galaxies? Bongiorno, A; Merloni, A; Zamorani, G; Ilbert, O; La Franca, F; Peng, Y; Piconcelli, E; Mainieri, V; Silverman, J D; Brusa, M; Fiore, F; Salvato, M; Scoville, N 2016-01-01 We investigate the role of supermassive black holes in the global context of galaxy evolution by measuring the host galaxy stellar mass function (HGMF) and the specific accretion rate i.e., lambda_SAR, distribution function (SARDF) up to z~2.5 with ~1000 X-ray selected AGN from XMM-COSMOS. Using a maximum likelihood approach, we jointly fit the stellar mass function and specific accretion rate distribution function, with the X-ray luminosity function as an additional constraint. Our best fit model characterizes the SARDF as a double power-law with mass dependent but redshift independent break whose low lambda_SAR slope flattens with increasing redshift while the normalization increases. This implies that, for a given stellar mass, higher lambda_SAR objects have a peak in their space density at earlier epoch compared to the lower lambda_SAR ones, following and mimicking the well known AGN cosmic downsizing as observed in the AGN luminosity function. The mass function of active galaxies is described by a Schech... 16. The host galaxy of the gamma-ray narrow-line Seyfert 1 galaxy 1H 0323+342 León Tavares, J.; Chavushyan, V.; Puerari, I.; Patiño-Alvarez, V.; Carramiñana, A.; Carrasco, L.; Guichard, J.; Olguín-Iglesias, A.; Valdes, J. [Instituto Nacional de Astrofísica Óptica y Electrónica (INAOE), Apartado Postal 51 y 216, 72000 Puebla (Mexico); Kotilainen, J. [Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Väisäläntie 20, FI-21500 Piikkiö (Finland); Añorve, C. [Facultad de Ciencias de la Tierra y del Espacio (FACITE) de la Universidad Autónoma de Sinaloa, Blvd. de la Americas y Av. Universitarios S/N, Ciudad Universitaria, C.P. 80010, Culiacán Sinaloa (Mexico); Cruz-González, I. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Ap. 70-264, 04510 DF (Mexico); Antón, S. [Instituto de Astrofísica de Andalucía-CSIC, E-18008 Granada (Spain); Karhunen, K.; Sanghvi, J., E-mail: [email protected] [Tuorla Observatory, Department of Physics and Astronomy, University of Turku, FI-20100 Turku (Finland) 2014-11-01 We present optical and near-infrared (NIR) imaging data of the radio-loud, narrow-line Seyfert 1 galaxy 1H 0323+342, which shows intense and variable gamma-ray activity discovered by the Fermi satellite with the Large Area Telescope. Near-infrared and optical images are used to investigate the structural properties of the host galaxy of 1H 0323+342; this together with optical spectroscopy allows us to examine its black hole mass. Based on two-dimensional (2D) multiwavelength surface-brightness modeling, we find that statistically, the best model fit is a combination of a nuclear component and a Sérsic profile (n ∼ 2.8). However, the presence of a disk component (with a small bulge n ∼ 1.2) also remains a possibility and cannot be ruled out with the present data. Although at first glance a spiral-arm-like structure is revealed in our images, a 2D Fourier analysis of the imagery suggests that this structure corresponds to an asymmetric ring, likely associated with a recent violent dynamical interaction. We discuss our results in the context of relativistic jet production and galaxy evolution. 17. Supermassive black holes and their host galaxies. II. The correlation with near-infrared luminosity revisited Läsker, Ronald; Van de Ven, Glenn [Max-Planck Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Ferrarese, Laura [NRC Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E2E7 (Canada); Shankar, Francesco, E-mail: [email protected] [GEPI Observatoire de Paris, CNRS, Univ. Paris Diderot, 5 Place Jules Janssen, F-92195 Meudon (France) 2014-01-01 We present an investigation of the scaling relations between supermassive black hole (SMBH) masses, M {sub •}, and their host galaxies' K-band bulge (L {sub bul}) and total (L {sub tot}) luminosities. The wide-field WIRCam imager at the Canada-France-Hawaii-Telescope was used to obtain the deepest and highest resolution near-infrared images available for a sample of 35 galaxies with securely measured M {sub •}, selected irrespective of Hubble type. For each galaxy, we derive bulge and total magnitudes using a two-dimensional image decomposition code that allows us to account, if necessary, for large- and small-scale disks, cores, bars, nuclei, rings, envelopes, and spiral arms. We find that the present-day M {sub •}-L {sub bul} and M {sub •}-L {sub tot} relations have consistent intrinsic scatter, suggesting that M {sub •} correlates equally well with bulge and total luminosity of the host. Our analysis provides only mild evidence of a decreased scatter if the fit is restricted to elliptical galaxies. The log-slopes of the M {sub •}-L {sub bul} and M {sub •}-L {sub tot} relations are 0.75 ± 0.10 and 0.92 ± 0.14, respectively. However, while the slope of the M {sub •}-L {sub bul} relation depends on the detail of the image decomposition, the characterization of M {sub •}-L {sub tot} does not. Given the difficulties and ambiguities of decomposing galaxy images into separate components, our results indicate that L {sub tot} is more suitable as a tracer of SMBH mass than L {sub bul}, and that the M {sub •}-L {sub tot} relation should be used when studying the co-evolution of SMBHs and galaxies. 18. Magellan LDSS3 emission confirmation of galaxies hosting metal-rich Lyman-alpha absorption systems Straka, Lorrie A; York, Donald G; Bowen, David V; Florian, Michael; Kulkarni, Varsha P; Lundgren, Britt; Peroux, Celine 2015-01-01 Using the Low Dispersion Survey Spectrograph 3 at the Magellan II Clay Telescope in Chile, we target candidate absorption host galaxies detected in deep optical imaging (reaching limiting apparent magnitudes of 23.0-26.5 in g; r; i; and z filters) in the fields of three QSOs, each of which shows the presence of high metallicity, strong NHI absorption systems in their spectra (Q0826-2230: zabs=0.9110, Q1323-0021: zabs = 0.7160, Q1436-0051: zabs = 0.7377; 0.9281). We confirm host galaxies at redshifts 0.7387, 0.7401, and 0.9286 for two out of four of the Ly-alpha absorption systems. For these systems, we are able to determine the SFRs; impact parameters (known from previous imaging detections); the velocity shift between the absorption and emission redshifts; and, for one system, also the emission metallicity. Based on previous photometry, we find these galaxies have L>L*. The SFRs for these galaxies, based on [O II] emission, are in the range 11-25 M_sol/yr (uncorrected for dust), while the impact parameters l... 19. A tale of two feedbacks: star-formation in the host galaxies of radio-AGN Karouzos, Marios; Trichas, Markos; Ruiz, Angel; Goto, Tomo; Malkan, Matt; Jeon, Yiseul; Kim, Ji Hoon; Lee, Hyung Mok; Kim, Seongjin; Oi, Nagisa; Matsuhara, Hideo; Takagi, Toshinobu; Murata, Kazumi; Wada, Takehiko; Wada, Kensuke; Shim, Hyunjin; Hanami, Hitoshi; Serheant, Stephen; White, Glenn J; Pearson, Crhis; Ohyama, Youichi 2013-01-01 Several lines of argument support the existence of a link between activity at the nuclei of galaxies, in the form of an accreting supermassive black hole, and star-formation activity in these galaxies. The exact nature of this link is still under debate. Radio jets have long been argued to be an ideal mechanism that allows AGN to interact with their host galaxy and regulate star-formation. In this context, we are using a sample of radio sources in the North Ecliptic Pole (NEP) field to study the nature of the putative link between AGN activity and star-formation. This is done by means of spectral energy distribution (SED) fitting. We use the excellent spectral coverage of the AKARI infrared space telescope together with the rich ancillary data available in the NEP to build SEDs extending from UV to far-IR wavelengths. Through SED fitting we constrain both the AGN and host galaxy components. We find a significant AGN component in our sample of relatively faint radio-sources ($<$mJy), that increases in power... 20. Co-evolution of nuclear star clusters, massive black holes and their host galaxies Antonini, Fabio; Silk, Joseph 2015-01-01 Studying how nuclear star clusters (NSCs) form and how they are related to the growth of the central massive black holes (MBHs) and their host galaxies is fundamental for our understanding of the evolution of galaxies and the processes that have shaped their central structures. We present the results of a semi-analytical galaxy formation model that follows the evolution of dark matter halos along merger trees, as well as that of the baryonic components. This model allows us to study the evolution of NSCs in a cosmological context, by taking into account the growth of NSCs due to both dynamical friction-driven migration of stellar clusters and star formation triggered by infalling gas, while also accounting for dynamical heating from (binary) MBHs. We find that in-situ star formation contributes a significant fraction (up to ~40%) of the total mass of NSCs in our model. Both NSC growth through in-situ star formation and through star cluster migration are found to generate NSC -- host galaxy scaling correlation... 1. Herschel observed Stripe 82 quasars and their host galaxies: connections between the AGN activity and the host galaxy star formation Dong, Xiaoyi 2016-01-01 In this work, we present a study of 207 quasars selected from the Sloan Digital Sky Survey quasar catalogs and the Herschel Stripe 82 survey. Quasars within this sample are high luminosity quasars with a mean bolometric luminosity of$10^{46.4}$erg s$^{-1}$. The redshift range of this sample is within$z<4$, with a mean value of$1.5\\pm0.78$. Because we only selected quasars that have been detected in all three Herschel-SPIRE bands, the quasar sample is complete yet highly biased. Based on the multi-wavelength photometric observation data, we conducted a spectral energy distribution (SED) fitting through UV to FIR. Parameters such as active galactic nucleus (AGN) luminosity, FIR luminosity, stellar mass, as well as many other AGN and galaxy properties are deduced from the SED fitting results. The mean star formation rate (SFR) of the sample is 419$M_{\\odot}$yr$^{-1}$and the mean gas mass is$\\sim 10^{11.3}M_{\\odot}$. All these results point to an IR luminous quasar system. Comparing with star format... 2. Deep Ly alpha imaging of two z=2.04 GRB host galaxy fields Fynbo, J.P.U.; Møller, Per; Thomsen, Bente 2002-01-01 We report on the results of deep narrow-band Lyalpha and broad-band U and I imaging of the fields of two Gamma-Ray bursts at redshift z = 2.04 (GRB 000301C and GRB 000926). We find that the host galaxy of GRB 000926 is an extended (more than 2 arcsec), strong Lyalpha emitter with a rest-frame equ......We report on the results of deep narrow-band Lyalpha and broad-band U and I imaging of the fields of two Gamma-Ray bursts at redshift z = 2.04 (GRB 000301C and GRB 000926). We find that the host galaxy of GRB 000926 is an extended (more than 2 arcsec), strong Lyalpha emitter with a rest... 3. Deep Ly alpha imaging of two z=2.04 GRB host galaxy fields Fynbo, J.P.U.; Møller, Per; Thomsen, Bente 2002-01-01 We report on the results of deep narrow-band Lyalpha and broad-band U and I imaging of the fields of two Gamma-Ray bursts at redshift z = 2.04 (GRB 000301C and GRB 000926). We find that the host galaxy of GRB 000926 is an extended (more than 2 arcsec), strong Lyalpha emitter with a rest-frame equ......We report on the results of deep narrow-band Lyalpha and broad-band U and I imaging of the fields of two Gamma-Ray bursts at redshift z = 2.04 (GRB 000301C and GRB 000926). We find that the host galaxy of GRB 000926 is an extended (more than 2 arcsec), strong Lyalpha emitter with a rest... 4. The metallicity and dust content of a redshift 5 gamma-ray burst host galaxy Sparre, M.; Hartoog, O. E.; Krühler, T. 2014-01-01 Observations of the afterglows of long gamma-ray bursts (GRBs) allow the study of star-forming galaxies across most of cosmic history. Here we present observations of GRB 111008A from which we can measure metallicity, chemical abundance patterns, dust-to-metals ratio and extinction of the GRB host...... galaxy at z=5.0. The host absorption system is a damped Lyman-alpha absorber (DLA) with a very large neutral hydrogen column density of log N(HI)/cm^(-2) = 22.30 +/- 0.06, and a metallicity of [S/H]= -1.70 +/- 0.10. It is the highest redshift GRB with such a precise metallicity measurement. The presence... 5. VizieR Online Data Catalog: Host galaxies of Superluminous Supernovae (Angus+, 2016) Angus, C. R.; Levan, A. J.; Perley, D. A.; Tanvir, N. R.; Lyman, J. D.; Stanway, E. R.; Fruchter, A. S. 2016-11-01 Here we use nIR and rest-frame UV observations of a sample of 21 SLSN host galaxies, within a redshift range of 0.019 SCP 06F6). This HST sample (programme GO-13025; PI: Levan) comprised 21 targets, based on the sample of Neill et al. (2011ApJ...727...15N), supplemented with luminous SNe from the literature (up to 2012 Jan). (6 data files). 6. Systematic Effects in Type-1a Supernovae Surveys from Host Galaxy Spectra Strauss, Michael A. [Princeton University 2013-08-23 The physical relation between the properties of Type Ia supernovae and their host galaxies is investigated. Such supernovae are used to constrain the properties of dark energy, making it crucial to understand their physical properties and to check for systematic effects relating to the stellar populations of the progenitor stars from which these supernovae arose. This grant found strong evidence for two distinct populations of supernovae, and correlations between the progenitor stellar populations and the nature of the supernova light curves. 7. Rapid Coeval Black Hole and Host Galaxy Growth in MRC 1138-262: The Hungry Spider Seymour, N; De Breuck, C; Barthel, P; Coia, D; Conversi, L; Dannerbauer, H; Dey, A; Dickinson, M; Drouart, G; Galametz, A; Greve, T R; Haas, M; Hatch, N; Ibar, E; Ivison, R; Jarvis, M; Kovacs, A; Kurk, J; Lehnert, M; Miley, G; Nesvadba, N; Rawlings, J I; Rettura, A; Rottgering, H; Rocca-Volmerange, B; Sanchez-Portal, M; Santos, J S; Stern, D; Stevens, J; Valtchanov, I; Vernet, J; Wylezalek, D 2012-01-01 We present a detailed study of the infrared spectral energy distribution of the high-redshift radio galaxy MRC 1138-26 at z = 2.156, also known as the Spiderweb Galaxy. By combining photometry from Spitzer, Herschel and LABOCA we fit the rest-frame 5-300 um emission using a two component, starburst and active galactic nucleus (AGN), model. The total infrared (8 - 1000 um) luminosity of this galaxy is (1.97+/-0.28)x10^13 Lsun with (1.17+/-0.27) and (0.79+/-0.09)x10^13 Lsun due to the AGN and starburst components respectively. The high derived AGN accretion rate of \\sim20% Eddington, and the measured star formation rate (SFR) of 1390pm150 Msun/yr, suggest that this massive system is in a special phase of rapid central black hole and host galaxy growth, likely caused by a gas rich merger in a dense environment. The accretion rate is sufficient to power both the jets and the previously observed large outflow. The high SFR and strong outflow suggest this galaxy could potentially exhaust its fuel for stellar growth... 8. Dynamical friction and scratches of orbiting satellite galaxies on host systems Ogiya, Go 2015-01-01 We study the dynamical response of extended systems, hosts, to smaller systems, satellites, orbiting around the hosts using extremely high-resolution N-body simulations with up to one billion particles. This situation corresponds to minor mergers which are ubiquitous in the scenario of hierarchical structure formation in the universe. According to Chandrasekhar (1943), satellites create density wakes along the orbit and the wakes cause a deceleration force on satellites, i.e. dynamical friction. This study proposes an analytical model to predict the dynamical response of hosts in the density distribution and finds not only traditional wakes but also mirror images of over- and underdensities centered on the host. Controlled N-body simulations with high resolutions verify the predictions of the analytical model directly. We apply our analytical model to the expected dynamical response of nearby interacting galaxy pairs, the Milky Way - Large Magellanic Cloud system and the M31 - M33 system. 9. Dynamical friction and scratches of orbiting satellite galaxies on host systems Ogiya, Go; Burkert, Andreas 2016-04-01 We study the dynamical response of extended systems, hosts, to smaller systems, satellites, orbiting around the hosts using extremely high-resolution N-body simulations with up to one billion particles. This situation corresponds to minor mergers which are ubiquitous in the scenario of hierarchical structure formation in the universe. According to Chandrasekhar, satellites create density wakes along the orbit and the wakes cause a deceleration force on satellites, i.e. dynamical friction. This study proposes an analytical model to predict the dynamical response of hosts as reflected in their density distribution and finds not only traditional wakes but also mirror images of over- and underdensities centred on the host. Our controlled N-body simulations with high resolutions verify the predictions of the analytical model. We apply our analytical model to the expected dynamical response of nearby interacting galaxy pairs, the Milky Way-Large Magellanic Cloud system and the M31-M33 system. 10. DEMOGRAPHICS OF THE GALAXIES HOSTING SHORT-DURATION GAMMA-RAY BURSTS Fong, W.; Berger, E.; Chornock, R.; Margutti, R.; Czekala, I.; Zauderer, B. A.; Laskar, T.; Servillat, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Levan, A. J.; Tunnicliffe, R. L. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Fox, D. B. [Department of Astronomy and Astrophysics, 525 Davey Laboratory, Pennsylvania State University, University Park, PA 16802 (United States); Perley, D. A. [Cahill Center for Astronomy and Astrophysics, Room 232, California Institute of Technology, Pasadena, CA 91125 (United States); Cenko, S. B. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Persson, S. E.; Monson, A. J.; Kelson, D. D.; Birk, C.; Murphy, D. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Anglada, G. [Institut fuer Astrophysik, Friedrich-Hund-Platz 1, Universitaet Goettingen, D-37077 Goettingen (Germany) 2013-05-20 We present observations of the afterglows and host galaxies of three short-duration gamma-ray bursts (GRBs): 100625A, 101219A, and 110112A. We find that GRB 100625A occurred in a z = 0.452 early-type galaxy with a stellar mass of Almost-Equal-To 4.6 Multiplication-Sign 10{sup 9} M{sub Sun} and a stellar population age of Almost-Equal-To 0.7 Gyr, and GRB 101219A originated in a star-forming galaxy at z = 0.718 with a stellar mass of Almost-Equal-To 1.4 Multiplication-Sign 10{sup 9} M{sub Sun }, a star formation rate of Almost-Equal-To 16 M{sub Sun} yr{sup -1}, and a stellar population age of Almost-Equal-To 50 Myr. We also report the discovery of the optical afterglow of GRB 110112A, which lacks a coincident host galaxy to i {approx}> 26 mag, and we cannot conclusively identify any field galaxy as a possible host. From afterglow modeling, the bursts have inferred circumburst densities of Almost-Equal-To 10{sup -4}-1 cm{sup -3} and isotropic-equivalent gamma-ray and kinetic energies of Almost-Equal-To 10{sup 50}-10{sup 51} erg. These three events highlight the diversity of galactic environments that host short GRBs. To quantify this diversity, we use the sample of 36 Swift short GRBs with robust associations to an environment ({approx}1/2 of 68 short bursts detected by Swift to 2012 May) and classify bursts originating from four types of environments: late-type ( Almost-Equal-To 50%), early-type ( Almost-Equal-To 15%), inconclusive ( Almost-Equal-To 20%), and ''host-less'' (lacking a coincident host galaxy to limits of {approx}> 26 mag; Almost-Equal-To 15%). To find likely ranges for the true late- and early-type fractions, we assign each of the host-less bursts to either the late- or early-type category using probabilistic arguments and consider the scenario that all hosts in the inconclusive category are early-type galaxies to set an upper bound on the early-type fraction. We calculate most likely ranges for the late- and early-type fractions of 11. DISSECTING THE QUASAR MAIN SEQUENCE: INSIGHT FROM HOST GALAXY PROPERTIES Sun, Jiayi [Tsinghua Center for Astrophysics, Department of Physics, Tsinghua University, Beijing 100084 (China); Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States) 2015-05-01 The diverse properties of broad-line quasars appear to follow a well-defined main sequence along which the optical Fe ii strength increases. It has been suggested that this sequence is mainly driven by the Eddington ratio (L/L{sub Edd}) of the black hole (BH) accretion. Shen and Ho demonstrated with quasar clustering analysis that the average BH mass decreases with increasing Fe ii strength when quasar luminosity is fixed, consistent with this suggestion. Here we perform an independent test by measuring the stellar velocity dispersion σ{sub *} (hence, the BH mass via the M–σ{sub *} relation) from decomposed host spectra in low-redshift Sloan Digital Sky Survey quasars. We found that at fixed quasar luminosity, σ{sub *} systematically decreases with increasing Fe ii strength, confirming that the Eddington ratio increases with Fe ii strength. We also found that at fixed luminosity and Fe ii strength, there is little dependence of σ{sub *} on the broad Hβ FWHM. These new results reinforce the framework that the Eddington ratio and orientation govern most of the diversity seen in broad-line quasar properties. 12. Dissecting the Quasar Main Sequence: Insight from Host Galaxy Properties Sun, Jiayi; Shen, Yue 2015-05-01 The diverse properties of broad-line quasars appear to follow a well-defined main sequence along which the optical Fe ii strength increases. It has been suggested that this sequence is mainly driven by the Eddington ratio (L/LEdd) of the black hole (BH) accretion. Shen & Ho demonstrated with quasar clustering analysis that the average BH mass decreases with increasing Fe ii strength when quasar luminosity is fixed, consistent with this suggestion. Here we perform an independent test by measuring the stellar velocity dispersion σ* (hence, the BH mass via the M-σ* relation) from decomposed host spectra in low-redshift Sloan Digital Sky Survey quasars. We found that at fixed quasar luminosity, σ* systematically decreases with increasing Fe ii strength, confirming that the Eddington ratio increases with Fe ii strength. We also found that at fixed luminosity and Fe ii strength, there is little dependence of σ* on the broad Hβ FWHM. These new results reinforce the framework that the Eddington ratio and orientation govern most of the diversity seen in broad-line quasar properties. 13. Dissecting the quasar main sequence: insight from host galaxy properties Sun, Jiayi 2015-01-01 The diverse properties of broad-line quasars appear to follow a well-defined main sequence along which the optical FeII strength increases. It has been suggested that this sequence is mainly driven by the Eddington ratio (L/L_Edd) of the black hole (BH) accretion. Shen & Ho demonstrated with quasar clustering analysis that the average BH mass decreases with increasing FeII strength when quasar luminosity is fixed, consistent with this suggestion. Here we perform an independent test by measuring the stellar velocity dispersion sigma* (hence the BH mass via the M-sigma* relation) from decomposed host spectra in low-redshift Sloan Digital Sky Survey quasars. We found that at fixed quasar luminosity, sigma* systematically decreases with increasing FeII strength, confirming that Eddington ratio increases with FeII strength. We also found that at fixed luminosity and FeII strength, there is little dependence of sigma* on the broad Hbeta FWHM. These new results reinforce the framework put forward by Shen & H... 14. Origins of short gamma-ray bursts deduced from offsets in their host galaxies revisited Xiao-Hong Cui; Shigehiro Nagataki; Junichi Aoi; Ren-Xin Xu 2012-01-01 The spatial distribution of short Gamma-ray bursts (GRBs) in their host galaxies provides us with an opportunity to investigate their origins.Based on the currently observed distribution of short GRBs relative to their host galaxies,we obtain the fraction of the component that traces the mergers of binary compact objects and the one that traces star formation rate (such as massive stars) in early- and late-type host galaxies.From the analysis of projected offset distribution and only based on population synthesis and massive star models,we find that the fraction of massive stars is 0.37+0.42-0.37 with an error at the lσ level for a sample with 22 short GRBs in the literature.From these results,it is hard to accept that the origin of short GRBs with observed statistics is well described by current models using only the offset distribution.The uncertainties in observational localizations of short GRBs also strongly affect the resulting fraction. 15. Kinematics and Host-Galaxy Properties Suggest a Nuclear Origin for Calcium-Rich Supernova Progenitors Foley, Ryan J 2015-01-01 Calcium-rich supernovae (Ca-rich SNe) are peculiar low-luminosity SNe Ib with relatively strong Ca spectral lines at ~2 months after peak brightness. This class also has an extended projected offset distribution, with several members of the class offset from their host galaxies by 30 - 150 kpc. There is no indication of any stellar population at the SN positions. Using a sample of 13 Ca-rich SNe, we present kinematic evidence that the progenitors of Ca-rich SNe originate near the centers of their host galaxies and are kicked to the locations of the SN explosions. Specifically, SNe with small projected offsets have large line-of-sight velocity shifts as determined by nebular lines, while those with large projected offsets have no significant velocity shifts. Therefore, the velocity shifts must not be primarily the result of the SN explosion. There is an excess of SNe with blueshifted velocity shifts within two isophotal radii (5/6 SNe), indicating that the SNe are moving away from their host galaxies and redsh... 16. Taking stock of SLSN and LGRB host galaxy comparison using a complete sample of LGRBs Japelj, J; Salvaterra, R; Hunt, L K; Mannucci, F 2016-01-01 Long gamma-ray bursts (LGRBs) and superluminous supernovae (SLSNe) are both explosive transients with very massive progenitor stars. Clues about the nature of the progenitors can be found by investigating environments in which such transients occur. While studies of LGRB host galaxies have a long history, dedicated observational campaigns have only recently resulted in a high enough number of photometrically and spectroscopically observed SLSN hosts to allow statistically significant analysis of their properties. In this paper we make a comparison of the host galaxies of hydrogen-poor (H-poor) SLSNe and the Swift/BAT6 sample of LGRBs. In contrast to previous studies we use a complete sample of LGRBs and we address a special attention to the comparison methodology and the selection of SLSN sample whose data have been compiled from the available literature. At intermediate redshifts (0.3 < z < 0.7) the two classes of transients select galaxies whose properties (stellar mass, luminosity, star-formation rat... 17. Distributions of quasar hosts on the galaxy main-sequence plane Zhang, Zhoujian; Rieke, George H; Xia, Xiaoyang; Wang, Yikang; Sun, Bingqing; Wan, Linfeng 2016-01-01 The relation between star formation rates and stellar masses, i.e. the galaxy main sequence, is a useful diagnostic of galaxy evolution. We present the distributions relative to the main sequence of 55 optically-selected PG and 12 near-IR-selected 2MASS quasars at z <= 0.5. We estimate the quasar host stellar masses from Hubble Space Telescope or ground-based AO photometry, and the star formation rates through the mid-infrared aromatic features and far-IR photometry. We find that PG quasar hosts more or less follow the main sequence defined by normal star-forming galaxies while 2MASS quasar hosts lie systematically above the main sequence. PG and 2MASS quasars with higher nuclear luminosities seem to have higher specific SFRs (sSFRs), although there is a large scatter. No trends are seen between sSFRs and SMBH masses, Eddington ratios or even morphology types (ellipticals, spirals and mergers). Our results could be placed in an evolutionary scenario with quasars emerging during the transition from ULIRGs/m... 18. The Dwarf Starburst Host Galaxy of a Type Ia SN at z = 1.55 from CANDELS Frederiksen, Teddy F; Maund, Justyn R; Rodney, Steven A; Riess, Adam G; Dahlen, Tomas; Mobasher, Bahram 2012-01-01 We present VLT/X-shooter observations of a high redshift, type Ia supernova host galaxy, discovered with HST/WFC3 as part of the CANDELS Supernova project. The galaxy exhibits strong emission lines of Ly{\\alpha}, [O II], H{\\beta}, [O III], and H{\\alpha} at z = 1.54992(+0.00008-0.00004). From the emission-line fluxes and SED fitting of broad-band photometry we rule out AGN activity and characterize the host galaxy as a young, low mass, metal poor, starburst galaxy with low intrinsic extinction and high Ly{\\alpha} escape fraction. The host galaxy stands out in terms of the star formation, stellar mass, and metallicity compared to its lower redshift counterparts, mainly because of its high specific star-formation rate. If valid for a larger sample of high-redshift SN Ia host galaxies, such changes in the host galaxy properties with redshift are of interest because of the potential impact on the use of SN Ia as standard candles in cosmology. 19. The Sloan Digital Sky Survey Reverberation Mapping Project: Post-Starburst Signatures in Quasar Host Galaxies at z > 1 Matsuoka, Yoshiki; Strauss, Michael A.; Shen, Yue; Brandt, William N.; Greene, Jenny E.; Ho, Luis C.; Schneider, Donald P.; Sun, Mouyuan; Trump, Jonathan R. 2015-10-01 Quasar host galaxies are key for understanding the relation between galaxies and the supermassive black holes (SMBHs) at their centers. We present a study of 191 broad-line quasars and their host galaxies at z\\lt 1, using high signal-to-noise ratio (S/N) spectra produced by the Sloan Digital Sky Survey Reverberation Mapping project. Clear detection of stellar absorption lines allows a reliable decomposition of the observed spectra into nuclear and host components, using spectral models of quasar and stellar radiations as well as emission lines from the interstellar medium. We estimate age, mass {M}*, and velocity dispersion {σ }* of the host stars, the star formation rate (SFR), quasar luminosity, and SMBH mass {M}\\bullet , for each object. The quasars are preferentially hosted by massive galaxies with {M}*˜ {10}11 {M}⊙ characterized by stellar ages around 1 billion yr, which coincides with the transition phase of normal galaxies from the blue cloud to the red sequence. The host galaxies have relatively low SFRs and fall below the main sequence of star-forming galaxies at similar redshifts. These facts suggest that the hosts have experienced an episode of major star formation sometime in the past 1 billion yr, which was subsequently quenched or suppressed. The derived {M}\\bullet -{σ }* and {M}\\bullet -{M}* relations agree with our past measurements and are consistent with no evolution from the local universe. The present analysis demonstrates that reliable measurements of stellar properties of quasar host galaxies are possible with high-S/N fiber spectra, which will be acquired in large numbers with future powerful instruments such as the Subaru Prime Focus Spectrograph. 20. Tidally Induced Bars in Dwarf Galaxies on Different Orbits around a Milky Way-like Host Gajda, Grzegorz; Łokas, Ewa L.; Athanassoula, E. 2017-06-01 Bars in galaxies may develop through a global instability or as a result of an interaction with another system. We study bar formation in disky dwarf galaxies orbiting a Milky Way-like galaxy. We employ N-body simulations to study the impact of the initial orbital parameters: the size of the dwarf galaxy orbit, and the inclination of its disk with respect to the orbital plane. In all cases, a bar develops in the center of the dwarf during the first pericenter on its orbit around the host. Between subsequent pericenter passages, the bars are stable, but at the pericenters, they are usually weakened and shortened. The initial properties and details of the further evolution of the bars depend heavily on the orbital configuration. We find that for the exactly prograde orientation, the strongest bar is formed for the intermediate-sized orbit. On the tighter orbit, the disk is too disturbed and stripped to form a strong bar. On the wider orbit, the tidal interaction is too weak. The dependence on the disk inclination is such that weaker bars form in more inclined disks. The bars experience either a very weak buckling or none at all. We do not observe any secular evolution, possibly because the dwarfs are perturbed at each pericenter passage. The rotation speed of the bars can be classified as slow (R CR/l bar ˜ 2-3). We attribute this to the loss of a significant fraction of the disk rotation during the encounter with the host galaxy. 1. The Connection between the Host Halo and the Satellite Galaxies of the Milky Way Lu, Yu; Benson, Andrew; Mao, Yao-Yuan; Tonnesen, Stephanie; Peter, Annika H. G.; Wetzel, Andrew R.; Boylan-Kolchin, Michael; Wechsler, Risa H. 2016-10-01 Many properties of the Milky Way’s (MW) dark matter halo, including its mass-assembly history, concentration, and subhalo population, remain poorly constrained. We explore the connection between these properties of the MW and its satellite galaxy population, especially the implication of the presence of the Magellanic Clouds for the properties of the MW halo. Using a suite of high-resolution N-body simulations of MW-mass halos with a fixed final {M}{vir}˜ {10}12.1 {M}⊙ , we find that the presence of Magellanic Cloud-like satellites strongly correlates with the assembly history, concentration, and subhalo population of the host halo, such that MW-mass systems with Magellanic Clouds have lower concentration, more rapid recent accretion, and more massive subhalos than typical halos of the same mass. Using a flexible semi-analytic galaxy formation model that is tuned to reproduce the stellar mass function of the classical dwarf galaxies of the MW with Markov-Chain Monte-Carlo, we show that adopting host halos with different mass-assembly histories and concentrations can lead to different best-fit models for galaxy-formation physics, especially for the strength of feedback. These biases arise because the presence of the Magellanic Clouds boosts the overall population of high-mass subhalos, thus requiring a different stellar-mass-to-halo-mass ratio to match the data. These biases also lead to significant differences in the mass-metallicity relation, the kinematics of low-mass satellites, the number counts of small satellites associated with the Magellanic Clouds, and the stellar mass of MW itself. Observations of these galaxy properties can thus provide useful constraints on the properties of the MW halo. 2. Towards a comprehensive picture of powerful quasars, their host galaxies and quasar winds at z ~ 0.5 Wylezalek, Dominika; Liu, Guilin; Obied, Georges 2016-01-01 Luminous type-2 quasars in which the glow from the central black hole is obscured by dust are ideal targets for studying their host galaxies and the quasars' effect on galaxy evolution. Such feedback appears ubiquitous in luminous obscured quasars where high velocity ionized nebulae have been found. We present rest-frame yellow-band (~5000 Angstroms) observations using the Hubble Space Telescope for a sample of 20 luminous quasar host galaxies at 0.2 < z < 0.6 selected from the Sloan Digital Sky Survey. For the first time, we combine host galaxy observations with geometric measurements of quasar illumination using blue-band HST observations and [OIII] integral field unit observations probing the quasar winds. The HST images reveal bright merger signatures in about half the galaxies; a significantly higher fraction than in comparison inactive ellipticals. We show that the host galaxies are primarily bulge-dominated, with masses close to M*, but belong to < 30% of elliptical galaxies that are highly st... 3. SALT spectroscopic observations of galaxy clusters detected by ACT and a Type II quasar hosted by a brightest cluster galaxy Kirk, Brian; Cress, Catherine; Crawford, Steven M; Hughes, John P; Battaglia, Nicholas; Bond, J Richard; Burke, Claire; Gralla, Megan B; Hajian, Amir; Hasselfield, Matthew; Hincks, Adam D; Infante, Leopoldo; Kosowsky, Arthur; Marriage, Tobias A; Menanteau, Felipe; Moodley, Kavilan; Niemack, Michael D; Sievers, Jonathan L; Sifón, Cristóbal; Wilson, Susan; Wollack, Edward J; Zunckel, Caroline 2014-01-01 We present Southern African Large Telescope (SALT) follow-up observations of seven massive clusters detected by the Atacama Cosmology Telescope (ACT) on the celestial equator using the Sunyaev-Zel'dovich (SZ) effect. We conducted multi-object spectroscopic observations with the Robert Stobie Spectrograph in order to measure galaxy redshifts in each cluster field, determine the cluster line-of-sight velocity dispersions, and infer the cluster dynamical masses. We find that the clusters, which span the redshift range 0.3 < z < 0.55, range in mass from (5 -- 20) x 10$^{14}$solar masses (M200c). Their masses, given their SZ signals, are similar to those of southern hemisphere ACT clusters previously observed using Gemini and the VLT. We note that the brightest cluster galaxy in one of the systems studied, ACT-CL J0320.4+0032 at z = 0.38, hosts a Type II quasar. To our knowledge, this is only the third such system discovered, and therefore may be a rare example of a very massive halo in which quasar-mode fe... 4. The Molecular Gas Content of z<0.1 Radio Galaxies: Linking the AGN Accretion Mode to Host Galaxy Properties Smolcic, V 2011-01-01 One of the main achievements in modern cosmology is the so-called unified model', which successfully describes most classes of active galactic nuclei (AGN) within a single physical scheme. However, there is a particular class of radio-luminous AGN that presently cannot be explained within this framework -- the low-excitation' radio AGN (LERAGN). Recently, a scenario has been put forward which predicts that LERAGN, and their regular high-excitation' radio AGN (HERAGN) counterparts represent different (red sequence vs. green valley) phases of galaxy evolution. These different evolutionary states are also expected to be reflected in their host galaxy properties, in particular their cold gas content. To test this, here we present CO(1-0) observations toward a sample of 11 of these systems conducted with CARMA. Combining our observations with literature data, we derive molecular gas masses (or upper limits) for a complete, representative, sample of 21 z<0.1 radio AGN. Our results yield that HERAGN on average... 5. Exploring Damped Lyα System Host Galaxies Using Gamma-Ray Bursts Toy, Vicki L.; Cucchiara, Antonino; Veilleux, Sylvain; Fumagalli, Michele; Rafelski, Marc; Rahmati, Alireza; Cenko, S. Bradley; Capone, John I.; Pasham, Dheeraj R. 2016-12-01 We present a sample of 45 Damped Lyα system (DLA; {N}{{H}{{I}}} ≥slant 2× {10}20 {{cm}}-2) counterparts (33 detections, 12 upper limits) which host gamma-ray bursts (GRB-DLAs) in order to investigate star formation and metallicity within galaxies hosting DLAs. Our sample spans z˜ 2{--}6 and is nearly three times larger than any previously detected DLA counterparts survey based on quasar line-of-sight searches (QSO-DLAs). We report star formation rates (SFRs) from rest-frame UV photometry and spectral energy distribution modeling. We find that DLA counterpart SFRs are not correlated with either redshift or H i column density. Thanks to the combination of Hubble Space Telescope and ground-based observations, we also investigate DLA host star formation efficiency. Our GRB-DLA counterpart sample spans both higher efficiency and low efficiency star formation regions compared to the local Kennicutt-Schmidt relation, local star formation laws, and z˜ 3 cosmological simulations. We also compare the depletion times of our DLA hosts sample to other objects in the local universe; our sample appears to deviate from the star formation efficiencies measured in local spiral and dwarf galaxies. Furthermore, we find similar efficiencies as local inner disks, SMC, and Lyman-break galaxy outskirts. Finally, our enrichment time measurements show a spread of systems with under- and over-abundance of metals, which may suggest that these systems had episodic star formation and a metal enrichment/depletion as a result of strong stellar feedback and/or metal inflow/outflow. 6. The Spiral Host Galaxy of the Double Radio Source 0313-192 Keel, W C; Owen, F N; Ledlow, M J; Keel, William C.; III, Raymond E. White; Owen, Frazer N.; Ledlow, Michael J. 2006-01-01 We present new Hubble, Gemini-S, and Chandra observations of the radio galaxy 0313-192, which hosts a 350-kpc double source and jets, even though previous data have suggested that it is a spiral galaxy. We measure the bulge scale and luminosity, radial and vertical profiles of disk starlight, and consider the distributions of H II regions and absorbing dust. In each case, the HST data confirm its classification as an edge-on spiral galaxy, the only such system known to produce such an extended radio source of this kind. The Gemini near-IR images and Chandra spectral fit reveal a strongly obscured central AGN, seen through the entire ISM path length of the disk and showing X-ray evidence of additional absorption from warm or dense material close to the central object. We consider several possible mechanisms for producing such a rare combination of AGN and host properties, some combination of which may be at work. These include an unusually luminous bulge (suggesting a black hole of mass 0.5-0.9 billion solar m... 7. ON THE DEPENDENCE OF TYPE Ia SNe LUMINOSITIES ON THE METALLICITY OF THEIR HOST GALAXIES Moreno-Raya, Manuel E.; Mollá, Mercedes [Dpto.de Investigación Básica, C.I.E.M.A.T., Avda. Complutense 40, E-28040 Madrid (Spain); López-Sánchez, Ángel R. [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Galbany, Lluís [Millennium Institute of Astrophysics MAS, Nuncio Monseñor Sótero Sanz 100, Providencia, 7500011 Santiago (Chile); Vílchez, José Manuel [Instituto de Astrofísica de Andalucía (CSIC), Apdo. 3004, E-18080 Granada (Spain); Rosell, Aurelio Carnero [Observatório Nacional, and LIneA Laboratório Interinstitucional de e-Astronomia, Rua Gal. José Cristino 77 Rio de Janeiro, RJ 20921-400 (Brazil); Domínguez, Inmaculada, E-mail: [email protected] [Departamento de Física Teórica y del Cosmos, Universidad de Granada, E-18071 Granada (Spain) 2016-02-10 The metallicity of the progenitor system producing a type Ia supernova (SN Ia) could play a role in its maximum luminosity, as suggested by theoretical predictions. We present an observational study to investigate if such a relationship exists. Using the 4.2 m William Herschel Telescope (WHT) we have obtained intermediate-resolution spectroscopy data of a sample of 28 local galaxies hosting SNe Ia, for which distances have been derived using methods independent of those based on SN Ia parameters. From the emission lines observed in their optical spectra, we derived the gas-phase oxygen abundance in the region where each SN Ia exploded. Our data show a trend, with an 80% of chance not being due to random fluctuation, between SNe Ia absolute magnitudes and the oxygen abundances of the host galaxies, in the sense that luminosities tend to be higher for galaxies with lower metallicities. This result seems likely to be in agreement with both the theoretically expected behavior and with other observational results. This dependence M{sub B}–Z might induce systematic errors when it is not considered when deriving SNe Ia luminosities and then using them to derive cosmological distances. 8. The connection between the host halo and the satellite galaxies of the Milky Way Lu, Yu; Mao, Yao-Yuan; Tonnesen, Stephanie; Peter, Annika H G; Wetzel, Andrew R; Boylan-Kolchin, Michael; Wechsler, Risa H 2016-01-01 Many properties of the Milky Way's dark matter halo, including its mass assembly history, concentration, and subhalo population, remain poorly constrained. We explore the connection between these properties of the Milky Way and its satellite galaxy population, especially the implication of the presence of the Magellanic Clouds for the properties of the Milky Way halo. Using a suite of high-resolution N-body simulations of Milky Way-mass halos, we find that the presence of Magellanic Cloud-like satellites strongly correlates with the assembly history, concentration, and subhalo population of the host halo, such that Milky Way-mass systems with Magellanic Clouds have lower concentration, more rapid recent accretion, and more massive subhalos than typical halos of the same mass. Using a flexible semi-analytic galaxy formation model that is tuned to reproduce the stellar mass function of the classical dwarf galaxies of the Milky Way with Markov-Chain Monte-Carlo, we show that adopting host halos with different ma... 9. Properties of a Gamma Ray Burst Host Galaxy at z ~ 5 Price, P A; Cowie, L L; Burnell, J Bell; Berger, E; Cucchiara, A; Fox, D B; Hook, I; Kulkarni, S R; Penprase, B; Roth, K C; Schmidt, B 2007-01-01 We describe the properties of the host galaxy of the gamma-ray burst GRB060510B based on a spectrum of the burst afterglow obtained with the Gemini North 8m telescope. The galaxy lies at a redshift of z = 4.941 making it the fourth highest spectroscopically identified burst host. However, it is the second highest redshift galaxy for which the quality of the spectrum permits a detailed metallicity analysis. The neutral hydrogen column density has a logarithmic value of 21.0--21.2 cm^-2 and the weak metal lines of Ni, S and Fe show that the metallicity is in excess of a tenth of solar which is far above the metallicities in damped Lyman alpha absorbers at high redshift. The tightest constraint is from the Fe lines which place [Fe/H] in excess of -0.8. We argue that the results suggest that metallicity bias could be a serious problem with inferring star formation from the GRB population and consider how future higher quality measurements could be used to resolve this question. 10. On the dependence of the type Ia SNe luminosities on the metallicity of their host galaxies Moreno-Raya, Manuel E; López-Sánchez, Ángel R; Galbany, Lluís; Vílchez, José; Carnero, Aurelio; Domínguez, Inma 2015-01-01 The metallicity of the progenitor system producing a type Ia supernova (SN Ia) could play a role in its maximum luminosity, as suggested by theoretical predictions. We present an observational study to investigate if such a relationship there exists. Using the 4.2m WHT we have obtained intermediate-resolution spectroscopy data of a sample of 28 local galaxies hosting SNe Ia, for which distances have been derived using methods independent to those based on the own SN Ia parameters. From the emission lines observed in their optical spectrum, we derived the gas-phase oxygen abundance in the region where each SN Ia exploded. Our data show a trend, with a 80% of chance not to be due to random fluctuation, between SNe Ia absolute magnitudes and the oxygen abundances of the host galaxies, in the sense that luminosities tend to be higher for galaxies with lower metallicities. This result seems like to be in agreement with both the theoretically expected behavior, and with other observational results. This dependence ... 11. The Role of Radiation Pressure in the Narrow Line Regions of Seyfert Host Galaxies Davies, Rebecca L; Kewley, Lisa J; Groves, Brent; Sutherland, Ralph; Hampton, Elise J; Shastri, Prajval; Kharb, Preeti; Bhatt, Harish; Scharwächter, Julia; Jin, Chichuan; Banfield, Julie; Zaw, Ingyin; James, Bethan; Juneau, Stéphanie; Srivastava, Shweta 2016-01-01 We investigate the relative significance of radiation pressure and gas pressure in the extended narrow line regions (ENLRs) of four Seyfert galaxies from the integral field Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). We demonstrate that there exist two distinct types of starburst-AGN mixing curves on standard emission line diagnostic diagrams which reflect the balance between gas pressure and radiation pressure in the ENLR. In two of the galaxies the ENLR is radiation pressure dominated throughout and the ionization parameter remains constant (log U ~ 0). In the other two galaxies radiation pressure is initially important, but gas pressure becomes dominant as the ionization parameter in the ENLR decreases from log U ~ 0 to -3.4 <= log U <= -3.2. Where radiation pressure is dominant, the AGN regulates the density of the interstellar medium on kpc scales and may therefore have a direct impact on star formation activity and/or the incidence of outflows in the host galaxy to scales fa... 12. The Role of Radiation Pressure in the Narrow Line Regions of Seyfert Host Galaxies Davies, Rebecca L.; Dopita, Michael A.; Kewley, Lisa; Groves, Brent; Sutherland, Ralph; Hampton, Elise J.; Shastri, Prajval; Kharb, Preeti; Bhatt, Harish; Scharwächter, Julia; Jin, Chichuan; Banfield, Julie; Zaw, Ingyin; James, Bethan; Juneau, Stéphanie; Srivastava, Shweta 2016-06-01 We investigate the relative significance of radiation pressure and gas pressure in the extended narrow line regions (ENLRs) of four Seyfert galaxies from the integral field Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). We demonstrate that there exist two distinct types of starburst-active galactic nucleus (AGN) mixing curves on standard emission line diagnostic diagrams, which reflect the balance between gas pressure and radiation pressure in the ENLR. In two of the galaxies the ENLR is radiation pressure dominated throughout and the ionization parameter remains constant (log U ˜ 0). In the other two galaxies radiation pressure is initially important, but gas pressure becomes dominant as the ionization parameter in the ENLR decreases from log U ˜ 0 to -3.2 ≲ log U ≲ -3.4. Where radiation pressure is dominant, the AGN regulates the density of the interstellar medium on kiloparsec scales and may therefore have a direct impact on star formation activity and/or the incidence of outflows in the host galaxy to scales far beyond the zone of influence of the black hole. We find that both radiation pressure dominated and gas pressure dominated ENLRs are dynamically active with evidence for outflows, indicating that radiation pressure may be an important source of AGN feedback even when it is not dominant over the entire ENLR. 13. Supermassive Black Holes and Their Host Galaxies - I. Bulge luminosities from dedicated near-infrared data Läsker, Ronald; van de Ven, Glenn 2013-01-01 In an effort to secure, refine and supplement the relation between central Supermassive Black Hole masses (Mbh), and the bulge luminosities of their host galaxies, (Lbul), we obtained deep, high spatial resolution K-band images of 35 nearby galaxies with securely measured Mbh, using the wide-field WIRCam imager at the Canada-France-Hawaii-Telescope (CFHT). A dedicated data reduction and sky subtraction strategy was adopted to estimate the brightness and structure of the sky, a critical step when tracing the light distribution of extended objects in the near-infrared. From the final image product, bulge and total magnitudes were extracted via two-dimensional profile fitting. As a first order approximation, all galaxies were modeled using a simple Sersic-bulge + exponential-disk decomposition. However, we found that such models did not adequately describe the structure that we observe in a large fraction of our sample galaxies which often include cores, bars, nuclei, inner disks, spiral arms, rings and envelope... 14. Origin of the Correlations Between Supermassive Black Holes and Their Host Galaxies Sherman, Sydney; Zhu, Qirong; Trump, Jonathan R; Li, Yuexing 2014-01-01 Observations have shown that supermassive black holes in nearby elliptical galaxies correlate tightly with the stellar velocity dispersion (the$\\MBH - \\sigma$relation) and the stellar mass (the$\\MBH - \\Mhost$relation) of their host spheroids. However, the origin of these correlations remains ambiguous. In a previous paper by Zhu et al., we proposed a model which links the M-$\\sigma$relation to the the dynamical state of the system and the$\\MBH - \\Mhost$relation to the self-regulation of galaxy growth. To test this model, we compile a sample of observed galaxies with different properties and examine the dependence of the above correlations on these parameters. We find that galaxies that satisfy the the$\\MBH - \\sigma$correlation appear to have reached virial equilibrium, as indicated by the ratio between kinetic energy and gravitational potential, 2K/U$\\sim$1. Furthermore, the ratio of black hole accretion rate to star formation rate remains nearly constant, BHAR /SFR$\\sim10^{-3}, in active gala... 15. Uncovering hidden black holes: Obscured AGN and their relationship to the host galaxy LaMassa, Stephanie M. that accurately trace AGN flux, we have shown that these processes are significantly correlated. This link suggests that supermassive black holes and their host galaxies grow simultaneously in the local universe. 16. HUBBLE SPACE TELESCOPE Observations of the Host Galaxy of GRB 970508 Fruchter, A. S.; Pian, E.; Gibbons, R.; Thorsett, S. E.; Ferguson, H.; Petro, L.; Sahu, K. C.; Livio, M.; Caraveo, P.; Frontera, F.; Kouveliotou, C.; Macchetto, D.; Palazzi, E.; Pedersen, H.; Tavani, M.; van Paradijs, J. 2000-12-01 We report on observations of the field of GRB 970508 made in 1998 early August, 454 days after outburst, with the STIS CCD camera on board the Hubble Space Telescope (HST). The images, taken in open filter (50CCD) mode, clearly reveal the presence of a galaxy that was overwhelmed in earlier (1997 June) HST images by emission from the optical transient (OT). The galaxy is regular in shape: after correcting for the HST/STIS PSF, it is well fitted by an exponential disk with a scale length of 0.046"+/-0.006" and an ellipticity of 0.70+/-0.07. All observations are marginally consistent with a continuous decline in OT emission as t-1.3 beginning 2 days after outburst; however, we find no direct evidence in the late-time HST image for emission from the OT, and the surface brightness profile of the galaxy is most regular if we assume that the OT emission is negligible, suggesting that the OT may have faded more rapidly at late times than is predicted by the power-law decay. Due to the wide bandwidth of the STIS clear mode, the estimated magnitude of the galaxy is dependent on the galaxy spectrum that is assumed. Using colors obtained from late-time ground-based observations to constrain the spectrum, we find V=25.4+/-0.15, a few tenths of a magnitude brighter than earlier ground-based estimates that were obtained by observing the total light of the galaxy and the OT and then subtracting the estimated OT brightness, assuming that it fades as a single power law. This again suggests that the OT may have faded faster at late time than the power law predicts. The position of the OT agrees with that of the isophotal center of the galaxy to 0.01", which, at the galaxy redshift z=0.83, corresponds to an offset from the center of the host of <~70 pc. This remarkable agreement raises the possibility that the gamma-ray burst may have been associated with either an active galactic nucleus or a nuclear starburst. 17. The luminosity and stellar mass functions of GRB host galaxies: Insight into the metallicity bias Trenti, Michele; Jimenez, Raul 2014-01-01 [Abridged] Long-Duration Gamma-Ray Bursts (GRBs) are powerful probes of the star formation history of the Universe, but the correlation between the two depends on the highly debated presence and strength of a metallicity bias. To investigate this correlation, we use a phenomenological model that successfully describes star formation rates, luminosities and stellar masses of star forming galaxies, and apply it to GRB production. We predict the comoving GRB rate and luminosities/stellar masses of host galaxies depending on the presence (or absence) of a metallicity bias, highlighting that apparent conflicts among previous studies might disappear following a comprehensive data-model comparison. We conclude that: (1) Our best fitting model includes a moderate metallicity bias, broadly consistent with the large majority of the long-duration GRBs in metal-poor environments originating from a collapsar (~83%), but with a secondary contribution from a metal-independent production channel, such as binary evolution; (2... 18. A tale of two feedbacks: Star formation in the host galaxies of radio AGNs Karouzos, Marios; Im, Myungshin; Jeon, Yiseul; Kim, Ji Hoon [CEOU-Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul (Korea, Republic of); Trichas, Markos [Airbus Defence and Space, Gunnels Wood Road, Stevenage SG1 2AS (United Kingdom); Goto, Tomo [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Malkan, Matt [Division of Astronomy and Astrophysics, 3-714 UCLA, CA 90095-1547 (United States); Ruiz, Angel [Inter-University Centre for Astronomy and Astrophysics (IUCAA), Post Bag 4, Ganeshkhind, 411 007 Pune (India); Lee, Hyung Mok; Kim, Seong Jin [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul (Korea, Republic of); Oi, Nagisa; Matsuhara, Hideo; Takagi, Toshinobu; Murata, K.; Wada, Takehiko; Wada, Kensuke [Institute of Space and Astronautical Science, JAXA, Yoshino-dai 3-1-1, Sagamihara, Kanagawa 229-8510 (Japan); Shim, Hyunjin [Department of Earth Science Education, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hanami, Hitoshi [Physics Section, Faculty of Humanities, Iwate University, Ueda 3 chome, 18-34 Morioka, Morioka, Iwate 020-8550 (Japan); Serjeant, Stephen; White, Glenn J., E-mail: [email protected] [Department of Physics and Astronomy, The Open University, Walton Hall, Milton Keynes (United Kingdom); and others 2014-04-01 Several lines of argument support the existence of a link between activity at the nuclei of galaxies, in the form of an accreting supermassive black hole, and star formation activity in these galaxies. Radio jets have long been argued to be an ideal mechanism that allows active galactic nuclei (AGNs) to interact with their host galaxies and affect star formation. We use a sample of radio sources in the North Ecliptic Pole (NEP) field to study the nature of this putative link, by means of spectral energy distribution (SED) fitting. We employ the excellent spectral coverage of the AKARI infrared space telescope and the rich ancillary data available in the NEP to build SEDs extending from UV to far-IR wavelengths. We find a significant AGN component in our sample of relatively faint radio sources (host galaxy, independent of the radio luminosity. In contrast, for narrow redshift and AGN luminosity ranges, we find that increasing radio luminosity leads to a decrease in the specific star formation rate. The most radio-loud AGNs are found to lie on the main sequence of star formation for their respective redshifts. For the first time, we potentially see such a two-sided feedback process in the same sample. We discuss the possible suppression of star formation, but not total quenching, in systems with strong radio jets, that supports the maintenance nature of feedback from radio AGN jets. 19. Molecular content of a type-Ia SN host galaxy at z=0.6 Melchior, A -L 2007-01-01 We study the properties and the molecular content of the host of a type-Ia supernova (SN1997ey). This z=0.575 host is the brightest submillimetre source of the sample of type-Ia supernova hosts observed at 450um and 850um by Farrah et al.. Observations were performed at IRAM-30m to search for CO(2-1) and CO(3-2) lines in good weather conditions but no signal was detected. The star formation rate cannot exceed 50 M_sol/yr. These negative results are confronted with an optical analysis of a Keck spectrum and other data archives. We reach the conclusion that this galaxy is a late-type system (0.7 L^B_*), with a small residual star-formation activity (0.2 M_sol/yr) detected in the optical. No source of heating (AGN or starburst) is found to explain the submillimetre-continuum flux and the non-CO detection excludes the presence of a large amount of cold gas. We thus suggest that either the star formation activity is hidden in the nucleus (with A_V ~ 4) or this galaxy is passive or anemic and this flux might be ass... 20. THE CLUSTERING OF ALFALFA GALAXIES: DEPENDENCE ON H I MASS, RELATIONSHIP WITH OPTICAL SAMPLES, AND CLUES OF HOST HALO PROPERTIES Papastergis, Emmanouil; Giovanelli, Riccardo; Haynes, Martha P.; Jones, Michael G. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Rodríguez-Puebla, Aldo, E-mail: [email protected], E-mail: [email protected], E-mail: [email protected], E-mail: [email protected], E-mail: [email protected] [Instituto de Astronomía, Universidad Nacional Autónoma de México, A. P. 70-264, 04510 México, D.F. (Mexico) 2013-10-10 We use a sample of ≈6000 galaxies detected by the Arecibo Legacy Fast ALFA (ALFALFA) 21 cm survey to measure the clustering properties of H I-selected galaxies. We find no convincing evidence for a dependence of clustering on galactic atomic hydrogen (H I) mass, over the range M{sub H{sub I}} ≈ 10{sup 8.5}-10{sup 10.5} M{sub ☉}. We show that previously reported results of weaker clustering for low H I mass galaxies are probably due to finite-volume effects. In addition, we compare the clustering of ALFALFA galaxies with optically selected samples drawn from the Sloan Digital Sky Survey (SDSS). We find that H I-selected galaxies cluster more weakly than even relatively optically faint galaxies, when no color selection is applied. Conversely, when SDSS galaxies are split based on their color, we find that the correlation function of blue optical galaxies is practically indistinguishable from that of H I-selected galaxies. At the same time, SDSS galaxies with red colors are found to cluster significantly more than H I-selected galaxies, a fact that is evident in both the projected as well as the full two-dimensional correlation function. A cross-correlation analysis further reveals that gas-rich galaxies 'avoid' being located within ≈3 Mpc of optical galaxies with red colors. Next, we consider the clustering properties of halo samples selected from the Bolshoi ΛCDM simulation. A comparison with the clustering of ALFALFA galaxies suggests that galactic H I mass is not tightly related to host halo mass and that a sizable fraction of subhalos do not host H I galaxies. Lastly, we find that we can recover fairly well the correlation function of H I galaxies by just excluding halos with low spin parameter. This finding lends support to the hypothesis that halo spin plays a key role in determining the gas content of galaxies. 1. The Fanaroff-Riley Transition and the Optical Luminosity of the Host Elliptical Galaxy Gopal-Krishna; Wiita, Paul J. 2001-01-01 We show that a model for radio source dynamics we had earlier proposed can readily reproduce the relationship between the radio power division separating the two Fanaroff-Riley classes of extragalactic radio sources and the optical luminosity of the host galaxy, as found by Owen and Ledlow (1994). In our scenario, when less powerful jets eventually slow down to the point that the advance of the working surface (i.e., hotspot) becomes subsonic with respect to the external gas, the jet's collim... 2. Exploring Gamma-Ray Bursts, Their Immediate Environment and Host Galaxies Friis, Mette 2015-01-01 Lasting anywhere from a few milliseconds to several minutes, GRBs shine hundreds of times brighter than a typical supernova, making them briefly the brightest source of cosmic gamma-ray photons in the observable Universe. This thesis focuses on 3 different aspects of GRBs: (1) The radiative mechanism of GRBs and their afterglows, i.e. the occurrence of thermal emission and the physical parameters we can determine through this emission. (2) Their host galaxies, using results from observations of GRB 121024A as a case study. (3) How they can be used to answer some of the larger astrophysical questions, more specifically in this case, to study interstellar dust and grey extinction. 3. A Compact Group of Galaxies at z = 2.48 Hosting an AGN-driven Outflow Shih, Hsin-Yi; Stockton, Alan 2015-12-01 We present observations of a remarkable compact group of galaxies at z = 2.48. Four galaxies, all within 40 kpc of each other, surround a powerful high-redshift radio source. This group comprises two compact red passive galaxies and a pair of merging galaxies. One of the red galaxies, with an apparent stellar mass of 3.6 × 1011M⊙ and an effective radius of 470 pc, is one of the most extreme examples of a massive quiescent compact galaxy found so far. One of the pair of merging galaxies hosts the active galactic nucleus (AGN) producing the large powerful radio structure. The merger is massive and enriched, consistent with the mass-metallicity relation expected at this redshift. Close to the merging nuclei, the emission lines exhibit broad and asymmetric profiles that suggest outflows powered either by a very young expanding radio jet or by AGN radiation. At ≳50 kpc from the system, we found a fainter extended-emission region that may be a part of a radio-jet-driven outflow. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The work is also based, in part, on data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan, and on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). 4. N/O abundance ratios in gamma-ray burst and supernova host galaxies at z regions Contini, M. 2017-08-01 The distribution of the N/O element abundance ratios calculated by the detailed modelling of different galaxy spectra at z emission-line region (LINER)]. N/O ratios in LGRB hosts decrease rapidly between z > 1 and z ˜ 0.1 following the N/H trend and reach the characteristic N/O ratios calculated for the H ii regions in local and nearby galaxies. The few short-period gamma-ray-burst (SGRB) hosts included in the galaxy sample show N/H ≤ 0.04 solar and O/H solar. They seem to continue the low bound N/H trend of SN hosts at z models. The results show that several LGRB hosts can be explained by star multibursting models when 12+log(O/H) models. N/O in SN hosts at log(O/H)+12 models calculated for starburst galaxies. At 12+log(O/H) > 8.5 many different objects are nested close to O/H solar with N/O ranging between the maximum corresponding to starburst galaxies and AGN and the minimum corresponding to H ii regions and SGRB. 5. A Relationship between Supermassive Black Hole Mass and the Total Gravitational Mass of the Host Galaxy Bandara, Kaushala; Simard, Luc 2009-01-01 We investigate the correlation between the mass of a central supermassive black hole and the total gravitational mass of the host galaxy (M_tot). The results are based on 43 galaxy-scale strong gravitational lenses from the Sloan Lens ACS (SLACS) Survey whose black hole masses were estimated through two scaling relations: the relation between black hole mass and Sersic index (M_bh - n) and the relation between black hole mass and stellar velocity dispersion (M_bh - sigma). We use the enclosed mass within R_200, the radius within which the density profile of the early type galaxy exceeds the critical density of the Universe by a factor of 200, determined by gravitational lens models fitted to HST imaging data, as a tracer of the total gravitational mass. The best fit correlation, where M_bh is determined from M_bh - sigma relation, is log(M_bh) = (8.18 +/- 0.11) + (1.55 +/- 0.31) (log(M_tot) - 13.0) over 2 orders of magnitude in M_bh. From a variety of tests, we find that we cannot reliably infer a connection ... 6. The host galaxies of ultra hard X-ray selected AGN Koss, Michael J. One of the great mysteries surrounding active galactic nuclei (AGN) is their triggering mechanism. Since the discovery that almost all massive galaxies host nuclear supermassive black holes, it has become clear that a trigger mechanism is required to 'turn on' and continue to fuel the central black hole. While it is established that accretion processes are responsible for the energy emitted, the source of the accreting material is still controversial. Furthermore, the energy input from phases of black hole growth is thought to be a key regulator in the formation of galaxies and the establishment of various scaling relations. Theorists often invoke galaxy mergers as the violent mechanism to drive gas into the central regions and ignite luminous quasars, but among more common moderate luminosity AGN, there has been great controversy whether secular processes or mergers dominate AGN fueling. A survey in the ultra hard X-ray band (14--195 keV) is an important new way to answer the fundamental question of AGN fueling. This method is independent of selection effects such as dust extinction and obscuration that plague surveys at other wavelengths because of the ability of the primary continuum to easily pass through large columns of obscuring gas and dust (2 keV) imaging. 7. Witnessing the transformation of a quasar host galaxy at z=1.6 Humphrey, A; Gomes, J M; Papaderos, P; Villar-Martín, M; Filho, M E; Emonts, B H C; Aretxaga, I; Binette, L; Flaquer, B Ocaña; Lagos, P; Torrealba, J 2015-01-01 A significant minority of high redshift radio galaxy (HzRG) candidates show extremely red broad band colours and remain undetected in emission lines after optical discovery' spectroscopy. In this paper we present deep GTC optical imaging and spectroscopy of one such radio galaxy, 5C 7.245, with the aim of better understanding the nature of these enigmatic objects. Our g-band image shows no significant emission coincident with the stellar emission of the host galaxy, but does reveal faint emission offset by ~3" (26 kpc) therefrom along a similar position angle to that of the radio jets, reminiscent of the alignment effect' often seen in the optically luminous HzRGs. This offset g-band source is also detected in several UV emission lines, giving it a redshift of 1.609, with emission line flux ratios inconsistent with photoionization by young stars or an AGN, but consistent with ionization by fast shocks. Based on its unusual gas geometry, we argue that in 5C 7.245 we are witnessing a rare (or rarely observed)... 8. Host Galaxy Properties and Black Hole Mass of Swift J164449.3+573451 from Multi-Wavelength Long-Term Monitoring and HST Data Yoon, Yongmin; Jeon, Yiseul; Lee, Seong-Kook; Choi, Philip; Gehrels, Neil; Pak, Soojong; Sakamoto, Takanori; Urata, Yuji 2015-01-01 We study the host galaxy properties of the tidal disruption object, Swift J164449.3+573451 using long-term optical to near-infrared (NIR) data. First, we decompose the galaxy surface brightness distribution and analyze the morphology of the host galaxy using high resolution \\emph{HST} WFC3 images. We conclude that the host galaxy is a bulge-dominant galaxy that is well described by a single S\\'{e}rsic model with S\\'{e}rsic indexn=3.43\\pm0.05$. Adding a disk component, the bulge to total host galaxy flux ratio (B/T) is$0.83\\pm0.03$, which still indicates a bulge-dominant galaxy. Second, we estimate multi-band fluxes of the host galaxy through long-term light curves. Our long-term NIR light curves reveal the pure host galaxy fluxes$\\sim500$days after the burst. We fit spectral energy distribution (SED) models to the multi-band fluxes from the optical to NIR of the host galaxy and determine its properties. The stellar mass, the star formation rate, and the age of stellar population are$\\log(M_{\\star}/M_{\\o...
9. Multi-Wavelength Studies on H2O Maser Host Galaxies
J. S. Zhang; J. Wang
2011-03-01
H2O maser emissions have been found in external galaxies for more than 30 years. Main sciences associated with extragalactic H2O masers can be summarized roughly into three parts: maser emission itself, AGN sciences and cosmology exploration. Our work in this field focusses on two projects: X-ray data analysis of individual maser source using X-ray penetrability to explore maser host obscured AGN; multi-wavelength statistical properties of the whole published H2O maser sample. Here their nuclear radio properties were investigated in detail, based on their 6-cm and 20-cm radio observation data. Comparing the radio properties between maser-detected sources and non-detected sources at similar distance scale, we find that: (1) maser host galaxies tend to have higher nuclear radio luminosity; (2) the spectral index of both samples is comparable (∼ 0.6), within the error ranges. In addition, for AGN-maser sources, the isotropic maser luminosity tends to increase with rising radio luminosity. Thus we propose the nuclear radio luminosity as one good indicator for searching AGN-masers in the future.
10. Extracting Host Galaxy Dispersion Measure and Constraining Cosmological Parameters using Fast Radio Burst Data
Yang, Yuan-Pei; Zhang, Bing
2016-10-01
The excessive dispersion measures (DMs) and high Galactic latitudes of fast radio bursts (FRBs) hint toward a cosmological origin of these mysterious transients. Methods of using measured DM and redshift z to study cosmology have been proposed, but one needs to assume a certain amount of DM contribution from the host galaxy ({{DM}}{HG}) in order to apply those methods. We introduce a slope parameter β (z)\\equiv d{ln} /d{ln}z (where {{DM}}{{E}} is the observed DM subtracting the Galactic contribution), which can be directly measured when a sample of FRBs have z measured. We show that can be roughly inferred from β and the mean values, \\overline{ } and \\bar{z}, of the sample. Through Monte Carlo simulations, we show that the mean value of local host galaxy DM, , along with other cosmological parameters (mass density {{{Ω }}}m in the ΛCDM model, and the IGM portion of the baryon energy density {{{Ω }}}b{f}{IGM}), can be independently measured through Markov Chain Monte Carlo fitting to the data.
11. Massive stars formed in atomic hydrogen reservoirs: HI observations of gamma-ray burst host galaxies
Michałowski, Michał J; Hjorth, J; Krumholz, M R; Tanvir, N R; Kamphuis, P; Burlon, D; Baes, M; Basa, S; Berta, S; Ceron, J M Castro; Crosby, D; D'Elia, V; Elliott, J; Greiner, J; Hunt, L K; Klose, S; Koprowski, M P; Floc'h, E Le; Malesani, D; Murphy, T; Guelbenzu, A Nicuesa; Palazzi, E; Rasmussen, J; Rossi, A; Savaglio, S; Schady, P; Sollerman, J; Postigo, A de Ugarte; Watson, D; van der Werf, P; Vergani, S D; Xu, D
2015-01-01
Long gamma-ray bursts (GRBs), among the most energetic events in the Universe, are explosions of massive and short-lived stars, so they pinpoint locations of recent star formation. However, several GRB host galaxies have recently been found to be deficient in molecular gas (H2), believed to be the fuel of star formation. Moreover, optical spectroscopy of GRB afterglows implies that the molecular phase constitutes only a small fraction of the gas along the GRB line-of-sight. Here we report the first ever 21 cm line observations of GRB host galaxies, using the Australia Telescope Compact Array, implying high levels of atomic hydrogen (HI), which suggests that the connection between atomic gas and star formation is stronger than previously thought, with star formation being potentially directly fuelled by atomic gas (or with very efficient HI-to-H2 conversion and rapid exhaustion of molecular gas), as has been theoretically shown to be possible. This can happen in low metallicity gas near the onset of star forma...
12. Extracting host galaxy dispersion measure and constraining cosmological parameters using fast radio burst data
Yang, Yuan-Pei
2016-01-01
The excessive dispersion measures (DMs) and high Galactic latitudes of fast radio bursts (FRBs) hint toward a cosmological origin of these mysterious transients. Methods of using measured DM and redshift $z$ to study cosmology have been proposed, but one needs to assume a certain amount of DM contribution from the host galaxy (DM$_{\\rm HG}$) in order to apply those methods. We introduce a slope parameter $\\beta(z) \\equiv d \\ln \\left / d \\ln z$ (where DM$_{\\rm E}$ is the observed DM subtracting the Galactic contribution), which can be directly measured when a sample of FRBs have $z$ measured. We show that $\\left$ can be roughly inferred from $\\beta$ and the mean values, $\\overline{\\rm \\left}$ and $\\bar z$, of the sample. Through Monte Carlo simulations, we show that the mean value of local host galaxy DM, $\\left$, along with other cosmological parameters (mass density $\\Omega_m$ in the $\\Lambda$CDM model, and the IGM portion of the baryon energy density $\\Omega_b f_{\\rm IGM}$) can be independently measured thr...
13. Study of correlation between ultraluminous X-ray sources and their host galaxies
Priajana, I. G. P. M.; Wulandari, H. R. T.
2016-11-01
Ultraluminous X-ray sources (ULXs) are defined as non-nuclear point-source objects with apparent X-ray luminosities, Lx > 2×1039 erg s-1, in the 0.3-8 keV band. ULXs are often explained using two different scenarios, (1) ULXs as intermediate mass black hole (IMBH) with sub-Eddington accretion and (2) ULXs as stellar mass black hole with super-Eddington accretion. There are two methods that commonly used to study the characteristics of ULXs. One method is to study the X-ray spectra of ULXs, to determine the characteristics of their accretion flows from fitting their spectra using available spectral models. The other method is to investigate how population of ULXs correlate with their environment, in this case their host galaxies. Our goal is to find correlation between ULXs and the properties of its host galaxies, for example with Star Formation Rate (SFR), mass and morphology. From this study we found a positive correlation between ULXs number and SFR. From X-ray luminosity function, we found upper limit of black holes mass that power ULXs is about 100 M⊙.
14. Late time observations of GRB080319B: jet break, host galaxy and accompanying supernova
Tanvir, Nial R; Levan, Andrew; Fruchter, Andrew; Granot, Jonathan; Svensson, Karl M; O'Brien, Paul T; Wiersema, Klaas; Starling, Rhaana L C; Jakobsson, Pall; Fynbo, Johan; Hjorth, Jens; Curran, Peter; van der Horst, Alexander J; Kouveliotou, Chryssa; Racusin, Judith L; Burrows, David N; Genet, Frank
2008-01-01
The Swift-discovered GRB080319B was by far the most distant source ever observed at naked eye brightness, reaching a peak magnitude of 5.3 at a redshift of z=0.937. We present our late time optical and X-ray observations, which confirm that an achromatic break occurred in the power-law afterglow light curve at ~10^6 s post-burst. This most likely indicates that the gamma-ray burst (GRB) outflow was collimated, which for a uniform jet would imply a total energy in the jet E_{jet} \\gsim 10^{52.5} erg. Our observations also show a late-time excess of red light, which is well explained if the GRB was accompanied by a supernova, similar to those seen in some other long-duration GRBs. The latest observations are dominated by light from the host and show that the GRB took place in a faint dwarf galaxy (r(AB) = 27.2, rest-frame M_B = -17.3). This galaxy is small even by the standards of other GRB hosts, which is suggestive of a low metallicity environment.
15. Far-infrared observations of an unbiased sample of gamma-ray burst host galaxies
Kohn, Saul A; Bourne, Nathan; Baes, Maarten; Fritz, Jacopo; Cooray, Asantha; De Looze, Ilse; De Zotti, Gianfranco; Dannerbauer, Helmut; Dunne, Loretta; Dye, Simon; Eales, Stephen; Furlanetto, Cristina; Gonzalez-Nuevo, Joaquin; Ibar, Edo; Ivison, Rob J; Maddox, Steve J; Scott, Douglas; Smith, Daniel J B; Smith, Matthew W L; Symeonidis, Myrto; Valiante, Elisabetta
2015-01-01
Gamma-ray bursts (GRBs) are the most energetic phenomena in the Universe; believed to result from the collapse and subsequent explosion of massive stars. Even though it has profound consequences for our understanding of their nature and selection biases, little is known about the dust properties of the galaxies hosting GRBs. We present analysis of the far-infrared properties of an unbiased sample of 21 GRB host galaxies (at an average redshift of $z\\,=\\,3.1$) located in the {\\it Herschel} Astrophysical Terahertz Large Area Survey (H-ATLAS), the {\\it Herschel} Virgo Cluster Survey (HeViCS), the {\\it Herschel} Fornax Cluster Survey (HeFoCS), the {\\it Herschel} Stripe 82 Survey (HerS) and the {\\it Herschel} Multi-tiered Extragalactic Survey (HerMES), totalling $880$ deg$^2$, or $\\sim 3$\\% of the sky in total. Our sample selection is serendipitous, based only on whether the X-ray position of a GRB lies within a large-scale {\\it Herschel} survey -- therefore our sample can be considered completely unbiased. Using ...
16. The influence of host galaxy morphology on the properties of Type Ia supernovae from the JLA compilation
Henne, V.; Pruzhinskaya, M. V.; Rosnet, P.; Léget, P.-F.; Ishida, E. E. O.; Ciulli, A.; Gris, P.; Says, L.-P.; Gangler, E.
2017-02-01
The observational cosmology with distant Type Ia supernovae (SNe) as standard candles claims that the Universe is in accelerated expansion, caused by a large fraction of dark energy. In this paper we investigate the SN Ia environment, studying the impact of the nature of their host galaxies on the Hubble diagram fitting. The supernovae (192 SNe) used in the analysis were extracted from Joint-Light-curves-Analysis (JLA) compilation of high-redshift and nearby supernovae which is the best one to date. The analysis is based on the empirical fact that SN Ia luminosities depend on their light curve shapes and colors. We confirm that the stretch parameter of Type Ia supernovae is correlated with the host galaxy type. The supernovae with lower stretch are hosted mainly in elliptical and lenticular galaxies. No significant correlation between SN Ia colour and host morphology was found. We also examine how the luminosities of SNe Ia change depending on host galaxy morphology after stretch and colour corrections. Our results show that in old stellar populations and low dust environments, the supernovae are slightly fainter. SNe Ia in elliptical and lenticular galaxies have a higher α (slope in luminosity-stretch) and β (slope in luminosity-colour) parameter than in spirals. However, the observed shift is at the 1-σ uncertainty level and, therefore, can not be considered as significant. We confirm that the supernova properties depend on their environment and that the incorporation of a host galaxy term into the Hubble diagram fit is expected to be crucial for future cosmological analyses.
17. Attenuation of TeV γ-rays by the starlight photon field of the host galaxy
Zacharias, Michael; Chen, Xuhui; Wagner, Stefan J.
2017-03-01
The absorption of TeV γ-ray photons produced in relativistic jets by surrounding soft photon fields is a long-standing problem of jet physics. In some cases, the most likely emission site close to the central black hole is ruled out because of the high opacity caused by strong optical and infrared photon sources, such as the broad-line region. Mostly neglected for jet modelling is the absorption of γ-rays in the starlight photon field of the host galaxy. Analysing the absorption for arbitrary locations and observation angles of the γ-ray emission site within the host galaxy, we find that the distance to the galaxy centre, the observation angle, and the distribution of starlight in the galaxy are crucial for the amount of absorption. We derive the absorption value for a sample of 20 TeV-detected blazars with a redshift zr host properties, such as starlight emissivity, galactic size, half-light radius, and redshift. While the uncertainty of the spectral properties of the extragalactic background light exceeds the effect of absorption by stellar light from the host galaxy in distant objects, the latter is a dominant effect in nearby sources. It may also be revealed in a differential comparison of sources with similar redshifts.
18. Spectroscopic confirmation of a redshift 1.55 supernova host galaxy from the Subaru Deep Field Supernova Survey
Frederiksen, Teddy F; Hjorth, Jens; Maoz, Dan; Poznanski, Dovi
2012-01-01
The Subaru Deep Field (SDF) Supernova Survey discovered 10 Type Ia supernovae (SNe Ia) in the redshift range $1.5host galaxies. However, photometric redshifts might be biased, and the SN sample could be contaminated by active galactic nuclei (AGNs). Unfortunately, measuring spectroscopic redshifts of galaxies in the "redshift desert" 1.5 < z < 2.0 is hard because any prominent emission lines get shifted out of the optical and into the near infrared. Here we report the first robust redshift measurement and classification of hSDF0705.25, an SDF SN Ia host galaxy. Using the X-shooter spectrograph on the Very Large Telescope, we measure a spectroscopic redshift of 1.5456 +/- 0.0003, consistent with its photometric redshift of 1.552 +/- 0.018. From the strong emission-line spectrum we are able to rule out AGN activity and show that the SN host galaxy is a low-metallicity, star-burst dwarf galaxy, similar to typical SN Ia hosts at lower red... 19. Taking stock of superluminous supernovae and long gamma-ray burst host galaxy comparison using a complete sample of LGRBs Japelj, J.; Vergani, S. D.; Salvaterra, R.; Hunt, L. K.; Mannucci, F. 2016-10-01 Long gamma-ray bursts (LGRBs) and superluminous supernovae (SLSNe) are both explosive transients with very massive progenitor stars. Clues about the nature of the progenitors can be found by investigating environments in which such transients occur. While studies of LGRB host galaxies have a long history, dedicated observational campaigns have only recently resulted in a high enough number of photometrically and spectroscopically observed SLSN hosts to allow statistically significant analysis of their properties. In this paper we make a comparison of the host galaxies of hydrogen-poor (H-poor) SLSNe and the Swift/BAT6 sample of LGRBs. In contrast to previous studies, we use a complete sample of LGRBs and we pay special attention to the comparison methodology and the selection of SLSN sample whose data have been compiled from the available literature. At intermediate redshifts (0.3 < z < 0.7) the two classes of transients select galaxies whose properties (stellar mass, luminosity, star formation rate, specific star formation rate and metallicity) do not differ significantly. Moreover, the host galaxies of both classes of objects follow the fundamental metallicity relation and the fundamental plane of metallicity. In contrast to previous studies we show that at intermediate redshifts the emission line equivalent widths of the two populations are essentially the same and that the previous claims regarding the higher fraction of SLSN hosts among the extreme emission line galaxies with respect to LGRBs are mostly due to a larger fraction of strong-line emitters among SLSN hosts at z < 0.3, where samples of LGRB hosts are small and poorly defined. 20. Hydrogen-poor superluminous supernovae and long-duration gamma-ray bursts have similar host galaxies Lunnan, R.; Chornock, R.; Berger, E.; Laskar, T.; Fong, W.; Sanders, N. E.; Challis, P. M.; Drout, M. R.; Foley, R. J.; Kirshner, R. P.; Leibler, C.; Marion, G. H.; Milisavljevic, D.; Narayan, G. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Rest, A. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Huber, M. E. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); McCrum, M.; Smartt, S. J.; Smith, K. W. [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Scolnic, D., E-mail: [email protected] [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); and others 2014-06-01 We present optical spectroscopy and optical/near-IR photometry of 31 host galaxies of hydrogen-poor superluminous supernovae (SLSNe), including 15 events from the Pan-STARRS1 Medium Deep Survey. Our sample spans the redshift range 0.1 ≲ z ≲ 1.6, and is the first comprehensive host galaxy study of this specific subclass of cosmic explosions. Combining the multi-band photometry and emission-line measurements, we determine the luminosities, stellar masses, star formation rates, and metallicities. We find that, as a whole, the hosts of SLSNe are a low-luminosity ((M{sub B} ) ≈ –17.3 mag), low stellar mass ((M {sub *}) ≈ 2 × 10{sup 8} M {sub ☉}) population, with a high median specific star formation rate ((sSFR) ≈ 2 Gyr{sup –1}). The median metallicity of our spectroscopic sample is low, 12 + log (O/H) ≈ 8.35 ≈ 0.45 Z {sub ☉}, although at least one host galaxy has solar metallicity. The host galaxies of H-poor SLSNe are statistically distinct from the hosts of GOODS core-collapse SNe (which cover a similar redshift range), but resemble the host galaxies of long-duration gamma-ray bursts (LGRBs) in terms of stellar mass, SFR, sSFR, and metallicity. This result indicates that the environmental causes leading to massive stars forming either SLSNe or LGRBs are similar, and in particular that SLSNe are more effectively formed in low metallicity environments. We speculate that the key ingredient is large core angular momentum, leading to a rapidly spinning magnetar in SLSNe and an accreting black hole in LGRBs. 1. The influence of host galaxy morphology on the properties of Type Ia supernovae from the JLA compilation Henne, Vincent; Rosnet, Philippe; Leget, Pierre-Francois; Ishida, Emille; Ciulli, Alexandre; Gris, Philippe; Says, Louis-Pierre; Gangler, Emmanuel 2016-01-01 The observational cosmology with distant Type Ia supernovae (SNe) as standard candles claims that the Universe is in accelerated expansion, caused by a large fraction of dark energy. In this paper we investigate the SN Ia environment, studying the impact of the nature of their host galaxies on the Hubble diagram fitting. The supernovae (192 SNe) used in the analysis were extracted from Joint-Light-curves-Analysis (JLA) compilation of high-redshift and nearby supernovae which is the best one to date. The analysis is based on the empirical fact that SN Ia luminosities depend on their light curve shapes and colors. We confirm that the stretch parameter of Type Ia supernovae is correlated with the host galaxy type. The supernovae with lower stretch are hosted mainly in elliptical and lenticular galaxies. No significant correlation between SN Ia colour and host morphology was found. We also examine how the luminosities of SNe Ia change depending on host galaxy morphology after stretch and colour corrections. Our r... 2. Star formation in z>1 3CR host galaxies as seen by Herschel Podigachoski, P; Haas, M; Leipski, C; Wilkes, B; Kuraszkiewicz, J; Westhues, C; Willner, S P; Ashby, M L N; Chini, R; Clements, D L; Fazio, G G; Labiano, A; Lawrence, C; Meisenheimer, K; Peletier, R F; Siebenmorgen, R; Kleijn, G Verdoes 2015-01-01 We present Herschel (PACS and SPIRE) far-infrared (FIR) photometry of a complete sample of z>1 3CR sources, from the Herschel GT project The Herschel Legacy of distant radio-loud AGN (PI: Barthel). Combining these with existing Spitzer photometric data, we perform an infrared (IR) spectral energy distribution (SED) analysis of these landmark objects in extragalactic research to study the star formation in the hosts of some of the brightest active galactic nuclei (AGN) known at any epoch. Accounting for the contribution from an AGN-powered warm dust component to the IR SED, about 40% of our objects undergo episodes of prodigious, ULIRG-strength star formation, with rates of hundreds of solar masses per year, coeval with the growth of the central supermassive black hole. Median SEDs imply that the quasar and radio galaxy hosts have similar FIR properties, in agreement with the orientation-based unification for radio-loud AGN. The star-forming properties of the AGN hosts are similar to those of the general popul... 3. Host galaxies of double-peaked [OIII] emitting AGN: binary AGN or mergers? Villforth, Carolin 2013-01-01 Mergers are suspected to be reliable triggers of both starformation and AGN activity. However, the exact timing of this process remains poorly understood. Here, we present deep imaging and long slit spectroscopy data of a sample of four double-peaked [OIII] emitting AGN. These sources are often believed to host binary AGN, or at least be currently undergoing major mergers. The sample presented here either have previous IFU and high resolution imaging data that show double-nuclei in the IR as well as kinematicly and spatially distinct line emitting regions. Two sources have detections of double point sources in either the X-ray or radio. The sources studied are therefore likely binary AGN. The AGN in this sample are luminous, radio-quiet and at low redshift. The$u/r/zimaging data show host galaxies in a wide range of merger stages, with the majority (3/4) showing tidal tails or complex kinematics and morphologies clearly indicating a recent merger. One source however -hosting a double X-ray source- shows qu... 4. The low-extinction afterglow in the solar-metallicity host galaxy of GRB 110918A Elliott, J; Greiner, J; Savaglio, S; E., F Olivares; Rau, A; Postigo, A de Ugarte; Sánchez-Ramírez, R; Wiersema, K; Schady, P; Kann, D A; Filgas, R; Nardini, M; Berger, E; Fox, D; Gorosabel, J; Klose, S; Levan, A; Guelbenzu, A Nicuesa; Rossi, A; Schmidl, S; Sudilovsky, V; Tanvir, N R; Thöne, C C 2013-01-01 Galaxies selected through long gamma-ray bursts (GRBs) could be of fundamental importance when mapping the star formation history out to the highest redshifts. Before using them as efficient tools in the early Universe, however, the environmental factors that govern the formation of GRBs need to be understood. Metallicity is theoretically thought to be a fundamental driver in GRB explosions and energetics, but is still, even after more than a decade of extensive studies, not fully understood. This is largely related to two phenomena: a dust-extinction bias, that prevented high-mass and thus likely high-metallicity GRB hosts to be detected in the first place, and a lack of efficient instrumentation, that limited spectroscopic studies including metallicity measurements to the low-redshift end of the GRB host population. The subject of this work is the very energetic GRB 110918A, for which we measure one of the largest host-integrated metallicities, ever, and the highest stellar mass for z<1.9. This presents ... 5. The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements. II. The Full Sample of Reverberation-Mapped AGNs Bentz, Misty C.; Peterson, Bradley M.; Netzer, Hagai 2009-01-01 We present high-resolution Hubble Space Telescope images of all 35 active galactic nuclei (AGNs) with optical reverberation-mapping results, which we have modeled to create a nucleus-free image of each AGN host galaxy. From the nucleus-free images, we determine the host-galaxy contribution... 6. The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements. II. The Full Sample of Reverberation-Mapped AGNs Bentz, Misty C.; Peterson, Bradley M.; Netzer, Hagai 2009-01-01 We present high-resolution Hubble Space Telescope images of all 35 active galactic nuclei (AGNs) with optical reverberation-mapping results, which we have modeled to create a nucleus-free image of each AGN host galaxy. From the nucleus-free images, we determine the host-galaxy contribution to gro... 7. First measurement of HI 21cm emission from a GRB host galaxy indicates a post-merger system Arabsalmani, Maryam; Zwaan, Martin; Kanekar, Nissim; Michałowski, Michał J 2015-01-01 We report the detection and mapping of atomic hydrogen in HI 21cm emission from ESO 184-G82, the host galaxy of the gamma ray burst 980425. This is the first instance where HI in emission has been detected from a galaxy hosting a gamma ray burst. ESO 184-G82 is an isolated galaxy and contains a Wolf-Rayet region close to the location of the gamma ray burst and the associated supernova, SN 1998bw. This is one of the most luminous HII regions identified in the local Universe, with a very high inferred density of star formation. The HI 21cm observations reveal a high HI mass for the galaxy, twice as large as the stellar mass. The spatial and velocity distribution of the HI 21cm emission reveals a disturbed rotating gas disk, which suggests that the galaxy has undergone a recent minor merger that disrupted its rotation. We find that the Wolf-Rayet region and the gamma ray burst are both located in the highest HI column density region of the galaxy. We speculate that the merger event has resulted in shock compress... 8. THE ACS VIRGO CLUSTER SURVEY. XVII. THE SPATIAL ALIGNMENT OF GLOBULAR CLUSTER SYSTEMS WITH EARLY-TYPE HOST GALAXIES Wang Qiushi; Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China); Blakeslee, John P.; Cote, Patrick; Ferrarese, Laura [Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Jordan, Andres [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Mei, Simona [University of Paris 7 Denis Diderot, F-75205 Paris Cedex 13 (France); West, Michael J., E-mail: [email protected] [Maria Mitchell Observatory, 4 Vestal Street, Nantucket, MA 02554 (United States) 2013-06-01 We study the azimuthal distribution of globular clusters (GCs) in early-type galaxies and compare them to their host galaxies using data from the ACS Virgo Cluster Survey. We find that in host galaxies with visible elongation ({epsilon} > 0.2) and intermediate to high luminosities (M{sub z} < -19), the GCs are preferentially aligned along the major axis of the stellar light. The red (metal-rich) GC subpopulations show strong alignment with the major axis of the host galaxy, which supports the notion that these GCs are associated with metal-rich field stars. The metal-rich GCs in lenticular galaxies show signs of being more strongly associated with disks rather than bulges. Surprisingly, we also find that the blue (metal-poor) GCs can also show the same correlation. If the metal-poor GCs are part of the early formation of the halo and built up through mergers, then our results support a picture where halo formation and merging occur anisotropically, and that the present-day major axis is an indicator of the preferred merging axis. 9. Near-infrared imaging of the host galaxies of three radio-loud quasars at z = 1.5 Falomo, R; Treves, A; Falomo, Renato; Kotilainen, Jari; Treves, Aldo 2000-01-01 We present high spatial resolution near-infrared H-band (1.65 microns) images, taken with ISAAC on UT1 of ESO VLT, of three radio-loud quasars at z = 1.5, as a pilot study for imaging of a larger sample of radio-loud and radio-quiet quasars in the redshift range 1 < z < 2. We are able to clearly detect the host galaxy in two quasars (PKS 0000-177 and PKS 0348-120) and marginally in the third (PKS 0402-362). The host galaxies appear compact (average bulge scale-length R(e) = 4 kpc) and luminous (average M(H) = -27.6+-0.1). They are 2.5 mag more luminous than the typical galaxy luminosity (M*(H) = -25.0+-0.2), and are comparable to the hosts of low redshift radio-loud quasars (M(H) = -26), taking into account passive stellar evolution. Their luminosities are also similar to those of high redshift radio galaxies. All three quasars have at least one close companion galaxy at a projected distance < 50 kpc from the quasar, assuming they are at the same redshift. 10. An evolutionary missing link? A modest-mass early-type galaxy hosting an over-sized nuclear black hole van Loon, Jacco Th 2015-01-01 SAGE1C\\,J053634.78-$722658.5 is a galaxy at redshift$z=0.14$, discovered behind the Large Magellanic Cloud in the {\\it Spitzer} Space Telescope "Surveying the Agents of Galaxy Evolution" Spectroscopy survey (SAGE-Spec). It has very strong silicate emission at 10$\\mu$m but negligible far-IR and UV emission. This makes it a candidate for a bare AGN source in the IR, perhaps seen pole-on, without significant IR emission from the host galaxy. In this paper we present optical spectra taken with the Southern African Large Telescope (SALT) to investigate the nature of the underlying host galaxy and its AGN. We find broad H$\\alpha$emission characteristic of an AGN, plus absorption lines associated with a mature stellar population ($>9$Gyr), and refine its redshift determination to$z=0.1428\\pm0.0001$. There is no evidence for any emission lines associated with star formation. This remarkable object exemplifies the need for separating the emission from any AGN from that of the host galaxy when employing infrared ... 11. A nearby GRB host galaxy: VLT/X-shooter observations of HG 031203 Guseva, N G; Fricke, K J; Henkel, C; 10.1051/0004-6361/201116765 2011-01-01 (abridged) Long-duration gamma-ray bursts (LGRBs) occur in galaxies of generally low metallicity. We aim at a spectroscopic analysis of HG 031203, the host galaxy of a LRGB burst, to obtain its properties. Based on VLT/X-shooter spectroscopic observations in the wavelength range 3200-24000A, we use standard direct methods to evaluate physical conditions and element abundances. The resolving power of the instrument also allowed us to trace the kinematics of the ionised gas. We derive an interstellar oxygen abundance of 12+logO/H=8.20+/-0.03. The observed fluxes of hydrogen lines correspond to the theoretical recombination values after correction for extinction with a single value C(Hbeta)=1.67. We produce the CLOUDY photoionisation HII region model that reproduces observed emission-line fluxes of different ions in the optical range. This model also predicts emission-line fluxes in the near-infrared (NIR) and mid-infrared (MIR) ranges that agree well with the observed ones. This implies that the star-forming re... 12. Nearby supernova host galaxies from the CALIFA Survey: I. Sample, data analysis, and correlation to star-forming regions Galbany, L; Mourão, A M; Rodrigues, M; Flores, H; García-Benito, R; Mast, D; Mendoza, M A; Sánchez, S F; Badenes, C; Barrera-Ballesteros, J; Bland-Hawthorn, J; Falcón-Barroso, J; García-Lorenzo, B; Gomes, J M; Delgado, R M González; Kehrig, C; Lyubenova, M; López-Sánchez, A R; de Lorenzo-Cáceres, A; Marino, R A; Meidt, S; Mollá, M; Papaderos, P; Pérez-Torres, M A; Rosales-Ortega, F F; van de Ven, G 2014-01-01 [Abridged] We use optical IFS of nearby SN host galaxies provided by the CALIFA Survey with the goal of finding correlations in the environmental parameters at the location of different SN types. We recover the sequence in association of different SN types to the star-forming regions by using several indicators of the ongoing and recent SF related to both the ionized gas and the stellar populations. While the total ongoing SF is on average the same for the three SN types, SNe Ibc/IIb tend to happen closer to star-forming regions and occur in higher SF density locations compared to SNe II and SNe~Ia, the latter showing the weakest correlation. SNe~Ia host galaxies have on average masses that are$\\sim$0.3-0.8~dex higher than CC SNe hosts due to a larger fraction of old stellar populations in the SNe~Ia hosts. Using the recent SN~Ia delay-time distribution and the SFHs of the galaxies, we show that the SN~Ia hosts in our sample should presently produce a factor 2 more SNe~Ia than the CC~SN hosts. Since both typ... 13. SUPPRESSION OF STAR FORMATION IN THE HOSTS OF LOW-EXCITATION RADIO GALAXIES Pace, Cameron; Salim, Samir, E-mail: [email protected], E-mail: [email protected] [Indiana University, Department of Astronomy, Swain Hall West 319, Bloomington, IN 47405-7105 (United States) 2016-02-10 The feedback from radio-loud active galactic nuclei (R-AGNs) may help maintain low star-formation (SF) rates in their early-type hosts, but the observational evidence for this mechanism has been inconclusive. We study systematic differences of aggregate spectral energy distributions (SEDs) of various subsets of ∼4000 low-redshift R-AGNs from Best and Heckman with respect to (currently) inactive control samples selected to have matching redshift, stellar mass, population age, axis ratio, and environment. Aggregate SEDs, ranging from the ultraviolet (UV) through mid-infrared (mid-IR, 22 μm), were constructed using a Bayesian method that eliminates biases from non-detections in Galaxy Evolution Explorer and Wide-field Infrared Survey Explorer. We study rare high-excitation sources separately from low-excitation ones, which we split by environment and host properties. We find that both the UV and mid-IR emission of non-cluster R-AGNs (80% of sample) are suppressed by ∼0.2 dex relative to that of the control group, especially for moderately massive galaxies (log M{sub *} ≲ 11). The difference disappears for high-mass R-AGNs and for R-AGNs in clusters, where other, non-AGN quenching/maintenance mechanisms may dominate, or where the suppression of SF due to AGNs may persist between active phases of the central engine, perhaps because of the presence of a hot gaseous halo storing AGN energy. High-excitation (high accretion rate) sources, which make up 2% of the R-AGN sample, do not show any evidence of SF suppression (their UV is the same as in controls), but they exhibit a strong mid-IR excess due to AGN dust heating. 14. A Method to Measure the Mass of Damped Ly-alpha Absorber Host Galaxies Using Fluctuations in 21cm Emission Wyithe, Stuart 2008-01-01 Observations of damped Ly-alpha absorbers (DLA) indicate that the fraction of hydrogen in its neutral form (HI) is significant by mass at all redshifts. This gas represents the reservoir of material that is available for star formation at late times. As a result, observational identification of the systems in which this neutral hydrogen resides is an important missing ingredient in models of galaxy formation. Precise identification of DLA host mass via traditional clustering studies is not practical owing to the small numbers of known systems being spread across sparsely distributed sight lines. However following the completion of reionization, 21cm surface brightness fluctuations will be dominated by neutral hydrogen in DLAs. Observations of these fluctuations will measure the combined clustering signal from all DLAs within a large volume. We show that measurement of the spherically averaged power-spectrum of 21cm intensity fluctuations due to DLAs could be used to measure the galaxy bias for DLA host galaxi... 15. Constraints on Black Hole/Host Galaxy Co-evolution and Binary Stalling Using Pulsar Timing Arrays Simon, Joseph 2016-01-01 Pulsar timing arrays are now setting increasingly tight limits on the gravitational wave background from binary supermassive black holes. But as upper limits grow more constraining, what can be implied about galaxy evolution? We investigate which astrophysical parameters have the largest impact on strain spectrum predictions and provide a simple framework to directly translate between measured values for the parameters of galaxy evolution and PTA limits on the gravitational wave background of binary supermassive black holes. We find that the most influential observable is the relation between a host galaxy's central bulge and its central black hole,$\\mbox{$M_{\\bullet}$-$M_{\\rm bulge}$}$, which has the largest effect on the mean value of the characteristic strain amplitude. However, the variance of each prediction is dominated by uncertainties in the galaxy stellar mass function. Using this framework with the best published PTA limit, we can set limits on the shape and scatter of the$\\mbox{$M_{\\bullet}$-$M_{... 16. Evidence of suppression of star formation by quasar-driven winds in gas-rich host galaxies at z < 1? Wylezalek, Dominika; Zakamska, Nadia L. 2016-10-01 Feedback from active galactic nuclei (AGN) is widely considered to be the main driver in regulating the growth of massive galaxies through heating or driving gas out of the galaxy, preventing further increase in stellar mass. Observational proof for this scenario has, however, been scarce. We have assembled a sample of 132 radio-quiet type-2 and red AGN at 0.1 < z < 1. We measure the kinematics of the AGN-ionized gas, the host galaxies' stellar masses and star formation rates (SFRs) and investigate the relationships between AGN luminosities, specific star formation rates (sSFRs) and outflow strengths W90 - the 90 per cent velocity width of the [O III]λ5007Å line power and a proxy for the AGN-driven outflow speed. Outflow strength is independent of sSFR for AGN selected on their mid-IR luminosity, in agreement with previous work demonstrating that star formation is not sufficient to produce the observed ionized gas outflows which have to be powered by AGN activity. More importantly, we find a negative correlation between W90 and sSFR in the AGN hosts with the highest SFRs, i.e. with the highest gas content, where presumably the coupling of the AGN-driven wind to the gas is strongest. This implies that AGN with strong outflow signatures are hosted in galaxies that are more quenched' than galaxies with weaker outflow signatures. Despite the galaxies' high SFRs, we demonstrate that the outflows are not star formation driven but indeed due to AGN powering. This observation is consistent with the AGN having a net suppression, negative' impact, through feedback on the galaxies' star formation history. 17. The host galaxies and narrow-line regions of four double-peaked [OIII] AGNs Villforth, Carolin; Hamann, Fred [Department of Astronomy, University of Florida, 32611 Gainesville, FL (United States) 2015-03-01 Major gas-rich mergers of galaxies are expected to play an important role in triggering and fueling luminous active galactic nuclei (AGNs). The mechanism of AGN fueling during mergers, however, remains poorly understood. We present deep multi-band (u/r/z) imaging and long-slit spectroscopy of four double-peaked [OIII] emitting AGNs. This class of object is likely associated with either kiloparsec-separated binary AGNs or final stage major mergers, although AGNs with complex narrow-line regions (NLRs) are known contaminants. Such objects are of interest since they represent the onset of AGN activity during the merger process. Three of the four double-peaked [OIII] emitters studied have been confirmed as major mergers using near-infrared imaging and one is a confirmed X-ray binary AGN. All AGNs are luminous, radio-quiet to radio-intermediate, and have redshifts of 0.1host morphologies and tidal features, while the remaining source is morphologically undisturbed down to low surface brightness limits (∼27 mag arcsec{sup −2} in r). The lack of morphological disturbances in this galaxy despite the fact that it is a close binary AGN suggests that the merger of a binary black hole can take longer than 1 Gyr. All AGNs hosted by merging galaxies have companions at distances ⩽150 kpc. The NLRs have large sizes (10 kpc < r < 100 kpc) and consist of compact clumps with considerable relative velocities between components (∼200–650 km s{sup −1}). We detect broad, predominantly blue, wings with velocities up to ∼1500 km s{sup −1} in [OIII], indicative of powerful outflows. The outflows are compact (<5 kpc) and co-spatial with nuclear regions showing considerable reddening, consistent with enhanced star formation. One source shows an offset between gas and stellar kinematics, consistent with either a bipolar flow or a counter-rotating gas disk. In all other sources, the ionized gas 18. A glimpse at quasar host galaxy far-UV emission using damped Lyα's as natural coronagraphs Cai, Zheng; Fan, Xiaohui; Wang, Ran; McGreer, Ian, E-mail: [email protected] [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Noterdaeme, Pasquier; Finley, Hayley; Petitjean, Patrick [Institut d' Astrophysique de Paris, CNRS-UPMC, UMR7095, 98bis bd Arago, F-75014 Paris (France); Carithers, Bill [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA (United States); Bian, Fuyan [Research School of Astronomy and Astrophysics, Australian National University, Canberra, Weston Creek, ACT, 2611 (Australia); Miralda-Escudé, Jordi [Institució Catalana de Recerca i Estudis Avançats, Barcelona (Spain); Pâris, Isabelle [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Zakamska, Nadia L. [Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218 (United States); Ge, Jian [Department of Astronomy, University of Florida, Gainesville, FL (United States); Slosar, Anze [Brookhaven National Laboratory, Upton, NY 11973 (United States) 2014-10-01 In merger-driven models of massive galaxy evolution, the luminous quasar phase is expected to be accompanied by vigorous star formation in quasar host galaxies. In this paper, we use high column density damped Lyα (DLA) systems along quasar sight lines as natural coronagraphs to directly study the far-UV (FUV) radiation from the host galaxies of luminous background quasars. We have stacked the spectra of ∼2000 DLA systems (N {sub H} {sub I} > 10{sup 20.6} cm{sup –2}) with a median absorption redshift (z) = 2.6 selected from quasars observed in the SDSS-III Baryon Oscillation Spectroscopic Survey. We detect residual flux in the dark troughs of the composite DLA spectra. The level of this residual flux significantly exceeds systematic errors in the Sloan Digital Sky Survey fiber sky subtraction; furthermore, the residual flux is strongly correlated with the continuum luminosity of the background quasar, while uncorrelated with DLA column density or metallicity. We conclude that the flux could be associated with the average FUV radiation from the background quasar host galaxies (with medium redshift (z) = 3.1) that is not blocked by the intervening DLA. Assuming that all of the detected flux originates from quasar hosts, for the highest quasar luminosity bin ((L) = 2.5 × 10{sup 13} L {sub ☉}), the host galaxy has an FUV intensity of 1.5 ± 0.2 × 10{sup 40} erg s{sup –1} Å{sup –1}; this corresponds to an unobscured UV star formation rate of 9 M {sub ☉} yr{sup –1}. 19. Driving the Growth of the Earliest Supermassive Black Holes with Major Mergers of Host Galaxies Tanaka, Takamitsu L 2014-01-01 The formation mechanism of supermassive black holes (SMBHs) in general, and of$\\sim 10^9\\,{\\rm M}_{\\odot}$SMBHs observed as luminous quasars at redshifts$z> 6$in particular, remains an open fundamental question. The presence of such massive BHs at such early times, when the Universe was less than a billion years old, implies that they grew via either super-Eddington accretion, or nearly uninterrupted gas accretion near the Eddington limit; the latter, at first glance, is at odds with empirical trends at lower redshifts, where quasar episodes associated with rapid BH growth are rare and brief. In this work, I examine whether and to what extent the growth of the$z> 6$quasar SMBHs can be explained within the standard quasar paradigm, in which major mergers of host galaxies trigger episodes of rapid gas accretion below or near the Eddington limit. Using a suite of Monte Carlo merger tree simulations of the assembly histories of the likely hosts of the$z> 6$quasars, I investigate (i) their growth and major... 20. Nearby supernova host galaxies from the CALIFA Survey: II. SN environmental metallicity Galbany, L; Mourão, A M; Rodrigues, M; Flores, H; Walcher, C J; Sánchez, S F; García-Benito, R; Mast, D; Badenes, C; Delgado, R M González; Kehrig, C; Lyubenova, M; Marino, R A; Mollá, M; Meidt, S; Pérez, E; van de Ven, G; Vílchez, J M 2016-01-01 The metallicity of a supernova (SN) progenitor, together with its mass, is one of the main parameters that rules their outcome. We present a metallicity study of 115 nearby SN host galaxies (0.00510 dex) by targeted searches. We also found no evidence that the metallicity at the SN location differs from the average metallicity at the GCD of the SNe. By extending our SN sample with published metallicities at the SN location, we studied the metallicity distributions for all SN subtypes split into SN discovered in targeted and untargeted searches. We confirm a bias toward higher host masses and metallicities in the targeted searches. Combining data from targeted and untargeted searches we found a sequence from higher to lower local metallicity: SN Ia, Ic, and II show the highest metallicity, which is significantly higher than SN Ib, IIb, and Ic-BL. Our results support the picture of SN Ib resulting from binary progenitors and, at least part of, SN Ic being the result of single massive stars stripped of their out... 1. Hubble Space Telescope observations of the host galaxies and environments of calcium-rich supernovae Lyman, J D; James, P A; Angus, C R; Church, R P; Davies, M B; Tanvir, N R 2016-01-01 Calcium-rich supernovae represent a significant challenge for our understanding of the fates of stellar systems. They are less luminous than other supernova (SN) types and they evolve more rapidly to reveal nebular spectra dominated by strong calcium lines with weak or absent signatures of other intermediate- and iron-group elements, which are seen in other SNe. Strikingly, their explosion sites also mark them out as distinct from other SN types. Their galactocentric offset distribution is strongly skewed to very large offsets (around one third are offset greater than 20 kpc), meaning they do not trace the stellar light of their hosts. Many of the suggestions to explain this extreme offset distribution have invoked the necessity for unusual formation sites such as globular clusters or dwarf satellite galaxies, which are therefore difficult to detect. Building on previous work attempting to detect host systems of nearby Ca-rich SNe, we here present Hubble Space Telescope imaging of 5 members of the class - 3 e... 2. The host galaxies of core-collapse supernovae and gamma ray bursts Svensson, K M; Tanvir, N R; Fruchter, A S; Strolger, L -G 2010-01-01 We present a comparative study of the galactic and small scale environments of gamma-ray bursts (GRB) and core collapse supernovae (CCSN). We use a sample of 34 GRB hosts at z<1.2, and a comparison sample of 58 supernova hosts located within the Great Observatories Origins Deep Survey footprint. We fit template spectra to the available photometric data, which span the range 0.45-24 micron, and extract absolute magnitudes, stellar masses and star formation rates from the resulting fits. Our results broadly corroborate previous findings, but offer significant enhancements in spectral coverage and a factor 2-3 increase in sample size. Specifically, we find that CCSN occur frequently in massive spirals (spiral fraction ~50%). In contrast GRBs occur in small, relatively low mass galaxies with high specific and surface star formation rates, and have a spiral fraction of only ~10%. A comparison of the rest frame absolute magnitudes of the GRB and CCSN sample is less conclusive than found in previous work, suggest... 3. Bright [CII] and dust emission in three z>6.6 quasar host galaxies observed by ALMA Venemans, B P; Zschaechner, L; Decarli, R; De Rosa, G; Findlay, J R; McMahon, R G; Sutherland, W J 2015-01-01 We present ALMA detections of the [CII] 158 micron emission line and the underlying far-infrared continuum of three quasars at 6.6~6 quasar hosts correlate with the quasar's bolometric luminosity. In one quasar, the [CII] line is significantly redshifted by ~1700 km/s with respect to the MgII broad emission line. Comparing to values in the literature, we find that, on average, the MgII is blueshifted by 480 km/s (with a standard deviation of 630 km/s) with respect to the host galaxy redshift, i.e. one of our quasars is an extreme outlier. Through modeling we can rule out a flat rotation curve for our brightest [CII] emitter. Finally, we find that the ratio of black hole mass to host galaxy (dynamical) mass is higher by a factor 3-4 (with significant scatter) than local relations. 4. Attenuation of TeV$\\gamma$-rays by the starlight photon field of the host galaxy Zacharias, Michael; Wagner, Stefan J 2016-01-01 The absorption of TeV$\\gamma$-ray photons produced in relativistic jets by surrounding soft photon fields is a long-standing problem of jet physics. In some cases the most likely emission site close to the central black hole is ruled out because of the high opacity caused by strong optical and infrared photon sources, such as the broad line region. Mostly neglected for jet modeling is the absorption of$\\gamma$-rays in the starlight photon field of the host galaxy. Analyzing the absorption for arbitrary locations and observation angles of the$\\gamma$-ray emission site within the host galaxy we find that the distance to the galaxy center, the observation angle, and the distribution of starlight in the galaxy are crucial for the amount of absorption. We derive the absorption value for a sample of$20$TeV detected blazars with a redshift$z_r<0.2$. The absorption value of the$\\gamma$-ray emission located in the galaxy center may be as high as$20\\%$with an average value of$6\\%$. This is important in ord... 5. The Contribution of Host Galaxies to the Infrared Energy Output of$z\\gtrsim5.0$QUASARS Lyu, Jianwei; Alberts, Stacey 2015-01-01 The infrared spectral energy distributions (SEDs) of$z\\gtrsim 5$quasars can be reproduced by combining a low-metallicity galaxy template with a standard AGN template. The host galaxy is represented by Haro 11, a compact, moderately low metallicity, star-bursting galaxy that shares typical features of high-$z$galaxies. For the vast majority of$z\\gtrsim 5$quasars, the AGN contribution is well modeled by a standard empirical template with the contamination of star formation in the infrared subtracted. Together, these two templates can separate the contributions from the host galaxy and the AGN even in the case of limited data points, given that this model has only two free parameters. Using this method, we re-analyze 69$z\\gtrsim 5$quasars with extensive Herschel observations, and derive their AGN luminosities$L_{\\rm AGN}$in a range$\\sim (0.78-27.4) \\times10^{13}\\, L_{\\odot}$, the infrared luminosities from star formation$L_{\\rm SF,IR} \\sim (<1.5-25.7)\\times10^{12}\\, L_{\\odot}$, and the correspondin... 6. ALMA Observations of the Host Galaxy of GRB090423 at z=8.23: Deep Limits on Obscured Star Formation 630 Million Years After the Big Bang Berger, E; Chary, R -R; Laskar, T; Chornock, R; Tanvir, N R; Stanway, E R; Levan, A J; Levesque, E M; Davies, J E 2014-01-01 We present rest-frame far-infrared (FIR) and optical observations of the host galaxy of GRB090423 at z=8.23 from the Atacama Large Millimeter Array (ALMA) and the Spitzer Space Telescope, respectively. The host remains undetected to 3-sigma limits of Fnu(222 GHz)4 (Lyman break galaxies, Ly-alpha emitters, and submillimeter galaxies), and find that our limit on the FIR luminosity is the most constraining to date, although the field galaxies have much larger rest-frame UV/optical luminosities than the host of GRB090423 by virtue of their selection techniques. We conclude that GRB host galaxies at z>4, especially those with measured interstellar medium metallicities from afterglow spectroscopy, are an attractive sample for future ALMA studies of high redshift obscured star formation. 7. Supermassive black holes in disc-dominated galaxies outgrow their bulges and co-evolve with their host galaxies Simmons, B. D.; Smethurst, R. J.; Lintott, C. 2017-09-01 The deep connection between galaxies and their supermassive black holes is central to modern astrophysics and cosmology. The observed correlation between galaxy and black hole mass is usually attributed to the contribution of major mergers to both. We make use of a sample of galaxies whose disc-dominated morphologies indicate a major-merger-free history and show that such systems are capable of growing supermassive black holes at rates similar to quasars. Comparing black hole masses to conservative upper limits on bulge masses, we show that the black holes in the sample are typically larger than expected if processes creating bulges are also the primary driver of black hole growth. The same relation between black hole and total stellar mass of the galaxy is found for the merger-free sample as well as a sample that has experienced substantial mergers, indicating that major mergers do not play a significant role in controlling the co-evolution of galaxies and black holes. We suggest that more fundamental processes that contribute to galaxy assembly are also responsible for black hole growth. 8. Gamma-ray burst afterglows as probes of their host galaxies and the cosmos Cucchiara, Antonino 2010-12-01 Gamma-ray Bursts (GRBs) represent the sole class of catastrophic phenomena seen over almost the entire history of the Universe. Their extreme luminosities in high energy gamma-ray radiation make them readily detectable, even with relatively small satellite-based detectors, out to the earliest cosmic epochs. Moreover, the brilliance of their fading afterglow light, routinely observed in X-ray, optical, near-infrared, and radio wavelengths, allows them to be exploited -- for hours, days, or weeks -- as cosmic lighthouses, probing the conditions of gas and dust along the line of sight, through their host galaxies and the cosmos at large. Since the November 2004 launch of Swift, this GRB-focused NASA mission has discovered more than 500 GRBs, in almost all cases reporting the burst coordinates to ground-based observers within seconds of the event. The availability of prompt burst positions from Swift, combined with promptly-reported flux measurements from instruments on Swift and an array of ground-based robotic telescopes, have enabled targeted spectroscopic campaigns that have gathered detailed observations of the young, bright afterglows of hundreds of these events. This thesis reports the results of my own efforts over the past 5 years, analyzing imaging and spectroscopic observations of Swift-detected GRBs as triggered according to my own requests, or as gathered from public data archives. In Chapter 2, I discuss our follow-up campaign for GRB090429B, one of our best "extreme redshift" (z > 8) candidates. This burst followed closely on the spectroscopicallyconfirmed z = 8.2 GRB090423, and our multiwavelength observations and SED modeling demonstrate the value and limitation of such studies, in cases where a spectroscopic redshift cannot be gathered in a timely fashion. I also address the importance of such extreme-redshift events from a cosmological perspective. In Chapter 3, I use high-resolution GRB afterglow spectra to study the properties of intervening 9. Spatially Resolved Patchy Lyα Emission within the Central Kiloparsec of a Strongly Lensed Quasar Host Galaxy at z = 2.8 Bayliss, Matthew B.; Sharon, Keren; Acharyya, Ayan; Gladders, Michael D.; Rigby, Jane R.; Bian, Fuyan; Bordoloi, Rongmon; Runnoe, Jessie; Dahle, Hakon; Kewley, Lisa; Florian, Michael; Johnson, Traci; Paterno-Mahler, Rachel 2017-08-01 We report the detection of extended Lyα emission from the host galaxy of SDSS J2222+2745, a strongly lensed quasar at z = 2.8. Spectroscopic follow-up clearly reveals extended Lyα in emission between two images of the central active galactic nucleus (AGN). We reconstruct the lensed quasar host galaxy in the source plane by applying a strong lens model to HST imaging and resolve spatial scales as small as ˜200 pc. In the source plane, we recover the host galaxy morphology to within a few hundred parsecs of the central AGN and map the extended Lyα emission to its physical origin on one side of the host galaxy at radii ˜0.5-2 kpc from the central AGN. There are clear morphological differences between the Lyα and rest-frame ultraviolet stellar continuum emission from the quasar host galaxy. Furthermore, the relative velocity profiles of quasar Lyα, host galaxy Lyα, and metal lines in outflowing gas reveal differences in the absorbing material affecting the AGN and host galaxy. These data indicate the presence of patchy local intervening gas in front of the central quasar and its host galaxy. This interpretation is consistent with the central luminous quasar being obscured across a substantial fraction of its surrounding solid angle, resulting in strong anisotropy in the exposure of the host galaxy to ionizing radiation from the AGN. This work demonstrates the power of strong-lensing-assisted studies to probe spatial scales that are currently inaccessible by other means. 10. GEMINI SPECTROSCOPY OF THE SHORT-HARD GAMMA-RAY BURST GRB 130603B AFTERGLOW AND HOST GALAXY Cucchiara, A.; Prochaska, J. X.; Werk, J. [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Perley, D.; Cao, Y. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Blvd, Pasadena, CA 91125 (United States); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD (United States); Cardwell, A.; Turner, J. [Gemini South Observatory, AURA, Casilla 603, La Serena (Chile); Bloom, J. S. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Cobb, B. E., E-mail: [email protected] [The George Washington University, Washington, DC (United States) 2013-11-10 We present early optical photometry and spectroscopy of the afterglow and host galaxy of the bright short-duration gamma-ray burst GRB 130603B discovered by the Swift satellite. Using our Target of Opportunity program on the Gemini South telescope, our prompt optical spectra reveal a strong trace from the afterglow superimposed on continuum and emission lines from the z = 0.3568 ± 0.0005 host galaxy. The combination of a relatively bright optical afterglow (r' = 21.52 at Δt = 8.4 hr), together with an observed offset of 0.''9 from the host nucleus (4.8 kpc projected distance at z = 0.3568), allow us to extract a relatively clean spectrum dominated by afterglow light. Furthermore, the spatially resolved spectrum allows us to constrain the properties of the explosion site directly, and compare these with the host galaxy nucleus, as well as other short-duration GRB host galaxies. We find that while the host is a relatively luminous (L∼0.8 L{sup *}{sub B}), star-forming (SFR = 1.84 M{sub ☉} yr{sup –1}) galaxy with almost solar metallicity, the spectrum of the afterglow exhibits weak Ca II absorption features but negligible emission features. The explosion site therefore lacks evidence of recent star formation, consistent with the relatively long delay time distribution expected in a compact binary merger scenario. The star formation rate (SFR; both in an absolute sense and normalized to the luminosity) and metallicity of the host are both consistent with the known sample of short-duration GRB hosts and with recent results which suggest GRB 130603B emission to be the product of the decay of radioactive species produced during the merging process of a neutron-star-neutron-star binary ({sup k}ilonova{sup )}. Ultimately, the discovery of more events similar to GRB 130603B and their rapid follow-up from 8 m class telescopes will open new opportunities for our understanding of the final stages of compact-objects binary systems and provide crucial 11. GOODS-Herschel: The far-infrared view of star formation in AGN host galaxies since z~3 Mullaney, J R; Daddi, E; Alexander, D M; Elbaz, D; Hickox, R C; Bournaud, F; Altieri, B; Aussel, H; Coia, D; Dannerbauer, H; Dasyra, K; Dickinson, M; Hwang, H S; Kartaltepe, J; Leiton, R; Magdis, G; Magnelli, B; Popesso, P; Valtchanov, I; Del Moro, A; Hanish, D J; Ivison, R J; Juneau, S; Lutz, D; Sargent, M T 2011-01-01 Using 100um and 160um fluxes from GOODS-Herschel - the deepest survey undertaken by the Herschel telescope - we explore the infrared properties of X-ray AGNs up to z~3. The observed 100um and 160um fluxes are dominated by the host galaxy in the vast majority of cases (>94 per cent), meaning that these far-infrared fluxes provide an uncontaminated view of the star formation in the host galaxies. There is no evidence of any correlation between the levels of AGN and global star formation activity at all surveyed redshifts. We confirm that the star formation rates of AGN hosts increase strongly with redshift; by a factor of 43^{+27}_{-18} from z50 per cent at Mstars>10^{11}Msun. We argue that our findings imply that the majority of moderate nuclear activity is fuelled by internal mechanisms rather than violent mergers, which suggests that high redshift disk instabilities could be an important AGN feeding mechanism. Our results also show it is stellar mass that is most important in dictating whether a galaxy hosts... 12. THE HOST GALAXY OF THE SUPER-LUMINOUS SN 2010gx AND LIMITS ON EXPLOSIVE {sup 56}Ni PRODUCTION Chen, Ting-Wan; Smartt, Stephen J.; Kotak, Rubina; McCrum, Matt; Fraser, Morgan [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Bresolin, Fabio; Kudritzki, Rolf-Peter [Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Pastorello, Andrea [INAF-Osservatorio Astronomico di Padova, vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Valenti, Stefano [Las Cumbres Observatory Global Telescope Network, Inc., Santa Barbara, CA 93117 (United States) 2013-02-01 Super-luminous supernovae have a tendency to occur in faint host galaxies which are likely to have low mass and low metallicity. While these extremely luminous explosions have been observed from z = 0.1 to 1.55, the closest explosions allow more detailed investigations of their host galaxies. We present a detailed analysis of the host galaxy of SN 2010gx (z = 0.23), one of the best studied super-luminous type Ic supernovae. The host is a dwarf galaxy (M{sub g} = -17.42 {+-} 0.17) with a high specific star formation rate. It has a remarkably low metallicity of 12 + log (O/H) = 7.5 {+-} 0.1 dex as determined from the detection of the [O III] {lambda}4363 line. This is the first reliable metallicity determination of a super-luminous stripped-envelope supernova host. We collected deep multi-epoch imaging with Gemini + GMOS between 240 and 560 days after explosion to search for any sign of radioactive {sup 56}Ni, which might provide further insights on the explosion mechanism and the progenitor's nature. We reach griz magnitudes of m{sub AB} {approx} 26, but do not detect SN 2010gx at these epochs. The limit implies that any {sup 56}Ni production was similar to or below that of SN 1998bw (a luminous type Ic SN that produced around 0.4 M{sub Sun} of {sup 56}Ni). The low volumetric rates of these supernovae ({approx}10{sup -4} of the core-collapse population) could be qualitatively matched if the explosion mechanism requires a combination of low-metallicity (below 0.2 Z{sub Sun }), high progenitor mass (>60 M{sub Sun }) and high rotation rate (fastest 10% of rotators). 13. The Contribution of Host Galaxies to the Infrared Energy Output of z ≳ 5.0 Quasars Lyu, Jianwei; Rieke, G. H.; Alberts, Stacey 2016-01-01 The infrared spectral energy distributions of z ≳ 5 quasars can be reproduced by combining a low-metallicity galaxy template with a standard active galactic nucleus (AGN) template. The host galaxy is represented by Haro 11, a compact, moderately low metallicity, starbursting galaxy that shares typical features of high-z galaxies. For the vast majority of z ≳ 5 quasars, the AGN contribution is well modeled by a standard empirical template with the contamination of star formation in the infrared subtracted. Together, these two templates can separate the contributions from the host galaxy and the AGN even in the case of limited data points, given that this model has only two free parameters. Using this method, we reanalyze 69 z ≳ 5 quasars with extensive Herschel observations and derive their AGN luminosities [LAGN = (0.78{--}27.4)× {10}13 {L}⊙ ], infrared luminosities from star formation [{L}{{SF,IR}}\\quad ≲ (1.5{--}25.7)× {10}12 {L}⊙ ], and corresponding star formation rates ({{SFR}}\\quad ≲ 290{--}2650{M}⊙ {{{yr}}}-1). The average infrared luminosity from star formation and the average total AGN luminosity of the z ≳ 5 quasar sample follow the correlation defined by quasars at z ˜ (3{--}5)× {10}11{M}⊙ . Combining with the black hole (BH) mass measurements, this stellar mass is adequate to establish a BH-galaxy mass ratio {M}{{BH}}/{M}* at 0.1%-1%, consistent with the local relation. 14. The effects of host galaxy properties on merging compact binaries detectable by LIGO O'Shaughnessy, Richard; Brooks, Alyson; Shen, Sijing; Governato, Fabio; Christensen, Charlotte 2016-01-01 Cosmological simulations of galaxy formation can produce present-day galaxies with a large range of assembly and star formation histories. A detailed study of the metallicity evolution and star formation history of such simulations can assist in predicting LIGO-detectable compact object binary mergers. Recent simulations of compact binary evolution suggest the compact object merger rate depends sensitively on the progenitor's metallicity. Rare low-metallicity star formation during galaxy assembly can produce more detected compact binaries than typical star formation. Using detailed simulations of galaxy and chemical evolution, we determine how sensitively the compact binary populations of galaxies with similar present-day appearance depend on the details of their assembly. We also demonstrate by concrete example the extent to which dwarf galaxies overabundantly produce compact binary mergers, particularly binary black holes, relative to more massive galaxies. We discuss the implications for transient multimes... 15. The effects of host galaxy properties on merging compact binaries detectable by LIGO O'Shaughnessy, R.; Bellovary, J. M.; Brooks, A.; Shen, S.; Governato, F.; Christensen, C. R. 2017-01-01 Cosmological simulations of galaxy formation can produce present-day galaxies with a large range of assembly and star formation histories. A detailed study of the metallicity evolution and star formation history of such simulations can assist in predicting Laser Interferometer Gravitational-Wave Observatory (LIGO)-detectable compact object binary mergers. Recent simulations of compact binary evolution suggest that the compact object merger rate depends sensitively on the progenitor's metallicity. Rare low-metallicity star formation during galaxy assembly can produce more detected compact binaries than typical star formation. Using detailed simulations of galaxy and chemical evolution, we determine how sensitively the compact binary populations of galaxies with a similar present-day appearance depend on the details of their assembly. We also demonstrate by concrete example the extent to which dwarf galaxies overabundantly produce compact binary mergers, particularly binary black holes, relative to more massive galaxies. We discuss the implications for transient multimessenger astronomy with compact binary sources. 16. The evolution of superluminous supernova LSQ14mo and its interacting host galaxy system Chen, T -W; Smartt, S J; Mazzali, P A; Yates, R M; Moriya, T J; Inserra, C; Langer, N; Kruehler, T; Pan, Y -C; Kotak, R; Galbany, L; Schady, P; Wiseman, P; Greiner, J; Schulze, S; Man, A W S; Jerkstrand, A; Smith, K W; Dennefeld, M; Baltay, C; Bolmer, J; Kankare, E; Knust, F; Maguire, K; Rabinowitz, D; Rostami, S; Sullivan, M; Young, D R 2016-01-01 We present and analyse an extensive dataset of the superluminous supernova LSQ14mo (z = 0.256), consisting of a multi-colour lightcurve from -30 d to +70 d in the rest-frame and a series of 6 spectra from PESSTO covering -7 d to +50 d. This is among the densest spectroscopic coverage, and best-constrained rising lightcurve, for a fast-declining hydrogen-poor superluminous supernova. The bolometric lightcurve can be reproduced with a millisecond magnetar model with ~ 4 M_sol ejecta mass, and the temperature and velocity evolution is also suggestive of a magnetar as the power source. Spectral modelling indicates that the SN ejected ~ 6 M_sol of CO-rich material with a kinetic energy of ~ 7 x 10^51 erg, and suggests a partially thermalised additional source of luminosity between -2 d and +22 d. This may be due to interaction with a shell of material originating from pre-explosion mass loss. We further present a detailed analysis of the host galaxy system of LSQ14mo. PESSTO and GROND imaging show three spatially ... 17. High-redshift quasars host galaxies: is there a stellar mass crisis? Valiante, Rosa; Salvadori, Stefania; Gallerani, Simona 2014-01-01 We investigate the evolutionary properties of a sample of quasars at 5hosts have final stellar masses in the range$(4-6)\\times 10^{11} M_{sun}$, a factor 3-30 larger than the upper limits allowed by the observations. We discuss alternative scenarios to alleviate this apparent tension: the most likely explanation resides in the large uncertainties that still affect dynamical mass measurements in these high-z galaxies. In addition, during the transition between the starburs... 18. The Host Galaxies of X-ray Quasars Are Not Strong Star Formers Barger, A J; Owen, F N; Chen, C -C; Hasinger, G; Hsu, L -Y; Li, Y 2014-01-01 We use ultradeep SCUBA-2 850um observations (~0.37 mJy rms) of the 2 Ms CDF-N and 4 Ms CDF-S X-ray fields to examine the amount of dusty star formation taking place in the host galaxies of high-redshift X-ray AGNs. Supplementing with COSMOS, we measure the submillimeter fluxes of the 4-8 keV sources at z>1, finding little flux at the highest X-ray luminosities but significant flux at intermediate luminosities. We determine grey body and MIR luminosities by fitting spectral energy distributions to each X-ray source and to each radio source in an ultradeep Karl G. Jansky VLA 1.4 GHz (11.5uJy at 5-sigma) image of the CDF-N. We confirm the FIR-radio and MIR-radio correlations to z=4 using the non-X-ray detected radio sources. Both correlations are also obeyed by the X-ray less luminous AGNs but not by the X-ray quasars. We interpret the low FIR luminosities relative to the MIR for the X-ray quasars as being due to a lack of star formation, while the MIR stays high due to the AGN contribution. We find that the FIR... 19. SNe Ia host galaxy properties from Sloan Digital Sky Survey-II spectroscopy Johansson, Jonas; Pforr, Janine; Maraston, Claudia; Nichol, Robert C; Smith, Mathew; Lampeitl, Hubert; Beifiori, Alessandra; Gupta, Ravi R; Schneider, Donald P 2012-01-01 We study the stellar populations of SNe Ia host galaxies using SDSS-II spectroscopy. We focus on the relationships of SNe Ia properties with stellar velocity dispersion and the stellar population parameters age, metallicity and element abundance ratios derived by fitting absorption line indices to stellar population models. We concentrate on a sub-sample of 84 SNe Ia from the SDSS-II Supernova Survey. In agreement with previous findings, we find that SALT2 stretch factor values show the strongest dependence on stellar population age. Hence, SNe Ia peak-luminosity is closely related to the age of the stellar progenitor systems, where more luminous SNe Ia appear in younger stellar populations. We find no statistically significant trends in the Hubble residual with any of the stellar population parameters studied, including age and metallicity contrary to the literature, as well as with stellar velocity dispersion. Moreover, we find that the method of stellar mass derivation is affecting the Hubble residual-mass... 20. The disc-dominated host galaxy of FR-I radio source B2 0722+30 Emonts, B H C; Morganti, R; Oosterloo, T A; Holt, J; Brogt, E; Van Moorsel, G 2009-01-01 We present new observational results that conclude that the nearby radio galaxy B2 0722+30 is one of the very few known disc galaxies in the low-redshift Universe that host a classical double-lobed radio source. In this paper we use HI observations, deep optical imaging, stellar population synthesis modelling and emission-line diagnostics to study the host galaxy, classify the Active Galactic Nucleus and investigate environmental properties under which a radio-loud AGN can occur in this system. Typical for spiral galaxies, B2 0722+30 has a regularly rotating gaseous disc throughout which star formation occurs. Dust heating by the ongoing star formation is likely responsible for the high infrared luminosity of the system. The optical emission-line properties of the central region identify a Low Ionization Nuclear Emission-line Region (LINER)-type nucleus with a relatively low [OIII] luminosity, in particular when compared with the total power of the Fanaroff & Riley type-I radio source that is present in t... 1. WISE colours and star-formation in the host galaxies of radio-loud narrow-line Seyfert 1 Caccianiga, A; Ballo, L; Foschini, L; Maccacaro, T; Della Ceca, R; Severgnini, P; Marcha, M J; Mateos, S; Sani, E 2015-01-01 We investigate the mid-infrared properties of the largest (42 objects) sample of radio-loud narrow-line Seyfert 1 (RL NLS1) collected to date, using data from the Wide-field Infrared Survey Explorer (WISE). We analyse the mid-IR colours of these objects and compare them to what is expected from different combinations of AGN and galaxy templates. We find that, in general, the host-galaxy emission gives an importan contribution to the observed mid-IR flux in particular at the longest wavelengths (W3, at 12micron, and W4, at 22micron). In about half of the sources (22 objects) we observe a very red mid-IR colour (W4-W3>2.5) that can be explained only using a starburst galaxy template (M82). Using the 22micron luminosities, corrected for the AGN contribution, we have then estimated the star-formation rate for 20 of these "red" RL NLS1, finding values ranging from 10 to 500 Msun/y. For the RL NLS1 showing bluer colours, instead, we cannot exclude the presence of a star-forming host galaxy although, on average, we ... 2. Determining the nature of orbits in a three-dimensional galaxy model hosting a BL Lacertae object Zotos, Euaggelos E 2014-01-01 A three-dimensional dynamical model for a galaxy hosting a BL Lacertae object is constructed. The model consists of a logarithmic potential representing an elliptical host galaxy with a bulge of radius$c_b$and a dense massive nucleus. Using numerical experiments, we try to distinguish between regular and chaotic motion in both 2D and 3D system. In particular, we investigate how the basic parameters of our model, such as the mass of the nucleus, the internal perturbation and the flattening parameters influence the amount and the degree of chaos. Interesting correlations are presented for both 2D and 3D dynamical models. Our numerical results are explained and supported using elementary theoretical arguments and analytical calculations. Of particular interest, is the local integral of motion which have been found to exist in the vicinity of stable periodic points. The obtained numerical outcomes of the present research, are linked and also compared with several data derived from observations. 3. SDSS-II Supernova Survey: An Analysis of the Largest Sample of Type Ia Supernovae and Correlations with Host-Galaxy Spectral Properties Wolf, Rachel C; Gupta, Ravi R; Sako, Masao; Fischer, John A; Kessler, Rick; Jha, Saurabh W; March, Marisa C; Scolnic, Daniel M; Fischer, Johanna-Laina; Campbell, Heather; Nichol, Robert C; Olmstead, Matthew D; Richmond, Michael; Schneider, Donald P; Smith, Mathew 2016-01-01 Using the largest single-survey sample of Type Ia supernovae (SNe Ia) to date, we study the relationship between properties of SNe Ia and those of their host galaxies, focusing primarily on correlations with Hubble residuals (HR). Our sample consists of 345 photometrically-classified or spectroscopically-confirmed SNeIa discovered as part of the SDSS-II Supernova Survey (SDSS-SNS). This analysis utilizes host-galaxy spectroscopy obtained during the SDSS-I/II spectroscopic survey and from an ancillary program on the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) that obtained spectra for nearly all host galaxies of SDSS-II SN candidates. In addition, we use photometric host-galaxy properties from the SDSS-SNS data release (Sako et al. 2014) such as host stellar mass and star-formation rate. We confirm the well-known relation between HR and host-galaxy mass and find a 3.6{\\sigma} significance of a non-zero linear slope. We also recover correlations between HR and host-galaxy gas-phase metallicity and s... 4. A population of massive, luminous galaxies hosting heavily dust-obscured gamma-ray bursts: Implications for the use of GRBs as tracers of cosmic star formation Perley, D. A. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Blvd., Pasadena, CA 91125 (United States); Levan, A. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Cenko, S. B.; Bloom, J. S.; Filippenko, A. V.; Morgan, A. N. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Hjorth, J.; Krühler, T.; Fynbo, J. P. U.; Milvang-Jensen, B. [Dark Cosmology Centre, Niels Bohr Institute, Copenhagen (Denmark); Fruchter, A.; Kalirai, J. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavík (Iceland); Prochaska, J. X. [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Silverman, J. M., E-mail: [email protected] [Department of Astronomy, University of Texas, Austin, TX 78712 (United States) 2013-12-01 We present observations and analysis of the host galaxies of 23 heavily dust-obscured gamma-ray bursts (GRBs) observed by the Swift satellite during the years 2005-2009, representing all GRBs with an unambiguous host-frame extinction of A{sub V} > 1 mag from this period. Deep observations with Keck, Gemini, Very Large Telescope, Hubble Space Telescope, and Spitzer successfully detect the host galaxies and establish spectroscopic or photometric redshifts for all 23 events, enabling us to provide measurements of the intrinsic host star formation rates, stellar masses, and mean extinctions. Compared to the hosts of unobscured GRBs at similar redshifts, we find that the hosts of dust-obscured GRBs are (on average) more massive by about an order of magnitude and also more rapidly star forming and dust obscured. While this demonstrates that GRBs populate all types of star-forming galaxies, including the most massive, luminous systems at z ≈ 2, at redshifts below 1.5 the overall GRB population continues to show a highly significant aversion to massive galaxies and a preference for low-mass systems relative to what would be expected given a purely star-formation-rate-selected galaxy sample. This supports the notion that the GRB rate is strongly dependent on metallicity, and may suggest that the most massive galaxies in the universe underwent a transition in their chemical properties ∼9 Gyr ago. We also conclude that, based on the absence of unobscured GRBs in massive galaxies and the absence of obscured GRBs in low-mass galaxies, the dust distributions of the lowest-mass and the highest-mass galaxies are relatively homogeneous, while intermediate-mass galaxies (∼10{sup 9} M {sub ☉}) have diverse internal properties. 5. AGN Feedback, Host Halo Mass and Central Cooling Time: Implications for Galaxy Formation Efficiency and$M_{BH} - \\sigma$Main, Robert; Nulsen, Paul; Russell, Helen; Vantyghem, Adrian 2015-01-01 We derive X-ray mass, luminosity, and temperature profiles for 45 galaxy clusters to explore relationships between halo mass, AGN feedback, and central cooling time. We find that radio--mechanical feedback power (referred to here as "AGN power") in central cluster galaxies correlates with halo mass, but only in halos with central atmospheric cooling times shorter than 1 Gyr. This timescale corresponds approximately to the cooling time (entropy) threshold for the onset of cooling instabilities and star formation in central galaxies (Rafferty et al. 2008). No correlation is found in systems with central cooling times greater than 1 Gyr. The trend with halo mass is consistent with self-similar scaling relations assuming cooling is regulated by feedback. The trend is also consistent with galaxy and central black hole co-evolution along the$M_{BH} - \\sigma relation. AGN power further correlates with X-ray gas mass and the host galaxy's K-band luminosity. AGN power in clusters with central atmospheric cooling ti... 6. Blending bias impacts the host halo masses derived from a cross-correlation analysis of bright sub-millimetre galaxies Cowley, William I; Baugh, Carlton M; Cole, Shaun; Wilkinson, Aaron 2016-01-01 Placing bright sub-millimetre galaxies (SMGs) within the broader context of galaxy formation and evolution requires accurate measurements of their clustering, which can constrain the masses of their host dark matter halos. Recent work has shown that the clustering measurements of these galaxies may be affected by a blending bias,' which results in the angular correlation function of the sources extracted from single-dish imaging surveys being boosted relative to that of the underlying galaxies. This is due to confusion introduced by the coarse angular resolution of the single-dish telescope and could lead to the inferred halo masses being significantly overestimated. We investigate the extent to which this bias affects the measurement of the correlation function of SMGs when it is derived via a cross-correlation with a more abundant galaxy population. We find that the blending bias is essentially the same as in the auto-correlation case and conclude that the best way to reduce its effects is to calculate the... 7. Optical Identification of Cepheids in 19 Host Galaxies of Type Ia Supernovae and NGC 4258 with the Hubble Space Telescope Hoffmann, Samantha L; Riess, Adam G; Yuan, Wenlong; Casertano, Stefano; Filippenko, Alexei V; Tucker, Brad E; Chornock, Ryan; Silverman, Jeffrey M; Welch, Douglas L; Goobar, Ariel; Amanullah, Rahman 2016-01-01 We present results of an optical search for Cepheid variable stars using the Hubble Space Telescope (HST) in 19 hosts of Type Ia supernovae (SNe Ia) and the maser-host galaxy NGC 4258, conducted as part of the SH0ES project (Supernovae and H0 for the Equation of State of dark energy). The targets include 9 newly imaged SN Ia hosts using a novel strategy based on a long-pass filter that minimizes the number of HST orbits required to detect and accurately determine Cepheid properties. We carried out a homogeneous reduction and analysis of all observations, including new universal variability searches in all SN Ia hosts, that yielded a total of 2200 variables with well-defined selection criteria -- the largest such sample identified outside the Local Group. These objects are used in a companion paper to determine the local value of H0 with a total uncertainty of 2.4%. 8. AGN-host connection at 0.5 < z < 2.5: A rapid evolution of AGN fraction in red galaxies during the last 10 Gyr Wang, Tao; Elbaz, D.; Alexander, D. M.; Xue, Y. Q.; Gabor, J. M.; Juneau, S.; Schreiber, C.; Zheng, X.-Z.; Wuyts, S.; Shi, Y.; Daddi, E.; Shu, X.-W.; Fang, G.-W.; Huang, J.-S.; Luo, B.; Gu, Q.-S. 2017-05-01 We explore the dependence of the incidence of moderate-luminosity (L0.5-8 keV = 1041.9-43.7 erg s-1) active galactic nuclei (AGNs) and the distribution of their accretion rates on host color at 0.5 1010 M⊙. We use extinction-corrected rest-frame U-V colors to divide both AGN hosts and non-AGN galaxies into red sequence (red), green valley (green), and blue cloud (blue) populations. We find that the fraction of galaxies hosting an AGN at fixed X-ray luminosity increases with stellar mass and redshift for all the three galaxy populations, independent of their colors. However, both the AGN fraction at fixed stellar mass and its evolution with redshift are clearly dependent on host colors. Most notably, red galaxies have the lowest AGN fraction ( 5%) at z 1 yet with most rapid evolution with redshift, increasing by a factor of 5 (24%) at z 2. Green galaxies exhibit the highest AGN fraction across all redshifts, which is most pronounced at z 2 with more than half of them hosting an AGN at M∗ > 1010.6 M⊙. Together with the high AGN fraction in red galaxies at z 2, this indicates that (X-ray) AGNs could be important in both transforming (quenching) star-forming galaxies into quiescent ones and subsequently maintaining their quiescence at high redshift. Furthermore, consistent with previous studies at lower redshifts, we show that the probability of hosting an AGN for the total galaxy population can be characterized by a universal Eddington ratio (as approximated by LX/M∗) distribution (p(λEdd) λEdd-0.4), which is independent on host mass. Yet consistent with their different AGN fractions, galaxies with different colors appear to also have different p(λEdd) with red galaxies exhibiting more rapid redshift evolution compared with that for green and blue galaxies. Evidence for a steeper power-law distribution of p(λEdd) in red galaxies (p(λEdd) λEdd-0.6) is also presented, though larger samples are needed to confirm. These results suggest that the AGN accretion 9. Star Cluster Complexes and the Host Galaxy in Three HII Galaxies: Mrk 36, UM 408, and UM 461 Lagos, Patricio; Nigoche-Netro, A; Carrasco, Eleazar Rodrigo 2011-01-01 We present a stellar population study of three HII galaxies (Mrk 36, UM 408, and UM 461) based on the analysis of new ground-based high resolution near-infrared J, H and Kp broad-band and Br narrow-band images obtained with Gemini/NIRI. We identify and determine relative ages and masses of the elementary star clusters and/or star cluster complexes of the starburst regions in each of these galaxies by comparing the colors with evolutionary synthesis models that include the contribution of stellar continuum, nebular continuum and emission lines. We found that the current star cluster formation efficiency in our sample of low luminosity HII galaxies is ~10%. Therefore, most of the recent star formation is not in massive clusters. Our findings seem to indicate that the star formation mode in our sample of galaxies is clumpy, and that these complexes are formed by a few massive star clusters with masses > 10^4 Mo. The age distribution of these star cluster complexes shows that the current burst started recently an... 10. The Afterglow and Early-Type Host Galaxy of the Short GRB 150101B at z=0.1343 Fong, Wen-fai; Chornock, Ryan; Berger, Edo; Shappee, Benjamin J; Levan, Andrew J; Tanvir, Nial R; Smith, Nathan; Milne, Peter A; Laskar, Tanmoy; Fox, Derek B; Lunnan, Ragnhild; Blanchard, Peter K; Hjorth, Jens; Wiersema, Klaas; van der Horst, Alexander J; Zaritsky, Dennis 2016-01-01 We present the discovery of the X-ray and optical afterglows of the short-duration GRB 150101B, pinpointing the event to an early-type host galaxy at z=0.1343 +/- 0.0030. This makes GRB 150101B the most nearby short GRB with an early-type host galaxy discovered to date. Fitting the spectral energy distribution of the host galaxy results in an inferred stellar mass of ~7x10^10 M_sol, stellar population age of ~2-2.5 Gyr, and star formation rate of 9 deg. Using observations extending to ~30 days, we place upper limits of <(2-4)x10^41 erg s^-1 on associated kilonova emission. We compare searches following previous short GRBs to existing kilonova models, and demonstrate the difficulty of performing effective kilonova searches from cosmological short GRBs using current ground-based facilities. We show that at the Advanced LIGO/VIRGO horizon distance of 200 Mpc, searches reaching depths of ~23-24 AB mag are necessary to probe a meaningful range of kilonova models. 11. The Type Ia Supernova Color-Magnitude Relation and Host Galaxy Dust: A Simple Hierarchical Bayesian Model Mandel, Kaisey S; Shariff, Hikmatali; Foley, Ryan J; Kirshner, Robert P 2016-01-01 Conventional Type Ia supernova (SN Ia) cosmology analyses currently use a simplistic linear regression of magnitude versus color and light curve shape, which does not model intrinsic SN Ia variations and host galaxy dust as physically distinct effects, resulting in low color-magnitude slopes. We construct a probabilistic generative model for the distribution of dusty extinguished absolute magnitudes and apparent colors as a convolution of the intrinsic SN Ia color-magnitude distribution and the host galaxy dust reddening-extinction distribution. If the intrinsic color-magnitude (M_B vs. B-V) slope beta_int differs from the host galaxy dust law R_B, this convolution results in a specific curve of mean extinguished absolute magnitude vs. apparent color. The derivative of this curve smoothly transitions from beta_int in the blue tail to R_B in the red tail of the apparent color distribution. The conventional linear fit approximates this effective curve at this transition near the average apparent color, resultin... 12. A Revised Host Galaxy Association for GRB 020819B: A High-Redshift Dusty Starburst, Not a Low-Redshift Gas-Poor Spiral Perley, Daniel A; Schady, Patricia; Michałowski, Michał J; Thöne, Christina C; Petry, Dirk; Graham, John F; Greiner, Jochen; Schulze, Steve; Kim, Sam 2016-01-01 The purported spiral host galaxy of GRB 020819B at z=0.41 has been seminal in establishing our view of the diversity of long-duration gamma-ray burst environments: optical spectroscopy of this host provided evidence that GRBs can form even at high metallicities, while millimetric observations suggested that GRBs may preferentially form in regions with minimal molecular gas. We report new observations from VLT (MUSE and X-shooter) which demonstrate that the purported host is an unrelated foreground galaxy. The probable radio afterglow is coincident with a compact, highly star-forming, dusty galaxy at z=1.9621. The revised redshift naturally explains the apparent nondetection of CO(3-2) line emission at the afterglow site from ALMA. There is no evidence that molecular gas properties in GRB host galaxies are unusual, and limited evidence that GRBs can form readily at super-Solar metallicity. 13. Galaxies in COSMOS: Evolution of Black hole vs. bulge mass but not vs. total stellar mass over the last 9 Gyrs? Jahnke, Knud; Brusa, Marcella; Capak, Peter; Cappelluti, Nico; Cisternas, Mauricio; Civano, Francesca; Colbert, James; Comastri, Andrea; Elvis, Martin; Hasinger, Günther; Impey, Chris; Inskip, Katherine; Koekemoer, Anton M; Lilly, Simon; Maier, Christian; Merloni, Andrea; Riechers, Dominik; Salvato, Mara; Schinnerer, Eva; Scoville, Nick Z; Silverman, John; Taniguchi, Yoshi; Trump, Jonathan R; Yan, Lin 2009-01-01 We constrain the ratio of black hole (BH) mass to total stellar mass of type-1 AGN in the COSMOS survey at 1host galaxy colors which constrain mass-to-light ratios. All objects have virial BH mass-estimates available from the COSMOS Magellan/IMACS and zCOSMOS surveys. We find zero difference between the M_BH--M_(*,total)-relation at z~1.4 and the M_BH--M_(*,bulge)-relation in the local Universe. Our interpretation is: (a) If our objects were purely bulge-dominated, the M_BH--M_(*,bulge)-relation has not evolved since z~1.4. However, (b) since we have evidence for substantial disk components, the bulges of massive galaxies (logM_(*,total)=11.1+-0.25 or logM_BH~8.3+-0.2) must have grown over the last 9 Gyrs predominantly by redistribution of disk- into bulge-mass. Since all necessary stellar mass exists in the galaxy at z=1.4, no star... 14. Obscured Supermassive Black Hole Growth - Connections to Host Galaxies and Evolutionary Models DiPompeo, Michael A.; Hickox, Ryan C.; Myers, Adam D. 2017-08-01 A large fraction of the supermassive black hole growth in the Universe is hidden from view behind thick columns of dust. The most heavily obscured quasars can be challenging to detect even with current high energy X-ray observatories such as NuSTAR - however with infrared observations that can detect the hot nuclear dust in even the most enshrouded systems, we are now beginning to characterize large populations of these hidden monsters.With roughly half-a-million quasars selected with WISE, we have found via clustering and CMB lensing cross-correlation measurements that obscured quasars reside in dark matter halos 0.5 dex more massive than unobscured quasars. This implies that obscuration is directly linked to host galaxy properties, and not simply the dust geometry around the quasar. Using cross-correlations we accurately characterize the redshift distribution of the obscured quasar population, confirming that it peaks at z = 1, and using long-wavelength bands find that it has a similar bolometric luminosity distribution as unobscured quasars as well. Finally, using a simple model based on empirical relationships between halo, stellar, and black hole masses, we show that an evolutionary sequence from obscured to unobscured quasar, combined with a flux limit, can predict the observed halo mass differences.Studies of the most obscured quasars provide valuable insights on the rapid growth of the most massive black holes in the Universe, and motivates future work with the next generation high energy observatories such as eROSITA, Athena, and Lynx. 15. Properties of compact HII regions and their host clumps in the inner vs outer Galaxy - early results from SASSy Djordjevic, Julie; Thompson, Mark; Urquhart, James S. 2017-01-01 We present a catalog of compact and ultracompact HII regions for all Galactocentric radii. Previous catalogs focus on the inner Galaxy (Rgal ≤ 8 kpc) but the recent SASSy 870 µm survey allows us to identify regions out to ~20 kpc. Early samples are also filled with false classifications leading to uncertainty when deriving star formation efficiencies in Galactic models. These objects have similar mid-IR colours to HII regions. Urquhart et al. (2013) found that they could use mid-IR, submm, and radio data to identify the genuine compact HII regions, avoiding confusion. They used this method on a small portion of the Galaxy (10 < l < 60), identifying 213 HII regions embedded in 170 clumps. We use ATLASGAL and SASSy, crossmatched with RMS, to sample the remaining galactic longitudes out to Rgal = 20 kpc. We derive the properties of the identified compact HII regions and their host clumps while addressing the implications for recent massive star formation in the outer Galaxy. Observations towards nearby galaxies are biased towards massive stars, affecting simulations and overestimating models for galactic evolution and star formation rates. The Milky Way provides the ideal template for studying factors affecting massive star formation rates and efficiencies at high resolution, thus fine-tuning those models. We find that there is no significant change in the rate of massive star formation in the outer vs inner Galaxy. Despite some peaks in known complexes and possible correlation with spiral arms, the outer Galaxy appears to produce massive stars as efficiently as the inner regions. However, many of the potential star forming SASSy clumps have no available radio counterpart to confirm the presence of an HII region or other star formation tracer. Follow-up observations will be required to verify this conclusion and are currently in progress. 16. The Type Ia Supernova Color-Magnitude Relation and Host Galaxy Dust: A Simple Hierarchical Bayesian Model Mandel, Kaisey S.; Scolnic, Daniel M.; Shariff, Hikmatali; Foley, Ryan J.; Kirshner, Robert P. 2017-06-01 Conventional Type Ia supernova (SN Ia) cosmology analyses currently use a simplistic linear regression of magnitude versus color and light curve shape, which does not model intrinsic SN Ia variations and host galaxy dust as physically distinct effects, resulting in low color-magnitude slopes. We construct a probabilistic generative model for the dusty distribution of extinguished absolute magnitudes and apparent colors as the convolution of an intrinsic SN Ia color-magnitude distribution and a host galaxy dust reddening-extinction distribution. If the intrinsic color-magnitude (M B versus B - V) slope {β }{int} differs from the host galaxy dust law R B , this convolution results in a specific curve of mean extinguished absolute magnitude versus apparent color. The derivative of this curve smoothly transitions from {β }{int} in the blue tail to R B in the red tail of the apparent color distribution. The conventional linear fit approximates this effective curve near the average apparent color, resulting in an apparent slope {β }{app} between {β }{int} and R B . We incorporate these effects into a hierarchical Bayesian statistical model for SN Ia light curve measurements, and analyze a data set of SALT2 optical light curve fits of 248 nearby SNe Ia at zlinear fit gives {β }{app}≈ 3. Our model finds {β }{int}=2.3+/- 0.3 and a distinct dust law of {R}B=3.8+/- 0.3, consistent with the average for Milky Way dust, while correcting a systematic distance bias of ˜0.10 mag in the tails of the apparent color distribution. Finally, we extend our model to examine the SN Ia luminosity-host mass dependence in terms of intrinsic and dust components. 17. Origin of X-shaped radio-sources: further insights from the properties of their host galaxies Gillone, Melissa; Rossi, Paola 2015-01-01 We analyze the properties of a sample of X-shaped radio-sources (XRSs). These objects show, in addition to the main lobes, a pair of wings producing their peculiar radio morphology. We obtain our sample by selecting from the initial list of Cheung (2007, AJ, 133, 2097) the 53 galaxies with the better defined wings and with available SDSS images. We identified the host galaxies and measured their optical position angle, obtaining a positive result in 22 cases. The orientation of the secondary radio structures shows a strong connection with the optical axis, with all (but one) wing forming a angle larger than 40 degrees with the host major axis. The probability that this is compatible with a uniform distribution is P = 0.9 10E-4. Spectra are available from the SDSS for 28 XRSs. We modeled them to extract information on their emission lines and stellar population properties. The sample is formed by approximately the same number of high and low excitation galaxies (HEG and LEG); this classification is essential f... 18. On the origin of X-shaped radio-sources new insights from the properties of their host galaxies Capetti, A; Rossi, P; Bodo, G; Zanni, C; Massaglia, S 2002-01-01 A significant fraction of extended radio sources presents a peculiar X-shaped radio morphology: in addition to the classical double lobed structure, radio emission is also observed along a second axis of symmetry in the form of diffuse wings or tails. We re-examine the origin of these extensions relating the radio morphology to the properties of their host galaxies. The orientation of the wings shows a striking connection with the structure of the host galaxy as they are preferentially aligned with its minor axis. Furthermore, wings are only observed in galaxies of high projected ellipticity. Hydrodynamical simulations of the radio-source evolution show that X-shaped radio-sources naturally form in this geometrical situation: as a jet propagates in a non-spherical gas distribution, the cocoon surrounding the radio-jets expands laterally at a high rate producing wings of radio emission, in a way that is reminiscent of the twin-exhaust model for radio-sources. 19. The Swift GRB Host Galaxy Legacy Survey. II. Rest-frame Near-IR Luminosity Distribution and Evidence for a Near-solar Metallicity Threshold Perley, D. A.; Tanvir, N. R.; Hjorth, J.; Laskar, T.; Berger, E.; Chary, R.; de Ugarte Postigo, A.; Fynbo, J. P. U.; Krühler, T.; Levan, A. J.; Michałowski, M. J.; Schulze, S. 2016-01-01 We present rest-frame near-IR (NIR) luminosities and stellar masses for a large and uniformly selected population of gamma-ray burst (GRB) host galaxies using deep Spitzer Space Telescope imaging of 119 targets from the Swift GRB Host Galaxy Legacy Survey spanning 0.03 effects of galaxy evolution and chemical enrichment on the mass distribution of the GRB host population across cosmic history. We find a rapid increase in the characteristic NIR host luminosity between z ˜ 0.5 and z ˜ 1.5, but little variation between z ˜ 1.5 and z ˜ 5. Dust-obscured GRBs dominate the massive host population but are only rarely seen associated with low-mass hosts, indicating that massive star-forming galaxies are universally and (to some extent) homogeneously dusty at high redshift while low-mass star-forming galaxies retain little dust in their interstellar medium. Comparing our luminosity distributions with field surveys and measurements of the high-z mass-metallicity relation, our results have good consistency with a model in which the GRB rate per unit star formation is constant in galaxies with gas-phase metallicity below approximately the solar value but heavily suppressed in more metal-rich environments. This model also naturally explains the previously reported “excess” in the GRB rate beyond z ≳ 2 metals stifle GRB production in most galaxies at z < 1.5 but have only minor impact at higher redshifts. The metallicity threshold we infer is much higher than predicted by single-star models and favors a binary progenitor. Our observations also constrain the fraction of cosmic star formation in low-mass galaxies undetectable to Spitzer to be small at z < 4. 20. THE SWIFT GRB HOST GALAXY LEGACY SURVEY. II. REST-FRAME NEAR-IR LUMINOSITY DISTRIBUTION AND EVIDENCE FOR A NEAR-SOLAR METALLICITY THRESHOLD Perley, D. A. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Blvd., Pasadena, CA 91125 (United States); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom); Hjorth, J.; Fynbo, J. P. U.; Krühler, T. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 København Ø (Denmark); Laskar, T.; Berger, E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chary, R. [US Planck Data Center, MS220-6, Pasadena, CA 91125 (United States); Postigo, A. de Ugarte [Instituto de Astrofísica de Andalucía (IAA-CSIC), Glorieta de la Astronomía s/n, E-18008, Granada (Spain); Levan, A. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Michałowski, M. J. [Scottish Universities Physics Alliance, Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ (United Kingdom); Schulze, S., E-mail: [email protected] [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, 7820436 Macul, Santiago 22 (Chile) 2016-01-20 We present rest-frame near-IR (NIR) luminosities and stellar masses for a large and uniformly selected population of gamma-ray burst (GRB) host galaxies using deep Spitzer Space Telescope imaging of 119 targets from the Swift GRB Host Galaxy Legacy Survey spanning 0.03 < z < 6.3, and we determine the effects of galaxy evolution and chemical enrichment on the mass distribution of the GRB host population across cosmic history. We find a rapid increase in the characteristic NIR host luminosity between z ∼ 0.5 and z ∼ 1.5, but little variation between z ∼ 1.5 and z ∼ 5. Dust-obscured GRBs dominate the massive host population but are only rarely seen associated with low-mass hosts, indicating that massive star-forming galaxies are universally and (to some extent) homogeneously dusty at high redshift while low-mass star-forming galaxies retain little dust in their interstellar medium. Comparing our luminosity distributions with field surveys and measurements of the high-z mass–metallicity relation, our results have good consistency with a model in which the GRB rate per unit star formation is constant in galaxies with gas-phase metallicity below approximately the solar value but heavily suppressed in more metal-rich environments. This model also naturally explains the previously reported “excess” in the GRB rate beyond z ≳ 2; metals stifle GRB production in most galaxies at z < 1.5 but have only minor impact at higher redshifts. The metallicity threshold we infer is much higher than predicted by single-star models and favors a binary progenitor. Our observations also constrain the fraction of cosmic star formation in low-mass galaxies undetectable to Spitzer to be small at z < 4. 1. AGN-Enhanced Outflows of Low-Ionization Gas in Star-Forming Galaxies at 1.7 Talia, Margherita; Brusa, Marcella; Cimatti, Andrea; VUDS Team 2017-07-01 To reproduce the properties of galaxies in the local Universe, as well as the scaling relations between host galaxies and black holes properties, many galaxy formation models invoke the presence of fast and energetic winds extending over galaxy scales. These massive gas outflows can be powered either by star-formation (SF) or AGN activity, though the relative dominance and efficiency of the different mechanisms is not yet fully understood. In the last decade much effort has been put in the search for observational evidence of such phenomena, especially at the peak of both SF and AGN activity through cosmic time (1evidence of fast material moving towards our line of sight. More recently, especially thanks to new facilities like ALMA, outflows are being observed also in neutral and molecular gas. We collected a large sample of AGNs and SFGs at z>1 from large optical spectroscopic surveys (zCOSMOS, VUDS, ESO public surveys), complemented with HST imaging, X-ray (Chandra) and IR data, and we concentrated our analysis on the ISM absorption lines in the rest-frame UV wavelength range. The analysis of the ISM absorption lines in stacked spectra confirmed that galaxies hosting an AGN show outflows moving at speeds ( 600-800 km/s) much faster than in the case of pure SFGs. However, though the AGN might be responsible of an enhanced gas outflow activity with respect to SF alone, the analysis of the sample also shows that there is no correlation between the power of the AGN, as traced by its X-ray luminosity, and the velocity of the warm phase of the outflow traced by the ISM UV absorption lines. This result is at odds with previous findings reported for the highly ionized phase in local AGN, suggesting that the two phases of the outflow are mixed only in relatively low-velocity outflows. 2. SDSS-II Supernova survey. An analysis of the largest sample of type IA supernovae and correlations with host-galaxy spectral properties Wolf, Rachel C.; D’Andrea, Chris B.; Gupta, Ravi R.; Sako, Masao; Fischer, John A.; Kessler, Rick; Jha, Saurabh W.; March, Marisa C.; Scolnic, Daniel M.; Fischer, Johanna-Laina; Campbell, Heather; Nichol, Robert C.; Olmstead, Matthew D.; Richmond, Michael; Schneider, Donald P.; Smith, Mathew 2016-04-20 Using the largest single-survey sample of Type Ia supernovae (SNe Ia) to date, we study the relationship between properties of SNe Ia and those of their host galaxies, focusing primarily on correlations with Hubble residuals (HR). Our sample consists of 345 photometrically-classified or spectroscopicallyconfirmed SNe Ia discovered as part of the SDSS-II Supernova Survey (SDSS-SNS). This analysis utilizes host-galaxy spectroscopy obtained during the SDSS-I/II spectroscopic survey and from an ancillary program on the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) that obtained spectra for nearly all host galaxies of SDSS-II SN candidates. In addition, we use photometric hostgalaxy properties from the SDSS-SNS data release (Sako et al. 2014) such as host stellar mass and star-formation rate. We confirm the well-known relation between HR and host-galaxy mass and find a 3.6σ significance of a non-zero linear slope. We also recover correlations between HR and hostgalaxy gas-phase metallicity and specific star-formation rate as they are reported in the literature. With our large dataset, we examine correlations between HR and multiple host-galaxy properties simultaneously and find no evidence of a significant correlation. We also independently analyze our spectroscopically-confirmed and photometrically-classified SNe Ia and comment on the significance of similar combined datasets for future surveys. 3. Providing stringent star formation rate limits of z\\sim$2 QSO host galaxies at high angular resolution Vayner, Andrey; Do, Tuan; Larkin, James E; Armus, Lee; Gallagher, Sarah C 2014-01-01 We present integral field spectrograph (IFS) with laser guide star adaptive optics (LGS-AO) observations of z=2 quasi-stellar objects (QSOs) designed to resolve extended nebular line emission from the host galaxy. Our data was obtained with W. M. Keck and Gemini-North Observatories using OSIRIS and NIFS coupled with the LGS-AO systems. We have conducted a pilot survey of five QSOs, three observed with NIFS+AO and two observed with OSIRIS+AO at an average redshift of z=2.15. We demonstrate that the combination of AO and IFS provides the necessary spatial and spectral resolutions required to separate QSO emission from its host. We present our technique for generating a PSF from the broad-line region of the QSO and performing PSF subtraction of the QSO emission to detect the host galaxy. We detect H$\\alpha$and [NII] for two sources, SDSS J1029+6510 and SDSS J0925+06 that have both star formation and extended narrow-line emission. Assuming that the majority of narrow-line H$\\alpha$is from star formation, we inf... 4. EmpiriciSN: Re-sampling Observed Supernova/Host Galaxy Populations Using an XD Gaussian Mixture Model Holoien, Thomas W.-S.; /Ohio State U., Dept. Astron. /Ohio State U., CCAPP /KIPAC, Menlo Park /SLAC; Marshall, Philip J.; Wechsler, Risa H.; /KIPAC, Menlo Park /SLAC 2017-05-11 We describe two new open-source tools written in Python for performing extreme deconvolution Gaussian mixture modeling (XDGMM) and using a conditioned model to re-sample observed supernova and host galaxy populations. XDGMM is new program that uses Gaussian mixtures to perform density estimation of noisy data using extreme deconvolution (XD) algorithms. Additionally, it has functionality not available in other XD tools. It allows the user to select between the AstroML and Bovy et al. fitting methods and is compatible with scikit-learn machine learning algorithms. Most crucially, it allows the user to condition a model based on the known values of a subset of parameters. This gives the user the ability to produce a tool that can predict unknown parameters based on a model that is conditioned on known values of other parameters. EmpiriciSN is an exemplary application of this functionality, which can be used to fit an XDGMM model to observed supernova/host data sets and predict likely supernova parameters using a model conditioned on observed host properties. It is primarily intended to simulate realistic supernovae for LSST data simulations based on empirical galaxy properties. 5. EmpiriciSN: Re-sampling Observed Supernova/Host Galaxy Populations Using an XD Gaussian Mixture Model Holoien, Thomas W.-S.; Marshall, Philip J.; Wechsler, Risa H. 2017-06-01 We describe two new open-source tools written in Python for performing extreme deconvolution Gaussian mixture modeling (XDGMM) and using a conditioned model to re-sample observed supernova and host galaxy populations. XDGMM is new program that uses Gaussian mixtures to perform density estimation of noisy data using extreme deconvolution (XD) algorithms. Additionally, it has functionality not available in other XD tools. It allows the user to select between the AstroML and Bovy et al. fitting methods and is compatible with scikit-learn machine learning algorithms. Most crucially, it allows the user to condition a model based on the known values of a subset of parameters. This gives the user the ability to produce a tool that can predict unknown parameters based on a model that is conditioned on known values of other parameters. EmpiriciSN is an exemplary application of this functionality, which can be used to fit an XDGMM model to observed supernova/host data sets and predict likely supernova parameters using a model conditioned on observed host properties. It is primarily intended to simulate realistic supernovae for LSST data simulations based on empirical galaxy properties. 6. The Effects of X-Ray Feedback from AGN on Host Galaxy Evolution Hambrick, D Clay; Naab, Thorsten; Johansson, Peter H 2011-01-01 Hydrodynamic simulations of galaxies with active galactic nuclei (AGN) have typically employed feedback that is purely local: i.e., an injection of energy to the immediate neighborhood of the black hole. We perform GADGET-2 simulations of massive elliptical galaxies with an additional feedback component: an observationally calibrated X-ray radiation field which emanates from the black hole and heats gas out to large radii from the galaxy center. We find that including the heating and radiation pressure associated with this X-ray flux in our simulations enhances the effects which are commonly reported from AGN feedback. This new feedback model is twice as effective as traditional feedback at suppressing star formation, produces 3 times less star formation in the last 6 Gyr, and modestly lowers the final BH mass (30%). It is also significantly more effective than an X-ray background in reducing the number of satellite galaxies. 7. Hubble Space Telescope Observations of the Afterglow, Supernova and Host Galaxy Associated with the Extremely Bright GRB 130427A Levan, A.J.; Tanvir, N. R.; Fruchter, A. S.; Hjorth, J.; Pian, E.; Mazzali, P.; Hounsell, R. A.; Perley, D. A.; Cano, Z.; Graham, J.; 2014-01-01 We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst, GRB 130427A. At z=0.34 this burst affords an excellent opportunity to study the supernova and host galaxy associated with an intrinsically extremely luminous burst (E(sub iso) greater than 10(exp 54) erg): more luminous than any previous GRB with a spectroscopically associated supernova. We use the combination of the image quality, UV capability and and invariant PSF of HST to provide the best possible separation of the afterglow, host and supernova contributions to the observed light approximately 17 rest-frame days after the burst utilising a host subtraction spectrum obtained 1 year later. Advanced Camera for Surveys (ACS) grism observations show that the associated supernova, SN 2013cq, has an overall spectral shape and luminosity similar to SN 1998bw (with a photospheric velocity, vph approximately 15,000 kilometers per second). The positions of the bluer features are better matched by the higher velocity SN 2010bh (vph approximately 30,000 kilometers per second), but SN 2010bh (vph approximately 30,000 kilometers per second but this SN is significantly fainter, and fails to reproduce the overall spectral shape, perhaps indicative of velocity structure in the ejecta. We find that the burst originated approximately 4 kpc from the nucleus of a moderately star forming (1 Solar Mass yr(exp-1)), possibly interacting disc galaxy. The absolute magnitude, physical size and morphology of this galaxy, as well as the location of the GRB within it are also strikingly similar to those of GRB980425SN 1998bw. The similarity of supernovae and environment from both the most luminous and least luminous GRBs suggests broadly similar progenitor stars can create GRBs across six orders of magnitude in isotropic energy. 8. Levan, A. J. [Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Tanvir, N. R.; Wiersema, K. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom); Fruchter, A. S.; Hounsell, R. A.; Graham, J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Hjorth, J.; Fynbo, J. P. U. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Pian, E. [INAF, Trieste Astronomical Observatory, via G.B. Tiepolo 11, I-34143 Trieste (Italy); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, IC2 Liverpool Science Park 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Perley, D. A. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Blvd., Pasadena, CA 91125 (United States); Cano, Z. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavik (Iceland); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Kouveliotou, C. [Science and Technology Office, ZP12, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Pe' er, A. [Department of Physics, University College Cork, Cork (Ireland); Misra, K., E-mail: [email protected] [Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital-263 002 (India) 2014-09-10 We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst (GRB), GRB 130427A. At z = 0.34, this burst affords an excellent opportunity to study the supernova (SN) and host galaxy associated with an intrinsically extremely luminous burst (E {sub iso} > 10{sup 54} erg): more luminous than any previous GRB with a spectroscopically associated SN. We use the combination of the image quality, UV capability, and invariant point-spread function of HST to provide the best possible separation of the afterglow, host, and SN contributions to the observed light ∼17 rest-frame days after the burst, utilizing a host subtraction spectrum obtained one year later. Advanced Camera for Surveys grism observations show that the associated SN, SN 2013cq, has an overall spectral shape and luminosity similar to SN 1998bw (with a photospheric velocity, v {sub ph} ∼ 15, 000 km s{sup –1}). The positions of the bluer features are better matched by the higher velocity SN 2010bh (v {sub ph} ∼ 30, 000 km s{sup –1}), but this SN is significantly fainter and fails to reproduce the overall spectral shape, perhaps indicative of velocity structure in the ejecta. We find that the burst originated ∼4 kpc from the nucleus of a moderately star forming (1 M {sub ☉} yr{sup –1}), possibly interacting disk galaxy. The absolute magnitude, physical size, and morphology of this galaxy, as well as the location of the GRB within it, are also strikingly similar to those of GRB 980425/SN 1998bw. The similarity of the SNe and environment from both the most luminous and least luminous GRBs suggests that broadly similar progenitor stars can create GRBs across six orders of magnitude in isotropic energy. 9. Host galaxies of luminous z$\\sim$0.6 quasars: Major mergers are not prevalent at the highest AGN luminosities Villforth, C; Pawlik, M M; Hewlett, T; Rowlands, K; Herbst, H; Shankar, F; Fontana, A; Hamann, F; Koekemoer, A; Pforr, J; Trump, J; Wuyts, S 2016-01-01 Galaxy interactions are thought to be one of the main triggers of Active Galactic Nuclei (AGN), especially at high luminosities, where the accreted gas mass during the AGN lifetime is substantial. Evidence for a connection between mergers and AGN, however, remains mixed. Possible triggering mechanisms remain particularly poorly understood for luminous AGN, which are thought to require triggering by major mergers, rather than secular processes. We analyse the host galaxies of a sample of 20 optically and X-ray selected luminous AGN (log($L_{bol}$[erg/s])$>$45) at z$\\sim$0.6 using HST WFC3 data in the F160W/H band. 15/20 sources have resolved host galaxies. We create a control sample of mock AGN by matching the AGN host galaxies to a control sample of non-AGN galaxies. Visual signs of disturbances are found in about 25% of sources in both the AGN hosts and control galaxies. Using both visual classification and quantitative morphology measures, we show that the levels of disturbance are not enhanced when co... 10. The hydrogen-poor superluminous supernova iPTF 13ajg and its host galaxy in absorption and emission Vreeswijk, Paul M.; Gal-Yam, Avishay; De Cia, Annalisa; Rubin, Adam; Yaron, Ofer; Tal, David; Ofek, Eran O. [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 7610001 (Israel); Savaglio, Sandra [Max Planck Institute for Extraterrestrial Physics, D-85748 Garching bei München (Germany); Quimby, Robert M. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, The University of Tokyo 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8583 (Japan); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Cenko, S. Bradley; Filippenko, Alexei V.; Clubb, Kelsey I. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Perley, Daniel A.; Cao, Yi [Astronomy Department, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Taddia, Francesco; Sollerman, Jesper; Leloudas, Giorgos [Department of Astronomy, The Oskar Klein Center, Stockholm University, AlbaNova 10691 Stockholm (Sweden); Arcavi, Iair [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Goleta, CA 93117 (United States); Kasliwal, Mansi M., E-mail: [email protected] [The Observatories, Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); and others 2014-12-10 We present imaging and spectroscopy of a hydrogen-poor superluminous supernova (SLSN) discovered by the intermediate Palomar Transient Factory, iPTF 13ajg. At a redshift of z = 0.7403, derived from narrow absorption lines, iPTF 13ajg peaked at an absolute magnitude of M {sub u,} {sub AB} = –22.5, one of the most luminous supernovae to date. The observed bolometric peak luminosity of iPTF 13ajg is 3.2 × 10{sup 44} erg s{sup –1}, while the estimated total radiated energy is 1.3 × 10{sup 51} erg. We detect narrow absorption lines of Mg I, Mg II, and Fe II, associated with the cold interstellar medium in the host galaxy, at two different epochs with X-shooter at the Very Large Telescope. From Voigt profile fitting, we derive the column densities log N(Mg I) =11.94 ± 0.06, log N(Mg II) =14.7 ± 0.3, and log N(Fe II) =14.25 ± 0.10. These column densities, as well as the Mg I and Mg II equivalent widths of a sample of hydrogen-poor SLSNe taken from the literature, are at the low end of those derived for gamma-ray bursts (GRBs) whose progenitors are also thought to be massive stars. This suggests that the environments of hydrogen-poor SLSNe and GRBs are different. From the nondetection of Fe II fine-structure absorption lines, we derive a lower limit on the distance between the supernova and the narrow-line absorbing gas of 50 pc. The neutral gas responsible for the absorption in iPTF 13ajg exhibits a single narrow component with a low velocity width, ΔV = 76 km s{sup –1}, indicating a low-mass host galaxy. No host galaxy emission lines are detected, leading to an upper limit on the unobscured star formation rate (SFR) of SFR{sub [O} {sub II]}<0.07M{sub ⊙}yr{sup −1}. Late-time imaging shows the iPTF 13ajg host galaxy to be faint, with g {sub AB} ≈ 27.0 and R {sub AB} ≥ 26.0 mag, corresponding to M {sub B,} {sub Vega} ≳ –17.7 mag. 11. The Type Ia Supernova Color-Magnitude Relation and Host Galaxy Dust: A Simple Hierarchical Bayesian Model Mandel, Kaisey; Scolnic, Daniel; Shariff, Hikmatali; Foley, Ryan; Kirshner, Robert 2017-01-01 Inferring peak optical absolute magnitudes of Type Ia supernovae (SN Ia) from distance-independent measures such as their light curve shapes and colors underpins the evidence for cosmic acceleration. SN Ia with broader, slower declining optical light curves are more luminous (“broader-brighter”) and those with redder colors are dimmer. But the “redder-dimmer” color-luminosity relation widely used in cosmological SN Ia analyses confounds its two separate physical origins. An intrinsic correlation arises from the physics of exploding white dwarfs, while interstellar dust in the host galaxy also makes SN Ia appear dimmer and redder. Conventional SN Ia cosmology analyses currently use a simplistic linear regression of magnitude versus color and light curve shape, which does not model intrinsic SN Ia variations and host galaxy dust as physically distinct effects, resulting in low color-magnitude slopes. We construct a probabilistic generative model for the dusty distribution of extinguished absolute magnitudes and apparent colors as the convolution of an intrinsic SN Ia color-magnitude distribution and a host galaxy dust reddening-extinction distribution. If the intrinsic color-magnitude (MB vs. B-V) slope βint differs from the host galaxy dust law RB, this convolution results in a specific curve of mean extinguished absolute magnitude vs. apparent color. The derivative of this curve smoothly transitions from βint in the blue tail to RB in the red tail of the apparent color distribution. The conventional linear fit approximates this effective curve near the average apparent color, resulting in an apparent slope βapp between βint and RB. We incorporate these effects into a hierarchical Bayesian statistical model for SN Ia light curve measurements, and analyze a dataset of SALT2 optical light curve fits of 277 nearby SN Ia at z < 0.10. The conventional linear fit obtains βapp ≈ 3. Our model finds a βint = 2.2 ± 0.3 and a distinct dust law of RB = 3.7 ± 0 12. IDENTIFYING THE LOCATION IN THE HOST GALAXY OF THE SHORT GRB 111117A WITH THE CHANDRA SUBARCSECOND POSITION Sakamoto, T.; Troja, E. [Center for Research and Exploration in Space Science and Technology (CRESST), NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Aoki, K. [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A' ohoku Place, Hilo, HI 96720 (United States); Guiriec, S.; Barthelmy, S. D. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Im, M.; Jeon, Y. [Center for the Exploration of the Origin of the Universe (CEOU), Department of Physics and Astronomy, Seoul National University, Seoul, 151-747 (Korea, Republic of); Leloudas, G.; Malesani, D.; De Ugarte Postigo, A.; Andersen, M. I. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Melandri, A.; D' Avanzo, P. [INAF-Osservatorio Astronomico di Brera, via Bianchi 46, I-23807 Merate (Italy); Urata, Y. [Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan (China); Xu, D. [Department of Particle Physics and Astronomy, The Weizmann Institute of Science, Rehovot 76100 (Israel); Gorosabel, J.; Sanchez-Ramirez, R. [Instituto de Astrofisica de Andalucia (CSIC), Glorieta de la Astronomia s/n, E-18008 Granada (Spain); Bai, J. [Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming, Yunnan Province, 650011 (China); Briggs, M. S. [Center for Space Plasma and Aeronomic Research, University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Foley, S. [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); and others 2013-03-20 We present our successful Chandra program designed to identify, with subarcsecond accuracy, the X-ray afterglow of the short GRB 111117A, which was discovered by Swift and Fermi. Thanks to our rapid target of opportunity request, Chandra clearly detected the X-ray afterglow, though no optical afterglow was found in deep optical observations. The host galaxy was clearly detected in the optical and near-infrared band, with the best photometric redshift of z=1.31{sub -0.23}{sup +0.46} (90% confidence), making it one of the highest known short gamma-ray burst (GRB) redshifts. Furthermore, we see an offset of 1.0 {+-} 0.2 arcsec, which corresponds to 8.4 {+-} 1.7 kpc, between the host and the afterglow position. We discuss the importance of using Chandra for obtaining subarcsecond X-ray localizations of short GRB afterglows to study GRB environments. 13. K-band Imaging of strong CaII-absorber host galaxies at z~1 Hewett, Paul 2007-01-01 We present K-band imaging of fields around 30 strong CaII absorption line systems, at 0.7galaxies is found within 6"0 (~50kpc) from the absorber line-of-sight. The excess galaxies are preferentially luminous compared to the population of field galaxies. A model in which field galaxies possess a luminosity-dependent cross-section for CaII absorption of the form (L/L*)^0.7 reproduces the observations well. The luminosity-dependent cross-section for the CaII absorbers appears to be significantly stronger than the established (L/L*)^0.4 dependence for MgII absorbers. The associated galaxies lie at large physical distances from the CaII-absorbing gas; we find a mean impact parameter of 24kpc (H0=70km\\s\\Mpc). Combined with the observed number density of CaII absorbers the large physical separations result in an inferred filling factor of only ~10 per cent. The physical origin of the strong CaII absorption remains unclear,... 14. Evidence of suppression of star formation by quasar-driven winds in gas-rich host galaxies at z<1? Wylezalek, Dominika 2016-01-01 Feedback from active galactic nuclei (AGN) is widely considered to be the main driver in regulating the growth of massive galaxies through heating or driving gas out of the galaxy, preventing further increase in stellar mass. Observational proof for this scenario has, however, been scarce. We have assembled a sample of 132 radio-quiet type-2 and red AGN at 0.1host galaxies' stellar masses and star formation rates and investigate the relationships between AGN luminosities, specific star formation rates (sSFR) and outflow strengths W90 -- the 90\\% velocity width of the [OIII]5007 line power and a proxy for the AGN-driven outflow speed. Outflow strength is independent of sSFR for AGN selected on their mid-IR luminosity, in agreement with previous work demonstrating that star formation is not sufficient to produce the observed ionized gas outflows which have to be powered by AGN activity. More importantly, we find a negative correlation between W90... 15. Bright [CII] 158$\\mu$m emission in a quasar host galaxy at$z=6.54$Bañados, E; Walter, F; Venemans, B P; Farina, E P; Fan, X 2015-01-01 The [CII] 158$\\mu$m fine-structure line is known to trace regions of active star formation and is the main coolant of the cold, neutral atomic medium. In this \\textit{Letter}, we report a strong detection of the [CII] line in the host galaxy of the brightest quasar known at$z>6.5$, the Pan-STARRS1 selected quasar PSO J036.5078+03.0498 (hereafter P036+03), using the IRAM NOEMA millimeter interferometer. Its [CII] and total far-infrared luminosities are$(5.8 \\pm 0.7) \\times 10^9 \\,L_\\odot$and$(7.6\\pm1.5) \\times 10^{12}\\,L_\\odot$, respectively. This results in a$L_{[CII]} /L_{TIR}$ratio of$\\sim 0.8\\times 10^{-3}$, which is at the high end for those found for active galaxies, though it is lower than the average found in typical main sequence galaxies at$z\\sim 0$. We also report a tentative additional line which we identify as a blended emission from the$3_{22} - 3_{13}$and$5_{23} - 4_{32}$H$_2$O transitions. If confirmed, this would be the most distant detection of water emission to date. P036+03 riva... 16. A Merger Origin for Short Gamma-Ray Bursts Inferred from the Afterglow and Host Galaxy of GRB 050724 Berger, E; Cenko, S B; Gal-Yam, A; Soderberg, A M; Kasliwal, M; Leonard, D C; Cameron, P B; Frail, D A; Kulkarni, S R; Murphy, D C; Krzeminski, W; Piran, T; Lee, B L; Roth, K C; Moon, D S; Fox, D B; Harrison, F A; Persson, S E; Schmidt, B P; Penprase, B E; Rich, J; Peterson, B A; Cowie, L L 2005-01-01 Despite a rich phenomenology, gamma-ray bursts (GRBs) are divided into two classes based on their duration and spectral hardness -- the long-soft and the short-hard bursts. The discovery of afterglow emission from long GRBs was a watershed event, pinpointing their origin to star forming galaxies, and hence the death of massive stars, and indicating an energy release of about 10^51 erg. While theoretical arguments suggest that short GRBs are produced in the merger of compact object binaries (neutron stars or black holes), the progenitors, energetics, and environments of these events remain elusive despite recent localizations. Here we report the discovery of radio, optical, and infrared afterglow emission from the short-hard GRB 050724, which unambiguously associate it with an elliptical galaxy at a redshift, z=0.257. We show that the energy release is 1-3 orders of magnitude smaller than that of long GRBs, and that the burst ejecta may be collimated in jets. More importantly, the nature of the host galaxy for... 17. The Swift GRB Host Galaxy Legacy Survey - II. Rest-Frame NIR Luminosity Distribution and Evidence for a Near-Solar Metallicity Threshold Perley, D A; Hjorth, J; Laskar, T; Berger, E; Chary, R; Postigo, A de Ugarte; Fynbo, J P U; Krühler, T; Levan, A J; Michałowski, M J; Schulze, S 2016-01-01 We present rest-frame NIR luminosities and stellar masses for a large and uniformly-selected population of GRB host galaxies using deep Spitzer Space Telescope imaging of 117 targets from the Swift GRB Host Galaxy Legacy Survey spanning 0.03 2; metals stifle GRB production in most galaxies at z<1.5 but have only minor impact at higher redshifts. The metallicity threshold we infer is much higher than predicted by single-star models and favors a binary progenitor. Our observations also constrain the fraction of cosmic star-formation in low-mass galaxies undetectable to Spitzer to be a small minority at most redshifts (~10% at z~2, ~25% at z~3, and ~50% at z=3.5-6.0). 18. ALMA Observations Show Major Mergers Among the Host Galaxies of Fast-growing, High-redshift Supermassive Black Holes Trakhtenbrot, Benny; Lira, Paulina; Netzer, Hagai; Cicone, Claudia; Maiolino, Roberto; Shemmer, Ohad 2017-02-01 We present new ALMA band-7 data for a sample of six luminous quasars at z≃ 4.8, powered by fast-growing supermassive black holes (SMBHs) with rather uniform properties: the typical accretion rates and black hole masses are L/{L}{Edd}≃ 0.7 and {M}{BH}≃ {10}9 {M}ȯ . Our sample consists of three “FIR-bright” sources, which were individually detected in previous Herschel/SPIRE observations, with star formation rates of {SFR}> 1000 {M}ȯ {{yr}}-1, and three “FIR-faint” sources for which Herschel stacking analysis implies a typical SFR of ∼400 {M}ȯ {{yr}}-1. The dusty interstellar medium in the hosts of all six quasars is clearly detected in the ALMA data and resolved on scales of ∼2 kpc, in both continuum ({λ }{rest}∼ 150 μ {{m}}) and [{{C}} {{II}}] λ 157.74 μ {{m}} line emission. The continuum emission is in good agreement with the expectations from the Herschel data, confirming the intense SF activity in the quasar hosts. Importantly, we detect companion sub-millimeter galaxies (SMGs) for three sources—one FIR-bright and two FIR-faint, separated by ∼ 14{--}45 {kpc} and ALMA data therefore clearly support the idea that major mergers are important drivers for rapid early SMBH growth. However, the fact that not all high-SFR quasar hosts are accompanied by interacting SMGs and the gas kinematics as observed by ALMA suggest that other processes may be fueling these systems. Our analysis thus demonstrates the diversity of host galaxy properties and gas accretion mechanisms associated with early and rapid SMBH growth. 19. Origin of X-shaped radio-sources: further insights from the properties of their host galaxies Gillone, M.; Capetti, A.; Rossi, P. 2016-03-01 We analyze the properties of a sample of X-shaped radio-sources (XRSs). These objects show, in addition to the main lobes, a pair of wings that produce their peculiar radio morphology. We obtain our sample by selecting from the initial list of Cheung (2007, AJ, 133, 2097) the 53 galaxies with the better defined wings and with available SDSS images. We identify the host galaxies and measure their optical position angle, obtaining a positive result in 22 cases. The orientation of the secondary radio structures shows a strong connection with the optical axis, with all (but one) wing forming an angle larger than 40° with the host major axis. The probability that this is compatible with a uniform distribution is P = 0.9 × 10-4. For all but three sources of the sample, spectroscopic or photometric redshifts are avaliable. The radio luminosity distribution of XRSs has a high power cut-off at L ˜ 1034 erg s-1 Hz-1 at 1.4 GHz. Spectra are available from the SDSS for 28 XRSs. We modeled them to extract information on their emission lines and stellar population properties. The sample is formed by approximately the same number of high and low excitation galaxies (HEGs and LEGs); this classification is essential for a proper comparison with non-winged radio-galaxies. XRSs follow the same relations between radio and line luminosity defined by radio-galaxies in the 3C sample. While in HEGs a young stellar population is often present, this is not detected in the 13 LEGs, which is, again, in agreement with the properties of non-XRSs. The lack of young stars in LEGs supports the idea that they have not experienced a recent gas-rich merger. The connection between the optical axis and the wing orientation, as well as the stellar population and emission-line properties, provide further support for a hydro-dynamic origin of the radio-wings (for example, associated with the expansion of the radio cocoon in an asymmetric external medium) rather than with a change of orientation of the 20. The extraordinarily bright optical afterglow of GRB 991208 and its host galaxy Castro-Tirado, A.J.; Sokolov, V.V.; Gorosabel, J.; 2001-01-01 a massive star origin. The absolute magnitude of the galaxy is M-B = -18.2, well below the knee of the galaxy luminosity function and we derive a star-forming rate of (11.5 +/- 7.1) M-circle dot yr(-1), which is much larger than the present-day rate in our Galaxy. The quasi simultaneous broad......-band photometric spectral energy distribution of the afterglow was determined similar to3.5 day after the burst (Dec. 12.0) implying a cooling frequency ve below the optical band, i.e. supporting a jet model with p = -2.30 as the index of the power-law electron distribution.... 1. Red bulgeless galaxies in SDSS DR7. Are there any AGN hosts? Coelho, Bruno; Lobo, Catarina; Ribeiro, Bruno 2013-01-01 With the main goal of finding bulgeless galaxies harbouring super massive black holes and showing, at most, just residual star formation activity, we have selected a sample of massive bulgeless red sequence galaxies from the SDSS-DR7, based on the NYU-VAGC catalogue. Multivavelength data were retrieved using EURO-VO tools, and the objects are characterised in terms of degree of star formation and the presence of an AGN. We have found seven objects that are quenched massive galaxies, that have no prominent bulge and that show signs of extra activity in their nuclei, five of them being central in their halo. These objects are rather robust candidates for rare systems that, though devoid of a significant bulge, harbor a supermassive black hole with an activity level likely capable of having halted the star formation through feedback. 2. Properties and environment of Radio Emitting Galaxies in the VLA-zCOSMOS survey Bardelli, S; Smolcic, V; Zamorani, G; Zucca, E; Mignoli, M; Halliday, C; Kovac, K; Ciliegi, P; Caputi, K; Koekemoer, A M; Bongiorno, A; Bondi, M; Bolzonella, M; Vergani, D; Pozzetti, L; Carollo, C M; Contini, T; Kneib, J -P; LeFevre, O; Lilly, S; Mainieri, V; Renzini, A; Scodeggio, M; Coppa, G; Cucciati, O; delaTorre, S; deRavel, L; Franzetti, P; Garilli, B; Iovino, A; Kampczyk, P; Knobel, C; Lamareille, F; LeBorgne, J -F; Le Brun, V; Maier, C; Pello, R; Peng, Y; Pérez-Montero, E; Ricciardelli, E; Silverman, J D; Tanaka, M; Tasca, L; Tresse, L; Abbas, U; Bottini, D; Cappi, A; Cassata, P; Cimatti, A; Guzzo, L; Leauthaud, A; MacCagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Scaramella, R; Capak, P; Sanders, D; Scoville, N; Taniguchi, Y; Jahnke, K 2009-01-01 We investigate the properties and the environment of radio sources with optical counterpart from the combined VLA-COSMOS and zCOSMOS samples. The advantage of this sample is the availability of optical spectroscopic information, high quality redshifts, and accurate density determination. By comparing the star formation rates estimated from the optical spectral energy distribution with those based on the radio luminosity, we divide the radio sources in three families, passive AGN, non-passive AGN and star forming galaxies. These families occupy specific regions of the 8.0-4.5$\\mu$m infrared color--specific star formation plane, from which we extract the corresponding control samples. Only the passive AGN have a significantly different environment distribution from their control sample. The fraction of radio-loud passive AGN increases from ~2% in underdense regions to ~15% for overdensities (1+delta) greater than 10. This trend is also present as a function of richness of the groups hosting the radio sources. ... 3. Reaching the Peak of the quasar spectral energy distribution - II. Exploring the accretion disc, dusty torus and host galaxy Collinson, James S; Landt, Hermine; Done, Chris; Elvis, Martin; McDowell, Jonathan C 2016-01-01 We continue our study of the spectral energy distributions (SEDs) of 11 AGN at 1.5 < z < 2.2, with optical-NIR spectra, X-ray data and mid-IR photometry. In a previous paper we presented the observations and models; in this paper we explore the parameter space of these models. We first quantify uncertainties on the black hole masses (M$_{\\rm BH}$) and degeneracies between SED parameters. The effect of BH spin is tested, and we find that while low to moderate spin values (a$_*\\leq$0.9) are compatible with the data in all cases, maximal spin (a$_*$= 0.998) can only describe the data if the accretion disc is face-on. The outer accretion disc radii are well constrained in 8/11 objects, and are found to be a factor ~5 smaller than the self-gravity radii. We then extend our modelling campaign into the mid-IR regime with WISE photometry, adding components for the host galaxy and dusty torus. Our estimates of the host galaxy luminosities are consistent with the M$_{\\rm BH}$-bulge relationship, and the meas... 4. Reaching the peak of the quasar spectral energy distribution - II. Exploring the accretion disc, dusty torus and host galaxy Collinson, James S.; Ward, Martin J.; Landt, Hermine; Done, Chris; Elvis, Martin; McDowell, Jonathan C. 2017-02-01 We continue our study of the spectral energy distributions (SEDs) of 11 active galactic nuclei (AGN) at 1.5 maximal spin (a* = 0.998) can only describe the data if the accretion disc is face-on. The outer accretion disc radii are well constrained in 8/11 objects and are found to be a factor ˜5 smaller than the self-gravity radii. We then extend our modelling campaign into the mid-IR regime with Wide-field Infrared Survey Explorer photometry, adding components for the host galaxy and dusty torus. Our estimates of the host galaxy luminosities are consistent with the MBH-bulge relationship, and the measured torus properties (covering factor and temperature) are in agreement with earlier work, suggesting a predominantly silicate-based grain composition. Finally, we deconvolve the optical-NIR spectra using our SED continuum model. We claim that this is a more physically motivated approach than using empirical descriptions of the continuum such as broken power laws. For our small sample, we verify previously noted correlations between emission linewidths and luminosities commonly used for single-epoch MBH estimates, and observe a statistically significant anticorrelation between [O III] equivalent width and AGN luminosity. 5. MUSE Reveals a Recent Merger in the Post-starburst Host Galaxy of the TDE ASASSN-14li Prieto, J L; Anderson, J P; Galbany, L; Kochanek, C S; Aquino, E; Brown, J S; Dong, Subo; Förster, F; Holoien, T W -S; Kuncarayakti, H; Maureira, J C; Rosales-Ortega, F F; Sánchez, S F; Shappee, B J; Stanek, K Z 2016-01-01 We present MUSE integral field spectroscopic observations of the host galaxy (PGC 043234) of one of the closest ($z=0.0206$,$D\\simeq 90$Mpc) and best-studied tidal disruption events (TDE), ASASSN-14li. The MUSE integral field data reveal asymmetric and filamentary structures that extend up to$\\gtrsim 10$kpc from the post-starburst host galaxy of ASASSN-14li. The structures are traced only through the strong nebular [O III]$\\lambda$5007, [N II]$\\lambda$6584, and H$\\alpha$emission lines. The total off nuclear [O III]$\\lambda$5007 luminosity is luminosity is$4.7\\times 10^{39}$erg s$^{-1}$and the ionized H mass is$\\rm \\sim 10^4(500/n_e)\\,M_{\\odot}$. Based on the BPT diagram, the nebular emission can be driven by either AGN photoionization or shock excitation, with AGN photoionization favored given the narrow intrinsic line widths. The emission line ratios and spatial distribution strongly resemble ionization nebulae around fading AGNs such as IC 2497 (Hanny's Voorwerp) and ionization "cones" around Se... 6. The very red afterglow of GRB 000418: Further evidence for dust extinction in a gamma-ray burst host galaxy Klose, S.; Stecklum, B.; Masetti, N.; 2000-01-01 We report near-infrared and optical follow-up observations of the afterglow of the GRB 000418 starting 2.5 days after the occurrence of the burst and extending over nearly 7 weeks. GRB 000418 represents the second case for which the afterglow was initially identified by observations in the near-i......) bursts are associated with events in star-forming regions.......-infrared. During the first 10 days its R-band afterglow was well characterized by a single power-law decay with a slope of 0.86. However, at later times the temporal evolution of the afterglow flattens with respect to a simple power-law decay. Attributing this to an underlying host galaxy, we find its magnitude...... to be R = 23.9 and an intrinsic afterglow decay slope of 1.22. The afterglow was very red with R-K approximate to 4 mag. The observations can be explained by an adiabatic, spherical fireball solution and a heavy reddening due to dust extinction in the host galaxy. This supports the picture that (long... 7. Observation of Weak Low-ionization Winds in Host Galaxies of Low Luminosity Active Galactic Nuclei at z ~1 Yesuf, Hassen; David C. Koo, S. M. Faber, J. Xavier Prochaska, Yicheng Guo, F. S. Liu, Emily C. Cunningham, Alison L. Coil, Puragra Guhathakurta 2017-01-01 A key physical manifestation of active galactic nuclei (AGN) feedback is predicted to be powerful galactic winds. However, the relative roles between AGN activity and star formation in driving such winds remain largely unexplored at high redshifts, near the peak of cosmic activity for both. We study winds in 12 X-ray AGN host galaxies at z ~ 1 in the CANDELS fields using deep Keck rest-frame UV spectroscopy. We find, using the low-ionization Fe II 2586 absorption in the stacked spectra, that the AGN show a median centroid velocity shift of -137 km/s and a median velocity dispersion of 103 km/ s. The centroid velocity and the velocity dispersions are obtained from a two component (ISM+wind) absorption line model. For comparison, a star-forming and X-ray undetected galaxies at a similar redshift, matched roughly in stellar mass and galaxy inclination, show the outflows to have a median centroid velocity of -135 km/s and a median velocity dispersion of 140 km/s. Thus, winds in the AGN are similar in velocities to those found in star-formation-driven winds, and are weak to escape and expel substantial cool gas from galaxies. A joint reanalysis of the z ~ 0.5 AGN sample and our sample yields a centroid velocity of -139 (+48, -87) km/s and a velocity dispersion of 82 (+47,-37) km/s. For the combined sample, about half the total equivalent width of the Fe II 2586 absorption is due to the wind. We do not observe winds with bulk velocities greater than 500 km/s predicted by some AGN feedback models. 8. ALMA observations of the host galaxy of GRB 090423 at z = 8.23: deep limits on obscured star formation 630 million years after the big bang Berger, E.; Zauderer, B. A.; Chary, R.-R.; Laskar, T.; Chornock, R.; Davies, J. E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Stanway, E. R.; Levan, A. J. [Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom); Levesque, E. M. [CASA, University of Colorado UCB 389, Boulder, CO 80309 (United States) 2014-12-01 We present rest-frame far-infrared (FIR) and optical observations of the host galaxy of GRB 090423 at z = 8.23 from the Atacama Large Millimeter Array (ALMA) and the Spitzer Space Telescope, respectively. The host remains undetected to 3σ limits of F {sub ν}(222 GHz) ≲ 33 μJy and F {sub ν}(3.6 μm) ≲ 81 nJy. The FIR limit is about 20 times fainter than the luminosity of the local ULIRG Arp 220 and comparable to the local starburst M 82. Comparing this with model spectral energy distributions, we place a limit on the infrared (IR) luminosity of L {sub IR}(8-1000 μm) ≲ 3 × 10{sup 10} L {sub ☉}, corresponding to a limit on the obscured star formation rate of SFR{sub IR}≲5 M {sub ☉} yr{sup –1}. For comparison, the limit on the unobscured star formation rate from Hubble Space Telescope rest-frame ultraviolet (UV) observations is SFR{sub UV} ≲ 1 M {sub ☉} yr{sup –1}. We also place a limit on the host galaxy stellar mass of M {sub *} ≲ 5 × 10{sup 7} M {sub ☉} (for a stellar population age of 100 Myr and constant star formation rate). Finally, we compare our millimeter observations to those of field galaxies at z ≳ 4 (Lyman break galaxies, Lyα emitters, and submillimeter galaxies) and find that our limit on the FIR luminosity is the most constraining to date, although the field galaxies have much larger rest-frame UV/optical luminosities than the host of GRB 090423 by virtue of their selection techniques. We conclude that GRB host galaxies at z ≳ 4, especially those with measured interstellar medium metallicities from afterglow spectroscopy, are an attractive sample for future ALMA studies of high redshift obscured star formation. 9. The Connection between Globular Cluster Systems and their Host Galaxy and Environment: A Case Study of the Isolated Elliptical NGC 821 Spitler, Lee R; Strader, Jay; Brodie, Jean P; Gallagher, Jay S 2007-01-01 In an effort to probe the globular cluster (GC) system of an isolated elliptical galaxy, a comprehensive analysis of the NGC 821 GC system was performed. New imaging from the WIYN Mini-Mosaic imager, supplemented with HST WFPC2 images reveals a GC system similar to those found in counterpart ellipticals located in high density environments. To put these results into the context of galaxy formation, a robustly-determined census of GC systems is presented and analysed for galaxies spanning a wide range of masses (> M_star), morphologies and environments. Results from this meta-study: (1) confirm previous findings that the number of GCs normalized by host galaxy stellar mass increases with host stellar mass. Spiral galaxies in the sample show smaller relative GC numbers than those of massive ellipticals, suggesting the GC systems of massive ellipticals were not formed from major spiral-spiral mergers; (2) indicate that GC system numbers per unit galaxy baryon mass increases with host baryon mass and that GC form... 10. Optical Identification of Cepheids in 19 Host Galaxies of Type Ia Supernovae and NGC 4258 with the Hubble Space Telescope Hoffmann, Samantha L.; Macri, Lucas M.; Riess, Adam G.; Yuan, Wenlong; Casertano, Stefano; Foley, Ryan J.; Filippenko, Alexei V.; Tucker, Brad E.; Chornock, Ryan; Silverman, Jeffrey M.; Welch, Douglas L.; Goobar, Ariel; Amanullah, Rahman 2016-10-01 We present results of an optical search conducted as part of the SH0ES project (Supernovae and H0 for the Equation of State of dark energy) for Cepheid variable stars using the Hubble Space Telescope (HST) in 19 hosts of Type Ia supernovae (SNe Ia) and the maser-host galaxy NGC 4258. The targets include nine newly imaged SN Ia hosts using a novel strategy based on a long-pass filter that minimizes the number of HST orbits required to detect and accurately determine Cepheid properties. We carried out a homogeneous reduction and analysis of all observations, including new universal variability searches in all SN Ia hosts, which yielded a total of 2200 variables with well-defined selection criteria, the largest such sample identified outside the Local Group. These objects are used in a companion paper to determine the local value of H0 with a total uncertainty of 2.4%. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555. 11. CONNECTING GRBs AND ULIRGs: A SENSITIVE, UNBIASED SURVEY FOR RADIO EMISSION FROM GAMMA-RAY BURST HOST GALAXIES AT 0 < z < 2.5 Perley, D. A. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Perley, R. A. [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Hjorth, J.; Malesani, D. [Dark Cosmology Centre, Niels Bohr Institute, DK-2100 Copenhagen (Denmark); Michałowski, M. J. [Scottish Universities Physics Alliance, Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ (United Kingdom); Cenko, S. B. [NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavík (Iceland); Krühler, T. [European Southern Observatory, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago 19 (Chile); Levan, A. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Tanvir, N. R., E-mail: [email protected] [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom) 2015-03-10 Luminous infrared galaxies and submillimeter galaxies contribute significantly to stellar mass assembly and provide an important test of the connection between the gamma-ray burst (GRB) rate and that of overall cosmic star formation. We present sensitive 3 GHz radio observations using the Karl G. Jansky Very Large Array of 32 uniformly selected GRB host galaxies spanning a redshift range from 0 < z < 2.5, providing the first fully dust- and sample-unbiased measurement of the fraction of GRBs originating from the universe's most bolometrically luminous galaxies. Four galaxies are detected, with inferred radio star formation rates (SFRs) ranging between 50 and 300 M {sub ☉} yr{sup –1}. Three of the four detections correspond to events consistent with being optically obscured 'dark' bursts. Our overall detection fraction implies that between 9% and 23% of GRBs between 0.5 < z < 2.5 occur in galaxies with S {sub 3GHz} > 10 μJy, corresponding to SFR > 50 M {sub ☉} yr{sup –1} at z ∼ 1 or >250 M {sub ☉} yr{sup –1} at z ∼ 2. Similar galaxies contribute approximately 10%-30% of all cosmic star formation, so our results are consistent with a GRB rate that is not strongly biased with respect to the total SFR of a galaxy. However, all four radio-detected hosts have stellar masses significantly lower than IR/submillimeter-selected field galaxies of similar luminosities. We suggest that the GRB rate may be suppressed in metal-rich environments but independently enhanced in intense starbursts, producing a strong efficiency dependence on mass but little net dependence on bulk galaxy SFR. 12. The Metallicity and Dust Content of a Redshift 5 Gamma-Ray Burst Host Galaxy Sparre, M.; Hartoog, O.E.; Krühler, T.; Fynbo, J.P.U.; Watson, D.J.; Wiersema, K.; D'Elia, V.; Zafar, T.; Afonso, P.M.J.; Covino, S.; de Ugarte Postigo, A.; Flores, H.; Goldoni, P.; Greiner, J.; Hjorth, J.; Jakobsson, P.; Kaper, L.; Klose, S.; Levan, A.J.; Malesani, D.; Milvang-Jensen, B.; Nardini, M.; Piranomonte, S.; Sollerman, J.; Sánchez-Ramírez, R.; Schulze, S.; Tanvir, N.R.; Vergani, S.D.; Wijers, R.A.M.J. 2014-01-01 Observations of the afterglows of long gamma-ray bursts (GRBs) allow the study of star-forming galaxies across most of cosmic history. Here we present observations of GRB 111008A, from which we can measure metallicity, chemical abundance patterns, dust-to-metals ratio (DTM), and extinction of the GR 13. PS1-10bzj: A FAST, HYDROGEN-POOR SUPERLUMINOUS SUPERNOVA IN A METAL-POOR HOST GALAXY Lunnan, R.; Chornock, R.; Berger, E.; Milisavljevic, D.; Drout, M.; Sanders, N. E.; Challis, P. M.; Czekala, I.; Foley, R. J.; Fong, W.; Kirshner, R. P.; Leibler, C.; Marion, G. H.; Narayan, G. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Huber, M. E. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); McCrum, M.; Smartt, S. J. [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Rest, A. [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States); Roth, K. C. [Gemini Observatory, 670 N. Aohoku Place, Hilo, HI 96720 (United States); Scolnic, D., E-mail: [email protected] [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); and others 2013-07-10 We present observations and analysis of PS1-10bzj, a superluminous supernova (SLSN) discovered in the Pan-STARRS Medium Deep Survey at a redshift z = 0.650. Spectroscopically, PS1-10bzj is similar to the hydrogen-poor SLSNe 2005ap and SCP 06F6, though with a steeper rise and lower peak luminosity (M{sub bol} {approx_equal} -21.4 mag) than previous events. We construct a bolometric light curve, and show that while PS1-10bzj's energetics were less extreme than previous events, its luminosity still cannot be explained by radioactive nickel decay alone. We explore both a magnetar spin-down and circumstellar interaction scenario and find that either can fit the data. PS1-10bzj is located in the Extended Chandra Deep Field South and the host galaxy is imaged in a number of surveys, including with the Hubble Space Telescope. The host is a compact dwarf galaxy (M{sub B} Almost-Equal-To -18 mag, diameter {approx}< 800 pc), with a low stellar mass (M{sub *} Almost-Equal-To 2.4 Multiplication-Sign 10{sup 7} M{sub Sun }), young stellar population ({tau}{sub *} Almost-Equal-To 5 Myr), and a star formation rate of {approx}2-3 M{sub Sun} yr{sup -1}. The specific star formation rate is the highest seen in an SLSN host so far ({approx}100 Gyr{sup -1}). We detect the [O III] {lambda}4363 line, and find a low metallicity: 12 + (O/H) = 7.8 {+-} 0.2 ({approx_equal} 0.1 Z{sub Sun }). Together, this indicates that at least some of the progenitors of SLSNe come from young, low-metallicity populations. 14. NEAR-INFRARED IMAGING OF A z = 6.42 QUASAR HOST GALAXY WITH THE HUBBLE SPACE TELESCOPE WIDE FIELD CAMERA 3 Mechtley, M.; Windhorst, R. A.; Cohen, S. H.; Jansen, R. A.; Scannapieco, E. [School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287 (United States); Ryan, R. E.; Koekemoer, A. M. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Schneider, G.; Fan, X. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Hathi, N. P. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Keel, W. C. [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487 (United States); Roettgering, H. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA, Leiden (Netherlands); Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Strauss, M. A. [Princeton University Observatory, Princeton, NJ 08544 (United States); Yan, H. J. [Department of Physics and Astronomy, The University of Missouri, 701 South College Ave, Columbia, MO 65211 (United States) 2012-09-10 We report on deep near-infrared F125W (J) and F160W (H) Hubble Space Telescope Wide Field Camera 3 images of the z = 6.42 quasar J1148+5251 to attempt to detect rest-frame near-ultraviolet emission from the host galaxy. These observations included contemporaneous observations of a nearby star of similar near-infrared colors to measure temporal variations in the telescope and instrument point-spread function (PSF). We subtract the quasar point source using both this direct PSF and a model PSF. Using direct subtraction, we measure an upper limit for the quasar host galaxy of m{sub J} > 22.8 and m{sub H} > 23.0 AB mag (2 {sigma}). After subtracting our best model PSF, we measure a limiting surface brightness from 0.''3 to 0.''5 radius of {mu}{sub J} > 23.5 and {mu}{sub H} > 23.7 AB mag arcsec{sup -2} (2 {sigma}). We test the ability of the model subtraction method to recover the host galaxy flux by simulating host galaxies with varying integrated magnitude, effective radius, and Sersic index, and conducting the same analysis. These models indicate that the surface brightness limit ({mu}{sub J} > 23.5 AB mag arcsec{sup -2}) corresponds to an integrated upper limit of m{sub J} > 22-23 AB mag, consistent with the direct subtraction method. Combined with existing far-infrared observations, this gives an infrared excess log (IRX) > 1.0 and corresponding ultraviolet spectral slope {beta} > -1.2 {+-} 0.2. These values match those of most local luminous infrared galaxies, but are redder than those of almost all local star-forming galaxies and z {approx_equal} 6 Lyman break galaxies. 15. THE OPTICALLY UNBIASED GRB HOST (TOUGH) SURVEY. VI. RADIO OBSERVATIONS AT z {approx}< 1 AND CONSISTENCY WITH TYPICAL STAR-FORMING GALAXIES Michalowski, M. J.; Dunlop, J. S. [SUPA (Scottish Universities Physics Alliance), Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJ (United Kingdom); Kamble, A.; Kaplan, D. L. [Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 (United States); Hjorth, J.; Malesani, D.; Fynbo, J. P. U.; Kruehler, T. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Reinfrank, R. F. [CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); Bonavera, L. [Instituto de Fisica de Cantabria, CSIC-Universidad de Cantabria, Avda. de los Castros s/n, E-39005 Santander (Spain); Castro Ceron, J. M. [Department of Radio Astronomy, Madrid Deep Space Communications Complex (INTA-NASA/INSA), Ctra. M-531, km. 7, E-28.294 Robledo de Chavela (Madrid) (Spain); Ibar, E. [UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Garrett, M. A. [Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo (Netherlands); Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavik (Iceland); Levan, A. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Massardi, M. [INAF-Istituto di Radioastronomia, via Gobetti 101, I-40129 Bologna (Italy); Pal, S. [ICRAR, University of Western Australia, 35 Stirling Highway, Crawley, WA (Australia); Sollerman, J. [Oskar Klein Centre, Department of Astronomy, AlbaNova, Stockholm University, SE-10691 Stockholm (Sweden); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Van der Horst, A. J., E-mail: [email protected] [Astronomical Institute ' Anton Pannekoek' , University of Amsterdam, Science Park 904, 1098XH Amsterdam (Netherlands); and others 2012-08-20 The objective of this paper is to determine the level of obscured star formation activity and dust attenuation in a sample of gamma-ray burst (GRB) hosts, and to test the hypothesis that GRB hosts have properties consistent with those of the general star-forming galaxy populations. We present a radio continuum survey of all z < 1 GRB hosts in The Optically Unbiased GRB Host (TOUGH) sample supplemented with radio data for all (mostly pre-Swift) GRB-SN hosts discovered before 2006 October. We present new radio data for 22 objects and have obtained a detection for three of them (GRB 980425, 021211, 031203; none in the TOUGH sample), increasing the number of radio-detected GRB hosts from two to five. The star formation rate (SFR) for the GRB 021211 host of {approx}825 M{sub Sun} yr{sup -1}, the highest ever reported for a GRB host, places it in the category of ultraluminous infrared galaxies. We found that at least {approx}63% of GRB hosts have SFR < 100 M{sub Sun} yr{sup -1} and at most {approx}8% can have SFR > 500 M{sub Sun} yr{sup -1}. For the undetected hosts the mean radio flux (<35 {mu}Jy 3{sigma}) corresponds to an average SFR < 15 M{sub Sun} yr{sup -1}. Moreover, {approx}> 88% of the z {approx}< 1 GRB hosts have ultraviolet dust attenuation A{sub UV} < 6.7 mag (visual attenuation A{sub V} < 3 mag). Hence, we did not find evidence for large dust obscuration in a majority of GRB hosts. Finally, we found that the distributions of SFRs and A{sub UV} of GRB hosts are consistent with those of Lyman break galaxies, H{alpha} emitters at similar redshifts, and of galaxies from cosmological simulations. The similarity of the GRB population with other star-forming galaxies is consistent with the hypothesis that GRBs, a least at z {approx}< 1, trace a large fraction of all star formation, and are therefore less biased indicators than once thought. 16. On the Number of Galaxies at High Redshift Lorenzo Zaninetti 2015-09-01 Full Text Available The number of galaxies at a given flux as a function of the redshift, z, is derived when the z-distance relation is non-standard. In order to compare different models, the same formalism is also applied to the standard cosmology. The observed luminosity function for galaxies of the zCOSMOS catalog at different redshifts is modeled by a new luminosity function for galaxies, which is derived by the truncated beta probability density function. Three astronomical tests, which are the photometric maximum as a function of the redshift for a fixed flux, the mean value of the redshift for a fixed flux, and the luminosity function for galaxies as a function of the redshift, compare the theoretical values of the standard and non-standard model with the observed value. The tests are performed on the FORS Deep Field (FDF catalog up to redshift z = 1.5 and on the zCOSMOS catalog extending beyond z = 4. These three tests show minimal differences between the standard and the non-standard models. 17. Scaling relations between black holes and their host galaxies: comparing theoretical and observational measurements, and the impact of selection effects DeGraf, C.; Di Matteo, T.; Treu, T.; Feng, Y.; Woo, J.-H.; Park, D. 2015-11-01 We use the high-resolution simulation MassiveBlackII to examine scaling relations between black hole (BH) mass and host galaxy properties (σ, total M* and LV), finding good agreement with recent observational data, especially at the high-mass end. We find Gaussian intrinsic scatter (˜half the observed scatter) about all three relations, except among the most massive objects. Below z ˜ 2 the slope of the relations remain roughly z-independent, and only steepen by 50 per cent by z ˜ 4. The normalization of the σ, LV relations evolve by 0.3, 0.43 dex, while the M* correlation does not evolve out to at least z ˜ 2. Testing for selection biases, we find MBH- or M*-selected samples have steeper slopes than random samples, suggesting a constant-mass selection function can exhibit faster evolution than a random sample. We find a potential bias among high-LBH subsamples due to their more massive hosts, but that bright (active) active galactic nuclei exhibit no intrinsic bias relative to fainter (inactive) BHs in equivalent-mass hosts. Finally, we show that BHs below the local relation tend to grow faster than their host (72 per cent of BHs >0.3 dex below the mean relation have an MBH-M* trajectory steeper than the local relation), while those above have shallower trajectories (only 14 per cent are steeper than local). Thus BHs tend to grow faster than their hosts until surpassing the local relation, when their growth is suppressed, bringing them back towards the mean relation. 18. Spectroscopy of supernova host galaxies from the SDSS-II SN survey with the SDSS and BOSS spectrographs Olmstead, Matthew Dwaune Type Ia supernovae (SNeIa) have been used as standard candles to measure cosmological distances. The initial discovery of the accelerated expansion of the universe was performed using ~50 SNe Ia. Large SNe surveys have increased the number of spectroscopically-confirmed SNe Ia to over a thousand with redshift coverage beyond z = 1. We are now in the age of abundant photometry without the ability for full follow-up spectroscopy of all SN candidates. SN cosmology using these large samples will increasingly rely on robust photometric classification of SN candidates. Photometric classification will increase the sample by including faint SNe as these are preferentially not observed with follow-up spectroscopy. The primary concern with using photometrically classified SNe Ia in cosmology is when a core-collapse SNe is incorrectly classified as an SN Ia. This can be mitigated by obtaining the host galaxy redshift of each SN candidate and using this information as a prior in the photometric classification, removing one degree of freedom. To test the impact of redshift on photometric classification, I have performed an assessment on photometric classification of candidates from the Sloan Digital Sky Survey-II (SDSS-II) SN Survey. I have tested the classification with and without redshift priors by looking at the change of photometric classification, the effect of data quality on photometric classification, and the effect of SN light curve properties on photometric classification. Following our suggested classification scheme, there are a total of 1038 photometrically classified SNe Ia when using a flat redshift prior and 1002 SNe~Ia with the spectroscopic redshift. For 912 (91.0%) candidates classified as likely SNe Ia without redshift information, the classification is unchanged when adding the host galaxy redshift. Finally, I investigate the differences in the interpretation of the light curve properties with and without knowledge of the redshift. When using the SALT2 19. Identifying the Location in the Host Galaxy of Short GRB 1111l7A with the Chandra Sub- Arcsecond Position Sakamoto, Takanori; Troja, E.; Aoki, K.; Guiriec, S.; Im, M.; Leloudas, G.; Malesani, D.; Melandri, A.; deUgartePostigo, A.; Urata, Y.; Xu, D.; DAvanzo, P.; Gorosabel, J.; Anderson, M. I.; Fynbo, J. P. U.; Aoki, K.; Sanchez-Ramirez, R. 2012-01-01 We present our successful program using Chandra for identifying the X-ray afterglow with sub-arcsecond accuracy for the short GRB 111117A d iscovered by Swift and Fermi. Thanks to our rapid target of opportuni ty request, Chandra clearly detected the X-ray afterglow, whereas no optical afterglow was found in deep optical observations. Instead, we clearly detect the host galaxy in optica; and also in near-infrared b ands. We found that the best photometric redshift fitofthe host is z = 1.31:(+0.46/-0.23) (90% confidence), making it one of the highest redshift short GRBs. Furthermore, we see an offset of 1.0+/-O.2 arcseco nds, which corresponds to 8.4+/-1.7 kpc aSBuming z= 1.31, between the host and the afterglow position. We discuss the importance of using Chandra for obtaining sub-arcsecond localization of the afterglow in X -rays for short GRBs to study GRB environments in great detail. 20. The low-extinction afterglow in the solar-metallicity host galaxy of gamma-ray burst 110918A Elliott, J; Greiner, J; Savaglio, S; E., F Olivares; Rau, A; Postigo, A de Ugarte; Sánchez-Ramírez, R; Wiersema, K; Schady, P; Kann, D A; Filgas, R; Nardini, M; Berger, E; Fox, D; Gorosabel, J; Klose, S; Levan, A; Guelbenzu, A Nicuesa; Rossi, A; Schmidl, S; Sudilovsky, V; Tanvir, N R; Thöne, C C 2013-01-01 Metallicity is theoretically thought to be a fundamental driver in gamma-ray burst (GRB) explosions and energetics, but is still, even after more than a decade of extensive studies, not fully understood. This is largely related to two phenomena: a dust-extinction bias, that prevented high-mass and thus likely high-metallicity GRB hosts to be detected in the first place, and a lack of efficient instrumentation, that limited spectroscopic studies including metallicity measurements to the low-redshift end of the GRB host population. The subject of this work is the very energetic GRB 110918A, for which we measure a redshift of z=0.984. GRB 110918A gave rise to a luminous afterglow with an intrinsic spectral slope of b=0.70, which probed a sight-line with little extinction (A_V=0.16 mag) typical of the established distributions of afterglow properties. Photometric and spectroscopic follow-up observations of the galaxy hosting GRB 110918A, including optical/NIR photometry with GROND and spectroscopy with VLT/X-shoo... 1. Identifying the Location in the Host Galaxy of Short GRB 111117A with the Chandra Sub-arcsecond Position Sakamoto, T; Aoki, K; Guiriec, S; Im, M; Leloudas, G; Malesani, D; Melandri, A; Postigo, A de Ugarte; Urata, Y; Xu, D; D'Avanzo, P; Gorosabel, J; Jeon, Y; Sanchez-Ramirez, R; Andersen, M I; Bai, J; Barthelmy, S D; Briggs, M S; Foley, S; Fruchter, A S; Fynbo, J P U; Gehrels, N; Huang, K; Jang, M; Kawai, N; Korhonen, H; Mao, J; Norris, J P; Preece, R D; Racusin, J L; Thone, C C; Vida, K; Zhao, X 2012-01-01 We present our successful program using Chandra for identifying the X-ray afterglow with sub-arcsecond accuracy for the short GRB 111117A discovered by Swift and Fermi. Thanks to our rapid target of opportunity request, Chandra clearly detected the X-ray afterglow, whereas no optical afterglow was found in deep optical observations. Instead, we clearly detect the host galaxy in optical and also in near-infrared bands. We found that the best fit photometric redshift of the host is$z=1.31_{-0.23}^{+0.46}$(90% confidence), making it one of the highest redshift short GRBs. Furthermore, we see an offset of$1.0 \\pm 0.2$arcseconds, which corresponds to$8.4 \\pm 1.7$kpc assuming z=1.31, between the host and the afterglow position. We discuss the importance of using Chandra for obtaining sub-arcsecond localization of the afterglow in X-rays for short GRBs to study GRB environments in great detail. 2. Globular clusters as tracers of the host galaxy mass distribution: the Fornax dSph test case Arca-Sedda, Manuel 2016-01-01 The Fornax dwarf spheroidal galaxy is the most massive satellites of the Milky Way, claimed to be embedded in a huge dark matter halo, and the only among the Milky Way satellites hosting five globular clusters. Interestingly, their estimated masses, ages and positions seem hardly compatible with the presence of a significant dark matter component, as expected in the$\\Lambda$CDM scheme. Indeed, if Fornax would have a CDM halo with a standard density profile, all its globular clusters should have sunk to the galactic centre many Gyr ago due to dynamical friction. Due to this, some authors proposed that the most massive clusters may have formed out of Fornax and later tidally captured. In this paper we investigate the past evolution of the Fornax GC system by using both a recently developed, semi-analytical treatment of dynamical friction and direct$N$-body simulations of the orbital evolution of the globular clusters within Fornax and of Fornax galaxy around the Milky Way. Our results suggest that an "in-sit... 3. Massive stars formed in atomic hydrogen reservoirs: H i observations of gamma-ray burst host galaxies Michałowski, M. J.; Gentile, G.; Hjorth, J. 2015-01-01 , implying high levels of atomic hydrogen (HI), which suggests that the connection between atomic gas and star formation is stronger than previously thought. In this case, it is possible that star formation is directly fuelled by atomic gas (or that the H1-to-H2 conversion is very efficient, which rapidly...... exhaust molecular gas), as has been theoretically shown to be possible. This can happen in low-metallicity gas near the onset of star formation because cooling of gas (necessary for star formation) is faster than the H1-to-H2 conversion. Indeed, large atomic gas reservoirs, together with low molecular gas...... masses, stellar, and dust masses are consistent with GRB hosts being preferentially galaxies which have very recently started a star formation episode after accreting metal-poor gas from the intergalactic medium. This provides a natural route for forming GRBs in low-metallicity environments. The gas... 4. Structural Transition in the NGC 6251 Jet: an Interplay with the Supermassive Black Hole and Its Host Galaxy Tseng, Chih-Yin; Asada, Keiichi; Nakamura, Masanori; Pu, Hung-Yi; Algaba, Juan-Carlos; Lo, Wen-Ping 2016-12-01 The structure of the NGC 6251 jet on the milliarcsecond scale is investigated using images taken with the European VLBI Network and the Very Long Baseline Array. We detect a structural transition of the jet from a parabolic to a conical shape at a distance of (1-2) × 105 times the Schwarzschild radius from the central engine, which is close to the sphere of gravitational influence of the supermassive black hole (SMBH). We also examine the jet pressure profiles with the synchrotron minimum energy assumption to discuss the physical origin of the structural transition. The NGC 6251 jet, together with the M87 jet, suggests a fundamental process of structural transition in the jets of active galactic nuclei (AGNs). Collimated AGN jets are characterized by their external galactic medium, showing that AGN jets interplay with the SMBH and its host galaxy. 5. Structural Transition in the NGC 6251 Jet: An Interplay with the Supermassive Black Hole and Its Host Galaxy Tseng, Chih-Yin; Nakamura, Masanori; Pu, Hung-Yi; Algaba, Juan-Carlos; Lo, Wen-Ping 2016-01-01 The structure of the NGC 6251 jet at the milliarcsecond scale is investigated using the images taken with the European VLBI Network and the Very Long Baseline Array. We detect a structural transition of the jet from a parabolic to a conical shape at a distance of (1-2) x 10^5 times the Schwarzschild radius from the central engine, which is close to the sphere of gravitational influence (SGI) of the supermassive black hole (SMBH). We also examine the jet pressure profiles with the synchrotron minimum energy assumption to discuss the physical origin of the structural transition. The NGC 6251 jet, together with the M 87 jet, suggests a fundamental process of the structural transition in active galactic nuclei (AGN) jets. The collimated AGN jets are characterized by their external galactic medium, showing that AGN jets interplay with the SMBH and its host galaxy. 6. DETERMINING TYPE Ia SUPERNOVA HOST GALAXY EXTINCTION PROBABILITIES AND A STATISTICAL APPROACH TO ESTIMATING THE ABSORPTION-TO-REDDENING RATIO R{sub V} Cikota, Aleksandar [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching b. München (Germany); Deustua, Susana [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Marleau, Francine, E-mail: [email protected] [Institute for Astro- and Particle Physics, University of Innsbruck, Technikerstrasse 25/8, A-6020 Innsbruck (Austria) 2016-03-10 We investigate limits on the extinction values of Type Ia supernovae (SNe Ia) to statistically determine the most probable color excess, E(B – V), with galactocentric distance, and use these statistics to determine the absorption-to-reddening ratio, R{sub V}, for dust in the host galaxies. We determined pixel-based dust mass surface density maps for 59 galaxies from the Key Insight on Nearby Galaxies: a Far-infrared Survey with Herschel (KINGFISH). We use SN Ia spectral templates to develop a Monte Carlo simulation of color excess E(B – V) with R{sub V} = 3.1 and investigate the color excess probabilities E(B – V) with projected radial galaxy center distance. Additionally, we tested our model using observed spectra of SN 1989B, SN 2002bo, and SN 2006X, which occurred in three KINGFISH galaxies. Finally, we determined the most probable reddening for Sa–Sap, Sab–Sbp, Sbc–Scp, Scd–Sdm, S0, and irregular galaxy classes as a function of R/R{sub 25}. We find that the largest expected reddening probabilities are in Sab–Sb and Sbc–Sc galaxies, while S0 and irregular galaxies are very dust poor. We present a new approach for determining the absorption-to-reddening ratio R{sub V} using color excess probability functions and find values of R{sub V} = 2.71 ± 1.58 for 21 SNe Ia observed in Sab–Sbp galaxies, and R{sub V} = 1.70 ± 0.38, for 34 SNe Ia observed in Sbc–Scp galaxies. 7. Providing Stringent Star Formation Rate Limits of z ˜ 2 QSO Host Galaxies at High Angular Resolution Vayner, Andrey; Wright, Shelley A.; Do, Tuan; Larkin, James E.; Armus, Lee; Gallagher, S. C. 2016-04-01 We present integral field spectrograph (IFS) with laser guide star adaptive optics (LGS-AO) observations of z ˜ 2 quasi-stellar objects (QSOs) designed to resolve extended nebular line emission from the host galaxy. Our data was obtained with W. M. Keck and Gemini North Observatories, using OSIRIS and NIFS coupled with the LGS-AO systems, respectively. We have conducted a pilot survey of five QSOs, three observed with NIFS+AO and two observed with OSIRIS+AO at an average redshift of z = 2.2. We demonstrate that the combination of AO and IFSs provides the necessary spatial and spectral resolutions required to separate QSO emission from its host. We present our technique for generating a point-spread function (PSF) from the broad-line region of the QSO and performing PSF subtraction of the QSO emission to detect the host galaxy emission at a separation of ˜0.″2 (˜1.4 kpc). We detect Hα narrow-line emission for two sources, SDSS J1029+6510 (zHα = 2.182) and SDSS J0925+0655 (zHα = 2.197), that have evidence for both star formation and extended narrow-line emission. Assuming that the majority of narrow-line Hα emission is from star formation, we infer a star formation rate (SFR) for SDSS J1029+6510 of 78.4 M⊙ yr-1 originating from a compact region that is kinematically offset by 290-350 km s-1. For SDSS J0925+0655 we infer a SFR of 29 M⊙ yr-1 distributed over three clumps that are spatially offset by ˜7 kpc. The null detections on three of the QSOs are used to infer surface brightness limits and we find that at 1.4 kpc from the QSO the un-reddened star formation limit is ≲0.3 M⊙ yr-1 kpc-2. If we assume typical extinction values for z = 2 type-1 QSOs, the dereddened SFR for our null detections would be ≲0.6 M⊙ yr-1 kpc-2. These IFS observations indicate that while the central black hole is accreting mass at 10%-40% of the Eddington rate, if star formation is present in the host (1.4-20 kpc) it would have to occur diffusely with significant 8. The Lyα emission from high- z galaxies hosting strong damped Lyα systems Joshi, Ravi; Srianand, Raghunathan; Noterdaeme, Pasquier; Petitjean, Patrick 2017-02-01 We study the average Lyα emission associated with high-z strong (log N(H I) ≥ 21) damped Lyα systems (DLAs). We report Lyα luminosities (LLyα) for the full as well as various sub-samples based on N(H I), z, (r - i) colours of QSOs and rest equivalent width of Si IIλ1526 line (i.e. W1526). For the full sample, we find LLyα level detection of Lyα emission in the red part of the DLA trough. The LLyα is found to be higher for systems with higher W1526 with its peak, detected at ≥3σ, redshifted by about 300-400 km s-1 with respect to the systemic absorption redshift, as seen in Lyman break galaxies (LBGs) and Lyα emitters. A clear signature of a double-hump Lyα profile is seen when we consider W1526 ≥0.4 Å and (r - i) radiation that is 4-10 times stronger than the metagalactic UV background at these redshifts. The relationship between the SFR and surface mass density of atomic gas seen in DLAs is similar to that of local dwarf and metal-poor galaxies. We show that the low-luminosity galaxies will contribute appreciably to the stacked spectrum if the size-luminosity relation seen for H I at low z is also present at high-z. Alternatively, large Lyα haloes seen around LBGs could also explain our measurements. 9. A Monster At Any Other Epoch: Are Intermediate Redshift ULIRGs the Progenitors of QSO Host Galaxies? Rothberg, Barry; Fischer, Jackie; Rodrigues, Myriam; Pirzkal, Nor 2015-08-01 There is a clear progression from merger-induced SF to QSO activity via Ultraluminous Infrared Galaxies (ULIRGs). While not all mergers are ULIRGs, multi-wavelength imaging confirms that all local ULIRGs are mergers. At 0.4 1 are responsible for ˜ 70% of the co-moving IR density. At these earlier epochs ULIRGs contained more gas, formed stars faster, and their number density was much higher. At z>1 there are conflicting conclusions about ULIRGs. Many studies conclude they are massive star-forming galaxies, not major mergers nor AGN. Nearly all studies of ULIRGs at z > 0.4 have selected these systems via scaling observed 24μm or 170μm Spitzer fluxes to integrated 8-1000μm fluxes and inferring masses from scaling photometric fluxes or millimeter observations of CO gas emission. These methods often rely heavily on uncertain assumptions (e.g. gas conversions, SED fitting and templates). Instead, we have assembled a representative sample of "classically" selected ULIRGs (60 and 100μm IRAS fluxes and 12 and 25μm WISE fluxes) for 0.4 < z < 1.0 and obtained optical and near-IR imaging and spectroscopy from Hubble Space Telescope, Keck, and the Large Binocular Telescope. We use the same techniques for measuring the dynamical and BH masses of ULIRGs in the local Universe to measure these parameters in more distant systems. Unlike other methods, we directly measure the mass at an epoch when galaxy formation and evolution appears to have changed dramatically from what we see today and compare these intermediate redshift ULIRGs with their counterparts in the local Universe. Our restframe optical and UV spectroscopy also allow us to directly probe gas-metallicities, outflows, and measure the properties of their stellar populations. Our results indicate that these intermediate redshift ULIRGs are dynamically similar to their local counterparts. 10. Near-Infrared Imaging of a z=6.42 Quasar Host Galaxy With the Hubble Space Telescope Wide Field Camera 3 Mechtley, Matt; Ryan, Russell E; Schneider, Glenn; Cohen, Seth H; Jansen, Rolf A; Fan, Xiaohui; Hathi, Nimish P; Keel, William C; Koekemoer, Anton M; Röttgering, Huub; Scannapieco, Evan; Schneider, Donald P; Strauss, Michael A; Yan, Haojing 2012-01-01 We report on deep near-infrared F125W (J) and F160W (H) Hubble Space Telescope Wide Field Camera 3 images of the z=6.42 quasar J1148+5251 to attempt to detect rest-frame near-ultraviolet emission from the host galaxy. These observations included contemporaneous observations of a nearby star of similar near-infrared colors to measure temporal variations in the telescope and instrument point spread function (PSF). We subtract the quasar point source using both this direct PSF and a model PSF. Using direct subtraction, we measure an upper limit for the quasar host galaxy of m_J>22.8, m_H>23.0 AB mag (2 sigma). After subtracting our best model PSF, we measure a limiting surface brightness from 0.3"-0.5" radius of mu_J > 23.5, mu_H > 23.7 AB magarc (2 sigma). We test the ability of the model subtraction method to recover the host galaxy flux by simulating host galaxies with varying integrated magnitude, effective radius, and S\\'ersic index, and conducting the same analysis. These models indicate that the surface b... 11. Late-time VLA reobservations rule out ULIRG-like host galaxies for most pre- Swift long-duration gamma-ray bursts Perley, Daniel A.; Hjorth, Jens; Tanvir, Nial R.; Perley, Richard A. 2017-02-01 We present new Jansky Very Large Array observations of five pre-Swift gamma-ray bursts for which an ultraluminous [star formation rate (SFR) >100 M⊙ yr-1] dusty host galaxy had previously been inferred from radio or submillimetre observations taken within a few years after the burst. In four of the five cases, we no longer detect any source at the host location to limits much fainter than the original observations, ruling out the existence of an ultraluminous galaxy hosting any of these gamma-ray bursts (GRBs). We continue to detect a source at the position of GRB 980703, but it is much fainter than it was a decade ago and the inferred radio SFR (∼80 M⊙) is relatively modest. The radio flattening at 200-1000 d observed in the light curve of this GRB may have been caused by a decelerating counterjet oriented 180 deg away from the viewer, although an unjetted wind model can also explain the data. Our results eliminate all well-established ultraluminous infrared galaxies (ULIRGs) among the pre-Swift host population. They also rule out all cases for which an unobscured GRB was found in a galaxy dominated by heavily obscured star formation. When GRBs do occur in ULIRGs, the afterglow is almost always observed to be heavily obscured, consistent with the large dust opacities and high dust covering fractions characteristic of these systems. 12. A revised host galaxy association for GRB 020819B: a high-redshift dusty starburst, not a low-redshift gas-poor spiral Perley, Daniel A.; Krühler, Thomas; Schady, Patricia; Michałowski, Michał J.; Thöne, Christina C.; Petry, Dirk; Graham, John F.; Greiner, Jochen; Klose, Sylvio; Schulze, Steve; Kim, Sam 2017-02-01 The purported spiral host galaxy of GRB 020819B at z = 0.41 has been seminal in establishing our view of the diversity of long-duration gamma-ray burst environments: Optical spectroscopy of this host provided evidence that gamma-ray bursts (GRBs) can form even at high metallicities, whereas millimetric observations suggested that GRBs may preferentially form in regions with minimal molecular gas. We report new observations from the Very Large Telescope (Multi Unit Spectroscopic Explorer and X-shooter), which demonstrate that the purported host is an unrelated foreground galaxy. The probable radio afterglow is coincident with a compact, highly star forming, dusty galaxy at z = 1.9621. The revised redshift naturally explains the apparent non-detection of CO(3-2) line emission at the afterglow site from the Atacama Large Millimetre Observatory. There is no evidence that molecular gas properties in GRB host galaxies are unusual, and limited evidence that GRBs can form readily at a super-Solar metallicity. 13. The properties of the host galaxy and the immediate environment of GRB 980425 / SN 1998bw from the multi-wavelength spectral energy distribution MichaÅowski, MichaÅ J; Malesani, Daniele; MichaÅowski, Tadeusz; Cerón, José María Castro; Reinfrank, Robert F; Garrett, Michael A; Fynbo, Johan P U; Watson, Darach J; Jørgensen, Uffe G 2008-01-01 We present an analysis of the spectral energy distribution (SED) of the galaxy ESO 184-G82, the host of the closest known long gamma-ray burst (GRB) 980425 and its associated supernova SN 1998bw. We use our observations obtained at the Australia Telescope Compact Array (the third >3 sigma radio detection of a GRB host) as well as archival infrared (IR) and ultraviolet (UV) observations to estimate its star formation state. We find that ESO 184-G82 has a UV star formation rate (SFR) and stellar mass consistent with the population of cosmological GRB hosts and of local dwarf galaxies. It has however a higher specific SFR (per unit stellar mass) and lower molecular gas-to-dust ratio than luminous spiral galaxies. The mass of ESO 184-G82 is dominated by an older stellar population in contrast to the majority of GRB hosts. The Wolf-Rayet region ~800 pc from the supernova site experienced a starburst episode during which the majority of its stellar population was built up. Unlike that of the entire galaxy, its SED ... 14. Type Ia Supernova Properties as a Function of the Distance to the Host Galaxy in the SDSS-II SN Survey Galbany, Lluis [Institut de Fisica d' Altes Energies (IFAE), Barcelona (Spain); et al. 2012-08-20 We use type-Ia supernovae (SNe Ia) discovered by the SDSS-II SN Survey to search for dependencies between SN Ia properties and the projected distance to the host galaxy center, using the distance as a proxy for local galaxy properties (local star-formation rate, local metallicity, etc.). The sample consists of almost 200 spectroscopically or photometrically confirmed SNe Ia at redshifts below 0.25. The sample is split into two groups depending on the morphology of the host galaxy. We fit light-curves using both MLCS2k2 and SALT2, and determine color (AV, c) and light-curve shape (delta, x1) parameters for each SN Ia, as well as its residual in the Hubble diagram. We then correlate these parameters with both the physical and the normalized distances to the center of the host galaxy and look for trends in the mean values and scatters of these parameters with increasing distance. The most significant (at the 4-sigma level) finding is that the average fitted AV from MLCS2k2 and c from SALT2 decrease with the projected distance for SNe Ia in spiral galaxies. We also find indications that SNe in elliptical galaxies tend to have narrower light-curves if they explode at larger distances, although this may be due to selection effects in our sample. We do not find strong correlations between the residuals of the distance moduli with respect to the Hubble flow and the galactocentric distances, which indicates a limited correlation between SN magnitudes after standardization and local host metallicity. 15. The [OIII] emission line luminosity function of optically selected type-2 AGN from zCOSMOS Bongiorno, A; Zamorani, G; Lamareille, F; Lanzuisi, G; Miyaji, T; Bolzonella, M; Carollo, C M; Contini, T; Kneib, J P; Le Fèvre, O; Lilly, S J; Mainieri, V; Renzini, A; Scodeggio, M; Bardelli, S; Brusa, M; Caputi, K; Civano, F; Coppa, G; Cucciati, O; de la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Halliday, C; Hasinger, G; Koekemoer, A M; Iovino, A; Kampczyk, P; Knobel, C; Kovac, K; Le Borgne, J F; Le Brun, V; Maier, C; Merloni, A; Nair, P; Pello, R; Peng, Y; Montero, E Perez; Ricciardelli, E; Salvato, M; Silverman, J; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Zucca, E; Abbas, U; Bottini, D; Cappi, A; Cassata, P; Cimatti, A; Guzzo, L; Leauthaud, A; Maccagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Oesch, P; Porciani, C; Pozzetti, L; Scaramella, R 2009-01-01 We present a catalog of 213 type-2 AGN selected from the zCOSMOS survey. The selected sample covers a wide redshift range (0.15 16. ALMA Observations Show Major Mergers Among the Host Galaxies of Fast-growing, High-redshift Supermassive Black Holes Trakhtenbrot, Benny; Netzer, Hagai; Cicone, Claudia; Maiolino, Roberto; Shemmer, Ohad 2016-01-01 We present new ALMA band-7 data for a sample of six luminous quasars at z~4.8, powered by fast-growing supermassive black holes (SMBHs) with rather uniform properties: the typical accretion rates and black hole masses are L/L_Edd~0.7 and M_BH~10^9 M_sol. Our sample consists of three "FIR-bright" sources which were individually detected in previous Herschel/SPIRE observations, with star formation rates of SFR>1000 M_sol/yr, and three "FIR-faint" sources for which Herschel stacking analysis implies a typical SFR of ~400 M_sol/yr. The dusty interstellar medium in the hosts of all six quasars is clearly detected in the ALMA data, and resolved on scales of 2 kpc, in both continuum (\\lambda_rest~150um) and [CII]157.74um line emission. The continuum emission is in good agreement with the expectations from the Herschel data, confirming the intense SF activity in the quasars' hosts. Importantly, we detect companion sub-mm galaxies (SMGs) for three sources -- one FIR-bright and two FIR-faint, separated by ~14-45 kpc an... 17. EmpiriciSN: Re-sampling Observed Supernova/Host Galaxy Populations using an XD Gaussian Mixture Model Holoien, Thomas W -S; Wechsler, Risa H 2016-01-01 We describe two new open source tools written in Python for performing extreme deconvolution Gaussian mixture modeling (XDGMM) and using a conditioned model to re-sample observed supernova and host galaxy populations. XDGMM is new program for using Gaussian mixtures to do density estimation of noisy data using extreme deconvolution (XD) algorithms that has functionality not available in other XD tools. It allows the user to select between the AstroML (Vanderplas et al. 2012; Ivezic et al. 2015) and Bovy et al. (2011) fitting methods and is compatible with scikit-learn machine learning algorithms (Pedregosa et al. 2011). Most crucially, it allows the user to condition a model based on the known values of a subset of parameters. This gives the user the ability to produce a tool that can predict unknown parameters based on a model conditioned on known values of other parameters. EmpiriciSN is an example application of this functionality that can be used for fitting an XDGMM model to observed supernova/host datas... 18. Active Galactic Nuclei in Groups and Clusters of Galaxies: Detection and Host Morphology Arnold, Timothy J; Mulchaey, John S; Berti, Angela; Jeltema, Tesla E 2009-01-01 The incidence and properties of Active Galactic Nuclei (AGN) in the field, groups, and clusters can provide new information about how these objects are triggered and fueled, similar to how these environments have been employed to study galaxy evolution. We have obtained new XMM-Newton observations of seven X-ray selected groups and poor clusters with 0.02 10^{41}; M_R2.5}(L_X>10^{41}; M_R 19. Investigating the host galaxies of luminous AGN in the local universe with integral field spectroscopy McElroy, Rebecca; Croom, Scott; Husemann, Bernd; Close AGN Reference Survey; SAMI Galaxy Survey 2017-01-01 This thesis investigates how galaxies and their super massive black holes coevolve. We use integral field spectroscopy to search for evidence of AGN feedback and triggering. We demonstrate that outflows are ubiquitous among luminous local type 2 AGN using observations from the AAT's SPIRAL instrument. Using multiple component Gaussian emission line decomposition we are able to disentangle the kinematic and ionisation properties of these winds. This allows us to argue that the outflows from these AGN are directly impacting the surrounding ISM within the galaxies. We search for evidence of AGN triggering using data from The Close AGN Reference Survey (CARS). CARS aims to provide a detailed multi-wavelength view of 40 nearby (0.01 type not once, but twice. So called ‘changing look’ AGN are an uncommon phenomenon, but twice changed AGN are much rarer. This AGN first transitioned from a narrow line AGN (type 2) to a broad line AGN (type 1) in the 1980s. It was recently observed as part of CARS. Examination of the MUSE data for this particular source showed that it no longer had the spectral features typical of a type 1 AGN. The continuum emission from the accretion disk was no longer visible and the broad lines were dramatically diminished. In this talk we describe the possible reasons for this change, supported by analysis of multi-epoch optical photometry and spectroscopy, alongside data obtained through director’s discretionary time from Chandra, HST, and the VLA. We then conclude by discussing the implications of this discovery on our understanding of AGN timescales and the physics behind AGN spectral types. 20. GRB hosts through cosmic time - VLT/X-shooter emission-line spectroscopy of 96 GRB-selected galaxies at 0.1 < z < 3.6 Krühler, T; Fynbo, J P U; Hartoog, O E; Hjorth, J; Jakobsson, P; Perley, D A; Rossi, A; Schady, P; Schulze, S; Tanvir, N R; Vergani, S D; Wiersema, K; Afonso, P M J; Bolmer, J; Cano, Z; Covino, S; D'Elia, V; Postigo, A de Ugarte; Filgas, R; Friis, M; Graham, J F; Greiner, J; Goldoni, P; Gomboc, A; Hammer, F; Japelj, J; Kann, D A; Kaper, L; Klose, S; Levan, A J; Leloudas, G; Milvang-Jensen, B; Guelbenzu, A Nicuesa; Palazzi, E; Pian, E; Piranomonte, S; Sanchez-Ramirez, R; Savaglio, S; Selsing, J; Tagliaferri, G; Vreeswijk, P M; Watson, D J; Xu, D 2015-01-01 We present data and initial results from VLT/X-shooter emission-line spectroscopy of 96 GRB-selected galaxies at 0.1host spectroscopy available to date. The majority of our GRBs was detected by Swift and 76% are at 0.5hosts with redshift. The median SFR, for example, increases from ~0.6 M_sun/yr at z~0.6 up to ~15 M_sun/yr at z~2. A higher ratio of [OIII]/[OII] at higher redshifts leads to an increasing distance of GRB-selected galaxies to the locus of local galaxies in the BPT diagram. Oxygen abundances of the galaxies are distributed between 12+log(O/H)=7.9 and 12+log(O/H)=9.0 with a median of 12+log(O/H)~8.5. The fraction of GRB-selected galaxies with super-solar metallic... 1. The redshifted selected sample of long gamma-ray burst host galaxies: the complete metallicity measurements at$z \\leq 0.41$Niino, Yuu; Hashimoto, Tetsuya; Hattori, Takashi; Ishikawa, Shoto; Kashikawa, Nobunari; Kosugi, George; Onoue, Masafusa; Toshikawa, Jun; Yabe, Kiyoto 2016-01-01 We present the complete list of host galaxy metallicities for all long GRBs whose redshifts were determined to be$\\leq 0.41$before the end of March 2014, including newly obtained spectroscopic datasets of the host galaxies of GRB 060614, 090417B, and 130427A. We compare the metallicity distribution of the redshift selected complete sample to the model predictions, and constrain the relation between metallicity and GRB occurrence. We take account of spatial variation of metallicities among star forming regions within a galaxy. We found that the models, in which only low-metallicity stars produce GRBs with a sharp cutoff of GRB production efficiency around 12+log(O/H)$\\sim$8.2, can well reproduce the observed distribution, while the models with moderate (or no) metallicity dependence are not consitistent with the observations. This is the first fair estimate of the metallicity distribution of GRB host galaxies based on the redshift selected complete sample in the {\\it Swift} era. We also discuss possible sa... 2. Determining Type Ia Supernovae Host galaxy extinction probabilities and a statistical approach to estimating the absorption-to-reddening ratio$R_V$Cikota, Aleksandar; Marleau, Francine 2016-01-01 We investigate limits on the extinction values of Type Ia supernovae to statistically determine the most probable color excess, E(B-V), with galactocentric distance, and use these statistics to determine the absorption-to-reddening ratio,$R_V$, for dust in the host galaxies. We determined pixel-based dust mass surface density maps for 59 galaxies from the Key Insight on Nearby Galaxies: a Far-Infrared Survey with \\textit{Herschel} (KINGFISH, Kennicutt et al. (2011)). We use Type Ia supernova spectral templates (Hsiao et al. 2007) to develop a Monte Carlo simulation of color excess E(B-V) with$R_V$= 3.1 and investigate the color excess probabilities E(B-V) with projected radial galaxy center distance. Additionally, we tested our model using observed spectra of SN 1989B, SN 2002bo and SN 2006X, which occurred in three KINGFISH galaxies. Finally, we determined the most probable reddening for Sa-Sap, Sab-Sbp, Sbc-Scp, Scd-Sdm, S0 and Irregular galaxy classes as a function of$R/R_{25}$. We find that the larges... 3. Globular clusters as tracers of the host galaxy mass distribution: the Fornax dSph test case Arca-Sedda, M.; Capuzzo-Dolcetta, R. 2016-10-01 The Fornax dwarf spheroidal galaxy is the most massive satellites of the Milky Way, claimed to be embedded in a huge dark matter halo, and the only among the Milky Way satellites hosting five globular clusters. Interestingly, their estimated masses, ages and positions seem hardly compatible with the presence of a significant dark matter component, as expected in the ΛCDM scheme. Indeed, if Fornax would have a CDM halo with a standard density profile, all its globular clusters should have sunk to the galactic centre many Gyr ago due to dynamical friction. Due to this, some authors proposed that the most massive clusters may have formed out of Fornax and later tidally captured. In this paper, we investigate the past evolution of the Fornax GC system by using both a recently developed, semi-analytical treatment of dynamical friction and direct N-body simulations of the orbital evolution of the globular clusters within Fornax and of Fornax galaxy around the Milky Way. Our results suggest that an in situ' origin for all the clusters is likely if their observed positions are close to their spatial ones and their orbits are almost circular. Moreover, the Milky Way seems to accelerate the GC decay reducing the decay time of 15 per cent. Nevertheless, our results indicate that the GCs survival probability exceeds 50 per cent, even in the case of cuspy density profiles. We conclude that more detailed data are required to shed light on the Fornax dark matter content, to distinguish between a cuspy or a cored profile. 4. A Tidal Disruption Event in a Nearby Galaxy Hosting an Intermediate Mass Black Hole Donato, D; Cenko, S. B.; Covino, S.; Troja, E.; Pursimo, T.; Cheung, C. C.; Fox, O.; Kutyrev, A.; Campana, S.; Fugazza, D.; Landt, H.; Butler, N. R. 2014-01-01 We report the serendipitous discovery of a bright point source flare in the Abell cluster A1795 with archival EUVE and Chandra observations. Assuming the EUVE emission is associated with the Chandra source, the X-ray 0.5-7 kiloelectronvolt flux declined by a factor of approximately 2300 over a time span of 6 years, following a power-law decay with index approximately equal to 2.44 plus or minus 0.40. The Chandra data alone vary by a factor of approximately 20. The spectrum is well fit by a blackbody with a constant temperature of kiloteslas approximately equal to 0.09 kiloelectronvolts (approximately equal to 10 (sup 6) Kelvin). The flare is spatially coincident with the nuclear region of a faint, inactive galaxy with a photometric redshift consistent at the 1 sigma level with the cluster (redshift = 0.062476).We argue that these properties are indicative of a tidal disruption of a star by a black hole (BH) with log(M (sub BH) / M (sub 1 solar mass)) approximately equal to 5.5 plus or minus 0.5. If so, such a discovery indicates that tidal disruption flares may be used to probe BHs in the intermediate mass range, which are very difficult to study by other means. 5. Late-Time VLA Reobservations Rule Out ULIRG-Like Host Galaxies For Most Pre-Swift Long-Duration Gamma-Ray Bursts Perley, Daniel A; Tanvir, Nial R; Perley, Richard A 2016-01-01 We present new Jansky Very Large Array observations of five pre-Swift gamma-ray bursts for which an ultraluminous (SFR > 100 M_sun/yr) dusty host galaxy had previously been inferred from late-time radio or submillimetre observations taken 1-3 years after the burst. In four of the five cases we no longer detect any source at the host location to limits much fainter than the original observations, ruling out the existence of an ultraluminous galaxy hosting any of these GRBs. We continue to detect a source at the position of GRB 980703, but it is much fainter than it was a decade ago and the inferred radio star-formation rate (~80 M_sun) is relatively modest. The radio flattening at 200-1000 days observed in the light curve of this GRB may have been caused by a decelerating counterjet oriented 180 degrees away from the viewer, although an unjetted wind model can also explain the data. Our results eliminate all well-established pre-Swift ULIRG hosts, and all cases for which an unobscured GRB was found in a galaxy... 6. Keck Observations of the Young Metal-Poor Host Galaxy of the Super-Chandrasekhar-Mass Type Ia Supernova SN 2007if Childress, M; Aragon, C; Antilogus, P; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Chotard, N; Copin, Y; Fakhouri, H K; Gangler, E; Kerschhaggl, M; Kowalski, M; Hsiao, E Y; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Runge, K; Scalzo, R; Thomas, R C; Smadja, G; Tao, C; Weaver, B A; Wu, C 2011-01-01 We present Keck LRIS spectroscopy and$g$-band photometry of the metal-poor, low-luminosity host galaxy of the super-Chandrasekhar mass Type Ia supernova SN 2007if. Deep imaging of the host reveals its apparent magnitude to be$m_g=23.15\\pm0.06$, which at the spectroscopically-measured redshift of$z_{helio}=0.07450\\pm0.00015$corresponds to an absolute magnitude of$M_g=-14.45\\pm0.06$. Galaxy$g-r$color constrains the mass-to-light ratio, giving a host stellar mass estimate of$\\log(M_*/M_\\odot)=7.32\\pm0.17$. Balmer absorption in the stellar continuum, along with the strength of the 4000\\AA\\ break, constrain the age of the dominant starburst in the galaxy to be$t_\\mathrm{burst}=123^{+165}_{-77}$Myr, corresponding to a main-sequence turn-off mass of$M/M_\\odot=4.6^{+2.6}_{-1.4}$. Using the R$_{23}$method of calculating metallicity from the fluxes of strong emission lines, we determine the host oxygen abundance to be$12+\\log(O/H)_\\mathrm{KK04}=8.01\\pm0.09$, significantly lower than any previously reported... 7. Molecular Gas Kinematics and Star Formation Properties of the Strongly-lensed Quasar Host Galaxy RXS J1131–1231 Leung, T. K. Daisy; Riechers, Dominik A.; Pavesi, Riccardo 2017-02-01 We report observations of CO(J = 2 → 1) and {CO}(J=3\\to 2) line emission toward the quadruply-lensed quasar RXS J1131‑1231 at z = 0.654 obtained using the Plateau de Bure Interferometer (PdBI) and the Combined Array for Research in Millimeter-wave Astronomy (CARMA). Our lens modeling shows that the asymmetry in the double-horned CO(J = 2 → 1) line profile is mainly a result of differential lensing, where the magnification factor varies from ∼3 to ∼9 across different kinematic components. The intrinsically symmetric line profile and a smooth source-plane velocity gradient suggest that the host galaxy is an extended rotating disk, with a CO size of {R}{CO}∼ 6 kpc and a dynamical mass of {M}{dyn}∼ 8× {10}10 M ⊙. We also find a secondary CO-emitting source near RXS J1131‑1231, the location of which is consistent with the optically-faint companion reported in previous studies. The lensing-corrected molecular gas masses are M gas = (1.4 ± 0.3) × 1010 M ⊙ and (2.0 ± 0.1) × 109 M ⊙ for RXS J1131‑1231 and the companion, respectively. We find a lensing-corrected stellar mass of M * = (3 ± 1) × 1010 M ⊙ and a star formation rate of SFRFIR = (120 ± 63) M ⊙ yr‑1, corresponding to a specific SFR and star formation efficiency comparable to z ∼ 1 disk galaxies not hosting quasars. The implied gas mass fraction of ∼18 ± 4% is consistent with the previously observed cosmic decline since z ∼ 2. We thus find no evidence for quenching of star formation in RXS J1131‑1231. This agrees with our finding of an elevated {M}{BH}/{M}{bulge} ratio of >0.27{}-0.08+0.11% compared to the local value, suggesting that the bulk of its black hole mass is largely in place while its stellar bulge is still assembling. 8. Suppression of Star Formation in the Hosts of Low-Excitation Radio Galaxies Pace, Cameron 2015-01-01 The feedback from radio-loud active galactic nuclei (R-AGN) may help maintain low star formation (SF) rates in their early-type hosts, but the observational evidence for this mechanism has been inconclusive. We study systematic differences of aggregate spectral energy distributions (SEDs) of various subsets of$\\sim$4000 low-redshift R-AGN from Best & Heckman (2012) with respect to (currently) inactive control samples selected to have matching redshift, stellar mass, population age, axis ratio, and environment. Aggregate SEDs, ranging from the ultraviolet (UV) through mid-infrared (mid-IR, 22$\\mu$m), were constructed using a Bayesian method that eliminates biases from non-detections in GALEX and WISE. We study rare high-excitation sources separately from low-excitation ones, which we split by environment and host properties. We find that both the UV and mid-IR emission of non-cluster R-AGNs (80% of sample) are suppressed by$\\sim$0.2 dex relative to that of the control group, especially for moderately ma... 9. THE STELLAR, MOLECULAR GAS, AND DUST CONTENT OF THE HOST GALAXIES OF TWO z {approx} 2.8 DUST-OBSCURED QUASARS Lacy, M. [North American ALMA Science Center, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Petric, A. O. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Martinez-Sansigre, A. [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth, PO1 3FX (United Kingdom); Ridgway, S. E. [NOAO, Colina El Pino s/n, Casilla 603, La Serena (Chile); Sajina, A. [Tuffs University, Medford, MA 02155 (United States); Urrutia, T. [Spitzer Science Center, Caltech, Mail Code 220-6, Pasadena, CA 91125 (United States); Farrah, D. [Department of Physics and Astronomy, University of Sussex, Brighton, BN1 9RH (United Kingdom) 2011-12-15 We present optical through radio observations of the host galaxies of two dust-obscured, luminous quasars selected in the mid-infrared, at z = 2.62 and z = 2.99, including a search for CO emission. Our limits on the CO luminosities are consistent with these objects having masses of molecular gas {approx}< 10{sup 10} M{sub Sun }, several times less than those of luminous submillimeter-detected galaxies at comparable redshifts. Their near-infrared spectral energy distributions, however, imply that these galaxies have high stellar masses ({approx}10{sup 11}-10{sup 12} M{sub Sun }). The relatively small reservoirs of molecular gas and low dust masses are consistent with them being relatively mature systems at high-z. 10. PROVIDING STRINGENT STAR FORMATION RATE LIMITS OF z ∼ 2 QSO HOST GALAXIES AT HIGH ANGULAR RESOLUTION Vayner, Andrey; Wright, Shelley A. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON, M5S 3H4 (Canada); Do, Tuan [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON, M5S 3H4 (Canada); Larkin, James E. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Armus, Lee [Spitzer Science Center, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125 (United States); Gallagher, S. C. [Department of Physics and Astronomy, The University of Western Ontario, London, ON N6A 3K7 (Canada) 2016-04-10 We present integral field spectrograph (IFS) with laser guide star adaptive optics (LGS-AO) observations of z ∼ 2 quasi-stellar objects (QSOs) designed to resolve extended nebular line emission from the host galaxy. Our data was obtained with W. M. Keck and Gemini North Observatories, using OSIRIS and NIFS coupled with the LGS-AO systems, respectively. We have conducted a pilot survey of five QSOs, three observed with NIFS+AO and two observed with OSIRIS+AO at an average redshift of z = 2.2. We demonstrate that the combination of AO and IFSs provides the necessary spatial and spectral resolutions required to separate QSO emission from its host. We present our technique for generating a point-spread function (PSF) from the broad-line region of the QSO and performing PSF subtraction of the QSO emission to detect the host galaxy emission at a separation of ∼0.″2 (∼1.4 kpc). We detect Hα narrow-line emission for two sources, SDSS J1029+6510 (z{sub Hα} = 2.182) and SDSS J0925+0655 (z{sub Hα} = 2.197), that have evidence for both star formation and extended narrow-line emission. Assuming that the majority of narrow-line Hα emission is from star formation, we infer a star formation rate (SFR) for SDSS J1029+6510 of 78.4 M{sub ⊙} yr{sup −1} originating from a compact region that is kinematically offset by 290–350 km s{sup −1}. For SDSS J0925+0655 we infer a SFR of 29 M{sub ⊙} yr{sup −1} distributed over three clumps that are spatially offset by ∼7 kpc. The null detections on three of the QSOs are used to infer surface brightness limits and we find that at 1.4 kpc from the QSO the un-reddened star formation limit is ≲0.3 M{sub ⊙} yr{sup −1} kpc{sup −2}. If we assume typical extinction values for z = 2 type-1 QSOs, the dereddened SFR for our null detections would be ≲0.6 M{sub ⊙} yr{sup −1} kpc{sup −2}. These IFS observations indicate that while the central black hole is accreting mass at 10%–40% of the Eddington rate, if 11. The hydrogen-poor superluminous supernova iPTF13ajg and its host galaxy in absorption and emission Vreeswijk, Paul M; Gal-Yam, Avishay; De Cia, Annalisa; Quimby, Robert M; Sullivan, Mark; Cenko, S Bradley; Perley, Daniel A; Filippenko, Alexei V; Clubb, Kelsey I; Taddia, Francesco; Sollerman, Jesper; Leloudas, Giorgos; Arcavi, Iair; Rubin, Adam; Kasliwal, Mansi M; Cao, Yi; Yaron, Ofer; Tal, David; Ofek, Eran O; Capone, John; Kutyrev, Alexander S; Toy, Vicki; Nugent, Peter E; Laher, Russ; Surace, Jason; Kulkarni, Shrinivas R 2014-01-01 We present imaging and spectroscopy of a hydrogen-poor superluminous supernova (SLSN) discovered by the intermediate Palomar Transient Factory: iPTF13ajg. At a redshift of z=0.7403, derived from narrow absorption lines, iPTF13ajg peaked at an absolute magnitude M(u,AB)=-22.5, one of the most luminous supernovae to date. The uBgRiz light curves, obtained with the P48, P60, NOT, DCT, and Keck telescopes, and the nine-epoch spectral sequence secured with the Keck and the VLT (covering 3 rest-frame months), are tied together photometrically to provide an estimate of the flux evolution as a function of time and wavelength. The observed bolometric peak luminosity of iPTF13ajg is 3.2x10^44 erg/s, while the estimated total radiated energy is 1.3x10^51 erg. We detect narrow absorption lines of Mg I, Mg II, and Fe II, associated with the cold interstellar medium in the host galaxy, at two different epochs with X-shooter at the VLT. From Voigt-profile fitting, we derive the column densities log N(Mg I)=11.94+-0.06, log ... 12. AGN-Host Galaxy Connection: Morphology and Colours of X-ray Selected AGN at z < 2 Pović, M; García, A M Pérez; Bongiovanni, A; Cepa, J; Huertas-Company, M; Lara-López, M A; Lorenzo, M Fernández; Ederoclite, A; Alfaro, E; Castañeda, H; Gallego, J; González-Serrano, J I; González, J J 2012-01-01 The connection between AGN and their host galaxies has been widely studied over recent years, showing it to be of great importance for providing answers to some fundamental questions related with AGN fueling mechanisms, their formation and evolution. Using X-ray and one of the deepest broad-band optical data sets, we studied morphology and colours in relationship with X-ray properties for sources at redshifts z < 2.0, using a sample of 262 AGN in the Subaru/XMM-Newton Deep Survey (SXDS). Morphological classification was obtained using the galSVM code, one of the new methods useful especially when dealing with high-redshift sources and low-resolution data. Colour-magnitude diagrams were studied in relationship with redshift, morphology, X-ray obscuration, and X-ray-to-optical flux ratio. Finally, the significance of different regions was analysed on colour-magnitude diagrams, relating the observed properties of AGN populations with some models of their formation and evolution. 13. The bolometric output and host-galaxy properties of obscured AGN in the XMM-COSMOS survey Lusso, E; Vignali, C; Zamorani, G; Treister, E; Sanders, D; Bolzonella, M; Bongiorno, A; Brusa, M; Civano, F; Gilli, R; Mainieri, V; Nair, P; Aller, M C; Carollo, M; Koekemoer, A M; Merloni, A; Trump, J R 2011-01-01 We present a study of the multi-wavelength properties, from the mid-infrared to the hard X-rays, of a sample of 255 spectroscopically identified X-ray selected Type-2 AGN from the XMM-COSMOS survey. Most of them are obscured the X-ray absorbing column density is determined by either X-ray spectral analyses (for the 45% of the sample), or from hardness ratios. Spectral Energy Distributions (SEDs) are computed for all sources in the sample. The average SEDs in the optical band is dominated by the host-galaxy light, especially at low X-ray luminosities and redshifts. There is also a trend between X-ray and mid-infrared luminosity: the AGN contribution in the infrared is higher at higher X-ray luminosities. We calculate bolometric luminosities, bolometric corrections, stellar masses and star formation rates (SFRs) for these sources using a multi-component modeling to properly disentangle the emission associated to stellar light from that due to black hole accretion. For 90% of the sample we also have the morpholo... 14. VLT adaptive optics imaging of QSO host galaxies and close environment at z ~2.5: results from a pilot program Falomo, R; Scarpa, R; Treves, A 2004-01-01 We report ESO-VLT near-infrared adaptive optics imaging of one radio-loud (PKS 0113-283) and two radio-quiet (Q 0045-3337 and Q 0101-337) QSOs at z > 2. In the first case, we are able to resolve the QSO and find that it is hosted by an elliptical of absolute magnitude M(K) = -27.6. For the other two objects, no extended emission has been unambiguously detected. This result, though restricted to a single object, extends up to z ~2.5 the finding that cosmic evolution of radio-loud QSO hosts follows the trend expected for luminous and massive spheroids undergoing passive evolution. For Q 0045-3337, our high resolution images show that it is located 1.2 arcsec from a K = 17.5 foreground disc galaxy, which may act as a gravitational lens, since the QSO most probably lies within the galaxy Einstein radius. 15. Supplement: Going the Distance: Mapping Host Galaxies of LIGO and Virgo Sources in Three Dimensions Using Local Cosmography and Targeted Follow-up Singer, L P; Holz, D E; Farr, W M; Price, L R; Raymond, V; Cenko, S B; Gehrels, N; Cannizzo, J; Kasliwal, M M; Nissanke, S; Coughlin, M; Farr, B; Urban, Alex L; Vitale, S; Veitch, J; Graff, P; Berry, C P L; Mohapatra, S; Mandel, I 2016-01-01 This is an online supplement to https://arxiv.org/abs/1603.07333 . In the main Letter, we demonstrated a rapid algorithm for obtaining joint three-dimensional estimates of sky location and luminosity distance from observations of binary neutron star mergers with Advanced LIGO and Virgo. We argued that combining the reconstructed volumes with positions and redshifts of possible host galaxies can provide large-aperture but small field of view instruments with a manageable list of targets to search for optical or infrared emission. In this Supplement, we document the new HEALPix-based file format for 3D localizations of gravitational wave transients. We include Python sample code to show the reader how to perform simple manipulations of the 3D sky maps and extract ranked lists of likely host galaxies. Finally, we include mathematical details of the rapid volume reconstruction algorithm. 16. GRB hosts through cosmic time. VLT/X-Shooter emission-line spectroscopy of 96 γ-ray-burst-selected galaxies at 0.1 T. Krühler; D. Malesani; J.P.U. Fynbo; O.E. Hartoog; J. Hjorth; P. Jakobsson; D.A. Perley; A.. Rossi; P. Schady; S. Schulze; N.R. Tanvir; S.D. Vergani; K. Wiersema; P.M.J. Afonso; J. Bolmer; Z. Cano; S. Covino; V. D’Elia; A. de Ugarte Postigo; R. Filgas; M. Friis; J.F. Graham; J. Greiner; P. Goldoni; A. Gomboc; F. Hammer; J. Japelj; D.A. Kann; L. Kaper; S. Klose; A.J. Levan; G. Leloudas; B. Milvang-Jensen; A. Nicuesa Guelbenzu; E. Palazzi; E. Pian; S. Piranomonte; R. Sánchez-Ramírez; S. Savaglio; J. Selsing; G. Tagliaferri; P.M. Vreeswijk; D.J. Watson; D. Xu 2015-01-01 We present data and initial results from VLT/X-Shooter emission-line spectroscopy of 96 galaxies selected by long γ-ray bursts (GRBs) at 0.1 host spectra available to date. Most of our GRBs were detected by Swift and 76% are at 0.5 17. The host-galaxy response to the afterglow of GRB 100901A Hartoog, Olga E; Vreeswijk, Paul M; Kaper, Lex; Tanvir, Nial R; Savaglio, Sandra; Berger, Edo; Chornock, Ryan; Covino, Stefano; D'Elia, Valerio; Flores, Hector; Fynbo, Johan P U; Goldoni, Paolo; Gomboc, Andreja; Melandri, Andrea; Pozanenko, Alexei; Schaye, Joop; Postigo, Antonio de Ugarte; Wijers, Ralph A M J 2013-01-01 For Gamma-Ray Burst 100901A, we have obtained Gemini-North and Very Large Telescope optical afterglow spectra at four epochs: one hour, one day, three days and one week after the burst, thanks to the afterglow remaining unusually bright at late times. Apart from a wealth of metal resonance lines, we also detect lines arising from fine-structure levels of the ground state of Fe II, and from metastable levels of Fe II and Ni II at the host redshift (z = 1.4084). These lines are found to vary significantly in time. The combination of the data and modelling results shows that we detect the fall of the Ni II 4 F9/2 metastable level population, which to date has not been observed. Assuming that the population of the excited states is due to the UV-radiation of the afterglow, we estimate an absorber distance of a few hundred pc. This appears to be a typical value when compared to similar studies. We detect two intervening absorbers (z = 1.3147, 1.3179). Despite the wide temporal range of the data, we do not see sign... 18. Chandra X-ray and Hubble Space Telescope Imaging of Optically Selected Kiloparsec-Scale Binary Active Galactic Nuclei II: Host Galaxy Morphology and AGN Activity Shangguan, Jinyi; Ho, Luis C; Shen, Yue; Peng, Chien Y; Greene, Jenny E; Strauss, Michael A 2016-01-01 Binary active galactic nuclei (AGNs) provide clues to how gas-rich mergers trigger and fuel AGNs and how supermassive black hole (SMBH) pairs evolve in a gas-rich environment. While significant effort has been invested in their identification, the detailed properties of binary AGNs and their host galaxies are still poorly constrained. In a companion paper, we examined the nature of ionizing sources in the double nuclei of four kpc-scale binary AGNs with redshifts between 0.1~0.2. Here, we present their host galaxy morphology based on F336W (U-band) and F105W (Y-band) images taken by the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope. Our targets have double-peaked narrow emission lines and were confirmed to host binary AGNs with follow up observations. We find that kpc-scale binary AGNs occur in galaxy mergers with diverse morphological types. There are three major mergers with intermediate morphologies and a minor merger with a dominant disk component. We estimate the masses of the SMBHs from ... 19. The clustering of ALFALFA galaxies: dependence on HI mass, relationship to optical samples & clues on host halo properties Papastergis, Emmanouil; Haynes, Martha P; Rodríguez-Puebla, Aldo; Jones, Michael G 2013-01-01 We use a sample of ~6000 galaxies detected by the Arecibo Legacy Fast ALFA (ALFALFA) 21cm survey, to measure the clustering properties of HI-selected galaxies. We find no convincing evidence for a dependence of clustering on the galactic atomic hydrogen (HI) mass, over the range M_HI ~ 10^{8.5} - 10^{10.5} M_sun. We show that previously reported results of weaker clustering for low-HI mass galaxies are probably due to finite-volume effects. In addition, we compare the clustering of ALFALFA galaxies with optically selected samples drawn from the Sloan Digital Sky Survey (SDSS). We find that HI-selected galaxies cluster more weakly than even relatively optically faint galaxies, when no color selection is applied. Conversely, when SDSS galaxies are split based on their color, we find that the correlation function of blue optical galaxies is practically indistinguishable from that of HI-selected galaxies. At the same time, SDSS galaxies with red colors are found to cluster significantly more than HI-selected gala... 20. The 7 Ms Chandra Deep Field-South Survey: Cosmic Black-Hole Growth is Mainly Linked to Host-Galaxy Stellar Mass Brandt, W. Niel; Yang, Guang; Chen, Chien-Ting; Vito, Fabio 2017-08-01 The Chandra exposure on the Chandra Deep Field-South (CDF-S) has recently been increased to 7 Ms, allowing unmatched X-ray and multiwavelength characterization of cosmic black-hole growth in active galactic nuclei (AGNs). We have used these data to investigate the dependence of black-hole accretion rate (BHAR) on host-galaxy star formation rate (SFR) and stellar mass (M*) at z = 0.5-2. Our sample consists of 18,000 galaxies with SFR and M* measurements, and we use sample-mean BHAR for these galaxies to approximate their long-term average BHAR. Our sample-mean BHARs are derived from the CDF-S observations via both direct spectral analysis and stacking. The average BHAR is correlated positively with both SFR and M*, and the BHAR-SFR and BHAR-M* relations can both be described acceptably by linear models with a slope of unity. However, according to partial-correlation analyses, BHAR is correlated more strongly with M* than SFR. This result indicates that M* is the primary host-galaxy property related to black-hole growth, and the well-known BHAR-SFR relation is largely a secondary effect due to the "star-forming main sequence". Among our sources, massive galaxies have significantly higher BHAR/SFR ratios than less-massive galaxies, indicating the former have higher black-hole fueling efficiency and/or higher SMBH occupation fraction than the latter; e.g., the deeper potential wells in higher mass galaxies may promote black-hole accretion and counteract AGN/supernova feedback. Our results can naturally explain the observed proportionality between MBH and M* for local giant ellipticals, and suggest their MBH/M* ratios are higher than those of local star-forming galaxies. Finally, prospects for extending this work will be discussed; e.g., by further investigating the redshift evolution of the primary BHAR-M* relation and measuring this relation for even higher values of M*, above ~ 1011 solar masses, using wide-field X-ray surveys. 1. The bimodality of the 10k zCOSMOS-bright galaxies up to z ~ 1: a new statistical and portable classification based on the global optical galaxy properties Coppa, G; Zamorani, G; Bardelli, S; Bolzonella, M; Pozzetti, L; Vergani, D; Zucca, E; Cimatti, A; Lilly, S J; Carollo, C M; Contini, T; Le Fèvre, O; Renzini, A; Scodeggio, M; Mainieri, V; Bongiorno, A; Caputi, K; Cucciati, O; de la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Memeo, P; Iovino, A; Kampczyk, P; Kneib, J -P; Knobel, C; Koekemoer, A M; Kovac, K; Lamareille, F; Le Borgne, J F; Le Brun, V; Maier, C; Pellò, R; Peng, Y; Perez-Montero, E; Ricciardelli, E; Scarlata, C; Silverman, J D; Tanaka, M; Tasca, L; Tresse, L; Abbas, U; Bottini, D; Capak, P; Cappi, A; Cassata, P; Fumana, M; Guzzo, L; Leauthaud, A; Maccagni, D; Marinoni, C; Meneux, B; Oesch, P; Porciani, C; Scaramella, R; Scoville, N 2010-01-01 Our goal is to develop a new and reliable statistical method to classify galaxies from large surveys. We probe the reliability of the method by comparing it with a three-dimensional classification cube (Mignoli et al.~2009), using the same set of spectral, photometric and morphological parameters.We applied two different methods of classification to a sample of galaxies extracted from the zCOSMOS redshift survey, in the redshift range 0.5 0.5$, while galaxies with lower masses - of the order of $10^{10}$ Msun - are in transition at later epochs; galaxies with $M 5\\cdot 10^{10}$ Msun) mostly completed their transition before $z\\sim 1$.
2. The Compact, ∼1 kpc Host Galaxy of a Quasar at a Redshift of 7.1
Venemans, Bram P.; Walter, Fabian; Decarli, Roberto; Bañados, Eduardo; Hodge, Jacqueline; Hewett, Paul; McMahon, Richard G.; Mortlock, Daniel J.; Simpson, Chris
2017-03-01
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the [C ii] fine-structure line and the underlying far-infrared (FIR) dust continuum emission in J1120+0641, the most distant quasar currently known (z=7.1). We also present observations targeting the CO(2–1), CO(7–6), and [C i] 369 μm lines in the same source obtained at the Very Large Array and Plateau de Bure Interferometer. We find a [C ii] line flux of {F}[{{C}{{II}}]}=1.11+/- 0.10 Jy {km} {{{s}}}-1 and a continuum flux density of {S}227{GHz}=0.53+/- 0.04 mJy beam‑1, consistent with previous unresolved measurements. No other source is detected in continuum or [C ii] emission in the field covered by ALMA (∼ 25″). At the resolution of our ALMA observations (0.″23, or 1.2 kpc, a factor of ∼70 smaller beam area compared to previous measurements), we find that the majority of the emission is very compact: a high fraction (∼80%) of the total line and continuum flux is associated with a region 1–1.5 kpc in diameter. The remaining ∼20% of the emission is distributed over a larger area with radius ≲4 kpc. The [C ii] emission does not exhibit ordered motion on kiloparsec scales: applying the virial theorem yields an upper limit on the dynamical mass of the host galaxy of (4.3+/- 0.9)× {10}10 {M}ȯ , only ∼20 × higher than the central black hole (BH). The other targeted lines (CO(2–1), CO(7–6), and [C i]) are not detected, but the limits of the line ratios with respect to the [C ii] emission imply that the heating in the quasar host is dominated by star formation, and not by the accreting BH. The star formation rate (SFR) implied by the FIR continuum is 105–340 {M}ȯ {{yr}}-1, with a resulting SFR surface density of ∼100–350 {M}ȯ {{yr}}-1 kpc‑2, well below the value for Eddington-accretion-limited star formation.
3. SN 2010ay Is a Luminous and Broad-Lined Type Ic Supernova Within a Low-Metallicity Host Galaxy
Sanders, N. E.; Soderberg, A. M.; Valenti, S.; Foley, R. J.; Chornock, R.; Chomiuk, L.; Berger, E.; Smartt, S.; Hurley, K.; Barthelmy, S. D.; Levesque, E. M.; Narayan, G.; Botticella, M. T.; Briggs, M. S.; Connaughton, V.; Terada, Y.; Gehrels, N.; Golenetskii, S.; Mazets, E.; Cline, T.; von Kienlin, A.; Boynton, W.; Chambers, K. C.; Grav, T.; Heasley, J. N.
2012-01-01
We report on our serendipitous pre-discovery detection and follow-up observations of the broad-lined Type Ic supernova (SN Ic) 2010ay at z = 0.067 imaged by the Pan-STARRS1 3pi survey just approximately 4 days after explosion. The supernova (SN) had a peak luminosity, MR approx. -20.2 mag, significantly more luminous than known GRB-SNe and one of the most luminous SNe Ib/c ever discovered. The absorption velocity of SN 2010ay is v Si (is) approx. 19×10(exp 3) km s-1 at approximately 40 days after explosion, 2-5 times higher than other broad-lined SNe and similar to the GRB-SN 2010bh at comparable epochs. Moreover, the velocity declines approximately 2 times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of 56Ni, MNi = 0.9 solar mass. Applying scaling relations to the light curve, we estimate a total ejecta mass, Mej (is) approx. 4.7 solar mass, and total kinetic energy, EK (is) approx. 11 × 10(exp 51) erg. The ratio of MNi to Mej is approximately 2 times as large for SN 2010ay as typical GRB-SNe and may suggest an additional energy reservoir. The metallicity (log(O/H)PP04 + 12 = 8.19) of the explosion site within the host galaxy places SN 2010ay in the low-metallicity regime populated by GRB-SNe, and (is) approximately 0.5(0.2) dex lower than that typically measured for the host environments of normal (broad-lined) SNe Ic. We constrain any gamma-ray emission with E(gamma) (is) approximately less than 6 × 10(exp 48) erg (25-150 keV), and our deep radio follow-up observations with the Expanded Very Large Array rule out relativistic ejecta with energy E (is) approximately greater than 10(exp 48) erg. We therefore rule out the association of a relativistic outflow like those that accompanied SN 1998bw and traditional long-duration gamma-ray bursts (GRBs), but we place less-stringent constraints on a weak afterglow like that seen from XRF
4. ALMA Detection of the Vibrationally Excited HCN J=4-3 Emission Line in the AGN-Hosting Luminous Infrared Galaxy IRAS 20551-4250
Imanishi, Masatoshi
2013-01-01
We present results from our ALMA Cycle 0 observations, at the frequencies around the HCN, HCO+, and HNC J=4-3 transition lines, of the luminous infrared galaxy IRAS 20551-4250 at z=0.043, which is known to host an energetically important obscured AGN. In addition to the targeted HCN, HCO+, and HNC J=4-3 emission lines, two additional strong emission lines are seen, which we attribute to H2S and CH3CN(+CCH). The HCN-to-HCO+ J=4-3 flux ratio (~0.7) is higher than in the other starburst-dominated galaxy (~0.2) observed in our ALMA Cycle 0 program. We tentatively (~5 sigma) detected the vibrationally excited (v2=1) HCN J=4-3 (l=1f) emission line, which is important for testing an infrared radiative pumping scenario for HCN. This is the second detection of this molecular transition in external galaxies. The most likely reason for this detection is not only the high flux of this emission line, but also the small molecular line widths observed in this galaxy, suggesting that vibrational excitation of HCN may be rela...
5. Going the Distance: Mapping Host Galaxies of LIGO and Virgo Sources in Three Dimensions Using Local Cosmography and Targeted Follow-up
Singer, Leo P.; Chen, Hsin-Yu; Holz, Daniel E.; Farr, Will M.; Price, Larry R.; Raymond, Vivien; Cenko, S. Bradley; Gehrels, Neil; Cannizzo, John; Kasliwal, Mansi M.; Nissanke, Samaya; Coughlin, Michael; Farr, Ben; Urban, Alex L.; Vitale, Salvatore; Veitch, John; Graff, Philip; Berry, Christopher P. L.; Mohapatra, Satya; Mandel, Ilya
2016-09-01
The Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) discovered gravitational waves (GWs) from a binary black hole merger in 2015 September and may soon observe signals from neutron star mergers. There is considerable interest in searching for their faint and rapidly fading electromagnetic (EM) counterparts, though GW position uncertainties are as coarse as hundreds of square degrees. Because LIGO’s sensitivity to binary neutron stars is limited to the local universe, the area on the sky that must be searched could be reduced by weighting positions by mass, luminosity, or star formation in nearby galaxies. Since GW observations provide information about luminosity distance, combining the reconstructed volume with positions and redshifts of galaxies could reduce the area even more dramatically. A key missing ingredient has been a rapid GW parameter estimation algorithm that reconstructs the full distribution of sky location and distance. We demonstrate the first such algorithm, which takes under a minute, fast enough to enable immediate EM follow-up. By combining the three-dimensional posterior with a galaxy catalog, we can reduce the number of galaxies that could conceivably host the event by a factor of 1.4, the total exposure time for the Swift X-ray Telescope by a factor of 2, the total exposure time for a synoptic optical survey by a factor of 2, and the total exposure time for a narrow-field optical telescope by a factor of 3. This encourages us to suggest a new role for small field of view optical instruments in performing targeted searches of the most massive galaxies within the reconstructed volumes.
6. Gas dynamical imaging and dust properties of the strongly-lensed quasar host galaxy RXJ1131-1231 at z~0.65
Leung, Tsz Kuk Daisy; Riechers, Dominik; Pavesi, Riccardo
2017-01-01
Studies over the last two decades have revealed that the comoving star formation rate (SFR) and the black hole accretion rate densities have been steeply declining since z~2. Tracing the evolution of the cold molecular gas which fuels star formation and black hole accretion in galaxies at intermediate redshift (0.5github.com/astro313/uvmcmcfit), finding that the asymmetry in its double-horned line profile is a result of differential lensing, with a magnification factor varying from ˜3 to ˜9 across different kinematic components. We recover an intrinsically symmetric line profile and a source-plane velocity gradient that suggest the presence of an extended, ~6kpc radius gas disk with a dynamical mass of ˜8×1010M⊙, a gas mass of ~1.5×1010M⊙, and a gas mass fraction of ˜19% in RXJ1131-1231. The modest gas fraction is consistent with the observed trend of decreasing molecular gas content in star-forming galaxies since z˜2. Based on our spectral energy distribution (SED) modeling, we find a lensing-corrected stellar mass of ˜3×1010M⊙ and a SFR of ~120 M⊙ yr-1, a rate comparable to those of local mergers and high-z disk galaxies. The CO source size, gas depletion timescale and star formation efficiency of RXJ1131-1231 suggest that its star formation is driven by global gravitational instabilities rather than merger interactions. We also find a black hole-to-bulge mass ratio of >0.27%, which is higher than those of local galaxies, suggesting that its black hole mass is largely in place while its stellar bulge is still assembling. Our results thus support the emerging picture that quasars grow faster and/or earlier than their host galaxies at earlier epochs.
7. The zCOSMOS Redshift Survey: How group environment alters global downsizing trends
Iovino, A; Scodeggio, M; Knobel, C; Kovac, K; Lilly, S; Bolzonella, M; Tasca, L A M; Zamorani, G; Zucca, E; Caputi, K; Pozzetti, L; Oesch, P; Lamareille, F; Halliday, C; Bardelli, S; Finoguenov, A; Guzzo, L; Kampczyk, P; Maier, C; Tanaka, M; Vergani, D; Carollo, C M; Contini, T; Kneib, J -P; Le Fèvre, O; Mainieri, V; Renzini, A; Bongiorno, A; Coppa, G; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Le Borgne, J F; Le Brun, V; Mignoli, M; Pellò, R; Peng, Y; Pérez-Montero, E; Ricciardelli, E; Silverman, J D; Tresse, L; Abbas, U; Bottini, D; Cappi, A; Cassata, P; Cimatti, A; Koekemoer, A M; Leauthaud, A; MacCagni, D; Marinoni, C; McCracken, H J; Memeo, P; Meneux, B; Porciani, C; Scaramella, R; Schiminovich, D; Scoville, N
2009-01-01
We took advantage of the wealth of information provided by the first ~10000 galaxies of the zCOSMOS-bright survey and its group catalogue to study the complex interplay between group environment and galaxy properties. The classical indicator F_blue (fraction of blue galaxies) proved to be a simple but powerful diagnostic tool. We studied its variation for different luminosity and mass selected galaxy samples. Using rest-frame B-band selected samples, the groups galaxy population exhibits significant blueing as redshift increases, but maintains a lower F_blue with respect both to the global and the isolated galaxy population. However moving to mass selected samples it becomes apparent that such differences are largely due to the biased view imposed by the B-band luminosity selection, being driven by the population of lower mass, bright blue galaxies for which we miss the redder, equally low mass, counterparts. By focusing the analysis on narrow mass bins such that mass segregation becomes negligible we find th...
8. SN 2010ay IS A LUMINOUS AND BROAD-LINED TYPE Ic SUPERNOVA WITHIN A LOW-METALLICITY HOST GALAXY
Sanders, N. E.; Soderberg, A. M.; Foley, R. J.; Chornock, R.; Chomiuk, L.; Berger, E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Valenti, S.; Smartt, S.; Botticella, M. T. [Astrophysics Research Centre, School of Maths and Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Hurley, K. [Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States); Barthelmy, S. D.; Gehrels, N.; Cline, T. [NASA Goddard Space Flight Center, Code 661, Greenbelt, MD 20771 (United States); Levesque, E. M. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Narayan, G. [Department of Physics, Harvard University, Cambridge, MA 02138 (United States); Briggs, M. S.; Connaughton, V. [CSPAR, University of Alabama in Huntsville, Huntsville, AL (United States); Terada, Y. [Department of Physics, Saitama University, Shimo-Okubo, Sakura-ku, Saitama-shi, Saitama 338-8570 (Japan); Golenetskii, S.; Mazets, E., E-mail: [email protected] [Ioffe Physico-Technical Institute, Laboratory for Experimental Astrophysics, 26 Polytekhnicheskaya, St. Petersburg 194021 (Russian Federation); and others
2012-09-10
We report on our serendipitous pre-discovery detection and follow-up observations of the broad-lined Type Ic supernova (SN Ic) 2010ay at z = 0.067 imaged by the Pan-STARRS1 3{pi} survey just {approx}4 days after explosion. The supernova (SN) had a peak luminosity, M{sub R} Almost-Equal-To -20.2 mag, significantly more luminous than known GRB-SNe and one of the most luminous SNe Ib/c ever discovered. The absorption velocity of SN 2010ay is v{sub Si} Almost-Equal-To 19 Multiplication-Sign 10{sup 3} km s{sup -1} at {approx}40 days after explosion, 2-5 times higher than other broad-lined SNe and similar to the GRB-SN 2010bh at comparable epochs. Moreover, the velocity declines {approx}2 times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of {sup 56}Ni, M{sub Ni} = 0.9 M{sub Sun }. Applying scaling relations to the light curve, we estimate a total ejecta mass, M{sub ej} Almost-Equal-To 4.7 M{sub Sun }, and total kinetic energy, E{sub K} Almost-Equal-To 11 Multiplication-Sign 10{sup 51} erg. The ratio of M{sub Ni} to M{sub ej} is {approx}2 times as large for SN 2010ay as typical GRB-SNe and may suggest an additional energy reservoir. The metallicity (log (O/H){sub PP04} + 12 = 8.19) of the explosion site within the host galaxy places SN 2010ay in the low-metallicity regime populated by GRB-SNe, and {approx}0.5(0.2) dex lower than that typically measured for the host environments of normal (broad-lined) SNe Ic. We constrain any gamma-ray emission with E{sub {gamma}} {approx}< 6 Multiplication-Sign 10{sup 48} erg (25-150 keV), and our deep radio follow-up observations with the Expanded Very Large Array rule out relativistic ejecta with energy E {approx}> 10{sup 48} erg. We therefore rule out the association of a relativistic outflow like those that accompanied SN 1998bw and traditional long-duration gamma-ray bursts (GRBs), but we place less
9. Molecular Gas in Lensed z>2 Quasar Host Galaxies and the Star Formation Law for Galaxies with Luminous Active Galactic Nuclei
Riechers, Dominik A
2011-01-01
We report the detection of luminous CO(2-1), CO(3-2), and CO(4-3) emission in the strongly lensed high-redshift quasars B1938+666 (z=2.059), HE0230-2130 (z=2.166), HE1104-1805 (z=2.322), and B1359+154 (z=3.240), using the Combined Array for Research in Millimeter-wave Astronomy (CARMA). B1938+666 was identified in a `blind' CO redshift search, demonstrating the feasibility of such investigations with millimeter interferometers. These galaxies are lensing-amplified by factors of mu_L~11-170, and thus allow us to probe molecular gas in intrinsically fainter galaxies than currently possible without the aid of gravitational lensing. We report lensing-corrected intrinsic CO line luminosities of L'(CO) = 0.65-21 x 10^9 K km/s pc^2, translating to H2 masses of M(H2) = 0.52-1.7 x 10^9 (alpha_CO/0.8) M_sun. To investigate whether or not the AGN in luminous quasars substantially contribute to L_FIR, we study the L'(CO)-L_FIR relation for quasars relative to galaxies without a luminous AGN as a function of redshift. We ...
10. A Massive Molecular Gas Reservoir in the z=2.221 Type-2 Quasar Host Galaxy SMM J0939+8315 Lensed by the Radio Galaxy 3C220.3
Leung, T K Daisy
2016-01-01
We report the detection of CO(J=3-2) line emission in the strongly-lensed submillimeter galaxy (SMG) SMM J0939+8315 at z=2.221, using the Combined Array for Research in Millimeter-wave Astronomy. SMM J0939+8315 hosts a type-2 quasar, and is gravitationally lensed by the radio galaxy 3C220.3 and its companion galaxy at z=0.685. The 104 GHz continuum emission underlying the CO line is detected toward 3C220.3 with an integrated flux density of S_cont = 7.4 +/- 1.4 mJy. Using the CO(J=3-2) line intensity of I_(CO(3-2)) = (12.6 +/- 2.0) Jy km s^-1, we derive a lensing- and excitation-corrected CO line luminosity of L'(CO(3-2)) = (3.4 +/- 0.7) x 10^10 (10.1/mu_L) K km s^-1 pc^2 for the SMG, where mu_L is the lensing magnification factor inferred from our lens modeling. This translates to a molecular gas mass of M_gas = (2.7 +/- 0.6) x 10^10 (10.1/mu_L) Msun. Fitting spectral energy distribution models to the (sub)-millimeter data of this SMG yields a dust temperature of T = 63.1^{+1.1}_{-1.3} K, a dust mass of M_du...
11. Galaxy Formation
Sparre, Martin
galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof......-the-art cosmological simulation, Illustris, follow a tight relation between star formation rate and stellar mass. This relation agrees well with the observed relation at a redshift of z = 0 and z = 4, but at intermediate redshifts of z ' 2 the normalisation is lower than in real observations. This is highlighted...... of GRB host galaxies is affected by the fact that GRBs appear mainly to happen in low-metallicity galaxies. Solving this problem will make it possible to derive the total cosmic star formation rate more reliably from number counts of GRBs....
12. Mid-infrared properties of OH megamaser host galaxies. I: Spitzer IRS low- and high-resolution spectroscopy
Willett, Kyle W; Spoon, Henrik W W; Charmandaris, Vassilis; Armus, Lee
2011-01-01
We present mid-infrared spectra and photometry from the Infrared Spectrograph on the Spitzer Space Telescope for 51 OH megamasers (OHMs), along with 15 galaxies confirmed to have no megamaser emission above L_OH = 10^2.3 L_sun. The majority of galaxies display moderate-to-deep 9.7 um amorphous silicate absorption, with OHM galaxies showing stronger average absorption and steeper 20-30 um continuum emission than non-masing galaxies. Emission from multiple polycyclic aromatic hydrocarbons (PAHs), especially at 6.2, 7.7, and 11.3 um, is detected in almost all systems. Fine-structure atomic emission (including [Ne II], [Ne III], [S III], and [S IV]) and multiple H2 rotational transitions are observed in more than 90% of the sample. A subset of galaxies show emission from rarer atomic lines, such as [Ne V], [O IV], and [Fe II]. 50% of the OHMs show absorption from water ice and hydrogenated amorphous carbon grains (HACs), while absorption features from CO2, HCN, C2H2, and crystalline silicates are also seen in sev...
13. Multi-wavelength Observations of the Gas-rich Host Galaxy of PDS 456: a New Challenge for the ULIRG-to-QSO Transition Scenario
Yun, M S; Frayer, D T; Tilanus, R P J; Yun, Min S.
2004-01-01
We report new K-band, radio continuum, and CO (1-0) imaging observations and 850 micron photometric observations of PDS 456, the most luminous QSO in the local universe (z<0.3). The 0.6'' resolution K-band image obtained using the Keck telescope shows three compact K~16.5 (M(K)~ -21) sources at a projected distance of ~10 kpc to the southwest, and the host galaxy of PDS 456 may be interacting or merging with one or more companions. The observations using the OVRO millimeter array has revealed a narrow CO (1-0) line (FWHM = 181 km/s) centered at z=0.1849, and 9 x 10^9 solar mass of molecular gas mass is inferred. Radio continuum luminosity is nearly an order of magnitude larger than expected from its FIR luminosity, and the radio source, unresolved by the 2" beam of the VLA, is dominated by the AGN activity. Our 850 micron photometric observations suggest that the cold dust content of the host galaxy is less than one half of the amount in Arp 220. Its SED has both a QSO-like and a ULIRG-like nature, and the...
14. Hα Intensity Map of the Repeating Fast Radio Burst FRB 121102 Host Galaxy from Subaru/Kyoto 3DII AO-assisted Optical Integral-field Spectroscopy
Kokubo, Mitsuru; Mitsuda, Kazuma; Sugai, Hajime; Ozaki, Shinobu; Minowa, Yosuke; Hattori, Takashi; Hayano, Yutaka; Matsubayashi, Kazuya; Shimono, Atsushi; Sako, Shigeyuki; Doi, Mamoru
2017-08-01
We present the Hα intensity map of the host galaxy of the repeating fast radio burst FRB 121102 at a redshift of z = 0.193 obtained with the AO-assisted Kyoto 3DII optical integral-field unit mounted on the 8.2 m Subaru Telescope. We detected a compact Hα-emitting (i.e., star-forming) region in the galaxy, which has a much smaller angular size (GMOS z\\prime -band image (≃ 1\\buildrel{\\prime\\prime}\\over{.} 4 (4.6 kpc) at FWHM with ellipticity b/a=0.45). The spatial offset between the centroid of the Hα emission region and the position of the radio bursts is 0\\buildrel{\\prime\\prime}\\over{.} 08+/- 0\\buildrel{\\prime\\prime}\\over{.} 02 (0.26 ± 0.07 kpc), indicating that FRB 121102 is located within the star-forming region. This close spatial association of FRB 121102 with the star-forming region is consistent with expectations from young pulsar/magnetar models for FRB 121102, and it also suggests that the observed Hα emission region can make a major dispersion measure (DM) contribution to the host galaxy DM component of FRB 121102. Nevertheless, the largest possible value of the DM contribution from the Hα emission region inferred from our observations still requires a significant amount of ionized baryons in intergalactic medium (IGM; the so-called “missing” baryons) as the DM source of FRB 121102, and we obtain a 90% confidence level lower limit on the cosmic baryon density in the IGM in the low-redshift universe as {{{Ω }}}{IGM}> 0.012. Based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.
15. Host galaxies and environment of active galactic nuclei : a study of the XMM large scale structure survey
Tasse, Cyril
2008-01-01
Active galactic nuclei (AGN) result from the infall of matter onto the super-massive black holes that are situated at the centres of galaxies. This process releases an enormous amount of energy into the inter-stellar and inter-galactic medium. Hence, the study of AGN becomes essential in the context
16. Going the Distance: Mapping Host Galaxies of LIGO Sources in Three Dimensions Using Local Cosmography and Targeted Follow-up
Singer, L P; Holz, D E; Farr, W M; Price, L R; Raymond, V; Cenko, S B; Gehrels, N; Cannizzo, J; Kasliwal, M M; Nissanke, S; Coughlin, M; Farr, B; Urban, Alex L; Vitale, S; Veitch, J; Graff, P; Berry, C P L; Mohapatra, S; Mandel, I
2016-01-01
Advanced LIGO discovered gravitational waves from a binary black hole merger in September 2015 and may soon observe gravitational waves from neutron-star binary mergers. There is considerable interest in searching for their electromagnetic counterparts, though they are expected to be faint and fade rapidly and gravitational wave position uncertainties are as coarse as hundreds of square degrees. Since LIGO's sensitivity to binary neutron stars is limited to the local Universe, the area on the sky that must be searched could be reduced by weighting positions by mass, luminosity, or star formation in nearby galaxies. Since gravitational-wave observations provide information about luminosity distance, combining the reconstructed volume with sky positions and redshifts of galaxies could even more dramatically reduce the area to search. A key missing ingredient has been a rapid gravitational-wave parameter estimation algorithm that reconstructs the full distribution of sky location and distance. We demonstrate the...
17. The cosmic growth of the active black hole population at 1zCOSMOS, VVDS and SDSS
Schulze, A; Gavignaud, I; Schramm, M; Silverman, J; Merloni, A; Zamorani, G; Hirschmann, M; Mainieri, V; Wisotzki, L; Shankar, F; Fiore, F; Koekemoer, A M; Temporin, G
2014-01-01
We present a census of the active black hole population at 1zCOSMOS and SDSS), that cover a wide range of 3 dex in luminosity over our redshift interval of interest. We investigate the cosmic evolution of the AGN population as a function of AGN luminosity, black hole mass and accretion rate. Compared to z = 0 we find a distinct change in the shape of the BHMF and the ERDF, consistent with downsizing in black hole mass. The active fraction or duty cycle of type 1 AGN at z~1.5 is almost flat as...
18. High Resolution Simulations for Hierarchical Formation of Dark Matter Halos Hosting Galaxies and AGNs at High Redshift
Ishiyama, Tomoaki
2015-08-01
We present the evolution of dark matter halos in six large cosmological N-body simulations, called the ν2GC (New Numerical Galaxy Catalog) simulations on the basis of the LCDM cosmology consistent with observational results obtained by the Planck satellite. The largest simulation consists of 81923 (550 billion) dark matter particles in a box of 1.12h-1Gpc (a mass resolution of 2.20×108 h-1M⊙). Among simulations utilizing boxes larger than 1h-1Gpc, our simulation yields the highest resolution simulation that has ever been achieved. Compared with the Millennium simulation (Springel et al. 2005), our simulation offers the advantages of a mass resolution that is four times better and a spatial volume that is 11 times larger. A ν2GC simulation with the smallest box consists of eight billions particles in a box of 70h-1Mpc (a mass resolution of 3.44×106 -1M⊙). These simulations can follow the evolution of halos over masses of eight orders of magnitude, from small dwarf galaxies to massive clusters. Using the unprecedentedly high resolution and powerful statistics of the ν2GC simulations, we provide statistical results of the halo mass function, mass accretion rate, formation redshift, and merger statistics, and present accurate fitting functions for the Planck cosmology, from redshift 10 to 0. By combining the ν2GC simulations with our new semi-analytic galaxy formation model, we are able to prepare mock catalogs of galaxies and active galactic nuclei, which will be made publicly available in the near future.
19. Photometric Redshifts of Galaxies in COSMOS
Mobasher, B; Scoville, N Z; Dahlen, T; Salvato, M; Aussel, H; Thompson, D J; Feldmann, R; Tasca, L; Lefèvre, O; Lilly, S; Carollo, C M; Kartaltepe, J S; McCracken, H; Mould, J; Renzini, A; Sanders, D B; Shopbell, P L; Taniguchi, Y; Ajiki, M; Shioya, Y; Contini, T; Giavalisco, M; Ilbert, O; Iovino, A; Le Brun, V; Mainieri, V; Mignoli, M; Scodeggio, M
2006-01-01
We measure photometric redshifts and spectral types for galaxies in the COSMOS survey. We use template fitting technique combined with luminosity function priors and with the option to simultaneously estimate dust extinction (i.e. E(B-V)) for each galaxy.Our estimated redshifts are accurate to i<25 and z~1.2. Using simulations with sampling and noise characteristics similar to those in COSMOS, the accuracy and reliability is estimated for the photometric redshifts as a function of the magnitude limits of the sample, S/N ratios and the number of bands used. From the simulations we find that the ratio of derived 95% confidence interval in the redshift probability distribution to the estimated photometric redshift (D95) can be used to identify and exclude the catastrophic failures in the photometric redshift estimates. We compare the derived redshifts with high-reliability spectroscopic redshifts for a sample of 868 normal galaxies with z < 1.2 from zCOSMOS. Considering different scenarios, depending on us...
20. A tight relation between the age distributions of stellar clusters and the properties of the interstellar medium in the host galaxy
Miholics, Meghan; Kruijssen, J. M. Diederik; Sills, Alison
2017-09-01
The age distributions of stellar cluster populations have long been proposed to probe the recent formation history of the host galaxy. However, progress is hampered by the limited understanding of cluster disruption by evaporation and tidal shocks. We study the age distributions of clusters in smoothed particle hydrodynamics simulations of isolated disc galaxies, which include a self-consistent, physical model for the formation and dynamical evolution of the cluster population and account for the variation of cluster disruption in time and space. We show that the downward slope of the cluster age distribution due to disruption cannot be reproduced with a single functional form, because the disruption rate exhibits systematic trends with cluster age (the 'cruel cradle effect'). This problem is resolved by using the median cluster age to trace cluster disruption. Across 120 independent galaxy snapshots and simulated cluster populations, we perform two-dimensional power-law fits of the median cluster age to various macroscopic physical quantities and find that it scales as t_med∝ Σ ^{-0.51± 0.03}σ _1D^{-0.85± 0.10}M_min^γ, for the gas surface density Σ, gas velocity dispersion σ1D, and minimum cluster mass Mmin. This scaling accurately describes observed cluster populations and indicates disruption by impulsive tidal shocks from the interstellar medium. The term M_min^γ provides a model-independent way to measure the mass dependence of the cluster disruption time γ. Finally, the ensemble-average cluster lifetime depends on the gas density less strongly than the instantaneous disruption time of single clusters. These results reflect the variation of cluster disruption in time and space. We provide quantitative ways of accounting for these physics in cluster population studies.
1. A Ringed Dwarf LINER 1 Galaxy Hosting an Intermediate-mass Black Hole with Large-scale Rotation-like Hα Emission
Liu, Wen-Juan; Qian, Lei; Dong, Xiao-Bo; Jiang, Ning; Lira, Paulina; Cai, Zheng; Wang, Feige; Yang, Jinyi; Xiao, Ting; Kim, Minjin
2017-03-01
We report the discovery of a 20 kpc sized {{H}}α emission in SDSS J083803.68+540642.0, a ringed dwarf galaxy ({M}V=-17.89 mag) hosting an accreting intermediate-mass black hole at z = 0.02957. Analysis of the Hubble Space Telescope images indicates that it is an early-type galaxy with a featureless low-surface brightness disk ({μ }0=20.39 mag arcsec‑2 in the V band) and a prominent, relatively red bulge (V ‑ I = 2.03, {R}{{e}}=0.28 {kpc} or 0.″48) that accounts for ≈81% of the total light in the I band. A circumgalactic ring of a diameter 16 kpc is also detected, with a disperse shape on its south side. The optical emission lines reveal the nucleus to be a broad-line LINER. Our MMT longslit observation indicates that the kinematics of the extended {{H}}α emission is consistent with a rotational gaseous disk, with a mean blueshifted velocity of 162 {km} {{{s}}}-1 and mean redshifted velocity of 86 {km} {{{s}}}-1. According to our photoionization calculations, the large-scale {{H}}α emission is unlikely to be powered by the central nucleus or by hot evolved (post-AGB) stars interspersed in the old stellar populations, but by in situ star formation; this is vindicated by the line-ratio diagnostic of the extended emission. We propose that both the ring and large-scale {{H}}α -emitting gas are created by the tidal accretion in a collision—and then merger—with a gas-rich galaxy of a comparable mass.
2. Karl G. Jansky Very Large Array observations of cold dust and molecular gas in starbursting quasar host galaxies at z~4.5
Wagg, J; Aravena, M; Cox, P; Lentati, L; Maiolino, R; McMahon, R G; Riechers, D; Walter, F; Andreani, P; Hills, R; Wolfe, A
2014-01-01
We present Karl G. Jansky Very Large Array (VLA) observations of 44 GHz continuum and CO J=2-1 line emission in BR1202-0725 at z=4.7 (a starburst galaxy and quasar pair) and BRI1335-0417 at z=4.4 (also hosting a quasar). With the full 8 GHz bandwidth capabilities of the upgraded VLA, we study the (rest-frame) 250 GHz thermal dust continuum emission for the first time along with the cold molecular gas traced by the Low-J CO line emission. The measured CO J=2-1 line luminosities of BR1202-0725 are L'(CO) = (8.7+/-0.8)x10^10 K km/s pc^2 and L'(CO) = (6.0+/-0.5)x10^10 K km/s pc^2 for the submm galaxy (SMG) and quasar, which are equal to previous measurements of the CO J=5-4 line luminosities implying thermalized line emission and we estimate a combined cold molecular gas mass of ~9x10^10 Msun. In BRI1335-0417 we measure L'(CO) = (7.3+/-0.6)x10^10 K km/s pc^2. We detect continuum emission in the SMG BR1202-0725 North (S(44GHz) = 51+/-6 microJy), while the quasar is detected with S(44GHz) = 24+/-6 microJy and in BR...
3. A Massive Molecular Gas Reservoir in the Z = 2.221 Type-2 Quasar Host Galaxy SMM J0939+8315 Lensed by the Radio Galaxy 3C220.3
Leung, T. K. Daisy; Riechers, Dominik A.
2016-02-01
We report the detection of CO(J = 3 \\to 2) line emission in the strongly lensed submillimeter galaxy (SMG) SMM J0939+8315 at z = 2.221, using the Combined Array for Research in Millimeter-wave Astronomy. SMM J0939+8315 hosts a type-2 quasar, and is gravitationally lensed by the radio galaxy 3C220.3 and its companion galaxy at z = 0.685. The 104 GHz continuum emission underlying the CO line is detected toward 3C220.3 with an integrated flux density of Scont = 7.4 ± 1.4 mJy. Using the CO(J = 3 \\to 2) line intensity of ICO(3-2) = (12.6 ± 2.0) Jy km s-1, we derive a lensing- and excitation-corrected CO line luminosity of {L}{{CO(1-0)}}\\prime = (3.4 ± 0.7) × 1010 (10.1/μL) K km s-1 pc2 for the SMG, where μL is the lensing magnification factor inferred from our lens modeling. This translates to a molecular gas mass of Mgas = (2.7 ± 0.6) × 1010 (10.1/μL) M⊙. Fitting spectral energy distribution models to the (sub)-millimeter data of this SMG yields a dust temperature of T = 63.1{}-1.3+1.1 K, a dust mass of Mdust = (5.2 ± 2.1) × 108 (10.1/μL) M⊙, and a total infrared luminosity of LIR = (9.1 ± 1.2) ×1012 (10.1/μL) L⊙. We find that the properties of the interstellar medium of SMM J0939+8315 overlap with both SMGs and type-2 quasars. Hence, SMM J0939+8315 may be transitioning from a starbursting phase to an unobscured quasar phase as described by the “evolutionary link” model, according to which this system may represent an intermediate stage in the evolution of present-day galaxies at an earlier epoch.
4. Isolated Galaxies and Isolated Satellite Systems
Ann, H B; Choi, Yun-Young
2009-01-01
We search for isolated galaxies using a volume-limited sample of galaxies with 0.02r_{vir,nei} and \\rho <\\bar{\\rho} well segregates the CIG galaxies. We confirm the morphology conformity between the host and their satellites, which suggests importance of hydrodynamic interaction among galaxies within their virial radii in galaxy evolution.
5. Active galaxies in a complete sample of isolated galaxies
Sabater, J.; Leon, S.; Verdes-Montenegro, L.; Bergond, G.; Carpio, J.; Combes, F.; Espada, D.; Garc??a, E.; Huchtmeier, W.; Lisenfeld, Ute; Santander-Vela, J. D.; Sulentic, J.; Verley, S.
2006-01-01
Galaxy evolution depends strongly on the environment, in particular, galaxy-galaxy interaction can induce nuclear activity by removing angular momentum from the gas so feeding the central black hole. Hence a higher rate of nuclear activity is expected in interacting galaxies. Different studies of this topic lead to contradictory results. Some works conclude that galaxies hosting an active galactic nuclei (AGN) have a higher rate of companions than non active ones. On the other hand other stud...
6. The effects of assembly bias on cosmological inference from galaxy-galaxy lensing and galaxy clusters
McEwen, Joseph E
2016-01-01
The combination of galaxy-galaxy lensing (GGL) and galaxy clustering is a promising route to measuring the amplitude of matter clustering and testing modified gravity theories of cosmic acceleration. Halo occupation distribution (HOD) modeling can extend the approach down to nonlinear scales, but galaxy assembly bias could introduce systematic errors by causing the HOD to vary with large scale environment at fixed halo mass. We investigate this problem using the mock galaxy catalogs created by Hearin & Watson (2013, HW13), which exhibit significant assembly bias because galaxy luminosity is tied to halo peak circular velocity and galaxy colour is tied to halo formation time. The preferential placement of galaxies (especially red galaxies) in older halos affects the cutoff of the mean occupation function $\\langle N_\\text{cen}(M_\\text{min}) \\rangle$ for central galaxies, with halos in overdense regions more likely to host galaxies. The effect of assembly bias on the satellite galaxy HOD is minimal. We intro...
7. The Ly$\\alpha$ emission from high-$z$ galaxies hosting strong Damped Ly$\\alpha$ systems
Joshi, Ravi; Noterdaeme, Pasquier; Petitjean, Patrick
2016-01-01
We study the average Ly$\\alpha$ emission associated with high-$z$ strong (log $N$(H I) $\\ge$ 21) damped Ly$\\alpha$ systems (DLAs). We report Ly$\\alpha$ luminosities ($L_{\\rm Ly\\alpha}$) for the full as well as various sub-samples based on $N$(H I), $z$, $(r-i)$ colours of QSOs and rest equivalent width of Si II$\\lambda$1526 line (i.e., $W_{1526}$). For the full sample, we find $L_{\\rm Ly\\alpha}$$< 10^{41} (3\\sigma)\\ \\rm erg\\ s^{-1}$ with a $2.8\\sigma$ level detection of Ly$\\alpha$ emission in the red part of the DLA trough. The $L_{\\rm Ly\\alpha}$ is found to be higher for systems with higher $W_{1526}$ with its peak, detected at $\\geq 3\\sigma$, redshifted by about 300-400 $\\rm km\\ s^{-1}$ with respect to the systemic absorption redshift, as seen in Lyman Break Galaxies (LBGs) and Ly$\\alpha$ emitters. A clear signature of a double-hump Ly$\\alpha$ profile is seen when we consider $W_{1526} \\ge 0.4$ \\AA\\ and $(r-i) < 0.05$. Based on the known correlation between metallicity and $W_{1526}$, we interpret our...
8. The impact of the early stages of radio source evolution on the ISM of the host galaxies
Morganti, R; Oosterloo, T A; Holt, J; Tzioumis, A K; Wills, K
2002-01-01
The study of both neutral and ionized gas in young radio sources is providing key information on the effect the radio plasma has on the ISM of these objects. We present results obtained for the compact radio sources PKS1549-79, 4C12.50 and PKS1814-63 and for the intermediate-size radio galaxy 3C459. At least in the first two, low ionisation optical emission lines and HI absorption appear to be associated with the extended, but relatively quiescent, dusty cocoon surrounding the nucleus. The [OIII] lines are, on the other hand, mostly associated with the region of interaction between the radio plasma and the ISM, indicating a fast outflow from the canter. A case of fast outflow (up to ~1000 km/s) is also observed in HI in the radio source 4C12.50. As the radio source evolves, any obscuring material along the radio axis is swept aside until, eventually, cavities (of the same kind as observed e.g. in Cygnus A) are hollowed out on either side of the nucleus. We may witness this phase in the evolution of a radio so...
9. A Study of the Type II-Plateau Supernova 1999gi, and the Distance to its Host Galaxy, NGC 3184
Leonard, D C; Li, W; Matheson, T; Kirshner, R P; Chornock, R; Van Dyk, S D; Berlind, P; Calkins, M L; Challis, P M; Garnavich, P M; Jha, S; Mahdavi, A M; Leonard, Douglas C.; Filippenko, Alexei V.; Li, Weidong; Matheson, Thomas; Kirshner, Robert P.; Chornock, Ryan; Dyk, Schuyler D. Van; Berlind, Perry; Calkins, Michael L.; Challis, Peter M.; Garnavich, Peter M.; Jha, Saurabh; Mahdavi, Andisheh
2002-01-01
We present optical spectra and photometry sampling the first six months after discovery of supernova (SN) 1999gi in NGC 3184. SN 1999gi is shown to be a Type II-plateau event with a photometric plateau lasting until about 100 days after discovery. The reddening values resulting from five independent techniques are all consistent with an upper bound of E(B-V) < 0.45 mag established by comparing the early-time color of SN 1999gi with that of an infinitely hot blackbody, and yield a probable reddening of E(B-V) = 0.21 +/- 0.09 mag. Using the expanding photosphere method (EPM), we derive a distance to SN 1999gi of 11.1^{+2.0}_{-1.8} Mpc and an explosion date of 1999 December 5.8^{+3.0}_{-3.1}, or 4.1^{+3.0}_{-3.1} days prior to discovery. This distance is consistent with a recent Tully-Fisher distance derived to NGC 3184 (D ~ 11.59 Mpc), but is somewhat closer than the Cepheid distances derived to two galaxies that have generally been assumed to be members of a small group containing NGC 3184 (NGC 3319, D = 13...
10. Are LGRBs biased tracers of star formation? Clues from the host galaxies of the Swift/BAT6 complete sample of bright LGRBs. II: star formation rates and metallicities at z < 1
Japelj, J; Salvaterra, R; D'Avanzo, P; Mannucci, F; Fernandez-Soto, A; Boissier, S; Hunt, L K; Atek, H; Rodríguez-Muñoz, L; Scodeggio, M; Cristiani, S; Floc'h, E Le; Flores, H; Gallego, J; Ghirlanda, G; Gomboc, A; Hammer, F; Perley, D A; Pescalli, A; Petitjean, P; Puech, M; Rafelski, M; Tagliaferri, G
2016-01-01
Long gamma-ray bursts (LGRBs) are associated with the deaths of massive stars and could thus be a potentially powerful tool to trace cosmic star formation. However, especially at low redshifts (z < 1.5) LGRBs seem to prefer particular types of environment. Our aim is to study the host galaxies of a complete sample of bright LGRBs to investigate the impact of the environment on GRB formation. We study host galaxy spectra of the Swift/BAT6 complete sample of 14 z < 1 bright LGRBs. We use the detected nebular emission lines to measure the dust extinction, star formation rate (SFR) and nebular metallicity (Z) of the hosts and supplement the data set with previously measured stellar masses M$_{\\star}$. The distributions of the obtained properties and their interrelations (e.g. mass-metallicity and SFR-M$_{\\star}$ relations) are compared to samples of field star-forming galaxies.We find that LGRB hosts at z < 1 have on average lower SFRs than if they were direct star-formation tracers. By directly comparin...
11. The Host Galaxies of X-Ray Selected Active Galactic Nuclei to z - 2.5: Structure, Star-Formation and Their Relationships from CANDELS and Herschel/Pacs
Rosario, D.J.; McIntosh, D. H.; van der Wel, A.; Kartaltepe, J.; Lang, P.; Santini, P.; Wuyts, S.; Lutz, D.; Rafelski, M.; Villforth, C.; Alexander, D. M.; Bauer, F. E.; Bell, E. F.; Berta, S.; Brandt, W. N.; Conselice, C. J.; Dekel, A.; Faber, S. M.; Ferguson, H. C.; Genzel, R.; Grogin, N. A.; Kocevski, D. D.; Koekemoer, A. M.; Koo, D. C.; Straughn, A.
2014-01-01
We study the relationship between the structure and star-formation rate (SFR) of X-ray selected low and moderate luminosity active galactic nuclei (AGNs) in the two Chandra Deep Fields, using Hubble Space Telescope imaging from the Cosmic Assembly Near Infrared Extragalactic Legacy Survey (CANDELS) and deep far-infrared maps from the PEP+GOODS-Herschel survey. We derive detailed distributions of structural parameters and FIR luminosities from carefully constructed control samples of galaxies, which we then compare to those of the AGNs. At z is approximately 1, AGNs show slightly diskier light profiles than massive inactive (non-AGN) galaxies, as well as modestly higher levels of gross galaxy disturbance (as measured by visual signatures of interactions and clumpy structure). In contrast, at z 2, AGNs show similar levels of galaxy disturbance as inactive galaxies, but display a red central light enhancement, which may arise due to a more pronounced bulge in AGN hosts or due to extinguished nuclear light. We undertake a number of tests of both these alternatives, but our results do not strongly favour one interpretation over the other. The mean SFR and its distribution among AGNs and inactive galaxies are similar at z greater than 1.5. At z less than 1, however, clear and significant enhancements are seen in the SFRs of AGNs with bulge-dominated light profiles. These trends suggest an evolution in the relation between nuclear activity and host properties with redshift towards a minor role for mergers and interactions at z greater than 15
12. The KMOS AGN Survey at High redshift (KASHz): the prevalence and drivers of ionised outflows in the host galaxies of X-ray AGN
Harrison, C M; Mullaney, J R; Stott, J P; Swinbank, A M; Arumugam, V; Bauer, F E; Bower, R G; Bunker, A J; Sharples, R M
2015-01-01
We present the first results from the KMOS AGN Survey at High redshift (KASHz), a VLT/KMOS integral-field spectroscopic survey of z>0.6 AGN. We present galaxy-integrated spectra of 89 X-ray AGN (Lx=10^42-10^45 erg/s), for which we observed [O III] (z=1.1-1.7) or Halpha emission (z=0.6-1.1). The targets have X-ray luminosities representative of the parent AGN population and we explore the emission-line luminosities as a function of X-ray luminosity. For the [O III] targets, ~50 per cent have ionised gas velocities indicative of gas that is dominated by outflows and/or highly turbulent material (i.e., overall line-widths >~600 km/s). The most luminous half (i.e., Lx>6x10^43 erg/s) have a >~2 times higher incidence of such velocities. On the basis of our results, we find no evidence that X-ray obscured AGN are more likely to host extreme kinematics than unobscured AGN. Our KASHz sample has a distribution of gas velocities that is consistent with a luminosity-matched sample of z<0.4 AGN. This implies little ev...
13. Supplement: “Going the Distance: Mapping Host Galaxies of LIGO and Virgo Sources in Three Dimensions Using Local Cosmography and Targeted Follow-up” (2016, ApJL, 829, L15)
Singer, Leo P.; Chen, Hsin-Yu; Holz, Daniel E.; Farr, Will M.; Price, Larry R.; Raymond, Vivien; Cenko, S. Bradley; Gehrels, Neil; Cannizzo, John; Kasliwal, Mansi M.; Nissanke, Samaya; Coughlin, Michael; Farr, Ben; Urban, Alex L.; Vitale, Salvatore; Veitch, John; Graff, Philip; Berry, Christopher P. L.; Mohapatra, Satya; Mandel, Ilya
2016-09-01
This is a supplement to the Letter of Singer et al., in which we demonstrated a rapid algorithm for obtaining joint 3D estimates of sky location and luminosity distance from observations of binary neutron star mergers with Advanced LIGO and Virgo. We argued that combining the reconstructed volumes with positions and redshifts of possible host galaxies can provide large-aperture but small field of view instruments with a manageable list of targets to search for optical or infrared emission. In this Supplement, we document the new HEALPix-based file format for 3D localizations of gravitational-wave transients. We include Python sample code to show the reader how to perform simple manipulations of the 3D sky maps and extract ranked lists of likely host galaxies. Finally, we include mathematical details of the rapid volume reconstruction algorithm.
14. The host galaxies of X-ray selected Active Galactic Nuclei to z=2.5: Structure, star-formation and their relationships from CANDELS and Herschel/PACS
Rosario, D J; van der Wel, A; Kartaltepe, J; Lang, P; Santini, P; Wuyts, S; Lutz, D; Rafelski, M; Villforth, C; Alexander, D M; Bauer, F E; Bell, E F; Berta, S; Brandt, W N; Conselice, C J; Dekel, A; Faber, S M; Ferguson, H C; Genzel, R; Grogin, N A; Kocevski, D D; Koekemoer, A M; Koo, D C; Lotz, J M; Magnelli, B; Maiolino, R; Mozena, M; Mullaney, J R; Papovich, C J; Popesso, P; Tacconi, L J; Trump, J R; Avadhuta, S; Bassett, R; Bell, A; Bernyk, M; Bournaud, F; Cassata, P; Cheung, E; Croton, D; Donley, J; DeGroot, L; Guedes, J; Hathi, N; Herrington, J; Hilton, M; Lai, K; Lani, C; Martig, M; McGrath, E; Mutch, S; Mortlock, A; McPartland, C; O'Leary, E; Peth, M; Pillepich, A; Poole, G; Snyder, D; Straughn, A; Telford, O; Tonini, C; Wandro, P
2014-01-01
We study the relationship between the structure and star-formation rate (SFR) of X-ray selected low and moderate luminosity active galactic nuclei (AGNs) in the two Chandra Deep Fields, using Hubble Space Telescope imaging from the Cosmic Assembly Near Infrared Extragalactic Legacy Survey (CANDELS) and deep far-infrared maps from the PEP+GOODS-Herschel survey. We derive detailed distributions of structural parameters and FIR luminosities from carefully constructed control samples of galaxies, which we then compare to those of the AGNs. At z~1, AGNs show slightly diskier light profiles than massive inactive (non-AGN) galaxies, as well as modestly higher levels of gross galaxy disturbance (as measured by visual signatures of interactions and clumpy structure). In contrast, at z~2, AGNs show similar levels of galaxy disturbance as inactive galaxies, but display a red central light enhancement, which may arise due to a more pronounced bulge in AGN hosts or due to extinguished nuclear light. We undertake a number ...
15. Matching Supernovae to Galaxies
Kohler, Susanna
2016-12-01
One of the major challenges for modern supernova surveys is identifying the galaxy that hosted each explosion. Is there an accurate and efficient way to do this that avoids investing significant human resources?Why Identify Hosts?One problem in host galaxy identification. Here, the supernova lies between two galaxies but though the centroid of the galaxy on the right is closer in angular separation, this may be a distant background galaxy that is not actually near the supernova. [Gupta et al. 2016]Supernovae are a critical tool for making cosmological predictions that help us to understand our universe. But supernova cosmology relies on accurately identifying the properties of the supernovae including their redshifts. Since spectroscopic followup of supernova detections often isnt possible, we rely on observations of the supernova host galaxies to obtain redshifts.But how do we identify which galaxy hosted a supernova? This seems like a simple problem, but there are many complicating factors a seemingly nearby galaxy could be a distant background galaxy, for instance, or a supernovas host could be too faint to spot.The authors algorithm takes into account confusion, a measure of how likely the supernova is to be mismatched. In these illustrations of low (left) and high (right) confusion, the supernova is represented by a blue star, and the green circles represent possible host galaxies. [Gupta et al. 2016]Turning to AutomationBefore the era of large supernovae surveys, searching for host galaxies was done primarily by visual inspection. But current projects like the Dark Energy Surveys Supernova Program is finding supernovae by the thousands, and the upcoming Large Synoptic Survey Telescope will likely discover hundreds of thousands. Visual inspection will not be possible in the face of this volume of data so an accurate and efficient automated method is clearly needed!To this end, a team of scientists led by Ravi Gupta (Argonne National Laboratory) has recently
16. Do AGN suppress star formation in early-type galaxies?
Schawinski, Kevin
2010-01-01
The observation that AGN host galaxies preferentially inhabit the "green valley" between the blue cloud and the red sequence has significant consequences for our understanding of the co-evolution of galaxies and black holes via accretion events. I discuss the interpretation of green valley AGN host galaxy colours with particular focus on early-type galaxies.
17. Galaxy-galaxy Lensing: Dissipationless Simulations Versus the Halo Model
Mandelbaum, R; Seljak, U; Kravtsov, A V; Wechsler, R H; Mandelbaum, Rachel; Tasitsiomi, Argyro; Seljak, Uros; Kravtsov, Andrey V.; Wechsler, Risa H.
2004-01-01
Galaxy-galaxy lensing is a powerful probe of the relation between galaxies and dark matter halos, but its theoretical interpretation requires a careful modeling of various contributions, such as the contribution from central and satellite galaxies. For this purpose, a phenomenological approach based on the halo model has been developed, allowing for fast exploration of the parameter space of models. In this paper, we investigate the ability of the halo model to extract information from the g-g weak lensing signal by comparing it to high-resolution dissipationless simulations that resolve subhalos. We find that the halo model reliably determines parameters such as the host halo mass of central galaxies, the fraction of galaxies that are satellites, and their radial distribution inside larger halos. If there is a significant scatter present in the central galaxy host halo mass distribution, then the mean and median mass of that distribution can differ significantly from one another, and the halo model mass dete...
18. The Advanced Camera for Surveys General Catalog: A High Redshift Galaxy Morphology Catalog
Griffith, Roger; Newman, J.; Cooper, M.; Stern, D.; Moustakas, L.; Davis, M.
2009-05-01
We use publicly available data obtained with the Advanced Camera for Surveys (ACS) instrument on the Hubble Space Telescope to construct the ACS General Catalog (ACS-GC). The ACS-GC includes over 370,000 astronomical sources (stars + galaxies) derived from the AEGIS, COSMOS, GEMS, and GOODS surveys. We include publicly available redshifts from the DEEP2, COMBO-17, TKRS, PEARS and zCOSMOS surveys to supply redshifts for a considerable fraction ( 52%) of the imaging sample. GALAPAGOS was used to construct photometric (SExtractor) and morphological (GALFIT) catalogs. The morphological analysis assumes a single Sersic model for each object to derive quantitative structural parameters. Galaxy Zoo will measure visual morphologies for 200,000 of these galaxies. The ACS-GC includes color images, GALFIT residual images, a galaxy atlas, and a photometry + morphology + redshift catalog. We use these data to investigate the size-redshift relationship for both early and late-type galaxies out to z 1. The entire data set will be made publicly available through the NASA Extragalactic Database (NED) and LEVEL5.
19. Effect of bars on the galaxy properties
Vera, Matias; Alonso, Sol; Coldwell, Georgina
2016-10-01
Aims: With the aim of assessing the effects of bars on disk galaxy properties, we present an analysis of different characteristics of spiral galaxies with strong bars, weak bars and without bars. Methods: We identified barred galaxies from the Sloan Digital Sky Survey (SDSS). By visual inspection of SDSS images we classified the face-on spiral galaxies brighter than glog (M∗/M⊙) processing, reflected in the significant changes in the physical properties of the host galaxies.
20. How environment drives galaxy evolution: lessons learnt from satellite galaxies
Pasquali, A
2015-01-01
It is by now well established that galaxy evolution is driven by intrinsic and environmental processes, both contributing to shape the observed properties of galaxies. A number of early studies, both observational and theoretical, have shown that the star formation activity of galaxies depends on their environmental local density and also on galaxy hierarchy, i.e. centrals vs. satellites. In fact, contrary to their central (most massive) galaxy of a group/cluster, satellite galaxies are stripped of their gas and stars, and have their star formation quenched by their environment. Large galaxy surveys like SDSS now permit us to investigate in detail environment-driven transformation processes by comparing centrals and satellites. In this paper I summarize what we have so far learnt about environmental effects by analysing the observed properties of local central and satellite galaxies in SDSS, as a function of their stellar mass and the dark matter mass of their host group/cluster.
1. The very wide-field $gzK$ galaxy survey -- II. The relationship between star-forming galaxies at $z \\sim 2$ and their host haloes based upon HOD modelling
Ishikawa, Shogo; Hamana, Takashi; Toshikawa, Jun; Onoue, Masafusa
2016-01-01
We present the results of an halo occupation distribution (HOD) analysis of star-forming galaxies at $z \\sim 2$. We obtained high-quality angular correlation functions based on a large sgzK sample, which enabled us to carry out the HOD analysis. The mean halo mass and the HOD mass parameters are found to increase monotonically with increasing $K$-band magnitude, suggesting that more luminous galaxies reside i | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9001688361167908, "perplexity": 11531.573070797474}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257646176.6/warc/CC-MAIN-20180318204522-20180318224522-00464.warc.gz"} |
https://tex.stackexchange.com/questions/340492/can-cref-be-made-to-ignore-spaces | # Can \cref be made to ignore spaces?
I think this MWE says it all. \cite can ignore spaces in its argument, while \cref cannot. I wonder if \cref could be improved that way.
\documentclass{article}
\usepackage{cleveref}
\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@misc{1, author="One Author", year=2000}
@misc{2, author="Another Writer", year=2010}
\end{filecontents}
\begin{document}
We can use \cite{1,2} AND \cite{1, 2}!
Yet, we can use \cref{1,2}, but not \cref{1, 2}!
\section{Section 1}
\label{1}
\section{Section 2}
\label{2}
\bibliographystyle{apalike}
\bibliography{\jobname}
\end{document}
Why is this important? Because some text editors, TeXstudio being one of them, have trouble implementing line wraps at commas without a subsequent space.
• Is using LuaLaTeX an option for you?
– Mico
Nov 22 '16 at 20:36
• Related topic spaces in lists. Nov 22 '16 at 20:47
# Normalization with removal of spaces before and after label names and removing of empty entries.
The following example uses the comma parser of package kvsetkeys for parsing the label name list of the referencing commands of package cleveref. The internal \@cref with the list in its second argument is redefined for this:
\documentclass{article}
\usepackage{cleveref}
\usepackage{kvsetkeys}
\makeatletter
\let\org@@cref\@cref
\renewcommand*{\@cref}[2]{%
\begingroup
\toks@={}%
\edef\process@me{\endgroup
\noexpand\org@@cref{#1}{\the\toks@}%
}\process@me
}
\expandafter\ifx\expandafter\\\the\toks@\\%
\toks@{#1}%
\else
\toks@\expandafter{\the\toks@,#1}%
\fi
}
\makeatother
\begin{document}
\noindent
We can use \cref{1,2}, and now \cref{1, 2},\\
and even with a leading or trailing comma: \Cref{ , 1 , 2 ,}.
\section{Section 1}
\label{1}
\section{Section 2}
\label{2}
\end{document}
# Removal of open spaces and retaining commas
Solution that zaps all open spaces. If a label contains spaces, the label must be put in curly braces.:
\documentclass{article}
\usepackage{cleveref}
\usepackage{kvsetkeys}
\makeatletter
\let\org@@cref\@cref
\renewcommand*{\@cref}[2]{%
\edef\process@me{%
\noexpand\org@@cref{#1}{\zap@space#2 \@empty}%
}\process@me
}
\makeatother
\begin{document}
\noindent
We can use \cref{1,2}, and now \cref{1, 2}.
\section{Section 1}
\label{1}
\section{Section 2}
\label{2}
\end{document}
\zap@space is defined in the LaTeX kernel and is used to normalize options list for classes and packages, for example.
• This answer has one drawback: \cref{1,2,3,,4} (sections 1-3 and 4) shall behave differently from \cref{1,2,3,4} (sections 1-4). This behavior is documented in cleveref, yet lost with this solution.
– bers
Nov 22 '16 at 20:54
• @bers See updated answer. Nov 22 '16 at 21:01
• Thanks. Your second example does not even need \usepackage{kvsetkeys}.
– bers
Nov 25 '16 at 4:19
Almost self-explaining code:
\begin{filecontents}{\jobname.bib}
@misc{1, author="One Author", year=2000}
@misc{2, author="Another Writer", year=2010}
\end{filecontents}
\documentclass{article}
\usepackage{xparse}
\usepackage{cleveref}
\ExplSyntaxOn
\cs_set_eq:Nc \bers_cref:nn { @cref }
\cs_generate_variant:Nn \bers_cref:nn { nx }
\cs_set_protected:cpn { @cref } #1 #2
{
\seq_set_split:Nnn \l_bers_cref_seq { , } { #2 }
\bers_cref:nx { #1 } { \seq_use:Nn \l_bers_cref_seq { , } }
}
\seq_new:N \l_bers_cref_seq
\ExplSyntaxOff
\begin{document}
We can use \cite{1,2} AND \cite{1, 2}!
Yet, we can use \cref{1 space,2}, but also \cref{1 space, 2}!
Also \cref{1 space,2 , 3,, 4}
Also \Cref{1 space, 2, 3 , , 4}
\section{Section 1}
\label{1 space}
\section{Section 2}
\label{2}
\section{Section 3}
\label{3}
\section{Section 4}
\label{4}
\bibliographystyle{apalike}
\bibliography{\jobname}
\end{document}
I redefine the internal command \@cref to first split its second argument at commas, which removes leading and trailing spaces, but preserves inner ones. The original \@cref is saved in \bers_cref:nn, and then \@cref is redefined to use \bers_cref:nx, a variant that fully expands its second argument where we do \seq_use:Nn with a comma between entries.
Note that also \Cref is modified automatically. Empty entries are honored.
Here's a LuaLaTeX-based solution. It allows whitespace (spaces, tab characters, line breaks) in the arguments of \cref, \Cref, and \labelcref. Note that the approach pursued in this solution doesn't modify the cleveref macros in any way.
\documentclass{article}
\usepackage{cleveref}
\usepackage{luacode}
\begin{luacode}
function nospace ( t ) -- remove all whitespace characters from string "t"
return ( t:gsub ( "%s", "" ) )
end
function crefnospace ( s )
return ( s:gsub ( "\\.-[cC]ref%s-%b{}" , nospace ) )
end
\end{luacode}
\labelcref{ b , {a }}'' works too. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.836695671081543, "perplexity": 15451.717272437361}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964362952.24/warc/CC-MAIN-20211204063651-20211204093651-00477.warc.gz"} |
http://math.stackexchange.com/questions/275855/explanation-of-two-integral-equations-and-implementation | # Explanation of two integral equations and implementation
I have a problem with these two equations showing in the pictures.
Equation 1:
Equation 2:
1.I have two vectors represented the C(m) and S(m) in the two equations. I am trying to implement these equations in Matlab. Instead of doing a continuous integral operation, I think I should do the summation. For example, the first equation
A1 = sqrt(sum(C.^2));
Am I right? Also, I am not sure how to implement equation two that contains a ||dM||. Please help.
2.What are the mathematical meaning of these two equations? I think the first one may related to the 'sum of squares', if C(m) is a vector then this equation will measure the total variance of the random variable in vector C or some kind of average of vector C? What about the second one?
Thanks very much for your help! A.
- | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.959368884563446, "perplexity": 416.111089030614}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-18/segments/1461860117783.16/warc/CC-MAIN-20160428161517-00023-ip-10-239-7-51.ec2.internal.warc.gz"} |
http://mathhelpforum.com/advanced-algebra/68170-order-group.html | # Math Help - order of the group
1. ## order of the group
Let G be a group and x belongs to G,
Define ord(x) = min{r >= 1 : x^r = 1}
If f: G map to H is an injective group homomorphism. Show that, for
each x in G, ord(f(x)) = ord(x).
I think I come up with the approach is that , I need to show that
ord(f(x)) divides r and hence the result is proved.
Or: I can somehow show that ord(f(x)) = min{ r >= 1 : (f(x))^r = 1} which is by the definition.
Can you tell me whether the above approaches are right or wrong, if they are wrong then show me how to solve this question please?
2. Originally Posted by knguyen2005
Let G be a group and x belongs to G,
Define ord(x) = min{r >= 1 : x^r = 1}
If f: G map to H is an injective group homomorphism. Show that, for
each x in G, ord(f(x)) = ord(x).
I think I come up with the approach is that , I need to show that
ord(f(x)) divides r and hence the result is proved.
Or: I can somehow show that ord(f(x)) = min{ r >= 1 : (f(x))^r = 1} which is by the definition.
Can you tell me whether the above approaches are right or wrong, if they are wrong then show me how to solve this question please?
Let $\phi: G\to H$ be an injective homomorphism.
And let $x\in G$ (assuming it has finite order) have order $k$.
Thus, $x^k = e$ but then $\phi(x)^k = \phi(x^k) = e'$.
Say that there is $j with $\phi^(x)^j = e'$ but then $\phi (x^j) = e' \implies x^j = e$.
But this is contradition because $j and so $k$ is order of $\phi(x)$.
3. [Thus, $x^k = e$ but then $\phi(x)^k = \phi(x^k) = e'$.
Say that there is $j with $\phi^(x)^j = e'$ but then $\phi (x^j) = e' \implies x^j = e$.
I am not sure I understand, how come you got: $\phi(x)^k = \phi(x^k) = e'$. And finally when you concluded that $\phi (x^j) = e' \implies x^j = e$. How can you imply this result?
Thank you again for your precious time
4. I am not sure I understand, how come you got: $\phi(x)^k = \phi(x^k) = e'$
$\phi(x^k) = \phi(x) ^k$ because $\phi$ is a homomorphism. Since $x^k = e$ and $\phi$ is a group homomorphism, which means it maps identity to identity. Thus $\phi(x)^k = \phi(x^k) = e'$
. And finally when you concluded that $\phi (x^j) = e' \implies x^j = e$. How can you imply this result?
He assumed that \phi is injective (or one-one). And $\phi (x^j) = e' = \phi(e)$, thus injectivity forces $\phi (x^j) = \phi(e) \implies x^j = e$.
5. I am not sure I understand, how come you got:
X Є G
O(G)=n
X^n =e
f(X^n)=f(e)
f(X.X.X.X.X….X)=e’
f(X). f(X) . f(X) . f(X) . f(X)…… . f(X)=e’
(f(X))^n=e’
(f(X))^n=f(X^n)=e’
O(f(X))=n
O(H)=n
O(H)=O(G)
6. Thanks very much you guys. Now I understand it now. It makes sense to me due to your clear explanation. Cheers | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 27, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.950710654258728, "perplexity": 1944.1174318770857}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1393999654872/warc/CC-MAIN-20140305060734-00023-ip-10-183-142-35.ec2.internal.warc.gz"} |
https://metajuhoxazigycev.esteindesign.xyz/extended-covariant-products-book-14011nd.php | Last edited by Douzuru
Thursday, May 7, 2020 | History
4 edition of Extended covariant products found in the catalog.
Extended covariant products
R. Rousseau
# Extended covariant products
## by R. Rousseau
Written in English
Subjects:
• Von Neumann algebras -- Crossed products.
• Edition Notes
Classifications The Physical Object Other titles Extended covariant systems, a contribution to the study of crossed products of von Neumann algebras., Extended covariant systems. Statement by R. Rousseau. Series Verhandelingen van de Koninklijke Academie voor Wetenschappen, Letteren en Schone Kunsten van België, Klasse der Wetenschappen ;, jaarg. 43, 1981, nr. 171, Verhandelingen van de Koninklijke Academie voor Wetenschappen, Letteren en Schone Kunsten van België, Klasse der Wetenschappen ;, nr. 171. LC Classifications Q56 .V45 nr. 171, QA326 .V45 nr. 171 Pagination 59 p. ; Number of Pages 59 Open Library OL3520045M ISBN 10 906569658X LC Control Number 82103710
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It only takes a minute to sign up. Property of the covariant derivative. Ask Question Asked 3 years, 10 months ago. Active 3 years, 10 months ago. Viewed times 1. 0. Examples of how to use “covariant” in a sentence from the Cambridge Dictionary Labs.
Keep up to date with the latest blogs, books & events. Home; Contact Us; Cart; Questions? Call a 0 Items - \$ Missing: Extended covariant. The tensor product appears as a coproduct for commutative rings with unity, but as with the direct sum this definition is then extended to other categories. For abelian groups, the tensor product $${G\otimes H}$$ is the group generated by the ordered pairs $${g\otimes h}$$ linear over $${+}$$; as more structure is added, the tensor product is.
Covariant and Contravariant Tensors, Pseudo and Polar Scalars, Vectors, and Tensors. In this section, the concept of contravariant and covariant vectors is extended to tensors. Also, the contravariant (covariant) forms of the metric tensor are expressed as the dot product of a pair of contravariant (covariant) basis vectors. Covariance and contravariance are terms that are used in different ways in the theory of object-oriented programming and they sound advanced and difficult - but in fact the idea they they encapsulate is very, very simple. It is an idea that seems to originate in physics but in .
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Buy Exploring Covariant Electrodynamics through Solved Problems He has published more than papers in international journals and is the author of monographs on extended theories of gravity, gravitational lensing, cosmology, and general relativity.
Pages with related products. See and discover other items: physics problems. Buy Extended Lagrange and Hamilton Formalism for Point Mechanics and Covariant Hamilton Field Theory on FREE SHIPPING on qualified orders Extended Lagrange and Hamilton Formalism for Point Mechanics and Covariant Hamilton Field Theory: Struckmeier, Jurgen, Greiner, Walter, Reichau, Hermine: : Books.
This book is the first to describe a very successful objective unified field theory which emerged in and which is already mainstream physics -Einstein Cartan Evans (ECE)field latter completes the well known work of Einstein and Cartan,who from to sought to unify Extended covariant products book theory in physics with the principles of general principles are based on the need 5/5(1).
4 Covariant formulation of linear momentum and energy The relativistic momentum p and the energy Eare de ned as 8 >> >: p = mu = m 0u p 1 u2=c2 E= mc2 = m 0c2 p 1 2u=c2 where u is the velocity of the particle and its rest mass is m 0.
We have also have p Extended covariant products book = m 0c = constant, independent of the frame of reference (). If you change your book details, content, or pricing, it can take up to eight weeks for the information to update through Expanded Distribution.
Your book will still be available, but it will have the previous information until the information is updated. Expanded Distribution doesn't reflect changes in real time. writing this book is to make available a modern introductory textbook suitable for the first in-depth exposure to vectors and tensors.
Because of our interest in applications, it is our hope that this book will aid students in their efforts to use vectors and tensors in applied Size: 1MB. Audible Listen to Books & Original Audio Performances: Book Depository Books With Free Delivery Worldwide: Box Office Mojo Find Movie Box Office Data: ComiXology Thousands of Digital Comics: CreateSpace Indie Print Publishing Made Easy: DPReview Digital Photography: East Dane Designer Men's Fashion: Fabric Sewing, Quilting & Knitting Missing: Extended covariant.
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book is a humble step of efforts made by him to prove him to be a dedicated and striving teacher who has worked relentlessly in this field. This book fills the gap as methodology has been explained in a simple manner to enable students to understand easily. This book will prove to be a complete book for the students in this field.
Ram Nivas Professor,File Size: 1MB. This is to update and consolidate the extended use date information posted previously to assist with drug shortage (6/15/17 to present). Covariant differentiation for a contravariant vector Consider a vector V = V α e α (ie the tensor has contravariant components V α and coordinate basis vectors e α).
Using the product rule of derivation, the rate of change of the components Vα (of the vector V) with respect to x β. Covariant Electrodynamics: A Concise Guide 1st Edition Fulfillment by Amazon (FBA) is a service we offer sellers that lets them store their products in Amazon's fulfillment centers, and we directly pack, ship, and provide customer service for these products/5(2).
The concept of parallel transport along a curve C can be extended to the tensor algebra as well, by parallel transporting all vector arguments backwards to the starting point of C, applying the tensor, then parallel transporting the resulting vectors forward to the endpoint of C.
Extended Lagrange And Hamilton Formalism For Point Mechanics And Covariant Hamilton Field Theory by Jurgen Struckmeier,available at Book Depository with free delivery worldwide. Among mainstream OO languages, Java and C++ support covariant return types, while C# does not.
Adding the covariant return type was one of the first modifications of the C++ language approved by the standards committee in Scala and D also support covariant return types.
Covariant Hamiltonian Field Theory Under Dynamic Space-Time: Extended Hamilton–Lagrange Formalism in Field Theories; General U(N) Gauge Transformations in Extended Canonical Formalism; Readership: Graduate students and researchers in relativistic point mechanics and field theories.
Contact. Email ASHP. East-West Highway, Suite Bethesda, MD Missing: Extended covariant. In mathematics, the covariant derivative is a way of specifying a derivative along tangent vectors of a atively, the covariant derivative is a way of introducing and working with a connection on a manifold by means of a differential operator, to be contrasted with the approach given by a principal connection on the frame bundle – see affine connection.
Covariant and Contravariant Vectors Alok Kumar1 IISER, Bhopal ITI Campus (Gas Rahat) Building Govindpura, Bhopal - 23 India. Abstract Vector is a physical quantity and it does not depend on any co-ordinate system.
It need to be expanded in some basis for practical calculation and its components do depend on the chosen basis. The expansion in File Size: 75KB. of a tensor on a finite-dimensional vector space. A mapping of the space of tensors of a fixed type over into a space of covariant tensors over such that for any non-singular linear transformation of and is the definition of the covariant of a tensor with respect to the general linear is not arbitrary but belongs to a fixed subgroup, then one obtains the definition of a.
In object-oriented programming, a covariant return type of a method is one that can be replaced by a "narrower" type when the method is overridden in a subclass. A notable language in which this is a fairly common paradigm is C++.
C# does not support return type covariance; however it has been set out to be added as new language feature as of upcoming C# The duality between covariance and contravariance intervenes whenever a vector or tensor quantity is represented by its components, although modern differential geometry uses more sophisticated index-free methods to represent tensors.
In tensor analysis, a covariant vector varies more or less reciprocally to a corresponding contravariant vector. Expressions for lengths, areas and volumes of objects in the vector space can then be given in terms of tensors with covariant and contravariant.Analysis of covariance example with two categories and type II sum of squares This example uses type II sum of squares, but otherwise follows the example in the Handbook.
The parameter estimates are calculated differently in R, so the calculation of the intercepts of the lines is slightly different. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5217843651771545, "perplexity": 2395.9800462600488}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-45/segments/1603107863364.0/warc/CC-MAIN-20201019145901-20201019175901-00673.warc.gz"} |
https://www.gradesaver.com/textbooks/math/trigonometry/trigonometry-7th-edition/chapter-3-section-3-2-radians-and-degrees-3-2-problem-set-page-134/94 | ## Trigonometry 7th Edition
$({\frac{\pi}{6},5}),({{\frac{\pi}{3}},{\frac{5}{2}})},({\frac{2\pi}{3},-5}),({{\pi},{\frac{5}{2}}}),({\frac{7\pi}{6},5})$
given $y=5 \cos(2x-\frac{\pi}{3})$ when $x={\frac{\pi}{6}}$ then $y=5\cos{0}=5$ $x={\frac{\pi}{3}}$ then $y=5\cos{\frac{\pi}{3}}={\frac{5}{2}}$ $x={\frac{2\pi}{3}}$ then $y=5\cos{\pi}=-5$ $x={{\pi}}$ then $y=5\cos{\frac{5\pi}{3}}={\frac{5}{2}}$ $x={\frac{7\pi}{6}}$ then $y=3.\cos{2\pi}=5$ then the final answer is : $({\frac{\pi}{6},5}),({{\frac{\pi}{3}},{\frac{5}{2}})},({\frac{2\pi}{3},-5}),({{\pi},{\frac{5}{2}}}),({\frac{7\pi}{6},5})$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.999678373336792, "perplexity": 135.1046008612994}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496669847.1/warc/CC-MAIN-20191118205402-20191118233402-00187.warc.gz"} |
https://link.springer.com/article/10.1007%2Fs10898-019-00831-9 | Advertisement
Journal of Global Optimization
, Volume 75, Issue 4, pp 885–919
# A new bounded degree hierarchy with SOCP relaxations for global polynomial optimization and conic convex semi-algebraic programs
• T. D. Chuong
• V. Jeyakumar
• G. Li
Article
• 181 Downloads
## Abstract
In this paper, we propose a bounded degree hierarchy of both primal and dual conic programming relaxations involving both semi-definite and second-order cone constraints for solving a nonconvex polynomial optimization problem with a bounded feasible set. This hierarchy makes use of some key aspects of the convergent linear programming relaxations of polynomial optimization problems (Lasserre in Moments, positive polynomials and their applications, World Scientific, Singapore, 2010) associated with Krivine–Stengle’s certificate of positivity in real algebraic geometry and some advantages of the scaled diagonally dominant sum of squares (SDSOS) polynomials (Ahmadi and Hall in Math Oper Res, 2019. ; Ahmadi and Majumdar in SIAM J Appl Algebra Geom 3:193–230, 2019). We show that the values of both primal and dual relaxations converge to the global optimal value of the original polynomial optimization problem under some technical assumptions. Our hierarchy, which extends the so-called bounded degree Lasserre hierarchy (Lasserre et al. in Eur J Comput Optim 5:87–117, 2017), has a useful feature that the size and the number of the semi-definite and second-order cone constraints of the relaxations are fixed and independent of the step or level of the approximation in the hierarchy. As a special case, we provide a convergent bounded degree second-order cone programming (SOCP) hierarchy for solving polynomial optimization problems. We then present finite convergence at step one of the SOCP hierarchy for classes of polynomial optimization problems. This includes one-step convergence for a new class of first-order SDSOS-convex polynomial programs. In this case, we also show how a global solution is recovered from the level one SOCP relaxation. We finally derive a corresponding convergent conic linear programming hierarchy for conic-convex semi-algebraic programs. Whenever the semi-algebraic set of the conic-convex program is described by concave polynomial inequalities, we show further that the values of the relaxation problems converge to the common value of the convex program and its Lagrangian dual under a constraint qualification.
## Keywords
Nonconvex polynomial optimization Conic programming relaxations Global optimization Cone-convex polynomial programs Convex semi-algebraic programs
## Notes
### Acknowledgements
The authors would like to thank the referees for their valuable comments and suggestions which greatly improved the original version of the paper.
## References
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## Copyright information
© Springer Science+Business Media, LLC, part of Springer Nature 2019
## Authors and Affiliations
1. 1.Department of Applied MathematicsUniversity of New South WalesSydneyAustralia
2. 2.Department of Mathematics and ApplicationsSaigon UniversityHo Chi Minh CityVietnam | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8724125027656555, "perplexity": 6882.393972392967}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575540486979.4/warc/CC-MAIN-20191206073120-20191206101120-00272.warc.gz"} |
https://dealii.org/developer/doxygen/deal.II/step_23.html | Reference documentation for deal.II version GIT 91e6c87029 2023-02-08 03:05:02+00:00
The step-23 tutorial program
This tutorial depends on step-4.
1. Introduction
2. The commented program
1. Results
2. The plain program
# Introduction
Note
The material presented here is also discussed in video lecture 28. (All video lectures are also available here.)
This is the first of a number of tutorial programs that will finally cover "real" time-dependent problems, not the slightly odd form of time dependence found in step-18 or the DAE model of step-21. In particular, this program introduces the wave equation in a bounded domain. Later, step-24 will consider an example of absorbing boundary conditions, and step-25 a kind of nonlinear wave equation producing solutions called solitons.
The wave equation in its prototypical form reads as follows: find $$u(x,t), x\in\Omega, t\in[0,T]$$ that satisfies
\begin{eqnarray*} \frac{\partial^2 u}{\partial t^2} - \Delta u &=& f \qquad \textrm{in}\ \Omega\times [0,T], \\ u(x,t) &=& g \qquad \textrm{on}\ \partial\Omega\times [0,T], \\ u(x,0) &=& u_0(x) \qquad \textrm{in}\ \Omega, \\ \frac{\partial u(x,0)}{\partial t} &=& u_1(x) \qquad \textrm{in}\ \Omega. \end{eqnarray*}
Note that since this is an equation with second-order time derivatives, we need to pose two initial conditions, one for the value and one for the time derivative of the solution.
Physically, the equation describes the motion of an elastic medium. In 2-d, one can think of how a membrane moves if subjected to a force. The Dirichlet boundary conditions above indicate that the membrane is clamped at the boundary at a height $$g(x,t)$$ (this height might be moving as well — think of people holding a blanket and shaking it up and down). The first initial condition equals the initial deflection of the membrane, whereas the second one gives its velocity. For example, one could think of pushing the membrane down with a finger and then letting it go at $$t=0$$ (nonzero deflection but zero initial velocity), or hitting it with a hammer at $$t=0$$ (zero deflection but nonzero velocity). Both cases would induce motion in the membrane.
### Time discretization
#### Method of lines or Rothe's method?
There is a long-standing debate in the numerical analysis community over whether a discretization of time dependent equations should involve first discretizing the time variable leading to a stationary PDE at each time step that is then solved using standard finite element techniques (this is called the Rothe method), or whether one should first discretize the spatial variables, leading to a large system of ordinary differential equations that can then be handled by one of the usual ODE solvers (this is called the method of lines).
Both of these methods have advantages and disadvantages. Traditionally, people have preferred the method of lines, since it allows to use the very well developed machinery of high-order ODE solvers available for the rather stiff ODEs resulting from this approach, including step length control and estimation of the temporal error.
On the other hand, Rothe's method becomes awkward when using higher-order time stepping method, since one then has to write down a PDE that couples the solution of the present time step not only with that at the previous time step, but possibly also even earlier solutions, leading to a significant number of terms.
For these reasons, the method of lines was the method of choice for a long time. However, it has one big drawback: if we discretize the spatial variable first, leading to a large ODE system, we have to choose a mesh once and for all. If we are willing to do this, then this is a legitimate and probably superior approach.
If, on the other hand, we are looking at the wave equation and many other time dependent problems, we find that the character of a solution changes as time progresses. For example, for the wave equation, we may have a single wave travelling through the domain, where the solution is smooth or even constant in front of and behind the wave — adaptivity would be really useful for such cases, but the key is that the area where we need to refine the mesh changes from time step to time step!
If we intend to go that way, i.e. choose a different mesh for each time step (or set of time steps), then the method of lines is not appropriate any more: instead of getting one ODE system with a number of variables equal to the number of unknowns in the finite element mesh, our number of unknowns now changes all the time, a fact that standard ODE solvers are certainly not prepared to deal with at all. On the other hand, for the Rothe method, we just get a PDE for each time step that we may choose to discretize independently of the mesh used for the previous time step; this approach is not without perils and difficulties, but at least is a sensible and well-defined procedure.
For all these reasons, for the present program, we choose to use the Rothe method for discretization, i.e. we first discretize in time and then in space. We will not actually use adaptive meshes at all, since this involves a large amount of additional code, but we will comment on this some more in the results section below.
#### Rothe's method!
Given these considerations, here is how we will proceed: let us first define a simple time stepping method for this second order problem, and then in a second step do the spatial discretization, i.e. we will follow Rothe's approach.
For the first step, let us take a little detour first: in order to discretize a second time derivative, we can either discretize it directly, or we can introduce an additional variable and transform the system into a first order system. In many cases, this turns out to be equivalent, but dealing with first order systems is often simpler. To this end, let us introduce
$v = \frac{\partial u}{\partial t},$
and call this variable the velocity for obvious reasons. We can then reformulate the original wave equation as follows:
\begin{eqnarray*} \frac{\partial u}{\partial t} - v &=& 0 \qquad \textrm{in}\ \Omega\times [0,T], \\ \frac{\partial v}{\partial t} - \Delta u &=& f \qquad \textrm{in}\ \Omega\times [0,T], \\ u(x,t) &=& g \qquad \textrm{on}\ \partial\Omega\times [0,T], \\ u(x,0) &=& u_0(x) \qquad \textrm{in}\ \Omega, \\ v(x,0) &=& u_1(x) \qquad \textrm{in}\ \Omega. \end{eqnarray*}
The advantage of this formulation is that it now only contains first time derivatives for both variables, for which it is simple to write down time stepping schemes. Note that we do not have boundary conditions for $$v$$ at first. However, we could enforce $$v=\frac{\partial g}{\partial t}$$ on the boundary. It turns out in numerical examples that this is actually necessary: without doing so the solution doesn't look particularly wrong, but the Crank-Nicolson scheme does not conserve energy if one doesn't enforce these boundary conditions.
With this formulation, let us introduce the following time discretization where a superscript $$n$$ indicates the number of a time step and $$k=t_n-t_{n-1}$$ is the length of the present time step:
\begin{eqnarray*} \frac{u^n - u^{n-1}}{k} - \left[\theta v^n + (1-\theta) v^{n-1}\right] &=& 0, \\ \frac{v^n - v^{n-1}}{k} - \Delta\left[\theta u^n + (1-\theta) u^{n-1}\right] &=& \theta f^n + (1-\theta) f^{n-1}. \end{eqnarray*}
Note how we introduced a parameter $$\theta$$ here. If we chose $$\theta=0$$, for example, the first equation would reduce to $$\frac{u^n - u^{n-1}}{k} - v^{n-1} = 0$$, which is well-known as the forward or explicit Euler method. On the other hand, if we set $$\theta=1$$, then we would get $$\frac{u^n - u^{n-1}}{k} - v^n = 0$$, which corresponds to the backward or implicit Euler method. Both these methods are first order accurate methods. They are simple to implement, but they are not really very accurate.
The third case would be to choose $$\theta=\frac 12$$. The first of the equations above would then read $$\frac{u^n - u^{n-1}}{k} - \frac 12 \left[v^n + v^{n-1}\right] = 0$$. This method is known as the Crank-Nicolson method and has the advantage that it is second order accurate. In addition, it has the nice property that it preserves the energy in the solution (physically, the energy is the sum of the kinetic energy of the particles in the membrane plus the potential energy present due to the fact that it is locally stretched; this quantity is a conserved one in the continuous equation, but most time stepping schemes do not conserve it after time discretization). Since $$v^n$$ also appears in the equation for $$u^n$$, the Crank-Nicolson scheme is also implicit.
In the program, we will leave $$\theta$$ as a parameter, so that it will be easy to play with it. The results section will show some numerical evidence comparing the different schemes.
The equations above (called the semidiscretized equations because we have only discretized the time, but not space), can be simplified a bit by eliminating $$v^n$$ from the first equation and rearranging terms. We then get
\begin{eqnarray*} \left[ 1-k^2\theta^2\Delta \right] u^n &=& \left[ 1+k^2\theta(1-\theta)\Delta\right] u^{n-1} + k v^{n-1} + k^2\theta\left[\theta f^n + (1-\theta) f^{n-1}\right],\\ v^n &=& v^{n-1} + k\Delta\left[ \theta u^n + (1-\theta) u^{n-1}\right] + k\left[\theta f^n + (1-\theta) f^{n-1}\right]. \end{eqnarray*}
In this form, we see that if we are given the solution $$u^{n-1},v^{n-1}$$ of the previous timestep, that we can then solve for the variables $$u^n,v^n$$ separately, i.e. one at a time. This is convenient. In addition, we recognize that the operator in the first equation is positive definite, and the second equation looks particularly simple.
### Space discretization
We have now derived equations that relate the approximate (semi-discrete) solution $$u^n(x)$$ and its time derivative $$v^n(x)$$ at time $$t_n$$ with the solutions $$u^{n-1}(x),v^{n-1}(x)$$ of the previous time step at $$t_{n-1}$$. The next step is to also discretize the spatial variable using the usual finite element methodology. To this end, we multiply each equation with a test function, integrate over the entire domain, and integrate by parts where necessary. This leads to
\begin{eqnarray*} (u^n,\varphi) + k^2\theta^2(\nabla u^n,\nabla \varphi) &=& (u^{n-1},\varphi) - k^2\theta(1-\theta)(\nabla u^{n-1},\nabla \varphi) + k(v^{n-1},\varphi) + k^2\theta \left[ \theta (f^n,\varphi) + (1-\theta) (f^{n-1},\varphi) \right], \\ (v^n,\varphi) &=& (v^{n-1},\varphi) - k\left[ \theta (\nabla u^n,\nabla\varphi) + (1-\theta) (\nabla u^{n-1},\nabla \varphi)\right] + k \left[ \theta (f^n,\varphi) + (1-\theta) (f^{n-1},\varphi) \right]. \end{eqnarray*}
It is then customary to approximate $$u^n(x) \approx u^n_h(x) = \sum_i U_i^n\phi_i^n(x)$$, where $$\phi_i^n(x)$$ are the shape functions used for the discretization of the $$n$$-th time step and $$U_i^n$$ are the unknown nodal values of the solution. Similarly, $$v^n(x) \approx v^n_h(x) = \sum_i V_i^n\phi_i^n(x)$$. Finally, we have the solutions of the previous time step, $$u^{n-1}(x) \approx u^{n-1}_h(x) = \sum_i U_i^{n-1}\phi_i^{n-1}(x)$$ and $$v^{n-1}(x) \approx v^{n-1}_h(x) = \sum_i V_i^{n-1}\phi_i^{n-1}(x)$$. Note that since the solution of the previous time step has already been computed by the time we get to time step $$n$$, $$U^{n-1},V^{n-1}$$ are known. Furthermore, note that the solutions of the previous step may have been computed on a different mesh, so we have to use shape functions $$\phi^{n-1}_i(x)$$.
If we plug these expansions into above equations and test with the test functions from the present mesh, we get the following linear system:
\begin{eqnarray*} (M^n + k^2\theta^2 A^n)U^n &=& M^{n,n-1}U^{n-1} - k^2\theta(1-\theta) A^{n,n-1}U^{n-1} + kM^{n,n-1}V^{n-1} + k^2\theta \left[ \theta F^n + (1-\theta) F^{n-1} \right], \\ M^nV^n &=& M^{n,n-1}V^{n-1} - k\left[ \theta A^n U^n + (1-\theta) A^{n,n-1} U^{n-1}\right] + k \left[ \theta F^n + (1-\theta) F^{n-1} \right], \end{eqnarray*}
where
\begin{eqnarray*} M^n_{ij} &=& (\phi_i^n, \phi_j^n), \\ A^n_{ij} &=& (\nabla\phi_i^n, \nabla\phi_j^n), \\ M^{n,n-1}_{ij} &=& (\phi_i^n, \phi_j^{n-1}), \\ A^{n,n-1}_{ij} &=& (\nabla\phi_i^n, \nabla\phi_j^{n-1}), \\ F^n_{i} &=& (f^n,\phi_i^n), \\ F^{n-1}_{i} &=& (f^{n-1},\phi_i^n). \end{eqnarray*}
If we solve these two equations, we can move the solution one step forward and go on to the next time step.
It is worth noting that if we choose the same mesh on each time step (as we will in fact do in the program below), then we have the same shape functions on time step $$n$$ and $$n-1$$, i.e. $$\phi^n_i=\phi_i^{n-1}=\phi_i$$. Consequently, we get $$M^n=M^{n,n-1}=M$$ and $$A^n=A^{n,n-1}=A$$. On the other hand, if we had used different shape functions, then we would have to compute integrals that contain shape functions defined on two meshes. This is a somewhat messy process that we omit here, but that is treated in some detail in step-28.
Under these conditions (i.e. a mesh that doesn't change), one can optimize the solution procedure a bit by basically eliminating the solution of the second linear system. We will discuss this in the introduction of the step-25 program.
### Energy conservation
One way to compare the quality of a time stepping scheme is to see whether the numerical approximation preserves conservation properties of the continuous equation. For the wave equation, the natural quantity to look at is the energy. By multiplying the wave equation by $$u_t$$, integrating over $$\Omega$$, and integrating by parts where necessary, we find that
$\frac{d}{d t} \left[\frac 12 \int_\Omega \left(\frac{\partial u}{\partial t}\right)^2 + (\nabla u)^2 \; dx\right] = \int_\Omega f \frac{\partial u}{\partial t} \; dx + \int_{\partial\Omega} n\cdot\nabla u \frac{\partial g}{\partial t} \; dx.$
By consequence, in absence of body forces and constant boundary values, we get that
$E(t) = \frac 12 \int_\Omega \left(\frac{\partial u}{\partial t}\right)^2 + (\nabla u)^2 \; dx$
is a conserved quantity, i.e. one that doesn't change with time. We will compute this quantity after each time step. It is straightforward to see that if we replace $$u$$ by its finite element approximation, and $$\frac{\partial u}{\partial t}$$ by the finite element approximation of the velocity $$v$$, then
$E(t_n) = \frac 12 \left<V^n, M^n V^n\right> + \frac 12 \left<U^n, A^n U^n\right>.$
As we will see in the results section, the Crank-Nicolson scheme does indeed conserve the energy, whereas neither the forward nor the backward Euler scheme do.
### Who are Courant, Friedrichs, and Lewy?
One of the reasons why the wave equation is not easy to solve numerically is that explicit time discretizations are only stable if the time step is small enough. In particular, it is coupled to the spatial mesh width $$h$$. For the lowest order discretization we use here, the relationship reads
$k\le \frac hc$
where $$c$$ is the wave speed, which in our formulation of the wave equation has been normalized to one. Consequently, unless we use the implicit schemes with $$\theta>0$$, our solutions will not be numerically stable if we violate this restriction. Implicit schemes do not have this restriction for stability, but they become inaccurate if the time step is too large.
This condition was first recognized by Courant, Friedrichs, and Lewy — in 1928, long before computers became available for numerical computations! (This result appeared in the German language article R. Courant, K. Friedrichs and H. Lewy: Über die partiellen Differenzengleichungen der mathematischen Physik, Mathematische Annalen, vol. 100, no. 1, pages 32-74, 1928.) This condition on the time step is most frequently just referred to as the CFL condition. Intuitively, the CFL condition says that the time step must not be larger than the time it takes a wave to cross a single cell.
In the program, we will refine the square $$[-1,1]^2$$ seven times uniformly, giving a mesh size of $$h=\frac 1{64}$$, which is what we set the time step to. The fact that we set the time step and mesh size individually in two different places is error prone: it is too easy to refine the mesh once more but forget to also adjust the time step. step-24 shows a better way how to keep these things in sync.
### The test case
Although the program has all the hooks to deal with nonzero initial and boundary conditions and body forces, we take a simple case where the domain is a square $$[-1,1]^2$$ and
\begin{eqnarray*} f &=& 0, \\ u_0 &=& 0, \\ u_1 &=& 0, \\ g &=& \left\{\begin{matrix}\sin (4\pi t) &\qquad& \text{for }\ t\le \frac 12, x=-1, -\frac 13<y<\frac 13 \\ 0 &&\text{otherwise} \end{matrix} \right. \end{eqnarray*}
This corresponds to a membrane initially at rest and clamped all around, where someone is waving a part of the clamped boundary once up and down, thereby shooting a wave into the domain.
# The commented program
### Include files
We start with the usual assortment of include files that we've seen in so many of the previous tests:
Here are the only three include files of some new interest: The first one is already used, for example, for the VectorTools::interpolate_boundary_values and MatrixTools::apply_boundary_values functions. However, we here use another function in that class, VectorTools::project to compute our initial values as the $$L^2$$ projection of the continuous initial values. Furthermore, we use VectorTools::create_right_hand_side to generate the integrals $$(f^n,\phi^n_i)$$. These were previously always generated by hand in assemble_system or similar functions in application code. However, we're too lazy to do that here, so simply use a library function:
In a very similar vein, we are also too lazy to write the code to assemble mass and Laplace matrices, although it would have only taken copying the relevant code from any number of previous tutorial programs. Rather, we want to focus on the things that are truly new to this program and therefore use the MatrixCreator::create_mass_matrix and MatrixCreator::create_laplace_matrix functions. They are declared here:
Finally, here is an include file that contains all sorts of tool functions that one sometimes needs. In particular, we need the Utilities::int_to_string class that, given an integer argument, returns a string representation of it. It is particularly useful since it allows for a second parameter indicating the number of digits to which we want the result padded with leading zeros. We will use this to write output files that have the form solution-XXX.vtu where XXX denotes the number of the time step and always consists of three digits even if we are still in the single or double digit time steps.
The last step is as in all previous programs:
namespace Step23
{
using namespace dealii;
### The WaveEquation class
Next comes the declaration of the main class. It's public interface of functions is like in most of the other tutorial programs. Worth mentioning is that we now have to store four matrices instead of one: the mass matrix $$M$$, the Laplace matrix $$A$$, the matrix $$M+k^2\theta^2A$$ used for solving for $$U^n$$, and a copy of the mass matrix with boundary conditions applied used for solving for $$V^n$$. Note that it is a bit wasteful to have an additional copy of the mass matrix around. We will discuss strategies for how to avoid this in the section on possible improvements.
Likewise, we need solution vectors for $$U^n,V^n$$ as well as for the corresponding vectors at the previous time step, $$U^{n-1},V^{n-1}$$. The system_rhs will be used for whatever right hand side vector we have when solving one of the two linear systems in each time step. These will be solved in the two functions solve_u and solve_v.
Finally, the variable theta is used to indicate the parameter $$\theta$$ that is used to define which time stepping scheme to use, as explained in the introduction. The rest is self-explanatory.
template <int dim>
class WaveEquation
{
public:
WaveEquation();
void run();
private:
void setup_system();
void solve_u();
void solve_v();
void output_results() const;
DoFHandler<dim> dof_handler;
SparsityPattern sparsity_pattern;
SparseMatrix<double> laplace_matrix;
Vector<double> solution_u, solution_v;
Vector<double> old_solution_u, old_solution_v;
Vector<double> system_rhs;
double time_step;
double time;
unsigned int timestep_number;
const double theta;
};
Definition: fe_q.h:551
void mass_matrix(FullMatrix< double > &M, const FEValuesBase< dim > &fe, const double factor=1.)
Definition: l2.h:58
void run(const Iterator &begin, const typename identity< Iterator >::type &end, Worker worker, Copier copier, const ScratchData &sample_scratch_data, const CopyData &sample_copy_data, const unsigned int queue_length, const unsigned int chunk_size)
Definition: work_stream.h:474
const ::parallel::distributed::Triangulation< dim, spacedim > * triangulation
### Equation data
Before we go on filling in the details of the main class, let us define the equation data corresponding to the problem, i.e. initial and boundary values for both the solution $$u$$ and its time derivative $$v$$, as well as a right hand side class. We do so using classes derived from the Function class template that has been used many times before, so the following should not be a surprise.
Let's start with initial values and choose zero for both the value $$u$$ as well as its time derivative, the velocity $$v$$:
template <int dim>
class InitialValuesU : public Function<dim>
{
public:
virtual double value(const Point<dim> & /*p*/,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
return 0;
}
};
template <int dim>
class InitialValuesV : public Function<dim>
{
public:
virtual double value(const Point<dim> & /*p*/,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
return 0;
}
};
virtual RangeNumberType value(const Point< dim > &p, const unsigned int component=0) const
Definition: point.h:111
#define Assert(cond, exc)
Definition: exceptions.h:1583
static ::ExceptionBase & ExcIndexRange(std::size_t arg1, std::size_t arg2, std::size_t arg3)
Secondly, we have the right hand side forcing term. Boring as we are, we choose zero here as well:
template <int dim>
class RightHandSide : public Function<dim>
{
public:
virtual double value(const Point<dim> & /*p*/,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
return 0;
}
};
Finally, we have boundary values for $$u$$ and $$v$$. They are as described in the introduction, one being the time derivative of the other:
template <int dim>
class BoundaryValuesU : public Function<dim>
{
public:
virtual double value(const Point<dim> & p,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
if ((this->get_time() <= 0.5) && (p[0] < 0) && (p[1] < 1. / 3) &&
(p[1] > -1. / 3))
return std::sin(this->get_time() * 4 * numbers::PI);
else
return 0;
}
};
template <int dim>
class BoundaryValuesV : public Function<dim>
{
public:
virtual double value(const Point<dim> & p,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
if ((this->get_time() <= 0.5) && (p[0] < 0) && (p[1] < 1. / 3) &&
(p[1] > -1. / 3))
return (std::cos(this->get_time() * 4 * numbers::PI) * 4 * numbers::PI);
else
return 0;
}
};
numbers::NumberTraits< double >::real_type get_time() const
static constexpr double PI
Definition: numbers.h:248
::VectorizedArray< Number, width > sin(const ::VectorizedArray< Number, width > &)
### Implementation of the WaveEquation class
The implementation of the actual logic is actually fairly short, since we relegate things like assembling the matrices and right hand side vectors to the library. The rest boils down to not much more than 130 lines of actual code, a significant fraction of which is boilerplate code that can be taken from previous example programs (e.g. the functions that solve linear systems, or that generate output).
Let's start with the constructor (for an explanation of the choice of time step, see the section on Courant, Friedrichs, and Lewy in the introduction):
template <int dim>
WaveEquation<dim>::WaveEquation()
: fe(1)
, dof_handler(triangulation)
, time_step(1. / 64)
, time(time_step)
, timestep_number(1)
, theta(0.5)
{}
#### WaveEquation::setup_system
The next function is the one that sets up the mesh, DoFHandler, and matrices and vectors at the beginning of the program, i.e. before the first time step. The first few lines are pretty much standard if you've read through the tutorial programs at least up to step-6:
template <int dim>
void WaveEquation<dim>::setup_system()
{
triangulation.refine_global(7);
std::cout << "Number of active cells: " << triangulation.n_active_cells()
<< std::endl;
dof_handler.distribute_dofs(fe);
std::cout << "Number of degrees of freedom: " << dof_handler.n_dofs()
<< std::endl
<< std::endl;
DynamicSparsityPattern dsp(dof_handler.n_dofs(), dof_handler.n_dofs());
sparsity_pattern.copy_from(dsp);
void make_sparsity_pattern(const DoFHandler< dim, spacedim > &dof_handler, SparsityPatternBase &sparsity_pattern, const AffineConstraints< number > &constraints=AffineConstraints< number >(), const bool keep_constrained_dofs=true, const types::subdomain_id subdomain_id=numbers::invalid_subdomain_id)
void hyper_cube(Triangulation< dim, spacedim > &tria, const double left=0., const double right=1., const bool colorize=false)
Then comes a block where we have to initialize the 3 matrices we need in the course of the program: the mass matrix, the Laplace matrix, and the matrix $$M+k^2\theta^2A$$ used when solving for $$U^n$$ in each time step.
When setting up these matrices, note that they all make use of the same sparsity pattern object. Finally, the reason why matrices and sparsity patterns are separate objects in deal.II (unlike in many other finite element or linear algebra classes) becomes clear: in a significant fraction of applications, one has to hold several matrices that happen to have the same sparsity pattern, and there is no reason for them not to share this information, rather than re-building and wasting memory on it several times.
After initializing all of these matrices, we call library functions that build the Laplace and mass matrices. All they need is a DoFHandler object and a quadrature formula object that is to be used for numerical integration. Note that in many respects these functions are better than what we would usually do in application programs, for example because they automatically parallelize building the matrices if multiple processors are available in a machine: for more information see the documentation of WorkStream or the Parallel computing with multiple processors module. The matrices for solving linear systems will be filled in the run() method because we need to re-apply boundary conditions every time step.
mass_matrix.reinit(sparsity_pattern);
laplace_matrix.reinit(sparsity_pattern);
matrix_u.reinit(sparsity_pattern);
matrix_v.reinit(sparsity_pattern);
QGauss<dim>(fe.degree + 1),
QGauss<dim>(fe.degree + 1),
laplace_matrix);
void create_mass_matrix(const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof, const Quadrature< dim > &q, SparseMatrixType &matrix, const Function< spacedim, typename SparseMatrixType::value_type > *const a=nullptr, const AffineConstraints< typename SparseMatrixType::value_type > &constraints=AffineConstraints< typename SparseMatrixType::value_type >())
void create_laplace_matrix(const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof, const Quadrature< dim > &q, SparseMatrixType &matrix, const Function< spacedim, typename SparseMatrixType::value_type > *const a=nullptr, const AffineConstraints< typename SparseMatrixType::value_type > &constraints=AffineConstraints< typename SparseMatrixType::value_type >())
The rest of the function is spent on setting vector sizes to the correct value. The final line closes the hanging node constraints object. Since we work on a uniformly refined mesh, no constraints exist or have been computed (i.e. there was no need to call DoFTools::make_hanging_node_constraints as in other programs), but we need a constraints object in one place further down below anyway.
solution_u.reinit(dof_handler.n_dofs());
solution_v.reinit(dof_handler.n_dofs());
old_solution_u.reinit(dof_handler.n_dofs());
old_solution_v.reinit(dof_handler.n_dofs());
system_rhs.reinit(dof_handler.n_dofs());
constraints.close();
}
#### WaveEquation::solve_u and WaveEquation::solve_v
The next two functions deal with solving the linear systems associated with the equations for $$U^n$$ and $$V^n$$. Both are not particularly interesting as they pretty much follow the scheme used in all the previous tutorial programs.
One can make little experiments with preconditioners for the two matrices we have to invert. As it turns out, however, for the matrices at hand here, using Jacobi or SSOR preconditioners reduces the number of iterations necessary to solve the linear system slightly, but due to the cost of applying the preconditioner it is no win in terms of run-time. It is not much of a loss either, but let's keep it simple and just do without:
template <int dim>
void WaveEquation<dim>::solve_u()
{
SolverControl solver_control(1000, 1e-8 * system_rhs.l2_norm());
SolverCG<Vector<double>> cg(solver_control);
cg.solve(matrix_u, solution_u, system_rhs, PreconditionIdentity());
std::cout << " u-equation: " << solver_control.last_step()
<< " CG iterations." << std::endl;
}
template <int dim>
void WaveEquation<dim>::solve_v()
{
SolverControl solver_control(1000, 1e-8 * system_rhs.l2_norm());
SolverCG<Vector<double>> cg(solver_control);
cg.solve(matrix_v, solution_v, system_rhs, PreconditionIdentity());
std::cout << " v-equation: " << solver_control.last_step()
<< " CG iterations." << std::endl;
}
SymmetricTensor< 2, dim, Number > e(const Tensor< 2, dim, Number > &F)
#### WaveEquation::output_results
Likewise, the following function is pretty much what we've done before. The only thing worth mentioning is how here we generate a string representation of the time step number padded with leading zeros to 3 character length using the Utilities::int_to_string function's second argument.
template <int dim>
void WaveEquation<dim>::output_results() const
{
DataOut<dim> data_out;
data_out.attach_dof_handler(dof_handler);
data_out.build_patches();
const std::string filename =
"solution-" + Utilities::int_to_string(timestep_number, 3) + ".vtu";
void attach_dof_handler(const DoFHandler< dim, spacedim > &)
void add_data_vector(const VectorType &data, const std::vector< std::string > &names, const DataVectorType type=type_automatic, const std::vector< DataComponentInterpretation::DataComponentInterpretation > &data_component_interpretation={})
virtual void build_patches(const unsigned int n_subdivisions=0)
Definition: data_out.cc:1063
std::string int_to_string(const unsigned int value, const unsigned int digits=numbers::invalid_unsigned_int)
Definition: utilities.cc:473
Like step-15, since we write output at every time step (and the system we have to solve is relatively easy), we instruct DataOut to use the zlib compression algorithm that is optimized for speed instead of disk usage since otherwise plotting the output becomes a bottleneck:
data_out.set_flags(vtk_flags);
std::ofstream output(filename);
data_out.write_vtu(output);
}
void write_vtu(std::ostream &out) const
void set_flags(const FlagType &flags)
DataOutBase::CompressionLevel compression_level
#### WaveEquation::run
The following is really the only interesting function of the program. It contains the loop over all time steps, but before we get to that we have to set up the grid, DoFHandler, and matrices. In addition, we have to somehow get started with initial values. To this end, we use the VectorTools::project function that takes an object that describes a continuous function and computes the $$L^2$$ projection of this function onto the finite element space described by the DoFHandler object. Can't be any simpler than that:
template <int dim>
{
setup_system();
VectorTools::project(dof_handler,
constraints,
QGauss<dim>(fe.degree + 1),
InitialValuesU<dim>(),
old_solution_u);
VectorTools::project(dof_handler,
constraints,
QGauss<dim>(fe.degree + 1),
InitialValuesV<dim>(),
old_solution_v);
void project(const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof, const AffineConstraints< typename VectorType::value_type > &constraints, const Quadrature< dim > &quadrature, const Function< spacedim, typename VectorType::value_type > &function, VectorType &vec, const bool enforce_zero_boundary=false, const Quadrature< dim - 1 > &q_boundary=(dim > 1 ? QGauss< dim - 1 >(2) :Quadrature< dim - 1 >(0)), const bool project_to_boundary_first=false)
The next thing is to loop over all the time steps until we reach the end time ( $$T=5$$ in this case). In each time step, we first have to solve for $$U^n$$, using the equation $$(M^n + k^2\theta^2 A^n)U^n =$$ $$(M^{n,n-1} - k^2\theta(1-\theta) A^{n,n-1})U^{n-1} + kM^{n,n-1}V^{n-1} +$$ $$k\theta \left[k \theta F^n + k(1-\theta) F^{n-1} \right]$$. Note that we use the same mesh for all time steps, so that $$M^n=M^{n,n-1}=M$$ and $$A^n=A^{n,n-1}=A$$. What we therefore have to do first is to add up $$MU^{n-1} - k^2\theta(1-\theta) AU^{n-1} + kMV^{n-1}$$ and the forcing terms, and put the result into the system_rhs vector. (For these additions, we need a temporary vector that we declare before the loop to avoid repeated memory allocations in each time step.)
The one thing to realize here is how we communicate the time variable to the object describing the right hand side: each object derived from the Function class has a time field that can be set using the Function::set_time and read by Function::get_time. In essence, using this mechanism, all functions of space and time are therefore considered functions of space evaluated at a particular time. This matches well what we typically need in finite element programs, where we almost always work on a single time step at a time, and where it never happens that, for example, one would like to evaluate a space-time function for all times at any given spatial location.
Vector<double> tmp(solution_u.size());
Vector<double> forcing_terms(solution_u.size());
for (; time <= 5; time += time_step, ++timestep_number)
{
std::cout << "Time step " << timestep_number << " at t=" << time
<< std::endl;
mass_matrix.vmult(system_rhs, old_solution_u);
mass_matrix.vmult(tmp, old_solution_v);
laplace_matrix.vmult(tmp, old_solution_u);
system_rhs.add(-theta * (1 - theta) * time_step * time_step, tmp);
RightHandSide<dim> rhs_function;
rhs_function.set_time(time);
QGauss<dim>(fe.degree + 1),
rhs_function,
tmp);
forcing_terms = tmp;
forcing_terms *= theta * time_step;
rhs_function.set_time(time - time_step);
QGauss<dim>(fe.degree + 1),
rhs_function,
tmp);
forcing_terms.add((1 - theta) * time_step, tmp);
void create_right_hand_side(const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof, const Quadrature< dim > &q, const Function< spacedim, typename VectorType::value_type > &rhs, VectorType &rhs_vector, const AffineConstraints< typename VectorType::value_type > &constraints=AffineConstraints< typename VectorType::value_type >())
After so constructing the right hand side vector of the first equation, all we have to do is apply the correct boundary values. As for the right hand side, this is a space-time function evaluated at a particular time, which we interpolate at boundary nodes and then use the result to apply boundary values as we usually do. The result is then handed off to the solve_u() function:
{
BoundaryValuesU<dim> boundary_values_u_function;
boundary_values_u_function.set_time(time);
std::map<types::global_dof_index, double> boundary_values;
0,
boundary_values_u_function,
boundary_values);
void interpolate_boundary_values(const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof, const std::map< types::boundary_id, const Function< spacedim, number > * > &function_map, std::map< types::global_dof_index, number > &boundary_values, const ComponentMask &component_mask=ComponentMask())
The matrix for solve_u() is the same in every time steps, so one could think that it is enough to do this only once at the beginning of the simulation. However, since we need to apply boundary values to the linear system (which eliminate some matrix rows and columns and give contributions to the right hand side), we have to refill the matrix in every time steps before we actually apply boundary data. The actual content is very simple: it is the sum of the mass matrix and a weighted Laplace matrix:
matrix_u.copy_from(mass_matrix);
matrix_u.add(theta * theta * time_step * time_step, laplace_matrix);
matrix_u,
solution_u,
system_rhs);
}
solve_u();
void apply_boundary_values(const std::map< types::global_dof_index, number > &boundary_values, SparseMatrix< number > &matrix, Vector< number > &solution, Vector< number > &right_hand_side, const bool eliminate_columns=true)
Definition: matrix_tools.cc:76
The second step, i.e. solving for $$V^n$$, works similarly, except that this time the matrix on the left is the mass matrix (which we copy again in order to be able to apply boundary conditions, and the right hand side is $$MV^{n-1} - k\left[ \theta A U^n + (1-\theta) AU^{n-1}\right]$$ plus forcing terms. Boundary values are applied in the same way as before, except that now we have to use the BoundaryValuesV class:
laplace_matrix.vmult(system_rhs, solution_u);
system_rhs *= -theta * time_step;
mass_matrix.vmult(tmp, old_solution_v);
system_rhs += tmp;
laplace_matrix.vmult(tmp, old_solution_u);
system_rhs.add(-time_step * (1 - theta), tmp);
system_rhs += forcing_terms;
{
BoundaryValuesV<dim> boundary_values_v_function;
boundary_values_v_function.set_time(time);
std::map<types::global_dof_index, double> boundary_values;
0,
boundary_values_v_function,
boundary_values);
matrix_v.copy_from(mass_matrix);
matrix_v,
solution_v,
system_rhs);
}
solve_v();
Finally, after both solution components have been computed, we output the result, compute the energy in the solution, and go on to the next time step after shifting the present solution into the vectors that hold the solution at the previous time step. Note the function SparseMatrix::matrix_norm_square that can compute $$\left<V^n,MV^n\right>$$ and $$\left<U^n,AU^n\right>$$ in one step, saving us the expense of a temporary vector and several lines of code:
output_results();
std::cout << " Total energy: "
<< (mass_matrix.matrix_norm_square(solution_v) +
laplace_matrix.matrix_norm_square(solution_u)) /
2
<< std::endl;
old_solution_u = solution_u;
old_solution_v = solution_v;
}
}
} // namespace Step23
### The main function
What remains is the main function of the program. There is nothing here that hasn't been shown in several of the previous programs:
int main()
{
try
{
using namespace Step23;
WaveEquation<2> wave_equation_solver;
wave_equation_solver.run();
}
catch (std::exception &exc)
{
std::cerr << std::endl
<< std::endl
<< "----------------------------------------------------"
<< std::endl;
std::cerr << "Exception on processing: " << std::endl
<< exc.what() << std::endl
<< "Aborting!" << std::endl
<< "----------------------------------------------------"
<< std::endl;
return 1;
}
catch (...)
{
std::cerr << std::endl
<< std::endl
<< "----------------------------------------------------"
<< std::endl;
std::cerr << "Unknown exception!" << std::endl
<< "Aborting!" << std::endl
<< "----------------------------------------------------"
<< std::endl;
return 1;
}
return 0;
}
# Results
When the program is run, it produces the following output:
Number of active cells: 16384
Number of degrees of freedom: 16641
Time step 1 at t=0.015625
u-equation: 8 CG iterations.
v-equation: 22 CG iterations.
Total energy: 1.17887
Time step 2 at t=0.03125
u-equation: 8 CG iterations.
v-equation: 20 CG iterations.
Total energy: 2.9655
Time step 3 at t=0.046875
u-equation: 8 CG iterations.
v-equation: 21 CG iterations.
Total energy: 4.33761
Time step 4 at t=0.0625
u-equation: 7 CG iterations.
v-equation: 21 CG iterations.
Total energy: 5.35499
Time step 5 at t=0.078125
u-equation: 7 CG iterations.
v-equation: 21 CG iterations.
Total energy: 6.18652
Time step 6 at t=0.09375
u-equation: 7 CG iterations.
v-equation: 20 CG iterations.
Total energy: 6.6799
...
Time step 31 at t=0.484375
u-equation: 7 CG iterations.
v-equation: 20 CG iterations.
Total energy: 21.9068
Time step 32 at t=0.5
u-equation: 7 CG iterations.
v-equation: 20 CG iterations.
Total energy: 23.3394
Time step 33 at t=0.515625
u-equation: 7 CG iterations.
v-equation: 20 CG iterations.
Total energy: 23.1019
...
Time step 319 at t=4.98438
u-equation: 7 CG iterations.
v-equation: 20 CG iterations.
Total energy: 23.1019
Time step 320 at t=5
u-equation: 7 CG iterations.
v-equation: 20 CG iterations.
Total energy: 23.1019
What we see immediately is that the energy is a constant at least after $$t=\frac 12$$ (until which the boundary source term $$g$$ is nonzero, injecting energy into the system).
In addition to the screen output, the program writes the solution of each time step to an output file. If we process them adequately and paste them into a movie, we get the following:
The movie shows the generated wave nice traveling through the domain and back, being reflected at the clamped boundary. Some numerical noise is trailing the wave, an artifact of a too-large mesh size that can be reduced by reducing the mesh width and the time step.
### Possibilities for extensions
If you want to explore a bit, try out some of the following things:
• Varying $$\theta$$. This gives different time stepping schemes, some of which are stable while others are not. Take a look at how the energy evolves.
• Different initial and boundary conditions, right hand sides.
• More complicated domains or more refined meshes. Remember that the time step needs to be bounded by the mesh width, so changing the mesh should always involve also changing the time step. We will come back to this issue in step-24.
• Variable coefficients: In real media, the wave speed is often variable. In particular, the "real" wave equation in realistic media would read
$\rho(x) \frac{\partial^2 u}{\partial t^2} - \nabla \cdot a(x) \nabla u = f,$
where $$\rho(x)$$ is the density of the material, and $$a(x)$$ is related to the stiffness coefficient. The wave speed is then $$c=\sqrt{a/\rho}$$.
To make such a change, we would have to compute the mass and Laplace matrices with a variable coefficient. Fortunately, this isn't too hard: the functions MatrixCreator::create_laplace_matrix and MatrixCreator::create_mass_matrix have additional default parameters that can be used to pass non-constant coefficient functions to them. The required changes are therefore relatively small. On the other hand, care must be taken again to make sure the time step is within the allowed range.
• In the in-code comments, we discussed the fact that the matrices for solving for $$U^n$$ and $$V^n$$ need to be reset in every time because of boundary conditions, even though the actual content does not change. It is possible to avoid copying by not eliminating columns in the linear systems, which is implemented by appending a false argument to the call:
matrix_u,
solution_u,
system_rhs,
false);
• deal.II being a library that supports adaptive meshes it would of course be nice if this program supported change the mesh every few time steps. Given the structure of the solution — a wave that travels through the domain — it would seem appropriate if we only refined the mesh where the wave currently is, and not simply everywhere. It is intuitively clear that we should be able to save a significant amount of cells this way. (Though upon further thought one realizes that this is really only the case in the initial stages of the simulation. After some time, for wave phenomena, the domain is filled with reflections of the initial wave going in every direction and filling every corner of the domain. At this point, there is in general little one can gain using local mesh refinement.)
To make adaptively changing meshes possible, there are basically two routes. The "correct" way would be to go back to the weak form we get using Rothe's method. For example, the first of the two equations to be solved in each time step looked like this:
\begin{eqnarray*} (u^n,\varphi) + k^2\theta^2(\nabla u^n,\nabla \varphi) &=& (u^{n-1},\varphi) - k^2\theta(1-\theta)(\nabla u^{n-1},\nabla \varphi) + k(v^{n-1},\varphi) + k^2\theta \left[ \theta (f^n,\varphi) + (1-\theta) (f^{n-1},\varphi) \right]. \end{eqnarray*}
Now, note that we solve for $$u^n$$ on mesh $${\mathbb T}^n$$, and consequently the test functions $$\varphi$$ have to be from the space $$V_h^n$$ as well. As discussed in the introduction, terms like $$(u^{n-1},\varphi)$$ then require us to integrate the solution of the previous step (which may have been computed on a different mesh $${\mathbb T}^{n-1}$$) against the test functions of the current mesh, leading to a matrix $$M^{n,n-1}$$. This process of integrating shape functions from different meshes is, at best, awkward. It can be done but because it is difficult to ensure that $${\mathbb T}^{n-1}$$ and $${\mathbb T}^{n}$$ differ by at most one level of refinement, one has to recursively match cells from both meshes. It is feasible to do this, but it leads to lengthy and not entirely obvious code.
The second approach is the following: whenever we change the mesh, we simply interpolate the solution from the last time step on the old mesh to the new mesh, using the SolutionTransfer class. In other words, instead of the equation above, we would solve
\begin{eqnarray*} (u^n,\varphi) + k^2\theta^2(\nabla u^n,\nabla \varphi) &=& (I^n u^{n-1},\varphi) - k^2\theta(1-\theta)(\nabla I^n u^{n-1},\nabla \varphi) + k(I^n v^{n-1},\varphi) + k^2\theta \left[ \theta (f^n,\varphi) + (1-\theta) (f^{n-1},\varphi) \right], \end{eqnarray*}
where $$I^n$$ interpolates a given function onto mesh $${\mathbb T}^n$$. This is a much simpler approach because, in each time step, we no longer have to worry whether $$u^{n-1},v^{n-1}$$ were computed on the same mesh as we are using now or on a different mesh. Consequently, the only changes to the code necessary are the addition of a function that computes the error, marks cells for refinement, sets up a SolutionTransfer object, transfers the solution to the new mesh, and rebuilds matrices and right hand side vectors on the new mesh. Neither the functions building the matrices and right hand sides, nor the solvers need to be changed.
While this second approach is, strictly speaking, not quite correct in the Rothe framework (it introduces an addition source of error, namely the interpolation), it is nevertheless what almost everyone solving time dependent equations does. We will use this method in step-31, for example.
# The plain program
/* ---------------------------------------------------------------------
*
* Copyright (C) 2006 - 2020 by the deal.II authors
*
* This file is part of the deal.II library.
*
* The deal.II library is free software; you can use it, redistribute
* it, and/or modify it under the terms of the GNU Lesser General
* version 2.1 of the License, or (at your option) any later version.
* The full text of the license can be found in the file LICENSE.md at
* the top level directory of deal.II.
*
* ---------------------------------------------------------------------
*
* Author: Wolfgang Bangerth, Texas A&M University, 2006
*/
#include <fstream>
#include <iostream>
namespace Step23
{
using namespace dealii;
template <int dim>
class WaveEquation
{
public:
WaveEquation();
void run();
private:
void setup_system();
void solve_u();
void solve_v();
void output_results() const;
DoFHandler<dim> dof_handler;
SparsityPattern sparsity_pattern;
SparseMatrix<double> laplace_matrix;
Vector<double> solution_u, solution_v;
Vector<double> old_solution_u, old_solution_v;
Vector<double> system_rhs;
double time_step;
double time;
unsigned int timestep_number;
const double theta;
};
template <int dim>
class InitialValuesU : public Function<dim>
{
public:
virtual double value(const Point<dim> & /*p*/,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
return 0;
}
};
template <int dim>
class InitialValuesV : public Function<dim>
{
public:
virtual double value(const Point<dim> & /*p*/,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
return 0;
}
};
template <int dim>
class RightHandSide : public Function<dim>
{
public:
virtual double value(const Point<dim> & /*p*/,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
return 0;
}
};
template <int dim>
class BoundaryValuesU : public Function<dim>
{
public:
virtual double value(const Point<dim> & p,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
if ((this->get_time() <= 0.5) && (p[0] < 0) && (p[1] < 1. / 3) &&
(p[1] > -1. / 3))
return std::sin(this->get_time() * 4 * numbers::PI);
else
return 0;
}
};
template <int dim>
class BoundaryValuesV : public Function<dim>
{
public:
virtual double value(const Point<dim> & p,
const unsigned int component = 0) const override
{
(void)component;
Assert(component == 0, ExcIndexRange(component, 0, 1));
if ((this->get_time() <= 0.5) && (p[0] < 0) && (p[1] < 1. / 3) &&
(p[1] > -1. / 3))
return (std::cos(this->get_time() * 4 * numbers::PI) * 4 * numbers::PI);
else
return 0;
}
};
template <int dim>
WaveEquation<dim>::WaveEquation()
: fe(1)
, dof_handler(triangulation)
, time_step(1. / 64)
, time(time_step)
, timestep_number(1)
, theta(0.5)
{}
template <int dim>
void WaveEquation<dim>::setup_system()
{
triangulation.refine_global(7);
std::cout << "Number of active cells: " << triangulation.n_active_cells()
<< std::endl;
dof_handler.distribute_dofs(fe);
std::cout << "Number of degrees of freedom: " << dof_handler.n_dofs()
<< std::endl
<< std::endl;
DynamicSparsityPattern dsp(dof_handler.n_dofs(), dof_handler.n_dofs());
sparsity_pattern.copy_from(dsp);
mass_matrix.reinit(sparsity_pattern);
laplace_matrix.reinit(sparsity_pattern);
matrix_u.reinit(sparsity_pattern);
matrix_v.reinit(sparsity_pattern);
QGauss<dim>(fe.degree + 1),
QGauss<dim>(fe.degree + 1),
laplace_matrix);
solution_u.reinit(dof_handler.n_dofs());
solution_v.reinit(dof_handler.n_dofs());
old_solution_u.reinit(dof_handler.n_dofs());
old_solution_v.reinit(dof_handler.n_dofs());
system_rhs.reinit(dof_handler.n_dofs());
constraints.close();
}
template <int dim>
void WaveEquation<dim>::solve_u()
{
SolverControl solver_control(1000, 1e-8 * system_rhs.l2_norm());
SolverCG<Vector<double>> cg(solver_control);
cg.solve(matrix_u, solution_u, system_rhs, PreconditionIdentity());
std::cout << " u-equation: " << solver_control.last_step()
<< " CG iterations." << std::endl;
}
template <int dim>
void WaveEquation<dim>::solve_v()
{
SolverControl solver_control(1000, 1e-8 * system_rhs.l2_norm());
SolverCG<Vector<double>> cg(solver_control);
cg.solve(matrix_v, solution_v, system_rhs, PreconditionIdentity());
std::cout << " v-equation: " << solver_control.last_step()
<< " CG iterations." << std::endl;
}
template <int dim>
void WaveEquation<dim>::output_results() const
{
DataOut<dim> data_out;
data_out.attach_dof_handler(dof_handler);
data_out.build_patches();
const std::string filename =
"solution-" + Utilities::int_to_string(timestep_number, 3) + ".vtu";
data_out.set_flags(vtk_flags);
std::ofstream output(filename);
data_out.write_vtu(output);
}
template <int dim>
{
setup_system();
VectorTools::project(dof_handler,
constraints,
QGauss<dim>(fe.degree + 1),
InitialValuesU<dim>(),
old_solution_u);
VectorTools::project(dof_handler,
constraints,
QGauss<dim>(fe.degree + 1),
InitialValuesV<dim>(),
old_solution_v);
Vector<double> tmp(solution_u.size());
Vector<double> forcing_terms(solution_u.size());
for (; time <= 5; time += time_step, ++timestep_number)
{
std::cout << "Time step " << timestep_number << " at t=" << time
<< std::endl;
mass_matrix.vmult(system_rhs, old_solution_u);
mass_matrix.vmult(tmp, old_solution_v);
laplace_matrix.vmult(tmp, old_solution_u);
system_rhs.add(-theta * (1 - theta) * time_step * time_step, tmp);
RightHandSide<dim> rhs_function;
rhs_function.set_time(time);
QGauss<dim>(fe.degree + 1),
rhs_function,
tmp);
forcing_terms = tmp;
forcing_terms *= theta * time_step;
rhs_function.set_time(time - time_step);
QGauss<dim>(fe.degree + 1),
rhs_function,
tmp);
forcing_terms.add((1 - theta) * time_step, tmp);
{
BoundaryValuesU<dim> boundary_values_u_function;
boundary_values_u_function.set_time(time);
std::map<types::global_dof_index, double> boundary_values;
0,
boundary_values_u_function,
boundary_values);
matrix_u.copy_from(mass_matrix);
matrix_u.add(theta * theta * time_step * time_step, laplace_matrix);
matrix_u,
solution_u,
system_rhs);
}
solve_u();
laplace_matrix.vmult(system_rhs, solution_u);
system_rhs *= -theta * time_step;
mass_matrix.vmult(tmp, old_solution_v);
system_rhs += tmp;
laplace_matrix.vmult(tmp, old_solution_u);
system_rhs.add(-time_step * (1 - theta), tmp);
system_rhs += forcing_terms;
{
BoundaryValuesV<dim> boundary_values_v_function;
boundary_values_v_function.set_time(time);
std::map<types::global_dof_index, double> boundary_values;
0,
boundary_values_v_function,
boundary_values);
matrix_v.copy_from(mass_matrix);
matrix_v,
solution_v,
system_rhs);
}
solve_v();
output_results();
std::cout << " Total energy: "
<< (mass_matrix.matrix_norm_square(solution_v) +
laplace_matrix.matrix_norm_square(solution_u)) /
2
<< std::endl;
old_solution_u = solution_u;
old_solution_v = solution_v;
}
}
} // namespace Step23
int main()
{
try
{
using namespace Step23;
WaveEquation<2> wave_equation_solver;
wave_equation_solver.run();
}
catch (std::exception &exc)
{
std::cerr << std::endl
<< std::endl
<< "----------------------------------------------------"
<< std::endl;
std::cerr << "Exception on processing: " << std::endl
<< exc.what() << std::endl
<< "Aborting!" << std::endl
<< "----------------------------------------------------"
<< std::endl;
return 1;
}
catch (...)
{
std::cerr << std::endl
<< std::endl
<< "----------------------------------------------------"
<< std::endl;
std::cerr << "Unknown exception!" << std::endl
<< "Aborting!" << std::endl
<< "----------------------------------------------------"
<< std::endl;
return 1;
}
return 0;
}
std::string get_time()
Definition: utilities.cc:1016 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.933013379573822, "perplexity": 1834.1866167293285}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500671.13/warc/CC-MAIN-20230208024856-20230208054856-00143.warc.gz"} |
https://www.physicsforums.com/threads/electricity-and-resistance-question.4599/ | Electricity and resistance Question
1. Aug 7, 2003
PerpetuallyFrustrate
A bird stands on a electric transmission line carring 2500 A. The line has .000025 ohms resistance per meter and the bird's feet are 4 cm apart. What voltage does the bird feel?
I know R = p L/A, but how do i figure out the area. Also do I use 4 cm as the length?
2. Aug 7, 2003
HInt
Could you figure the voltage if the bird had its feet 1 meter apart?
3. Aug 7, 2003
PerpetuallyFrustrate
No
I dont understand whether the 4 cm is the L and if so then what is the area?
4. Aug 8, 2003
futz
If you know the resistance per meter (0.000025) and the number of meters (0.04) their product should give you the total resistance in the 4 cm length. Knowing the current, it should be a staightforward use of Ohm's Law to get the voltage across that section of the wire. I'm not sure why you would need to use the area at all.
Similar Discussions: Electricity and resistance Question | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8600179553031921, "perplexity": 1249.2494586628404}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-22/segments/1495463608617.6/warc/CC-MAIN-20170525214603-20170525234603-00456.warc.gz"} |
https://curriculum.illustrativemathematics.org/HS/students/2/1/16/index.html | # Lesson 16
More Symmetry
Let’s describe more symmetries of shapes.
### 16.1: Which One Doesn't Belong: Symmetry
Which one doesn’t belong?
### 16.2: Self Rotation
Determine all the angles of rotation that create symmetry for the shape your teacher assigns you. Create a visual display about your shape. Include these parts in your display:
• the name of your shape
• the definition of your shape
• drawings of each rotation that creates symmetry
• a description in words of each rotation that creates symmetry, including the center, angle, and direction of rotation
• one non-example (a description and drawing of a rotation that does not result in symmetry)
Finite figures, like the shapes we have looked at in class, cannot have translation symmetry. But with a pattern that continues on forever, it is possible. Patterns like this one that have translation symmetry in only one direction are called frieze patterns.
1. What are the lines of symmetry for this pattern?
2. What angles of rotation produce symmetry for this pattern?
3. What translations produce symmetry for this pattern if we imagine it extending horizontally forever?
### 16.3: Parallelogram Symmetry
Clare says, "Last class I thought the parallelogram would have reflection symmetry. I tried using a diagonal as the line of symmetry but it didn’t work. So now I’m doubting that it has rotation symmetry."
Lin says, "I thought that too at first, but now I think that a parallelogram does have rotation symmetry. Here, look at this."
How could Lin describe to Clare the symmetry she sees?
### Summary
A shape has rotation symmetry if there is a rotation between 0 and 360 degrees that takes the shape to itself. A regular hexagon has many angles that work to create rotation symmetry. Here is one of them. What other angles would create a rotation where the image is the same as the original figure?
Can you think of a shape that has translation symmetry?
There aren’t any polygons with translation symmetry, but an infinite shape like a line can be translated such that the translation takes the line to itself.
### Glossary Entries
• assertion
A statement that you think is true but have not yet proved.
• congruent
One figure is called congruent to another figure if there is a sequence of translations, rotations, and reflections that takes the first figure onto the second.
• directed line segment
A line segment with an arrow at one end specifying a direction.
• image
If a transformation takes $$A$$ to $$A'$$, then $$A$$ is the original and $$A'$$ is the image.
• line of symmetry
A line of symmetry for a figure is a line such that reflection across the line takes the figure onto itself.
The figure shows two lines of symmetry for a regular hexagon, and two lines of symmetry for the letter I.
• reflection
A reflection is defined using a line. It takes a point to another point that is the same distance from the given line, is on the other side of the given line, and so that the segment from the original point to the image is perpendicular to the given line.
In the figure, $$A'$$ is the image of $$A$$ under the reflection across the line $$m$$.
• reflection symmetry
A figure has reflection symmetry if there is a reflection that takes the figure to itself.
• rigid transformation
A rigid transformation is a translation, rotation, or reflection. We sometimes also use the term to refer to a sequence of these.
• rotation
A rotation has a center and a directed angle. It takes a point to another point on the circle through the original point with the given center. The 2 radii to the original point and the image make the given angle.
$$P'$$ is the image of $$P$$ after a counterclockwise rotation of $$t^\circ$$ using the point $$O$$ as the center.
Quadrilateral $$ABCD$$ is rotated 120 degrees counterclockwise using the point $$D$$ as the center.
• rotation symmetry
A figure has rotation symmetry if there is a rotation that takes the figure onto itself. (We don't count rotations using angles such as $$0^\circ$$ and $$360^\circ$$ that leave every point on the figure where it is.)
• symmetry
A figure has symmetry if there is a rigid transformation which takes it onto itself (not counting a transformation that leaves every point where it is).
• theorem
A statement that has been proved mathematically.
• translation
A translation is defined using a directed line segment. It takes a point to another point so that the directed line segment from the original point to the image is parallel to the given line segment and has the same length and direction.
In the figure, $$A'$$ is the image of $$A$$ under the translation given by the directed line segment $$t$$. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7307801246643066, "perplexity": 751.5266380094207}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243991737.39/warc/CC-MAIN-20210514025740-20210514055740-00061.warc.gz"} |
http://mathematica.stackexchange.com/questions/36812/add-brackets-to-a-string-list | # Add Brackets to a string list
Hello stackexchange community!
I have a stringlist with a value and his error for eg:
{{"12","1"},{"13","2"}}
Now i want to output this as something like this (for a lab-report):
{"12(1)","13(2)"}
Unfortunately I have no idea how to get this working...
Cx
-
Your first list as pasted does not contain strings, but integers. Could you clarify? – Yves Klett Nov 11 '13 at 13:09
sorry, i corrected the error now – cxkoda Nov 11 '13 at 13:21
now I solved it like this: errformat[list_] := Table[StringJoin[ToString[list[[i, 1]]], "(", ToString[list[[i, 2]]], ")"], {i, 1, Dimensions[list][[1]]}] – cxkoda Nov 11 '13 at 13:32
thanks for your tipps – cxkoda Nov 11 '13 at 13:33
I would recommend Chris solution, which is clean&instructive. BTW, try Length[list]. – Yves Klett Nov 11 '13 at 13:35
Using Apply:
StringJoin[#1, "(", #2, ")"] & @@@ {{"12", "1"}, {"13", "2"}}
{"12(1)", "13(2)"}
-
Cleaner than mine :-) – Yves Klett Nov 11 '13 at 13:34
Depending on what you intend to do with the output you may also use StringForm:
StringForm["()", ##] & @@@ {{"12", "1"}, {"13", "2"}}
{12(1),13(2)}
Internally this remains as a StringForm expression which may be good or bad given the circumstance.
-
Or with a pattern:
{{"12", "1"}, {"13", "2"}} /. {a_String, b_String} :> StringJoin[a, "(", b, ")"]
-
ToString[#[[1]]] <> "(" <> ToString[#[[2]]] <> ")" & /@ {{12,1}, {13, 2}}
Edit: with all elements as strings, you can dump ToString:
#[[1]] <> "(" <> #[[2]] <> ")" & /@ {{"12", "1"}, {"13", "2"}}
` | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2351449429988861, "perplexity": 19819.283808388947}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1414637898644.9/warc/CC-MAIN-20141030025818-00157-ip-10-16-133-185.ec2.internal.warc.gz"} |
https://artofproblemsolving.com/wiki/index.php/2009_AMC_12A_Problems/Problem_12 | # 2009 AMC 12A Problems/Problem 12
## Problem
How many positive integers less than are times the sum of their digits?
## Solution
### Solution 1
The sum of the digits is at most . Therefore the number is at most . Out of the numbers to the one with the largest sum of digits is , and the sum is . Hence the sum of digits will be at most .
Also, each number with this property is divisible by , therefore it is divisible by , and thus also its sum of digits is divisible by . Thus, the number is divisible by .
We only have six possibilities left for the sum of the digits: , , , , , and , but since the number is divisible by , the digits can only add to or . This leads to the integers , , , , , and being possibilities. We can check to see that solution: the number is the only solution that satisfies the conditions in the problem.
### Solution 2
We can write each integer between and inclusive as where and . The sum of digits of this number is , hence we get the equation . This simplifies to . Clearly for there are no solutions, hence and we get the equation . This obviously has only one valid solution , hence the only solution is the number .
### Solution 3
The sum of the digits is at most . Therefore the number is at most . Since the number is times the sum of its digits, it must be divisible by , therefore also by , therefore the sum of its digits must be divisible by . With this in mind we can conclude that the number must be divisible by , not just by . Since the number is divisible by , it is also divisible by , therefore the sum of its digits is divisible by , therefore the number is divisible by , which leaves us with , and . Only is times its digits, hence the answer is . | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9738010764122009, "perplexity": 171.2267948753141}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703581888.64/warc/CC-MAIN-20210125123120-20210125153120-00410.warc.gz"} |
https://www.physicsforums.com/threads/parabolic-cylinder-line-integral.231358/ | Parabolic Cylinder line integral
1. Apr 26, 2008
christopnz
1.The problem statement, all variables and given/known data
(Parabolic Cylinder) find the area of the surface extending upward form x^2 + y^2 =1 to z = 1 - x^2 using line integral
2.
Could some one please outline the method to solving this. I tryed using spherical corridinates but am unsure if this was correcect
3. The attempt at a solution
Last edited: Apr 26, 2008
2. Apr 26, 2008
HallsofIvy
Staff Emeritus
Surely, since this is a cylinder, cylindrical coordinates would be better? That is, use polar coordinates for two coordinates, z for the third. $x= r cos(\theta)$, $y= r sin(\theta)$ so you will be integrating $z= 1- x^2= 1- r^2 cos^2(\theta)$ over the unit circle.
3. Apr 26, 2008
christopnz
ty that helped alot
Similar Discussions: Parabolic Cylinder line integral | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9829309582710266, "perplexity": 1657.8562737481452}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-51/segments/1512948530668.28/warc/CC-MAIN-20171213182224-20171213202224-00493.warc.gz"} |
https://socratic.org/questions/given-any-sinusoidal-equation-how-do-you-identify-the-type-of-transformations-th | Trigonometry
Topics
# Given any sinusoidal equation, how do you identify the type of transformations that are made?
Mar 12, 2018
Example: Describe the transformations to get $g \left(x\right) = 2 \sin \left(3 \left(x + \frac{\pi}{4}\right)\right) + 2$ from $f \left(x\right) = \sin x$
Here are what each of the parameters in the equation $y = a \sin \left(b \left(x - c\right)\right) + d$:
$a \to$ vertical stretch
$\frac{1}{b} \to$horizontal stretch
$c \to$ phase shift
$d \to$vertical transformation
So in the given equation, we have a vertical stretch by a factor of $2$, a horizontal stretch by a factor of $\frac{1}{3}$, a transformation $\frac{\pi}{4}$ units left and a transformation $2$ units up.
Hopefully this helps!
##### Impact of this question
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https://blog.r6l7.com/tag/sysadmin/ | Well, that was an ordeal. It took the better part of a week, but I have a server again. This blogging platform was not part of » | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8259883522987366, "perplexity": 980.5060425498991}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-26/segments/1560627998238.28/warc/CC-MAIN-20190616122738-20190616144738-00295.warc.gz"} |
http://mathhelpforum.com/pre-calculus/17976-linear-programming-using-graphs.html | # Math Help - Linear Programming using graphs
1. ## Linear Programming using graphs
a) Use graphical methods to determine the feasible region for these constraints:
Subject to 2x1+5x2 is greater than or equal to 10
2x1 - x2 is less than or equal to 6
x1 is greater than or equal to 1
x1 + x2 is less or equal to 6
(the 1 & 2 after the x is small which sits just below the x)
b) subject to the constraints in a),
i) minimise P=x2
ii) maximise Q=10x1 + 5x2
2. This is good for practice.
It will be long if I show it all, so let me assume you know how to graph inequalities and how to find the intersection of two inequalities.
I don't know how to sketch figures here so sketch it on paper.
Subject to 2x1+5x2 is greater than or equal to 10
The x1 and x2 will confuse you no end, so let x = x1, and y = x2.
So the four constraints are:
2x +5y >= 10 -------(1)
2x -y <= 6 ----------(2)
x >= 1 --------------(3)
x +y <= 6 -----------(4)
Plot the 4 inequalities on the same x,y rectangular axes.
You'd find that the feasible region is a quadrilateral whose four corner points are
(1,1.6) .......or (1,8/5)
(1,5)
(4,2)
(2.67,0.67)....or (8/3,2/3)
i) minimise P=x2
Or, minimize P = y.
The corner point with the lowest y is (8/3,2/3).
Therefore, minimum P = 2/3 --------------------------answer.
ii) maximise Q=10x1 + 5x2
Or, maximize Q = 10x +5y -------------**
You have to test that to all of the 4 corner points to see which corner gives the highest Q.
----at (1,8/5)---- Q = 10(1) +5(8/5) = 18
----at (1,5)------ Q = 10(1) +5(5) = 35
----at (4,2)------ Q = 10(4) +5(2) = 50
----at (8/3,2/3)-- Q = 10(8/3) +5(2/3) = 90/3 = 30
Therefore, maximum Q is 50. -------------------------answer.
If anything is not clear, ask me.
3. Hello, tondie2!
Use graphical methods to determine the feasible region for these constraints:
. . $\begin{array}{cc}2x+5y \:\geq\:10 & [1] \\
2x - y \:\leq \:6 & [2]\\
x + y \:\leq\:6 & [3]\\
x \:\geq \:1 & [4]\end{array}$
Graph the line of [1].
It has intercepts: $(5,0),\;(0,2)$
Shade the region above the line.
Graph the line of [2].
It has intercepts: $(3,0),\;(0,-6)$
Shade the region above the line.
Graph the line of [3].
It has intercepts: $(6,0),\;(0,6)$
Shade the region below the line.
Graph the line of [4].
It is a vertical line with x-intercept $(1,0)$.
Shade the region to the right of the line.
As ticbol pointed out, the region is a quadrilateral.
. .
But I differ on one vertex.
$[1] \cap [2]\!:\;\left(\frac{10}{3},\,\frac{2}{3}\right)$
$[1] \cap [4]\!:\;\left(1,\,\frac{8}{5}\right)$
$[2] \cap [3]\!:\;(4,\,2)$
$[3] \cap [4]\!:\;(1,\,5)$
4. Originally Posted by ticbol
This is good for practice.
It will be long if I show it all, so let me assume you know how to graph inequalities and how to find the intersection of two inequalities.
I don't know how to sketch figures here so sketch it on paper.
Originally Posted by Soroban
As ticbol pointed out, the region is a quadrilateral.
But I differ on one vertex.
$[1] \cap [2]\!:\;\left(\frac{10}{3},\,\frac{2}{3}\right)$
$[1] \cap [4]\!:\;\left(1,\,\frac{8}{5}\right)$
$[2] \cap [3]\!:\;(4,\,2)$
$[3] \cap [4]\!:\;(1,\,5)$
If you want to draw graphs badly enough, the picture environment isn't too awful. Here is the quadrilateral.
$\setlength{\unitlength}{1cm}
\begin{picture}(4,4)
\qbezier(3.33,.667)(3.33,.667)(1,1.6)
\qbezier(4,2)(4,2)(3.33,.667)
\qbezier(4,2)(4,2)(1,5)
\qbezier(1,1.6)(1,1.6)(1,5)
\qbezier(0,0)(0,0)(4,0)
\qbezier(0,0)(0,0)(0,5)
\end{picture}
$
Below is the LaTeX code. I have something like this stored in a document. I cut and pasted it here and then modified it.
The lines are drawn by qbezier. \qbezier(X,Y)(X,Y)(V,W) draws a line beteen points (X,Y) and (V,W). Note the (X,Y) is repeated. You could also repeat the (V,W) with same effect and the order of the points does not matter.
The \setlength, \begin{picture} and \end{picture} commands are just a little housekeeping that needs to be done. The (4,4) in \begin{picture} sets the size of the axes. The \setlength sets the size of the picture. If LaTeX complains about the size of the image, reduce the length.
Code:
\setlength{\unitlength}{1cm}
\begin{picture}(4,4)
\qbezier(3.33,.667)(3.33,.667)(1,1.6)
\qbezier(4,2)(4,2)(3.33,.667)
\qbezier(4,2)(4,2)(1,5)
\qbezier(1,1.6)(1,1.6)(1,5)
\qbezier(0,0)(0,0)(4,0)
\qbezier(0,0)(0,0)(0,5)
\end{picture}
The first 4 qbeziers draw the quadrilateral. I just put the coordinates in straight from Soroban's post. The second 2 qbeziers draw the axes. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 14, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8385932445526123, "perplexity": 2109.190080188846}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-27/segments/1435375098685.20/warc/CC-MAIN-20150627031818-00250-ip-10-179-60-89.ec2.internal.warc.gz"} |
https://gasstationwithoutpumps.wordpress.com/2017/06/23/uncompensated-transimpedance-amplifier/ | Gas station without pumps
2017 June 23
Uncompensated transimpedance amplifier
Filed under: Circuits course — gasstationwithoutpumps @ 16:07
Tags:
In my book Applied Electronics for Bioengineers, I have students build transimpedance amplifiers for phototransistors (and some students use them for electret microphones as well). In the book, I never deal with compensating the transimpedance amplifiers to avoid oscillation, as I try to stay away from students having to reason about phase of signals and oscillation has never been a problem in the student designs.
But I thought that I ought to understand the method myself, especially if I need to help students trying to do higher bandwidth, higher gain transimpedance amplifiers. First I read up on the subject—one of the better introductions is the Maxim application note 5129 Stabilize your transimpedance amplifier. The key concepts are the following:
• When the frequency is high enough (where the open-loop gain is limited by the gain-bandwidth product) the phase change of the amplifier is about –90° (or 90° for the negative input).
• If we set up a transimpedance amplifier with feedback resistor R, then the feedback consists of a low-pass RC filter: a voltage divider with R on tap and the input capacitance of the amplifier and any capacitance in parallel with the current source on the bottom.
• The phase change of a low-pass RC filter (gain $\frac{1}{1+j\omega RC}$) approaches –90° above the corner frequency.
• Having a phase change of 0° and gain ≥ 1 around a feedback loop results in instability and possible oscillation.
That means that we can have instability at frequencies between $\frac{1}{2\pi RC}$ and the gain-bandwidth product (though we probably only have problems for frequencies at least a factor of 3 above the low-pass corner frequency, since the phase change of the filter is only asymptotically –90°). If the parasitic capacitances are low and we only request small transimpedance gain, then RC is small, and the corner frequency of the low-pass filter is above the gain-bandwidth product, so there are no problems. Will the students ever encounter problems?
Today I tried to make an unstable transimpedance amplifier using the MCP6004 op amps that we use in class. The op amps have a gain-bandwidth product of 1MHz, so I needed an RC time constant much larger than 160ns. I chose 2MΩ and 47nF for an RC time constant of 94 ms and a corner frequency of 1.69Hz.
The very large bypass capacitors are to make sure that there are no sneak paths through the power supply and positive input—to make sure that I’m looking at the phenomenon I’m really interested in.
I connected the amplifier up to the Analog Discovery 2, and I definitely got instability:
There does seem to be a somewhat unstable oscillation happening.
The reasoning about the amplifier instability suggests that the oscillation should be at about the frequency where the gain around the loop is 1, that is where $\frac{f_{GBW}}{f}\frac{1}{2\pi f RC}=1$ or $f= \sqrt{\frac{f_{GBW}}{2\pi RC}}$. For the circuit I made, that would be around $\sqrt{1MHz \; 1.69Hz}= 1.3kHz$.
I did some FFTs of the waveform (averaging over hundreds of traces to reduce noise, since the signal is fluctuating).
The peak is around 1380Hz, very close to the predicted oscillation frequency. Also visible are harmonics of 60Hz, which are the correct output of the transimpedance amplifier (picking up stray currents by capacitive coupling).
To compensate a transimpedance amplifier, we need to add a small capacitor in parallel with the feedback resistor, making the gain of the feedback filter $\frac{1+j\omega R_{F}C_{F}}{1+j\omega R_{F}(C_{F}+C_{i})}$, where $R_{F}$ and $C_{F}$ are the feedback components and $C_{i}$ is the input capacitance. For “optimal” compensation, we want to set the upper corner frequency $1/(2\pi R_{F}C_{F})$ at the geometric mean of the lower corner frequency $1/(2\pi R_{F}(C_{F} + C_{i}))$ and the gain-bandwidth product $f_{GBW}$. Using a larger capacitor (overcompensating) increases the phase margin (thus allowing for some variation from specs) at the cost of reducing the bandwidth of the final amplifier.
We can set the equation up as $1/(2\pi R_{F}C_{F})^2 = f_{GBW}/(2\pi R_{F}(C_{F} + C_{i}))$, which we can simplify by assuming that $C_{i} \gg C_{F}$ to get $C_{F} = \sqrt{ \frac{C_{i}}{2 \pi R_{F}f_{GBW}}}$, which for my design comes to 61pF.
A 68pF compensation capacitor cuts out the oscillation peak, but there is still a fair amount of noise around the corner frequency of the amplifier (1.2kHz). Overcompensating with a 680pF capacitor reduces the noise substantially, but the bandwidth is reduced to 120Hz.
I also tried a somewhat more realistic example, with only a 2.2nF input capacitance, which calls for about a 13pF compensation capacitor. A 20pF capacitor does fine:
The oscillation is well suppressed by the compensation capacitor.
Now I have to decide how much (if any) of this to include in my book. Perhaps it can be an optional “advanced” section in the transimpedance amplifier chapter? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 15, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8585023283958435, "perplexity": 1216.891111623607}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891814700.55/warc/CC-MAIN-20180223115053-20180223135053-00211.warc.gz"} |
http://mathhelpforum.com/calculus/72697-integration-question.html | # Math Help - Integration Question
1. ## Integration Question
The Integral of $1/
(2x+3)$
I am wondering if I could pull out the 2 from the denominator? So, I'd end up with $1/(2(x+3/2))$ Then could I just do 1/2 the integral of $1/(x+(3/2))$ which is ln(x + 3/2)? so the answer would be 1/2 LN(x+ 3/2)?
Is there a better way, or a correct way to solve this?
Thank you
2. Just put $u=2x+3$ and you'll arrive at $\frac12\int\frac{du}u=\frac12\ln|u|+k.$ Just back-substitute. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 5, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9854274988174438, "perplexity": 639.1482485854813}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-35/segments/1408500829210.91/warc/CC-MAIN-20140820021349-00046-ip-10-180-136-8.ec2.internal.warc.gz"} |
http://utau.wikia.com/wiki/User_blog:BunnyMMD11 | # BunnyMMD11
My favorite wikis
• I live in Dominican Republic
• I was born on September 11
• My occupation is Digital Artist and Dancer
• I am Female
• ## UTAU Wakane Zuzu.
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• ## (UTAU) Wakane Zuzu (School Uniform)
June 21, 2014 by BunnyMMD11
Here's My School Version Of My UTAU :3
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• ## Wakane Zuzu
June 20, 2014 by BunnyMMD11
So... Here She Is, My UTAU: Wakane Zuzu! \(^.^)/
And, Here or here You can see the videos of Zuzu,
Hope You Like It! | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9500757455825806, "perplexity": 1041.165238270209}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917122720.81/warc/CC-MAIN-20170423031202-00395-ip-10-145-167-34.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/integral-of-xsinx-2.345081/ | # Integral of (xsinx)^2?
1. Oct 12, 2009
### emin
hi all,
I've been trying to integrate this thing for ages.i tried using integration by parts using u=x^2,
dv/dx=sin^2 x but it just doesn't seem to end.any help or pointers much appreciated.
thanks
2. Oct 12, 2009
### VeeEight
Switch your u=.. and dv=.. around.
Another method would be to try an identity, such as the double angle identity for your (sinx)^2
3. Oct 12, 2009
### emin
hmm i hadn't thought of the identity, i'll give it a go.
thanks.
4. Oct 12, 2009
### n!kofeyn
I would use your original u-substitution (u=x2), and then use the half-angle formula for sin2x to integrate the dv. Then after you complete the integration by parts the first time, you'll get a sum of two functions in the integral term. One of them you'll be able to immediately integrate, while for the other one you can use integration by parts again.
5. Oct 13, 2009
### emin
i managed to integrate it but i think i may ave made an error.
heres the result:
x^3/4-x^2/2sin2x-x/2cos2x-sin2x/4
don't know how to put it in proper formulae.
anyway thanks for the help.
6. Oct 13, 2009
### TheoMcCloskey
emin - I come up with a slightly different answer. Can you provide details of your solution. The starting approach I took is as follows:
$$I = \int x^2 \cdot \sin^2(x)\,dx = \int x^2 \cdot \frac{(1-\cos(2x))}{2} \, dx$$
then let
$$2I = \int x^2 \cdot (1-\cos(2x)) \, dx = \frac{x^3}{3} - I_2$$
where
$$I_2 = \int x^2 \cdot \cos(2x) \, dx = \int \left (\frac{2x}{2} \right )^2 \cdot \cos(2x) \, d\left ( \frac{2x}{2} \right ) = (1/8) \int s^2 \cdot \cos(s) \, ds$$
where $s=2x$
7. Oct 13, 2009
### emin
i did get my fractions mixed didn't i?
i was doing it on an a4 page and got all the working jumbled.
yes that is the approach i took, i should be able to run it through mathematica when i get the chance, and see what answer it comes up with.
Similar Discussions: Integral of (xsinx)^2? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9438380002975464, "perplexity": 1311.9636642910596}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886109525.95/warc/CC-MAIN-20170821191703-20170821211703-00292.warc.gz"} |
http://blog.selfshadow.com/2018/08/05/multi-faceted-part-3/ | # A Multi-Faceted Exploration (Part 3)
## A New Dimension
In the last post, I’d shown how a small tweak to Imageworks’ multiple-scattering Fresnel term, $\color{brown}{F_\mathrm{ms}}$, brought their approximation closer to the reference solution of Heitz et al. However, there was still a niggling difference at high roughness, most noticeable under uniform lighting:
Figure 1: Furnace test, with roughness $\in [\frac{1}{8}, \frac{2}{8}, \ldots 1]$ (left halves: Imageworks, right halves: Heitz).
At the end of the day, $\color{brown}{F_\mathrm{ms}}$ is based on a simple diffuse model, and its limitations become more apparent as multiple scattering increases with roughness.
A more accurate alternative would be to precalculate a multiple-scattering directional albedo LUT that incorporates Fresnel, directly from the Heitz model. This new term, which I’ll call $\color{teal}{E_\mathrm{Fms}}$, leads to the following minor change to the multiple-scattering lobe:
The good news is that this version produces results that match Heitz in a furnace environment:
Figure 2: Furnace test, with roughness $\in [\frac{1}{8}, \frac{2}{8}, \ldots 1]$ (left halves: with $\Ems$, right halves: Heitz).
The bad news is that we need a 3D LUT for $\Ems$, since it depends not only on the view angle ($\mu_o$) and roughness, but also $\Fr$ (or specular reflectance). Worse, for coloured metals – such as our lovely copper example – we’d need to do three separate 3D lookups for R, G and B. The only silver lining is that this cost can potentially be amortised across lights, but it’s still less than ideal for real-time applications.
Note: a secondary concern is that this change also breaks the recipriocity of the multiple-scattering model, since the results will be different if $\mu_o$ and $\mu_i$ are swapped. While this isn’t a practical issue for real-time rendering, it could be a problem in other contexts (e.g. bidirectional path tracing).
## Schlick Alternative
If we’re willing to restrict ourselves to Schlick’s Fresnel approximation1, then we can adapt a popular approach that’s been used with environmental lighting in games for a number of years [Drobot 2013; Karis 2013; Lazarov 2013]. In this context, the roughness and directional-dependent effects of microfacet shadowing and Fresnel reflection are factored out and preintegrated ahead of time for a given BRDF. At run time, this term is combined with separately prefiltered environmental maps to produce a cheap but effective approximation of the real integral of the BRDF and the lighting.
This idea goes back further (see the Ambient BRDF of [Gotanda 2010]), but the newer variants more compact as they exploit the linearity of Schlick Fresnel, $\Fs$, to factor out $\Fr$, which reduces the dimensionality of the preintegrated table (or fit, in the case of [Lazarov 2013]). I’ll quickly recap how this works, as it naturally extends to a solution for $\Ems$.
What these approaches are effectively calculating is a version of the single-scattering directional albedo, $\E$, that incorporates $\Fs$. Let’s call this $\Ess$:
The key observation is that Schlick Fresnel’s additive form
allows $\Ess$ to be split into two parts:
one that will be tinted by $\Fr$ of the material at run time, and another that’s left untinted. This means that we can precompute a 2D LUT containing these two terms, rather than needing a 3D LUT.
A little more formally, we can view this as decomposing $\E$ into two factors, $\wa$ and $\wb$:
which are then multiplied by two orders of $\Fr$ and summed to form $\Ess$:
Apologies if I have laboured the point, but hopefully you can see where this is going: we can do a similar decomposition with the multiple-scattering albedo, $1 - \E$.
This time I’ll present things visually, since I think we’ve seen enough integrals for now. First, here’s $1 - \E$ for GGX, which you may recognise from Imageworks’ slides:
Figure 3: $1 - \E$, for GGX.
and here is the decomposition into factors for the various orders of $\Fr$, over the ($\mu$, roughness) domain:
Figure 4: Multiple-scattering Fresnel factors for GGX.
Naturally we have more factors this time, since with multiple scattering there could be $1 \ldots n$ additional reflections before light leaves the microsurface. Given these factors, we can calculate $\Ems$ thusly:
Next, here’s a visualisation of $\Ems$ for our copper material:
Figure 5: $\Ems$ for copper GGX material.
As we can see, it’s just like the multiple-scattering albedo shown in Figure 3, only now it’s been tinted by the different orders of Fresnel reflection. Note how the saturation increases from top left (low roughness, grazing angle) to bottom right (high roughness, incident view angle), as we would expect2.
Finally, here are the spheres again with this LUT-based solution, this time under direct lighting:
Figure 6: Lit spheres, with roughness $\in [\frac{1}{8}, \frac{2}{8}, \ldots 1]$ (left halves: with $\Ems$, right halves: Heitz).
In this example, our revised multiple-scattering approximation (Eq.$~\ref{eq:fms}$) is barely indistinguishable from the Heitz model. The only slight difference, at roughness = 1, comes from the multiple-scattering lobe not being a perfect match to the ground truth, as we already saw in the last last post:
Figure 7: GGX with multiple scattering, roughness = 1
(left half: Imageworks, right half: Heitz).
I will stop things here as this post has already reached a comfortable reading length, but I hope you’ll agree that we’ve made some progress.
In the next post, I’ll cover how the precomputation of $\Ems$ is implemented in code, as well as several approximations with different cost/quality tradeoffs.
1. This is an entirely reasonable choice given its popularly in real-time rendering, and it’s actually what I have been using in all of my examples so far.
2. Of course this is already visualised by the decomposition in Figure 4, but it’s consistent with the behaviour of the Fresnel function and the average number of bounces increasing with roughness. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 3, "equation": 4, "x-ck12": 0, "texerror": 0, "math_score": 0.7017868161201477, "perplexity": 1719.5828755233229}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-34/segments/1534221212910.25/warc/CC-MAIN-20180817202237-20180817222237-00371.warc.gz"} |
https://mne.tools/0.21/auto_tutorials/source-modeling/plot_beamformer_lcmv.html | # Source reconstruction using an LCMV beamformer¶
This tutorial gives an overview of the beamformer method and shows how to use an LCMV beamformer to reconstruct source activity.
# Author: Britta Westner <[email protected]>
#
import matplotlib.pyplot as plt
import mne
from mne.datasets import sample, fetch_fsaverage
from mne.beamformer import make_lcmv, apply_lcmv
## Introduction to beamformers¶
A beamformer is a spatial filter that reconstructs source activity by scanning through a grid of pre-defined source points and estimating activity at each of those source points independently. A set of weights is constructed for each defined source location which defines the contribution of each sensor to this source. Beamformers are often used for their focal reconstructions and their ability to reconstruct deeper sources. They can also suppress external noise sources. The beamforming method applied in this tutorial is the linearly constrained minimum variance (LCMV) beamformer 1 operates on time series. Frequency-resolved data can be reconstructed with the dynamic imaging of coherent sources (DICS) beamforming method 2. As we will see in the following, the spatial filter is computed from two ingredients: the forward model solution and the covariance matrix of the data.
## Data processing¶
We will use the sample data set for this tutorial and reconstruct source activity on the trials with left auditory stimulation.
data_path = sample.data_path()
subjects_dir = data_path + '/subjects'
raw_fname = data_path + '/MEG/sample/sample_audvis_filt-0-40_raw.fif'
# Set up the epoching
event_id = 1 # those are the trials with left-ear auditory stimuli
tmin, tmax = -0.2, 0.5
events = mne.find_events(raw)
# pick relevant channels
raw.pick(['meg', 'eog']) # pick channels of interest
# Create epochs
proj = False # already applied
epochs = mne.Epochs(raw, events, event_id, tmin, tmax,
# for speed purposes, cut to a window of interest
evoked = epochs.average().crop(0.05, 0.15)
# Visualize averaged sensor space data
evoked.plot_joint()
del raw # save memory
Out:
Opening raw data file /home/circleci/mne_data/MNE-sample-data/MEG/sample/sample_audvis_filt-0-40_raw.fif...
Read a total of 4 projection items:
PCA-v1 (1 x 102) idle
PCA-v2 (1 x 102) idle
PCA-v3 (1 x 102) idle
Average EEG reference (1 x 60) idle
Range : 6450 ... 48149 = 42.956 ... 320.665 secs
319 events found
Event IDs: [ 1 2 3 4 5 32]
Removing projector <Projection | Average EEG reference, active : False, n_channels : 60>
72 matching events found
Applying baseline correction (mode: mean)
Created an SSP operator (subspace dimension = 3)
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on MAG : ['MEG 1711']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Rejecting epoch based on EOG : ['EOG 061']
Created an SSP operator (subspace dimension = 3)
3 projection items activated
SSP projectors applied...
Removing projector <Projection | PCA-v1, active : True, n_channels : 102>
Removing projector <Projection | PCA-v2, active : True, n_channels : 102>
Removing projector <Projection | PCA-v3, active : True, n_channels : 102>
## Computing the covariance matrices¶
Spatial filters use the data covariance to estimate the filter weights. The data covariance matrix will be inverted during the spatial filter computation, so it is valuable to plot the covariance matrix and its eigenvalues to gauge whether matrix inversion will be possible. Also, because we want to combine different channel types (magnetometers and gradiometers), we need to account for the different amplitude scales of these channel types. To do this we will supply a noise covariance matrix to the beamformer, which will be used for whitening. The data covariance matrix should be estimated from a time window that includes the brain signal of interest, and incorporate enough samples for a stable estimate. A rule of thumb is to use more samples than there are channels in the data set; see 3 for more detailed advice on covariance estimation for beamformers. Here, we use a time window incorporating the expected auditory response at around 100 ms post stimulus and extend the period to account for a low number of trials (72) and low sampling rate of 150 Hz.
data_cov = mne.compute_covariance(epochs, tmin=0.01, tmax=0.25,
method='empirical')
noise_cov = mne.compute_covariance(epochs, tmin=tmin, tmax=0,
method='empirical')
data_cov.plot(epochs.info)
del epochs
Out:
Computing rank from data with rank=None
Using tolerance 4.1e-09 (2.2e-16 eps * 305 dim * 6.1e+04 max singular value)
Estimated rank (mag + grad): 302
MEG: rank 302 computed from 305 data channels with 3 projectors
Created an SSP operator (subspace dimension = 3)
Setting small MEG eigenvalues to zero (without PCA)
Reducing data rank from 305 -> 302
Estimating covariance using EMPIRICAL
Done.
Number of samples used : 2035
[done]
Computing rank from data with rank=None
Using tolerance 2.8e-09 (2.2e-16 eps * 305 dim * 4.2e+04 max singular value)
Estimated rank (mag + grad): 302
MEG: rank 302 computed from 305 data channels with 3 projectors
Created an SSP operator (subspace dimension = 3)
Setting small MEG eigenvalues to zero (without PCA)
Reducing data rank from 305 -> 302
Estimating covariance using EMPIRICAL
Done.
Number of samples used : 1705
[done]
Computing rank from covariance with rank=None
Using tolerance 4e-14 (2.2e-16 eps * 102 dim * 1.8 max singular value)
Estimated rank (mag): 99
MAG: rank 99 computed from 102 data channels with 0 projectors
Computing rank from covariance with rank=None
Using tolerance 4.3e-13 (2.2e-16 eps * 203 dim * 9.4 max singular value)
GRAD: rank 203 computed from 203 data channels with 0 projectors
When looking at the covariance matrix plots, we can see that our data is slightly rank-deficient as the rank is not equal to the number of channels. Thus, we will have to regularize the covariance matrix before inverting it in the beamformer calculation. This can be achieved by setting the parameter reg=0.05 when calculating the spatial filter with make_lcmv(). This corresponds to loading the diagonal of the covariance matrix with 5% of the sensor power.
## The forward model¶
The forward model is the other important ingredient for the computation of a spatial filter. Here, we will load the forward model from disk; more information on how to create a forward model can be found in this tutorial: Head model and forward computation. Note that beamformers are usually computed in a volume source space, because estimating only cortical surface activation can misrepresent the data.
# Read forward model
fwd_fname = data_path + '/MEG/sample/sample_audvis-meg-vol-7-fwd.fif'
Out:
Reading forward solution from /home/circleci/mne_data/MNE-sample-data/MEG/sample/sample_audvis-meg-vol-7-fwd.fif...
[done]
Desired named matrix (kind = 3523) not available
Read MEG forward solution (3757 sources, 306 channels, free orientations)
Source spaces transformed to the forward solution coordinate frame
## Handling depth bias¶
The forward model solution is inherently biased toward superficial sources. When analyzing single conditions it is best to mitigate the depth bias somehow. There are several ways to do this:
• mne.beamformer.make_lcmv() has a depth parameter that normalizes the forward model prior to computing the spatial filters. See the docstring for details.
• Unit-noise gain beamformers handle depth bias by normalizing the weights of the spatial filter. Choose this by setting weight_norm='unit-noise-gain'.
• When computing the Neural activity index, the depth bias is handled by normalizing both the weights and the estimated noise (see 1). Choose this by setting weight_norm='nai'.
Note that when comparing conditions, the depth bias will cancel out and it is possible to set both parameters to None.
## Compute the spatial filter¶
Now we can compute the spatial filter. We’ll use a unit-noise gain beamformer to deal with depth bias, and will also optimize the orientation of the sources such that output power is maximized. This is achieved by setting pick_ori='max-power'. This gives us one source estimate per source (i.e., voxel), which is known as a scalar beamformer.
filters = make_lcmv(evoked.info, forward, data_cov, reg=0.05,
noise_cov=noise_cov, pick_ori='max-power',
weight_norm='unit-noise-gain', rank=None)
# You can save the filter for later use with:
# filters.save('filters-lcmv.h5')
Out:
Computing rank from covariance with rank=None
Using tolerance 7.1e-13 (2.2e-16 eps * 305 dim * 10 max singular value)
Estimated rank (mag + grad): 302
MEG: rank 302 computed from 305 data channels with 3 projectors
Computing rank from covariance with rank=None
Using tolerance 2.9e-13 (2.2e-16 eps * 305 dim * 4.3 max singular value)
Estimated rank (mag + grad): 302
MEG: rank 302 computed from 305 data channels with 3 projectors
Making LCMV beamformer with rank {'meg': 302}
Computing inverse operator with 305 channels.
305 out of 306 channels remain after picking
Selected 305 channels
Whitening the forward solution.
Created an SSP operator (subspace dimension = 3)
Computing rank from covariance with rank={'meg': 302}
Setting small MEG eigenvalues to zero (without PCA)
Creating the source covariance matrix
Computing beamformer filters for 3757 sources
Filter computation complete
It is also possible to compute a vector beamformer, which gives back three estimates per voxel, corresponding to the three direction components of the source. This can be achieved by setting pick_ori='vector' and will yield a volume vector source estimate. So we will compute another set of filters using the vector beamformer approach:
filters_vec = make_lcmv(evoked.info, forward, data_cov, reg=0.05,
noise_cov=noise_cov, pick_ori='vector',
weight_norm='unit-noise-gain', rank=None)
# save a bit of memory
src = forward['src']
del forward
Out:
Computing rank from covariance with rank=None
Using tolerance 7.1e-13 (2.2e-16 eps * 305 dim * 10 max singular value)
Estimated rank (mag + grad): 302
MEG: rank 302 computed from 305 data channels with 3 projectors
Computing rank from covariance with rank=None
Using tolerance 2.9e-13 (2.2e-16 eps * 305 dim * 4.3 max singular value)
Estimated rank (mag + grad): 302
MEG: rank 302 computed from 305 data channels with 3 projectors
Making LCMV beamformer with rank {'meg': 302}
Computing inverse operator with 305 channels.
305 out of 306 channels remain after picking
Selected 305 channels
Whitening the forward solution.
Created an SSP operator (subspace dimension = 3)
Computing rank from covariance with rank={'meg': 302}
Setting small MEG eigenvalues to zero (without PCA)
Creating the source covariance matrix
Computing beamformer filters for 3757 sources
Filter computation complete
## Apply the spatial filter¶
The spatial filter can be applied to different data types: raw, epochs, evoked data or the data covariance matrix to gain a static image of power. The function to apply the spatial filter to Evoked data is apply_lcmv() which is what we will use here. The other functions are apply_lcmv_raw(), apply_lcmv_epochs(), and apply_lcmv_cov().
stc = apply_lcmv(evoked, filters, max_ori_out='signed')
stc_vec = apply_lcmv(evoked, filters_vec, max_ori_out='signed')
del filters, filters_vec
## Visualize the reconstructed source activity¶
We can visualize the source estimate in different ways, e.g. as a volume rendering, an overlay onto the MRI, or as an overlay onto a glass brain.
The plots for the scalar beamformer show brain activity in the right temporal lobe around 100 ms post stimulus. This is expected given the left-ear auditory stimulation of the experiment.
lims = [0.3, 0.45, 0.6]
kwargs = dict(src=src, subject='sample', subjects_dir=subjects_dir,
initial_time=0.087, verbose=True)
### On MRI slices (orthoview; 2D)¶
stc.plot(mode='stat_map', clim=dict(kind='value', pos_lims=lims), **kwargs)
Out:
Fixing initial time: 0.087 sec
Showing: t = 0.087 s, (50.7, 2.0, -13.3) mm, [18, 12, 9] vox, 5184 vertex
### On MNI glass brain (orthoview; 2D)¶
stc.plot(mode='glass_brain', clim=dict(kind='value', lims=lims), **kwargs)
Out:
Transforming subject RAS (non-zero origin) -> MNI Talairach
1.022485 -0.008449 -0.036217 5.60 mm
0.071071 0.914866 0.406098 -19.82 mm
0.008756 -0.433700 1.028119 -1.55 mm
0.000000 0.000000 0.000000 1.00
Fixing initial time: 0.087 sec
Showing: t = 0.087 s, (57.9, -19.7, -15.6) mm, [18, 12, 9] vox, 5184 vertex
### Volumetric rendering (3D) with vectors¶
These plots can also be shown using a volumetric rendering via plot_3d(). Let’s try visualizing the vector beamformer case. Here we get three source time courses out per voxel (one for each component of the dipole moment: x, y, and z), which appear as small vectors in the visualization (in the 2D plotters, only the magnitude can be shown):
brain = stc_vec.plot_3d(
clim=dict(kind='value', lims=lims), hemi='both',
views=['coronal', 'sagittal', 'axial'], size=(800, 300),
view_layout='horizontal', show_traces=0.3, **kwargs)
## Visualize the activity of the maximum voxel with all three components¶
We can also visualize all three components in the peak voxel. For this, we will first find the peak voxel and then plot the time courses of this voxel.
peak_vox, _ = stc_vec.get_peak(tmin=0.08, tmax=0.1, vert_as_index=True)
ori_labels = ['x', 'y', 'z']
fig, ax = plt.subplots(1)
for ori, label in zip(stc_vec.data[peak_vox, :, :], ori_labels):
ax.plot(stc_vec.times, ori, label='%s component' % label)
ax.legend(loc='lower right')
ax.set(title='Activity per orientation in the peak voxel', xlabel='Time (s)',
ylabel='Amplitude (a. u.)')
mne.viz.utils.plt_show()
del stc_vec
## Morph the output to fsaverage¶
We can also use volumetric morphing to get the data to fsaverage space. This is for example necessary when comparing activity across subjects. Here, we will use the scalar beamformer example. We pass a mne.SourceMorph as the src argument to mne.VolSourceEstimate.plot. To save some computational load when applying the morph, we will crop the stc:
fetch_fsaverage(subjects_dir) # ensure fsaverage src exists
fname_fs_src = subjects_dir + '/fsaverage/bem/fsaverage-vol-5-src.fif'
morph = mne.compute_source_morph(
src, subject_from='sample', src_to=src_fs, subjects_dir=subjects_dir,
niter_sdr=[10, 10, 5], niter_affine=[10, 10, 5], # just for speed
verbose=True)
stc_fs = morph.apply(stc)
del stc
stc_fs.plot(
src=src_fs, mode='stat_map', initial_time=0.085, subjects_dir=subjects_dir,
clim=dict(kind='value', pos_lims=lims), verbose=True)
Out:
0 files missing from /home/circleci/project/mne/datasets/_fsaverage/root.txt in /home/circleci/mne_data/MNE-sample-data/subjects
0 files missing from /home/circleci/project/mne/datasets/_fsaverage/bem.txt in /home/circleci/mne_data/MNE-sample-data/subjects/fsaverage
[done]
Volume source space(s) present...
Computing nonlinear Symmetric Diffeomorphic Registration...
Optimizing translation:
Optimizing level 2 [max iter: 10]
Optimizing level 1 [max iter: 10]
Optimizing level 0 [max iter: 5]
Optimizing rigid-body:
Optimizing level 2 [max iter: 10]
Optimizing level 1 [max iter: 10]
Optimizing level 0 [max iter: 5]
Translation: 22.7 mm
Rotation: 20.7°
R²: 96.5%
Optimizing full affine:
Optimizing level 2 [max iter: 10]
Optimizing level 1 [max iter: 10]
Optimizing level 0 [max iter: 5]
R²: 96.9%
Optimizing SDR:
R²: 99.0%
[done]
Fixing initial time: 0.085 sec
Showing: t = 0.087 s, (55.0, -25.0, -15.0) mm, [27, 18, 12] vox, 16065 vertex
## References¶
1(1,2)
Barry D. Van Veen, Wim van Drongelen, Moshe Yuchtman, and Akifumi Suzuki. Localization of brain electrical activity via linearly constrained minimum variance spatial filtering. IEEE Transactions on Biomedical Engineering, 44(9):867–880, 1997. doi:10.1109/10.623056.
2
Joachim Groß, Jan Kujala, Matti S. Hämäläinen, Lars Timmermann, Alfons Schnitzler, and Riitta Salmelin. Dynamic imaging of coherent sources: studying neural interactions in the human brain. Proceedings of the National Academy of Sciences, 98(2):694–699, 2001. doi:10.1073/pnas.98.2.694.
3
Matthew J. Brookes, Jiri Vrba, Stephen E. Robinson, Claire M. Stevenson, Andrew M. Peters, Gareth R. Barnes, Arjan Hillebrand, and Peter G. Morris. Optimising experimental design for MEG beamformer imaging. NeuroImage, 39(4):1788–1802, 2008. doi:10.1016/j.neuroimage.2007.09.050.
Total running time of the script: ( 1 minutes 40.370 seconds)
Estimated memory usage: 785 MB
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https://stats.stackexchange.com/questions/412606/central-limit-theorem-only-needs-sample-size-n | # Central Limit Theorem only needs sample size, N?
I think explaining the central limit theorem needs two elements: the sample size and the number of samples drawn.
But nobody seems to talk about the number of samples drawn when they are making some infererence $$\mu$$ using the central limit theorem and only mention the sample size, $$N$$ and its distribution, which means they only use one sample group to infer population $$\mu$$.
I thought, however, there should be lots of samples each of at least 30 elements, and accordingly, lots of sample "means", and their distribution, not just the distribution of one sample group.
Please kindly help me to correctly understand the Central Limit Theorem and inferring the population mean, $$\mu$$.
• Can someone explain what's unclear about the question? – Glen_b -Reinstate Monica Jun 12 '19 at 14:38
• @Glen_b I don't understand how "number of sample size" and "number of drawing samples" are different. – Sycorax says Reinstate Monica Jun 12 '19 at 23:05
• You're drawing multiple samples, each of size N (the "sample size"); the other quantity is how many such samples you draw ("number of samples"). I guess it could be clarified a bit with an edit. – Glen_b -Reinstate Monica Jun 12 '19 at 23:55
• @Sycorax: I've cleaned up the phrasing a little, but besides the OP not having English as a first language (and some major, but not uncommon misconceptions) it seemed clear to me – Glen_b -Reinstate Monica Jun 13 '19 at 0:40
• @Roy I've just noticed there's a related question here: stats.stackexchange.com/questions/133931/… – Glen_b -Reinstate Monica Jun 13 '19 at 0:42
1. A single random variable has a distribution; a sample mean from a random sample is a single random variable. Of course you can only observe its distribution by looking at multiple random samples (such as multiple sample means); then as the number of such samples increases the sample (empirical) cdf will approach the population distribution function. The standard error of the sample cdf about the population cdf decreases as the square root of sample size (quadruple the sample size and you halve the standard error).
In short, the number of samples you take (each of size $$n$$) has no impact on how close the distribution of sample means is to being normal ... only on how accurately you can see it when you look at a collection of sample means all from samples of the same size.
To see how close you are to normality at some sample size, you may need a substantial number of sample means. In simulation experiments it is common to look at thousands of such samples so as to get a good sense of the distributional shape.
The picture shows histograms of 20, 300 and 100000 sample means for samples of size n=30 from a skewed distribution. We have some sense of the broad shape in the first one, a somewhat clearer sense of it in the second one, but we get a pretty clear idea of the shape of this distribution of sample means in the third one, where we have a large number of realizations of the sample mean.
In this case sample means don't have close to a normal distribution; n=30 would not be sufficient to treat these means as approximately normally distributed (at least not for typical purposes).
If you want a good sense of how the tails of the distribution behave you may need considerably larger numbers of sample means.
However, when you're dealing with real data, you generally only get a single sample. You have to base your inference (whether you rely on the CLT or not) on that one sample.
2. You may have been misled about what the central limit theorem says.
The actual central limit theorem says nothing whatever about n=30 nor about any other finite sample size.
It is instead a theorem about the behaviour of standardized means (or sums) in the limit as n goes to infinity.
3. While it's true that (under certain conditions) sample means will be approximately normally distributed (in a particular sense of approximate) if the sample size is large enough, what constitutes 'large enough' for some purpose depends on several factors. As we see in the plot above, skewness can (for example) have a substantial impact on the approach to normality (if the population is skewed, the distribution of sample means is also skewed but less so with increasing sample size).
• Thanks for your great reply! I have quick question about it:In short, the number of samples you take (each of size n) has no impact on how close the distribution of sample means is to being normal. Based on your plot, does it mean you drew 20, 300, 1000000 samples(and get the same number of sample means) and each sample of size is 30, and no matter how many samples you drew (or how many times you drew samples), it has no impact on the dist. of sample means being normality? Or I possibly understand your article in a opposite way...? – Roy Jun 12 '19 at 7:01
• Because I just simulated CLT by Python with uniform dist. with 300 samples(each of size is 10), and it looks quite norm, and so I am little bit confused. – Roy Jun 12 '19 at 7:02
• The shape of the distribution you draw from definitely matters; the uniform is a 'nice' case where n even smaller than 10 is pretty close to normal for most purposes (30 is too high a bar unless you're getting well into the tail). If you had done 1000 samples or 1 (each n=10), the distribution of means is the same, as long as you stick to the same population distribution. If you want to emulate my pictures, try a gamma distribution with shape 0.05 (the scale or rate parameter doesn't matter as long as you don't change it); equivalently you could try a chi-square with 0.1 d.f. – Glen_b -Reinstate Monica Jun 12 '19 at 7:16
• Note that your sample means from a uniform are nice and normal-looking but are (demonstrably) not actually normal; they are lighter-tailed than the normal (indeed they have a finite range). This non-normality may not matter much, depending on what you're doing with them. – Glen_b -Reinstate Monica Jun 12 '19 at 7:22
• Wow, yeah, gamma dist. clearly shows what you explained above: the number of sample means has no impact. I wrongly understand CLT, Thanks. And I also found out I thought "point estimation" is based on CLT, and couldn't understand why point estimation use just one sample collection to infer population params. Thanks for your help:) – Roy Jun 12 '19 at 8:06 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 5, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7089851498603821, "perplexity": 513.2599271270162}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875148375.36/warc/CC-MAIN-20200229022458-20200229052458-00037.warc.gz"} |
http://math.stackexchange.com/questions/157851/number-of-terms-in-an-arithmetic-progression/157879 | # Number of terms in an Arithmetic progression
1 and 20 are first and last terms of the arithmetic progression. If all the terms of this arithmetic progression are integers, then find the different number of terms that this arithmetic progression can have ?
-
Sounds like homework. Is it? At any rate, here's a hint. An arithmetic sequence always has the form a, a + n, a + 2n, ... . You know that a = 1 and 20 = a + nk. Go from there. – Rick Decker Jun 13 '12 at 16:19
Let $s$ be the step size and $k$ be the number of terms. Then $1+s(k-1)=20$. Simplify. – Henning Makholm Jun 13 '12 at 16:20
Hi, my doubt is that will you consider : 1 and 20 as a arithmetic progression. – Arpit Bajpai Jun 13 '12 at 16:40
@ArpitBajpai Yes, with step size 19. – process91 Jun 13 '12 at 17:01
Here's an obvious generalization which may be interesting to you, and which exposes the reasoning for the question above: $1$ and $(1+p)$ are the first and last terms of an arithmetic progression, where $p$ is prime. If all the terms of this arithmetic progression are integers, how many different number of terms can this arithmetic progression have?
See if you can generalize Henning's comment regarding your original question which was that the number of terms $k$ with step size $s$ must satisfy $1+s(k-1)=20$ in order to answer this question as well. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.595868706703186, "perplexity": 173.56988366699633}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398457127.55/warc/CC-MAIN-20151124205417-00299-ip-10-71-132-137.ec2.internal.warc.gz"} |
http://mathhelpforum.com/latex-help/164698-show-off-your-latex-skills-print.html | • November 28th 2010, 10:30 PM
Drexel28
Post here any cool LaTeX things you've discovered over the years.
Example:
$\setlength{\unitlength}{.5cm}\begin{picture}(10,10 )\put(2,2){\line(0,2){2}}\put(2,6){\line(0,2){2}}\ put(2,8){\line(2,0){2}}\put(6,8){\line(2,0){2}}\pu t(2,2){\line(2,0){2}}\put(6,2){\line(2,0){2}}\put( 8,2){\line(0,2){2}}\put(8,6){\line(0,2){2}}\put(0, 4){\line(2,0){2}}\put(0,4){\line(0,2){2}}\put(0,6) {\line(2,0){2}}\put(4,8){\line(0,2){2}}\put(4,10){ \line(2,0){2}}\put(6,8){\line(0,2){2}}\put(8,4){\l ine(2,0){2}}\put(10,4){\line(0,2){2}}\put(8,6){\li ne(2,0){2}}\put(4,0){\line(0,2){2}}\put(4,0){\line (2,0){2}}\put(6,0){\line(0,2){2}}\qbezier(0,6)(0,1 0)(4,10)\qbezier(6,10)(10,10)(10,6)\qbezier(10,4)( 10,0)(6,0)\qbezier(4,0)(0,0)(0,4)\qbezier(2,2)(5,5 )(2,8)\qbezier(2,8)(5,5)(8,8)\qbezier(8,8)(5,5)(8, 2)\qbezier(8,2)(5,5)(2,2)\qbezier(3.5,5)(3.5,6.5)( 5,6.5)\qbezier(5,6.5)(6.5,6.5)(6.5,5)\qbezier(6.5, 5)(6.5,3.5)(5,3.5)\qbezier(5,3.5)(3.5,3.5)(3.5,5)\ end{picture}$
• December 16th 2010, 05:41 AM
TheCoffeeMachine
$\boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\ bullet\boxed{\bullet\boxed{\bullet\boxed{\bullet\b oxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\bu llet\boxed{\bullet\boxed{\bullet\boxed{\bullet\box ed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\bull et\boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed {\bullet\boxed{\bullet\boxed{\bullet\boxed{\bullet \boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\ bullet\boxed{\bullet\boxed{\bullet\boxed{\bullet\b oxed{\bullet}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}$
Beat that, Drexel! Don't ask me what it's, though. It's the Penrose staircase inverted for all I know...
Or an optical illusion that gives you the impression that the dots are shrinking when they in fact aren't?
$\boxed{\boxed{\overset{\boxed{\bullet\boxed{\boxed {\boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{ \bullet\boxed{\boxed{\bullet}\boxed{\bullet\boxed{ \bullet}}}}}}}\bullet\boxed{\bullet\boxed{\bullet\ boxed{\bullet\boxed{\boxed{\bullet}\boxed{\bullet\ boxed{\bullet}}}}}}}\bullet\boxed{\bullet\boxed{\b oxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\bu llet\boxed{\boxed{\bullet}\boxed{\bullet\boxed{\bu llet}}}}}}}\bullet\boxed{\boxed{\bullet}\boxed{\bu llet\boxed{\bullet}}}}}}}}{\boxed{\bullet\boxed{\b oxed{\boxed{\bullet\boxed{\bullet\boxed{\bullet\bo xed{\bullet\boxed{\boxed{\bullet}\boxed{\bullet\bo xed{\bullet}}}}}}}\bullet\boxed{\bullet\boxed{\bul let\boxed{\bullet\boxed{\boxed{\bullet}\boxed{\bul let\boxed{\bullet}}}}}}}\bullet\boxed{\bullet\boxe d{\boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed {\bullet\boxed{\boxed{\bullet}\boxed{\bullet\boxed {\bullet}}}}}}}\bullet\boxed{\boxed{\bullet}\boxed {\bullet\boxed{\bullet}}}}}}}}}}$
It's a new game called... not sure what to call it, to be honest.
http://www.overunity.com/index.php?a...ch=42819;image
Ok, you got me! That last one was fake. Worth a try, anyway. (Rofl) I actually tried to make it, but it didn't quite work out.
Could someone try it? Not the colour (as it's not enabled in the forum), but the shape I mean. It would be hard, I suppose.
• December 16th 2010, 06:48 AM
Soroban
. . . . . . . . . . . $\begin{array}{ccccc}
\subset & \sqsupset \\ [-2.7mm]
\supset & \sqsubset \\ [-2.7mm]
\subset & \sqsupset \\ [-2.7mm]
\supset & \sqsubset \\
\end{array}$
"So, how's your stress management course?"
• December 16th 2010, 07:50 AM
Quote:
Originally Posted by TheCoffeeMachine
$\boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\ bullet\boxed{\bullet\boxed{\bullet\boxed{\bullet\b oxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\bu llet\boxed{\bullet\boxed{\bullet\boxed{\bullet\box ed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\bull et\boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed {\bullet\boxed{\bullet\boxed{\bullet\boxed{\bullet \boxed{\bullet\boxed{\bullet\boxed{\bullet\boxed{\ bullet\boxed{\bullet\boxed{\bullet\boxed{\bullet\b oxed{\bullet}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}$
.
Looks like a view of a skewed Mayan pyramid with a cannonball on each step
while holding the reigns of a parachute.
• December 16th 2010, 03:16 PM
Krizalid
1 Attachment(s)
want me yo show my latex skills? ah well, i attach here a PDF that i'm currently doing.
it's in spanish.
i got another ones, like geometry pictures, etc.
• December 17th 2010, 10:28 AM
Soroban
. . . . . . . . . . $\boxed{ \begin{array}{c}\quad | \quad \\ [-1mm] \quad | \quad \\ [-2mm] \quad \bowtie \quad \\ [-2mm] \quad | \quad \\ [-1mm] \quad | \quad \end{array}}$
"Move to the rear of the elevator, please." | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 6, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7647834420204163, "perplexity": 2752.8311022735306}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1394011250349/warc/CC-MAIN-20140305092050-00075-ip-10-183-142-35.ec2.internal.warc.gz"} |
http://www.archive.org/stream/schoolminesquar27chemgoog/schoolminesquar27chemgoog_djvu.txt | # Full text of "The School of Mines Quarterly"
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p., >^- '■'
►
HARVARD UNIVERSITY
LIBRARY OF THE
Department of Mining
and Metallurgy
\L
THE
SCHOOL OF MINES
QUARTERLY,
JOURNAL OF APPLIED SCIENCE.
Vol. XV.
November, 1893, to July, 1894.
COLUMBIA COLLEGE,
NEW YORK CITY.
l894r
TV a 7
MAY 19 1908
cr ^
BOARD OF EDITORS.
A. J. MOSES, Adj. Prof, of Mineralogy. E. WALLER, Analytical Chemist.
J. F. KEMP, Prof, of Geology. J.L.QREENLEAP, Adj. Prof. Civil Engineer'
R. PEELE, Jr., Adj. Prof, of Mining. JOS. STRUTHERS, Tutor in Metallurgy.
Managing Editor, A. J. MOSES.
SCHOOL OF MINES
QUARTERLY,
VOL. XV.
November, 1893, to July, 1894.
AUTHORS' INDEX.
PACE
Berry, Wilton G. Sec Martin and Berry.
Bellom, Maurice, Present Condiiion of the Mechanical Preparation of Ores
in Saxony, Hartz and Rhenish Prussia (continued from Vol. XIV.) i6, 114
Black, Alexander L., An Ore Bucket for Inclined Shafts 47
An Assay Furnace for Burning Wood. , 50
Chester, Albert H., Acanthite f om Colorado 103
CusHMAN, A. R. See Wells & Cushman.
Foster, Wolcott C, Details of Modern Water- Works Construction :
Part I. Cast- Iron, Bell and Spigot Pipe, Special Castings^ Flexible Joints.. 89
Part II Cast- Iron Flanged' Pipe and Special Castings ; Valves 230
Hamlin, A. D. F., Catallel, Metallel, Synallel. 222
Hutton, F. R., a Relation of Engineering to Progress and Civilization 1 10
Iles, Malvern W., Curdling of Milk 105
KrwABARA, M., The Kosaka Mining and Reduction Works, Rice hoo, Japan., 355
Langmuir, a. C, Index to Literature of Didymium 33
LuQUER, Lea McI., The Optical Recognition and Economic Importance of the
Common Minerals Found in Building Stones 285
Index to Mineralogical Literature 163
Martin, Edward W„ and Berry, Wilton G., Method for Determining
Nitrates in Potable Waters by the Use of Sodium Amalgam ii
Moses. Alfred J., Simplified Method for Obtaining the Axial Cross of any
Crystal from any Projection of the Isometric Axes. 214
Index to Mineralogical Literature 163
Newbrough , W., Engineering Notes on Irrigation Canals 1 89
Peele, Robert, Jr., /^ Primitive Smelting- Furnace 8
A Peruvian Salt Mine 219
RlES, Heinrich, On the Occurrence of Cretaceous Clays at Northport, Z. /.... 354
Self, Edward D., Project for Utilizing Bassasseachic Falls 345
Struthers, Joseph, A French Regenerative Gas- Furnace 138
Abstracts^ Metallurgy 66
PAGB
Terhune, Richard H., A Plant for Granulating Slag io8
Waller, Elwyn, Abstracts^ Analytical Chemistry 52, 150, 275, 375
Wells, J. S. C, and Cushman, A. R., Schemes for Qualitative Ana lysis.. ..2^4* 3^5
SUBJECT INDEX.
All Abstracts are printed in Italics; and those relating to metallurgy or to chemical
analysis appear only under the headings Metallurgy and Analytical Chemistry.
Abstracts, Analytical Chemistry 52, 150, 275,375
Metallurgy 66
Air-Blast ClassiBcalion 118
Albite in Building Stones 326
Amphibole in Building Stones 315
Analytical Chemistry Abstracts:
Agitator for the Precipitation of Phospho-Molybdate 52
Alkalimetric Solutions^ Standardizing^ 52
Alkalinity of Liquids Containing Chlorine 150
Alumina in Slags 65
Aluminum Apparatus 52
in Bone Black 54
Ammonia in Zinc Dust, 52
by Nessler Reagent ;.. 375
Ammonium- Magnesium Phosphate. 155
Arsenic in Copper 378
in Iron and Steel. 64
and Antimony Titration 57
Arsenious Acid Volumetric Solutions 377
Barium in Rock Analysis , 275
Volumetric 376
Barium-Sulphate 60
in Presence of Silica 281
Precipitate 154
Baryta^ Strontia and Lime Separation 53
Bismuth Separation from Copper 378
Boric Aciii. 60
in Wines 280
titration 52
Methods for. 379
Boronatrocalcite analysis 65
Bromine Vapor in Separation of Metals 151
from Copper 152
Cesium Separation 150
Carbon in Iron, Methods for 380
in Iron and Steel. 60, 62
in Steel. 60, 155, 156
Carbonic Acid with Soluble Sulphides 380
Carborundum Analysis 156
PAG8
Cerium Reaction^ 57
from La and Di 279
Chlorates, Estimating 156
Chlorin€y Estimating Free 153
Titration 154
Chromium Determination 54» '5^
in Iron and Steel, 64
Citrate Soluble Phosphoric Acid, 379
Cobalt and Nickel Separation 277
Coppery Foreign Metals in Commercial. 277
Impurities in 277, 377
in Iron and Steel, 63
Titration 55
Cyanic Acid 58
Electrolytic Methods 57
Separations 57, 153
Ag and Au 377
FilUr Paper 375
Filtration 150
Free Acids in Salts of Heavy Metals 375
Galena Analysis 152
GlasSf Action of Acids on , 375
Graphite in Iron and Steel 63
in Pig- Iron 281
Hydrochloric Acid Determination 5
Indicators in Sulphide Titrations 150
International Standards for Analysis of Iron and Steel. 157
Iodine in Presence Br and CI .• 279
Iron Analysis 62
Dichromate Titration 151
in Bone Black 54
in Copper Sulphate 151
in Ores 376
Microchemica I Detection 150
Reducing for Titration 151
and Steel International Standards of Analysis 157
Oxide in Iron and Steel, 63
Volumetric 152,278
and Copper Separations 152
Electrolytic 153, 278
and Tin Separation 56
Lime in Slags 65
Magnesia in Slags 65
Manganese Determination 55
in Iron and Steel. 55, 64
in Manganese Bronze 150
Permanganates 55
Reznew of Methods 275
VI
• PACK
Mercury Colorimetric 56
Metals as Oxides Determining. 275
Microchemical Analysis Rocks 66
Mineral Separation 66
New Element 380
Nickel^ Commercial^ Analysis of. 376
Determination ; 151
Estimation 55
in Nickel SteeL 276
Nickel and Cobalt, See Cobalt and Nickel.
Nitrates 61
Estimating 156
in Potable Waters 281
Nitrites^ Estimating. 156
Nitrogen in Nitrates 61
Organic Matter 61
Oxalic Acid. 281
Oxygen Available in Manganese Minerals 61
Pandermite Analysis, 65
Phosphomolybdate, Agitator for Precipitation 52
Phosphoric Acid^ Alkalimetric 379
Determining 59, 155
Volumetric {54»379
in Basic Slags 58
Phosphorus in Coal and Coke. 280
Colorimetric 59
in Iron 58, 62, 379
in Steel, -. 62, 280,378
Phosphor Tin 377
Platinum Alloys « 377
Potassium Determination 53
lodate. Preparation of. 157
Portland Cement. 65
Pyrophosphoric Acid, Volumetric 52
Pare Earths^ Approximate Determination of Equivalents 279
Silica Estimation 380
in Slags 65
Silicates, Analysis 156
Silicon in Irons 60
in Iron and Steel. 62
Silver, Volumetric 278
Slag Analyses « 65
Sodium Peroxide as Reagent 52
Specific Gravity Liquid. 66
Standards^ International^ for Analysis of Iron and Steel. 157
Steel Analysis 62
Strontium in Rock Analysis 275
Sulphocyanic Acid Determination 58
Vll
PAGB
Sulph-ur Evolution Method.,,.,, 66
i» Sulphides 59
in. Iran and Steel, 63
in Manufactured Iron 154
in Pyrites 154, 378
in Slags 65
Tartar Knutic Standard Solutions 151
Thorium Separation 279
Tin-Ores^ Analysis 56
Titanium from Iron 376
in Iron and Steel, 63
Tungsten in Iron and Steel. 63
Ulexite Analysis „ 65
Uranium^ Colorimetric 15 1
from Chromium „ -279
Volatilization of Salts During Evaporation „ 375
IVater Analysis „ 157
Zinc- Ores, Examination of, „ 275
Anoithite in Building Stones.^.. ..^ „ 326
Apatite in Building Stones 302
Assay Furnace Burning Wood 50
Augite in Building Stones 312
Augustine Process at Osaka, Japan a 364
Axial Cross, Simplified Method of Constructing 214
Bassasseachic Falls, Utilization of. 345
Bell and Spigot Pipe 89
Bibliography Building Stones „ 334
Biotite in Building Stones 318
Bolivian Smelting Furnace 8
Book Reviews:
Lc Cuivre. By Paul Weiss 384
Field-Book for Civil Engineers. By Daniel Carhart 162
Gas-Lighting and Gas-Fitting. By William P. Gerhard 384
Helical Gears. By a Foreman Patternmaker 159
Lecture Notes on Theoretical Chemistry. By Ferdinand G. Wiechmann 76
Manual of Practical Assaying. By H. Van F. Furman 161.
'Mechanics of Hoisting Machinery. By Weisbach and Herrman 158
Mineral Industry Vol. IL, 1894. Edited by Richard P. Rothwell 381
Miners' Pocket-books, a Review of ; The Coal and Metal Miners' Pocket-
book, compiled by Colliery Engineer Co. ; Text-Book of Mining For-
mula*, by Robert W. Dron ; Notes and Formulae for Mining Students,
by J. H. Merivale ; Miners* Pocket-book, by C. G. W. Lock ; Pocket-
• book, for Miners and Metallurgists, by F. D. Power; The Miner's
Handbook, by John Milne 76
Ore-Deposits of United States. By Jas. F, Kemp 282
Plane Trigonometry. By S L. Loney 282
Resistance of Ships and Screw Propulsion. By D. W. Taylor 158
Vlll —
PAGE
Text-Book on Coal-Mining for the Use of Colliery Managers and Others.
By Herbert W. Hughes 75
Thermodynamics of Reversible Cycles in Gases and Saturated Vapors.
By M. I. Pupin .*. 282
Vol. VII., pt. I. Report (on clays) of the Geological Survey of Ohio. 161
Building Stones, Recognition and Importance of Minerals In 285
Building Stones Bibliography 334
Bulletin of Alumni and College News:
Department of Mining 83
Physics. 83
Mechanics 84
Metallurgy 85
Mineralogy 85
Geology 87
Biology 87
Mechanical Engineering 88
Electrical Engineering 88
Architecture 185
Changes in the School of Mines 180
Trowbridge Fellowship 181
University Press , 182
Pulitzer Fund 183
Instructors and Students 184
Library 184
Travelling Class in Architecture 186
Calcite in Building Stones.... 299
Cast-Iron Flanged Pipe v 230
Catallel 222
Chemical Analysis, Standard Methods 143
Chemical Reactions 244
Chlorite in Building Stones.. 306
Choices of Treatment in Ore-Dressing 13S
Chromite in Building Stones 291
Chrysolite in Building Stones 310
Citric Acid Effect on Minerals 334
Classification by Air-Blast 118
Clay in Building Stones 333
Copper and Silver Smelting at Osaka, japan 355
Cost of Ore-Dressing 134
Cretaceous Clays at Northport, L. 1 354
Cross-Section Calculations, Irrigation Canals 195
Crystal Axes, Projection of 214
Curdling of Milk 105
Cutting-in, In Iron Pipe 101
Cyanite in Building Stones 331
Diabase 330
Dichroite in Building Stones 311
Didymium, Index to Literature ^3
IX
9AGB
Diorite 318, 330
Distributor, the Meintcke 21
Dolomite in Building Stones 300
Eddy Valve 235
Elaeolite in Building Stones 303
Elbows in Iron Pipe , 95
Engineering Notes on Irrigating Canals 189
Engineering Relation to Progress and Civilization no
Enrichment of Ores 126
Enstatiie in Building Stones 308
Epidote in Building Stones 321
Errata, Wells-Cushman Schemes 385
Feldspar Porphyry 330
Feldspars in Building Stones 324
Plre-Damp, Detection and Measurement 145
Flanged Pipe 230
Garnet in Building Stones 291
Gas Furnace, French Regenerative ^ 138
Gneiss 318, 321, 330
Granite 315. 318, 320, 328
Graphite in Building Stones 295
Hematite in Building Stones 295
Hexagonal Axial Cross 216
Hornblende in Building Stones 315
Hypersthene in Building Stones 308
Ilmenite in Building Stones 295
Index to Literature of Didymium 33
Index to Mineralogical Literature 163
lolite in Building Stones 311
Irrigation Canals, Notes on 189
Isometric Axial *Cross 215
Kaolin in Building Stones 333
Kosaka Mining and Reduction Works 355
Limestone 290, 299, 301
Limonite in Building Stones 291
Location Survey Irrigation Canals 199
Losses in Concentration of Ores 126
Magnetic Separation of Ores 124
Magnetite in Building Stones 290
Mapping Irrigation Canals 204
Marbles 301
Marcasite in Building Stones 289
Mechanical Preparation of Ores in Saxony, Hartz and Rhenish Prussia 16, 114
PAGB
Meinicke Distributer 21
Spitzlutten 17
Menaccanite in Building Stones 29$Metallel.^ «. 222 Metallurgy Abstracts: Aluminum 73 Antimony^ Electric Exttactionof 74 Basic Steel. 69 Bessemer Process in Sweden 69 Bituminous Coal as Fuel. ^ 66 Blast-Furnace, Improved Form of. 68 Blowing- Engines 67 Coke as Fuel. 66 Coking Ovens,'. 67 Copper Treatment at Lake Superior 70 Electro- Metallurgy 74 Foundry Practice 69 Fuels 66 Gold Stamp-Mills 73 Illuminating Gas as Fuel. 67 Iron Alloys 7° and Steel. 70 Cupolas 69 Lead and Copper 70 Microstructure of Steel. 7° Mtllwork 69 Oak Wood as Fuel. 67 Open-Hearth Steel Process 69 Pearce Turret Roasting- Furnace 7* Petroleum as Fuel 66, 67 Pig-Iron^ Machine for Breaking 69 Pyrometers 68 Russet Process ^0 Separation of Blende from Pyrites 68 Siemens- Martin Furnace 69 Silver in Zinc Ores 72 Lixiviation 7^, 7' Slag Calculation 68 Specific Heat of Metal. 74 Steel. 69 Sulphuric Acid Process Silver 71 Tuyeres 68 Valve-Gear for Blowing- Engine 67 Zinc Ores for Silver 72 Mica Group in Building Stones 318 Mica Schist 321 Microcline in Building Stones 325 Milk Curdling 105 Mineralogical Literature Index 163 XI — PACE Minetals, Apparatus for Separation of Minerals of High Specific Gravity 147 of Building Stones, Recognition and Importance 285 Production of World in 1892 381 Miners' Pocket Books 76 Mining and Reduction Works at Osaka, Japan 355 Monoclinic Axial Cross 217 Muscovite in Building Stones 318 Nephelite in Building Stones 303 Nitrates by Sodium Amalgam ii Norite 330 Oligoclase in Building Stones 326 Olivine in Building Stones 310 Optical Importance and Recognition of Minerals in Building Stones 285 Ore Bucket for Inclined Shafts 47 Ore-Dressing in Saxony, Hartz and Rhenish Prussia 16, 114 Ores Purchasing, Silver, Gold and Lead i Orthoclase in Building Stones 324 Orthorhombic Axial Cross 217 Peruvian Salt Mine 219 Phlogopile in Building Stones 318 Plagioclase in Building Stones 326 Projection of Crystal Axes 214 Purchasing Ores 5 Pyrilc in Building Stones 288 Pyroxene in Building Stones 312 Pyrrhotite in Building Stones 289 Quantitative Analysis Schemes 244 Quartz in Building Stones 296 Regenerative Gas Furnace, French 138 Regulations for Irrigation Canals 212 Rutile in Building Stones 292 Salt Mine, Peruvian 219 Sandstone 289, 298, 301. 321, 330 Sanidine in Building Stones 325 Schemes for Qualitative Analysis 244 Separators, Magnetic ,.... 124 Air-blast 118 Serpentine in Building Stones 332 Silver Ores, Purchasing i Slag Granulating, A Plant for 108 Smelting, Cost of. 2 Smelting Furnace, Primitive '. 8 Sodium Amalgam for Nitrates ii ** Specials " in Iron Pipe 98 Specific Gravity Apparatus for Minerals I47 Sphene in Building Stones 322 Spigot-pipe 230 Spitzlutlen, the Meinicke 17 Standard Methods Chemical Analysis 143 XII PAGE Staurolite in Building Stones 307 Stein Table 23 Surveyor Irrigation Canal 189 Syenite 318, 330 Synallel 222 Table, the Stein 23 the Linkenbach 27, 114 Tetragonal Axial Cross 216 Titanite in Building Stones 322 Tourmaline in Building Stones 304 Trap and Basalt 3^5 Triclinic Axial Cross „ 218 Valves „._ ^. 232 Viridite in Building Stones 307 Water, Nitrates by Sodium Amalgam ^ 11 Water-power of Bassasseachic Falls ^ 345 Water-works Construction ^ 89, 230 Weirs on Irrigation Canals 192 World's Production of Minerals in 1892 33i Works for Ore-Dressing, Plan for 137 Ziervogel Process at Osaka, Japan « 358 Zircon in Building Stones , 294 Vol. XV. No. t. NOVEMBER, 1893. THE SCHOOL OF MINES QUARTERLY. A JOV^XrPiAI. OF APPLrlBD SCIBI^CB. •4«»> BOABB OF EDITORS. A. J. MOSSS, Adj. Prof, of Mineralogy. E. WALLER, Prof. Analytical Chemistry. J. F. K£MP, Prof, of Geology. J. L. GREENLBAP, Adj. Prof. Civil Engineer'^. R. PE&LrK, Jr., Adj. Prof. Mining. JOS. STRUTHERS, Tutor in Metallurgy. Managing Editor, A. J. MOSES. Business Manager, JOS. STRUTHERS. CONTENTS: Purchasing Silver-, Gold-, and Lead-Ores. By H.Van F. Furman, E.M., x A Primitive Smelting- Furnace* By Robert Pcele, Jr 8 Method for Determining Nitrates in Potable Waters by the Use of Sodiam Amalgam. By Edward W. Martin and Wilton G. Berry ii Present Condition of the Mechanical Preparation of Ores in Saxony, Hartz and Rhenish Prussia. By M. Maurice Bellom i6 Index to the Literature of Didymium — 1842- 1893. By A. C. Langmuir, 33 An Ore-Bucket for Inclined Shafts. By Alexander L. Black 47 An Assay Kurnace Burning Wood. By Alexander L. Black 50 Abstracts , 5* Book Rcvie-ws 75 Bulletin of Alumni and College News 83 COLUMBIA COLLEGE. NEW YORK CITY. at the New York Post Office as Second Class Matter. TWO OOI-I'A^® PER YEAR. FIFTY CENTS PER NUMBER. s • w^c^m •iio**^** be made payable to Order of •« The School of Mines Quarterly.'' All *♦— «c MANUFACTURERS OF Jenkins' Bros. Valves and Jenkins' Standard Packing. NEW TORE, BOSTON, CHIOAGO, PHILADELPHIA Mmmvw UiLii..Ain ^t . f ...v. w -1 "WOBKS, FATEBSON, NBW JEB8BT. Office, 100 and 102 Reade Street, New York. MANUFACTURERS OP FILES AND RASPS OF SUPERIOR QUALITY. We make ftUALITY and FINE WORK- MANSHIP our first consideration. Capacity of plant 1250 DOZEN a day. Illas trated Catalo g u e mailed on receipt of 6 centi pottage. Leading houses throughout the United States dealing in Hardware or Machinists' Supplies carry our Piles in stock. . .r^ THE Vol- SCHOOL OF MINES QUARTERLY. XV. NOVEMBER, 1893. No. i PURCHASING SILVER-, GOLD- AND LEAD-ORES. By H. van F. FURMAN, E.M. At our western metallurgical centres, as Denver, Pueblo and Salt Lake City, the margin in the ores has become so slight, owing to the fierce competition between rival smelters, the prevailing scarcity of desirable fluxing-ores, and the declining price of silver, that ores are no longer purchased upon the assay value in silver, gold and lead, and a rough guess as to the probable cost of smelt- ing, but the price paid for a lot of ore is based upon the assay value of the ore and upon its chief constituents, as determined by chemical analysis and calculation as to the actual cost of treat- ment. In determining the price to be paid for an ore, the following points must be taken into consideration : First. — The assay value of the ore in silver, gold and lead ; cop- also being determined provided much is present. Second. — The chemical composition of the ore. SiOg and Fe almost invariably determined. Mn, Zn and CaO are frequently determined, and S, As, Sb, BaO, MgO and AI2O3 are occasionally determined. J^hird. — The silver, gold and lead losses in roasting and smelt- Faurth, — The cost of roasting. VOL. XV.— I 2 THE QUARTERLY. Fifth, — The cost of smelting", including the cost of fluxes and the cost of coke and charcoal. Sixth, — The character of the ore (coarse or fine). Seventh, — Desirability of the lot at the time of purchase. Eighth, — Market value of the bullion at the time of purchase. The assay value in silver, gold and lead is always determined on each lot of ore unless any of these elements are known to be ab- sent. Fire assay is the method adopted. Copper, if present in sufficient quantity, is determined by volumetric cyanide assay or by gravimetric battery assay. The analysis of the ore for its chief constituents, as silica and iron, is quite as important as the assay for silver, etc., as the cost of treatment depends largely upon the mineralogical composition of the ore. The losses in silver, gold and lead in treatment must be known in order to make the proper deductions from the gross value. These losses will depend largely upon the general character and composition of the bulk of the ores treated and the individual practice at any particular works. The Colorado practice (Denver, Pueblo and Leadville) is to pay for 95 per cent, of the silver con- tents, settlement being made on the basis of New York quotation for silver on the day of purchase, ^19 per ounce for the gold, and so much per unit for the lead which the ore contains. The price per unit for the lead is based upon the market price of lead in New York upon the day of purchase and the cost of handling the bullion, including the freight to New York and refining charges. The cost of roasting will depend upon the price of labor and fuel, the character of the fuel, and the type of roasting furnace adopted. For example, with the new automatic roasting furnace which Dr. Richard Pearce has lately patented and put in operation at the Boston and Colorado Works at Argo, Colorado, the cost of roasting at Argo is considerably less than$\ per ton. With prices
for labor and fuel such as prevail in Denver, the cost of roasting
in a long-hearth reverberatory furnace (the usual practice), with a
capacity of from 10 to 12 tons of ore per furnace per day, is about
$2 per ton. As the ore is never roasted ** dead,'* the roasted charge usually carrying 5 to 6 per cent, of sulphur, allowance will have to be made for the treatment of the matte (handling and roasting), which will be produced from the roasted ore when it is smelted. PURCHASING SILVER', GOLD- AND LEAD-ORES. 3 and the interest on the silver, gold and lead value which the matte has. Under the same conditions as above, 1^0.25 to$0.30 will gen-
erally cover this item, so that the cost of roasting in reverberatory
furnaces will be about ^2.25 per ton. As too much 6ne ore cannot
be treated in the blast-furnaces, some of the roasted ore will have to
be fused or slagged. This involves an additional expense of from
$0.25 to ;Jo.7S per ton, so that the total average cost of roasting, at Denver, in reverberatory furnaces, may be stated to be about ;f 2.50 to$2.75 per ton.
The cost of smelting will differ in each locality and according
to the general practice of each individual works, and will, more-
over, depend upon the composition of the ore (cost of fluxing), the
cost of fluxes, the character of the ore (raw smelting, roasting,
coarse or fine), the cost of fuel, the cost of labor, etc. Being made
up of so many variables, this question will necessarily have to be
determined in each individual case by the actual results obtained
in working and after quite extensive operations. With prices as
follows: Common labor (lO-hour shifts), Jji./S ; feeders, ore
wheelers, etc. (12-hour shifts), |!2.5oper day; furnacemen (12-hour
shifts), II3 per day ; engineers and foremen, ^3.50 to $4 per day ; coke ( 10 per cent, ash),$7 per ton ; limestone (50 per cent, excess
CaO), S1.25 per ton ; iron-ore (70 per cent, excess FeO), $^ per ton; and steam fuel (mine slack),$\*^o per ton; and with a large-sized
modem plant (capacity about 400 tons per day), the cost of smelt-
ing a neutral ore (composition SiOj = 30 per cent., Fe = 30 per
cent., Pb = 13 per cent., Zn = 8 per cent., and S = 5 per cent.),
will be about ^$4.50 per ton. This cost is distributed somewhat as follows : Labor, ^i 90 General expenses (office exp. management), etc, . . . o 27 Fuel for power, o 10 Interest, depreciation and repairs, o 50 Coke (15 per cent, charge), ^ , i 36 Limestone (0.3 ton), ^ . , o 37 This figure of %^.^o per ton is the basis of the ore calculations at some of our large Denver and Pueblo works. Of course, this cost is liable to fluctuation from time to time. Having arrived at the cost of smelting a neutral ore it becomes necessary to deter- .V 4 77^^ QUARTERLY. mine what charges or allowances to make for each unit of silica, iron, zinc, etc., in excess of the neutral point. Taking the above figures as a basis we find that each unit of SiOj in excess of iron should be charged for at fifteen cents, and that each unit of iron in excess of silica should be given credit to the amount of fifteen cents. Each unit of lime should be given credit to the amount of six cents. The same credit is given for manganese as for iron, and the same credit is given for magnesia and baryta as for lime, provided the ores do not carry a high percentage of MgO or BaO. Over 4 to 5 per cent, of MgO and BaO in the slags is undesirable (see **The Calculation of Lead Blast-furnace Charges," School of Mines Quarterly, Vol. XIV., No. 2, p. 136). It is customary with the Denver smelters to charge fifty cents per unit for all zinc in excess of the 8 per cent, limit. A charge of fifty cents per unit for arsenic should be made. The character or condition of the ore should always be taken into consideration. Fine ore is undesirable, as it causes the fur- naces to run slow, thus increasing the cost of smelting, and if present on the furnace charge to too great an extent it is liable to cause trouble with the furnaces. When an ore requires previous roasting fineness is an advantage, as if in lump form it will require crushing. The desirability of the lot at the time of purchase will frequently be a considerable figure in the price which will be paid for the lot, especially when the lot is sold on the public market to the highest bidder. This will depend upon the local conditions prevailing at the time of purchase. The market value of the bullion produced is of great importance in arriving at the value of an ore and its cost of treatment. Upon the market value of the bullion will depend, to a large extent, the price per unit which will be paid for the lead. The market value of the bullion, as far as lead is concerned, will be the value of the lead according to New York quotation upon the day of sale less freight to New York and refining charges. If the net value of lead at the works is ^60 per ton, and the loss in smelting is 8 per cent, the net value of each unit of lead will be 1^0.552. There is generally a profit to the smelter on all gold purchased at$19 per ounce as the smelter receives J>20per ounce for the gold
in the bullion from the refiners and usually makes no gold loss in
smelting. Of course there is some loss of gold in smelting, but
this loss is usually more than made up by the small amounts of
gold in certain ores where the amount of gold is so small that it is
not paid for.
In purchasing ore by bid in the public market, that is, from the
public sampling works, the custom is to bid so much net for the
ore at the sampling works. In purchasing ore by contract with
the mines or ore brokers the price paid is usually based upon a
sliding scale. For example : Oxidized lead ore, gangue silica,
oxide of iron, carbonate of lime, baryta, and occasionally zinc.
Treatment charges based upon $4.50 per ton neutral basis (SiOj = Fe) and additional charge of fifteen cents per unit for all SiOj in excess of Fe and corresponding allowance of fifteen cents for all Fe in excess of SiOj. An allowance of six cents per unit for all CaO and BaO. No charge for Zn below 8 per cent. If zinc runs above 8 per cent a charge of fifty cents per unit for all Zn in excess of the 8 per cent, limit to be made. Lead to be paid for as follows, based upon New York quotation of JI4 per 100 pounds : Under 5 per cent., 5 per cent, and under 10 per cent., 10 per cent, and under 20 per cent., 20 per cent, and under 30 per cent., 30 per cent, and under 40 per cent., 40 per cent, and under 50 per cent., 50 per cent, and over, » . nothing. 25 cents per unit. 35 cents per unit. 40 cents per unit. 45 cents per unit. 50 cents per unit. 55 cents per unit. For every five cents per 100 pounds fluctuation of lead in New York an allowance of one cent per unit to be made, up or down. Gold to be paid for at the rate of ;^I9 per ounce, and 95 per cent. of the silver to be paid for at New York quotation on the day of purchase. The method of calculation is best illustrated by the following examples^, using the above figures as a basis, and assuming$4
per 100 pounds for lead and $0.83 per ounce for silver as the New York quotations: Example No, 7. — Sulphide Ore — Conce?iirates, Composition, — SiO,, lo per cent. fe, 37 " Zn, 7 ** Au, 1.2 ozs. per ton, Ag, 10.5 '• " THE QUARTERLY. Treatment. — Roast ing, . Smelting, . Less for Fe excess. Net cost of treatment, Value, — Ag (95 per cent, of 10.5 ounces, at$0.83),
Au (1.2 ounces at j(20.oo),
Total gross value.
Less for treatment, .
Total net value,
Per ton.
$2.50$7«>
4.05
$2.95$8.28
24.00
$32.28 2.95$29.33
In bidding upon the above ore in the public market the smelter
would deduct from the net value of SI29.33 per ton a certain sum
for profit, as, for example, ^3.50, the net bid then being ^{25. 83
per ton.
If the ore was being purchased by contract, the treatment
charge upon a neutral basis being jJq.oo per ton, and gold being
paid for at the rate of Jl 19.00 per ounce, the figures would be as
follows :
Treatment,
Less for Fe excess,
$9.00 4.05 Credit$1.00 per ounce for Au (1.2 ounces), . . . .
For treatment and profit,
Example No, 2. — Ore Oxidised — Coarse.
1.20
$6.15 Composition, — Si O ,, Fe. CaO, Zn, Ag. Au, • • Treatment. — Smelling, Excess of SiOji, at 15c. (20 per cent.), Less for CaO, at 6c. (6 per cent.) . Net cost of treatment, . 32 per cent. 12 •' 6 •* 2 •* 25 50 ozs. per ton. 0.1 ** ** Per ton.$4.50
3.00
$7.50 .36$7.H
Value. — Ag (95 per cent, of 50 ounces), at 83c.
Au (o.i ounce, at $20 00), Pb (25 per cent., at$0,552), .
Total gross value,
Less for treat ment.
Total net value, .
^39.43
2.00
13.80
^55.23
7.14
$48.09 Upon the basis of the above contract schedule the figures would be as follows : Value. — Ag, .... Au (o.i ounce, at$19 00),
Pb (25 per cent., at 40c.),
Less treatment.
Price paid per ton,
^39 43
1.90
10.00
$51.33 7.14$4419
Profit to the smelter = ;J48.09 — ;?44.i9 = $1-^0 per ton. i Example No, 3. — Ore Sulphide — Lump, CompMition,— SiOj, Fe, Zn, Ag. Au, Treatment. — Crushing, ..... Roasting, ..... Smelting, Excess of SiOj (5 per cent.\ at 15c. Excess of Zn (10 per cent.), at 50c. Net cost of treatment, . Value. — Ag (95 per cent, of 25 ounces), at 83c., . Au (0.3 ounces, at$20.00), . . .
Pb (10 per cent., at $0,552), Gross value, . Less for treatment, Total net value. 25 per cent. 20 " 18 " « 10 25 ozs. per ton. 0.3 " •' Per ton.$0.50
2.50
4.50
075
5.00
$13.25$1971
6.00
1.23
13.25
$17-98 For such an ore the shipper would receive about ^14.00 per ton. 8 THE QUARTERLY. A PRIMITIVE SMELTING-FURNACE. By ROBERT PEELE, Jr. In one or two places on the high table-land of Central Bolivia, the Indians use a singular little furnace for smelting silver-ore. Though it has an extremely small capacity, and is wholly unsuited to modern requirements, still, as a survival of the times of the Incas, it possesses some interest as a metallurgical curio. The furnace is called, in the native Quichua language, " Huaira- china," meaning literally ** a place where the wind is utilized." The accompanying cut, from a photograph by the writer, gives a good idea of the form and size of this furnace. It is built of fire- clay, is usually only from 30 to 34 inches high, and has an irregu- lar oval cross-section, the inside dimensions being 4 or 5 inches by 8 inches. The inside height, from the bottom of the hearth to the edge of the open top, is generally not more than 26 inches. Near the bottom of the furnace, as shown in the illustration, there are two main fire openings with wide lips, placed opposite each other on the longer sides of the oval, each 6 inches wide by 3 inches high. On one of the shorter sides, and a little below the level of the large holes, there is a smaller opening. 2^ inches diameter, which serves as a tap. Ranged above the fire doors are three rows of 2 by 2^ inch air-holes on each side of the furnace, and below each of these is moulded a small lip of clay. The first row from the bottom comprises four holes, two on each side; in the rows above there are three holes on a side, all being placed symmetrically and exactly opposite one another. The walls are only 2 inches thick, and the top entirely open. It is usual to set the furnace on a rock or a built-up base, 15 to 18 inches above the ground, and in such a position that the air- holes on the two sides are in the direction of the prevailing wind. No artificial blast is employed ; the average Indian has time enough to await a favorable wind. The fuel used is a good quality of charcoal, charged in alternate layers with the ore in the proportion of about I to i. This is a very high fuel consumption, but is sufficiently accounted for in three ways : First. By the great altitude of the regions where the Huairachina is used — from 13,000 to 14,500 feet above s^-level. A PRIMITIVE SMELTING-FURNACE. 9 It is well known that the percentage of fuel increases rapidly with the altitude, that is, with the rarefication of the air. Second. A heavy charge of fuel is often made necessary by lack of a proper quantity of galena to flux easily. Third. The small size of the furnace is naturally against economical working; the heat must be maintained by what would be considered commercially as a ruin- ous consumption of fuel. The materials treated are galenas, as well as zinc-blende and pyritic combinations, and those containing the high-grade sul- phides, such as ruby silver, gray copper, silver sulphide, etc. Ar- gentiferous galena is smelted alone without flux, and is itself used as a flux for the other base combinations or dry ores, by mixing with the latter. The proportions vary greatly, without much re- gard to regularity of working, though the galena generally forms about 50 per cent, of the ore charge. The main point with the Indian is that his flux shall run well in silver (have "ley"), so that when he has sufficient galena at hand he loses nothing by a generous admixture. High-grade galenas are much prized, and are often transported long distances to mix with the more intract- lo THE QUARTERLY. able sulphurets. In the absence of galena, " asendrada " is used for fluxing ; this is an impure litharge obtained from the native cupelling furnaces and always carrying some silver. In preparing the ore for the furnace, it is broken to about pea size and well mixed with the flux. This would appear to be a very crude method of smelting, but, upon the whole, the results obtained are fairly good and attest the skill of the native operator. An occasional bit of only partially smelted ore is, however, sometimes to be seen in the old slag dumps, and the slag itself runs rather high in both silver and lead. I am informed by Mr. James Pascoe, of Potosi, Bolivia, who has made a number of analyses of samples taken from old slag piles, that the latter often run as low as 6 to g ounces of silver per ton, though he obtained one assay of as high as 30 ounces. It must be remembered that the capacity of the furnace is extremely sgiall, say from 50 to 150 pounds of ore in twelve hours, depending upon the force of the wind and the tractability of the ore, and that, therefore, only rich, carefully selected material is worked. The Huairachina was in use by the Quichua Indians under the Inca rule, when the Spaniards first entered Bolivia. It is certain that they existed in considerable numbers at the large mines then being worked in the vicinity of Porco, where, indeed, many of them are still used. They may be seen set upon the low hills about the little town near the old mines, wherever there is an ele- vated spot exposed freely to the wind. In 1545 the Cerro Rico de Potosi (Rich Mountain of Potosi) was discovered, about 30 miles from Porco, and the Huairachina was immediately introduced, forming for years the chief means of extracting the silver from the ores of these wonderful mines. It has been estimated that, between 1545 and 1572, not less than ^250,000,000 worth of silver was produced at Potosi from these furnaces. But, as the rich surface ores were exhausted, the little wind furnace had to give place to the amalgamation process. The Indians about Porco, who still adhere to its use, make a scanty living, either by working stolen ores or by sorting over and re-sorting the old waste dumps of the mines which formerly were so productive. With infinite pains and labor they collect small bits of good mineral which have escaped attention, or which, at- tached to large pieces of barren rock, may have been thrown upon the dumps as worthless. DETERMINING NITRATES IN POTABLE WATERS, 1 1 METHOD FOR DETERMINING NITRATES IN POTA- BLE WATERS BY THE USE OF SODIUM AMALGAM. By EDWARD W. MARTIN and WILTON G. BERRY. Having had occasion to make many determinations of the amounts of nitrates and nitrites in potable waters, we have hereto^ fore used the method of Gladstone and Tribe — the zinc-copper couple. As this, and many other methods are based upon the action of the nascent hydrogen produced, it occurred to us that sodium amalgam might be advantageously substituted for the zinc- copper couple, since the amount of nascent hydrogen produced would be greater, bulk for bulk of the reagent, and moreover only salts of metals identical, or essentially identical with those con- tained in the Nessler reagent would be added to the water under examination, so that the tint for reading could be more satisfactorily compared with that obtained in the standard comparison solu- tions. In this connection we may perhaps be permitted to insert a few references to some of the most important papers on methods for determining nitrates, which though unfortunately very incomplete, may prove of service. I. — Conversion of nitric acid into ammonia. — F. Schulze, Chem. Centr., 1861, 657, 833 ; Zts. Anal. Chem., II., 300; Wolf, ibid,^ 1862, 379; Harcourt, Jour. Lond. Chem. Soc, XV., 385; Siewert, Am. Chem. Pharm., 293 ; Leeds, Proc. Am. Chem. Soc, III., 150; Mactear, Chem. News. XLL, 16, 43, 52, 67 ; Williams, Jour. Lond. Chem. Soc, XXXIX., 100; Ormandy & Cohen, /^/rf., LVIL, 811 ; Ulsch, Fres. Zts. Anal. Chem., XXXI,. 392; De- vada, Chem. Ztg., XVI., 1952. To these may be added reduction to nitrite, and determining the same, Boyer C. Rend., CX., No. 18. II. — Reduction to NO, and reconversion to HNO.3 — Schlosing, Ann* Chim. Phys. [3]. XL., 479; Reichardt, Landw. Versuch. St., IX., 14, 150; Bochmer, Fres. Zts. Anal. Chem., XXII., 20. III. — Reduction to NO, and eudiometric estimation. — Crum, 12 THE QUARTERLY. Proc, Phil. Soc, Glasgow, 1848, 162; and Am. Chem. Pharm., LXIL, 233; Frankland and Armstrong, Jour. Lond. Chem. Soc, XX., 67 ; F. Schulze, Fres. Zts. Anal. Chem., 1870,401 ; Kal- man, Dingl. Polyt. Journ., CCLXXL, 47 ; Bailhache, C. Rend., CVIII., 1 122. IV. — lodometric methods. — De Koninck and Nihoul, Zts. An- gew Chem., 1890,477 ; McGowan, Proc. Lond Chem. Soc, No. 97. V. — Oxidation of indigo solution. — Marx, Fres. Zts. Anal. Chem., 1868, 412 ; Trommsdorf, ibid., 171 ; Goppelsroder, ibid., i ; van Brummelen, ibid,, 1872. 136; Finkener, Rose's Analyt. Chem. [6], II., 830; Fischer, J. pr. Chem., 1873, 57. VI. — Special Reagents (colorimetric) : Resorcinol, D. Lindo, Chem. News, LVIIL, 176. Carbazol, S. C. Hooker, Am. Chem. Jour., XL, 259. Phenol Sulphuric, Grandval and Lajoux, vid, Chem. News, LIII, 97. Pyrogallicy Rosenfeld, Fres. Zts. Anal. Chem., XXIX., 661. Naphthylamin^ Harrow, Jour. Lond. Chem. Soc, LIX., 320. Diphenylamin, Miiller, Chem. News, LXL, 100. Diphenylamin, Kopp, Berichte, V., 284. Naphthoic Hager, Pharm. Centrh., XXVI., 353. Paratoluidin Sulphate^ Long, Fres. Zts. Anal. Chem., XXIII., 350. Brucin, Kersting, Am. Chem. Pharm., CXXV., 254. Cinchonatnine^ Arnaud, vid, Chem. News, L., 103. It may not be altogether outside the scope of this list to give also reference to Griess* tests for nitrites; meta-diamido benzol, Berichte, XL, 621 ; and Naphthylamin, ibid., XH., 426. As potable waters contain more or less organic matter, experi- ments were made with Croton water, which contains both dissolved and suspended organic matter, in the proportions often found in most waters. As the primary object was the use of the test upon Croton water, that water was especially adapted for our purposes. A standard solution was prepared as follows : 1. Strong Solution, — Dry NaNOj, 0.06 grammes: Distilled water, free from NH3, 100 cc ; i cc. = 0.0006 grammes Na NO3. 2. Weak Solution. — Strong solution, 5 cc. ; distilled water free from NHj, 995 cc ; 50 cc. = 0.00015 gm. NaNOj; =0.0003 gm. NH3; = 0.030 mgm. NH3. DETERMINING NITRA TES IN PO TABLE WA TERS. 1 3 The correctness of this solution was proved by reduction to XH3 and colorimetric tests with use of Nessler solution. Our first experiments were chiefly directed to determining the time necessary for the reduction of nitrate to ammonia. Lots of 50 c.c. each of Croton water, found by check tests to contain ni- trates in quantity to aflford 0.03 mgm. NH3 each, were reduced with sodium amalgam and tested, with results as appear from the table. So.' eg After reduction. Newsier added. E .0 2 e ^« Remarks. I None, comin. Present. Not filt. Cloudy. Could not read ; not red'd. 2 " 30 " 3 ** 60 " 4 H^CjO^ 20 " 5 - 30 " 6 *• 60 *• 7 None. 30 " 8 " 60 •• Decided. •« <i L 9 10 1 1 u it I Cloudy, turn'g bl'lc (f u ** act'n more rapid. « (I (i Cloudy. " Cu gauze ad'd. Filtered!. I Clear. o.02oMg Easily read; not quite red'd " 2 h'rs Faint. i< None. " 0.025 «• ** 0.026 " " None. NoNHgimp'tdbyam'lg'm <« The experiments were conducted at the ordinary temperature of the laboratory. Kxperiment 1 1 was only a blank test to prove whether ammonia or anything else giving color with the Nessler reagent was added to the water by the action of the sodium amalgam. The other tests (since confirmed by many others) tend to show that the re- duction to ammonia is incomplete unle.ss fully two hours or more are allowed for the action of the amalgam, and some acid is added ; in any case, that the action of the amalgam affords a cloudy solu- tion, which requires filtering before a satisfactory test can be made with the Nessler reagent. When filtering was used, it was done through a filter paper washed until the washings gave no reaction whatever with the Nessler. 14 THE QUARTERLY. Another set of experiments was then made, using Croton or standard NaNO, solution (weak) in such amount that each experi- ment should show a known amount of NH3. The bulk of solution was in all cases 50 c.c. In these the solutions were all filtered after reduction, the necessity for that step having been made evi- dent by the first series. With a view to shortening the time required for reduction to ammonia, in one case (Experiment 14) the water was slowly passed through a column of the sodium amalgam. The results, however, indicated that this plan was not altogether satisfactory. By way of comparison the Zn-Cu reduction was tried both on natural water and on some of the standard solution (Experiments 17 and 18). The results in those experiments were higher, but under the cir- cumstances we are constrained to regard the sodium amalgam method as the more correct, and in the matter of time (and ma- nipulation, if one distils after the Zn-Cu treatment) it is much preferable. From these and similar experiments we draw the following conclusions : 1. Reduction is best effected by means of sodium amalgam in a Nessier tube, or one having such proportions that the evolved • hydrogen passes through a considerable stratum of the water. 2. The water tested should be acidified (concentrated hydro- chloric acid was found to be most suitable for this purpose). 3. Not less than two hours' reduction is necessary. 4. After reduction, the solution must be filtered before Ness- lerizing. 5 By the amalgam method lower results may possibly be ob- tained than by the Zn-Cu reduction, and Nesslerizing without distilling, but the results go to show that more accuracy is attained. The method we have adopted is as follows : Rinse a 100 c.c. Nessier tube with the water to be tested, and then fill to the 100 c.c. mark with the water to be tested. Drop in 5 to 10 grammes of freshly prepared sodium amalgam, the amount varying with that of the nitrates presumably present. Enough should be added to keep up the action at ordinary tem- peratures for two hours. Cover with a watch glass, and allow the tube to stand in an atmosphere free from ammonia vapors, after adding one or two M y -a' • - 3 o 2 c o o •© c <J — I 5 = o I/. eu) &£UtX>bAU:t£bfib£b£0£tAbiD&Ab«tJO 'uoimio^ 1 E ESEEEESSEEEEESE at vi uotuuiy o « « V u-jO too w^toO */^0 too tnO to • * >• ^ ooooooooooooooo JO lunoiuy O O !}£ bC us tX OOOOOOOOOOOOOOO bfl ? bfi b£&i3b£bi:b/)b£Ub£t£b£b£tJCbi&iObiO *j3issaf^ Xq V g w^E E E E E EEEEEEEEEEEEEEE ps'jiiBxqo vtuotn c o ■M « o N CO W-* O 5 •* <^ 't ro »o w " » O tn to O to to (, to o '-o OOOOOOOOOOOOOOO -niy JO junoiuy >:; o O O O O O 1 o P P.. m O o 6 6 o d o d o 6 d d o o o 0* d • • j^ >k^ s o -c « o 3 o c 3 u >•««« w-av-v^v^^vam^ Si X >N 3 - 4> • a t: *rf ■3 U o. 9 .c ,c ' < O cy5 s o C/3 1 • T3 rt M Wh *^^ O ^ c « «:>> o i ^ eiS (/: ^-« rt 1- cd n : Ts * '« *• « ^ ^ a 4J « " BS '•^ w- ««• 0£ C 1 bA O D - t» ae E • mm colum filter fi • es < 2 bd s o 2S 1 'O .c: 1> • •^ •^ 2: "w <^ 1 V ^ '^- • «■■ {/■ M u, J« P a.x •ajiijJN 4) V A' 9^ U S^ Q Q ^ «• *« ^ « ' p33np9J aoiii o N E § o^ 9 O 00 s O u O • • c O • • c p -pappe ppy X O c o i-! O a 5 O o U « « w « « « « « : 3 E — K - • • E - - c« s c« •p3*jn &A « <• <« O , bA « ^ « •• « « • « « iQdSy 3upnp«^ E < « w ^ w c5- E < « « <• « c ^O • c _o • c o *oodn 4j "o • 73 "1 _2 p^xuauiii^xa uoimios • « « <• « « C3 o , 3 S 3 : 3 3 3 3 3 3 3 6 ^ s d C3 Cj *« ^^ ^rf « C/5 CO OS rn "^ lOvTJ t^cc •OK dxg OS ^ N "^ ^ »0 •• M M M M »« «« M w N N N N « N <M N N r^ ro ro m f^ C'^ i6 THE QUARTERLY. drops of concentrated HCl (free from ammonium salt). After two hours,* filter through a small filter previously freed from all traces of ammonia, and Nesslerize 50 c.c. of the filtrate. Deduct free ammonia (found by another operation) and calculate results. N. Y. Health Dept., June, 1893. PRESENT CONDITION OF TFTE MECHANICAL PREPA- RATION OF ORES IN SAXONY. HARTZ AND RHENISH PRUSSIA. BY M. MAURICE BELLOM. (Continued from Vol. XIV., p. 349.) VI. — Treatment of the Slimes. [a) Method of Treatment. — The slimes — that is to say, material less than 0.25 millimeters in size which has been separated in the classification of the sands — is submitted to a treatment in two operations, the first consisting of a sorting in water currents, and the second of a separation by specific gravity. A. The apparatus used for the preliminary classification are labyrinths, pointed boxes and the Meinicke spitzlutten apparatus. Sizing by trommels is used exceptionally in connection with pointed boxes at Saint Andreasberg (Hartz), as will be described later. B, Separation by specific gravity is effected upon ordinary fixed tables, sweeping tables, belt tables, longitudinal bump tables, Rit- tinger tables, revolving tables, round buddies and the Linkenbach table. The first two types of tables do not justify further men- tion. Belt tables are represented in Saxony by a recent type, the Stein table, which will be described later. Longitudinal bump tables, which, as we have seen, are used by some engineers for the treatment of sands, are not to be recommended for the treatment of slimes. In treating such fine material the swing of the table or force of the blow must be lessened. This diminishes the capacity of the tables, and thus exaggerates the disadvantage already noted * The solution should now be only very faintly acid ; if decidtdly acid, add more amalgam and continue the reduction. MECHANICAL PREPARATION OF ORES. 17 in the treatment of sand by this apparatus. Furthermore, the set- tling to which the slimes are subjected interferes with a perfect separation of the minerals. These disadvantages, which have been noted by the chief engineer of the Henry mines {Annaies des Mines, Series 6, Vol. XIX., iS/i.p. 358). have not prevented the Lauren- burg engineers from continuing the use of these tables. The rea- son may be found in the facility with which they may be applied to dressing operations such as those of La u renbu rg, , where the frequent variations in the composition of the ore to be treated have led to the adoption of non-continuous work, A further advantage consists in the ease with which they lend themselves to the retreatment of material which varies with the nature of the products to be treated. The Rittinger table, which enjoyed until recently such popularity that it was considered as a necessary element of all mechanical preparation, has found in the Linken- hach table a formidable competitor. A comparison of these two tables Will appear later in connection with the description of the Linkenbach table. Revolving tables, the work of which is re- garded as satisfactory, are now considered as inferior to fixed tables, on account of the oscillations which the rotation of the washing sur- face cannot fail to transmit to the material under treatment. This defect is sufficiently marked to lead to the adoption of the round buddle (which, in general, is regarded as an inferior appa- ratus lor the treatment of slimes) on a large scale in the recent workshop at Weiss. Also the success of the stationary table of Mr. Linkenbach may be similarly explained, for, by substituting adjustable jets of water for the brushes of the round buddle, has given to this last apparatus the precision which it lacked, without losing for the new table the advantages which the fixed surfaces present for the delicate washing of the' fine materials. It should be added that the convex form for washing tables is now preferred to the concave form, which causes higher losses. At the same time, in the case of superposed tables a concave form is generally adopted for the highest tables, with a view to facilitating the super- intendence of the work upon the lower tables. In the superim- posed Linkenbach tables they have, however, by discarding this form, preferred to sacrifice the facility of access to the lower tables to the reduction of the losses in the treatment. {^) Apparatus — /°. The Miinkke Spitzlutten Apparatus. — The Meinicke spitzlutten apparatus is contained in a cylindrical sheet- VOL XV.— 2 i8 THE QUARTERLY. iron vessel with a funnel-shaped bottom. The material to be sepa- rateid enters the upper part of the apparatus by the trough, a, and the funnel, b, which empties into the pipe, r, contracted at its upper end. The channel, ^/, limited by the surfaces of two truncated cones, re- ceives, in its turn, the material, and carries it to the annular space. /, where it rises to descend again over the upper side of the outer en- velope of r, into a second annular space, e^. At the lower part of this last the slimes enter the duct, d^^ the form of which is analogous to that of r/|, and which conducts it into the space e^^ where it fol- FiG. 27. Fig. 2S. General View and Section at A B. Scale -^^, lows the ascending path as in the corresponding space, f,. The annular trough, /, which surrounds the apparatus, receives the slime and carries it to the trough, /j. Envelopes concentric with those which limit the spaces, r, and and d^ on one side, e^ and d^, on the other, determine in each of these spaces subdivisions. gxJhJ^x and g^, h^, h^\ which terminate, the first one in the space /'i and the second one in the space /g. The space /'i communicates with the emptying pipe, k^, and the space i^ with the corresponding pipe, k^ The water for washing is carried into the first of these two spaces, i^ and i^^ by the pipe /,, and the second by the pipe 4. The prolongations ///' and //j" put the ducts //j and //j, respectively, in communication with the spaces c^ and ^2- From thence the heaviest grains (that is to say, the first MECHANICAL PREPARATION OF ORES. 19 class) descend from the annular space, e^, by g^, A[ and A/ into the space i^. whence they are carried off by the pipe ky. The second class of slimes proceeding from e^ is collected by itself in the space i^ from whence it is taken off by the pipe i,. Lastly, the third class — that is to say, the lightest — is received in the annular trough f, and is carried off by the current which comes out of the appa- Fio. 29. Horiionlal Sectioi Vertical Section. Ficja. Enlarged Vertical Section. ratiis. Grains of a given size always carry with them in their de- scent finer grains belonging to the divisions which follow them, and it is with a view to eliminate these last that two currents of water are introduced, one by the pipe /, and the other by the pipe /j. The water encounters the grains of the corresponding class in their descent, and carries off the lighter slimes by the ducts /i,' (and A,") into the spaces <r, (and r,}, and from thence into the fol- lowing channel, where they mix, in their descent, with the grains 20 THE QUARTERLY. of the next inferior size. The ducts //j, h^ may either surround the apparatus, or, on the contrary, be divided into a series of distinct conduits, a, a\ tf" . . . . limited by the curved sheets, m. Fig. 33. Thisdivision may likewise in this case be applied to the ducts /// and //j', A/' and h^\ In this way economy of water is effected. Otherwise, the water would have to enter the duct A/ or //j') with a velocity greater than that with which it flows out of the duct ///' (or h<l'^, or inversely; consequently, it only remains to choose the dimensions of the sections of the ducts /// and///' (or h\l and ///'). In all cases it is necessary that the ducts //„ A/ and ///' (or /j^, h^ //g") have the same section at their point of juncture. The details of this apparatus, which Mr. Meinicke put in ser- vice for the first time in the month of August, 1888, in the works of Clausthal, are given in the following table in which they are designated as follows : D = the outside diameter of the cylindrical part. //j = the difference in level between the upper side of the funnel, b, and the bottom of the trough,/i. //g = the difference of level between this same surface and the outlet oc of the pipes, Ki or Kg. //g = the difference in level between the outlet o and the lower extremity /5 of the truncated conical part. Values of D, in millimeters " " hj, " " " hj, " " hj, «• Slimes treated per minute (in litres). IIOO 350 750 IIOO 1400 350 850 1350 200-250 300-400 • The Meinicke spitzlutten apparatus, by reason of its annular form has the following advantages over other apparatus of the same kind ; 1. The subdivision of the slimes between the various compart- ments is perfectly symmetrical, the products entering along the axis of the apparatus and passing thence from cell to cell to the periphery. 2. The clarification of the slimes, under the influence of the MECHANICAL PREPARATION OF ORES, 21 pure water distributed by the pipes, /j and Ij, also operates in a symmetrical way starting from the axis of the apparatus. 3. The apparatus, each compartment of which envelopes the preceding one, occupies comparatively much less space than the old style apparatus constructed on the same principle. 4- Lastly, the annular form allows of placing inside the appa- ratus the mediums of clarification, which in ordinary sorters, are relegated to the exterior and are consequently more cumbersome. The only works where up to the present time this apparatus is found, is that of Clausthal, where it gives very satisfactory results. At the same time there is no doubt that these results would have been better, if it had been used in conjunction with apparatuses better Btted than the Meinicke sand-sorting apparatus, for washing the sands treated at Clausthal (see note on page 349, Vol. XIV.). If a spitzkasten or sand-sorting apparatus had been used, better general results would have been obtained and the advantages of the spitzlutten apparatus would have been more clearly shown. Meifturke Distributer. — Mr. Meinicke has completed the spitz- lutten apparatus by a distributer (schlammaufgabevorrichtung), of which the following figures represents two types of slightly different dimensions. The materials to be distributed in the spitzlutten apparatus are charged in a cylindrical receiver, a, at the centre of which turns the axis, b, which carries a knife, c, and above a perforated pipe, d, which furnishes a spray of water. The endless screw, e, and the toothed wheel, /, transmit to the axis, b, the movement which the axis of the endless screw receives from the pulleys, P. The filet which carries the extremity of the axis, b, determines the descend- ing movement of the axis, b, as soon as that of the nut, A, is stopped. The stoppage of this nut, A, is effected by tightening the nut, /, which stops the movement of the pinion, «, and therefore that of the toothed wheel, O, which engages with it. This wheel, O, is lowered by the nut, //. The portion fileted, g, has a longitudinal groove, k, in which an angular wedge is fixed at the interior part of the nave of the wheel, /. The knife (c) describes a spiral surface and cuts off a thin slice of the material, while the water led by the pipe {d) secures disin- tegration. The exit of the products is effected by the opening (/) made in the vertical axis, the horizontal section of which is given on the right, Fig. 39. The knife having arrived at the bottom of 22 THE QUARTERLY, the receptacle the straps giving motion are raised, which work the Fig. 34. Fig. 35. O M>1M^ Fig. 36. rj TV Three Projections of a M einecke Distributer. Fig. 38. Fig. 39. -.^'m^//' •',/,/*r////t/'A-AV//».//ir//Vtim^-//y)i^^m/f^/^i*'ir/.. Vertical Section, Axis and Horizontal Section of Meinecke Distributer of Second Type. blocks, Pp then loosen the nut (/) and by turning the crank (»/) MECHANICAL PREPARATION OF ORES, 23 detertnine the rotation of the \ inion («) and then the knife can be raised to its former position. The apparatus is then ready to start again. The water necessary for the operation enters by the pipe (^) in the annular reservoir (q) which takes place at the rota- tion of the axis (^). If this axis is hollow, it can be utilized as a pipe for the water. It is easy to make the pipe {d^ work only at the f)oint of rotation, and not at the descending movement of the axis. The only essential condition in setting up the apparatus, is to place it sufficiently high and to furnish it with an elevator, for the material which it should distribute to the following pieces of apparatus. In the absence of an elevator in the works at Claus- thai, the schlamms are shovelled into the Meinicke distributer. This inconvenience which could be easily remedied is one of the reasons for the Meinicke apparatus not finding favor at Clausthal. The parts of the apparatus are summed up in the following table, where they are designated as follows : D, the exterior diameter of the cylinder, a, H, its height. A, the difference of level which should exist between the depth of the reservoir, a^ and the superior part of the apparatus for feed- ing. V, the capacity of the cylinder, a. Q, the delivery in litres per hour, told by one turn of the vertical axis b. Value of B, in meters I I 1.5 2 " H, " A-fo.15 A-j-0.20 A-| 0.30I «« A, " I I I I *« V, in cubic meters }i i}^ 3 Q, inlitres 2 4.5 ' 8 Stein-Table. — The following figures show the Stein-belt table : This table consists of a framework formed of two horizontal sills of wood, a, and of two uprights, c, also of wood. On the inside face of the left upright is bolted an iron bump-plate having a groove which serves to guide the pin, e, of the frame of the table ; the piece,/, placed against the inside face of the same up- right, supports the trough which conveys the slimes, and the threaded rod traverses a nut fixed to the upper part of the vertical 24 THE QUARTERLY, post, c, having on its outside fdce the spiral spring, h. The verti- cal post, r, on the right, has, on its inside face, pieces d, /, g. Similar to those, bearing the same letters, but on its outside face, there is a rest, /, which receives the shaft, k^ the cam-wheel with three teeth. /, the movable pulley, w, and the fly-wheel, n, II. — A bunfip-frame, placed between the two uprights, r, and provided on each side with a guide-pin, lo mm. in diameter. The rod on the left has two nuts, one, p, regulates the extent of the shock, and the other, q, placed at the extremity of the rod, regu- lates the tension of the spiral spring, A. The rod on the right deter- FlG. 40. Longitudinal Elevation. mines the displacement of the table by the introduction of a fork, of a lever, r, of a coupling-pin, and of a cam-wheel with three teeth already mentioned. The fram* has two sheet-iron cylinders, 22 cm. long and 22 cm. in diameter; their axes are inclined ^0^ to the horizon; the distance from axis to axis is 67 cm. The posterior part of the axis of the cylinder on the right (Figs. 40 and 41) has a ratchet- wheel, t, 183 mm. in diameter with 56 teeth. This wheel, which is fixed on the axis of the cylinder with two nuts, is outside of the frame. The two pawls, v and w, move between the teeth of this wheel ; the first, v^ is fixed to the slime-trough, the other, iv^ to the movable frame. When the displacement of the frame is equal to f of the space separating two consecutive teeth, the cylinder turns backward MECHANICAL PREPARATION OF ORES. 25 one tooth, and the p:»wl, w, catches in the following tooth and maintains this position during the shock. The cylinder on the left has a cushion on the anterior part, the position of which can be regulated by a screw, and most conveni- Fio. 41. ently distributes the weight of the belt, notwithstanding its incli- nation toward the front. The endless belt, x^ passing over the two cylinders, has a width of 205 mm, ; it is made of rubber. A little wheel placed against Fig. 42. the lower side of the belt, gives it the proper tension ; the upper part passes over a planed surface, a, fixed to the frame, and having underneath two conduits for water, each with three holes for dis- tributing the water over the surface, «, and, consequently, under 26 THE QUARTERLY. the belt, by which adherence to the surface, //, is rendered impos- sible, and wear by friction notably diminished. To secure inde- pendence of the frame, and to allow it to be moved to the desired rnclination. it is suspended by three hooks, m, to the levers, /, screwed to the threaded axis, Zy resting on the uprights, c ; the inclination of the belt is adjusted by the nut s. III. — A conduit, «, placed a short distance from the surface of the table, and supported in the right and left by the pieces, /. Two hooks, J/, join it to the levers, L, and to the axis z, so that it can easily follow the washing belt, whatever be the incli- FiG. 43. Rear Elevation. nation given to the latter. The trough serves to carry the slime coming from the pointed box, M, which concentrates it, by dis- charging the excess of water through the overflow-pipe, T, which flows to the settling-tanks. Four orifices furnished with screw gates allow portions of the slime to go to separate distributors (N), which spread it out in a thin layer. The pointed box (M), for example, receives a slime composed three-quarters of water and one-quarter of solids, de- livers to the table the solid portion constituting one-quarter of the original slime and an equal quantity of water, or another one- quarter of the slime while the rest of the water passes away by the pipe (T). At the end of the conduit {n) (Fig. 40, on the left), there is a reservoir covered with a sieve, and a zinc pipe {q) gives tVi^ u/ater for wetting the belt. MECHANICAL PREPARATION OF ORES. 27 The pipe (Q) serves as an overflow for this reservoir. The com- partments (D) joined to the sheet-iron spouts (F) remove the dif- ferent sorts of minerals separated on the table. The trough (G) resting on the two supports (H) serves not only to sustain the spouts (F), but also to receive the water running to the settling- tubs. This table, therefore, bears the same relation to the Rittinger table as the Hartweg table does to the ordinary bump-table. The ore is spread out as on the Rittinger table, in diverging lines, passing off at the superior angle, where the washed portions are received. This table (used in the works at Himmelfahrt) moves at the rate of 130 shocks per minute; at the end of 53 shocks each grain has traversed the whole surface of the belt. It treats 43 litres of slime per minute. An improvement of this table, introduced at Himmelfahrt, con- sists in the substitution for the compartments, D, of movable divi- sions — therefore more easily regulated — set into the trenches in the ground, which receive the washed products. T/u Linkenbach Table, — Figs. 44 to 48, represent three different types of these tables. The principle common to all is in the sub- stitution of jets of water for the sweeping brooms of the round huddle. The Linkenbach table may be simple or superposed. The simple table, says Mr. Linkenbach, is composed of a convex cone, formed of a covering of cement 8 mm. thick, resting on mas- sive piete of masonry, on arches, on a mass of beton or upon an iron frame-work, wjth a layer of beton 50 mm. thick. Fig. 44 represent respectively a vertical section and a plan of a Linkenbach table 8 m. in diameter; {a) is the table made of ma- sonry, generally covered with an even layer of cement ; [b) is a vertical shaft, rotating the arrangement for the distribution of the products. The shaft is moved by the cog-wheel run by the end- less screw [d) on the main shaft. The discharging apparatus {g), the pipes for the washing (A), and the pipes for washing off the finished product (/) are suspended from the arms [e]. These, eight in number, are bolted to the hub (/), keyed on the vertical shaft (S). The annular gutter {k), rest- ing on these arms, partakes of the movement of rotation. The fixed pipe (/), provided with a stop-cock, gives the water required for washing. The fixed pipe {rri) conveys the slime; it follows the canal {ti) ; 28 THE QUARTERLY. then rises vertically up to the circular trough (u) of the distributor, into which it empties. The distributor is composed, independently of the channel for the slime, of a compartment for distributing the slime, and of another which gives the water for washing. The Fig. 44. and Plan of Linkenbach Table. Scale {^,. pipes {^) lead the water from the gutter {k) to the different noz- zles. The fixed side gutter {_q) is composed of three concentric compartments of the same size, of which {<]'), nearesl to the table, receives the tailings, \q") the middlings, and the last {/j'"\ at the exterior of the table, the finished product. MECHANICAL PREPARATION OF ORES, 29 The removal of the interijiediate and final products from the table to the compartments corresponding with the side channels, is obtained by means of the apparatus {g) suspended from the arm {/) and moved by the rotatory motion. The apparatus (g) is composed of a circular apron formed of round gutters, which surround the outer edge of the table. This apron has plates of zinc fastened to it which overlap each other, they serve to remove the intermediate products, before coming to the compartment (^") while the plates used in like manner, for the finished products should be prolonged as far as the exterior com- partment (^"'). The passage of the waste products in the com- partment (^'), next to the table, takes place without the aid of the apparatus (g), which is not furnished with plates of zinc above the corresponding compartment. The canals (r") and (/^") respec- tively conduct the products from (^") and (^'") to the settling- tanks, one for the middling the other for the finished products ; the canal (r') which runs from the compartment (^') directly to the settling- tanks for tailings. This table is generally operated in the same manner as the ordinary round tables. The slime flows over three-eighths of the surface of the table ; four-eighths are occupied by the ** interme- diates," and one-eighth by the finished products. This division of surface may be modified ; it being sufficient to change the relation established between the compartment for the slime and that of the water for washing in the distributor, and to provide the discharg- ing apparatus with plates of zinc of the right size. If it is desirable to obtain two sorts of finished products on the table, the canal {q) should have an additional compartment, in place of one, for receiving the new sort, and the apparatus {g) provided with plates of zinc of the proper size, for removing these products to the compartment for receiving them. Also for the washing and sweeping off of the second finished product, a mova- ble pipe for sprinkling the lower layers on the table, and after the removal of the second sort a larger pipe introduced for sweep- ing away the second sort of intermediate products, which are richer. This second class of middle product is generally sent to the compartment of the side canal {q) which receives the first middle product, and these two are treated together. Figs. 46 and 47 give another arrangement of the Linkenbach table. This table is 7 mm. in diameter, and yields two kinds of 30 THE QUARTERLY. finished products, and the trough surrounding the circumference of the table at that time contained three concentric compart- ments. The surface of the table is made like the preceding, but there are essential differences in the arrangements for ro- tating the distributor, and for the discharging apparatus for lead- Fio. 46. Vertical Section and Plan or I,inkenb»eh Table. Scale ■, jj. ing the washing-water and for the removal of materials. The hollow axis \b) is joined to the pipe which supplies the wash-water by the stufRng-box {d). The distributor (c) is suspended from this axis and the tube {g) leads directly into it, the slimes coming from the spitzkasten. The discharging-gutter (/;) fixed on an armature is carried by the rollers (/') placed on a circular track MECHANICAL PREPARATION OF ORES. 31 {k) ; it is composed of twenty- four equal and distinct segments, each being provided with a discharge-pipe (/). The pipes (/) vary in length, depending upon the nature of the product which they are to conduct to corresponding compartments of the empty- ing-trough. The pipes of different length replace the sheets of zinc used for the same purpose in the preceding table. The arms (;«), four in number, are formed of gas- pipes firmly joined at one end with the armature yNhvch carries the discharging- trough, and at the other end to the vertical shaft {b) whose interior communicates with the pipes {m). The pipes for washing {n) («') and those for removing the final products {o) (^') are fixed to these arms ; they can be removed at pleasure, like the first. Rotatory motion is produced by means of the chain, S, which passes over the pulley (q) and over the groove on the outside of the armature which carries the discharging-trough ; this chain at its other end passes over the pulley (/) fastened on the main shaft. This arrange- ment gives the necessary tension to the chain. The four arms (w) transmit rotatory motion to the hollow shaft id) and to the apparatus for washing. The work on this table is the same as on the preceding. Except the waste products which go back to the settling-tubs, the products obtained are collected in the tanks for the middlings, («) and in the tanks {«') {n") reserved for the final products. In large dressing-works, each class of slimes classified according to falling ratio should go to a special table. In most works, in order. to obtain a regular classification, three kinds of slimes must be produced, which render necessary the employment of three kinds of tables. Whenever the space permits, simple tables should ' be used similar to those described, but if this arrangement is impracticable on account of lack of room, two, three, or even more tables, may be mounted on the same axis, which, like the simple table, wash separately a separate class of slime. Fig. 48 represents the arrangement of three superposed Linkenbach tables ; each give some merchantable galena and blende, as if the others did not exist. Similar products furnished by the super- posed tables are reunited in the same conduit. The upper Jtable has a diameter of 6 m., the intermediate 6.5 m., and the lowest 7 m. The surface of each table is formed of a layer of cement 80 mm. thick; the upper part is perfectly smooth. This layer rests upon an iron armature [k), with eight arms, which, 32 THE QUARTERLY. for the lowest table, rests all around upon a pier of masonry, and for the other tables is supported by eight cast-iron uprights (/). The upper table receives the coarsest material, the lowest the finest, and the middle table the intermediate size. The tables arc fixed; the only moving parts are the hollow axis {b\ the distribu- tors (c) ((■') {c"). which are fixed there, so that the washing-pipes (d) (a") (<^") and the sweeping-pipes for the products (c) (t') (^"), Fig. 4S. . Seclion of Three Siiperpi^d Linkenbach Tables. Scale (Jj. and the discharging-gutter (/"} of the lowest table take part in this movement; on the contrary, the gutters (/) {f) belonging to the two other tables are fixed. The pipes {g) [jf) (^") carry the three kinds of slimes. The work on the table is conducted in the same way and by the aid of the same preparation as on the separate tables. The various products obtained on each table are emptied into the side canal (A) [placed under the lowest table only] by the introduction of the gutter (/") carrying the pipes (/), which may vary in length. The products from the lowest table go directly back; those INDEX TO LITERATURE OF DIDYMIUM. 33 from the other two tables are first received in the fixed trough which surrounds its corresponding table. The bottom of the fixed gutter is composed of a series of funnels placed side by side, the points being cm. 60 apart, which discharge into pipes, by which the products from the highest table flow into the fixed gutter of the intermediate table, whence the correspond- ing products from the two upper tables flow together into the movable trough (/")• ^^^ movement is effected in the same way as for the simple table. (To be continued ) INDEX TO THE LITERATURE OF DIDYMIUM— 1 842- 1 893. By a. C. LANGMUIR. The following paper is offered to chemists with the hope that it may be of some value to them in their researches on an element of great theoretical and scientific interest, particularly as an ex- ample of the wonderful results accomplished by the use of the spectroscope in modern chemistry. The voluminous literature of didymium affords a striking illustration of the pursuit of science for its own sake, and with no reward beyond the satisfaction of having advanced the cause of truth. Original work, at the present time, must always be preceded by a long and painstaking search through the literature, which con- sumes no inconsiderable amount of time. Anything which can lighten the labors of the investigator in this direction is sure to be a welcome addition to the literature. In 1882 Dr. H. Carrington Bolton originated the idea of indexing the literature of each of the chemical elements, and a Committee on Indexing Chemical Literature was formed. The committee annually reports the progress made during the year, the reports being published in the Chem. News and American journals. The following elements have been indexed : Columbium. — Index to the literature of, 1 801-1887, by Frank W. Traphagen, Smithsonian Miscellaneous Collections, No. 663, Washington, 1888. VOL, XV. — 3 34 THE QUARTERLY. Iridium. — Bibliography of the metal, 1 803-1885, by N. W. Perry, in Mineral Resources of the United States, 1883-1884, p. 588; School of Mines Quarterly, 1885, p. 114; Chem. News, 1885, 51, p. 32. Manganese. — Index to the literature of, 1596-1874, by H. C. Bol- ton, Annals of the Lyceum of Natural History, New York, Vol. II., Nov., 1875. Titanium. — Index to the literature of, 1783- 1876, by E. J. Hal- lock, Annals of the New York Academy of Sciences, Vol. I., Nos. 2 and 3, 1877. Uranium. — Index to the literature of, by H. C. Bolton, 1 789-1 885, Smithsonian Reports for 1885, Washington, 1885, p. 919 -946. Vanadium. — Index to the literature of, 1801-1876, by G. Jewett Rockwell, Annals of the New York Academy of Sci- ences, Vol. I., No. 5, 1877. The general plan of the following index corresponds with that of the others published. The indexes at the end of every volume of each journal were consulted, unless an index covering a series of years was available. The French journals proved to be very troublesome in this respect, as indexes at the end of the volume are often omitted, and the general indexes are seldom detailed enough to be of much value. This was especially true of the Bull. Soc. Chim. and the Ann. Chim. Phys. The abbreviations used are those given by H, Carrington Bolton (and others) in Chem, News^ 1887, 56, 272, INDEX TO LITERATURE OF DIDYMIUM, 3S Index to the Literature of Didymium. Ehitc. Author. 1 842 Mosander . . Discovery . . Remarks. 1843 Mosander . 1843 .L. Bonaparte 1845 1849 Hermann . . Marignac . . Researches . Separation from cerium. Existence of Di. doubted. Separation from cerium & lanthanum. Atomicweight 1S50 1853 H. Watts . . Marignac . . •iSep'r'tion fr'm cerium and lanthanum. Separation from lanthanum. Atomicweight Cop pounds. 1856 1857 Marignac. . Gladstone . Crystalline f'm of sulphate. Optical test. Ann. Chem., Liebig, 44, 125. Ann. der Phys., Pogg., 56, 503. Pharm. Centrbl., 1842, 793. J. de Pharm., 1843. 143. Berzelius' Jsb,, 1844, 144. J. Frank. Inst. [3]. 5, 411. Am. J. Sci., 43, 404. Phil. Mag. [3], 23, 241. Ann. Chem., Liebig, 48, 210-223. J. prakt. Chem., 30, 276-288. Ann.derPhys.,Pogg.,6o, 299-31 1. Ann. chim phys., [3], 11, 464. Compt. rend., 16, 1008. J. prakt. Chem., 29, 268. Pharm. Centrbl., 1843, 7^9- Berzelius* Jsb., 1845, 115. Ann. der Phys., Pogg., 59, 623. Chem. Gaz., 1843, 4^5. Chemist, Watt, 4, 293. Am. J. Sci., 46, 206. J. prakt. Chem., 34, 182. iBerzelius* Jsb., 1845, ^^5- I Arch. ph. nat., 11, 21. Ann. Chem., Liebig;, 71, 356. lAnn. chim. phys., [3J, 27, 209. J. prakt. Chem., 48, 423. I Pharm. Centrbl., 1849, 837. '.Chemist, Watt, 1849, 20. .Chem. Gaz., 1849, 329. Ijsb., 1849, 263, 265. 'J. Chem. Soc, 2, 140. Pharm. Centrbl., 1849, 892. Ann. chim. phys., [3], 38, 148-177. J. prakt. Chem., 59, 380-406. Arch. ph. nat., 24, 278. Ann. Chem., Liebig, 88, 232. J. Chem. Soc, 6, 260-273. Chem. Gaz., 1854, 141-148. Am. J. Sci. [2], 16, 413. Jsb., 1853, 346-343- Compt. rend., 42, 288. Pharm. Centrbl., 1856, 179. J. Chem. Soc, 10, 219. J. prakt. Chem., 73, 3S0. Am. J. Sci. [2], 25, 100. Jsb,, 1857, 568. 36 THE QUARTERLY. Index to the Literature of Didymiiini — continued. Date. 1859 i860 i860 Author. Remarks. References. 1861 Marignac ... Compounds. Stapff. . . . . Sep'r'tion fr'm Hermann . . . Nordenskiold.l Crystalline form of oxide. Ann. min. [5], 15, 272. Jsb., 1859, 138. J. prakt. Chem., 79, 257. lanthanum. ;Chem. News, 2, 196. Researches. Bull, de la Soc, des Naturalistes a Moscow, i860, 4, 543. J. prakt. Chem., 82, 3S5-395' Pharm. Centrbl., i86t, 433-438. Arch. ph. nat., 11, 354. Chem. News, 4, 72-87. Jsb.-, 1861, 195. 1861 1862 1862 1864 1864 Erdmann , . O. N. Rood 1864 1864 1865 Ann. der Phys., Pogg., 114, 618. Oefvers. K. Vet. Acad. Forhandl., i860, 439. J. prakt. Chem., 85, 432. Pharm. Centrbl., 1862, 556. Rammelsburg.' Isomorphism Ber. der Akad. der Wissensch. zii lof didymium Berlin, 1861, 891. with other ,J. prakt. Chem., 85, 79. sulphates. Ann. der Phys., Pogg., 115, 580. Ztschr. Chem., 5, 376. [Pharm. Centrbl., 1862, 25. ,Chem. News, 5, 139. . Absptn spctm. J. prakt. Chem., 85, 394. Absorption Am. J. Sci. [2], 34, 129. spectrum. Ann. der Phys., Pogg., 117, 350. I Chem. News, 6, 140. Popp Separation Ann. Chem., Liebig, 131, 359. I from cerium. Bull. soc. chim., 3, 385. Bunsen .... Absorption |Ann. Chem., Liebig, 131, 255. spectrum. Arch. phy. nat., 21, 384. I Phil. Mag. [4], 28, 246. Jsb., 1864, 108. Damour Estimation Compt. rend., 59, 270. and Deville. and separation I Instit., 1864, 269. I Bull. soc. chim. [2], 2, 339. I Chem. News, 10, 230: Jsb., 1864, 704. Am. J. Sci. [2], 37, 352. Ztschr. anal. Chem., 3, 394. J. prakt. Chem., 94, 123. Bull. soc. chim., 4, 360. . Separat'nfromlJ. prakt. Chem., 93, 106. the thorium earths. Occurrence jChem. News, Z2, 183. in churchite. i 1864 'W.Gibbs. Separation from cerium. Hermann . Williams INDEX TO LITERATURE OF DIDYMIUM. 37 Index to the Literature of Didymium — continued. Date. Author. Remarks. References. 1 86^ Dela Fontaine 1865 Winkler f 1866 Bunsen 1866 Bunsen 1866 1S67 1867 1869 Hermann . Pattison and Clark. Marignac . Zschiesche Absorption jArch. phy. nat., 21, 97. spectrum. Ann. der Phys., Pogg., 124, 635. Ann. Chem., I.iebig, 135, 194. J. prakt. Chem., 94, 303. IZtschr. Chem., 8, 266. |Bull. see. chim., 3, 4x7. Separat'nfromJ. prakt. Chem., 95, 410. lanthanum. Ztschr. anal. Chem., 4, 417. Chem. Centrbl., 1865, 1007. Bull. soc. chim., 6, ^o^. Chem. News, 15, 178. Absorption | Ann. der Phys., Pogg., 128, 100- 108 spectrum. jPhil. Mag. [4], 32, 177-182. Ztschr. Chem., i866, 419. Ztschr. anal. Chem,, 5, 109. Ann. Chem., Liebig, 137, i. J. prakt. Chem., 99, 274. Ztschr. Chem., 1866, 72. Chem. Centrbl., 1866, 118. Ztschr. anal. Chem,, 5, 109. Ann. chim. phys. [4], 9, 487. Bull. soc. chim. [2], 6, 18. Arch. ph. nat., 25, 113. Am. J. Sci. [2], 41, 399. Jsb., 1866, 799. .'Separai'nfrom J. prakt. Chem., 97, 340. zircon earths Chem. News, 16, 259, Ztschr, anal, Chem., 8, 249. Ztschr, Chem., 11, 191. Separation in I Arch, ph. nat., May, 1867, Estimation by means of spectrum. 1869 1869 1870 ITialen Hermann Separation from cerium. aeschynite. Salts; equiva- Measurement of spectrum. Ztschr. Chem., lo, 725. J. prakt. Chem., 107, 74. lent of oxide. Bull. soc. chim., 13, 232. Ztschr. Chem., 13, 40. Ztschr. anal. Chem., 9, 540, Jsb., 1869, 259. Nova Acta Reg. Soc. Sc. Up- sal [3], vol. 6. Ann. chim. phys. [4], 18, 238, .Occurrence in'J. prakt. Chem., 107, 140, > mlBeral kingdem. | Erk Atom'c w*ght. Jenaische Ztschr, Med. Nat., 6, Separation | 299. from lantha- Ztschr. Chem. [2], 7, 101-115. num and jZtschr, anal. Chem., 10, 476, 509. yttrium. J. Chem. Soc, 187 1, 494. .Bull. soc. chim., 16, 84. 38 THE QUARTERLY. Index to the Literature of Didymium — continued. Date. Author. Remarks. References. 1870 W. Gibbs . . . Sulphate . . . Ber., 1870, 858. 1870 Rammelsburg. Occurrence in Ber., 1870, 858. 1 1 1 yttrocerite. 1872 Young . . . . 1 Occurrence in Am. J. Sci. [3], 4, 356. the sun. Jsb., 1872, 147. 1872 Horner . . . . 1 Occurrence in Chem. News, 26, 109, 285. pyromorphite. J. Chem. Soc, 25, 995. Bull. soc. chim., 19, 23. 1 Jsb., 1872, 241. 1872 Church . . . . Didymium in Chem. News, 26, 1^0. 1 British min'ls.j. Chem. Soc, 25, 1075. 1872 i Rammelsburg. Determinat'n J. Chem. Soc, 25, 194. , in tantalites 1 i <V columbites. 1873 Marignac. . . Crystallo- Ann. chim. phys. [4], 30, 56. graphic forms Jsb. rein. Chem., 1873, 57- of salts. Bull. soc. chim., 20, 84: J. Chem. Soc, 27, 25. 1873 Mendelejeff. . Position in Ann. Chem., Liebig,Suppl.,8, 190. periodic sys- Ann. Chem., Liebig, 168, 45-63. j tem. Ber., 1873, 558- J. Chem. Soc, 26, 1004. 1873 Horner . . . . Occurrence in Chem. News, 28, 282. 1 1 scheelite. J. Chem. Soc, 27, 345. Bull. soc. chim., 21, 275. Jsb. rein Chem., 1874, 77. . . de Pharm. [4], 19, 494. 1873 ;Stolba . . . . Salts Jer. der konigl. bohm. Ges der Wissensch, Nov., 1873. I Ztschr. anal. Chem., 13, 59. Jsb. rein Chem., 1874, 77. Jsb., 1873, 260. 1873 Carlson . . . . Plat'nocy'n'de;Ber., 1873, '468. 1873 Rammelsburg. Isomorphism Ber., 1873, ^7- of sulphate • with cadmium 1 1 sulphate. 1873 T^^alen . . . . Spectrum . . . K. Svensk. Vet. Acad. Handl.. 1873, ", No. 4. 1 jBull. soc. chim. [2], 22, 350. | Jsb. rein Chem., 1874, 75. 1874 Frerichs . . . Compounds . Ber., 1874. 798. Separation Ztschr. anal. Chem., 13, 317. from ;Bull. soc. chim., 22, 498. >» lanthanum. J. Chem. Soc, 27, 1062. . Am. Chemist, 5, 264. Remarks. ) TERATURE OF DIDYMIUM. iter attire of Didymiitm — continued. 39 om pounds. Refe/ences. C^2ontinued.) Jsb., 1874, 256. Jsb. rein Chem., 1874, 76. Crystallo- phic invest igations. I^esearches. K. Svensk. Vet. Acad. Handl., 1874, No. 5. Bull. soc. chim., 22, 353. Jsb. rein Chem., 1874, 77. x87 4 Thomsen. 375 Hfllebrand and Norton. ,S75 Cleve xS7S Phillips. ^y^ iBunsen . • • •! 1^75 B^h^'g .... Detection of traces by spec- trum. Atomic w'ght. .jAtomic w'ght. Electrolytic separation from cerium and lantha- num. Absorption spectrums. Valency se- lenide. Valency, chlo- roplatinate. Specific heat. K. Svensk Vet. Acad. Handl., 2, No. 8. Bull. soc. chim [2], 21, 246. Chem. News, 30, 21. J. Chem. Soc, 28, 34. Jsb. rein Chem., 1874, 77. Jsb., 1874, 257. Separat^n from [Bull. soc. chim. [2], 21, 196. Arch. ph. nat., 50, 212. Lond. R. Soc. Proc, 22, 241. Chem. News, 29, 148. Ber., 1874, 140. Jsb., 1874, 97- Ben, 1874, 31- Chem. News, 29, 155. J. Chem. Soc, 27, 430. Jsb., 1874, 118. Ann. der. Phys., Pogg., 156, 466. Chem. Centrbl., 1875, ^42- J. Chem. Soc, 30, 276. Jsb., 1875, 466. Am. J. Sci. [3], 12, 53. J. prakt. Chem. [2J, 12, 209. lanthanum. Dissociation of solutions. Heat of neu- tralization of oxyhydrate. • Metallic di- dymium. S75 Bunsen Ber., 1875, 129. Chem. News, 32, 176. Ann. der Phys., Pogg., 155, 633. ,S75 N^^^^" Nilson 5^6 iHillebrand Ann. der Phys., Pogg., 155, 378. Ztschr. anal. Chem., 15, 93. Am. J. Sci. [3], II, 142. Ber., 1875, 659- Ber., 1876, 1058, 1 145. Jsb., 1876, 292. Ann. der Phys., Pogg., 158, 75. 40 IHE QUARTERLY. Index to the Literature of Didymium — continued. Date. , Author. Remarks. References. 1 1 1876 Hillebrand . .Specific heat. • Phil. Mag. [5], 3, III. 1 1 ' 1 J. Chem. Soc, 3X, 50. Jsb. rein. Chem., 1876, 74. 1 Jsb., 1876, 74. 1876 Raramelst^urg. Atomic w'ght. Ber., 1876, 1580. | 1 1 Jsb., 1876, 240. 1876 Wyroboff. . . Ferrocyanide . Ann. chim. phys. [5], 8, 456. | Jsb., 1876, 312. 1876 Nilson . . . .'Platinonitrite. Ber., 1876, 1728. 1876 Pettersson . .'Molecular vol- Ber., 1876, 1566. t ume. 1877 Delafontaine . Occurrence in Arch. phy. nat., 59, 176. 1 N.Csamarsk'ie Jsb., 1877, 251. 1877 Cleve Compounds. Bull. soc. chim. [2], 29, 492. Ber., 1878, 910. 1 Jsb. rein. Chem., 1878, 80. 1878 Stolba Seprat'n from Bohm. Ges; d. VVissench., 1878. cerium and Jsb., 1878, 1059. lanthanum. 1 1 1878 Boisbaudran . Occurrence in |Compt. rend., 86, 1028. • rhabdophan. Ztschr. Kryst., 3, 191. 1 Jsb., 1878, 1228. 1878 Frerichs Researches. Ann. Chem.,Liebig, 191,331-366 and Smith. Ber., 1878, 804. Chem. Centrbl., 1878, 386. 1 1 Chem. News, 37, 250 ; 38, 59. i J. Chem. Soc, 34, 647. 1 Jsb. rein. Chem., 1878, 79. 1878 Frerichs . . . Compounds. Ber., 1878, 1 15 1. J. Chem. Soc, 34, 934. Jsb. rein. Chem., 1878, So. 1878 Delafontaine. Didymium in Compt. rend., 87, 632. N. C. samar- Chem. News, 38, 221?. skite. ijsb., 1878, 259. 1 1878 Delafontaine .; Probable com- Compt. rend., 87, 634. | \ pound nature ]Ber., 1879, 3^4. 1 of didymium Chem. Centrbl., 1878, 802. , from cerite. J. Chem. Soc, 36, 119. Monit. Sc. Quesneville 20, 1393. Jsb. rein Chem., 1878, 79. i Jsb., 1878, 259. 1878 Nilson . • . . Platnioiodo- Ber., 1878, 885. nitrate. 1878 Claes Absorption Ann. der Phys., Pogg. [2]. 3, 404. spectrum. 11^ To to t/. .ITER A TURE OF DID YMIUM. 4 1 ^teraturc of Didymium — continued. lOivoi. \ References. Literature. 87S x879 iSoret Wide occur- ,Gazz. chim. ital., 9, 11 8-1 40. rence of jj. Chem. Soc, 36, 696. didymium. jChem. News, 38, 164. !jsb. rein. Chem., 1878, 80. . I Absorption of Arch. ph. nat. [2], 63, 89. ultra-violet Compt. rend., 86, 1062. Boisbaudran and J. L. Smith 1879 1879 1879 Cleve Schuhardt Cossa . . 1879 1879 1S79 1879 1879 1880 rays. Absorption spectrum. . Compt. rend., 88, 323, 1167. ►Monit. Sc. Quesneville, 21, 450. Chem. Centrbl., 1879, 258, 483. ij. Chem. Soc, 36, 696, 861. Chem. News, 39, 286. Jsb., 1879, ^65- Ber., 1879, ^4^> 2080. Chloro-stan- Bull. soc. chim. [2], 31, 197. natedidymi'm J. Chem. Soc, 36, 602. a simple body. Jsb., 1879, 286. Metallic di- Chem. News, 40, 35. dymium. Occurrence in Compt. rend., 87, 377. scheelite, etc Ber., 1879, 3^2. Chem. Centrbl., 1879, 128. Jsb. Min., 1879, ^'5- Ztschr. Kryst., 3, 447. Chem. News, 40, 90. ,Jsb., 1879, 1179- Detection in Ztscher. Kryst., 3, 325. minerals. Jsb. rein. Chem.,. 1879, ^^• Soret \ Absorption ' spectrum. Compt. rend., 88, 422. Cossa Sella Fluorescence Ber., 1879, 1019, 2078. of salts. Chem. Centrbl., 1819, 308. Tungstate. Kopp . Stolba E. F. Smith R. Acad. Lincei., 3, 26. Ztschr. Kryst., 3, 631. Jsb. rein. Chem., 1879, ^^• Chem. News, 40, 90. Ber., 1879, 909- 1880 Marignac. Atomic weight Isomorphism, j Separation of Chem. Centrbl., 1879, 595 cerium and didymium. I Electrolytic Ber., 1880, 754. estimation. | Occurrence in Arch. ph. nat. [3], 3, 413. samarskite. Compt. rend., 90, 899. Ann. chim. phys. [5], 20, 535. Chem. Centrbl., 1880, 356. 42 THE QUARTERLY. Index to the Literature of Didymium — continued. Year. Author. Remarks. References. 1880 Marignac . . . Occurrence in Jsb. rein. Chem., 1880, 73. • samarskite. Jsb., 1880, 295. Occurrence in Ber., 1880, 1430, 1439. . 1S80 Nilson . . . . euxenite and Compt. rend., 91, 57. separation. Jsb., 1880, 300. 1880 Nilson and Moiecurrheat Ber., 1880, 14.S9. Pettersson. and volume. Compt. rend., 91, 232. \ Jsb., 1880, 237. 1880 Peroni and Occurrence in Gazz. chim. ital., 10, ^90. Schiaparelli. urine. Jsb., 1880, 11 14. | 1880 Cossa Occurrence in Gazz. Chim. ital., 10, 465. , urine. Ber., 1880, 2414. Jsb., 1880, 293. 1880 Cossa Tungstate. Gazz. chim. ital., 10, 467. Ber., 1881, 107. J. Chem. Soc, 40, 225. Jsb., 1880, 293. 1880 Soret Spectrum. Compt. rend., 91, 378. Chem. Centrbl., 1880, 662. Jsb., 1880, 210. Jsb. rein. Chem., 1880, 74. 1880 Soret Ultra violet !Arch. ph. nat. [3], 4, 261. absorption Jsb., 1880, 214. spectrum. 1881 Clarke . . . . Atom'c weight Am. Chem. J., 3, 263. Phil. Mag. [5], 12, loi. 'Jsb., 1 881, 7. 1881 Brauner. . . . Valency Pen- Chem. Ztg., 1881, 791. • toxide. ; 1881 Crookes . . . Phosphores- Lond. R. Soc. Proc, 32, 206. cence of Ann. chim. phys. [5], 23, 555. oxide. Compt. rend., 92, 1281. Chem. News, 43, 237. Jsb., 1881, 131. 1882 Brauner. . . . Researches. Sitzb. Akad., Wien [2], 84, 1165. 86, 168. Monatsh. Chem., 3, 1-60,486-503. Compt. rend., 94, 1718. Ann. der Phys., Pogg., Beibl., 6, 418. Ber., 1882, 109, 115, 2231. Chem. Centrbl., 1882, 616. Monit. Sc, Quesneville [3], 12, 595. 794. J. Chem. Soc, 41, 68. Chem. News, 46, 16. Jsb., 1882; 283, 285. TERATURE OF DIDYMIUM. 'terature of Didytnium — continued. 43 Remarks. 1883 1883 1883 1883 1883 Brauner . . A.tom'c weight Separation from cerium. Volumetric estimatiop. Separation from gallium. Preliminary note. References. Welsbach . . Arche . . . Stolba . . . Becquerel . . 1883 J- L. Smith. Atom'c weight Am. Chem. J., 4, 76. Chem. News, 45, 40. Chem. Centrbl., 1882, 151. Chem. Centrbl., 1882, 826. Jsb., 1882, 1286. Compt. rend., 94, 1439. Jsb., 1882, 1296. Compt. rend.. 94, 1528. Monit. Sc, Quesneville, 34, 689. Chem. Centrbl., i?82, 451. Ber., 1882, 1750. Chem. Ztg., 1882, 658. J. Chem. Soc, 44, 18. Chem. News, 45, 273. Compt. rend., 95, 33. Monit. Sc, Quesneville, 1882, 798. Chem. Centrbl., 1882, 616. J. Chem. Soc, 42, 1165. ,Chem. News, 46, 43. Atom'c weight Bull, soc chim. [2], 39, 289. 'Ber., 1883, 1 21 2. I J. Chem. Soc, 44, 852. Chem. News, 47, 203. Jsb., 1883, 37. Compt. rend., 97, 94. Ber., 1883, 2494. J. Chem. Soc, 43, 362. jChem. News, 48, 39, 74. Ijsb., 1883, 361. Separation fm Monatsh. Chem , 4, 630-642. other gado- linite earths. Preparation |Monatsh. Chem., 4, 913-925. from cerite. J. Chem. Soc, 46, 557. Estimation as Chem. Centrbl., 1883, 313. oxalate. I Absorption Compt. rend., 96, 1217. and emission Jsb., 1883, 243. spectrum. Preparation J. Chem. Soc, 43, 278-289, from cerite. Monit. Sc. Quesneville [3], 12, 595-625 ; 13, 160. Ber., 1883, i860. Jsb., 1883, 354. Occurrence in Am. Chem. J., 5, 80, samarskite. Chem. News, 48. 13, 29. Estimation by J. Chem. Soc, 46, in. Separation from samarium. spectroscope. Ber., 1883, 1886. Jsb., 1883, 1562. 44 THE QUARTERLY. Index to the Literature of Didymium — continued. Date. Author. Remarks. References. 1883 Debray . . . . Separation Compt. rend., 96, 828. from cerium. Chem. News, 47, 199. [893. 188-3 Thalen . . . . Spectrum. Ann. der Phys,, Pogg., Beibl., 7, Oefvers. konigl.Vet. Forhandl., v. 7. Ber., 1883, 2760. 1884 Haushofer , . Microscopic Ber. bair. akad. Wissensch., 13, test. 436-448. Jsb., 1884, 155 ^f- 1884 Robinson. . . Separation Lond. R. Soc. Proc, 37, 150. from cerium Chem. News, 50, 251. and 'Jsb., 1884, 50. lanthanum. | 1884 Welsbach . . . Separation Sitzb. Akad., Wien. [2], 90, 337. from cerium, 'Monatsh. Chem., 5, 508-522. lanthanum IJsb., 1884, 3^5. and yttrium. 1884 iCossa Molybdate. Compt. rend., 98, 990. Valency. J. prakt. Chem. [2], 29, 383. Ber., 1884, 249. Chem. Centrbl., 1884, 452. I'J. Chem. Soc, 46, 821. Jsb., 1884, 395- 1884 Cossa Diffusion of Gazz. chim. ital., 13, 280. didymium. J. Chem. Soc, 46, 262. 1884 Clarke . . . . Atom'c weight Chem. News, 50, 21. Chem. Ztg., 1884 1038. 1884 Hogbom . . . Tungstate. Bull. soc. chim. [2], 42, 3. Arch. phy. nat. [3 J, 10, 5, 193. 1884 Marignac . . . Equivalent . weight. Ztschr. anal. Chem., 23, 140. Chem. News, 50, 69. 1385 J. L. Smith . . Estimat'n sep- Chem. News, 51, 289, 304. aration from Ber., 1885, 515. other earths. Jsb., 1885, 1932. 1885 Linnemann. . Abs'pt'n lines Monatsh. Chem., 6, 533. | of didy'm in some zircons. 1885 1 Welsbach . . . Decomposit'n Monatsh. Chem., 6, 477-491. into constitu- Chem. Centrbl., 1885, 774. ents. Ber., 1885, ^^S- Researches. Chem. Ztg., 1885, 997. J. Chem. Soc, 48, 11 13. Chem. News, 52, 49. Jsb., 1885, 478. 1885 Cleve 1 Oxides. Bull, soc chim. [2], 43, 56. 1885 Hood 1 Absorption spectrum. Chem. News, 52, 271. 1885 Cleve Researches. Bull, soc chim. [2], 43, 3£;9-366. INDEX TO LITERATURE OF DIDYMIUM. 45 Index to the Literature of Didymium — continued. Date. Aulhor. Remarks. References. 1885 Cleve 1885 Lomi^ell 1885 Piccini . 1886 .Strohecker 18S6 Crookes . 1886 Demarcay spectrum, Spectrum. 1886 Morton . 1886 Humpidge 1886 Hartley. . 1886 Cossa . . . Crystalline I form of compounds. Spectrum. Spectrum. Tungstate and ' molybdate. 1886 tPlaats 1887 Bailey . . 1887 Becquerel 1887 Demarcay I . Researches. Chem. News, 52, 227, 255, 264, I 278, 291. Ber., 1885. 52, 318. J. Chem. Soc, 48, 1039. (Chern. Centrbl., 1886, 69. . Fluorescence. Ann. der Phys., Pogg. [2], 24,288. J Jsb., 1885. 333. . Position in ,Atti d. Ace. d. Lincei, 1885, 82. ' periodic Ber., 1885, 255. ! system. Jsb., 1885, 359. . Occurrence in J. prakt. Chem. [2], 33, 133. clays of Chem. News, 53, 136. I Hainstadt. Jsb., 1886, 407. Absorption Lond. Roy. Soc. Proc, 40, 502. Chem. News, 54, 27. Ber., i>86, 652. Jsb., 1886, 308. Compt. rend., 102, 155 1. Ber., 19, 650. J. Chem. Soc, 50, 837. Chem. News, 54, 36. Jsb., 1886,311. [1885, 189-199. Oefers. konigl. Vet. Forhandl., Ztschr. Kryst., 12, 517. Ber., 1886, 388. Jsb., 1886, 402. Chem. News, 53, 154. Chem. News, 53, 1 79. Atti d. Ace. d. Lincei, 1886, 320. Gazz. chim. ital., 16, 284. Compt. rend., 102, 1315. Ber., 1886, 482, 536. J. Chem. Soc, 50, 981. Chem. Centrbl., 1887, 1371. Ztscher. Kryst., 13, 299. Atom'c weight! Ann. chim. phys. |6], 7, 501. IZtschr. anal. Chem., 26, 276. . Atom'c weight J. Chem. Soc, 51, 682. Jsb., 1887, 53. Compt. rend., 104, 168, 777,1691. Ber., 1887, 246, 457. Chem. News, 55, 148; 56, 23. J. Chem. Soc, 52, 537, 873. Jsb., 1887, 352. Compt. rend., 105, 276. Ber., 1887, 533. J. Chem. Soc, 52, 1008. Absorption spectrum. Absorption spectrum. 46 THE QUARTERLY. Index to the Literature of Didymium — continued. Date. 1887 1887 1887 1887 1887 1887 1887 Author. Remarks. References. 1888 1888 1889 1889 1891 1891 1891 1891 1881 1892 Demarcay . . Absorption Chem. News, 56, 114, ^ spectrum. Jsb., 1887. 353. Kruss and Didymium Ber., 1S87, 2134. Nilson . composed of Chem. News, 56, 166. nine elements. Jsb., 1887, 474. Bailey ' Absorption Ber., 1887, 2769. i spectrum. Jsb., 1887, 474, Kruss and Occurrence in Ber., 1887, 1679. Nilson .! fergusonite. Jsb., 1887, 574. Willgerodt . .'Application as J. prakt. Cliem. [2], 35, 395. a chloridizing Jsb., 1887, ^i^* agent. C. M. Thomp- Absorption Chem. News, 55, 277. son. spectrum of comix)nents. Ouvard .... Phosphate . . Compt. rend., 107, 39. . Bull. soc. chim. [3], 51, 42. Chem. Centrbl., 1888, 1078. J. Chem. Soc, 54, 1037. Kiesewette Spectrum. Ber., 1888, 2310, 2320. I and Kruss Application. Eng. Mining J., 46, i. Absorption Chem. News, 60, 27. spectrum of J. Chem. Soc, 55, 259. components. ; Bettendorff . . SepV'tion fr'm Ann. Chem., Liebig, 256, 163. lanthanum. 1 Preparation Ann. Chem., Liebig, 263, 164. ' from orthite. j Kruss Separation Ann. Chem., Liebig, 265, 1-27. ' from erbium. Ber., 1891, 700. I J. Chem. Soc, 60, 1425. . Molecular re- J. Chem. Soc, 59, 595. fraction of salts. Ztschr. anal. Chem., 30, 144. Crookes Bettendorff. 1 89 1 Gladstone Behrens. . Hartinger. C. M. Thomp- ; son. .| Microscopic reactions. Absorption and emission spectrum. Didymium from different sources. Schottlander . Separation from lantha- nium and ce- rium ;spectr'm Monatsh. Chem., 12, 362-367. Chem. News, 64, 167. Chem. Centrbl., 189 1, 792. Ber., 1891, 945. Ber., 1892, 378-394, 569-599. Chem. News, 65, 205, 219, 233, 243» 254. Chem. Centrbl., 1892, 661. AN ORE-BUCKET FOR INCLINED SHAFTS. 47 Index to the Literature of Didymium — concluded. 1 Date. Author. 1 Remarks. References. 1893 Kruss Electrolysis of Ztschr. anorg. Chem., 3, 60. solutions. iChem. Centrbl., 1893, 3^2. iChem. News, 67, 65. Ber., 1893, 249. 1893 Kruss . . . . . Equivalent. Ztschr. anorg. Chem., 3, 58. 1 Chem. News, 67, 32, 40. 1 Ber., i«93, 249. 1893 Kruss and Behavior i Ztschr. anorg. Chem., 3, 92. Loose. toward Chem. News, 67, 75, 87, 100. potassium Chem. Centrbl., 1893, 4^^. 1 chromate. Ber., 1893, 250. 1893 Kruss Behavior Ztschr. anorg. Chem, 3, 108. toward Chem. Centrbl., 1893, 462. aniline. Ber., 1893, 251. 1893 Nordenskiold. Unknown na- J. prakt. Chem., 47, 20. 1 ture of Chem. Centrbl., 1893, 339. cerite. 1893 Eakins . . . . Didymium Bull. U. S. Geol. Survey, No. 64. | in Texas Chem. News, 67, 79. • gadolinite. AN ORE-BUCKET FOR INCLINED SHAFTS. By ALEXANDER L. BLACK. The buckets ordinarily used for hoisting gre and rock through inclined shafts using skids for a bucket- way are not at all suited to the work. There are many styles of buckets in use, but nearly all agree in having the body of the bucket curved in the vertical plane as well as the horizontal, that is, an " element " of the surface of the bucket is a curved line. When such a bucket is in contact with the skids, only a very small part of the bucket touches them. Under similar conditions the wearing part varies its position very little. So the hoisting of the loaded bucket wears it away in only a narrow zone.. A simi- lar zone is worn away by the lowering of the empty bucket. This brings practically all of the wear on two small zones, which soon wear through, rendering the bucket useless, although nearly all of it is in good condition. .1 48 THE QUARTERLY. The accompanying sketch shows a bucket designed to avoid this trouble. As will be noticed, the form is cylindrical, with the ends turned in somewhat to avoid cutting away the skids with the edge of the bucket. When either hoisting or lowering, it bears on the skids throughout a large part of its length, thus distributing the Oefoii cX ejt for ba'iL Ji* 3.^-1 S-«*^l- A so riveT*. f^ Oil riwcU 4' A countcr&unk on oul9id« Ore-Bucket to be used on Skids. Scale j\. wear over quite a large area. The ends of the cylindrical part of the bucket wear somewhat more than the middle, but on the whole the wear is evenly distributed over the cylindrical portion. [The greater wear on the ends is due to vertical curves in the shaft and to the inclined pull of the rope]. Buckets of this form have proven far more satisfactory than the old styles after quite a long test. AN ORE' BUCKET FOR INCLINED SHAFTS. 49 As to the details, the thickness of the plate forming the body is J<^-inch instead of y\-inch, which is more usual. This increased thickness almost doubles the life of the bucket without increasing much its weight. The greater stiffness of the heavier plate is suf- citnt to preserve the shape of the bucket without the stiffening- strap generally used about the mouth. Omitting this strap not only lessens the weight but is otherwise advantageous, for if the strap is on the outside, it cuts the skids; if on the inside, it pre- vents the clean discharge of the contents of the bucket. A single sheet of metal should be used for the body. The joint should come midway between the eyes for the bail, as in this position it is least apt to cause the bucket to lose its roundness. To secure greater smoothness on the sliding-surface of the bucket the joint should be a " butt-joint " with the joining-plate on the inside. The bottom of the bucket should be made of 3.^ -inch metal, as it must stand the blow of the falling material in filling. It should be dished to such an extent that the bucket can rest squarely on the ground without the dumping-ring touching. The dumping- ring is best fastened as shown (by a bolt passing through a large washer and nut with the end headed). This allows the ring to turn as a swivel, which is a great convenience in dumping. For greater ease in attaching the dumping-hook it is well to put a large h'nk in the ring as shown. The rivets should all be countersunk on the outside to avoid projections, which loosen the rivets and cut the skids unneces- sarily. The bail should have the ends bent out as shown. The wear of the bail comes on the outside just above the eye. If the end is bent in. the wear weakens the part of the bail which supports the load. If bent out, the wear does not affect the strength of the bail. The material of which the bucket is made should, of course, be the best. A mild steel wears better than iron, is stronger, and does not much increase the cost, so is to be preferred. The life of the bucket can be increased by protecting it with straps on the outside. But these straps tnuch increase the wear of the skids, so their use is not recommended. VOL. XV.— 4 50 THE QUARTERLY. AN ASSAY FURNACE BURNING WOOD. By ALEX. L. BLACK. Recently, in one of the mining-camps of Colorado, I met with a novehy in assay work, a notice of which may prove of interest and use to some of the readers of the Quarterly. The novelty . consisted in the use of wood as a fuel for assaying. As is usual in Colorado, all of the work is done in a muffle. The furnace is shown in the accompanying diagrams. It acts as a reverberatory and has only a very narrow space between the muffle and walls. The grate is of the style generally used in stoves — in fact, was made for that purpose. The area of the grate is quite small in comparison with the size of the furnace, but the space for fuel is quite large. The heat produced is entirely satisfactory, there being no diffi- culty in keeping silver in a molten condition in the muffle. The wood is cut to the usual stove size, and is carried on the grate to a depth of 5 or 6 inches. The design shown is for a muffle 9 by 15 inches. As it was arranged for using the standard forms of brick and tile, some of the details are peculiar. The great objection to this form of furnace is that the firing must be done frequently on account of the rapidity with which the wood burns out. But in many places where other fuels are diffi- cult to obtain or very expensive, this form of furnace may prove advantageous. Any wood suitable for steaming purposes will prove satisfactory in this furnace. AN ASSAY FURNACE BURNING WOOD. 51 Lor«^<'uclinal ^actiofi. Cro ^S'SettiQn front Eltoettian. • c o E £ c O GO Scale y'y. ABSTRACTS. Analytical Chemistry, by E. Waller, Ph.D. Aluminum Apparatus. Bornemann. {Berichte, xxv., 3637). For apparatus which is not subjected to a heat above 400-500 C. especially when brought in contact with H^S, Al miy be advantageously used. For water-baths it is better than copper. Heating to a dark red heat is fatal, rendering the metal granular and brittle. Agitator for Precipitation of Phosphomo ybdate y etc, Textor (y". Anal, App. Chefn.y vii., 279), describes a device connected with a Richard's pump, for agitating by passing a current of air through the solution. Sodium Peroxide as a Reagent. Clark {J, Lond, Chem. Soc, Ixiii., 1079). Reference is made to Hempel's recommendation of this reagent {I'id. Quarterly xiv., 360.) The reaction on heating with coal, coke or even with such a substance as filter paper is so violently explosive that it cannot be used with them. If mixed with pyrites and only gently heated, dilution with soda is unneccessary. The reagent is especially good for decomposing chrome iron, or attacking ferrochrome. A water solution (which will not keep long) is serviceable for separation of Mn from Zn, Ni and Co in ammonia solution. In the case of the two last, resolution and reprecipitation are necessary. Ammonia in Zinc Dust. Robin eau and Roll in (Mo nit. Sci.^ vii., 138), find that zinc dust always contains ammonia, which cannot be removed by boiling with water. Complete removal is only attained by washing with boiling i per cent. H^SO^. Standardizing Alkalimetric Solutions. Neitzel (Fres. Zts.Anal. Chem., xxxii. 422), revives the proposition of Hartley — the use of metallic so- dium. The metal must be weighed under petroleum, and then oxidized by the use of strong alcohol. Volumetric Determination of Pyrophosphoric Acid, Favrel (Bull Soc. Chem. [3] ix„ 446). Na^H^PjO^ is neutral to cochineal, whereas with Porrier blue C4B neutrality is only shown by Na^P.^0,. On these facts a method for determination is based. (/^., p. 448) Favrel records that cochineal is indifferent to HjAsO,, and the base combined therewith may be accurately estimated by an alkaline solution, using cochineal as indicator. Boric Acid Titration, Thomson (J.S, C. /., xii., 432). On adding phenolphthalein to a solution of H^jBOj, and titrating with fifth normal NaOH, the end-reaction was indistinct, and valueless. Addition of glycerine developed the acidity of the acid, and when the solution con- tained 30 per cent, of glycerine the end-reaction was sharp when enough ABSTRACTS. 53 NaOH to form NaBO^ had been added. A further addition of glycer- ine caused no increase in acidity beyond this point. The method re- commended for determining HaBO, in borax etc., is essentially this : Dissolve in water, add methyl-orange, (on which H^BOg has no effect) and then render just acid with standard H^SO^. Boil out CO, etc., and just neutralize (to methyl-orange) with normal or fifth normal NaOH. Then all H3BO3 is present in the free state. Then add glycerine (:rO that at the end the solution shall contain at least 30 per cent.) and phenol- phthalein, titrate with normal or fractional normal NaOH. ICC. Normal NaOH s= 0.0620 gm. H3BO3 = 0.0505 ** Na,B,0^ = 0.0955 ** Na^B.O,. loH^O. If, as is sometimes the case, the borax etc., contains ammonium salts, boil with Na^COj before acidifying with H^SO^, etc. Potassium Determination. Villiers and Borg (^BulL Soc. Chem. [3] ix. 602). After obtaining K^PtCl,, well washed with a mixture of alco- hol and ether, dissolve through the filter with boiling water, acidify with HCl, insert strips of metallic Mg, boil until all Pt is reduced, and Mg dissolved, and filter and weigh Pt. Precipitation of K,PtClg, in presence of sulphate always gives low results. If bromides are present, the precipitate contains some Br in place of CI. Errors due to this fact are avoided by weighing the metallic Pt of the precipitate. Potassium by Lindo- Gladding Process, Holleman {Chem. Zeit.y xvi. 1920), finds the process trustworthy when properly conducted in opposition toBreyer and Schweitzer who condemn it. Those chemists reiterate their condemnation {Chem. Zeit.^ xvii., loi) making the point that the results by it are not concordant and are higher than the Stass- fort method. Separation of Baryta. Strontia and Lime. Fresenius {Zts, muii. Chem. xxxii.. 312). For qualitative purposes, dissolve the precipitated carbo- nates in dilute HNO3, evaporate to dryness and heat (the temperature may reach 180° C. without disadvantage) until no acid odor is percept- able and moisture is expelled. Cool, pulverize, and extract with 5 to 10 c.c. of a mixture of eqpal volumes of absolute alcohol and ether, finally washing on the filter with this solvent. Ca(N03)j, and (perhaps) traces of Sr(N03\ are dissolved. A copious and immediate precipitate in the solution on adding a drop of H^SO^ indicates Ca. A faint cloud may be due to traces of Sr, or of Ca. Add 4 c.c. H^Oi evaporate off the alcohol and ether, then add a few drops of ammonia and about i gm. (NHJj SO^, boil, filter, acidify with a drop of HC^HjO,, and then add a littiC (NHJjCjO^. A precipitate indicates Ca. The nitfrates insolu- ble in the other-alcohol, are dissolved in about 100 c.c. of water, fil- tered if necessary, acidified with HC^HjO^, heated to boiling and K^Cr- 0^ gradually added until an excess is present. BaCrO^ is precipitated. Allow to stand some hours. Test a little of the clear supernatant fluid or filtrate with ammonia and (NHJ^COg a decided precipitate indicates Sr. If the precipitate is none or but slight, add a few drops of HNO^, 54 THE QUARTERLY. concentrate to lo or 20 c.c. and test with- (NHJjCO, as. before. A small precipitate may be due to traces of Ca. Filter off, dissolve in a little HCl, evaporate to dryness, and dissolve the residual neutral chlo- rides in I to 2 c.c. of a mixture of 3 parts Hj,0 and i part alcohol, add a few drops of KjCrO^ and heat to incipient boiling. Under these conditions SrCrO^. will precipitate. For quantitative separations the following points must be noted: i. For the exact separation of BaO from SrO and CaO, only two methods are suitable, namely, separation of BaO aschromate or silico-fluoride. 2. The separation of SrO from CaO, succeeds satisfactorily only by treating the nitrates with ether-alcohol. This treatment is also adapted for the separation of BaO from CaO. 3. A solution which contains H^SiF,, besides CaO and SrO, is poorly adapted for the determination of both alkaline earths, since these can only be precipitated out as sulphates, a form in which they cannot be directly separated. Plans of procedure are sketched as follows : a. Separate Ca by the action of ether-alcohol on the nitrates, and then separate Ba as BaCrO^. (Essentially the plan given for qualitative work). b. First separate Ba as chromate, then convert Srand Ca into nitrates and separate by ether-alcohol. Test analyses show that Sr tends to run a little high, the others low. Iron and Aluminum in Bone Black. Wiechmann {Science ^ xxi., 300), has investigated the ammonium acetate method, that of Glaser, and a combination of Glaser and Stutzer's methods. The combination method was found to be the most satisfactory. This consists essentially in carrying out the Glaser method to the point of obtaining the precipi- tate of iron and alumina phosphates {jnd. Quarterly, xi., p. 273. Then instead of igniting and weighing, treat the precipitate with molybdate solution, at 65° for 12 hours or more, filter off the *' yellow precipitate ** wash with NH^NO,, and in the filtrate, precipitate Fe^O, and Al^Oj with ammonia, warming gently for two or three hours. Filter, redis- solve the precipitate in HCl, and precipitate by ammonia for weighing. The errors incident to calculating Fe,Oj and A1,0, on the assumption that the precipitate in the Glaser process consists of FePO^ + AlPO^, are pointed out. Aluminum in Ferro-aluminum. H.V. Juptner {Oest. Zis, Berg, u. Huti,, xli., no), describes his method, which is practically the old one — precipitating and weighing Fe^O,, Al^Oj and P^Oj together, and in aliquot parts determining Fe. and PjO^ estimating Al by difference. Neuhausen's method consists in dissolving 5 gms. in dilute H^SO^, evaporating to dryness, taking up with dilute HjSO^ diluting to 300 c.c. reducing with iron wire, neutralizing with Na^CO, and pouring into a mixed boiling solution of KOH and KCy. After filtenng, the solution containing the Al is heated for an hour with addition of NH^NO,, and the Al/OH)g filtered off. This precipitate must be tested for KOH and for Fe. Chromium Determination. Jannasch and Mai {Berichte^\\w\y^ 1786). One gm. K^Cr^O^ was reduced by use of HCl and alcohol, and after ABSTRACTS. 55 evaporatinpr off the alcohol, dihited to 300 c.c, boiledyand 2 gms. pure hydroxy] am in chloride added, thereupon to the solution removed from the heat a moderate excess of ammonia. The Cr.,(OH), was completely precipitated, free from alkali, SiO^, etc., and in the clear filtrate K was determinable by evaporation to KCl. Manganese in Iron, Schneider, (Oester. Zts. B, u. Hiiifwesen^ xxxiv., 308) dissolves in HNO3 (Sp.Gr, 1.2) converts to H^Mn^O^ by addition of Bi,0^, and titrates with H.^O^. Manganese Deiermi nation. Carnot {Compt, Rend, cxvi., 1375). Ig- nition of Mn oxides when absolutely pure yields Mn^O, but the presence of even minute amounts of other substances alters the result. Evapora- tion of an Mn solution in HNO3 does not afford all of the Mn as MnO^ unless it is repeated two or three times. The KCIO., precipitation in strong HNO3 requires repetition also in order to obtain pure MnO,. The most ready method for obtaining a higher Mn oxide of constant composition, consists in adding H.^O.^ to the Mn solution, then ammo- ria in excess and boiling. The precipitate is Mn^O„. By determining the ''available oxygen" in this precipitate (see below) the Mn may be determined. Resolution, and reprecipitation of the Mn^O,, is necessary if Cu, Zn, Ni or Co are present. Co requires ?iwt precipitations, the others but three. MnC^, if precipitated by Br in ammonia solution, re- qjires prolonged washing. Manganese Permanganates. Gorgen {Bull. Soc. Chem. [3] ix., 490), contests the assertion of Guyard that three permanganates may be ob- tained, viz., Mn^Op 5 MnO (= Mn^O,.^), Mn^jO, 4 MnO (= MngO,,) and Mn^O,, 3 MnO ( = Mn^Oj^, = 5 MnO^). The experiments re- corded indicate that those oxides are not permanganates. Nickel Estimation, Syssoyeff ( J/<?« Sci. [4] vi., 865). To the dilute solution, KCy is added in sufficieni quantity to form the soluble double cyanide. NaOH is then added, and CI passed in to obtain NijO, or the corresponding hydrate. The precipitate,^ collected on an asbestos filter, is treated with H,0, in a modified Lunge gas volumeter and the evolved oxygen measured, the reaction being Nip, + H,0, = 2 Ni -f H.p + O,. Copper Titration. BorntrsigeT (Zts. A ngew. Chem., 1893, 517) de- scribes his mode of applying Pelouze's method. (Titration in ammonia solution with Na.^S.) To avoid any separation of oxysulphide, the titra- tion should be performed in the cold, with vigorous agitation. For the end-reaction the use of alkaline Pb solution is better than the nitro- prusside test ; but the author prefers to either, the filtration of a few drops of the solution into solution of ferrocyanide, strongly acidified with acetic acid. When all Cu is precipitated, the reddish Cu.,FeCy5 does not appear. For standardizing, use Cu solution, containing the equivalent of 10 gms. of metal per litre. The Na^S solution should equal this, c.c. for c.c. It should be made by dis^^olving 40 gms. of commercial Na,S in one litre. The solution should be kept in small S6 THE QUARTERLY. well-filled bottles, and standardized whenever it is used. The strength was found to be reduced about one half by keeping for i8 months. In presence of Zn, CuS will form first, so that the titration can be con- ducted in a solution of brass, etc. The application in the cases of some other commercial products is described. Colorimetric for Mercury. Vignon {^BulL Soc. Chim, [3] ix., 504) finds that a colorimetric method may be used for small amuunts, de- pending upon the intensity of color imparted by addition of excess of HjS water. Separation of Lead and Tin. Jannasch and Remmler (^Berichte^ xxvi., 1422). The metals were precipitated together as sulphides, which, after washing and drying, were heated in a current of Br. SnBr^ was readily volatized off, by repeated evaporation with HNO, converted to oxide, and then ignited and weighed. Converting the metals into sul- phides by fusion with S was successful as a mode of shortening the man- ipulation in many cases. Some difficulty was experienced in completely sulphurizing metallic tin if in coarse pieces. The addition of 10 to 15 per cent, of iodine with the S, gave excellent results in sulphurizing either tin or antimony. Separating Lead and Silver, Jannasch {Berickte, xxvi., 1496.) Dis- solve about 0.5 grm. of the mixed salts in 50 c.c. of water; add 2 c.c. strong HNO„ and then precipitate PbO, by adding 15 to 20 c.c. of 2 per cent. H^O^ solution with 15 c.c. cone, ammonia, afterward adding 5 c.c. of a cold saturated solution of (NHJ^COj. Stir 10 minutes, filter, washing at first with ammoniacal water, finally with clear water. The operations must be conducted in the cold. Convert the PbO, to sul- phate and weigh. In the ammoniacal filtrate the silver can be deter- mined by evaporating off the excess of ammonia, acidifying with HNO,, and then precipitating with HCl. Bi can be separated from Ag in a similar manner. Ag may also be separated from Pb by precipitating both as chromates, adding ammonia and digesting a short time on *the water-bath. Ag^CrO^ is completely dissolved, leaving PbCrO^. Filter, and wash first with dilute ammonia, finally with water only. Analysis of Tin- Ores. Moore {Chem. News, Ixvii., 267) reports an investigation of some of the methods recommended. Boiling the ore with aqua regia removes no Sn. Fusion with Na^S^Oj, affords complete decomj)osition if the fusion is kept up for fully one hour, but not in less time. The precipitate of SnS^ is, however, troublesome to handle. Hal- leti's fluoride method proved unsatisfactory. KCy methods were not tried. The zinc-reduction method (Wells, Quarterly, xii., 295) was not satisfactory as described, the precipitated metal enclosing particles of ore. An improvement is recommended, as follows: charge a porce- lain crucible with a layer of Zn powder free from Pb at the bottom ; on this 0.5 gm. of the ore, mixed with 5 or 6 gms. Zn pvowder ; then a thin layer of Zn powder, and on top of this a solid well-burned piece of charcoal. Put on the cover and place in a hot muffli until almost all Zn fume ceases; cool without removing the lid, take out the charcoal, ABSTRACTS, 57 and dissolve Zn and Sn in HCl in an atmosphere of CO,. Add to the hot solution a known amount of Fe,Clj solution, cool, filter rapidly, and titrate excess of FejCl, with Cu.^Cl, solution, using KCyS as indicator (Winkler's process reversed). The process is unaffected by the presence of much ZnCl,. In solutions containing the tin as SnCl^, this process may also l)e applied after reducing by Pb. Concentrate the solution to small bulk, add one fourth its bulk of strong HCl, then 5 or 6 gms. test lead, and heat gently for 2 hours on a water-bath, or boil 15 minutes. Pour in excess of FeCI^ solution, and titrate with Cu,Cl, as before. Titration of Arsenic and Antimony. Gyory i^Fres. Zts. Anal. Chem,, xxxii., 415) notes that the end-reaction with I solution (in presence of NaHCO,) especially in the case of Sb (the As or Sb being of course triad) is slow. He proposes using a solution acidified with HCl, and containing KBr, adding a little methyl orange, and then titrating with standard KBrOj. The end-reaction is when the solution becomes col- orless. M Cerium Reaction. Plugge {^Arch. d^ Pharm.^ ccxxix., 558) reverses Sonnenschein's test for strychnia, and uses strychnia sulphate as a test for cerium. The solution suspected of containing Ce receives the ad- dition of dilute NaOH sufficient to give perceptible alkalinity. It is then evaporated to dryness, and a few drops added of cone. H.^SO^ in which one-thousandth part of strychnine has been dissolved, o.oi mgm. CeO gives a perceptible blue violet color, which is weak and soon dis- appears, o.i mgm. gave a strong reaction, first blue, then permanently red. The oxalate will not give this reaction until after heating, to de- stroy the oxalic radical. £iectrolytic Methods. Oettel {Chem. Ztg.^ xvii., 173) asserts that in the account of electrolytic methods a very important factor is usually omitted, viz. : the number of amperes psr unit of area of the electrode. The shape and disposition of the cathode have of course some influence, and should be noted. A statement of the strength of the current, in c.c. of gas given off, is less satisfactory than statement in amperes. Voltage is regarded as of less importance. Electrolytic S parations. Smith and Moyer (/. Anal. App. Chem., vii., 252). In HNOj solution Hg and Pb were separated perfectly when much HNO5 was present, imperfectly, when the free acid was less. When Bi was present with both the above metals in HNO3 solu- tion, no matter what the other conditions, Bi was deposited both on the cathode with the Hg and on the anode with the PbO,. Separations of Ag from Pb, Cu from Cd and from various metals of the (NHJ^S group, were easily accomplished in HNO, solution. Also Bi from Cd, or from metals of the (NH J,S group when only one was present. When two or more were present, a complete separation was difficult in HNO,. Electrolytic Separations, Sch mucker {J. Am. Chem. Soc, xv., 195). In ammoniacal tartrate solution containing tin as stannate, a perfect separation of Cu could be effected. Cu was also satisfactorily separated from a solution containing As, Sb, and Sn under the same conditions — 58 THE QUARTERLY, highest oxidation and presence of ammoniacal tartrate. Cd and Bi were separated from those elements under the same conditions provided the current was weak and sufficient time was allowed. Hg was also completely separable under the same conditions as Cu. Deiernnning Sulphocyanic . Cyanic and Hydrochloric Acids, Jumeau (^Butl, Soc, Cnim. [3], ix., 346). HCNS may be determined by titra- tion with standard permanganate in acid solution, which affords H^SO^ and HCy. HjSO^ if present may be determined by evaporating the solution first with HCl to decompose HCyS, and then precipitating with BaCl^. When HCNS together with either HCy or HCl is to be determined, the two acids may be determined together by titration with AgNOj and then in another portion HCNS by permanganate. If all three are present, precipitate by AgNOj, and weigh the combined silver salts. Dissolve in ammonia, and determine HCNS by permanganate, check- ing by precipitating the H.^SO^ formed by use of BaClj. In a weighed portion of the mixed silver salts determine N by Kjeldahl method, de- duct that due to HCNS, and reckon the rest to HCN. Get HCl by dif- ference. Phosphorus in Irons, Carnot {Bull, Soc. Chim. [3], ix., 340. Take 0.5 to 5 gms. according to the content in P. Add 40 c.c. HNO, and heat, when effervescence ceases, add 10 c.c. cone. H^SO^, evaporate gently, dry, heat to 120-125° C. for two hours, take up with 50 c.r. boiling water, filler and wash. The Si02 in the residue may be washed with HCl, dried and ignited if it is desired to determine it. To the so- lution containing ihe phosphorus add i gm. CrO, and heat for about thirty minutes. Then add 4 gms. (NHJ,^SO^ and then 50 c c. molyb- date solution, and heat to 100® for about an hour. Wash by decanta- tion with lukewarm water containing one-twentieth its volume of molybdate solution. Dissolve the precipitate in 30 c.c. ammonia di- luted with an equal volume of water. Wash with 50 c.c. boiling water. Cool the solution, neutralize with HNO,. When the precipitate begins to be permanent, add 3 c.c. HNO3. Keep at 40° C. for two hours, filter through a weighed filter, wash with 1 per cent. H NO,, solution, dry at too° C. and weigh phospho-molybdate (containing 1.628 per cent. P.) Arsenic acid requires a temperature of 60° C. or over to precipitate as the molybdate. The composition of the precipitate as found by the author, and as given by others may be seen from the fol- lowing table : 1868 H. Debray Rammelsberg Finkenep [i'^7^ W. Gibbs Carnot P.,03 20 MoO, 3(NHJ, 0.3H,0 (P^ = 1.918). 1877], PA 22 MoO, 3(NHJ, 0.i2H,0 (P,= 1.684). " "' P.p, 24 MoO, 8(NHJ, O.H.,0 (P,= 1.656). P,03 24 M0O3 5(NH J, O. i6H,0 (P, = 1.597). [1893], PA 24 MoO, 3(NH,), 0.3H,0 (P, = 1.628). Phosphorus in Soils, Carnot (^Bull. Soc. Chim, [3], ix., 343). The nature of the organic matter likely to be present, and the possible pres- ence of CaSO^, render some modifications necessary, as compared with the method given for P in irons. Ten gms. of the dried and sifted ABSTRACTS, 59 earth is first roasted at a moderate heat. HNO3 ^^ ^'"^^^ added cautiously until effervescence ceases, then 10 c.c. more of HNO3 is added, and after digestin^T for two hours on a water-bath, the solution is filtered. It is then concentrated to 50 c.c. Five c.c. cone. HNO, is added, and about 0.5 CrOj and it is digested on a water-bath, a return condenser being attached. Then add 5 gms. NH^NO, and 50 c.c. molybdate solution, and continue as described for P in irons (second precipitation and weighing the molybdate precipitate). Phosphoric Acid in Basic Slags, Foerster {Chcm. Zcif., xvi., 1596), states that no method is trustworthy. The best results are obtainable by boiling with dilute suljjhuric acid, and precipitating by molybdate. Determining Phosphoric Acid, Villiers and Borg {Compf. Pend.y cxvi., 9S9). The reagent consists of 150 gms. (NH^)^ MoO^ dissolved in one litre of water, aifding subsequently one litre of HNO, (gr. 1.2). 100 c.c. should be used for every o.i gm. P^Oj present. Run the reagent in without mixing, and do not stir until two hours have elapsed. Pre- cipitation will be complete on standing at 15° C. for four hours, unless retarded by the presence of salts; in that case four hours at 40 C. gives complete precipitation. Longer gives MoO, as a contaminant to the precipitate. VVash with water containing 5 per cent, of the molybdate solution by volume. One gm. of the precipitate (dried at not over 100°) contains 0.03728 P^Oj. In presence of Fe or Al the precipitate always contains their oxides. In that case, dissolve in ammonia, add tartaric acid and precipitate with magnesium mixture. Colorimetric Determination of Phosphorus. Osmond {Bull. Soc. Chim., xlvii., 745) uses a solution containing 12 gms. cryst. SnCl, and 80 c.c. cone. HCl per litre. The phospho-molybdate precipitate after separation and washing on an asbestos filter, is dissolved by passing through the filter 100 c.c. ot the SnCl, solution (to the grm. of manu- factured iron taken for analysis.) The reddish-yellow coloration is com- pared, as regards intensity with standard solutions containing known amounts of -phospho-molybdate. Determining Sulphide Sulphur, Marchlewski {Fres. Zts. Anal. Chem., xxxii., 403). Continuation of Examination of Methods {vide Quarterly, xiv., 163). Groger-Treadweirs method consists in heating pyrites, etc., with metallic iron to obtain monosulphide, then treating with HCl, and passing the evolved H^S into iodine solution, and titrating back the ex- cess of I. The method is unsuitable for the examination of pyrites, since a part of the sulphates (frequently present) are also estimated by this process. The S in PbSO^ was only partly obtamed by application of this process. Sauer's Method. — Combustion in a stream of O, passing the gases into a KOH solution of Br, heating and precipitating by BaClj, is rather elaborate and tedious. Fohr's Method. — Passing the evolved H^S into arnmoniacal zinc solu- tion, adding Fe^vSOJ,, and titrating with permanganate, gave irregular results. Klobukow's method, presumed to be applicable for the determina- tion of S in the higher sulphides, and also in sulphites, hyposulphites. 6o THE QUARTERLY. m etc., proved unsatisfactory. It consists in mixing the substance with zinc dust, adding acid, and heating, when the S is presumably all con- verted to HjS, which is caught and determined iodometrically. Barium Sulphate, Browning {Am,/. Sci., xlv., 399). Experiments are quoted which go to show that the presence of 10 to 15 per cent, of strong HNO.„ by volume in a solution, does not materially diminish the amount of BaSO^ precipitated. Aqua regia had still less solvent power. In presence of salts which exert, ordinarily, a solvent action, citrates, metaphosphates, etc., the addition of 10 per cent, of HNO3 renders the precipitation complete, but the precipitate needs subsequent purifica- tion. Evolution Method for Sulphur, Crobaugh {/, Anal, App, Chem,^ vii., 280). Experiments with ammoniacal solution of CdClj indicated that the ammonia itself tends to hold the H^S, though somewhat unevenly. Passing the gas through two inches of ammoniacal CdCl, solution, con- taining about 0.04 to 0.06 gramme CdClj, would suffice for all the sul- phur in 5 grammes of Bessemer iron. Silicon in Irons, Ford (y. Anal App, Chem,^y\\,y 277) does not find that, allowing the H^SO^ solution (Drown*s method) to stand for some time causes error, as mentioned by Dudley (Quarterly, xiv., 261). His method of management is to dissolve in dilute H^SO^ (i : 5), after com- yjlete solution, to add HNOj, until effervescence ceases, and then to evap- orate. Before dissolving in hot water a few drops of HCl are added. Boric Acid, {Compt. Rend,^ Abs. in Chem, News, Ixvii., 309.) A modification of Gooch's method is recommended. Free the Bo^O, by heating with HNO3 in a sealed tube, transfer to a flask, distil off with methylic alcohol, condensing in Bohemian glass. Absorb the vapors in ammonia. After distillation, unite the distillate in the Bohemian glass vessel with the ammonia solution, pour upon a lot of previously-weighed CaO, let stand 15 minutes, evaporate at 70°, heat up gradually, calcine and weigh. For 0.5 gramme B^O^ use 8 to 10 grammesCaO. The CaO must be very carefully prepared for the purpose. Carbon in Iron and SUel. Petterson and Smett (Jernkontorets Ann, pery. Am, Chem, Soc, xv., 213), describe an apparatus in which the oxidation is effected by fusing KHSO^ (35 grammes for 0.5 grammes of iron). Tl^ resulting gases are passed through QxO^ crystals to remove SO.^, and then into Ba(OH).^ which absorbs the CO.^. A current of air (free from CO,) is passed through the apparatus during and after the operation. Carbon in Steel. Lorenz {Zts, angew Chem,, 1893, 313, 395, 411) proposes, as the most accurate, weighing 2 to 6 grammes of drillings in a porcelain boat, covering this with a layer of PbCrO^, and then submit- ting to combustion, at white heat, in a current of air. The method by volatilization of Fe in a current of CI, if pressed too far, causes a loss of C; if not far enough, some carbides are retained which afterward escap;i oxidation. The method by solution of the Fe in CuSO^ gave ABSTRACTS. 6i lower results than with the douhle chloride (2NH^Cl,CuCl2). With the latter, several days are necessary for complete decomposition. The amount of carbon obtainable slowly increases up to a maximum, and then diminishes. The error introduced by use of the ammonium com- pound, as pointed out by the American Committee, seems to be ignored entirely. Nitrogen in Nitrates, Schmitt {Chem. Zeit., xvii., 173). Dissolve 10 gms. of the sample and dilute to 500 c.c. Place in a flask (round bottom) of about 750 c.c. capacity, 10 gms. of an equal mixture of iron and zinc powder, add 10 c.c. glacial acetic acid and then run in slowly 25 c.c. of the solution of the sample (=0.5 gm ). After ten minutes when no more gas is evolved, add 200 c.c. of water, and 30 c.c. NaOH solution (gr. 1.25) and distil ammonia as usual. Defer9nination of Nitrates, Gruener (^Am. ^our, Sa., xlvi., July, 1893). The nitrate, not to exceed in amount 0.05 gm., KNO,, is in- troduced into a retort, together with ten times its weight of KI and 17 to 20 c.c. of phosphoric acid (gr. 1.43). All water used should be recently boiled. CO.^ is passed through. The neck of the retort passes into a receiver containing: a known amount of tenth normal As^O,. alkaline with excess of NaHCO,, and diluted. A safety trap is attached containing water. The solution in the retort is boiled until it is clear that no more iodine remains, when the receiver, after proper washing, and the addition of the water in the trap, is titrated with iodine to determine the amount of As.,0., left. The reaction with the nitrate is : '2^3 2HNO, + 6HI = 4H,0 + 2NO + 3I, Experiments on the decomposition of nitrates with SbCl, were successful when special conditions were maintained. Azwiable Oxygen in Manganese Mineral. Car not {Compt. Rend.y cxvii., I 295). In presence of an acid H.^02 reacts with all of the higher Mn oxides, affording twice as much oxygen as is "available'* in the samples eg.: MnO, + H^O,^ MnO + H,0 + O, MujO, + H,0,= 3MnO + H,0 + O,, etc. By treaMng the oxides (mineral or other) with acetic acid or with very dilute HjSO^ or HNO3 ^^ ^ suitably arranged apparatus, the evolved oxygen may be measured. If carbonates are present, a preliminary treatment with acid is required. Heat need not be applied. Determining Organic Matter. ITeidenhain (^Am, Chem, Soc, xv., 71 ), proposes a slight modification of Hehner's method— boiling with concentrated H^SO^ and K^CrjO,, and subsequently determining the residual CrO, by standard FeSO^ solution. The proportions used are 25 c.c. of the solution of the substance, 30 c.c, fifth normal K^Cr^O^, and ^^ c.c. cone. H,SO^. The operation is conducted in a large flask, in the neck of which is hung a U tube, through which water circulates, 62 THE QUARTERLY. to act as a reversed condenser. The method is not universally applicable. The degree of dilution specified, reduces the independent reaction between H^SO^ and K^Cr^O^ to a minimum. Analysis of Iron and Steel. Parry and Morgan have published a series of papers on this subject, which are reproduced in Chem. Ntws^yo\. Ixvii., as follows: Silicon, p. 149 ; phosphorus^ p. 161 ; carbon, p. 175 ; graphite, sulphur, p. 247; copper^ twtgsten, iron oxide, titanium^ p. 259; ffianganese, arsenic, p. 295 ; chromium^ aluminium, calcium^ magnesium^ etc., p. 307. The methods are rather older and more conservative than those in use in our metallurgical laboratories at present, some of the sug- gestions may be noted as illustrating; the practice in English metallurgical laboratories. Silicon. — The necessity for sampling carefully, especially in the case of gray iron is noted. Use 4 gms. and 50 c.c. aqua regia [i part HNO, (gr. 1.42) with 3 parts pure HCl], evaporate to dryness and heat over a Bunsen until black. Cool, take up with 60 c.c. HCl, evaporate to a crust, dissolve in dilute HCl, dilute with 5 volumes of water, and filter. Wash, first with 10 per cent. HCl, then with water. If graphite is present, burn off the filter paper at the lowest temperature possible, weigh SiO^and graphite together, and then burn off graphite and weigh SiO,. The residue even though white, may be impure. Fuse with KHSO^, pulverize, dissolve in cold water and filter off pure SiOj. As an alternate method one can dissolve 4 gms. in 60 c.c. H^SO^ (i '.3) evaporate to fumes, dilute and boil to dissolve FeSO^, filter and wash. Phosphorus. — The molybdate solution is made up thus : Dissolve 60 gms. (NHJ^MoO^ crystals in water, dilute to i litre, then add 50 c.c, ammonia (gr. 0.88) and slight excess (?) NH^NOg. Let stand two days and then decant clear. For ordinary work take 4 gms. of the sample, according to conditions i to 10 gms. may be desirable. Use 60 c.c, aqua regia. Evaporate as in the case of silicon, evaporating the second time to complete dryness. Redissolve in HCl, then evaporate repeat- edly with HNO3 (g^- 1-42) to remove HCl. Finally add enough HNO3 to make the solution flow freely, then 50 c.c. of the molybdate solu- tion. The solution must then be brought to a point where it is but slightly acid ; experiments are quoted to show that the precipitate is somewhat soluble in dilute HNO3. Filter, wash six times with 10 per cent, (by volume) HNO3 on a weighed filter, calculate from weight of precipitate containing 1.66 per cent. P. Total Carbon. — Take 5 gms., treat with 120 c.c. of a solution con- taining 280 gms. 2 NH^Cl, CuCl.^ per liter ; warm and stir, but do not allow the solution to boil. Decant the clear liquid through asbestos in a piece of combustion tubing, drawn out (Elliott). Digest the mixture of copper sponge and carbon with more of the solution to which HCl is added. Finally transfer the carbon to the filter, and wash thor- oughly. Convert to CO, for weighing, by (Ullgren, Elliot) method-wet combustion with H^SO^ and CrO„ passing the evolved gases through AgjSOj. The colorimetric method for combined carbon in steel is de- scribed: 0.2 gms. of the steel and of the standard are taken for each determination. Artificial comparison solutions are asserted to be use- less. When the action ceases, immerse for 15 minutes in boiling water, then cool, and compare in calibrated tubes. ABSTRACTS. 63 Graphite, — 5 gras. of sample, 60 c.c. dilute HCl, and when solution is nearly complete, add 20 c.c. strong HCl and digest further ; then dilute largely, filter on weighed filter, wash with water, KOH solution, then alcohol, then ether, dry and weigh. Ignite off graphite, and weigh residual SiO„ etc. Sulphur. — The uncertainties of evolution methods are noted. Of evolution methods, the passage of the gas through 220 c.c. CuSO^ solu- tion containing 60 gms of the crystals per litre, is recommended. For precipitation, the filtrate from silica {vid. Silicon) is evaporated with HCl, to remove nitrates, and excess of HCl and precipitated by BaCl2t allowed to stand 12 hours and filtered. No special directions as to tem- perature of the solutions are given. Copper. — 10 gms. digested with 100 c.c. aqua regia, and evaporated to dryness ; redissolve in a little HCl, and evaporate to dryness a second time. Filter, make up to 250 c.c. ; reduce Fe by excess of Na^SO,, boil out SO,, precipitate with H^S, let settle, dissolve in HNO, and pre- cipitate with NaOH ; weigh CuO. Or, dissolve 10 gms. in 100 c.c. HjjSO^ (i : 3), boil, add 6 c.c. of strong solution of Na^SjO,, boil (with stirring) for about 30 minutes ; filter, dissolve precipitate in aqua regia, evaporate with 10 c.c. strong H,SO^ to fumes. Dilute, boil, add excess of ammonia, let stand ; filter, and Irom the filtrate precipitate Cu by Na.^S„03; ignite and weigh CuO. For minute quantities, dissolve 20 to 50 gms. of the sample in aqua regia, evaporate nearly to dryness, digest with ammonia, and use color- comparison test. ' Tungsten, — Conduct the operation as described for silicon, avoiding, however, the use of so high temperatures in effecting solution or in dry- ing, since that renders WO, imperfectly soluble in the subsequent treat- ment with ammonia. Filter off SiO.^ and WO,, wash, and then dissolve out VVOg with ammonia into a weighed platinum dish, evaporate to dry- ness, heat to decompose the salt ; finally ignite and weigh WO,. If on Oxide. — Digest lo gms. at a gentle heat (200 to 212° F.) with stirring, in 500 c.c. of a mixture containing one part H,SO^ and 6 parts saturated solution of K^Cr^O,. When all of the metal has been dis- solved, let stand to settle, wash three or four times by decantation ; then digest with KOH solution to remove SiO.^ ; dilute with water, transfer the precipitate to a filter ; wash first with dilute KOH, then with water, dry, ignite, and weigh. FCjO^ is the form in which the oxide exists in the iron. Titanium. — Riley *s method : treat 6 gms. with 100 c.c. aqua regia, evap- orate to dryness, heat strongly, moisten with HCl and dry again ; add HCl and dissolve by aid of heat. Dilute and filter ; set filtrate aside until the TiO, in the insoluble portion is brought into solution by fusion with KHSO^, pulverization, and extraction with cold water. Filter off insoluble SiO^, and unite the solutions. Reduce iron by Na^SO,, boil out SO5, nearly neutralize with ammonia, add NH^C^HgOj. Boil, filter rapidly, wash and dry. Fuse with 6 parts KHSO^, dissolve in cold wa- ter ; nearly neutralize, add a little Na^SO,, dilute, boil some hours, let settle, filter, wash first with very dilute H^SO^, then with water ; dry, , ignite and weigh the (somewhat hygroscopic) TiO.^. In pig-irons, take 20 gms. of the sample, digest with 150 c.c. dilute HCl. When the iron is near'y dissolved, add 100 c.c. of strong HCl, and boil for some time. 64 THE QUARTERLY. Dilute, filter off SiO.^, TiO^ and graphite. Wash with dilute acid, then with KOH to remove sihca, then with dilute acid to remove the alkali. Dry, and fuse with KHSO^, treating as before. Manganese, — Dissolve 2 gms. in 50 c.c. of aqua regia by the aid of heat. Transfer to a capacious flask, dilute to 1500 c.c, heat to boiling, neutralize with strong ammonia until a faint permanent turbidity is pro- duced, then add 250 c.c. of hot NH^C^HgO.^ solution, boil, let stand to settle, filter and wash with water containing a little of the acetate. If the filtrate is turbid, boil up again for five minutes, when it will filter clear. Concentrate to 400 c.c. Cool, add Br until the solution is strongly colored, then render strongly animoniacal, and boil to precipi- tate MnOj. Wash and ignite strongly to MnjO^. Weigh. Test the precipitate for iron, which, if present, must be estimated (as Fe^Og and deducted). The estimation may be colorimetric with NH^CyS, or by dissolving and repeating the basic acetate separation. Cu or Ni are also possible contaminants of the precipitate. The chlorate method is mentioned as an alternative method (essen- tially Ford's, using the ammoniacal basic acetate separation). 4 gms. are dissolved in 60 c c. HNO, (gr. 1.2), then 30 c.c. HNO^ (gr. 1.42) is added, and after bringing to a boil, 6 gms. KCIO,. Boil 15 minutes, cool, dilute, let settle, decant the clear liquid through a filter, dissolve in HCl, dilute with 200 c.c. of water, separate remaining iron as basic acetate, and precipitate out Mn by Br, as before. In spiegels and ferromanganese the Mn can be estimated by difference (?) ; determining the iron volumetrically, and allowing also 6 per cent, in spiegels, and 7 to 7^ per cent, in ferromanganese, for C, Si, etc., call the remainder Mn. Arsenic is separated as sulphide together with copper (^. z/.). Digest the sulphides with KHS solution, filter, precipitate as sulphides from the solution by HCl, dissolve in aqua regia, add a little magnesia mix- lure and much ammonia, let stand 24 hours, collect on a weighed (?) filter, dry and convert to yi^^k^fi^ by ignition. The magnesia mixture is to be made by mixing a solution of Zt^ gms. each of MgSO^ and BaClj and 5 c.c. cone. HCl in sufficient water, adding eventually a slight ex- cess of MgSO^. Filter, add 165 gms. NH^Cl and 260 c.c. ammonia; dilute to one litre, let settle and decant. Chromium. — No good methods exist. One given consists in dissolv- ing, separating Si0.^as usual, precipitating by ammonia, fusing the mixed oxides with alkaline carbonate and nitrate, leaching out with water, re- ducirg the chromate with HCl and alcohol, and precipitating with am- monia. Another consists in dissolving i to 2 gms. in HCl in a platinum dish, evaporating, fusing directly with alkaline nitrate and carbonate, and treating as before. For steels Galbraith's volumetric method is recommended, dissolving in H.^SO^, oxidizing up with K^M^Og, then reducing chromate by use of a known amount of FeSO^ solution, and titrating the excess. The use of colorimetric comparison tests of Cr^Oj solutions is mentioned. The methods for Al, Ca, Mg, Ni and Co do not merit special men- tion, being essentially the older and more elaborate methods of several years back, and, like most of the others, unsuited to the demands ot our metallurgical laboratories. ABSTRACTS. 65 S/ag antifysrs. Textor (y. Afta/. App, Chem,, vii., 257), describes the methods used in the laboratory of the Cleveland Rolling Mill Company. The determinations are made daily, and only approximate results are . 3imed at. For Si O.^ and A 1^0^^ 0.5 gm. is taken, stirred up with hot water, then decomposed by addition of HCl, stirring until decomposed. The mix- ture is then evaporated ; when low, a few drops of HNO, are added and ' the evaporation continued to dryness, when it is heated strongly to separate SiO^, taken up with HCl, etc. The filtrate is precipitated by ammonia added gradually; and the precipitate is weighed and reck- oned as AL^Oj. For CaO and MgO^ another portion of 1.325 gms. is decomposed in the same manner as above, and without filtering or evaporating to dry- ness, ammonia is gradually added to precipitate Al^Oj,, SiO,, etc. The mixture is made up to a definite volume and two separate portions taken —the one for CaO, the other for MgO. In both portions CaO is pre- cipitated out by oxalate. The filtrate intended for MgO is allowed to cool while the other CaC^O^ is dissolved in hot dilute H2SO4 and titrated with permanganate. The MgO solution is precipitated by ammonia and I'hosphate, agitated cold ten miriutes and then filtered. The filter is dried, the paper separated from the precipitate and incinerated first, then the precipitate added, and the whole ignited and weighed. For S another portion of 0.5 gm. is stirred into 150 c.c. of water, >tarch added, and it is then decomposed by HCl, adding measured amounts of a standardized solution of iodine, the iodine solution being eventually added until the starch shows the end reactions. • Many of the details given are necessarily omitted. Portland Cement. R, and W. Fresenius {Fres. Zfs. Anal. Chem.^ xxxii., 433). The chemical characters of a good Portland cem^int are given as to Hows : 1. Specific gravity before ignition, at least 3. 2. Specific gravity after ignition, at least 3.12. 3. Loss on ignition, at most 3.4 per cent. 4. Alkalinity of aqueous solution from 0.5 gm. of cement, not over 7.2 c.c. of tenth normal acid. 5. Potassium permanganate destroyed by i gm. of cement, not over 2.N mgs. 6. MgO, not over 3 per cent. Analysis of Boro-natro calcite andofPandermit, Gilbert {Zts. Angew. Chem., 1893, 53O. For H,^0, ignite 5 gms. in a covered porcelain cru- uble to constant weight for S, and boil up 10 gms. with 50 c.c. HCl and 100 c.c. H,0. Filter and weigh residue. Dilute the filtrate to 500 c.c. Evaporate 100 c.c. with 5 c.c. Dilute K^SO^ (i : 2) in a weighed platinum capsule, addjng about 20 c.c. of 40 per cent. HF, heating finally to fusion. Ignite and weigh the mixture of CaSO«, MgSO^, Na.^- SOj, Fe^O, and Al^O.,. Dissolve in dilute HCl, and determine Ca, Mg, FcjOg and Al^O,. as in a limestone analysis. In another 100 c.c. deter- mine SO3 and reckon Na.,SO^ from the weight obtained as well as from the weight of the combined sulphates, etc. VOL. XV. — 5 66 THE QUARTERLY. Eur Chlorine, dissolve 2 gms. in dilute HNO3 and apply the Volhard method. For CO, the ordinary method by loss. P^Oj is ordinarily absent or present in exceedingly small amounts. The B2O3 is reckoned by difference. A more direct m>ethod of determining ^.f)^ is given. Rub up 2 gms. of the mineral with 50 c.c. (NHJ.^COj, (Fre^enius^s reagent), let stand two hours, filter, evaporate the filtrate to dryness in platinum, ignite off NH^ salts, dissolve the residue of borate with about 5 c.c. of normal acid and 20 c.c. of water, add methyl-orange, and titrate back with fifth normal soda. Reckon the soda as Na^O, 2 B,Os the lime as 2 CaO, 3 B2O3 in Boronatro calcite. The formula of Pandermite is asserted to be 4 CaO, 5 B^Oj, 7 HjO, and not what is usually given (2 CaO, 3 B^O,, 3 H^O). Direct methods for determining BjO, as given by Rosenbladt, Gooch and Moissan are condemned as complicated and troublesome. Micro-chemical Analysis of Rocks. Frey {Abs, in Chem, News, Ixviii., 277), cements fragments to a slide with Canada balsam, and then touches with a drop of HF, allows the solution to evaporate, and examines with a microscope. Na gives crystals of the hexagonal system, K tesseral rubes, Ca spindle-shaped tissues, etc. The silicofluorides of Fe, Mn and Mg thus produced resemble one another rather closely, but on touching with a drop of CI water, Fe crystals turn yellow, Mn red, while those of Mg remain colorless. Separation of Minerals, Retgers {/ahrb.f Min., 1893, i, Mem. 90), proposes the use of fusing thallium silver nitrate. TlAg (N0g)2. 'J'he salt fuses at 75° C, and in this condition has a specific gravity of 5. It can therefore be fused on a dish over a water-bath, and in it minerals having a specific gravity greater than 5, as magnetite, etc., will sink. Metallurgy, by Joseph Struthers. Fuels. — Washed coal for coking. — Amer, Manuf, August 4 and 18, 1893. Fuels. — Manufacture of coke. By Fulion. — Colliery Engineer, August, 1893. Fuel. — The consumption of fuel in the Taylor gas-producer plants at the Aspen and Marsac mills compared. By C. A. Steiefeldt. — Advance sheets, Trans. Amer, Inst, Min, Engs., August, 1893. Fuels. — Petroleum and other fuels. By W. H. Wakeman. Paper read before the Elm City Stationary Engineers* Association of New Haven. A general discussion of fuels giving type fuel with average composition and calorific value. The samples taken for comparison are as follows : Durham Coke. — Composition, about 94 per cent, carbon ; contains 13.640 heat-units; requires 11 pounds of air for complete combustion, the rise in temperature being 4877^ F. ; maximum amount of water evaporated is 14.12 pounds for each pound of coke. Bituminous Coal. — Good grade. Composition, over 81 per cent. ABSTRACTS. 67 carbon ; contains 14.143 heat-units; requires 11 pounds of air for com- plete combustion ; the rise in temperature is 4830° F. ; maximuni amount of water evaporated is nearly 15 to i (stated to be an exceptional case). Illuminating' Gas, — Composition, about 61 per cent, carbon; con- tains 20.800 heat-units; requires nearly 16 pounds of air for complete combustion per pound ; the rise in temperature is 4567*^ F. Each pound of gas will evaporate more than 21 pounds of water. Oak Wood Kiln-dried, — Composition, about 50 per cent, carbon ; contains 7713 heat-units per pound ; requires 6 pounds of air for com- plete combustion, giving a rise of temperature of 4287° F. Each pound will evaporate 8 pounds of water ; wet and green sawdust containing 55 per cent, of moisture and 45 per cent, of wood develops 2916 heat- units, giving a rise of temperature of 2245^ F., and will evaporate 4 pounds of water per pound of wood in the fuel, but for each pound of luel as it stands the amount is very much less. Crude Petroleum. — Composition, about 85 per cent, carbon ; develops 20.360 heat-units; requires 15 pounds of air for complete combustion, giving a rise in temperature of 4900** F., and each pound of oil will evaporate 21 5 pounds of water. Ii must be remembered that in each of the above cases the theoretical evaporation is given, and from this a deduction must be made for heat lost by radiation, etc., and the actual quantity of air passed through the fuel will be much greater. These figures, however, will answer for the purpose of comparison. Good authorities claim that in actual use one pound of petroleum will evaporate from 25 to 50 per cent, more water than anthracite and from 60 to 100 per cent, more than bitumin- ous coal. Special points in favor of the use of crude petroleum are less bulk for storage, less labor in handling, and no ash. — Amer. Manuf,^ October 13, 1893. Fuel. — Coking ovens (editorial review of Consul Mason's report on improvements that save the waste products, and cheapen the cost of coke making nearly 40 per cent.). Average German coal furnishes about 76 per cent, of coke, i J^ per cent, ammonia, and 2j4 to 4 per cent, of tar, the remainder being gas and water. As the sulphate of ammonia is worth about 2^ cents per pound and tar }4 cent, while the gas takes the place of coal for heating the retorts, it is found that a battery of 60 ovens besides saving on the average 8000 tons of coal a year as fuel over the old process, produces 800 tons of sulphate of ammonia worth about$42,000, and 3000 tons of tar worth about ^28,000, all of which would «
be wasted by the old process. — Amer, ^r^^/y<?r/, September 16, 1893.
Blast. — Automatic Valve Gear for Blowing Engine. By James C.
Brooks. Illustrated and descriptive. A paper presented at the World's
Engineering Congress before the American Institute of Mining Engi-
neers. — Iron Age, September 7, 1893.
Bi-AST. — The Philadelphia Corliss Blowing Engine. Illustrated and
descriptive. — Iron Age, June 22, 1893.
Blast. — Blowing Engines. By Julian Kennedy. Illustrated and
68 THE QUARTERLY.
descriptive. — Advance sheets, Trans, Amer. Inst. Min, Engs., August,
1893 ; Iron Age, August 27, 1893.
Blast. — The Buffalo Steel Pressure Blower. Illustrated and descrip-
tive. — Iron Age, May 11, 1893.
Tuyeres. — The Evolution of the Tuyere Stock. By Fred. W. Gordon .
Illustrated and descriptive. — Iron Age, June 8, 1893.
Pyrometer. — Le Chatelier's pyrometer. By R. K. Gratinny. Notes
regarding use. — Eng. and Min, /our., September 23, 1893.
Ores. — The separation of blende from pyrites ; a new metallurgical
industry. By William P. Blake. — Advance sheets, Trans. Amer. Inst.
Min. Engrs.^ August, 1893; Eng. and Min. Jour., August 19, 1893.
Blast-Furnace. — The calculation of limestone charges for iron
blast-furnaces. By S. P. Bjerregaard.-:-/ri?« Age, October 5, 1893.
Blast-Furnace. — Combustion at the tuyere level theory. By W.
von Volten. From Stahl und Etsen. — Iron Age^ October 5, 1893.
Blast-Furnace.— Improved internal form of blast-furnace. Messrs.
Hawson and Harndon advocate the use of higher bosh, claiming in-
creased production and lower fuel consumption. Colliery Guardian,
August 25, 1893.
Slag. — General solution of the type slag problem. By J. L. Saint-
Dizier. Our purpose is to form a slag of the formula, SiO.^ (CaO, FeO).
Having given the ore, let us call ;
A =8 the percentage of SiO^ in the ore.
1 going into the slag.
B »
" FeO
t
E =
" CaO
D«
" MgO
H =
'' BaO
K»
" AlA
L =
** ZnO
We know that MgO, BaO, Al^ and ZnO may replace CaO in the
slags. As MgO z= 1.4 CaO ; Bad = .366 CaO ; A1,0, = 1.647 CaO ;
and ZnO = .691 CaO; then the equivalent of CaO will be (letting C =
this equivalent) :
C= E + 1.4 D + .366 H + 1.647 K + .691 L. (i)
The fluxes have the following compositions :
Iron Ore : a = percentage of SiO^ ; b = percentage of FeO.
Limestone : c = percentage of SiO, ; d = i)ercentage of CaO.
If the limestone contains MgO, Al^Oj, etc., its equivalent in CaO
may be calculated as in equation (i).
Let X be the number of tons of iron ore required by 100 tons of ore.
Let y be the number of tons of limestone required by 100 tons of ore.
ABSTRACTS, 69
Then : A_ (A + — + ^ ) = 2 (. + - — ) (2)
60 100 100 72 7200
And : .3J (a + .^-^- + -1^- ) = 2 C'^^- + 'f y) (3)
60 100 100 56 5000
.p, , 14a (looB — 120A) + (i2oa — loob) (14A — 15C)
I4bc+ i5d (1.2a — b)
looB — 120A — i.2cy
1.2a — b
■—State School of Mines Scientific Quarterly , June, 1893.
And : x =
1.2a — b
Pig- Iron. — Machine for breaking pig-iron, and loading it into cars.
Illustrated and descriptive. — Iron Age, July 6, 1893.
Iron. — German economy in iron manufacture. By Frank H. Mason.
— U. S, Consular Reports^ August, 1893.
Foundry Practice. — The centre-blast tuyere cupola. By Thomas
D. West. Illustrated. — Iron Age, October 26, 1893.
Iron Cupolas. — Their construction and management. By W. J.
Keep. — Iron Age, June 8, 1893.
Iron Puddling at Lowmoor. By E. W. Richards. — Iron Age, July
J5» 1S93.
Mill- Work. — Rod rolling-mills and their development in America.
By Fred. H. Daniels. — Iron Age, August 10 and 17, 1893.
Hammer. — The 125-ton hammer of the Bethlehem Iron Company.
Abstract o{ article in ** Engineering.'* — Eng. and Min, Jour,, October
7, ^^9Z'
Steel. — The Open-Hearth process. By H. H. Campbell. Descrip-
tive and illustrated. — Advance sheets, Trans, Amer, Inst. Alin, Engs.,
\ August, 1893; Iron Age, August 24 and 31, 1893.
Steel. — Details of the Siemens-Martin furnace, a chemical and calori-
raetric study of gas generation and its application to the Siemens fur-
nace. By Frederick Toldt, — Berg, unci Huttenmannisches Jahrbuch of
X, K. ^ergakademien zu Leoben und Pribram, vol. xli., parts 3 and 4.
Steel. — The Bessemer process as conducted in Sweden. By Prof.
Richard Akerman. Illustrated and descriptive. — Advance sheets, Trans,
Amer. Iftst. Min, Engrs,, August 1893 \ ^^^n Age, September 28th, Oc-
tober 5 th and 12th; Eng, and Min, Jour, ^ July 29, 1893.
Steel. — Basic steel manufactured at Witkowurtz, Moravia. By Paul
Kupelwieser. Abstract of paper read before the Iron and Steel Insti-
tute. Err^' and Min, Jour.^ October 14, 1893.
70 THE QUARTERLY.
Steel. — The regulation of the temperature in the converter. Com-
munication to editor. By John E. Fry ; also by H. H. Campbell. — Iron
Age^ August 31 and September 7, 1893.
Steel. — The microstructure of steel. By Albert Sauveur. Illustrated
and descriptive. — E, and M. J,y August 12, 1893.
Steel and Iron. — Segregation and its consequences in ingots of steel
and iron. By Alexander Purcel. — Advance sheets, Trans^ Amer. Inst,
Min, Engrs.^ August, 1893 ; Iron Agd, August 10, 1893 y Eng. and Min,
Jour.y September 2, 1893.
Iron and Steel. — The desulphurization of iron. — Londttn, Eng,,
June 2d, and Engineer^ June 2d, and Eng, News, July 6, 1893.
Iron and Steel. — Iron and steel at the Columbian Exposition. De-
scriptive. — Iron Age, May i, 1893.
Iron and Steel. — Proposed combination of the blast-furnace and
the Bessemer converter. By John Hollvvay. — Iron Age, October 12,
1893.
Iron Alloys. — With special reference to manganese steel (an Engi-
neering Congress paper). I. Iron ; reviewing the Beta-iron theory and
the effect of carbon ; allotrophy. II. Carbon; carbon and iron; car-
bon in cast-iron; investigations. — Industries and /r^^, September i,
1893.
Copper. — The Treatment of Lake Superior Copper Ores. By F. F.
Sharpies. Method adopted at the Atlantic Mill, — The Technic^ 1893.
Lead and Copper. — Improved Slag-pots. By H. A. Keller. Illus-
trated and descriptive. Advance sheets, Trans, Am, Inst, Min, Eng.y
August, 1893.
Silver Lixiviation. — The Russell Process, by L. D. Godshall, gives
the following notes as embodying the essential features of the Russell
process :
First, — Fine crushing is necessary in many cases.
Second — Stamps are the most reliable, and at the same time most
economical, for fine crushing, while rolls are generally preferable to pul-
verizers.
Third. — The furnace best adapted to chloridizing silver ores depends,
at all times, upon the character of the ore. The Stetefeldt furnace is
probably the most economical furnace for ores high in silica, free from
lime and magnesia, and low in sulphur. For ores containing 3 to 8
per cent, of sulphur, the Brtickner, Pearce, or Howell-White furnace, is
to be recommended. For ores containing over 8 per cent, of sulphur,
unless accompanied by a very large excess of lime, the reverberatory fur-
nace, or a combination of two furnaces, the first of which should be de-
voted exclusively to an oxidizing roast, will be found to be most eco-
nomical.
ABSTRACTS. 71
Fourth. — The loss by volatilization is principally a function of time
and amount of oxygen in contact with each particle of ore while in the
act of chloridizing.
Fifth. — The leaching of the ore depends to a great extent on the
roasting of the same. A poorly roasted ore will only give good results
by tbe Russell process by the expenditure of a large consumption of
chennicals and time. Different strengths of solutions and different
methods of application will also in some cases improve the percentage
of extraction, but with good roasting and a sufficient amount of solu-
tion, the extraction will be good, no matter how the solutions are ap-
plied.
Sixth. — The precipitation of the silver by means of sodium sulphide
presents no difficulty, and is much to be preferred to calcium sulphide.
Seventh. — The economical refining of the sulphides at the mill is a
problem which is not yet satisfactorily solved ; and,
Fighth. — That the Russell solution is capable of dissolving certain
comiX)unds of silver which cannot be dissolved by sodium hyposulphite
alone, and is capable of extracting from 90 to 95 per cent, of the silver
in ordinary dry ores, when the silver is not present in the metallic state,
but that a high extraciion of the silver will not necessarily make the
process a commercial success in all cases.
The greatest objection to the Russell process is the cost of treating
the ore — a very expensive plant is always required. The loss in roast-
ing is also a serious matter,, as is the case in all chloridizing-roasting
processes. Notwithstanding these objections, there is no question but
that there are numerous localities in the West where the introduction of
this process would prove a profitable investment. This statement being
based on a cost of treatment of Jio per ton, for a mill of 100 tons daily
capacity, and $12 per ton for a mill of 50 tons daily capacity, with a minimum extraction of 90 per cent, of the silver in comparison with current smelting rates on dry ores, with added freight charges. — State School of Mines Scientific Quarterly^ June, 1893. Silver Lixiviation. — The sulphuric acid process of refining lixivia- tion sulphides" By F. P. Dewey. The pr^.ctice as used at the Marsac refinery at Park City, Utah, consists in boiling the sulphides from the Russell process in strong sulphuric acid in an iron pot ; removing the charge when cool to a lead-lined tank; adding water; filtering; pre- cipitating the silver on copper ; removing, sweetening, and melting the cement silver; recovering the sulphate of copper by crystallization and treating the pot residues for the recovery of gold. The charge is about 600 pounds of sulphides, carrying about 28 per cent, copper and 2^7^ per cent, silver. This is put in an ordinary parting pot, with about two and a half times its weight of strong sulphuric acid and the pot heated. If the temperature is kept low, there is an evolution of yellow fumes, and the reaction may be summed up, 3Cu'} ''^ + 4H,S0, = Jgj, I SO. + 4H.O + 4S (the actual reaction is somewhat complicated). As the heat is raised, the fumes grow lighter colored, and the reaction may be taken as 72 THE QUARTERLY. C^' } S + 3H.SO. = Jf« } SO, + 3SO, + 3HP. Boiling is continued until the residue in the pot is light colored. By the boiling the sulphate of silver is readily dissolved by the excess used, while the sulphate of copper is, for the most part, insoluble in th^ acid. The treatment of the residue is carried out in a lead-lined tank 4' X 8' X 2', heated by blown in steam. The sulphate of copper is dissolved. The insoluble residue is allowed to settle, and the sulphates of copper and silver are drawn off through a filter to the precipitating tank, 7' X 9' X 3'. also lead-lined. The residue is brought on the filter and washed. The silver is precipitated on copper and the copper sulphate is crystallized. The cement silver is washed, dried, pressed, melted with a little borax and nitre in graphite crucibles, yielding a high-grade bullion over 997^^ fine. The residue contained in the first filter, consisting of sulphide of silver free from copper, sulphate of lead, a little sulphur, and small amounts of other insolubles, is boiled again to separate the silver, leaving the gold in a small amount of final residue, consisting mainly of sulphate of lead. This final residue is melted with nitre and borax to recover the gold. Details of the pots, arrangement of works, and acid transportation are included in the article. — State School of ^ Mines Sciennfic Quarterly^ Golden, Colo., June, 1893. Silver-Ore Roasting Furnace. — The Pearce Turret Furnace. The furnace consists of an ordinary reverberatory hearth, built in a circular or turret-shaped form. In the circle formed by the brick work is placed the iron work, consisting of a central vertical column with 4 pipe-arms horizontally radiating from same, and projecting through slot over re- verberatory hearth ; to provide for this slot, through which the pipe- arms project and along which the arms travel, the inner side of the arch is hung from ** I '* beams. The ore is mechanically fed, and is moved along the hearth by the rotating pipe-arms, holding rubble blades, and is discharged automati- cally, falling by gravitv into a pocket. Air is forced through the hollow pipe arms and discharged against the rubble blades, thus cooling the iron work and furnishing heated air for the roasting. Two or more fire- places may be used. The space under the hearth is utilized as a dust- collector. One man per shift is sufficient to run this furnace. Its first cost is much less than the Briickner and other mechanical roasting furnaces of same capacity. Repairs are limited to the removal of rubble blades and can be rapidly made. A 36-foot furnace has a capacity, on pyritic ores, of 20 tons daily ; on ores requiring to be chloridized it has roasted 9 tons daily to an average of .22 of i per cent., with the special advantage that salt could be added at any stage of the process desired, thereby saving values otherwise lost by volatilization. — State School of Mines Scientific Quarterly y June, 1893, Silver. — Treatment of complex zinc-ores, by F. L. Bartlett : Gives ABSTRACTS. 73 the method of extraction pursued by the American Zinc-Lead Com- pany at Cafion City, Colorado. The process may be summarized as follo"ws : I. — Blowing up mixture of zinc-ores, crushed to pea- and dust-size, with 75 per cent, of fine coal. Average contents : Zn, 30 per cent. ; Pb, 8 per cent. ; FeS and SiO, to balance ; Ag, 10 to 20 ounces ; Au, -^^ ounce ; Cu, i to 2 per cent. Treatment by blowing up on a perforated grate by heavy air-blast, eliminating a large proportion of the lead, zinc and sulphur. The pro- cess is stopped before the sulphur contents are too much reduced, thus retaining the silver. A cinder or scoria is formed, which retains nearly all the gold, silver and copper. Time of blowing, 4 hours. Results : Fume (ji) and cinder {b): II. — Treatment of Cinder. — Cinder (^) contains ZnS, 12 to 15 per cent. ; Pb, i per cent. ; Ag, 10 to 20 ounces ; Cu i to 8 per cent. ; bal- ance, FeO. FeO,SiO,. FeS., etc. This is mixed with 5 per cent, of lime, and any copper-ore added which may contain Ag, Pb, Zn, Fe, S and SiO^. If too siliceous, iron fluxing ore is added. This is smelted in a blast-furnace with a small per cent, of coke. Result : Fume (a), slag (<r), matte (//). III. — Fume Treatment. — The fume, which is collected in woollen filter bags, is submitted to the roasting and grinding process, and is sold as pigment. The impurities drawn off contain a mixture of As, Sb, Hg, Fe, SO.^, Cd, and many rarer elements. The pigment contains 4 to 5 ounces of silver per ton. IV. — Slag fr) is thrown away. This contains .75 ounce Ag ; 2 to 7 per cent, of Zn ; and no lead or gold. V. — Matte (//) is either refined on spot or sold for refining ; contains 75 to 200 ounces of Ag. ; -5^ to J^ ounce gold ; 30 to 40 per cent. Cu, and 2 to 4 per cent. Zn. The process requires experience in working, especially if pigment is to be made, as the slightest color will injure its sale. The matting fur- naces require quite a different treatment from those used in copper- and lead-smelling. The great excess of zinc and sulphur, together with silica in excess, makes a difficult charge to run, which, if attempted in the ordinary blast-furnace in the usual way, would almost instantly freeze the furnace. Success in working this scheme depends largely on experience and practice. — State School of Mines Scientific Quarterly, Golden, Colorado, June, i«93. Gold. — The limitations of the gold stamp mill. By T. A. Rickard. Descriptive. — Advance sheets of the Trans, Amer^ Inst. Min, Engs.^ August, 1893. Aluminum. — By R. L. Pacard. — From Bulletin^ of the U. S. Geolog- ical Survey, April, 1893 ; Journ, Amer, Chem, Soc, April and May, 1893. Al. — The metallurgy of aluminium. By John W. Langley, Ph.D. The electrical expenditures are frorii 5000 to 7000 amperes, which go through all the pots in series with a drop of potential of 7 volts for each 74 THE QUARTERLY. pot. The actual E. M. F. of decomposition of alumina is about 2.3 volts, the difference between this and the 7 volts necessary being due to the internal resistance of the bath and the carbon linings. The produc- tion of I pound of aluminum takes 18 horse-power hours measured at the steam engine ; about 1500 pounds are produced daily. — The Technic^ 1893. Antimony. — The extraction of antimony by electrical methods. Abstract of C. A. Hering*s review of the different processes, published in Di'gler's Polytechniches journal, 268. — London Electrical Review^ August 25, 1893. Metals. — Specific heats of metals. By Jos. W. Richards. Discus- sions under the head of i. Definitions, 2. Methods, 3. Historic treat- ment ; The investigator ; Work done by each. 4. Discussion of the results; Tables; Diagrams and formulae. 5. Theoretical treatment, discussion from the chemical and mechanical standpoints. — y^ourn. Frank, lusty July and August, 1893. General Summary of American improvements and inventions in ore-crushing and concentration and in the metallurgy of copper, lead, gold, silver, nickel, aluminium, zinc, mercury, antimony, and tin. By Jas. Djuglas. — Advance sheets of Trans. Amer, Inst. Min. Engs.^ August, 1893. Electro-Metallurgy. — By F. Osmond (abstract of paper read before the Engineering Congress). The microscopic study of metals shows crystallization to some extent in all the metals. Crystalline forces on the one hand and tensions and compressions on the other, determined by inequalities of temperature in the mass during heating or cooling give rise in every metal to the formation of geometric elements of struc- ture. — Industries and Iron, August 18, 1893. BOOK REVIEWS. A Text-Book on CoAL-MrNiNO, for the Use of CoLLrERY Managers and Others. By Herbert W. Hughes. Large 8vo. 436 pp. 490 cuIn Index and Bibliography. London and Philadelphia. 1893. Since the formation of the North of England Institute of Mining En- gineers, forty years or more ago, seven or eight similar institutions have been organized in other counties of England, Scotland, and Wales, and there has been accumulating a most voluminous and valuable literature relating to mining, in the transactions of these societies. This mass of material has been exploited from time to time, chiefly with the scissors and paste-pot, and sundry ponderous volumes on mining have been pro- duced. These volumes, however, have been edited with but little judg- ment, and for this reason have small value, in spite of their bulk and pretensions. Mr. Hughes has made much better use of this material, and has, with great labor, given us in a compact volume a most valuable epitome of this mass of literature. Mr. Hughes has drawn, also, from the journals and transactions of this country, and from those of some of the coun- tries of Europe, and very largely from his own experience. As a graduate of the Royal School of Mines, a past-president of the British Association of Mining Students, a practical colliery manager, and the author of numerous papers on coal-mining, Mr. Hughes is sin- gularly well fitted for the work he has accomplished, Mr. Hughes's work contains chapters on Geology, Coal, Search for Coal, Breaking Ground, Sinking, Preliminary Operations, Methods of Working, Hauling, Winding, Pumping, Ventilating, Lighting, Works at Surface, and the Preparation of Coal for Market. The first two chapters are quite short ; the others average about thirty- five pages each, and the space is very well apportioned among the dif- ferent subjects. Ekich chapter ends with a bibliography giving a list of the more im- p>ortant papers on the subject which have appeared in the transactions of each of the mining societies, or in the leading mining journals, with occasional references to special treatises. This has been done already for German mining literature by Professor Kohler, in his Bergbaukunde^ and less completely by Professor Haton, for French transactions and journals, in his Exploitation des Mines, The very valuable mass of ma- terials in the transactions of the English societies is now for the first time made available. This bibliography adds much to the value of the book, especially as many important subjects have been treated in outline only, in order to keep the book within moderate limits. The author has occasionally erred on the side of over-condensation and conciseness. This, how- ever, is a most refreshing innovation in mining treatises, and one with which we are not disposed to find fault. The book is illustrated by numerous small cuts in the text, specially drawn for the book. Many of these cuts are rather crude in drawing, and all of them have suffered in reproduction, so that the general effect o( the book is somewhat marred, especially when compared with such treatises as Haton and Kohler. The cuts, however, are clear and ad- mirably illustrate the text. 76 THE QUARTERLY. The book, as a whole, is the most valuable treatise on mining that has appeared in recent years. Over two-thirds of the book treats of subjects of interest to those engaged in metal-mining, so that the work will prove a welcome addition to the library of all mining engineers. H. S. M. Lecture Notes on Theoretical Chemistry. By Ferdinand G. Wiechmann, Ph D. First Edition. John Wiley & Sons. New York. 1893. 8vo., 225 pp. Cloth binding. Typography and paper of good quality The author discusses the subjects in the following order : Chapter I. — Introduction and definition. 11. — Specific gravity. Methods of determining the specific gravity of solids, liquids and gases, with calculated examples under each head. III. — Chemical nomenclature and notation, giving the various earlier systems, and concluding with a summary of the rules for the spelling and pronounciation of chemical terms as adopted by the American Association for the Advancement of Science in 1891. IV. — Atoms, atomic mass and valence, Ihe various methods of deter- mination are presented by calculated problems affording good illustra- tions of the different methods. V. — Chemical formulae. VI. — Structure of molecules, discusses molecular volume, refraction, and the magnetic rotation of the plane of polarized light and stereo- chemistry. VII. — Chemical equations and calculations. VIII. — Volume and weight relation of gases, with methods of analysis. IX. — The periodic law, giving the tables of Newland, MendeleefT, and Lothar Meyer. X. — Solutions. XI. — Energy — chemical affinity. XII. — Thermal relations — thermo-chemistry. Giving the determina- tions of specific heat, calorific power and intensity, and the laws of thermo- chemistry. XIII. — Photo-chemistry, discusses chemical union and decomposi- tion, physical changes, mode of action, and the measurement of the chemical activity of light. XIV. — Electro-chemistry, describes electrolysis, the Ion theory, electrical units and quantitative relations. For a general view of the subject of theoretical chemistry this work is to be commended. It is ably supplemented by a bibliography suffi- ciently comprehensive to meet most requirements. While no attempt has been made to give credit for individual articles referred to in the journal literature, the periodicals themselves are named. And in the bibliogra|)hy those books which have been consulted in the preparation of the work are specially marked with asterisks. One excellent point in the arrangement is the use, for illustration, of problems completely calculated, leaving nothing to be assumed. J. S. Miners' Pocket Books, i. The Coal and Metal Miners' Pocket- Book. — Principles, Rules, Formulit, and Tables. Compiled and prepared for the use of Mine Ofii- cials, Mining Engineers, and Students |3reparin;T themselves for Certificates as Mine Inspectors or Mine Foremen Revised and Enlarged. 565 pp. Illus- trated. Scranton, Pa.: The Colliery Engineer Co. 1893. Price, flexible covers,$2 75; cloih, %i.
2. Notes and formula for Mining Students — By John Herman Merivale, M.A., Col-
BOOK REVIEWS. 77
liery Manager, Professor of Mining in Durham College of Science, Newcastle-
upon-Tyne, etc. Second Edition. Revised. 157 pp. London: Crosby Lock-
wood & Son. 1888. Price, 2s. 6d.
3. A Tirxt'Sook of Mining Formula, — By Robert W. Dron, M E., Certificated Colliery
Manager. 62 pp. Glasgow: J. W. Morgan & Co. 1890. Price, is. Qd.
4. Afintr^ Pocket Book. — A Reference- Book for Miners, Mine Surveyors, Geologists,
Mineralogists, Millmen, Assayers, Metallurgists, and Metal Merchants ail over
the world. By C. G. Warnfurd Lock, Member Council Instn. of Mining and
Metallurgy; author of Practical Gold Mining^ etc. 472 pp. London and New
York : E. & F. N. Spon. 1892.
5. A Pocket-Book for Miners and Metallurgists. — Comprising Rules, Formulae,
Tables, and Notes for use in field and office work. By Frederick Dan vers
Power, F.G S., M.E , etc. 334 pp. London: Crosby Lockwood & Son. 1892.
Leather covers, 9s.
6. The Miners' /Ittndbook. — A handy book of reference on the subjects of Mineral
Deposits, Mining Operations, Ore- Dressing, etc. For the use of Students and
others interested in mining matters. By John Milne, F.R.S., Professor of Mining
in the Imperial University of Japan. 313 pp. London: Crosby Lockwood &
Son. 1893.
The recent appearance of a new and enlarged edition of The Coal
and Metal Miners' Pocket-Book, which heads the above list of hand-
books, has suggested grouping with it the other five for the purpose of
comparison.
Other branches of engineering have been for a long time abundantly
supplied with such publications, but, up to a very recent date, with the
exception of the two books first named, no handy works on mining and
metallurgy have been published. That there is a demand for this class
of literature is shown by the series of miners' pocket-books, which have
app)eared in rapid succession, and to which we would now call atten-
tion.
Most of them have been written with special reference to some par-
ticular portion of the broad field of mining. In one case, that of Dron's
book, the ground covered is exceedingly limited, viz., certain formulae
relating to ventilation, pumping and haulage, strength of materials,
engines and boilers, and surveying, together with a small amount of de-
scriptive matter. This unpretentious little book follows Merivale in a
way, but the latter is very much fuller, both in the number of topics
treated and in the descriptive matter pertaining to them. Merivale de-
votes considerable space relatively to boilers and transmission of power,
as well as to distinctively mining subjects, such as hoisting, drainage,
haulage, and ventilation, which are very briefly touched upon by Dron,
and closes with a useful series of examples of the applications of the for-
mulae set forth in the body of the book. In the matter of mathematical
tables, Merivale contents himself with the insertion of one only — a table
of hyperbolic or Napierian logarithms. Dron contains no material of
this class.
Lock's and Power's pocket-books both appeared last year, and are
much wider in scope than Merivale's. In Power, the first hundred and
forty-six pages are given to elementary mathematics, properties and
strength of materials, motors, hydraulics, etc., such as are usually found
in the various engineering handbooks, though more restricted in treat-
ment than similar matter as presented by Trautwine, Haswell, Moles-
worth, and others. Following these subjects are about a hundred and
fifteen pages on chemistry, assaying, mineralogy, geology, and ore-dress-
ing — material intimately connected with mining itself, but which finds
no place in Dron and Merivale. Lock, on the other hand, has omitted
78 THE QUARTERLY.
entirely the preliminary mathematics and tables, and devotes but little
space to ])roperties of materials, weights and measures, mechanics, and
allied subjects. The first hundred pages are on motive power and trans-
mission of power ; then there are twenty-three pages on prospecting and
drilling and blasting; thirty-five pages on pumping, ventilation, haulage,
and hoisting; fifteen pages on systems of mining; eighteen pages on
placer mining, gold and silver milling, with machinery specifications — all
of which are barely noticed in Power. But Power has given ninety-five
pages to chemistry, assaying, and mineralogy, and twenty pages to crush-
ing and ore-dressing, as against fifty-five and ten pages, respectively, in
Lock. Again, Lock devotes twelve pages to mine surveying, with a
traverse table of forty-four pages, carried to six places of decimals.
This subject Power omits entirely.
In Power we find a variety of useful tables, such as roots and powers,
logarithms, natural functions, circular arcs and chords, slopes, and those
under weights and measures, hydraulics, etc. Some are not so useful,
and might have been omitted, as being somewhat disproportionate in
length for so small a book. For example, there are three, occupying
thirty-one pages, and intended to lighten the labors of those who must
deal with j[^^ s. and d. : a *' Wages Table,*' on the basis of forty-eight
hours per week; a '* Table for calculating the value of silver when the
price per ounce varies between 3s. and 5s.'*; and a ''Gold Digger's
Ready Reckoner," up to values of 500 ounces, and reckoned at ^^3 19s.
and 3d. per ounce.
Another of these, page 34, is a curiosity in its way, — a "Table showing
the underlie and perpendicular in feet and inches for every degree of the
quadrant, in six feet = one fathom." The latter, however, is a short
one.
Of the two books (Lock and Power) Lock is undoubtedly the more
useful, but to both the same objection may be raised, viz., that they are
examples of the rather hap-hazard compilations of which there are such
large numbers in other branches of engineering.
Turning now to Milne, the last of the series to appear, if we except the
new edi'ion of the Coal and Meial Miners' Pocket- Book^ we find that the
author has proceeded on different lines. Milne's is a book that can be
taken up and read consecutively from beginning to end. It is essentially
a book on mining, although many important subjects are altogether
omitted. There are three parts : Mineral Deposits^ with classification and
descriptions ; Mining Operations^ under which head are placed Boring,
Breaking Ground, Systems of Working, Mine Development, and Mining
Machinery ; and Ore Dressings including Crushing, Sizing, Sorting, and
Concentration. This is all. It resembles a condensed text-book on
these subjects, and the matter is not only well arranged, but excellent
in quality. Naturally, in his limited field, Milne has been able to give
much more space than the others to the subjects of which he does treat.
Used in connection with some other book, for example, one containing
chapters on surveying, with the necessary tables, assaying and mineral-
ogy, Milne will be found very satisfactory.
fi.ially, we have an enlarged edition of the Coal and Metal Miners^
Pocket-Book, The first chapiers contain a rSsumi of mathematical prin-
ciples and rules, together with tables of weights and measures, etc. A
concise description of the ordinary methods of land surveying is followed
by the special methods employed underground, including the connect-
BOOK REVIEWS. 79
ing of outside and inside work through shafts and slopes, the establish-
ment of survey stations, systems of keeping notes, the location of errors,
etc. The magnetic survey with the dipping-needle is briefly treated,
and twelve pages are devoted to stadia measurements with tables.
Neither of the subjects last mentioned is found in any other of the books
in hand. But the special value of the book lies in one hundred pages
on the s^Titems of working coal and metal mines, with chapters on pros-
pecting. This material is presented in considerable detail — though
dealing mainly with coal minmg — and is illustrated by a large number of
good cuts. The illustrations form an excellent feature, and in introduc-
ing them the publishers have scored a distinct advance upon the other
miners' pocket-books. A chapter on the ** Location and Determination
of Faults" is also worthy of note. The article on ** Colliery Machinery,*'
by C. M. Percy, consists in part of material from the large work by the
same author, on The Mechanical Engineering of Collieries, and has
value as coming from a practical engineer and recognized authority.
The details, however, relate specially to English methods, and though
there iis no doubt that practice in England and in this country shows
some tendency to converge towards the same standanls, yet it is to be
regretted that our own practice has not been dealt with more particularly.
This might have been done in an additional chapter without greatly
enlarging the book. About two hundred pages are given to tables of
natural functions, logarithms of numbers, logarithmic sines and tan-
gents, a traverse table, etc. Besides the tables the book contains three
hundred and thirty-five pages, of which two hundred and twenty-eight
f>ages are devoted to subjects bearing directly upon mining. Some
important topics, such as geology, mineralogy, metallurgy, and ore-
dressing, have been omitted ; in fact, though there is some good material
on metal mining, the book seems to have been prepared mainly with
reference to coal mining.
But, it would be unfair to condemn books of this kind for what they
do not contain ; they should rather be judged upon the ground of what
they i/o contain. No one pocket-book can cover the whole field of
mining and its kindred subjects any more than one man can apply him-
self successfully to all branches of mining and metallurgy. Each will
have its specialties, and he wh: wishes to possess a vade mecum for his
own particular branch has, since the publication of these recent books,
good material from which to make a choice.
We have tried 16 point out their weak and strong points, and find
them generally more or less deficient — though necessarily so,, for the
reasons just given — in the fundamental mathematics, mechanics, strength
of materials, and engineering construction. They have their place,
however, and this we think, for a mining engineer, is in connection with
some such pocket-book as Trautwine, or others of tried excellence.
appended. In the first column are the topics treated, the others con-
taining the number of pages given to each. It is, of course, impracti-
cable, without entering into the minutiae of an index, to tabulate in
every case the precir>e amount of material presented under the various
heads, and some of the less important matters may have been overlooked,
but these parallel columns may be of some use in ascertaining the scope
of the books under consideration.
8o
THE QUARTERLY.
Subject.
Arithmetic and Algebra
Geometry
Trigonometry
Mensuration
Tables: Roots and Powers
Logarithms of Numbers.
Natural Functions
Logarithmic "
Circular "
Chords
Slopes, etc
Weights and Measures
Milnc.
Pages.
Money Tables : Waojes, Interest
Values of gold and silver in £^ s.
and d
Properties of Materials
Land Surveying
Mine- <«
Traverse Table
Magnetic Survey
Heat, Sound and Pneumatics
Magnetism and Electricity
Hydrostatics
Hydraulics
Mechanics
Motive Power
Power Transmission
Geology: Coal
British Rocks
Mineralogy
M ineral Deposits
Classification of Deposit':
Coil A ' I I 1^^ -
Metal Lock. Power.' *V*^"'
Miners.
vale.
Pages. Pages. Pages. Pages.
lO ... ; 3
4
4
Dron.
I Pagts.
I6
I6 '
6 places.
43
7 places.
45
6 places.
4
3
(of Coal)
3
I
14
3 ! Hyp'r-
5 places, bolic.
. ' / 2 • • •
3 places.
14
16
15 I 13
90 ! 44
2 places. 6 place".
'^ dcg. 2 mio.
2 ; ...
II
SecElec
in Coal
Mining.
A% ...
8 ! 51
5 I ••
14 ' 10
\% I 39
3
2
10
38
18
5
3
I
18
3
6
28
18
2»
ZYz
1/
3
i7/'2
2 n
10
15 Stutis-
Gcneral tical.
26
Measur-
ing coal.
13
Sc Itch
Coals.
BOOK REVIEWS.
8i
SUBJSCT.
/
Coal ft
Milne. Metal
Miners.
Classification of Coals
Lodes and Veins 23
Beds and Layers 7
Irregular Deposits 4
Location of Faults 4
Prospecting ^
I
Boring 12^
Breaking Ground I 6
Rock-Drills
Air- Compressors
Explosives
Systems of Working : Coal Mining...
Metal Mining..
Sha^
Levels
Haulage I • i
Hoisting 17
Pages, . Pages.
! 4
Lock. Power.
Pages. Pages.
8
7
See
Pros-
pecting,
4
8
II
8
5
Pumping loy^
Ventilation 42
Mine-Gases I 10
Illumination of Mines 3
i
Coal-Cutting S%
I
Electricity in Coal-Mining
I
Coal- Washing
Crushing and Ore- Dressing 57
Metallurgical Processes 8
Gold-Milling
Mill Machinery 12
I
Hydraulic Mining j 1%,
River Mining
I
Copper Smelting
Roasting Pyrites
I
I
72
8
5
20
4K ,
i
5 ;
I
16
36
3
Sec
Hoist'g.
28
5
3
11'/
7
10
I
13
18
14
3
2
8
3
Meri-
vale.
Pages.
20
, Under
I Crush'gl
i&Orc-dr
4
6
5
3K
6
10
Dron.
Pages.
Under
Chem.
4
3
12
2
VOL. XV.— 6
82
THE QUARTERLY.
SUBJBCT.
Alloys, etc
Assaying and Chemistry
Valuing Metals and Ores
Mechanical Drawing
Geological Maps
Photography
Toxicology
Treatment of Injured Persons
Outline of Course of Mining Study...
Problems
Bibliography of Mining
Glossary
Index
Total No. of pages in Book
Number of Illustrations
Milne.
Coal&
Metal
Miners.
Lock.
Power.
Piigts, • Pages.
12
14
9
I »93
Pages. Pages.
6
22
I
472
58
Z%
4
4
46
12
334
II
Men-
vale.
Pages.
(>yi
Dron.
Pages.
42 ,Chem.of; Gases &
Gases.
aH
'57
Explos.
3
62
R. p., Jr.
BULLETIN OF ALUMNI AND COLLEGE NEWS.
Department of Mining.
The Summer School of Practical Mining was held this year in New
Jersey and Pennsylvania with a week at the World's Fair. In New Jer-
sey two weeks were spent at the Mount Hope mines of the Lackawanna
Iron and Steel Company. This was followed by a week of geological
field work under Professor Kemp in the vicinity of Franklin. Then
two weeks were spent in the new mines of Coxe Brothers & Co., at
Oneida, Pa. Finally a week was devoted to the study of the mining
exhibits at Chicago.
The Summer School this year was under the charge of Adjunct Pro-
fessor Peele, assisted by Edward B. Durham, E. M., '92 and Edward L.
Dufourcq, E.M., '92.
Mr. £. B. Durham, E.M., '92, lately assistant mining engineer for
Witherbee, Sherman & Co., and the Port Henry Iron Ore Company,
at Mineville, New York, has been appointed assistant in mining for the
An interesting lecture on the Shaw Gas Testing Machine, for the de-
termination of minute percentages of fire-damp, was delivered to the
students of the Summer School at Chicago, by Mr. Jos. R. Wilson. In
the audience were a number of distinguished mining men, including Dr.
Le Neve Foster, the recently appointed Professor of Mining in the Royal
School of Mines, London.
Through the liberality of a friend of the School a Shaw Gas Tester
has been purchased for the use of the Mining Department, and will be
used to illustrate the lectures on fire-damp and other mineigases.
The directors of the St. Joseph Lead Company, at Bonne Terre, Mis-
souri, have presented a beautiful model of their lead dressing works to
the Mining Department. This model was a prominent feature in the
Missouri State exhibit in the Mines Building at Chicago.
The exhibit of the Cleveland Iron Company consisting of large sec-
tional models of two of their mines near Ishpeming, specimens of ore,
mine timbers and photographs, has been purchased for the department.
These exhibits, the model of the St. Joseph Dressing Works and the
Shaw Gas Tester are valued at nearly $6000, and will prove very valuable additions to the Mining Museum. Department of Physics. In the Department of Physics considerable progress has been made in the various courses given ; besides this, a tutor and an assistant have been added to the corps of instructors, which now numbers nine. The in- struction of 170 students, working in sets, from 9.30 a.m. to 5.30 p.m. in the laboratory, and the delivery of several distinct courses of lectures to 250 students, and the reading of their examination papers, fully occu- pies the time of even so large a staff. The laboratory work being fully systematized, each student is furnished with a list of the experiments to be performed by him. There are nine such special lists. The course in Electrical Engineering occupies eight hours per week in 84 THE QUARTERLY. the laboratory throughout the year ; the other courses require from two to^ six hours per week during the entire year. This arrangement brings the geologists into the laboratory, and gives the chemists two terms' work instead of one. The laboratory instruction to electrical engineers has been increased from 6 to 8 hours per week, and the course of lectures on mechanical and electrical units has been extended for them through the second term of second year. These lectures on units formerly given also to students in other courses in the first term of third year, are now given in the first term of second year for all courses except architecture. The laboratory work of these students is also transferred from the third to the second year. Some forty new experiments have been added to the list, and others are ready as soon as apparatus and space are available. As it now stands, the list includes, under "length," all the usual measurements and tests with dividing engines, comparators, cathetome- ters, calipers, spherometer, optical lever, goniometer, sextant, planimeter level-tester, etc. The experiments on " mass," include all the methods of weghingand corrections therefor ; also specific gravity, vapor-density and molecular weights, and calibrations. As practice in " time measurements," students determine time of oscillation by various methods, length of seconds pendulum, etc. Work on resultant of forces, elasticity, inertia, capillarity, viscosity, and hygrometry serves to illustrate mechanical and molecular forces. Several measurements, including those on the velocity of sound, serve to illustrate the laws and apparatus of acoustics. In heat, the subject of thermometry is fully developed, as also specific and latent heat, boiling and melting points, expansion and radiation. A large list of experiments in optics, includes work on focal-lengths of lenses and^mirrors, construction and power of microscopes, telescopes, etc., the spectrometer, refraction, dispersion, wave-length, spectrum an- alysis, absorption spectra, polarized light, saccharimetry, total reflection, photometry and colorimetry. The course in electricity and magnetism offers determinations of magnetic moments and fields, distribution of magnetism, lines of force, etc. Resistance measurements are made by all the various methods, and with a great variety of apparatus. The practice of fall of potential and its applications are very fully illustrated and demonstrated. Specific resistance, insulation, electro-motive force, quantity, capacity, current, etc., are determined by methods designed to show the use and principle of the different forms of bridges, galvanom- eters, electrometers, rheostats, and commercial motors in general. Personal instruction is furnished to several post-graduate students, who are at present engaged in original research. Department of Mechanics. The Department of Mechanics as at present organized is represented in the faculties of the School of Arts, the School of Mines and the School of Pure Science. The officers of the Department are, R. S. Woodward. C.E., Ph.D., Professor of Mechanics; M. I. Pupin, Ph.D., Adjunct Professor of Mechanics, and Joseph Pfister, M.A., Instructor in Mechanics. The subjects specially assigned to the Department are pure mechanics, the principles of hydromechanics and thermodynamics. BULLETIN OF ALUMNI AND COLLEGE NEWS. 85 In the School of Arts, instruction in elementary mechanics is given by Professor Woodward and Mr. Pfister. Loney's Elements of Statics and Dynamics is used as a text, and this is supplemented by lectures and demonstrations with apparatus. In the School of Mines, instruction in anal3rtical mechanics is given by Professor Woodward. Parts I., III. and V. of Rankine's Applied Mechanics^ are used as a text. This work is supplemented by lectures, <lemonstrations and solutions of typical problems. Instruction in thermodynamics is given by Professor Pupin by means of lectures. Professor Pupin gives instruction also in theo- retical electrical engineering, in the third and fourth years of the course in Electrical Engineering, by means of lectures and recitations. In. the School of Pure Science, a course of lectures on the Theory of the Potential Function, by Professor Woodward, and a course on the Mechanical Theory of Electricity and Magnetism, by Professor Pupin, were begun with the present college year. In addition to these courses, which will be given annually by the Department, courses in higher Dy- namics, advanced Hydromechanics, Geodynamics, advanced Thermo- dynamics and its applications to electricity and chemistry, and the Elec- tromagnetic Theory of Light, will be offered for next year. Department of Metallurgy. A lathe for making sections of slags and steel is nearing completion. It is to be used for making the sections necessary for the continuance of the investigations on these subjects, which the department has now ander way. The collections of lecture diagrams, lantern slides, negatives and blue prints are being extended so as to include the latest data of modern metallurgical methods, and special sets of blue prints are in preparation for student use. Dr. Low and Mr. C. Vanderbilt have presented Mahler's bomb calor- iraetric apparatus, allowing work at a pressure of 175 atmospheres, and a digester, allowing work at a pressure of 75 atmospheres. A regenerative gas-furnace for high temperature work, and an oil-tank furnace for working at the temperature of boiling oil have also been obtained. Mr. E. L. Kurtz, '93, has sent the department two fine specimens of salamanders, taken from the hearth of a blast-furnace after going out of blast. These salamanders of crystallized iron weigh nearly 40 pounds each. A good specimen of nitro-cyanide of titanium was also obtained. MiNERALOGICAL DEPARTMENT. The Faculty decided, at their last meeting in the spring, that lithol- ogy should hereafter be taught to all students in the courses of mining, chemistry, geology, and metallurgy, and, to make the necessary time, the work in mineralogy was transferred from the second year to the second term of the first year and first term of the second year by giving the De- partment of Mineralogy extra hours in the first year. The time thus secured in the second term in the second year was assigned to the subject of lithology under the Departments of Mineralogy and Geology. The work in lithology under the Mineralogical Department will be in charge of Mr. Luquer, tutor in mineralogy, and will consist in : A short introductory review of the principles of optics relating to reflection, refraction, and polarization of light. A description of common appar- 86 THE QUARTERLY. atus used, such as the lithological microscope, the polariscope, the ap- paratus for measuring axial angles, dispersion, indices of refraction, etc. A description of the common optical character of the rock-forming min- erals, with methods of recognizing and distinguishing said minerals. Mr. Luquer is now arranging in a new and convenient form the data for recognizing optically the different minerals occurring in building-stones and also the economic effect of the minerals on the stones. In connec- tion with this a series of comparative tests on building-stones, between the artificial sulphate-of-soda freezing and actual freezing, are being made ; and a complete bibliography of the literature on building-stones is also in course of preparation. The collections of the mineralogical museum are being supplemented by two more special collections. The museum now contains, in addi- tion to the main collection, the following collections especially designed for facilitating instruction : Collection of pseudomorphs ; collection illustrating physical characters ; collection illustrating association of minerals ; collection of minerals of building-stones for civil engineer and arch students. Two student collections of different grades. To these there have been added collection of minerals of New York City and collection of natural crystals. The former has for its nucleus the specimens donated by Dr. J. J. Friedrich, and supplemented by speci- mens selected from the general collection. The crystal collection is designed not so much as an exhibit of beautiful crystals, but as an aid to comprehension of the science. The plan followed in it is as follows : Crystals of isometric minerals are ar- ranged, as there is only one series of forms, by forms and not by min- erals. In all other systems, as each mineral has its own series of forms, involving distinct axis-ratios, the arrangement under each system is by minerals, and each mineral is preceded by a wooden model of the ac- cepted unit-form, and this followed by as many forms as are obtainable. Mr. Ries, University Fellow in Mineralogy, has taken for his work, investigation of the pyroxene group, with especial reference to these pyroxenes occurring in New York State. This includes : An examina- tion of the optical properties and chemical composion ; the mode of occurrence of the pyroxenes, their relations to associated minerals as well as their order and manner of formation ; also crystallographic mea- surements to determine the association of forms occurring in the New York specimens. The department has purchased a No. 2 Fuess reflection goniometer with all accessories for crystallographic work. A Bert rand refractometer has also been secured. This instrument is of very small size (can be carried in the pocket), and gives, with very close approximation, the indices of refraction of liquids and solids — needing, with solids, simply a polished surface. During the past summer Mr. Luquer's work in cutting sections of building-stone was so facilitated by running the section grinders with an electric motor, that this fall three electric motors have been secured, so that all the grinding and cutting machines may be run by electricity. This department acknowledges the following donations : From E. Cumenge, specimens of gold in fluorite, boleite, cumengeite, phosgenite. From Dr. J. J. Friederich, a collection of New York City minerals. From M. Fran^illon, specimens of garnierite. BULLETIN OF ALUMNI AND COLLEGE NEWS. 87 Geological Department. Mr. C. A. HoUick, who has been for two years assistant in Geology, was promoted to be tutor last spring. The vacant assistantship was filled by the appointment of Mr. Gilbert Van Ingen, who has studied at Cor- nell and Yale, and done much collecting for the U. S. Geological Sur- vey. Mr. Van Ingen will be employed in arranging and sorting the collections of fossils in the museum^ which have been in great confusion. The way is being prepared for systematic and complete instruction in palaeontology in the future. Professor Kemp spent June and September in field-work in the Adirondacks, being accompanied in the former by Matthew and Pomeroy, '93, White, '94, and Riederer, '96. Professor C. H. Smyth, Jr., ^%%y now of Hamilton College, also joined the party for a time. In September, Ries, '92, was with Professor Kemp. Efforts were directed toward mapping the geology of the Adirondacks, and will be continued next summer. Professor Kemp spent a week with the summer class in mining, exploring the geology of Franklin Furnace, N. J., and vicinity ; some twenty students formed the party. Mr. Hol- lick was engaged throughout July in further work upon the Cretaceous exposures and the eastward extension of the Yellow Gravel formation on the north shore of Long Island, and on Martha's Vineyard. Some interesting discoveries of fossil plants and moUusks resulted. W. D. Matthew, '93, is Fellow in Geology, and is working on the igneous rocks near his home, St. Johns, N. B. BroLOGicAL Department. During the past summer, twelve members and students of the de- partment worked in the Marine Biological laboratory at Wood's Holl, Mass. The College subscribes for one of the investigator's rooms at this laboratory. Mr. Willey worked upon the development of Molgula in connection with his researches upon the ancestors of the vertebrates. Dr. Dean continued his studies upon the embryonic development of the sturgeon, from material procured by artificial incubation at the sturgeon fisheries on the Delaware. This is the first time sturgeon culture has proved completely successful, and Dr. Dean's success will doubtless lead to the establishment of a sturgeon hatchery. Mr. Strong worked upon the cranial nerves of the fishes and amphibians. Professor Wilson con- tinued his studies upon the development of Nereis, He also made a reconnaissance of the Pacific coast, in order to advise the University of California regarding the location of a Marine Station. Professor Os- bom delivered the vice-presidential address before the Section of Z06I ogy of the American Association for the Advancement of Science, and later, joined the palaeotological expedition of the American Museum of Natural History in Southern Wyoming. The department opens the year with about the same number of un- dergraduate students as last year, but with a greatly increased graduate roll. The large undergraduate laboratory in the medical school has accordingly been turned into a graduate rooin. Besides the work of different members of the department in the Biological Section of the New York Academy of Sciences, a special Morphological Club has been formed for reports upon special researches, and upon recent important articles in the biological journals. 88 THE QUARTERLY. All of the university course of lectures are being given this year, and th6 department is, for the first time, in full running order. Department of Mechanical Engineering: The changes made in this department by virtue of the redistribution of the engineering subjects among the officers of instruction have been considerable. The subjects of motors using water, air, steam and other vapors ; heat, and its applications to the steam-engine, and the construc- tion and management of boilers and engines, make a compact and hom- ogeneous series of three courses of lectures for the head of the depart- ment to the graduating class ; and he retains his course in properties of materials for the third class for all engineering students. To provide for the work in the locomotive engine and on the transmission of power in machinery and millwork, displaced by these new assignments, Mr. Ira H. Woolson has been assigned to this department, and is lecturing to the graduating class in both courses, in addition 'o a responsible charge of the work in construction-drawing for the electrical engineers of the higher classes. He also runs the testing laboratory and the in- struction therein, and the detail of cement-testing forcivil engineers. Arrangements have also been made to have the engineering students of the third class do some testing of materials in the laboratory as part of the obligatory afternoon work of that year. It will involve tests in tensile, compressive and transverse resistance, and will be done mainly upon the reconstructed Fairbanks machine, which has been redesigned in iron and steel by the head of the department for this purpose. Mr. Luther E. Gregory of '93 has entered the department as assistant in this mechanical department. Considerable additions to the outfit in dynamometers have been made during the summer, and students are beginning to take theses involving laboratory investigations as facilities are provided. The work in first and second year drawing has been assigned to the department of mechanical engineering, where it most naturally seems to attach itself, and Mr. Mayer is in resix)nsible charge of it. The increase in the number of students and the hours of their service in the drawing- academy during all day made it necessary to apply for an additional assistant in this department, both for efficiency and as a relief to over- work. Mr. F. A. Provot, C. E. of '93, has been appointed assistant in drawing to fill this position. Mr. Gregory conducts the laboratory work with the indicators. Electrical Engineering Department : Mr. George F. Leon, who received his scientific education at the Massachusetts Institute of Technology, and who has had six years' prac- tical experience in electric railway, lighting, etc., with the Thomson- Houston Company, has been appointed instructor in electrical engineer- ing. Mr. Leon will take special charge of the laboratory work in the actual testing and use of dynamos, motors, and other electrical machin- ery. The total number of students now pursuing the course in elec- trical engineering is about one hundred, including about twelve post- graduate students. The regular four-year under-graduate course, as well as the post-graduate work, is now well organized. Vol. XV. No. 2. JANUARY, 1894. THE SCHOOL OF MINES QUARTERLY. A jrOlTRNAI. OF APPI.IHD SCIBNCB. «•> BOARD OF EDITORS. A.J. MOSBS, Adj. Prof, of Mineralogy. E. WALLER, Analytical Chemist. J. P. KEMP, Prof, of Geology. J. L. GREENLEAP, Adj. Prof. Civil Engineer'^. R. FERINE, Jr., Adj. Prof, Mining. JOS. STRUTHERS, Tutor in Metallurgy. Managing Editor, A. J. MOSES. CONTENTS: Details of Modern Water Works Construction. By Wolcott C. Foster, 89 Acantliite from Colorado. By Albert H. Chester 103 Curdling of Milk. By Malvern W. lies 105 A Plant for Granulating Slag. By Richard H. Terhune, E.M 108 A Relation of Engineering to Progress and Civilization. By F. R. Hutton, C.E., Ph.D no Present Condition of the Mechanical Preparation of Ores in Saxony, Hartz and Rhenish Prussia. By M. Maurice Bellom Z15 A Prencb Regenerative Gas Furnace. By Joseph Struthers 138 Professional Notes 143 Abstracts ^47 Book Reviews 158 Index to Mineralogical Literature. By A.J. Moses and L. McI. Luquer, 163 Bulletin of Alumni and College News 180 COLUMBIA COLLEGE. NEW YORK CITY. Registered at the New York Post Office as Second Class Matter. TTVO DOLLARS PER YEAR. FIFTY CENTS PER NUMBER. All Remittances should be made payable to Order of '*The School of Mines Quarterly." ^af KeariTcy.;& loot . Com WOHKS, PATBH80H, NEW JBBBSir. Office, 100 and 102 Reade Street, New York. MANUFACTURERS OP FILES AND RASPS^ OF SUPEBIOa QUALZXT. We make Capacity aUALITY of plant and 1350 DOZEN FINE WOBE- a day. MANSHIP our first nitutr^Md CaUloga mtilti OIL TMeipt of consideration. States de MnU poiUg*. aling in Hardware Leading houses throughout the United or Machinists Supplies cany our Files instoc^ JSNKIHS BROS., Jenkins' Bros. Valves and Jenkins' Standard Packing. HEWTOBE, BOSTON, CHICAOO, PHILADELPHIA. THE SCHOOL OF MINES QUARTERLY. XV. JANUARY, 1894. DETAILS OF MODERN WATER WORKS CO> STRUCTION.* Bv WOLCOTT C. FOSTER. Pakt I. — Cast-Iron Bell and Spigot Pipe; Special iNGS ; Flejcible Joints. At the present day cast-iron pipe is undoubtedly the be most economical form of pipe for use in general water work: struction. Special cases and surroundings will, however, times require other kinds of pipe. For water works pu the pipe should always be coated. The coating usually emj is one of the tar or asphalt mixtures. There are two ki cast-iron pipe in use; Bell and spigot pipe. Fig. 1, and pipe. Of the latter we will treat later on. In speaking of the size of pipe of any kind the clear diameter is always mentioned; thus four inch-pipe meat having a clear diameter inside of four inches. Bell and Spigot Pipe. This pipe is so named on account of the shape of tht The enlarged end is called the bell or hub and the bead< the spigot. For each diameter of pipe the manufacturer out different thicknesses and consequently weights depi upon the service required and the pressure. In table.s are the weights per foot and per length :or different sizes, as by one of the prominent companies dealing in cast-iron pip " Copyriglil, 1894, by Wolcott C. Foster. 90 THE QUARTERLY. Table I. Weights of Cast' Iron Pipe^ zuith Allowance added for Bowl and Spigot Ends, (Weights in Columns, per lineal foot.) a si be C 3 4 '5 6 8 lO 12 14 i6 i8 20 24 30 35 U % 4 5 [6.5 8 10 14 15 18 20 22 26 32 40 45 9 ' >3 II ' 17 I ^■5 21 16.5 25 21.5 32.5 27 ' 40.5 32 48 37 41 47 52.5 63 36; 47 56 64 72 79 95 78 118 90 i 13s 94 I 141 Thickness of Iron Shell in Inch us. ^% x>i 1% ^}4 135 «37 I 172 177 ! 198 176 201 ' 224 250 275 330 405 450 483 276 335 ; 384 433 305 ! 336 I 364 398 449 ; 493 I 495 540 533 583 >^ 2 398 470 577 668 686 458 543 664 766 788 Standard Weights of this Foundry. Diameter. Approximate Weight Weight Inches. 3 Thickness of Shell. _ per foot. »5 per length. 180 3 K 17 204 4 'A 22 264 6 % ZZ 396 8 'A 45 540 10 9 60 720 12 A 75 900 12 H 80 960 14 U "7 1404 16 M 125 1500 18 % 167 2004 20 n 200 2400 24 1 250 3000 30 ^% 350 4200 36 •A 475 5700 MODERN WATER WORKS CONSTRUCTION. 91 Table II. iToposed American Association Standard for Cast- Iron Water Pipe. Size. Inches diameier. 4. 8. 10. 12. 16. 20. 24. 30. 36. 48. 1 E . .2 S 1 M Clx<» V s ■0 — a ii (3« A B C I A U C A ! B C 1 A B ; c i A , B C A B C I A B C I I A B A ' B I C A B C A B C V o e < c 3.856 .428 4.904 452 7 000 .500 9.094 .547 1 1 11.190 •595 13286 .643 1 t 17.476 .738 21.666 .833 i 25 856 , .928 32.142 1 1. 07 1 38.428 1. 214 51.000 • 1.500 Q. • ^ - a 14,000 15,580 17,170 19,170 21,330 23,500 31.330 34,830 38,330 44,750 49.750 54,750 60,570 67.330 74,080 78,250 86.920 95.580 119,170 132,420 145,580 "65,330 "83,750 202,080 220,750 245,250 269,750 316,250 351*420 386,580 42^,750 476,420 524,080 710,670 789,670 868,670 Weight pkr Length, (12 ft. 4 in.) ^ Including Bell. Average. I Max. 168 187 206 230 256 282 376 418 460 537 597 657 727 808 889 939 1,043 ",'47 ',430 1.589 1,747 1,984 2,205 2,425 2,649 2,943 3.237 3.795 4,217 4,639 4,145 5,717 6,289 8,528 9.476 10,945 178 196 216 243 267 296 395 439 483 567 627 690 768 848 933 991 1,095 1,204 i,5«o 1,668 1,834 2,195 2.3 "5 2,546 2.796 3.090 3,398 4,006 4,428 4,871 5,43 « 6,063 6,603 9002 9.950 "0,945 Min. 160 "78 1^6 218 243 267 357 397 439 510 567 627 691 768 848 892 99" ",095 ',359 1,510 1,668 1,885 2,195 2,3"5 2,5"7 2,796 3.090 3,605 4,006 4,428 4,888 5.43" 6,003 8,102 9,002 9,950 Table II. gives the weight of pipe for different services, as pro- 92 THE QUARTERLY. I posed at the meeting of the American Water Works Associa- tion, at Chicago, May 20, 1890. Fig. I. Bell and Spigot Pipe. The quoted weights of pipes of the same diameter and for similar services vary with each foundry, but usually approximate the weights of Table I., very closely. Some makers quote the weight per foot without making an allowance for the extra weight of the bell and spigot, hence in drawing specifications and in purchasing pipe special attention should be paid to this matter. It is usually better to specify the weight per length rather than per foot and thus avoid controversy and a possible claim of misunderstanding. A variation of 5 per cent, for 3 -inch to 24-inch and 3 per cent, for 24-inch to 48-inch pipe above or below the contract weight is generally allowed. Each length is considered by itself; those lengths falling below the minimum are rejected while for those heavier than the maxi- mum the excess is deducted and not paid for. The number of lengths below the average weight should be about equal to the number in excess so that the total shipment will not vary more than I per cent, or 2 percent, at the most from the average weight of the specifications. Pipe up to 48 inches diameter is usually submitted to a hydraulic test of 300 pounds per square inch before shipment. Some few foundries make pipe up to 144 inches diameter. The weight is marked with white lead inside the bell, and con- secutive numbers either painted or cast upon the outside of the pipe near the bell. In addition to these marks the initials of the water company or town and the year are frequently cast upon the outside, together with the initials of the maker. This is especially the case with large orders. When a large amount of pipe is purchased it is well to have a competent inspector at the foundry. This will usually save considerable expense and trouble. With small orders, however, this precaution is not so material. Very satisfactory results in this respect and at a minimum ex- MODERN WATER WORKS CONSTRUCTION. 93 < S u es o 1 0; ^ ^ ^ Deduction. i : ro : i : : ! i sg 5 Length Weight. 0«0»n»n00*n00 Ml 5; Length Numbers. o\ Diameter Inches. 00 :::::::: : • *JIO331SJia03 2ttiX«f-9<Iid o] c 0S (S Q;2 M y h M* V 3 PS t** ::::*••• : t«N. N :::::::: : N »'>::::::•:: *r\ ir» ..:::::: : u^ 8 8 NO • • ^ :::::::: : • »5 :::::::: : rt 4^ Q^ H z -a o 4> 61A s 01 (A u o • MM o «^ o e (A 94 THE QUARTERLY, pense can usually be obtained by placing the foundry inspection in the hands of some reliable inspection association but care must be used to obtain, not the cheapest inspection, but ** inspection that insp)ects." After the pipe has arrived at its destination, an inspector should look it over as it is being unloaded from the cars, watching care- fully for breakages and cracks in both spigot-and bell-ends, at which points injury or defects most usually occur. It sometimes happens that the ends are cracked by the shifting of the pipes in the cars and their striking against each other. At the same time the number and weight of each length should be noted, together with the other data called for in the following heading for the in- spector's note-book : The iron should be soft, easily bored and cut, and the castings should be smooth and free from all defects, such as sponj^iness, lumps, swells, blisters, sand-holes, blow-holes, and the like, and should be of even thickness throughout. There is as yet no uni- versal standard practice in relation to cast-iron pipe, but the above remarks are based on considerable experience. A set of pipe specifications which are fair to both contractor and purchaser, and which will secure good results, will be given later. Straight pipe from 4 inches in diameter up is cast to lay 12 feet to the length, though as turned out by some makers it will be found to lay somewhat more. Anything other than straight bell and spigot pipe is called a ** special " or special casting. Specials include bends or curves, tees, crosses, Y's, plugs, sleeves, reducer*?, caps, etc. There are two prominent classes of bell and spigot specials, namely, ordinary specials, such as those shown in Figs. 2 to 1 1, and "Globe" specials, shown in Figs. 12 and 13. Globe specials are claimed to be lighter, more compact, and to give greater waterway than ordinary specials nnd are being used very extensively. Either class are made with bells all around, with spigots all around, or with bells on some ends and spigots on others. In making out a bill for ordering special castings, the safest way to designate tees, crosses, Y's, reducers, etc., is to draw a skeleton diagram and indicate on which ends the bells are wanted by a short curve, placing the diameter opposite each end, as shown in Fig. 14. Curves can be made of any radius desired, but the foundries usually have patterns made up of moderate radius, the length of the radius varying with the diameter of the MODERN WATER WORKS CONSTRUCTION. 95 pipe. They are spoken of as elbows (90^) or one-quarter bends (Fig, 2a), one-eighth or 45° bends (Fig. 2b), and one-sixteenth Fig. 2a, U L J Short Elbow. Elbows or 90° Bend. Curved Pipe, or 223^° bends (Fig. 2^), according to the angle they subtend. Globe elbows are made of any angle. Ordinary curves can, of course, be made to subtend any angle; but patterns have to be Fig. 2b. I r— -i»--"! One-eighth, or 45° Bend. altered or new ones made unless the foundry happens to have made a similar bend before and has the pattern on hand. Where 95 THE QUARTERLY, long radius curves or specials cast on the arc of a circle are used, odd angles can be made by cutting off a portion of the spigot- end. Long radius bends have, theoretically, a slight advantage Fig. 2f. W F-j ^ One-sixteenth, or 22^ Bend. over the kind illustrated, as the change in the direction of the current of water is more gradual ; but the benefits actually de- rived in use seldom pay for their increased cost. Fig. 3. Fig. 4. Fig. 5. Tee. Y. Cross. Tees are three-way special castings, two of the branches being in a straight line and the third one at right angles, Fig. 3. Y's are three-way special castings in which the branches are inclined to each other at angles other than right angles, Fig. 4. Unless otherwise specified, Y's are sent with two of the branches MODERN WATER WORKS CONSTRUCTION. ^-j in a straight line and the third branch leading ofT at an angle of 45°. Crosses are four-way special castings, Fig. 5, Reducers are straight special castings, each end of which is of different diameter, Fig. 6. Sleeves are special castings for joining together two spigots or plain ends of pipe. Fig. Ta. Halved or split sleeves are sleei/es made in two parts to be placed over the jwpe and bolted together, Fig. yb. rialved or Split Sleeve Plugs are special castings used to stop up open ends of the pipe or special castings. Fig. 8. FiO. S. D a 98 THE QUARTERLY. Caps are special castings used to place over open spigot-ends, Fig. 9. S-bends or ofTsets are used to connect two lines of pipe which run in the same direction but which will not abut on being brought together, Fig, 10. D Cap. Offset. \\m FlanEC, Hat flanges are used to connect a new line of pipe with an old line already laid where provision by the insertion of a tee or other special has not been made, and where it is not desirable or economical to insert one. Fig. 1 1. There are other forms of special castings, but the above embrace those most commonly in use. Where a special, such as a tee, is to be inserted in an old line of pipe, there are two ways of doing it open to the choice of the MODERN WATER WORKS CONSTRVCTJON. 99 engineer. The first or old-fashioned method is to cut out a piece of pipe, say three or four feet longer than the special to be in- Odd Shaped or Combination Globe Special. serted, and then cut offa piece of pipe somewhat shorter than the length of pipe cut out less the laid length of the special. A sleeve A 7i^ Method of Uetining Specials. is slipped over one of the etids of the length of pipe, the short piece connected with the special, and the two slipped into place; lOO THE QUARTERLY, the sleeve is then pushed over the two spigot-ends, so as to give an equal length on each side of the joint, and the joints made up. Fig. 15. Or a special having a spigot-end may be used instead of using the short piece of pipe and the joint made up with a sleeve, Fig. 16 ; or the two opposite ends of the special may have spigots and two sleeves used, Fig. 17. Fig. 15. ._j I Method of Inserting Tee, KiG. 16. Method of Inserting Tee. Fig. 17. I I Method of Inserting Tee. The second method is by using what is called a " cutting -in " or " Dunham '* special. This is a recently invented contrivance, and has been on the market but a short time, Fig. 18. The pecu- liarity about it is the shape of one of the bells. A piece is cut out of the pipe of the proper length ; the special is held at an angle, and the special bell slipped over one of the ends of the pipe until the opposite bell passes the other free end of the pipe. The special is then dropped into line with the pipe, and pulled back until the pipe abuts against the bottom of the ordinary bell. The joints are then made up. MODERN WATER WORKS CONSTRUCTION. loi Specials are not subjected to the hydraulic test by which pipe is examined, but should be carefully inspected. Special pains should be taken in inspecting at the junction of the bell with the body, and at the places where the supply of metal enters the mould. There small hemispherical lumps often appear. These spots are likely to have blow-holes running clear through the castings. Fig. 1 8. •*Cutling-in" or "Dunham" Special. Boring out these holes in either straight pipe or specials, and fill- ing them up with a rivet, as is frequently done, should not be allowed, nor should the foundries be allowed to calk up the holes by hammering over the surrounding metal. In all pipe and specials care should be taken to see that the pipe " chambers " — that is, that the spigot end will enter the hub or bell end to its full depth. There is no universal standard of shape or dimensions for either bell or spigot. The variety of bell Fig. 19. Bells. designs seems to be without end. (Fig. 19 shows a few.) Bells less than 3^ inches deep should never be used even on the smaller sizes of pipe. With shallow bells it is difficult to get either a good or a tight joint, and the joints are easily sprung. Neither can curves of long radius be made by " pinching " joints if the bells are shallow. The matter of being able to lay straight pipe around curves is frequently a very useful factor, saving the extra cost of specials. Eight-inch pipe, with good bells, can eas- 102 THE QUARTERLY. ily be laid on a io° curve by " taking it out of the joiits " without cutting. Where the lead room is large, or where the pieces or short curves of much greater degree can be laid with straight pipe. An excessive amount of lead room is of no benefit, and contributes to a waste of lead, which is costly, A moderate amount of lead room, say about three-eighihs of an inch between the outside of the pipe and the inside of the bell answers every purpose. The inside of the b^ll should have a groove of moder- ate dimension around it, near the outer end. Where different weights of pipe of the same diameter are to be joined together, and the pipe will not chamber, a sleeve can be used. If it is de- sired to have the bells face one way, then the bell end of the proper length should be cut off, just back of the bell, so that the sleeve may fit over the pipe. In cases of emergency sleeves may be made from pieces of pipe ot the next highest diameter, but, as a rule, such sleeves should only be resorted to when it is not possible to wait for or obtain regular sleeves. Fkwble Joints. In designing work it is, of course, more economical in both time and money to use, wherever possible, standard or stock pattern specials. When patterns have to be altered, or new ones made, the castings are not cnly more costly, but considerable delay is apt to result. At times, however, by using an odd special, one casting can be made to take the place of several, and then it is frequently economy to require such a casting. Flexible joints (Fig. 20) are used in laying pipe underwater. They are built upon the ball-and-socket principle, and there are several different designs upon the market. In closing, it may be well to state that ordinary straight pipe is sold by the ton of 2240 pounds (sometimes the ton of 2000 pounds ACANTHITE FROM COLORADO. 103 « is quoted); ordinary special castings by the pound; globe and other patented specials by the piece. The price of pipe varies from$20 to $35 per ton delivered f. o. b., cars or boat at destina- tion, depending on the diameter of the pipes, state of business, size of order, and place of delivery. In the immediate vicinity of New York the smaller sizes cost from$27 to $29, and the larger$2^ to §27 per ton. Ordinary stock-pattern specials, two to three
cents per pound, usually about two and a half cents. Specials
for which patterns have to be made, two and a half to five cents a
pound.
By albert H. CHESTER.
An examination of some crystals of silver sulphide from the
Enterprise Mine, at Rico, Colorado, seems to justify the opinion
that they belong to the rare species acanthite, heretofore found
only in a few localities in Saxony, and about the existence of
which as an independent species there has recently been some
question.
These crystals were found attached to only two specimens
among a large lot kindly sent to the author by Mr. D. Kirby,
superintendent of the mine.
It is iron- black in color, with a brilliant metallic lustre. Owing
to the small amount of material at hand, its .specific gravity was
not taken. The mineral is sectile, but le.ss so than argentite. It
cuts easily and will flatten under the hammer, but breaks quij:e
readily when bent suddenly. Chemically it is pure silver sul-
phide, containing 12.58 per cent, of sulphur and showing traces
only of iron and copper. A complete analysis has not been
made, owing to lack of material ; but no doubt is entertained
that it is silver sulphide, AggS, having the theoretical compo-
sition of sulphur, 12.9 per cent, and silver, 87.1 per cent.
The more perfect crystals are about 6 mm. in lengih and 0.5
mm. in thickness, and occasionally show distinct terminations of
the basal pinacoid. They are generally very deeply striated
lengthwise, and there are no distinct prismatic planes on which
I04 THE QUARTERLY.
measurements can be taken. The basal plane is apparently at
right angles to the long axis of the crystal. Many of the crys-
tals run out to acute terminations, but whether as domes or
pyramids cannot be definitely stated. The whole appearance,
however, is decidedly orthorhombic, resembling on a small
scale certain aggregations of goethite or manganite, where the
crystals are often grouped in bundles laid parallel to the long
axis of the prism. Sometimes the groups are in tabular aggrega-
tions, but always showing deep striations and presenting the ap-
pearance of small, corrugated plates.
Associated with the acanthite, and occurring in such quantities
as to form one of the most valuable minerals in the mine, are
small masses of silver sulphide,, called locally " nuggets." These
masses are usually rounded, as if they had been fused, and are
superficially coated with chalcopyrite, which takes a purplish tar-
nish on exposure to the air. Often this silver sulphide is found
filling cavities between quartz crystals, and consequently taking
angular shapes easily mistaken for crystals. Occasionally this
silver sulphide constitutes the matrix of the quartz crystals, serv-
ing to hold together a specimen that would otherwise fall apart ;
but in all cases it is coated as above mentioned, and some of the
specimens are of singular beauty in consequence. When this
coating is removed the mass is found to consist of pure silver sul-
phide, slightly harder and a little less sectile than argentite, of
which abundant specimens are found in the mine, both in crystals
that are distinctly isometric, and in masses, some of which weigh
several ounces. None of the crystals, however, have the coating
of copper pyrites. From these physical differences it is suggested
that the ** nuggets " may be massive acanthite rather than argen-
tite.
Associated with the acanthite and argentite are stephanite, poly-
basite, tetrahedrite, and pyrargyrite, with sphalerite, chalcopyrite,
and pyrite, all set in bright pink rhodochrosite.
Rutgers College, New Brunswick, N. J.,
December 22, 1893.
CURDLING OF MILK. 105
CURDLING. OF MILK.
By MALVERN W. ILES.
In 1877 the writer made some very curious and interesting
observations upon the curdling of milk. These results were
embodied in an article written for the ^o^ton Journal of Chem-
istry, Vol. XII., No. 6.
thunder-storms;" and in consideration of the fact that mere chance
has caused me to still further add to the literature on this subject
by some laboratory tests, I therefore deem it expedient to bring
before the readers of the Quarterly the results obtained in 1877.
The article in question says :
'* There have been various surmises in regard to this subject ;
none, so far as I have been able to learn, have been substantiated
by experiments.
" In order to learn whether milk did really sour during heavy
rain and thunder-storms, I made several observations which proved
to me that this opinion, so commonly held by the dairymen, was
not erroneous. My experiments to arrive at the cause of the
phenomena thus observed may be stated as follows :
" I took skimmed morning's milk, filled an eudiometer tube
(3CX3 ex.), and introduced 100 c.c. pure oxygen gas; then by
the use of an ordinary' battery and a small Ruhmkorfif coil, sparks
of electricity were made to pass through the oxygen fjr five min-
utes. The current was then broken, and the tube shaken up and
allowed to stand for five minutes. The milk does not appear
quite as opaque, and shows a noticeable acid reaction. On con-
tinuing the current for five minutes longer, making ten minutes
in all, the milk curdles very perceptibly, and shows a decided
acid reaction. The contents of the tube on standing for twenty
minutes had reached the consistency of ordinary sour milk or
* bonny-clabber.'
*• From the above experiments it will be seen that oxygen was
converted into ozone, which we think may be stated as the cause
for the rapid souring of milk during thunder-storms.
VOL. XV. — 8
io6 THE QUARTERLY.
** The increased acidity is due to the formation of lactic acid,
and most probably some acetic acid, by means of the ozone.
One or both of these acids causes the casein to be precipitated."
By carefully reading the above extract it will be observed that
I was very careful not to venture an opinion or to generalize fur-
ther than I thought was entirely safe from the highly interesting
obsj^rvation.
Nothing further was done in regard to this subject by the writer
for sixteen years, until by chance the acquaintance of an old prac-
tical cheese manufacturer was formed. By insisting upon a very
careful statement of all details pertinent to the cheese industry,
the use of rennet was brought to my attention, and the thought of
the ozone experiment I made at the Johns Hopkins University
came back clearly to mind.
If ozone will cause a precipitation of casein, why will not per-
oxide of hydrogen do likewise ?
Upon my return to my home in Denver, I found by actual
laboratory test that peroxide of hydrogen does actually cause
the casein to separate not only easily but with perfect complete-
ness. The reaction is somewhat facilitated by gentle application
of heat, but this is not absolutely necessary. Other oxidizing
agents were then tried upon perfectly pure, sweet milk, and I
found that bromine-water causes the same curding of milk; also
many other oxidizing agents will do likewise. I tried also per-
manganate of potash and bichromate of potash solutions, and they
also acted as curding agents ; particularly by gentle warming is
the reaction facilitated.
W)iile it is well known that many of the mineral acids pre-
cipitate casein from milk, and that the cheese manufacturer uses
a portion of a calf's stomach called rennet, or lately a prepared
solution of rennet ; yet we also now learn that many other agents
will act in a similar way as ozone, peroxide of hydrogen, bromine
water, permanganate of potash, and bichromate of potash.
While the above last named agents are all powerful oxidizing
agents, yet it cannot be safely concluded that the mysterious
chemical action of rennet, is also oxidizing in its action, still it
fortifies us with a fact which will possibly aid towards the clear-
ing up of a thing which has always puzzled the wisest philoso-
phers. I suggest and propose to use peroxide of hydrogen as a
CURDLING OF MILK. 107
substitute for rennet in the manufacture of cheese in the future.
It will be readily seen that nothing of a harmful or injurious
nature will be introduced into the cheese, but as an actual fact no
chemical or particle of matter will enter the cheese, used as a
precipitant of the casein, as the peroxide of hydrogen will simply
lose one atom of oxygen and be converted into water. In Blox-
am's Chemistry (2d edit.) page 600 and 601 we find the following :
'* When an acid is added to milk, the casein is separated in the
form of curd, in consequence of the neutralization of the soda
which retains it dissolved in fresh milk." Also that, " Coagu-
lated caseine may be dissolved by acetic or oxalic acid, but the
addition of sulphuric or hydrochloric acid reprecipitates it, these
acids apparently forming insoluble compounds with casein. It
is also stated by the same authority that : *' This action of rennet
upon milk has not yet received any satisfactory explanation. '*
In Dr. Justus Von Liebig's Familiar Letters on Chemistry as
edited by Dr. John Blyth, I have found an interesting treatment
on the casein of milk. It is there stated (page 225):
" The skin of animals, the mucous membrane of the stomach
and intestines, and the urinary bladder, have many properties in
common with gluten and yeast. In their fresh state these sub-
stances exercise not the slightest influence upon starch or milk
sugar, but when placed in water for a few hours, or even when
simply exposed to the atmosphere, they quickly pass into a state
of decomposition, which renders them capable of converting with
great rapidity starch into sugar and milk sugar into lactic acid.*'
This property of the mucous membrane of the stomach of the
calf has been made use of, from time immemorial, in the prepara-
tion of cheese, in order to make milk coagulate, or, in other
words, to effect a separation of the cheese from the other consti-
tuents of milk.
The solubility of cheese in milk is in consequence of the pres-
ence of alkaline phosphates and of free alkalies. In fresh milk
these substances may be easily detected by the property it pos-
sesses of restoring the blue color to reddened litmus-paper.
The addition of any acid, by neutralizing the alkali, causes
the cheese to separate in its naturally insoluble state. The acid
indispensable for the coagulation of milk is not added to the milk
in the preparation of cheese, but it is formed in the milk at the
expense of the milk-sugar present. A small quantity of water is
io8 THE QUARTERLY,
left in contact with a small piece of a calf's stomach for a few
hours or for a night ; the water takes up a quantity of the decom-
posed mucous membrane so minute as to be scarcely ponderable :
this, called rennet, is mixed with milk ; its state of transformation
is communicated (and this is here the most important circum-
stance) not to the cheese, but to the milk-sugar, the elements of
which transpose themselves into lactic acid, which neutralizes the
alkali, and thus causes the separation of the cheese. By means
of litmus-paper the process maybe followed and observed through
all its stages ; the alkaline reaction of the milk ceases as soon as
the coagulation begins. If cheese be not immediately separated
from the whey, the formation of lactic acid continues, the fluid
turns acid, and the cheese itself passes into a state of decompo-
sition."
In conclusion, I will state that I will not be able to pursue
this subject further, but hope others interested in scientific pur-
suits or the practical manufacture of cheese will be induced to
make further tests as a resultant of a few experiments I have
made, and under remarkably peculiar circumstances.
I need hardly add to the readers of the Quarterly that my
duties as a smelter of lead, silver and gold ores is not even re-
motely connected with a cheese factory. However, the cheese
man can use peroxide of hydrogen instead of rennet, if he so de-
sires, with my kind wishes.
The Globe Smelting and Refining Company, Denver, Colorado,
November 1 3, 1893.
A PLANT FOR GRANULATING SLAG.
By RICHARD H. TERHUNE, E.M.
The granulation of slag offers many advantages, among which are
the economic disposal of the material, reduced heat about the fur-
nace room and yard, and the production of thinner " shells " where
the system of tapping the pot for their recovery is adopted. Ac-
cordingly, in the spring of 1892, I designed and built, at the
Hanauer Smelting Works, the following plant for the above
purpose :
Ten feet from the front of the blast-furnace room, and parallel
. A PLANT FOR GRANULATING SLAG. 109
with it, is placed an underground trough, 2 feet wide and 6 inches
high, inside dimensions ; it is provided with an auxiliary bottom
of cast-iron plates, i inch thick, it having been found that wood
was cut away too rapidly ; this trough has a pitch of J^ inch to
the foot; its dimensions and pitch were the subject of much ex-
perimenting, in order to secure the highest efficiency of a limited
quantity of water in its double duty of granulating the slag and
and carrying it to an elevator pit, 133 feet distant from the re-
motest blast-furnace; opposite each furnace is a rectangular open-
ing, leading from the trough to the face of the dump, and covered
with a suitably flanged cast plate; it is here where the tapping of
the slag pot is performed; the maximum depth from the surface
of these plates to bottom of trough is 36 inches ; if greater it was
found the operation would not be successful, as the momentum of
the ij^-inch stream of slag caused it to solidify on the bottom
plates.
The smallest quantity of matte present produces a succession
of sharp explosions, not dangerous, but warning the furnaceman
that the settling vessel needs to be exchanged for a fresh one ;
where the usual plan of tapping the waste slag into another pot or
on the dump is pursued, the waste of matte is unavoidable.
Water for the operation is supplied by gravitation from the power
head-race, 1 3 feet above the tapping floor.
The granulated slag is carried away with sufficient rapidity to
admit of four furnaces tapping their slag into the trough simulta-
neously ; it is delivered to an elevator pit, water-tight and 8 feet
in depth — all that could be obtained conveniently, being level with
the canyon stream, Big Cottonwood, into which the waste water of
the works is discharged.
This depth of pit was necessary to prevent any considerable
overflow of small particles of slag into the stream — contrary to
law; an ample settling tank is also provided ; from this pit the slag
is lifted 40 feet for easy delivery by gravitation into tram cars, or
railway cars, or a storage bin of 100 tons capacity, sufficient for
twelve hours' run nights, when there is no organization to handle
it; the elevator belt is eight-ply 8-inch rubber, and its life, under
constant use, is one year; the most durable bucket is found to be
of malleable cast-iron; for motive power a 15-inch Leffel mining
wheel is employed, and having its gates so shortened, under the
length of the standard wheel of this size, that but 3- horse-power
I lo THE QUARTERLY.
is developed when they are wide open ; this was an expedient to
attain the desired speed of 550 revolutions per minute; the speed
of elevator is 250 fe:t per minute.
Wherever the angular and abrasive slag impinges or flows, pro-
tection by iron plates is necessary.
Regarding the uses to which the material may be put, none
have yet been found ; it is very brittle (lead furnace slag), abso-
lutely without cohesion, and will all pass through a J^-inch mesh
sieve; the local railways have tried it extensively for ballast ; it
will prolong the life of a wooden tie, and will not blow like sand,
but it does not kill weeds which it was hoped it would do, and it
does not pack ; experiments are now under consideration to pro-
duce a coarser material suitable for ballast and one that is less fri-
able, but it is believed this condition will not be attained except by
sacrificing in some degree the great economy of handling, for
which the plant was installed.
The granulation of slag offers unusual facilities for sampling and
weighing the daily product of this material ; in fact, it is the oftiy
system by which the loss in this channel of lead and silver can be
arrived at with anything like satisfaction; this knowledge is here
gained with all the accuracy that obtains in sampling concentra-
tions ; every metallurgist knows what an inhomogeneous a thing
a pot of cold slag is, varying from a comparatively rich outer
shell to a barren and crystalline interior.
Salt Lake City, December 5, 1893.
A RELATION OF ENGINEERING TO PROGRESS
AND CIVILIZATION.
By F. R. HUTTON, C.E., Ph.D.
An element which doubtless added much to the enjoyment of
every visitor to the Columbian Exposition was the faultless critical
faculty with which the governing authorities made their selections.
In no other respect was this more manifest than in the choice of
him who was to select suggestive and appropriate mottoes to be
worked into the decoration of the buildings.
It would, perhaps, be an unnecessary inviting of controversy to
RELATION OF ENGINEERING TO PROGRESS, in
say that engineers in particular, visiting the Fair, were impressed
with the selected mottoes for the Transportation Building, and this
the more by choosing such mottoes from writers who lived suf-
ficiently in advance of this century of progress to have their intui-
tive perceptions of great truths amount to a prophetic forecast.
One of the many definitions of genius is that it is a power to see
and record truths which every one knew, but was not able to an-
nounce, but in the case of Lord Bacon and the quotation credited
to him, the achievement rises further and higher than this when
account is taken of the conditions prevailing when it was uttered.
The quotation which the writer seeks thus to commend, and
whose import is not appreciated by the great mass pf the general
public is in these words: ** There are three things which make a
nation great and prosperous ; a fertile soil, busy workshops and
easy conveyance for men and goods from place to place." If it be
true that the relations of engineering to the greatness of a nation
are not generally realized to-day, the light of this solitary seer
in the past gleams out upon the student so much the more bril-
liantly.
Bacon was a philosopher of the Elizabethan period of England,
his active service running forward into the beginning of the first
James, of the House of Stuart. At the end of the sixteenth and
the beginning of the seventeenth centuries, Leeds, Manchester,
Birmingham and the other industrial centres of England were but
modest towns, distinctly provincial, and without noteworthy influ-
ence upon the national life. The profession of arms was the road
to honor and preferment; the Crusades were not so long in the
past ; the Reformation was but a hundred years in the perspective.
The puddling of wrought iron was many years below the horizon ;
the Marquis of Worcester and Papin belong in the latter part of
the seventeenth century. The whole industrial system, so far as
it existed at all, was based on the principle of individual labor by
master workmen, whose shop was in his own house, and whose
apprentices were members of his household. Beside those me-
chanic arts attaching themselves to the needs of the warrior and
the husbandman, the weaver was by far the most important, and
special emphasis had been given to this craft by the escape into
England of so many of the industrious and conscientious Hugue-
nots expelled from France by the revocation by Louis XIV. of the
Edict of Nantes. When Bacon therefore speaks of busy workshops,
1 1 2 THE QUARTERL K
to him they mean the individual establishment of the craftsman, and
not the busy hive where the labor of many hands was concentrated
under one management in what we of to-day call a factory or a
workshop.
But this only adds to the wonder that in his outlook upon the
conditions which make a land great and prosperous, the philoso-
pher should have generalized from small to great, so that his clear
vision should have been able to appreciate and his analytical mind
to formulate the relation which engineering in its modern sense
bears to national progress, and is likely to bear even more and
more as the forces of Nature are made by the engineer more and
more the servitors of man.
In the rise and progress of a nation, whether it originate in a
virgin land by colonization or by conquest, it will be a matter of
the most immediate and vital consequence that the soil of the new
land be a fertile one. The husbandman will be the first laborer in
demand, because the infant colony or the struggling settlement,
with its women and children, must be fed. The craft of the hunter,
also, in a new country, and the fisherman, will be of great moment
in conjunction with the farmer. It is apparent, however, that if
growth and development stop here, the community will be a small
one, with limited demands, and probably limited achievement of
any sort. It will remain a hamlet merely, and is not likely to
grow to a centre of intellectual or other activity.
The reason for this is not far to seek. In the nature of the
case, a purely agricultural country to be successful must not be
too densely populated to the unit of area, since for economical
husbandry, as in manufactures, the secret is a large output, with
a comparatively small outlay for labor. This means, therefore,
large farms, with a comparatively small number of persons living
on them, whereby the farmsteads become remote from each other.
There will be a central settlement where the blacksmith and the
house-builder and the tailor and the store-keeper will have their
abodes, but the idea of the city is impossible under these con-
ditions.
By the natural increase, however, and a probable influx by emi-
gration, an increasing number of men forms a part of the little
community, and they must be bread-winners. The farm does not
want them, and labor must be found for them in some other de-
partment of industry. The large farm, moreover, with a fertile
RELATION OF ENGINEERING TO PROGRESS. 113
land, produces more than those living on it will consume, and if
the prices of their commodities are not unduly to fall, a demand
must be created in their neighborhood or transportation must be
furnished. This concurrence of a supply and a demand in a settle-
ment of this sort is the beginning of manufactures, and the busy
workshop springs up — first, in the segregrated units of the earlier
day, and later, by the aggregation of many workers in one great
establishment. The necessity for the support and the supply of
the needs of this workshop or factory population, which will now
become very dense per unit of area for the best conditions, will
attract the exchangers of commodities; stores must be provided,
which again call for a class of laborer who will live densely over
the area which he serves, and the result of these two forces will be
the city. It is a platitude of the inspection of recent census re-
ports that the development of the modern state shows an enor-
mous increase in the sizes of the cities. We have here in the fore-
going considerations, apart from any questions of sentiment, the
reasons which in a prosperous nation point to this very result.
It is also an interesting question which, although aside from the
direct matter under consideration, is at once suggested at this
stage, and that is, that the consolidation of industrial interests,
which is a feature of the industrial life of to-day, is Jtist as unmis-
takable a mark of progress for the country at large, in the direc-
tion of the cheapening of manufacture, as the consolidation of the
segregated workers into the aggregate of a factory has resulted in
a noteworthy cheapening of product for the community at large,
while the compensation of the laborer is even greater in propor-
tion than under the old conditions. The period of transition from
the one system to the other is the period of hardship. It is also
suggested here to the thoughtful that that national policy which
encourages the development of manufactures within the nation
and builds up the busy workshops of the philosopher is the one
which developes the cities, which, with all their dangers, are yet
the centres of intellectual and spiritual force in the nations of the
earth.
The thinker must supply for himself the function which the
engineer has exerted in the development of the factory and the
city, which is its consequence. The busy workshop of to-day is
but a creation of the busy brain of him who applies the force of
heat'or gravity to the turning of the hundreds of whirling wheels,
1 14 THE QUARTERL Y.
and who has transmitted and converted the motion thus made
available for the myriad purposes which his brain has evolved.
But the philosopher saw further than this ; he saw that a j:;reat
and prosperous nation could not be a nation brought up without
homes, or whose homes were not comfortable and happy and
sunny. Knowing well his countrymen and the deep-rooted in-
stincts of the Anglo-Saxon race, he knew he would not be per-
manently contented when his home life also was conducted in an
aggregation of families under one roof. He may not have fore-
seen the tenement house, but he knew what it meant for the
worker to come refreshed each morning to his toil, from the inde-
pendence and the dignity which surround him who is at the head
of his own private house. He foresaw also that the history of the
husbandman would repeat itself for the manufacturer, and that he
would produce more product than could be economically disposed
of in the city of its origin. He said, therefore, that a third ele-
ment was necessary to secure the greatness of his prosperous
people. They might be prosperous with the other two, but they
would not be great. That third element for this greatness and
prosperity is '* easy transportation of men and goods from place
to place."
For men, this easy transportation means suburban homes, out-
side of the restricted area of the cities; it rheans for another'class
the culture and intellectual stimulus which comes from travel and
new scenes. For things, it means a whole country for a market,
perhaps the world ; it means a lowering of barriers for commercial
intercourse ; it means a reduced cost of articles manufactured to
the community as a whole, so that if wages are not lowered at the
same time there is a larger balance which passes to the commu-
nity for those elements which go to uplift it and to move it upon a
higher plane. The artist, the historian, the literary man, are all
the products of this latter phase of a nation's rise.
As before, it were idle to point out the relation of the engineer
to this feature of development. The civil engineer lays out roads,
canals, and the railroad. The mechanical engineer applies his
motive power by water and rail, and men and goods are conveyed
with increasing celerity and certainty between their objective
points. If the flying machine is to make communication as free
as air, it is by the engineer that its. work will be done. ,
It is unfortunate for the engineer that his work, fundamental to
MECHANICAL PREPARATION OF ORES. 115
so much which makes the comfort and civilization of the day,,
should be concealed and disregarded simply becau-«e it underlies.
Without the engineer, life in cities would be impossible where
there was no gas, no water supply, no sewage, no food supply ex-
cept by wage ns, no motive power but human muscles. There
would be a patrician class served by a class of slaves, and that
great, powerful, conscientious, reliable middle class, which makes
a nation great and prosperous, would be unknown.
Even in the Columbian Exposition, which has bten considered
the flower and example of what this century has done in the way
of artistic culture and industrial progress, beneath the architectural
beauty and genius of conception there lies concealed and em-
bedded many weary months of a burning of midnight oil, and of
the expert skill of the engineering toiler in the preparation of the
ground and the erection of the structures. Those who delighted
in the luminous fountains by night and the marvellous effect of
illuminations and the ghost-like flitting of the launches on the
lagoons gave, probably, hardly a thought to the pulsing pumping
engine, and to the whirring dynamo, over whose production the
engineer had presided, and over whose regular march a faithful,
conscientious, but unseen toiler, was watching with a ceaseless
attention, and he also an engineer.
These things make a nation great and prosperous, a fertile land,
a reverent, painstaking, capable body of professional engineers.
PRESENT CONDITION OF THE MECHANICAL PREPA-
RATION OF ORES IN SAXONY. HARTZ
AND RHENISH PRUSSIA.
By M. MAURICE BELLOM.
(Continued from p. 33.)
Since the year 1886, when Mr. Linkenbach gave this descrip-
tion, the tables have been perfected in many respects, which should
be mentioned.
All appear to have abandoned the superposed tables, except the
works at Ems. These have the great inconvenience of rendering
access to the two lower tables impossible. It is enough to pass
ii6 THE QUARTERLY.
through these Works to see that it is impossible to determine the
character of the work being done on these two parts of the appa-
ratus. The inconvenience resulting from the oscillations off the
superposed turning tables are not encountered with the fixed Lin-
kenbach tables ; but the shadow cast by each on the one below is
very unfavorable for the proper conduct of the washing.
Besides, in the earlier tables, which are described, the apparatus
for discharging by pipes of varying length was rotated by means
of a chain. This mode of transmission has been entirely aban-
doned in favor of gear-wheels, as shown in Figs. 45 and 46 which
over, the use of plates of zinc of variable size has been abandoned,
because it is more difficult to regulate them than the pipes of dif-
ferent lengths.
Finally, the type of hollow shaft, see Figs. 47 and 48 have been
substituted for the annular gutter (k) which, in the table shown in
shaft at its upper part.*
The revolving tables rarely exceed 5 m. in diameter, but the
fixed Linkenbach table may be of greater dimensions. By modify-
ing its size, this apparatus, therefore, can treat various grades of
slimes. At Ems three tables, of 6, 7 and 8 m. diameter, are em-
ployed for the three grades of slimes, the third grade, which con-
tains the smallest particles, being washed on the largest table.
The inclination of the washing surface, which should be great-
est for the coarsest grade, is, at Ems, \ for the 6 m. table, ^^ for
the 6.5 m. table and y.j for the 8 m. table. The tables make three
revolutions per minute; each table treats 120 liters per minute,
consuming 150 liters of wash-water, two-thirds of which is used
for the washing proper and one-third for carrying off the washed
products. The power required is jV H. P. per table when the
tables are single, and -^^ H. P. for a set of three superposed tables.
The slime should contain not over 10 per cent., by weight, of
solids.
The capacity, as expressed in the weight of slimes treated on
the Linkenbach tables at Ems, is as follows :
* The Huinboldt machine-shops (near Cologne) have adopted these last arrange-
ments for the table which ihcy construct and which are used for the mechanical prepa-
ration of pliosj)hates from Saint Symphorien, near Mons (Belgium).
MECHANICAL PREPARATION OF ORES.
117
Largest (ist grade), on 6 m. table,
Intermediate (2d grade , on 7 m. table.
Smallest (3d grade) *• 8 •*
720 kilos per hour.
660 "
600 **
•(
i(
Two men tend eight tables, assisted by a laborer, who shovels
out the products deposited in the tubs — in all, three men, or three-
eighths of a day's work per table.
The following table shows : *
.Pribram.) t«^^"-'5 . (Em,.,
Shocks per minute
Revolutions per minute
f
Large
Medium .!
Small
200
240
240
120
150
240
Amplitude of shock
(Cam displacement.)
Liters of slime treated per minute.
Proportionate weight of solids in slime
Liters of water used per minute.
1
i
f
1
{
Large..... 20 mm.
Medium .1 13 mm.
Small I 13 mm.
Large
Medium .
Small
Large ,
Medium. 1.
Small I,
3
L5
0.7
40 mm.
25 mm.
15 mm.
12
10
6 to 7
120
120
120
20 pr. cl. 9 pr. ct.
I 15 " I 9
12 « 9
I*
Large
Medium .
Small. ...
Horse-power required
Workmen (working days) pr. machine.
74
74
74
.50 to .75
1
Production per hour.
I
Large 225 kgs.
Medium .
Small
125
75
40
30
24
.50
144 kgs.
90 "
50 "
150
150
150
.10
f
720 kgs.
660 "
600 "
1. The figures for the Rittinger tables, as given by Mr. Henry
for the Przibram works {Annales des Mines, Seventh Series, Vol.
II., 1S72, p. 292).
2. The actual figures for Rittinger tables of the same size (2.4
meters long and 2.4 meters wide), as shown in the Rhenish dress-
ing-practice.
3. Figures obtained at Ems with Linkenbach tables.
Attention is directed to the excessive values of the figures for the Rittinger table,
and it is said that these machines can treat from 3 to 6 tons of slime in 10 hours,
whereas, in fact, I ton should be considered a maximum. — M.B.
1 1 8 THE QUARTERL Y.
The comparison is in favor of the Linkenbach table, as regards
the requirements for power and labor, even conceding the Rittin-
ger a greater capacity than one ton in ten hours (/>., lOO kilo-
grams per hour), which German engineers at the present day dis-
pute. It is true that the enrichment of the pulp is comparatively
slight at Ems. For reasons that will appear later, the galena is con-
centrated only to 38 per cent, of lead and 30 grams of silver per
100 kilograms of galena. But it is easy to cite the example of an
ore treated on a Linkenbach table, where the concentration is
carried much further. At the works of the Neuhof mine, near Beu-
then, Upper Silesia. The ore consists of galena and calamine in
an argillaceous gangue ; the crude ore contains 4 to 5 per cent, of
galena, carrying 56 to 6o grams of silver per 100 kilograms of the
granulated mineral, and 50 to 80 grams per 100 kilograms of sands
or slimes. The clean fragments of the calamine carry as high as
45 per cent, of zinc. A Linkenbach table treating 280 kilos per
hour yields galena carrying 60 per cent, of lead, carrying 60
grams of silver per 100 kilograms of mineral, and a calamine car-
rying 10 per cent, of zinc and from 0.5 to 2.0 per cent, of lead.
This enrichment to 60 per cent, of lead, which agrees with results
obtained at Przibram and cited by Mr. Henry, is sufficient to refute
It may be well to add that the Rittinger table requires more
skillful control and attention than the Linkenbach table, and that
the waste products of the former are rarely lean enough to be
Classification by Air Blast.
In the apparatus used at Himmelsfurst, Saxony, the mineral is
spread on an endless belt. A, Figs. 49, 50, 51, travelling in the
direction of the arrows, and the current of air is directed upon it.
The rubber belt passes over the table, E, and over two rollers, C
and D, its tension being regulated by the two small rollers, R and
R*. The blast is conveyed through a pipe, M, and distributed
over the surface of the belt by means of nozzles, T, T^ T", T"\
T*^. The ore from the hopper, V^ is spread over the belt. A, by
feed-wheel, U, which is run by the pulleys, X and X*. A guide,
'" "'~"ed near the hopper, V, above the belt, and several leather
'so set above the belt, promote a uniform distribution of
rial. The boxes, S, S^ S", S"^ and S'^ receive the dif-
MECHANICAL PREPARA TION OF ORES.
119
ferent products of the separation. The orifice, O, of each blast-
nozzle. Figs. 51, 52. 53, is easily regulated by the screws, H and
K, each screw controlling the position of one of the sleeves, P and
Q- The screw, which is set by a hand-wheel, is of sufficient length
to adjust the position of the sleeve, Q. through an arc of 10 mm..
Fig. 49 (Scale 5^0 )
as shown. The maximum angular displacement that can be given
to the sleeve P is, likewise, 10 mm. The blast is furnished by the
fan, W, which makes 1275 revolutions per minute. The fan is
run by a small steam-engine, which also drives the shaft, B, from
w^hich power is transmitted to the pulleys, Y and Y'.
Fig. 50. (Scale ^5.)
The principal dimensions, etc., of the apparatus are as follows:
Length of belt. A, exposed to the blast, .
Width '• »•
Velocity " per second,
Length of pipes,
Distance between centres of nozzles.
I910 mm.
480 •'
no ••
250 •'
350
t(
I20 THE QUARTERLY.
The box J receives the products which have not been blown
III., IV. (Scale j'j.)
from the belt into the boxes, S, S', S", S'", and S'". In the case
of a lean ore the products will be about as follows :
1. Product received in S harren (rejected).
2. " S' •■
3. " •' S" intermediale (rctrealtd).
4. " .< jjill .1
5. ■' ■• SI'
6. " ■' J finished product .for ihe smeller),
FiG. 52.
Section 1., 11. (Scale ^„.)
In applying this method of dry separation on a large scale, it is
preferable to increase the number of machines rather than the ca-
F.0.S3. (Scile^.)
pacity of each machine. Since the blast acts only on the upper
^lyer of the material on the belt, it is obvious that the transfer of
MECHANICAL PREPARATION OF ORES.
121
the material from one belt to another in series, occasions a certain
amount of mixing that may bring to the surface particles, which
had they remained upon the first machine, would have escaped the
action of the blast. Thus in place of a table with twenty nozzles,
it is preferable to use four tables of five nozzles each.
Expcrbnents. — In order to show the results obtainable by this
method of classification, the engineers at Himmelsfurst have made
numerous experiments, from which I shall select six that appear
to be of the most interest.
The first three experiments are on three different grades of an
argentiferous galena ore, containing blende ; the last three are
likewise on three grades of material obtained in the treatment of
another ore of similar kind. The first of these ores was stamped;
the second was ground. In the first case the material to be classi-
fied by blast is composed of sand and slime; in the second case it
consists of every grade of sand, using this term as previously de-
fined, to include products which are not finer than 0.25 mm.
The results of the two series of experiments are shown in the
following table :
Stamped Ore,
Wiights.
Kil..s. I Pcrct.
Percentage; Composition.
Ag.
Pb.
iJ»t Experi-
ment.
to 2 mm.
Raw product 22.5 100 0.065 ^3-5 ' 6.0
1° and 2° product from
1° and 2° boxes.
Marketable galena.
Intermediates.
^ Losses
12.3
3.2
i.3
5-7
54.67
14.22
5.78
25.33
0.050
0.185
0.140
0.130
2.5
71.0
50.5
11.5
3.4
15.0
18.0
10.4
Zn.
6.
5.
4.
5.
6.
I Raw product 12.2
1° and 2° product from
1° and 2^ boxes.
2d Expcri-
ment. . i^^arketable galena.
Grade, i to j ,, '^ ..
1.5 mm. I Intermediates
1^ Losses
5.2
3.0
i.o
3.0
1 00. CO 0.085 27.5 7.8 4.
42.62
24.59
8.20
24.59
0.073 4.5
O.It)2 71.5
0.280 ' 41.5
o. 115 ; 9.5
3.4
I5.I
14.8
7.3
3-
3.
5.
5.
3d Experi-
ment
to 0.5 mm.
f Raw product 24.6
1° and 2° product from
1° and 2° boxes 4.6
Gr^r'o.^ < Marketable galenn 7..
Intermed iates 7.6
Losses
100
0.145 Zl'^ 8.0 5.0
I
18.70 0.045 1 0.2
28.86 o. 160 70.0
15.45 0.235 51.5
30.89 0.132 4.5
6.10
4.8
15.0
12.6
5.0
3-0
3.0
4.6
4.0
VOL XV. —9
122
THE QUARTERLY.
Ore Ground in Mills,
Weights.
Kilos.
Pe. ci.
Percentage Composition.
1st Experi-
ment.
1.5 to 2.5
mm.
Kaw product
(1°) and (2°) products
from 1st and 2d boxes'
(3°) galena :
(4°) mineral J '
(5°) products furnished
by the intermediates
in I si and 2d boxes...
(6°) mineral II
(7°) mineral III t
(8°) intermediates |
l^osses
500.0 loo.o
25.2
36.4
113-2
104.5
92.0
107.0
23.0
2d Ex peri
ment.
I. to 1.5
mm.
' Raw product
(I®) and (2°) products
from I St and 2d boxes
(3°) galena
(4°) mineral I
' by the mtermediates in
the Island 2d boxes...
(6^) mineral II
(7°) mineral III
(8°) interme<liates
Losses
265.5
34.0
32.3
45.0
42.3
52.8
3?.o
22.5
Ag.
0.102
Ph.
5.04 0.035
6.88 ; 0.312
22.64 \ 0.125
20.90
18.40
21.40
4.6
0.14
0.020
0.065
0.050
.022
7.5 16.2
0.2
32.0
9.5
0.2
3.5
2.2
0.2
S.I
23.7
23.8
4.8
17.3
>»-3
6.5
loo.o 0.122 8.^ 8.8
12.S1
12.17
16.95
0.036 1.5
0.492 50. 5
0.182 ' 13.5
15.93 0.052 1.5
19.89 0.072 3.5
13. 18 0.046 i.o
8.47 0.027 1.5
0.60 I
5.6
20. I
'9.3
7.2
8.8
7.2
C.6
3d Experi-
ment.
0.3 to 1.0
mm.
Raw product
(1°) and (2°) products
from 1st and 2d boxes
(3°) galena
(4°> mineral I
iirLiii. . oj products furnished
Grade from ^ ^-^i lu » i- » •
' by the intermediates in
1st and 2d boxes
(6°) mineral II
(7°) mineral III
(8°) intermediates
Losses...
989.0 lOO.o 0.1 15 10.2 12.8
139-4
103.7
128.6
216.0
193-8
157-8
35.0
14.09 0.031 0.2
io.49 0.555 I 53.2
13.0 0.212 ' 15.5
21.84
19.6
15.96
3.54
1.48
0.030
0.091
0.072
0.032
0.2
5.5
3.5
1.5
10.2
20. 1
20.0
9.6
15.2
II. 6
8.7
Zn.
9.0
4.0
9.
9.
4.
8.
7.
4.
9.
6.
7.
9.
6.
9.
6.
9-0
7-0
9.0
II. o
6.0
10.
9.
6.
In the first experiment of series No. I, the enrichment of the
galena was perfectly attained ; a mixture of the two grades of
galena giving a product containing over 60 per cent, of lead. The
second experiment also showed excellent results, attributable to
the texture of the ore which is particularly favorable for the sepa-
ration of the galena. The third experiment was equally satisfac-
tory; the two galena products which together aggregated 44.3
per cent, of the crude pulp, carried over 60 per cent, of lead. The
MECHANICAL PREPARATION OF ORES. 123
t'wo remaining products of this experiment were also finished
products.
In the second series of tests the first experiment gave less than
7 per cent, of galena which carried less than 33 per cent, of lead;
moreover, though the lead in the waste products ran below 0.2
per cent, the quantity of silver was over 0.02 per cent. Wet treat-
ment in this case would not have given more favorable results,
since with such high silver contents in the pulp the losses would
have been serious. A comparison between the value of the crude
pulp and that of the concentrate by either wet or dry treatment
shows that it would have been more advantageous to send the
crude material directly to the smelter without any previous treat-
ment. The second and third experiments, although more favor-
able in results, lead to the same conclusion.
Bearing in mind that in the first series of experiments the pulp
contained a higher percentage of galena than in the second series,
and also that this dry method of treatment is less suited to slimes
than to sands, the Saxon engineers have drawn the following
conclusions:
1. Classification by blast should be applied preferably to ores
rich in galena.
2. Dry stamping, which produces too much dust, should be used
only for granular ore such as that treated in the first three ex-
periments.
3. The Saxon roller-mills which give only 20 per cent, of their
product coarser than 0.2 mm. as against 60 per cent, for stamps,
may be employed for crushing the material that is to be separated
by the blast.
4. Slimes should be washed or should be delivered direct to
the smelter. During the course of the foregoing experiments, the
slime-pulp was sifted through a sieve of about 800 meshes per
square centimeter.
5. The products most easily classified by blast are those which
range between 0.5 and 1.5 mm. ; if the particles are too large they
are not easily moved by the blast. Though close calculations have
not been made, it is admitted in Saxony that the cost of the dry
separation is higher than that of wet stamping followed by jigging
but lower than the cost of crushing the ore in a rock-breaker and
rolls.
Ore crushed by rolls and containing at least 5 per cent, of lead
will be advantageously treated by blast.
124 THE QUARTERLY.
The second series of the experiments shows a concordance be-
tween the economic results of this method of separating and those
obtained by washing on tables. As compared with the wet treat-
ment the dry method permits a more constant control of the pro-
ducts and reduces the sources of loss.
VII. Magnetic Treatment.
Magnetic treatment is applicable to products whose densities
are too closely allied to permit the use of ordinary dressing
methods.
Zinc blende associated with spathic iron is such a product, and
is treated by magnetic separation at the Friedrichssegen works.
Magnetic separators may be classified according as they have
permanent or electro-magnets. Separators of the former class are
the less costly but their capacity is small — the Vavin separator,
for example, never treating more than 200 kilograms per hour,
whereas the electro-magnetic apparatus at Friedrichssegen treats
500 kilograms in the same time. The interruptions of the cur-
rent at pleasure, and consequently of the attraction of the soft iron,
in the case of the electro magnet, dispenses with the use of brushes,
which in separators of the Vavin type, are necessary for removing
the attracted particles of iron. The brushes wear away rapidly
and by retaining iron particles between their bristles they become
a source of expense and loss of mineral.
In electro-magnetic separators we may distinguish between
those, like the Sella machine, in which the current is interrupted
at intervals, allowing the particles of iron attracted by the magnet
to fall off and those in which the current is continuous and the
separation of the attracted particles is effected by carrying them
out of the magnetic field. The last method, which is evidently
the simplest, since it can be operated by merely displacing the
separating surfaces with respect to the electro-magnets has been
adopted in the machine at Friedrichssegen.
The latter. Figs. 54 and 55, is composed of a brass drum. A,
moving around a fixed horizontal shaft, H, which carries four
.set3 of fixed electro-magnets,. B.. A sheet iron oscillating distrib-
uter, D, feeds the material from a hopper to the drum. The dis-
tributer is inclined, and suspended by four links, and is oscillated
by a cam, as shown.
The ore on reaching the drum is submitted to the attraction of
the electro-magnets. A series of projections (S), parallel to the
MECHANICAL PREPARATION OF ORES.
125
axis of the drum tend to retain the materials, and thus promote
the attraction of the particles of iron ; the non-attracted zinc parti-^
cles fall into the box below (Z). The iron particles are quickly
carried beyond the magnetic field by the rotation of the drum in
the direction shown by the arrow, and they then fall into the box
(F). The current from a dynamo enters through one end of the
Fig. 54. {Scale ^j.)
Fw. 55. (Scale j^^.)
hollow shaft (H), passes into the coils and then returns to the
dynamo by way of the other end of the same shaft. The motion
of the pulley, P, is communicated to the drum and-transmitted by
it to the pulley, R, which is belted to the cam shaft (Q) of the dis-
tributer. The apparatus can ireat particles of various sizes de-
pending on the distance, which is regulated by the screw (V), be-
tween the drum and the lower end of the distributer.
A Siemens dynamo, using one horse- power, is sufficient to
run four separators, each treating 500 kilograms per hour of a
mixture of blende and oxide of iron like that of Friedrichssegen,
126 THE QUARTERLY.
«
the composition of which will be given with the description of the
works. The rotation of the drum consumes only one-sixth of a
horse- power. The dynamo furnishes a current of yj amperes and
makes looo revolutions per minute; the brass drum makes 45
revolutions and the cam-shaft 400 revolutions per minute. One
workman can manage four machines.
This apparatus has the following advantages : (i) The electro-
magnets being fixed and enclosed in the brass drum, which pre-
serves them from dust, very seldom need repairs. (2) The
capacity, compared with other types of electro- magnetic machines
is high, the test made at Przibram with a machine having an inter-
rupted current gave, as a maximum, an hourly production of only
1 50 kilograms.
Results of the Mechanical Preparation.
Rnrkhment.
To enrich the crude ore is the great object of mechanical prep-
aration ; the losses which always accompany all operations of this
kind naturally tend to set practical limitations to the degree to
which concentration may be profitably carried. It is expedient,
therefore, to determine in each case the point at which the result-
ing losses in the treatment are greater than the enhanced value
given to the products by the concentration. Owing to the nature
of the ore and the distribution of the rich minerals, which are not
always the same in the vein-rock as in the enctosing wall-rock, it
may be found desirable to keep down the degree of concentration.
At Ems, for example, a close study of the composition of the vein-
rock and the barren rock resulted, several years ago, in limiting
the enrichment of the galena to 36 per cent, of lead instead of the
former practice of carrying it to 60 per cent.
Though the vein- rock (at Ems, as will be described later) carries
more galena than the wall- rock, the galena of the latter is the
richer in silver. Similarly, the relation between the lead- and
silver-contents of the sands and slimes at Mechernich has exerted
a controlling influence on the scheme of treatment there, as will
be shown.
Calculation of the Total Losses.
German engineers use one of the two following methods:
I. For ores of uniform regular mineralization, the facility with
MECHANICAL PREPARATION OF ORES. 127
which they can be sampled furnishes an easy method for calcu-
lating their average percentage composition, from which the weight
of metal contained in the crude ore may be calculated, and from
the number thus obtained the corresponding weight of metal in the
finished product is deducted in order to find the weight of metal
which has been removed with the waste during the treatment of
the given weight of the crude ore.
2. For ores of irregular mineralization, however, it is necessary
to compute the metal contents in waste products from each sepa-
rate operation.
Knowing the weight of the several waste products, the weight
P of the metal they contain can be calculated. Moreover, know-
ing the composition and weight of each of the final products, it is
easy to compute for such of them as do not furnish the metals in
question, the weights, p, of that metal contained as waste in said
products. The aggregate of these weights, 2*/, added to /'gives
the total loss (Z = /^+ 1 p) of this metal in question for the quan-
tities of the products considered, and these are derived from a
certain known weight of crude ore determined by direct weigh-
ing.
If it be desired to compare the loss of a given metal with the
weight of this metal in the crude ore, the composition of the latter,
as furnished by direct analysis, cannot serve as a basis for compu-
tation on account of want of homogeneity of ore. In place of this
method, therefore, which answers only for ores of uniform and reg-
ular mineralization, another should be substituted, the principle of
which is as follows : A direct analysis gives the percentage of the
particular metal contained in the final product which furnishes it.
Knowing the weight of this product obtained from a certain quantity
of the crude ore, the weight of the metal in question contained in
the final product can be deduced from it. Adding to it the weight
(Z) of the losses, the total weight of the metal contained in the
known weight of crude ore is obtained, and this, by simple propor-
tion, gives the percentage of metal in the crude ore.
When once this percentage is ascertained, whether by the
method used for irregular mineralization or by direct analysis, the
relation {R) between the loss computed for a weight of crude ore
equal to lOO and the percentage of metal in the same ore can be
determined.
The losses vary between wide limits. I subjoin the figures for
128 THE QUARTERLY.
the works at Himmelfahrt, Churprinz and Ems, the schemes of
treatment being reserved for later description :
1^. Himmelfahrt Works.
4
The ore treated at Himmelfahrt contains per lOO kilograms of
the crude material, 2.75 kilograms of lead, 0.275 kilograms of zinc,
23 grams of silver, 500 grams of arsenic, 10 grams of copper and
5 kilograms of sulphur.
By concentration, the galena is raised to 85 per cent, of lead and
300 grams of silver to 100 kilograms of galena ; the blende is en-
riched to about 40 per cent, of zinc, and 30 grams of silver to lOO
kilograms of blende, and the pyrites to about 40 per cent, of sulphur
with 50 grams of silver to 100 kilograms of product. The losses,
relatively to the contents of the crude ore (that is to say, the value
for each metal of the quantity (^) above defined) amounts to 21
per cent, for the silver, 38 per cent, for the lead, and 60 per cent,
for sulphur. That the losses are so high is due to the unequal
friability of the different minerals, crushed by stamping, and to
the carrying off of a part of the galena in the slimes. Although
the pyrites and the blende are argentiferous, they become so inti-
mately mixed in the course of the mechanical preparation that they
cannot be profitably separated or converted into marketable pro-
ducts. They therefore go to the waste-dump, and as they some-
times exceed in amount 20 per cent, of the stamped ore, the loss
is very great.
2°. Churprinz Works.
The ore contains 3 kilograms of lead and 9.5 grams of silver in
100 kilograms of crude ore. It is concentrated to about 70 per
cent, of lead and 50 grams of silver to 100 kilograms of galena.
The losses amount to 22.8 per cent, of the silver and 14.9 per cent,
of the lead contained in the ore.
3°. Ems Works.
Each 100 kilograms of crude ore contains 4 kilograms of lead,
2.5 kilograms of zinc and 5.4 grams of silver. The galena is con-
centrated to 36 per cent, of lead and 30 grams of silver to 100
kilograms of galena. The blende is worked up to 44.5 per cent,
of zinc and is not argentiferous. The losses amount to 8 per cent,
of silver, 6 per cent, of the lead and 34 per cent, of the zinc ob-
tained in the crude ore.
MECHANICAL PREPARATION OF ORES. 129
Calculation of the Losses for each Operation,
The Saxon engineers have recently made a series of experiments
which may serve as a type for the method of determining the losses
for each operation. The experiments were made for the pifrpose
of comparing the results of stamping and washing on the end-
percussion tables with the results of crushing by rolls and jigging.
The ore to be tested, of which the following table gives the
composition, was first crushed in rolls to 8 mm., and then sized
on screens to ascertain whether it would be advantageous to use
rolls and jigs before stamping. 48 cubic meters of the ore, weigh-
ing 87,100 kilograms, were thus tested. The products are given
in the first column of the following table, those numbered i, 2, 6,
^\j ^2**^3» ^2> ^8 ^^^ fi"^^ products. Nos. 3, 7 and b^ are mineral
bearing but unsalable, and their further mechanical preparation
would not be profitable, owing to low grade and price of the metal.
No. 4 is an intermediate product, which is to be stamped wet.
Nos. 5, r„ Tg, r, are rejected as barren.
The cost of mechanical treatment in this case amounts to :
Marks*
229 96 for salaries.
Ill .40 for power and labor.
I 47, cost of stamping 490 kilos nl jigfjed ore.
15.20, cost of washing 1 1.390 kilos of slimes.
28.80, delivery of the crude ore at the mills.
22.30, delivery of the market product.
409.13
Making 8.25 marks (^1.96) per cubic meter of crude ore.
The following table gives the figures for tire test :
These results have been compared with others obtained with
stamping and percussion tables in the same works. In treating
an ore containing 0.015 per cent, of silver, i per cent, of lead, 12
p>er cent, of sulphur and 8 per cent, of zinc, which yielded 19.7
per cent, of salable concentrates, carrying 0.009 P^^ cent, of silver,
0.44 per cent, of lead and 4.91 per cent, of sulphur, the pro-
ducts obtained consisted of:
a. 3^7 per cent, of galena, in which the silver varies from 0.105
to 0.175 per cent, and the lead from 30 to 54 per cent.
^. 3.4 per cent, of the jigged "lead-ore," in which the silver
* One mark equals 23.8 cents.
I30
THE QUARTERLY.
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MECHANICAL PREPARATION OF ORES. 131
varies from 0.09 to o. 1 15 per cent., and the lead from 22 to 29 per
cent-
r. 92.9 per cent. " dry " ore, or material in which the silver varied
from 0,03 to 0.55 per cent., the sulphur from 25 to 30 per cent.,
and the zinc from 7 to 14 per cent.
The yield, according to the foregoing figures, amounts to 59.3
per cent, of the silver, 44.3 per cent, of the lead and 40.9 per cent.
of the sulphur. The total cost of treating 2368 cubic meters, or
4.309,760 kilograms, of the crude ore amounted to :
Marks.
6,804.13 for labor in stamping, washing on tables and sorting the ore.
520.96 for labor in elevating the ore to the stamp-supply bins.
• 909.92 for materials.
13032 for hlacksmithing.
1,129.52 for labor in charging and removing the sands and slimes.
465.70 for repairs.
481 29 for tests.
727.80 for consumption of water.
1,627.60 for delivery of the crude ore.
4,778.54 for delivery of the final products.
7,573.54 total.
Making 7.42 marks ($1.76) per cubic meter of crude ore. The above figures show that the losses amount to 40.7 per cent. of the silver, 55.7 per cent, of the lead and 59.1 per cent, of the sulphur in the ore. These large losses are to be attributed to the character of the ore. Thus the loss of silver is largely due to the presence of a mixture of blende and iron pyrites, which sometimes amounts to 25 per cent, of the crude ore, and which has to be discarded, as it cannot be converted into a merchantable product. The two components of this mixture carry enough silver to create a loss up to 30 per cent. The sulphur in the mixture is also lost. As for the small yield of lead, it is easily accounted for by the presence of i to 3 per cent, in the "dry'* ore, which consti- tutes 92.9 per cent, of the final products. This **dry" ore, com- posed of blende and iron pyrites, cannot be concentrated for lead without considerable expense. So that the treatment is confined to the concentration of the silver to a point sufficiently high to allow it to be placed on the market. The loss of lead, which is carried off by the water from the stamped products, is very low ; it is in the form of the finest pulp produced by the breaking or 132 Tllh QUARTERLY. springing off of minute particles of galena from the large grains under the blow of the stamp. The losses on the washing-tables are somewhat large, on account of the re-treatments which are made necessary by the intimate association and complexity of the mixture to be treated. The following table gives comparative results for the two processes : Examining the figures of this table, we find : 1°. That the quantity of ore passed by stamps in a day amounts to 76 per cent, of the quantity crushed by the rolls in the same time. Twelve stamps were used in the test. This number would therefore have to be increased to fifteen to make the crushing ca- pacity of the stamps equal to that of the rolls. It should be noted, however, that the rolls crush only to 8 mm., while the stamps crush to about 3 mm. 2°. The marketable products from the stamps are worth about four times as much as those obtained from the rolls. Five times as much galena is produced, and only one-sixth as much lead-ore concentrate, but eighteen times as much dry ore. The rolls yield a large proportion of intermediate and unsalable products. The apparent discrepancy between these results is explained by the composition of the dry ore, which consists of a mixture of blende and pyrites containing 0.02 to 0.025 per cent, of silver, i per cent, of lead, 8 per cent, of zinc and 26 per cent, of sulphur — a product in which the lead cannot be profitably concentrated. 3°. The treatment by stamps furnishes about three times as much silver and five times as much sulphur as the treatment by rolls. 4^. The stamps yield a little less lead concentrate, owing to the better comminution by stamping, which gives a greater proportion of pure galena and a smaller quantity of ** lead-ore" concentrate (galena, with pyrites and blende), but which also produces the dry ore that still contains traces of galena. Thus, on the one hand a higher concentration of galena is obtained, and, on the other hand, some galena finds its way into the dry ore which goes to the smelter. In summarizing, we may say that crushing by rolls did not com- pletely disintegrate the crude ore. The more friable constituents of the ore — namely, the gneiss, carbonates, galena, and occasion- ally the blende — were crushed first, whereas the quartz and the MECHANICAL PREPARATION OF ORES. 133 Stamping & RoU.crush'g wushing on ^^^ ' percussion 1 :;„„:„„ ; tables. I J'8g'ng. Q*-. r » . I / kilograms, uaDtitv of ore treated < .^ ^ \ cub. meters. Days of work Quanlily of ore treated per day kilograms ("Salable concentrate I Non-salable •• Froduction \ Re-treatments I Total (^ Hence, losses and barren ore. f Salable concentrate I Non-salable •• Production j Re-treatments of silver. | Total I Barren rock from jigging [^ Total silver in the crude ore. 14 <4 <« «• << 41 44 44 4,309.750; 347 12,250 853300 853,300 3,45^450' 383 58' Production of lead. ' Salable concentrate « . Non-salable •• «• Re-treatments •• Total «• Compared with crude ore...pr. ct. Galena «• Lead-ore «• Dry ore •• r, » Non-salable products «• Perce ntage«i , . 1: . , **^ Intermediates ot products . i» 1 ^i*._r_. 1 ' Barren rock ♦« Hence, products carried by the water to the percus- sion table •' Losses from jigging, and on 1^ stationary tables •• silver 383.58 "**383-58' I 19,067.501 '•••••••■•■•■•I 19,067.50 19.7 ' 0.7 { 0.6 ' 18.4 obtained. ( silver \ < lead [-per ct. ( sulphur) 25.0 55-3 Production of different metals, 100 parts ore -j lead sulphur Gross receipts per cubic meter of ore treated francs Gross receipts jier 100 kilograms treated •♦ Cost of the drei-^ing proper, per cubic meter of ore | treated .' •• Total cost of the dressing, including the delivery of the \ crude ore and of the Hnished products «• Net receipts per cubic meter •• Net losses •* •* •• 0.009 0.44 4.91 14.70 4.08 5.89 9.27 5.43 87,100 48 5K 16,500 4,130 19,920 14,490 38.540 48,560 ^327 4.912 2.173 9.412 3.^05 >3-2i7 610.50 31250 14500 I ,ob8.oo 4.74 015 3 53 1.06 22.87 16.63 43.70 10.47 1.60 0.0027 070 1.03 5.34 6.18 932 1065 5.31 mixture of pyrites and blende in which some galena was dissem- inated, reached the jigs below the stamps intact. 134 7//A QUARTERLY. The jigs therefore yielded an intermediate product, which should be submitted to more complete disintegration, and a sulphur ore in which the small content of lead could not be economically con- centrated. To crush the ore with rolls to 3 mm. two pairs of rolls would have to be used, one for fine, the other for coarse crushing, and the cost would thereby be much increased, since the crushing of quartzoze rock with finishing rolls is, :is is well l:nown, more costly than stamping. The insufficient disintegration due to the use of rolls has also had this other result, that certain products, especially those marked No. 7 and b^, in the table on page 130, were not rich enough for immediate shipment to market, but required another treat- ment—a higher concentration of the galena and the resulting enrichment of the silver would undoubtedly have increased the gross receipts ; but it should not be forgotten that the treatment of small quantities of materials does not always enable us to real- ize for each operation the most economical results. Thus it appears that the use of stamps in S.ixony does not proceed from the mere desire to adhere to old apparatus, but that it is the result of close investigation and careful experiments. Cost of Dressing. The cost of dressing one metric ton of crude ore is as follows : 1°. At the Himmelfahrt Works. Breaking by hand, sorting and cobbing, Washing, followed by fine cobbing and jigging, Crushing with rolls and jigging. Wet stamping and washing on tables, Transportation, tests, assays, etc., Francs. 2.50 1-75 0.60 2.20 5.00 Total (per ton of crude ore), 12.05 2°. At the Ems Works. Francs, Breaking by hand and preliminary sorting, .... 0.34 Fine sorting, 1.05 Treatment of the fines, 2.01 Treatment of the blende and galena, 0.88 Total (per ton of crude ore), 4.28 MECHANICAL PREPARATION OF ORES. 135 The processes applied in each of these works differ too much (as will be shown later) for a comparison of costs. It can be readily seen that in the works at Ems there are no expenses for tests, and that the continuous plan used in these M^orks greatly diminishes the manual labor. The latter, in any event, must be higher in the Saxon works than at Ems, on ac- count of the complexity and greater richness of the Saxon ore and the higher degree to which it is concentrated — all of which conditions call for more skillful labor there than at Ems. Choice of Treatment. Though the diversity of the ores makes it obviously impracti- cable to subject them all to one scheme of treatment, it would be interesting to assume a general type of treatment, and to observe the part assumed in carrying out that type by the recent machines that have been described. No such type is to be found in any of the dressing works. The Schmitt-Manderbach classifier, for example, is employed only in Saxony ; Meinicke's sandsortir apparat is not used in the Rhine district; the spitzlutten apparatus of Meinicke is restricted to the Hartz, while the Linkenbach tables and the Schranz rock-breaker and roller-mill are met with only in Rhenish Prussiq. I shall endeavor to describe in brief such a typical treatment. By passing the ore over a grating, the hexagonal openings of which measure 60 mm. on a side, two classes (lump and fine) will be produced, and these will be treated separately. 1°. The lump-ore will be submitted successively to spalling and careful picking, and the products will be crushed to 8 mm. in a Schranz rock-breaker. The crushed material will pass to a drum- screen having 8 mm. holes; the rejections will go to rolls, and thence back to the same screen. The grains which pass through the screen will be sized in a Schmitt-Manderbach apparatus. Those larger than 3 or even 4 mm. will be treated in a continuous three-sieve jig, which will yield two final products and one intermediate product, which will be crushed in a Schranz mill to less than 3 mm. Sizing to i mm. will be done in the Schmitt-Manderbach apparatus ; below that limit a Meinicke sand-classifier is to be used. The various classes of grains smaller than 3 or 4 mm. will be treated separately on filtering jigs. The products carried by the 136 THE QUARTERLY. water beyond the sand-classifier will be conveyed to the spitzlut- ten apparatus, which will yield, say, three classes, each to be treated on a Linkenbach table. 2°. The fines will be put through a rotary washer and then through a Schmitt-Manderbach sizing- apparatus ; the rejections larger than 30 mm. will be hand-picked on a revolving table ; the sizes below 30 mm. will go to a Schranz rock-breaker, and thence through the same series of operations above indicated. This scheme of treatment is merely an illustration of the pres- ent ideas of German engineers in connection with the use of new machines. The discussion of the particular treatment to be adopted in each case is reserved for the second part of this memoir, in which the various modifications of the general type will be discussed. Choice and Relative Disposition of the Apparatus. The advantages or inconveniences of the various apparatus pointed out in our descriptions may aid in the selection of the particular apparatu$ best suited for any given case.
The machines should be so placed as to allow an easy transfer
of the products from one apparatus to the next. Where this
transfer is automatic, the machines are arranged in successive
levels, but where the products have to be handled between succes-
sive operations, the machines are placed approximately on the
same level, with sufficient room around each one to allow the
accumulation of the intermediate products pending further treat-
ment.
The works of Silberau, at Ems (referred to later), afford a re-
markable example of a plant of the first kind. The works of
Laurenburg (to be described further on) exemplify the second type.
It may seem surprising that the tendency to substitute mechan-
ical for manual transfer of the products has not resulted in the
complete abandonment of the . so-called non continuous plants.
Nevertheless, on close investigation, the maintenance of the older
type in works recently reconstructed, like those of Laurenburg,
appears logical when the continually changing character and com-
position of the ore are considered.
The plant at Steinenbriick furnishes another example where, in
remodelling the works, the non-continuous type has been pre-
served. But even in plants of this type there is a manifest ten-
MECHANICAL PREPARATION OF ORES. 137
dency to set in close juxtaposition the machines which necessarily
work together, such as the crushers and their accompanying sizing-
screen. Whatever their claims, however, the number of non-con-
tinuous plants has been notably diminishing for some years, and
their existence can only be justified by exceptional circumstances
such as those which prevail at Steinenbriick and Laurenburg.
No improvements in the feed or distributing devices have been
scribed.
In the removal of the jig-products the tendency to economize
in manual labor is apparent.
Thus, in the works at Weiss the product from the last compart-
ment of the jigs falls directly into cars, the side-walls of which are
made of perforated sheet-iron, so as to allow the water to drain off.
When the car is full two men push it away and replace it by an
empty one. This method does away with the labor of shovelling
the products from the tubs that are usually placed below the jigs,
yet the method is only applicable when water is cheap and abun-
dant and does not have to be saved.
General Plan of the Works.
The general arrangement of a dressing-plant depends primarily
on the site, and this is quite as true of a plant designed for con-
tinuous as for non-continuous working.
Among the works to be presently described I have selected
four that correspond to widely different conditions of site.
1°. Works at Friedrichssegen, in a very narrow and steep
vallev.
2^. Works at Weiss, on evenly sloping ground.
3^. Works at Lautenthal, on a steep hillside and ridge.
4°. Works at Ems, on broad, level ground.
In the first case the buildings are long and narrow, following
one another lengthwise in series.
The second case calls for a plant arranged in terraces, the length
of each building being placed approximately on a contour or line
of level of the slope.
In the third case the only systematic arrangement is one which
provides for the automatic descent of the successive products,
while the fourth case offers the most varied opportunities for
the arrangement in plan of the different parts of the works, and
VOL. XV. — 10
138 THE QUARTERLY.
leads to elaborate ore-dressing establishments, of which the plant
at Ems is a conspicuous example.
The movement of the products within the works likewise de-
pends upon the site. On level ground it is necessary to resort to
mechanical devices for elevating and transferring the material,
whereas a sloping site permits the use of gravity for these pur-
poses. Gravity, however, sometimes creates difficulties, notably,
for example, at the Friedrichssegen works, where the steep slope
of the valley makes it necessary to transfer to an intermediate
level the products passing from one building to the next.
A FRENCH REGENERATIVE GAS FURNACE.
By JOSEPH STRUTHERS.
This furnace has been recently used in the laboratory of the
Department of Metallurgy of the School of Mines, and thinking
that the results obtained might be of interest to the readers of the
Quarterly, I have prepared a brief description of the furnace and
the method of operating it.
As is shown in the illustrations, the furnace consists of a body
part of refractory brick (C). forming a solid ring 2y2 inches in
thickness and 4j^ inches in height, with an outside diameter of
13^ inches. This brick is supported upon a similar brick (D),
12^ inches in height and of greater thickness at the base; through
the upper part of this brick are eight channels for conducting the
gas from the burners to the interior of the furnace.
These bricks (C), and (D), are bound together by a sheet-copper
covering which is strengthened and held in position by heavy
copper bands thus forming a solid furnace body. Through the
lower part of the copper covering holes are cut corresponding to
the eight gas channels in the brick (D), which permit the intro-
duction into the channels of the curved pipes at the end of the
burners. The entire brickwork is supported on a sheet-iron stand
(K), having three legs. Several arms are riveted to this stand to
hold the gas supply pipe (A), of I ^ inches outside diameter, which
surrounds the furnace. This supply pipe has a branch at one
side which serves for connection with the laboratory gas supply by
^ FRENCH REGENERATIVE GAS FURNACE. 139
of a rubber hose. From the top of this circular supply
pipe eight ^-inch Bunscn burners are permanently fixed, having
equal distances between them. Each burner has a stop-cock and
sliding valve to regulate the quantity and quality of the flame. On
the top of each burner is a curved brass pipe (B), fitted bya sliding
socket and having the upper extremity protected by an iron bush-
ing. These pipes connect the burners with the channels in the
The cover is of solid brick, 2 inches thick, suitably encased in
a copper ring, with handles affixed to admit of easy removal.
Through the centre of this cover is a circular opening, I % inches
in diameter, which can be closed by a small fire-brick.
The inner shield (F) is of brick, % inch thick and 6^ inches
in height; it serves to direct the mixture of gas and air in the
state of combustion. The flow of the gases is upward through
the space between the shield and the outer brickwork and then
downward inside of the shield to ihe pipe leading to the chimney.
This shield is directly supported on a heavier piece of brickwork,
(E), of special shape, having the shelf (I), for the support of the
crucible.
The lower part of this brick fits tightly into the sheet-iron pipe
(G), 4 inches in diameter, which conveys the products of combustion
I40 THE QUARTERLY.
to the chimney. The strength of the draft is regulated by a damper
not shown in the illustrations.
The air for the combustion of the gas enters the sheet-iron pipe
(H), through a damper placed at the extremity of the pipe some six
feet away from the body of the furnace. This pipe (H), has a di-
ameter of 6 inches, and surrounds the inner chimney pipe (G).
When the furnace is in operation the inner pipe becomes highly
heated by the gases of combustion and serves to heat the cold air
entering the outer pipe.
In putting the furnace together the lower body (D), is placed on
the support (K.) The hollow cone-shaped brick (E), is then placed
in position, the lower part fitting tightly into the sheet-iron chimney
pipe (G).
The bustle pipe for gas (A), is then placed on the supports and
the curved pipes (B), connect the burners with the ports of the fur-
nace ; when all are connected the pipes and burners are perfectly
solid with the body of the furnace. The shield (F), is then set
firmly in the grooved upper surface of the brickwork (E) ; lastly,
the cover is placed on the top. Each piece of brickwork is tongue-
and-grooved so as to afford as tight a joint as possible. The total
height of furnace from floor to top of cover is 40 inches.
To start the furnace all the burner stop-cpcks are closed and the
bustle pipe for gas (Aj, is connected by a rubber hose to the gas
supply which should be of strong pressure.
One burner is then turned on and the gas lighted from the in-
terior of the furnace; the cover being placed in position, a draft
results, and when this draft is of sufficient strength so that there
is no longer an outward pressure of gas in the furnace, the burner
next to the first one is then turned on, and in like manner all the
burners around the furnace are lighted. To avoid too rapid heat-
ing, and consequent fractuies of bricks from too sudden expansion,
it is well to start with alternate burners only, opening the stop-
cocks little by little. When a uniform temperature is obtained it
can be safely increased by opening all the burners.
To insure complete combustion it is necessary that the draft
should be of sufficient strength to carry all the gases of combustion
up the chimney ; if not, back pressure in the furnace will result
and unburned gas will be forced out from the furnace through the
small cracks between the brickwork. The admission of air must
be of exactly the proper quantity for perfect combustion of the gas.
A FRENCH REGENERATIVE GAS FURNACE. 141
When the interior brickwork of the furnace has become heated to
a high temperature the gas for combustion in passing through the
channels becomes heated by direct contact with the white-hot
brick. The air necessary for combustion is partly heated in its
passage outside of the sheet-iron chimney pipes and its temperature
is further raised by direct contact with the heated brickwork in the
lower body of the furnace. The preheated gas and air unite on
the outside of the shield (F), and the combustion takes place on
the outside and inside of the shield, depending on the adjustment
of the strength of the chimney draft and the supply of gas and air.
to insure good working of the furnace.
M. Lequereux, of Paris, in a private communication, claims ex-
ceptionally good results. He has easily melted palladium, which
has a melting point of 1500° C, and has obtained a temperature
at which platinum becomes pasty.
In the experiments carried on at the School of Mines several
objectionable features presented themselves in the furnace manage-
ment. As previously mentioned, there must be an exact estab-
Hshment of gas and air supply, with chimney draft, and since no
chimney draft is constant it is impossible to eveh approximate ideal
results. The crude damper at the end of the air supply pipe admits
of coarse measurement only, and thus the exact air supply cannot
be obtained. When the adjustment is once regulated for a certain
temperature, the removal of the small plug in the cover so as to
ascertain the condition of the furnace interior destroys the set
relations of gas, air and draft, and when removed it necessitates
readjustment. Should anything happen to the crucible placed on
the support (I), the entire cover must be removed, as the hole in the
cover is too small to work through.
In order to obtain a high temperature the furnace interior must
become thoroughly heated, the bricks showing a red to white heat.
In order to obtain this temperature and not fracture the brickwork
by too sudden an expansion, it is necessary to raise the temperature
very gradually. Good results were obtained only after from three
to four hours steady heating. The temperature then showed 1550®
C., as measured by the thermo-electric pyrometer of M. le Chate-
lier. Above this temperature it was impossible to go, owing to
insufficient pressure of gas.
On account of the thickness of the brickwork it is impossible
142 THE QUARTERLY.
to prevent fractures. The first trial of the furnace was carried on
with great care, a very small supply of gas was used and the tem-
perature was gradually raised for four hours, at the end of which
time the furnace showed a temperature of only 700® C. Precautions
were taken so that the furnace should cool down very gradually.
In spite of which, several small cracks appeared in the brickwork
of the cover and body.
A number of experiments were made as to length of time of
preheating, various adjustments of gas and air supply and chang-
ing drafts. The evidence obtained justifies the above statements.
— Metallurgical Labor atory^SchooL of Mines,^ Columbia College ^Janu-
ary^ 1894.
PROFESSIONAL NOTES.
Standard Methods of Chemical Analysis.
In the September number of the Journal of the American Chemical
Society (xv., 501) Messrs. C. B. Dudley and Pease contribute an article
on this subject, of which the following is an abstract :
Chemists often disagree in their results. What is the truth in any
given case? The best possible analytical skill is necessary, as well as
expeditious methods. These ideas led to the formation of the Com-
mittee on International Standards for analysis, the plan being to have
a standard material, samples of which could be furnished to any one in
doubt as to his methods, manipulation, etc.
Does this completely meet the difficulty ? Is a given analytical pro-
cess true for all varieties of manufactured irons? It leaves out of ac-
count possible differences of condition of the element sought in differ-
ent samples. This point might be met by multiplying standards, but
this complicates matters. Possibly, in some cases, a compensation of
errors might give correct results with the standard sample, and not
with some other sample. The plan of the committee to have a series
of standards can only partially meet the necessities of the case.
The causes of discrepancies are at least four :
1. Lack of uniformity of sample.
2. Impurities or defects in chemicals or apparatus.
3. The chemist.
4. The method.
The first and second are obvious, and need no comment. Under 3
it may be said : The analyst may lack a natural aptitude. He may not
take enough pains. He may be deficient in general knowledge of chem-
istry. He may not have the necessary experience. He may fail to ap-
preciate the method used and the reactions involved. Under 4 it may
be said that the descriptions given may be indefinite or that different
methods laid down may not be quantitative to the same degree of ac-
curacy.
The practical point is, How can discrepancies be prevented ?
In the case of disagreement in results between two chemists, say
those representing the buyer and the seller in a certain transaction, the
causes for discrepancy may be met thus :
1. Exchange of samples.
2. Exchange or test of chemicals.
3. Have the chemists work in presence of each other.
4. Since application to standard samples may be defective, it would
be preferable to establish a standard method.
The arguments against, and comments upon such a procedure are :
Suppose no method can be found which is generally regarded as sat-
isfactory? The reply is : Accept the best one known temporarily.
Such establishing of a standard method would be a bar to progress,
144 THE QUARTERLY.
there still exists a stimulus for criticizing the methods prescribed with a
view to improving the same.
What is the sphere of a standard method ?
Analyses are made for different purposes They may be:
1. For guidance in the management of a plant. Here speed is most
important.
2. For commercial transactions. This requires speed 2iXiA accuracy.
3. For investigation. Here accuracy is chiefly important.
The requirements in the second (commercial transactions) seems to be
the most desirable for a standard method.
P'inally, what features are indispensable for a standard method?
1. It must be sufficiently accurate. No method is absolutely 2siQMX2Xt.
By a standard method three or four results, in the hands of as many good
and experienced chemists should agree, thus :
Per cent.
For C, wilhin 0,01
** P, * 0.005
*« S. ** 0.005
** Si ** o.oi
" Mn, ** O.OI
" Cu, ** 0.005
2. It should be sufficiently rapid. If the sample is received in the
morning, results should be obtained the same day.
' 3. It must be simple, />., the manipulations should be such as to allow
an analyst to do more than two or three analyses in a working day.
4. The conditions should be well studied out.
5. Different chemists should be able to obtain concordant results.
A circular has been issued regarding the International Congress of
Applied Chemistry, to be held at Brussels, on August 4, 1894, which is
promoted by the Belgian Association of Chemists, and is under the pat-
ronage of the Belgian government.
The body of the circular contains the following (C.N. Ixviii., 302) :
" The science and practice of chemical analysis plays such an im-
portant part in the commercial side of industrial and agricultural chem-
istry, both in the control of manufactures themselves and in the solu-
tion of hygienic problems, etc., that it becomes more and more im-
portant that there should be greater agreement and accord between the
various methods of analysis now in vogue among analytical chemists.
That there should be so much disagreement between the results obtained
from different laboratories is greatly to be regretted, but these disagree-
ments (when they occur) are more often caused by the employment of
different methods than by any want of skill or care on the part of the
operators. To remedy this state of things the Organizing Committee of
the Congress considers that it is indispensable that there should be a
unification of methods of analysis, not only in each country but uni-
versally, and that the standard processes to be adopted should be de-
cided by international agreement. It is in the endeavor to solve the
inevitable difficulties of such a scheme that the proposed Congress has
been convened."
PROFESSIONAL NOTES. 145
The Congress will be divided into four sections :
A. Sugar Imfusirifs. — Ten heads — Water in sugar, Molasses, Color,
etc.
B. Agricultural Chemistry. — Nine heads — Nitrogen, Saltpetre, Milk,
etc.
C. Food Products and Public Health, — 5 heads, — Butter, Liquors,
Potable Waters, etc.
D. Chemical Biology^ — 7 heads. — Brewing, Vinegar, Distilling, etc.
That the adoption of uniform methods of analysis is a necessity of
the present condition of chemical industries, is fully shown by the
above. In addition might be mentioned the International Committee
on Standards for the Iron and Steel industry, and the work of the Asso-
ciation of Official Agricultural Chemists. Many suggestions in the same
direction have been made in our learned societies, bnt as a rule they
have been looked upon somewhat askance, as tending to commit those
bodies to something like this : ** Perfection has been attained (in this or
that) and no further progress is possible." This may be an extreme
statement, but that is what many fear. Of course such a position is un-
tenable, but if the subject is taken up in a spirit of co-operation, an
agreement to accept the best known methods, and to strive earnestly
together to improve upon that, much energy now wasted, will be utilized
to the advantage of both theoretical and practical workers in the field of
chemistry.
The limits set by Dr. Dudley for accuracy to be required, seem to be
at present unattainable, though it is desirable that they should be aimed
at. Witness a comparison with the maximum differences of results
among the members of the American, English and Swedish commission
on International Standards.
Proposed Limits. Differences.
Dudley d. Pease. International Standard.
C, o.oi 0.048
Si O.OI 0.017
S, 0.005 0.009
P, ........ 0.005 0.024
Mn, O.OI 0.032
Detection and Measurement of F ire-Damp.
M. Chesneau read a paper before the International Engineering Con-
gress (published in the Transactions of Am, Inst, Min. Eng.) on this
subject, which contains many points of interest. He deals with laboratory
methods. Uuder this are described :
1. Determination by combustion. Coquillon's apparatus — the same
modified by Poussigue, and Le Chatelier's apparatus.
2. Determination by limits of combustibility. At teniperatures be-
tween 10^ and 20° C, air mixed with 8 per cent, of illuminating gas or
with 6 per cent, of methane, becomes explosive. To determine the
proportion of fire-damp then, it is sufficient to add either illuminating
gas or methane until the mixture becomes explosive. By two or three
trials, it may be decided how much fire-damp the air originally con-
tained. This is the principle of Shaw's indicator which is described as
is also a simplified form devised by Le Chatelier.
146 THE QUARTERLY.
Next are considered portable indicators for underground use. Under
this come :
1. Indicators based on the physical properties of fire-damp. Diffu-
sion, sound vibrations, etc. (Ansell, Forbes).
2. Thermo electric effect-heating of a pjatium wire through which an
electric current is passing, by the presence of fire-damp in the surround-
ing atmosphere (Liveing, Murday).
3. Elongation of a lamp flame (Chesneau),
4. Flame aureoles. Lamps devised by Mue.^eler, Pieler, Wolfe,
Clowes, Legrand, Dinoire, Marsand and Chesneau.
The flames of hydrogen or of alcohol give more decided indication
than that of oil, and in most of these lamps some substance, as hydro-
gen, alcohol, or naphtha, lighter than^oil, is used for the tests. All re-
ceive some description, but the lamp devised by the author (the Ches-
neau lamp) is more particularly described. The strength of the alcohol
used is an important point which has frequently been overlooked in the
use of lamps of this class. The use of a little CuCl, in the alcohol
burned, has been adopted, because rendering the aureoles more clear.
It necessitates, however, the changing of the wick before each tour of
inspection.
ABSTRACTS.
The separation of heavy minerals by reason of their different specific
gravities has always been attended with more or less difficuliy.
To separate minerals whose specific gravity is above 3.65, which is
the limit for heavy liquid, fused zinc, tin, or silver, salts have been used.
This is more or less unsatisfartpry and inaccurate.
FIC. £
The following apparatus is intended to eflecta sorting by means of an
upward current of water. It should perhaps be called an apparatus of
"concentration" rather than "separation." The parts are 1 The
pressure regulator (Fig, i), consisting of a Wolff flask of two litres
capacity, and which when in use is placed two metres above the work
table ; f is 3 mm. diameter and connects with the separator by means of
148
THE QUARTERLY.
a rubber tube ; /? is 3 mm. diameter and connects with the water faucet.
The overflow, b^ is 10 mm. diameter.
Fig. 2 is the separator. It consists of an outer tube, I a h, and the
draw tube, b. The liquid comes in at <7, flows downward, and enters
the inner tube aty! It then flows upward in the space ^as far as /, and
escapes by the tube, h. The opening at / should be very small and can
be regulated by the rubber cord. <r.
Around the tube is a spiral of ^ mm. platinum wire, whose coils have
a diameter of 5 mm. Its object is to divert the course of any counter-
currents which may arise, and direct them upwards.
Two cocks are placed between the regulator and separator. «, Fig. 3,
is an ordinary cock^ and ^, Fig. 3, a *' precision cock." Figs. 3 and 4
explain its construction.
\
L
I
nar
/ \
s
In Fig. 3 the diameter of b and cocks is 4 mm. Fig. 2, a, diameter
4 mm.,/ 10 mm. ; g^ 7 mm.; b, 3 mm. ; height of/, 140 mm. ; ^, 330
mm. ; ^,520 mm, to /, 280 mm.
The following precautions must be borne in mind to insure approxi-
mately accurate separation :
The grains should be of same size, and similar form. This is a weak
point of the process.
The material should be constantly in the path of the current.
The current should be of uniform velocity, and as weak as practica-
ble. Practice has shown that the density of the liquid employed has
little or no effect.
Manipulation. — Open the stop cock, a (Fig. 3), and close tube h
(Fig. 2), with pinchcock. Allow water to enter tube until it reaches the
level /. Shut ofl"the water. Introduce the mineral at /. Two grammes
is the usual charge. Open tube, //, so that level of water falls to /. Turn
ABSTRACTS.
149
on water slowly to start the mass which has settled to the bottom of the
tube, slowly in motion. The current is regulated to bring the mass to /.
The light and heavy materials gradually separate.
The light sand is removed by lowering the tube, d, gradually until its
top is level with the same. ,
If the heavier portion of a mixture is to be separated alone a jigging
movement of the current, will tend tD wash both the lighter and
tnedium weight grains into the tube, b.
With a fine adjustment of the current and a repetition of the process
on the heavier portion, a nearly perfect separation may be obtained.
Results. — To test the process, the heavy residue from a decomposed
TOUscoviie granite was passed once through the apparatus, withdrawn in
two portions, and the different minerals completely separated under the
lens and weighed. The sand was prepared by passing through a Thoulet
solution, partially cleaned of iron minerals with magnet, and screened
between bolting cloth, Nos. i and 4.
The residue contained chiefly titaniferous iron, manganite and xeno-
time with a few grains of staurolite, tournialine and niuscovite, the total
quantity being 1.77 grammes. The following table gives percentages
of the three principal minerals in the lighter (I.) and heavier (II.)
portions ; and those of the total amount of the mineral in each two
portions.
1
Original
€> 1
Perct. toTy.
P.r ct. to Tt.
Pan 1.
Part II.
Sample
Per cent.
Total in I.
Total in II.
Per cent.
Per cent.
Xenotime ;
i
(Sp. gr., 4.45 -^)..-
18.50
26.5
6.3
86.5
'3.5
Menaccanite :
i
(-''P gr., 4-75 -^^•••
31.9s
45.0
12. 1
84.9
I5.I
Monazite :
!
(Sp. gr„5-f-)
49. CO
28.5
81.6
; 34.4
65.3
In another test 3 grammes of the same residue were screened between
Nos. 4 and 5 bolting cloth and withdrawn in three portions; light (I.),
medium (II.) and heavy (III.) as follows:
1
Original
1
I.
II.
HI.
Tv
1 in I.
Tr
in II.
7v
in HI.
Per ct.
23.6
Per ct.
Per ct.
Per ct.
II. 8
Per ct.
7.5
Per ci.
Per ct.
Xenotime
36.7
42.2
62.3
30.2
Menaccan ite
'9.5 1
56.9 '
1
'4.4
48.9
24.4
II. 9
76.3
3.5
4.'
59.5
15.0
37.0
80.9
Monazite
These results are considered good, as they were made in an im-
150 THE QUARTERLY.
provised experimental apparatus. The sand used was a difficult one to
sort, as the grains were of very variable size and shape.
Abstracted from a "paper **On the separation of minerals of high
specific gravity/' by E. W. Dafert, and O. A. Derby, Proc. Rock. Acad,
Sa\, Vol. II. H. RiES.
Analytical Chemistry, by E. Waller, Ph.D.
Filtration, Land is {Jour. Anu Chem. Soc,y xv., 480), notes that by
using a ground glass funntl^ the filter paper may be made to stick so
tightly to the glass, that no danger of loss occurs in washing the upper
edge of the filter.
Indicators in Sulphide Titrations . Williams (CiV., Ixviii., 236). Nitro-
prusside indicates 0.0000982 gramme of Na^S in i c.c. of water, while
lead acetate in NaOH indicates 0.0000245 gramme of Na^S in i c.c.
Alkalinity of Liquids Containing Chlorine, Ullmann {Chem, Zeit.^
xvii., 1208) finds that succinic acid decomposes hypochlorites (and car-
bonates) but not chlorides. If, therefore, a known amount (excess) of
succinic acid is added, and the solution boiled, it may be titrated back
with standard alkali, using phenolphthalein as indicator. A determina-
tion of available chlorine (and consequently of HCIO) gives a basis for
calculation of the alkalinity. (The result in case chlorate is present is
not stated. — Abs.).
Separation of Caesium, Wells (^Am,J. Sci , xlvi., 186). Cs^PbCl^ is
practically insoluble in a PbCl, solution in HCl saturated with CI, the
corresponding Rb salt being more soluble. The formation of this com-
pound affords a means of separating Cs completely from other alkali
metals, and partially from Rb.
Chromium Determination, Spuller and Kalman {Chem. Ztg^, xvii.,
141 2). Fusion with caustic soda and Na,0, is not well adapted for
decomposition of hardened chrome steel, but it is applicable to ferro-
chrome, and to chromite. Ferro-silicon and ferro-tungsten may also be
decomposed by this method.
Microchemical Detection of Iron, Lemberg {Z. Dent, Geol, Gesell ^
xliv., 823}. Addition of (NHJ^S to a granule of soluble substance on a
microscope slide — black — FeS. The formation of a black sulphide is,
however, not distinctive for Fe, On removing the excess of (NH^),S,
and adding a drop of concentrated aqueous solution of potassium ferri-
cyanide the black FeS is convened to Turnbull blue in about 8 minutes.
Manganese in Manganese Bronze. Jones {four. Am. Chem, Soc.^ xv.,
414). Dissolve 5 to 10 grammes in HNO3 (Gr. 1.2). Place in a cylinder,
dilute to 300 c.c, and pass H,S until the supernatant liquid is colorless.
Decant off through a dry filter 180 c.c. or some aliquot part, boil this
down to 10 c»c., add 25 c.c. HNOg, boil down, precipitate Mn by KCIO,,
and conduct the rest of the operation as in the Ford- Williams process
for Mn in manufactured irons.
ABSTRACTS. 151
Deieciing Iron in Copper Sulphate, Griggi (JSoll. Chim. Farm,, xxxii.,
549). Introduce a solution of the commercial sample into a test-tube,
pour on top of this an ether solution of salicylic acid (1 in 10). If Fe
is present the violet color appears at the junction of the two fluids.
Reducing Iron for Titration, Storch ( Ber, d, (Esterr, Ges.y etc., xv.,
9") advises the use of metallic Cu, previously washed with alcohol and
ether and then with water. On warming the reduction occurs readily.
At the end-reaction the-color changes from greenish-blue to violet.
Dichromate Titration of Iron, Mahon (^Am. Chem, Jour.^ xv., 578)
notes the following facts : When iron ores are brought into solution by
fusion with alkaline carbonates in a platinum crucible, and subsequent
solution in HCl, some Pt may be attacked by the flux and thus brought
into the solution. In that case, when the titration of the iron is reached,
the SnClj first reduces the Fe, and afterward the PtCl^ to PtCl, giving
first a colorless solution, and afterward a colored one. On titrating,
some error is thus introduced. If the amount of SnCl, added is so
regulated that the addition is stopped when a colorless solution is first
obtained, the diflftculty may be avoided.
Nickel Determinations, Sleeper (C N.y Ixix., 15) gives very minute
directions regarding the method which he pursues, which consists in
obtaining an HCl solution of the material containing 8 to 10 per cent,
of free acid, precipitating with H^S, boiling out the H^S, precipitating
Ni and Fe by NaOH, in excess, dissolving this in H,SO^, and from this
solution precipitating Fej(OH), by excess of ammonia poured rapidly
into the ^£7/// solution. This operation may have to be repeated two or
three times, when the solution is concentrated to convenient bulk and
electrolyzed, ammonia being added from time to time.
Colorimetric for Uranium, Bruttini (Gazetta, xxiii., 251). The depth
of tint obtained by addition of K^FeCy^to HNO, solution of the uranium
forms the basis of this method. A description of the method of separa-
ting from interfering elements is given.
Standard Solutions of Tartar Emetic, Gruener (^Am. Jour. Sci., xlvi.,
206). Solutions containing 36 grammes of tartar emetic per litre, will
keep well for 5 or 6 months if containing 20 to 30 grammes tartaric
acid or i c.c. of HCl per litre. No oxidation of the Sb was noted in
any case, though with some of the solutions tried, a fungous growth
formed in the solutions.
Separation of Metals in the form of sulphides by heating in a stream
of bromine vapor. Etz {Berichte,, xxiv., 76, and xxv., 124). On heating
the dried sulphides in a current of air loaded with Br., BiBr, may be
readily volatilized by applying a gentle heat leaving CdBr, or PbBr,
behind. SnBr^ can also be separated in the same manner. The sul-
phides if prepared by precipitation must be quickly and thoroughly
dried. Protracted exposure to air causes partial failure. With Wood's
alloy and others, it is best to convert to sulphides by heating the chip-
pings of the alloy mixed with pulverized sulphur in a porcelain boat
surrounded by an atmosphere of CO, until the conversion to sulphide is
153 THE QUARTERLY.
effected, when the most of the excess of S may be volatilized off, and
then passing Br vapors. The presence of a little excess of S does no
harm.
Separating Cadmium from Copper, Browning {Am,/.Sci.^ xlvi., 280).
The metals being in the form of sulphates, KI in slight excess is added,
and. the solution is then evaporated to dryness to expel free I. On taking
up with water, CuJ, remains insoluble, and may be filtered off through
asbestos, dried at 120 to 150° C. and weighed. . In the filiraie Cd may
be precipitated by Na,COj„ ignited to CdO and weighed. In presence of
KI, H,S gives precipitates of Cd that cannot conveniently be filtered.
Volumetric for Lead, Laune ( C, iV., Ixviii., 211). The author has en-
deavored to render the bichromate titration m?re satisfactory. He finds
it well to have in the solution the equivalent of 0.2 to 0.5 ;^ramme NaCl
per 100 c.c. The bichromate solution used was of the strength i c.c.
0.002 gramme Pb. Large quantities of salts in the solution are inad-
missible. Any acidity must be neutralized, and NaCjHjO^ must be added.
To get a sharp end- reaction, it is advised to add nearly enough bichro-
mate, and then heat to boiling. The precipitate then settles readily, and
a drop or two of the clear solution may be taken out for th*^ ** spot test **
with AgNO, solution. (Red precipitate when excess of chromate.)
Analyses of Galena, Lindemann and Motteu {Bull, Soe, Chim.^
ix., 812), 0.5 to I gramme of the ore is triturated in an agate mortar with
solution of chloride of lime, added in small quantities at a time, until
and after complete oxidation of the ore by this means, the material is
transferred to a beaker, solution of chloride of lime added in quantity
sufficient to precipitate all the lead as PbO,. After washing by decan-
tation, 25 c.c. of a 50 per cent, solution of KI is added, then 30 c.c. of
20 per cent. HCl, and the I set free is titrated with standard Na^S^O,,
the solution being made up to 150 to 200 c.c. In case of the presence
of Fe or Cu, the solution obtained by action of the chloride of lime, is
evaporated to expel CI etc., the Pb precipitated by H,S, and the PbS
treated as above. CuS, if mingled with the PbS is removed by KCy,
before converting the lead to PbO,.
Separating Lead and Copper, Jannasch and Lesinsky {Berich/e,,
xxvi., 2331). The solution of the metals in HNO,, in a bulk of about
60 c.c. is mixed in the cold with 60 c.c. of (at least 2 per cent.) H^O^
solution, and excess of ammonia. After adding 50 c.c. of saturated
solution of (NHjjCOj the PbOj (hydrated) is filtered off and washed,
first with ammoniacal H.^0, solution, afterward with ammonia only.
There is some tendency tor the Cu to remain in the precipitate. The
PbO, is converted first to nitrate then to PbO in which form it is
weighed.
The Cu in the filtrate is separated by H.^S, ignited, and finally weighed
as CuO, fumes of (NH^^COg being brought in contact with it in such
a way as to remove all sulphate.
A large excess of H/)., gives with Pb silts white nacreous leaflets com-
pletely insoluble in water and ammonia. It may be separated in a
similar manner from Z\\ and from Ni.
ABSTRACTS. 153
Qualitative Analysis by Electrolysis. Kohn (C iV., Ixviii., 188).
The paper may be summarized as follows :
lemcnt.
SK, . .
Hg.. . .
Pb., . .
Cu., . .
Solution
used.
HNOs
. HNOj, 10 to 20 per
. KCy or KjC^O^
cent.
( urrent
per min.
1 5 to 2 C.C
4 to 5 C.C.
2 to 3 C.C.
Delicacy
z part in,
\)^ million.
i»
<<
3 million.
\)^ million.
■— ' — * 9 «
Cd, . .
0.2 C.C..
The tests are much more delicate than with H,S. In testing urine or
other organic liquids twice as much time must be allowed as when the
solutions contain only mineral salts alone. For lead in organic solu-
tions, the addition of (NH^'^jCjO^ is necessary.
Electrolytic Separations , Vortmann (^Monatsh, f. Chem.. xiv., 536).
The apparatus is figured and described. Alkaline solutions are used.
Zn is readily precipitated from NaOH and Rochelle salt solution on a
silvered copper dish. Strength of current per 10 cm* 0.3 to 0.6 ampere,
Fe separates well as an adherent coating to Pt or Ag in an alkaline
tartrate solution containing free alkali. The coat contains only minute
antounts of C after long action.
Co requires the presence of KI. The NaOH must be so strong that
the solution is blue in the cold. The anode is always coaled with an
adherent slime which contains traces of Co.
Ni is precipitated under conditions similar to Fe with a moderately
strong current.
To separate Zn in presence of Ni, add Rochelle salt and conr. NaOH
and then electrolyze. Fe in presence of Ni in a similar manner, but
not quite so satisfactorily. Co may be separated from Ni.
To separate Fe and Zn add tartrate, render alkaline and electrolyze
in Pb. which affords the Fe, (with traces of Zn) then transfer to a
silvered dish and preripitate Zn. For complete separation redissolve
the Fe and repeat. Or else use an alkaline solution containing KCy
from which Zn is precipitated and Fe remains as K^FeCy^. To sepa-
rate Co and Ni from Fe, oxidize with Br water, add (NH).^SO^ and
ammonia and electrolyze. The Fe/OH), may remain suspended in
the solution.
To separate Cu in presence cf much Fe, oxidize with HNOj, and con-
duct the operation as in the separation of Ni and Co.
Electrolytic Separation of Lead from Copper. Nissenson (Z/j. Angew.
Chem,^ 1893, 646). The separation can be completely effected if pro-
per conditions as to strength of current, and amount of acid are estab-
lished ; I gramme of the ore is dissolved in 30 c.c. HNO3 (^^- ^-4) ^'"
luted to 180 C.C. and then electrolyzed, beginning with a current of 0.5
ampere, and after an hour increasing to 1.5 to 2 amperes. The separa-
tion is complete in 6 to 7 hours.
Estimating Free Chlorine. Fried heim {Zis. Anorg, Chem., iv., 145).
If the CI absorbed in Na^CO, and to this solution KI is added, and the
titration performed with standard Na^SjO^,, the results are always low.
VOL. XV.— II
154 THE QUARTERLY.
The reason assigned is that some sulphate is formed in the alkaline sohi-
tion by interaction of [ and Na^SjOj. If however the Na^CO, sohition
in which the CI has been absorbed, is mixed with a KI solution con-
taining excess of H^SO^, the titration results are correct.
Chlorine Titration, Fairley {Analyst^ xviii., 222). The presence of
even small amounts of alkaline silicates appeared to interfere seriously
with the accuracy of the titration for chlorides (standard AgNO, with
KjCrO^ indicator).
Sulphur in Py rites, Ferguson ( Oil^ Paint and Drug Reporter^ Nov.
1893, p. 10), describes the Br method as used in the laboratory of the
Nichols' Chemical Co. Br solution. Treat 75 grammes KBr with 50
c.c. HjO. When nearly dissolved, add 50 c.c. Br. Stir until nearly
dissolved, transfer to 500 c.c, stoppered flask, add a little water, shake
gently, finally All to 500 c.c. and shake until dissolved.
Analysis. Add 20 c.c. Br solution to 1 gramme of pulverized sample
in a covered litre beaker, mix well and let stand cold ten minutes, then
add 10 c.c. HNO,, mix and let stand ten minutes more cold. Place on
a .steam bath, and when the solution becomes quiet, rinse off the cover,
and evaporate to dryness; add 10 c.c. HCl, and cover until violent
action ceases, then remove cover, and evaporate to dryness again. Take
up with 20 c.c. HCl in 100 c.c. hot water, stand 10 minutes ; filter and
wash thoroughly three times. Test the residue for sulphides. If they
are present the operation must be repeated on a fresh lot of material.
Heat filtrate on a steam bath, and add 35 c.c. BaCl, solution (1 : 10),
from a burette drop by drop, stirring briskly, let stand one hour on the
steam bath filter, wash etc. and weigh BaSO^, add 0.2 per cent, for
solvent effect of hot acid Fe^Cl, solution. Duplicates on 22 analyses
show an average difference of 0.15 per cent. ; analysis of 27 samples by
Br method compared with results by fusion method (mixed alkaline
nitrates and carbonates) showed the average results to be the same for
both. The Br method is more expeditious than the fusion method, and
requires less personal attention.
Sulphur in Manufactured Irons, etc. Hooper (C -.V., Iviii., 191).
The element is evolved as H,S (by boiling 5 grammes with HCl) and
the gas passed into 10 c.c. Na()H solution (Sp. Gr. 1.20). When
solution has been effected, the NaOH solution is rinsed into a larger
breaker, and standard solution of Pb (NO3), run in, until no more
brown coloration occurs. The standard lead solution contains 3.2265
grammes Pb dissolved in HNO, and diluted to one litre, i c.c. o 0005
gramme S.
Barium Sulphate Precipitate. Phinney {Am. J. Sci. xlv., 468).
Contamination by alkaline chlorides can only be removed by fusing
with NajjCO,, and reprecipitating (Fresenius) or dissolving in strong
H,SO^ and evaporating (Mar). The use of aGooch filter with asbestos
bed is preferable to avoid reduction to BaS on ignition.
Volumetric for Phosphoric Acid. Holleman (^Rec. Trav. Chem., xii.,
i\ 50 c.c. of the solution, containing not over 0.2 gramme PjO^,
ABSTRACTS. 155
slight excess of tenth normal AgNO,, and it is then nearly neutralized
with tenth normal soda. After dihiting and filtering off AgjPO^, the
excess of Ag remaining in solution is determined by Volhard's method.
JDetermining Phosphoric Acid. Pemberton {J, Am, Chem. Soc.^ xv.,
382). claims priority in the method by acidimetric titration of the
yellow precipitate (^Jour. Frank, ///i-/., cxiii., 193., C. yV., xlvi., 7).
Some references to the literature of this method are given : Thilo
{Chem. Z/^., xi.. 193) ; Hundeshagen {Zts, AnaL Chem.^ xxviii., 171);
Manby {J, AnaL and App, Chem.y y'x., 82); Handy (7^, vi., 204);
Rothberg and Auchinvole (7^., vi., 243). The solutions used are:
(NH*)^ MoO^, 90 grammes of crystals in one litre, no nitric acid;
NH4NO, saturated solution ; Standard KOH, 100 c.c. = 32.65 c.c.
normal acid ; i c.c. = o.ooi gramme P^Oj ; Standard acid, of corres-
ponding strength. (These may be made by diluting 326.5 c.c. of
normal acid or alkali, each, to one litre.); Indicator i gramme phen-
olphthalein dissolved in 100 c.c. of 60 per cent, alcohol (use 0.5 c.c.
for each test). The standard alkali must contain no carbonate.
Method, Dissolve i gramme of phosphate rock, or 2 to 3 grammes of
fertilizer in HNO,, and without evaporating or filtering, dilute to
250 c.c. Draw off 25 c.c, neutralize it with ammonia, and then add
5 c.c. HNO, (Gr. 1.4). Then add 10 c.c. of the NH^NO, solution,
and dilute to 50 or 75 c.c, bring to a full boil and after removing from
the heat, add 5 c.c of the (NH^), MoO^ solution. Follow by a second
or third 5 c. c of the reagent, as may be found necessary. Let settle,
and wash with water by decantation and on the filter. (G?/// water is
not specified, but would probably be advisable. — Abs.) Transfer the
precipitate and paper bodily to the beaker. Run in measured excess
of standard alkali, add 0.5 c.c. phenolphthalein solution, and titrate
back with the standard acid.
Ammoniutn-Magnesium Phosphate, Neubauer (Z/f. Anorg, Ch., iv.,
251), asserts that errors may result ; when no excess of Mg salt is present ;
in that case the precipitate contains two little Mg and some P^O^ is lost
on igniting. When decided excess of ammonia is present ; in this
case, more MgO than suffices to form MgNH^PO^ comes down with the
precipitate, giving too high results. Obtaining exactly correct conditions
in all cases is manifestly impossible. The method recommended is the
use of solutions containing 2^ per cent, of ammonia. The magne-
sium mixture (55 grammes MgCl,, 70 grammes NH^Cl in i litre of
2j4 per cent, ammonia) is added slowly (at the rate of about 10 c.c.
in a minute) the dilute phosphate solution being continually stirred
during the addition, with a final vigorous stir after a small excess has
been added. After standing cold at least three hours, it is filtered and
washed (with 2^ per cent ammonia) and after transferring to a weighed
crucible dried, and gradually heated to ignition, never allowing the
temperature to pass a moderate red heat so long as any carbon re-
mains. A correction for loss must always be applied, for which a
table is given.
Carbon in Steely etc. Proposed Standard Method. Dudley and
IS6 THE QUARTERLY.
Pease {/our. Am. Chem, Soc, xv., 526), Treat 3 grammes of the
sample with 200 c. c. of an acid solution of CiiCl,, 2KCI, at a tempera-
ture not above 100°. Agitate during solution. When Cu is all
dissolved, decartt through an asbestos filter in a platinum boat. Rinse
into the filter with dilute HCl (Gr. i.i) and wash with this acid until
the washings are colorless, then wash with water. Dry at not over
212° F., and subject to combustion in a porcelain tube in a current of
oxygen. This gas is first passed through a ** preheating '* furnace — a
porcelain tube about 20 inches long filled with granulated CuO, and set
in a combustion furnace; next through a purifying bulb. (Geissler
charged with KOH solution), then into the combustion tube containing
the carbon. Next to the boat in the tube comes a roll of silver foil,
then 4j^ inches of Cu gauze then granulated CuO, then more Cu gauze,
and an asbestos plug. Beyond the combustion tube is a bubble tube
containing acid FeSO, solution), next a bubble tube containing saturated
AgjSO^ solution, next a CaCl^ drying tube, and next the absorption
bulbs (Geissler form preferred) charged with KOH solution with pro-
long containing granular CaCI,. The two last are weighed before and
after the operation. Bevond these is a CaCI, bottle and an aspirator.
Special directions are given for preparation of the reagents, stirring
apparatus, regulating the combustion, etc.
Carbon in SieeL Drown, in a letter to the committee on Interna-
tional Standards, report some experiments on dissolving steels in copper
salts. CuCU acidified with 20 per cent. HCl dissolves the iron with
reasonable promptness. 40 per cent, of HCl is apt to cause loss. The
addition of alkaline chloride however, facilitates the solution. Good
results were obtained by using to 3 grammes of steel, a solution con-
taining 12 grammes Cu (as CuCI,) 15 c. c. HCl (Gr. 1.2) and 60 c. c.
NaCl solution (320 grammes per litre).
Analysis of Carborundum. Mulhaiiser {^Zts.f. Angew. Chem,^ '^93
P- 637). — Grind up repeatedly in an agate motar, and elutriate. The
material remaining in suspension in water after five minutes, is taken
for analysis. For C mix with PbCrO, alone^ and subject to combustion.
For Si, mix with KNaCO, and fuse.
Analysis of Silicates. Gluika (y. Russ, Chem. Sac, xxiv., 456),
prefers Deville's method, especially for feldspars. — Mixing with an equal
weight of pure (specially prepared) CaCO, and heating up — finally
bringing it to fusion, which is maintained for 10 to 15 minutes. After
cooling the melt may be dissolved in HCl or HNOj, and the analysis
conducted as usual, for SiO,, Al,Oj alkalies, etc.
Estimating Chlorates^ Nitrates and Nitrites, Roberts (^Am. Jour, Sci.,
xlvi., Sept.). Boiling a solution of nitrate (acidified with HCl) with
MnClj affords CI which when passed into Kl solution may be estimated.
The NO evolved may also be measured over NaOH solution. FeCI,
with measurement of the NO may also be used. Solution of chlorate
also gives a proportional evolution of CI which may be passed into KI
and estimated by titration with standard thio-sulphate. In a mixture
of nitrate and chlorate, both may be determined in one operation with
ABSTRACTS. 157
MnCl, by measuring the NO evolved. Then on titrating the I set free,
and allowing for the amount attributable to the nitrate, the remainder
is due to the chlorate present. If a mixture of nitrate and nitrite i^
tested, a calculation from the I set free and the NO obtained, will afford
a means for calculating the proportion of each present. A special form
of apparatus is recommended, in which all the air present must be
driven out by CO^, before beginning the operation, a precaution espe-
cially, necessary when nitrite is present. The results are fair in case
nitrite is present.
WaUr Analysis, — Use of Na,0,. Rideal and Bult (C N.^ Ixviii.,
190). Used as a substitute for alkaline permanganate the Na,0, in no
case oxidized the nitrogenous organic matter to the same extent, though
it gave constant results with the same water. The suggestion is made,
that by the use of this reagent a differentiation between different classes
of nitrogenous organic matter may be effected.
Preparation of Potassium lodate. Gorget (Z/j. Angew, Chem,^ 1894,
13). Dissolve 40 grammes pure KgMn^Og in a litre of hot water, add 20
grammes KI dissolved in a little water, heat over a boiling waterbath
for 20 to 30 minutes, and then add alcohol drop, by drop, until the
liquid is decolorized. Filter, and wash the precipitate with hot water.
Then acidify with acetic acid, evaporate to 50 c.c, cool and allow to
crystallize, and then wash the crystals repeatedly with strong alcohol
and dry. The yield is 90 to 95 per cent, of the theoretical amount in-
dicated by KI + K,Mn,Og + H,0 = KIO3 + 2KOII -f- 2MnO,.
If acetic acid is not used, much loss may be experienced in attempt-
ing to wash adhering alkali from the crystals.
International Standards for t/u Analysis of Iron and Steel. Report
of the Committee. The results were :
Mean (American).
^^^ No... No^ No. 3. No. 4.
C, 1.44 0.807 <>-452 0.18
Si, 0270 0202 0152 0015
S, 0.004 0.004 0.004 0.038
P, 0.016 o.oio 0.015 0.088
Mn, 0.254 0.124 0.140 0.098
Afean (English).
C 1.414 0.816 0.476 0.151
Si, 0.263 0.191 0.141 0.008
S (not over), . . . 0.006 0007 0.008 0.039
P, 0018 0.014 0.021 0.078
Md, 0.259 0.141 0.145 0.130
Mean (Sioedish),
C, 1.45 0.84 0.50 0.17
Si,
S, .
Mn, .
0.257 0.185 ^-^S 0.015
0.008 0.004 0.006 0.048
0.022 0.015 0.021 0.102
0.282 o 145 017 o 13
BOOK REVIEWS.
Rksistance of Shpi»s and Screw Propulsion. By D. W. Taylor, Naval Con-
structor, United States Navy. 8vo. Pp. ix. aixl 234. Macmillan & Co , New
York and London, 1893.
For more than a hundred years the principles of hydromechanics have
been a subject of elaborate investigation by the ablest mathematicians.
Some af the nwst profound memoirs in mathematical literature were de-
voted to these principles, and a large body of scientific doctrine has
been permanently acquired. Nevertheless, it must be said that com-
paratively little progress has been made toward a satisfactory theoretical
solution of such apparently simple problems as tlie resistance encoun-
tered by ships in water or projectiles in air. In the meantime, however,
experimental science has made great progress in the collection of facts
relating to such problems and in the perfection of appliances subject to
hydrodynamic conditions. Various methods and devices have been
perfected to facilitate the study and discussion of the special cases into
which a general problem divides itself; and a skilled experimentalist
will undertake to determine the characteristic properties of a water
motor, a steam engine or a steamship working under any clearly defined
circumstances. Not the least useful feature of Constructor Taylor's
book arises from the fact that it calls attention repeatedly to this dis-
parity between the data afforded by a modern steamship, for example,
and the means supplied by theoretical mechanics for the interpretation
of such data.
The work is intended primarily for that small class of readers called
naval architects. The preface states that "in his professional work the
writer has often felt the need of a short treatise upon the resistance and
propulsion of ships.'' .... ** The writer has endeavored throughout to
discuss ships as they are, not floating bodies in general ; to set forth
methods and deduce results as simple as the nature of the subject will
allow, and sufficiently accurate for everyday use/* Though thus de-
signed for specialists, the work contains much of interest to all students
of hydromechanical questions. The six chapters of the book are de-
voted to Resistance, The Propeller, Mutual Reactions between Propeller
and Ship, Analysis of Trials and Average Results, The Power of Ships,
and Propeller Design respectively. Supplementary to these are Tables
I. -XX., giving various numerical data pertaining to the subjects treated.
The style of the author is that of the practical man rather than that of
the investigator, and the results he reaches cannot be considered ahead
of the limes. But his intention was evidently to write for practical
men, and to such the work will no doubt prove very useful. R. S. VV.
The Mkchank-^ of Hoisting Machinery. Weisbach & Herrmann. Translated
by Karl P. Dahlstrom, M E. 1893. Macmillan & Co. 8vo. 329 pp. $3.50. This treatise forms a contribution to a series which has been com- pleted by Messrs. Coxe, DuRois and Klein, and which has covered the immense undertaking of Dr. Weisbach upon theoretical mechanics, hy- draulic and steam engines, and the machinery of transmission. It con- cerns itself with that department of industry so important and funda- mental in all shop administration, the lilting and moving of masses. The first four chapters are devoted to a discussion of the levers BOOK REVIEWS. 159 and jacks, tackle and blocks, windlasses, winches and lifts, elevators, hydraulic and pneumatic. The types selected for the illustrations and discussions are characteristic and admirable, and the illustrations, like so much of the German work of this class, are most enjoyably clear and satisfactory. The method of treatment is to evaluate in every case the theoretical effort and the hurtful resistance to be expected in every combination and from these two to work out the efficiency. The chapter on elevators with its discussion of an accumulator and its relation to hydraulic transmissions is most interesting and satis- factory, and, so far as is known, is the only one which has appeared. The fifth chapters covers hoisting machinery for mines with their detail of brake and compensating devices and safety attachments for cages. The chapter on cranes and sheers is particularly satisfactory as bring- ing together material which has not heretofore been accessible in any one place. The travelling crane does not receive the discussion which its importance in this country would demand, but the author very prop- erly refers to the difficulty of finding formulae which would be generally applicable. The final chapters on dredges, excavators and pile-drivers are specially interesting as presenting forms of apparatus with which American en- gineers are not so familiar, and which can at once be applied to other standard forms. For students and others seeking general conceptions concerning ap- paratus of this sort, and for those seeking a superficial familiarity with their construction and operation, the book will serve a most admiral)le purpose and will be a valuable addition to the student's library. The difficulty with it is that he who seeks to obtain definite and exhaustive study of the forms which he would be likely to meet will be disappointed in that the things which he wanted most to be told are the very things concerning which the theoretical discussion is silent. This is, however, so frequent a limitation of the text-books written by those comy)eten| to prepare them from a theoretical standpoint that it is perhaps unfair to feel disappointment for that which could not have been helped in the nature of the case. F. R. H. Helical Gears: A Practical Treatise by a Foreman Patternmaker. Mac- millan & Co, 1894. i2mo. 127pp.$2.00.
The author of this treatise in the '* Specialist Series ** has made him-
self known to readers in contributions to the technical journals, but
veils his identity under the simple initials J. H.
By the term *' Helical Gears" he means those in which the elements
of the teeth which in plain spur gears are parallel to the axis have been
inclined so as to becoitie either elements of the hyperboloid or ])arallel
to the elements of a helix. It is a principle familiar to students of trans-
missive machinery that in tooth gear the friction of two teeth upon each
other increases in any pitch as the attempt is made to increase the arc
of contact of any two teeth. Where heavy powers are to be transmitted
from one tooth to another, the necessity is laid upon the designer to
make the teeth strong by supplying them with the necessary metal, and
this compels a large circular pitch. With the large circular pitch the
difficulty from insufficient contact and from friction of conta( t increase
as the numbers of teeth are diminished on a given length of the cir-
i6o THE QUARTERLY.
cumference. It is further a difficulty with massive teeth that by reason
of their corisiderable projection beyond the pitch line the obliquity of
action becomes troublesome and excessive.
So far as known the first solution to mitigate these difficulties was pre-
sented by Dr. Hooke as far back as 1674, who proposed that the face of
the wheel should be made up of a series of gears, the teeth of each being
set a little in advance of that of its neighhor, so that in looking across
the wheel the teeth appeared in steps. It will be seen by this suggestion
the strength o^ a massive pitch was retained, but the smoothness of
working and diminished obliquity of a great number of small teeth were
secured at the same time. The difficulty of forming these step teeth
and of machining them have practically thrown them out of use, but
the principle is retained in those forms of teeth in which the series of
steps becomes infinite in number and the broken lines become elements
of helices.
It is almost universal in order to eliminate the thrust lengthwise of
the axis which follows from the use of a series of helices, right-handed
or left-handed, on either wheel, to use on each wheel two segments of
right- and left-handed wheels which meet in a point at the centre of the
.face ; this gives the form of tooth which resembles a V, and is sometimes
known as V- teeth or ** herring-bone *' back. These V-teeth in older
designs and less carefully made, often have the elements perfectly straight,
but a moment's thought will show that this is a mongrel form and cannot
be expected to secure either the smoothness or the reduced friction
which will result when true mathematical surfaces are used.
The first pages of the treatise are very properly devoted to the discus-
sion of the fundamental peculiarities of the laying out of teeth, both
upon a cylinder and upon a cone, the development upon a conical sur-
face being a feature of design which has not received very much atten-
tion and development in this country ouiside of a few specialists. The
remainder of the book is mainly taken with the actual construction of
the blocks which are to be used in a special gear moulding machine,
intended to be used for the shaping of teeth without the use of a
helical work as compared with the method of working from a pattern,
since the withdrawal of the teeth block from the sand can be done with
the machiue in a radial direction, whereas the withdrawal of a full pat-
tern is a very difficult and vexatious operation, and is very likely to seri-
ously injure the moulded forms of the teeth. A chapter, however, is given
to the construction of patterns where for any reason their use seems to be
compelled. The moulding process, with the machine and with the pat-
tern, and instructions for the design of tooth profiles, either by the exact
or the approximate method, completes the practical part of the book.
It is directed more towards the foreman patternmaker than to the en-
gineer, but the latter will find in it much matter which, so far as known
to the reviewer, has never been presented in as satisfactory form in any
other treatise. The criticism is j>erhaps to be made that the treatise as-
sumes a certain amount of knowledge on the part of the reader, of gear
moulding machines and of the significance of the special conditions laid
down for the design of gears, but, of course, this is to be explained by
the fact that the treatise announces itself as for specialists, to whom such
information is well known or at hand. Students, of course, will find this
limitation an obstacle in their path. F. R. H.
BOOK REVIEWS. 161
A Manual OF Practical Assaying. By H. Van F. Furman, E.M. John Wiley &
Sons, New York. 1893. ^^'O* 39^ pp. $3.00. « The book is divided into four parts. Part I. discusses sampling ores and metallurgical products, giving in detail the latest methods of hand and mechanical sampling, preliminary examination both by the blow- pipe and by wet methods ; operations and apparatus, including furnaces ; reagents giving the fluxes, reducing agents, etc., used in fire assays; also the ordinary reagents used in the quantitative analysis. The chapters on sampling and preliminary testing are excellent. Part II. gives the rapid methods for the determination of silica, sul- phur, phosphorus, carbon, carbonic acid, water, gold and silver, mercury, lead, arsenic, antimony, tin, copper, bismuth, cadmium, iron, aluminium, chromium, titanium, manganese, zinc, nickel and cobalt, calcium, mag- nesium, barium, sodium and potassium. This division of the work con- sists of more than one hundred and fifty pages, and gives most of the methods usually described in books on quantitative analysis. The space given to fire assays of lead, antimony and tin is, however, very limited. Part III. is devoted to special commercial analyse? and assays, includ- ing base, gold and silver bullion, coal, water, white lead, phosphates and slags. This is the best portion of the work and contains many practical tests not often described in books, such as the chlorinaiion assay of gold ores. Part IV. consists of examples of chemical and metallurgical calcula- tions and tables of weights, specific gravity, etc. Their author considers an assay as any rapid method of determination, therefore his book is more nearly comparable to Beringer's assaying than to works treating only of fire assays. The methods given are in accord with the latest improvements, and are succinctly and clearly stated, giving sufficient detail for their practical manipulation. The book is well arranged and will prove a most useful manual for both assayers and chemists. E. H. M. Retort of the Geological Survey of Ohio Vol. VII., Pt. I , p. 1-290. The appearance of this report which is devoted largely to the clays and clay working industries of Ohio, will be a source of much gratifica- tion to many. After an explanation of the geological structure of Ohio, there fol- lows a description of the clays and shales of the State by Prof. Orton, in which the extent, thickness and qualities of these formations are set forth. Prof. Orton states that the clays of Ohio are of much greater value than her coals. The chapter on the clay-working industries of Ohio, by Mr. Edward Orton Jr., deserves much praise. It is only within the last few years that the various states have recognized the value of their clay resources, and in consequence are making them the subject of special investigations. New Jersey was the pioneer in such work, and her clay report of 1878 is of permanent value. Ohio followed her example, and the report of 1884 contained an exhaustive article on her clay industries by Mr. Orton. These industries have not only grown greatly in the last ten i62 THE QUARTERLY. years, but new branches have sprung up, so that another report was deemed necessary. After a discussion of the properties of clay Mr. Orton takes up the manufiicture of pottery, paving material, pipe and hollow goods, refractory materials and building material^. Under each heading are discussed the various methods employed, their advantages and disadvantages, and the forms of machinery used. Numerous analy- ses add to the value of these discussions. A number of measurements were made of the temperatures in kilns during the different stages of burning ; the readings were taken with a lunette pyrometer. Numerous tests were made of bricks from many factories, not alone to determine their individual merits, but to test the relative strength and wearing qualities of bricks made by different methods. The methods of mining the chy are not discussed, and it is to be regretted that there is not more information concerning the cost of pro- duction. The whole report is written in a clear, concise way, and shows not only the result of much labor, but also a thorough knowledge of the subject. It will serve as a standard work on those branches of the clay working industry of which it treats. The fourth and last chapter of the report, on the coal-fields of Ohio, is by Prof. Orton. The extent, thickness and horizon of the various seams are carefully discussed. H. R. A Field- Book for Civil Engineers, By Daniel Carhart. C. E. Ginn & Co, Boston. The author uses the above general title probably because he makes reference to surveys for highways, but the book is principally intended for railway engineers. Its chief value, however, lies in the service it can be to instructors. Ordinarily the teacher of railway surveying will find that one book will be best for the practical details of running a survey, another will have the best tables, still another will treat curves in a superior manner, while most of them are loaded down with a mass of crude mathematics of use to no one. Professor Carhart has given the best average work on the market for purposes of instruction, and this fact does not invalidate it for practice also. There are criticisms to be made, as for example, a rather useless series of formulae for slope stake work, which is after all, head work ; also the book fails — as indeed do nearly all — to place before the student the problem that feces him when he is in the field with a certain alti- tude to reach and a wide range of country to select his grade upon. But possibly no one can thoroughly appreciate such problems until he meets them face to face in the field and it may be the part of wisdom to leave them to field discussion, and not to attempt them in the class room. The tables at the end are a good selection from the various ones scattered through other books. J. L. G. INDEX JO MINERALOGICAL LITERATURE. 163 INDEX TO MINERALOGICAL LITERATURE. By a. J. MOSES and L. McI. LUQUER, Principal Abbreviations Used. Amer. Jour. Sci, — The American Journal of Science (New Haven). BulL Soc, Min. — Bulletin de la Societe Fran<;raise de Mineralogie (Paris). Min. Ma^. — The Mineralogical Magazine (London). Minn. Mitth. — Tscherraak's Mineralogische und Petrographische Mit- theilungen. Neues Jahrb. Min. — Neues Jahrbuch fiir Mineralogie, Geologic und Palaeontologie (Stuttgart). Zeit.f. Kryst. — Zeitschrift fiir Krystallographie und Mineralogie (Leip- zig)- Gior. di Min. — Giornale di Mineralogie, Cristallografia e Petrografia (Milan). CompL Rend. — Comptes Rendus des Seances de 1 Acad^mie des Sciences. I.— Mineral Species. Aguilarite, Etc. Contributions to Mineralogy, No. 54, F. A. Genth. With rrys- tallographic notes; by S. L. Penfield, in Amer. Jour. Sci., 3d, xlivr., 381-388, November, 1892. Analyses of aguilarite, metacinnabarite, lollingite, quartz, fluo- rite, zircon, lepidolite, fiichsite, rutile and danalite, with crystal notes on last two. Alabandite, Etc. Alabandite from Tombstone and Wavellite from Florida. — A. J. Moses and L. McI. Luqiier, School of Mines Quarterly, xiii., 236-239, April, 1892. Albite, Etc. Albit, Analcim, Natrolith, Prehnit und Kalkspath, Vervvitterungs- producte eines Diabases von Friedensdorf bei Marburg. — R. Braun in I^eues Jahrb. Min.^ r892, II., 1-24. Ai.lanite. Fund von Allanit (Cerin) bei Gyttorp, Bergdist, Nora, Schweden. — G. Nordenstrom, in Geoi. Foren. Fork., 1890, vol. xii., 540 ; abs. in Zeit.f. Kryst.^ vol. xx., p. 386, 1892. Amphibole. Ueber die Chemische Constitution der Hornblende ; H. Haefrke, Inaug. Disert., Gottingen. — Abs. Neues Jahrb. Min.^ 1892, II., 404- 406, Ref. Analcite. Suir Analcime del Monte Somma. — P. Franco in Gior. di Min., iii., 232-237, 1892; Optical Study, with colored plate. i64 THE QUARTERLY. I Aiialcite as Rock Constituent. — W. Lindgren in Proc, Calif, Acad. Soc.j 1890 (2), vol. iii., 39 ; abs. in Zeit, /. Kryst., vol. xx., p. 498, 1892. Andalusite. Ueber Chiastolith. — F. Becke in Min. Mitth.^ xiii., 256-257, 1895. Anglesite, Etc. Anglesite associated with Boleite. — F. A.Genth in Atner./our, Sct\y 3d, xlv., 32, January, 1893. Anhydrite. Kiinstlich hergestelle Krystalle von Anhydrit. — K. Haushofer, in SiiZ'Ber. d, MatJu-Phys, Akad. d, Wiss., 1889, vol. xix., 12 ; abi. in Zeit,f. KrysL, vol. xx., p. 304 1892. Anorthite. Ueber eine Merkwiirdige Eigenschaft des Anorthit. — E. v. Fede- row, Neuesjahrb. Min.^ ^892, ii., 68-69. That the optic axis which makes an angle of 6^° with the vertical axis is an optic twining axis. — Also in Minn, Mitth.^yXx.^ 443, 1892, and Zeitf, KrysL^ xx., 362, 1892. Apatite, Etc. Minerals from the Apatite-bearing veins at Noerestad, Norway. — R. H. Solly, in Mineralogical Magazine^ x., 1-7, July, 1892. Apatite, rutile, zircon, wernerile, amphibole, pyroxene, titaniie crystals de- scribed. Influence of Swamp Waters in the Formation of Phosphate Nodules of S. C. — C. L. Reese, in Amer, /our, Sci,, 3d, xliii., 402- 406, May, 189^2. Aphthitalite. Suir Aftalosa del Vesuvio. — Pasquale Franco, in Gior, di Min,^ iv., 151-156. The accepted hexagonal form was observed on artificial crystals not on natural. Thin tabular crystals herein described are biaxial, orthorhombic, and in angles closely agree with the arcanite of Haid- inger. Apophvllite. Mineralogische Mittheilungen, xiii. — C. Klein, in Neues Jahrb, Min,, 1892, ii., 165-231. The system of apophyllite and the influence of heat and pressure on its optical properties. Arsenopvrite, Etc. Beitrage zur Mineralogie Bohmens. — Friederich Katzer, in Min, Mitth,^ xii., 416-428, 1892. Arsenopyrite, sphalerite, siderite, wollastonite, andalusite, tour- maline, iolite, gypsum, etc. Aurichalcite. Aurichalcite and decomposed Chalcopyrite from Torreon, Chi- huahua, Mexico. — H. F. Collins, \xs. Mi neralogical Magazine^ x., 15- 19, July, 1892. INDEX TO MINERALOGICAL LITERATURE. 165 AWARUITE. Awaruite. — G. J. Ulrich, in Quart, Journ, GeoL Soc, 1890. vol. 46, 619; abs. in Zeit, /. Krjsi, vol. xx., p. 517, 1892. AXINITE. Axinit im Harze und die chem. zusammensetzung des Axinits iibcrhaupt. — O. Luedecke, in Zei/schr^ f, Aaturtuiss^ HalU^ 1889, vol. 62 ; abs. in Zeit. f. Kryst.^ vol. xx., p. 310, 1892. Bastite. Bast it aus der Fruska-Gora. — M. Kispaiic in Jahrb, d, k, Ungar. GeoL AnsL^ 1889, vol. viii., p. 197; abs. in Zeit, /. Ktyst., vol. XX., p. 301, 1892. Beryl. Etched Beryls from Mount Antero, Colorado. — R. C. Hills in I^roc, Col. Scient, Soc,^ iii. pt. ii., 1889, p. 191-192. Beyrichite. Beyrichit von der Grube Lammerichskaule bei Altenkirchen im Siegen*schen. — H. Laspeyres, Zeit, f, Kryst,^ xx., 535-550, 1892. Boracite. Ueber die Abhiingigkeit der Specifischen Warme des Boracits von der Temperatur. — K. Y^xotVitx^ Neues Jahrb. AJin,^ 1892, II., p. 91-107. Braunite. Braunit von Langbanshyttan. — G. Flink, in Bihang t. Sv. Vet- Akad. Hand,, 1890, vol. xvi., II., 4, 1-23. — Abs, in Zeit, f, Kryst,^ vol. XX., p. 368, 1892. • Brazilite, Etc. I — Ueber Brazilit, ein neues Tantal-Minerde von der Eisenraine Jacupiranga, Sud Sao Paulo. II. — Ueber brasilianische Leucitges- teine, 111. — Nochmals die Leucit " Pseudokrystall " Frage. — E. Hussak in Neues Jahrb. Min.^ 1892, II„ 141-160. Brookite. Ueber Brookit als Contactmineral. — R. Beck in Neues Jahrb, Min,, 1892, I., 159. Ueber den Brookit von Beura. — G. Streuver, Rivista di Min, e, Crist, ^ 1890, 6, 56; abs. Zeit, f, Kryst,^ xx., 624, 1892. Calcite. Relation entre la vitesse d*attaque du spath par les acides et r^lasticit^ optique estim^e suivant la direction normale au plan d'aitaque. — G. Cesaro, Ann, d Chim, et de Phys. 6, xvii, 37-52, 1889. Sur la vitesse d'attaque du Marbe et der Spath d'Islande par quelque acides. — An, de la Soc, GeoL de Belgique, xv., 219, 1887- %2>\ abs. Neues Jahrb. Min,^ Ref. 1892, I., 221-222. Sur la vitesse de Reaction du Sp^th d'Islande avec quelques acides. — W, Spring, Bull, de V Acad Roy, de Be/gigue^i,, xiv., p. 13, and 725-736. i66 THE QUARTERLY. Sur la Vitesse de dissolution du Spath d*Islande dans I'acide chlorhydrique. — W. Spring, Bull, de la Soc, Chim, de Paris ^ 3d, III., 177-184, 1890; abs. in Neues Jahrb, Min.^ Ref. 1892, 221. Gleitflachen am Doppelspath. — A. Kenngott in Neues Jahrh, MiN.j 1892, I., 219-221. Krystallfornnen des Calcite von Rhisnes. — G. Cesaro, in Ann. Soc. GeoL d. Belg,y 1889, vol. xvi., 165 ; abs. in Zeit. f. Kryst.^ vol. XX., p. 283. Bemerkungen iiber die Islandischen Fundstellen von Doppet* spath. — Th. Thoroddsen, in GeoL Foren, Foih^ 1890, 247-254; abs. in Zeit. f. KnsL, vol. xx., p. 376. Idiocyclophane calcite crystals. — H. G. Madan, in Nature^ 1890, vol. 42, 99. — Abs. in Zeii. /. Krysl., vol. xx., p, 517. 1892. Mineralogische Beobachtungen. — H. Hofer in Min, Mitlh,^ xii., 487-504, 1892. Corrosion of calcite crystals of Steirdorf, and Rawies. I'he bexoctahedron on fluorite of Sam thai Tyrol due to corrosion. Celestite, Etc. Sur quelques mineraux provenant de Condorcet (Drome). — L. Michel, in BulL Soc, Aiin,^ xv., 27, February-March, 1892. Cryslallographic description of quartz, calcite and celestite. Chalcopyrite. Haarformiger und gestrickter kupferkies von der Grube Hein- richssegen bei Musen. — H. Laspeyres, Zeit. f, Kryst^ xx., 529-534, 1892. Chlorites. Die Chloritgruppe.— G. Tschermak, 5//2. Wien Akad., i Theil., 99, I., 1890, pp., 1-94. II. Theil., 100, 1891, p. 79. — Abs. Neues Jahrb. Min.^ 1892, II., 218-232, Ref. Chromite Analysis of Chromite.— E. Waller and H. T. Vult6, School of Mines Quarterly, xiii., 225-230, April, 1892. Cinnabar. Quecksilberlagerstatte von Almaden in Spanien. — H. Pohlig, in Sitz.'Ber. niederrhein. Gts. fur Natur-u. Heilk.^ Bonn, 1890, 115- 116; abs. in Zeit.f. Kryst.^ vol. xx., p. 526. Cliftonite. Cliftonit aus dem Meteoreisen von Magura. — A. Brezina, in Anal. k. k. Nat. Hist., Hofmus, 1889, vol. iv., p. 202 ; abs. in Zeit. f. Kryst.y vol. xx., p. 292, 1892. Cobaltite. Zwillinge von Kobaltglanz nach die Oktae Jerflache von der Grube Wingertshardt bei Siegen. — H. Laspeyres, in Zeit. f. Kryst.^ vol. XX., p. 550, 1892. Cohenite, Etc. Einige Bestandtheile des Meteoreisens von Magura. Arva. Ungarn. — E. Weinschenk, in Zeit.f. Kryst.^ vol. xx., No. 3, p. 291, 1892. Cohenite, a new mineral, mentioned. INDEX TO MINERALOGICAL LITERATURE. 167 COOKEITE. Cookeite from Paris and Hebron, Maine. — S. L. Pen field, in Amer. Jour, Set'., xlv., 393-396, May, 1893. Corundum. Occurrence of Sapphire in Scotland. — M. F. Heddlc in Miner- alo^icai Magazine y ix., 389-390, December, 1891. A single crystal in andalusite of Clova, Aberdeenshire. Blauen und gemeinen Korund aus den> Siebengebirge. — H. Pohlig, in Verh Naiuthist. ver. der RhtinL^ etc., Bonn, 1888,92-94; abs. in Zeit,f. Kryst.y vol. xx., p. 524, 1892. Crocoite, Etc. Synthesis of the minerals Crocoite and Phcenicochrojte. — C. Ludeking in Amer.Jour. Sei., ^d, xliv., 57-58, July, 1892. By exposure to air of a solution of lead chromate in caustic potash. Danalite. Danalite from Cornwall. — H. A. Miers and G. T. Prior in Mineralogical Magazine, x., 10-14, July* 1892. Datolite, Datolite from Loughboro, Ontario. — L. V. Pirsson, in Amer, Jour. 5a., 3d, xlv., 100, February, 1893. Description of large, magnificent crystals. Diamond. Sur Texislence du diamant dans le fer m^t^orique de Canon Diablo. — M. C. Friedel, in Buii. Soe. Min., xv., 258-263, Novem- ber, 1892. Proves the diamonds by burning them. Dioptase, Etc. Sur I'argent natif et la dioptase du Congo Frangaise. — E. Jan- net taz, Compt. Rend., cxii., 446-447, 1891. Dioptase from Comba mine, with quartz and chrysocolla. Epidote. The Epidote of Ala. — G. La Valle, yii/i, d. R. Acead. d. Lincei, 1890; abs. in Zeit.f. Kryst., xx., 621, 1892. Epsomite. Epsomit krystalle von Stassfurt-Leopoldshall. — L. Milch, in Zeit. f. Kryst., vol. xx., p. 221. Ettringite, Etc. Mineralogical Notes. — A. J. Moses, Amer, Jour. Sei., xlv , 488- 493, June, 1893. Pyrite crystals from King's Bridge ; ettringite from Tombstone, Arizona. Euclase, Etc. Mineralogische Notizen ausBrasilien. — E. Hussak, in Min. Mi/f., xii., 457-475» 1892. Brookite, cassiterite, xenotime, monazite, and a new locality (Bahia) for euclase. i68 THE QUARTERLY. FiCHTELITE. Ueber den Fichtelite. — Abstract articles by Hell, Bamberger and Spiegel, in Neues Jahrb, Min,^ 1892, ii., 241 ; ref. Probably Fluorite. On the use of fluorspar in optical instruments. — Sylvanus P. Thompson, in PhiL Mag,^ 31, 120-123, 1891. FOUQUEITE. Fouqu^ite. — Al. Lacroix, abstract Zeif.f, Kryst.y vol. xx., p. 290, 1892. Friedelite. Friedelit von Harstigen. — G. Flink, in Bihang t. Sv, Vet^-Akad. handl., 1890, vol. xvi., ii., 1--23 ; abs. in Zftt f, Kryst.^ vol. xx., p. 371, 1892. Gadolinite. Zusammensetzung des Gadolinit. — C. W. Blonistrand, Lunds Univ, Afskri/t, 1888, vol. 24; abs. in Zeit f. Kryst, yo\. xx., p. 366, 1892. Studien iiber Gadolinit. — W. Peterson, in GeoL Foren, Forh.y 1890, 275-347 ; Abs. in Zeii, f. Kryst.^ vol. xx., p. 376, 1892. Gahnite. Kreittonit von Bodenmais. — K. Oebbeke, in Sitz.-Ber. de Phys, Med, Soc^y 1889, vol. xx., p. 41 ; abs. in Zeit. /. Kryst.y vol. xx., p. 310, 1892. Galenite, etc. Neue Form des Galenit. — G. Cesaro, in Zeit, f, Krysf,, vol. xx., p. 468, 1892. La Mineralogie du Plateau Central. — F. Gonnard, in Buii. Soc. Min,^ XV., 28-35, February-March, 1892. Notes on zeolites, forms of galenite of Pontgibaud and corrosion figures Beryl of Droiturier, psilomelane and ps^udomorphic quartz. Garnet, Etc. Canadian Spessartite and Mountain Cork.— B. J. Harrington in Canadian Record of Science, Oc\ohQT, 1890, p. 225-228. Striated Garnet from Buckfield Me., parallel to intersection of 211: no. — W. S. Bayley, Amer, Jour, Sci., 3d, xliv., 79, July, 1892. La Pyr6n6ite. — Ch. Frossard, in Bu//. Soc. Min,^ xv., p. 58-61, February-March, 1892. Note sur les Calcaires noirs a pyr^n^ite. — Ed. Jannettaz, in BulL Soc, Min.,-yiw,^ 62, February-March, 1892. Eine Bemerkung zur Abhandlung von E. Mallard Sur le grenat Pyr^n^ite, R. Brauns, \xi Neues, Jahrb. Min,^ 1892, L 217-219. Disputes Mallard's theory that Pyr^n^ite is orthorhombic in symmetry but grouped in form of rhombic dodecahedron. Garnierite. Nickel ore from New-Caledonia. — T. Moore, in Chem. News,, 1890, vol. 62, 180; abs. in Zeit. f, Kryst., vol. xx., p. 518, 1892. INDEX TO MINERALOGICAL LITERATURE. 169 Garnierit (NIckeJgymnit) von Foldalen, Norwegen.~Chr. A.* Miinster, in Archiv. for Matemat. und Naturvidenskab^ vol. xvi., 240: abs. in ZeiL f. Kryst,^ vol. xx., p. 402, 1892. Gav-Lussite. Gay-Lussite from San Bernardino Co., California, — H.G. Hanks, in Mining and Scientific Press y March 26, 1892, GlSMONDITE. Gismondin vom Hohenberg bei Buhne in Westfalen. — F. Rinne, in Sitzingsber. Preuss. Akad. d, fViss., Berlin, 1880, 1027 ; abs. in Zeif. f. Kryst.^ vol. xx,, p. 302, and N^eues Jahrb. Afin»y 1892, 1., 505 Ref. Graphite. Graphite from Borrowdale, Cumberland. — J Postlethwaite, in Quarts Jour n. GeoL Soc, 1890, vol. xlvi., 124; abs. in Z«/. /. A'ryst.f vol. xx., p. 517, 1892, Graphitgange im zersetzten Gneiss von Ceylon. — J. Walther, Zeitschr, d, deutsch, GeoLy 1889, vol. xli., p. 359 ; abs. in Zeit, f. Kryst.y vol. xx. p. 290, 1892. Gyrolite. Optic Properties of Gyrolite. — M. F. Heddle, in Mineralogical Magazine ix., 391, December, 1891, Halite. Das Tetrakishexaeder (102) am Sleinsalz von Starunia. — A. Pelikan in Min, Mitth,^ xii., 483-486, 1892. Halloysite. Lenzinit. — K. Haushofer, in Sitz. Ber. d. Math.-Phys, CL Akad: d. IViss.f 1889, vol. xix., 13 ; abs. in Zeif. /, K^yst., vol. xx., p. 304, 1892. Hausmannite. Hausmannit von Jakobsberg. — G. Flink, in Bihang /. Szk Vet.- Akad, HandL 1890, vol. xvi., II, No. 4, S. 1-23; abs. in Zeit f, Kryst,^ vol. xx., p. 369, 1892. Hauynite. Doppeltbrechenden Haiiyn. — W. Bruhns, in Sitz, Ber, niederr- hein Ges, fur Naiur. u, Hetlk,^ Bonn, 1890, 30-31; abs. in Zeit. f, Kry^t,, vol. XX., p. 526, 1892. Helvite. Helvin von Kapnikbanya. — A. Kalecsinozky, in Zeif. f Kryst., vol XX., p. 365, 1892. Chemical analysis given. Hematite. Clinton Iron Ore. — C. H. Smyth, Jr., in Amr, Jour. Sci,, 3d, xliii., 487-496, June, 1892. A discussion of structure and forma- tion. Occurrence of Hematite and Marti te Iron Ores in Mexico. Robert T. Hill, in Amer. Jour, Sci,, 3d, xlv., 111-119, February, 1893. Economic description. VOL. XV. — 12 I70 THE QUARTERLY. Herderite. Herderite from Hebron, Maine. — H. L. Wells and S. L. Pen- field, in Amer.Jour. Set'., 3d, xliv, 14, August, 1892. Complete description. Heulandite, Etc. Ueber die Beziehung zwischen den Mineralien der Heulandit- und Desmin gruppe. — F, Rinne, in Neues Jahfb, Min.y 1892, I., 1 2-44. lOLITE. Cordierite as contact mineral. Yasushi Kakuchi. — 'Journal of the College of Science \ Imperial University Japan, III., 313-334 ; abs. in Zdt. f Kryst,^ vol. xx., p. 501, 1892. Jacobsite, Etc. Mineralogische Mittheilungen. L. J. Igelstrom, in GeoL Foren, Fork., 1890, 137-139 und 440-443; abs. in ZeiL f Kryst,y vol. xx., p. 375. 1892. Jacobsite braunite, neotesite, chlorarsenate of lead, hausmanite. JOSEPHINITE. Josephinite, a neAv Nickel-Iron from gravel in stream in Oregon. W. H. Melville, in Amer. Jour, 5r/., 3d, xliii, 509-515, June, 1892. Kentrolite. Kentrolith von Langbanshyttan. — G. Flink, in Bihang /. Sv. Vet,- Akad. Handle 1890, vol. xvi., II., No. 4, S. 1-23 ; abs. in Zeit. f Kryst^ vol. xx., p. 370, 1892. Kermesite. Rothspiessglanzerz. — P. Pjatnitsky, in Zeit. f Kryst., vol. xx., p. 417, 1892. Leadhillite, Etc. Minerals from Leadhills. — N. Collie, in Journ. Chem. Soc. Lon- don, 1889, ^o^' *^-i P- 9^ > ^t>s. in Zeit. f Kryst., vol. xx., No. 3, p. 284, 1892. Minerals mentioned : Leadhillite, lanarkite, chalcedony, linarite, pyromorphite, vanadinite, plumbocalcite, aragonite, strontianite, dolomite, calamine and lime-vanadium pyromorphite. Magnetite. On the presence of Magnetite in certain Minerals and rocks. — Liversidge, in Tram. Austral. Assoc. Adv. Science, 1891 ; abs. in Amer. Jour. Sci., 3d, xlv , 76, January 1893. Showing that magnetism of chromite, spinel, franklinite, etc., is due to scattered panicles of magnetite. Manganophyllite. Manganophyll von Langban. G.YVmV, Bihangtill Kgl.Svenska. Vet. Akad. Bd., xiii., II, p. 70; abs. in Neues Jahrb. Min., 1892, II., 232, Ref. Mineralogische Studien. — A. Hamberg, in Geol. Foren. Fork., 1890, vol. xii., 567-632; abs. in Zeit. f Kryst., vol. xx., p. 387; and in Neues Jahrb. Min., 1892, II., 233-237, Ref. INDEX TO MINERALOGICAL LITERATURE. Xyi Manganophyllite, chlorite containing manganese, ganophyllite, pyrophanite, ilmenite-hematite group, rhodonite and crystallo- graphic discussion Meionite. Die Formel des Vesuvischen Meionite. — A. Kenngott, in Neues Jahrb, Min,, 1892, I., 48-53. Mrlanophlogite. Sur une nouvelle publication relative a la melanophlogite. — George Friedel, in Buii. Soc. Min,^ xv., 49-58, February-March, 1892. Melilite. Enstehung von Melilith beim Brennen von Portland Cement. — G. Bodlander, in N-eues Jahrb, Min.., '892, I., 53. Little tetragonal crystals found light-brown in calor^ melilite in composition and angles. Menaccanite, Etc. Bemerkungen «ber einige Mineralien ausdem Fichtelgebirge, — F. V. Sandberger, in Ntuesjahrb, Afim.^ 1892, II., 25-37. Menaccanite, rhodochrosite, margarodite, chlorite, lepidolite, etc. Micas. Experiments upon the Constitution of certain Micas and Chlo- rites. — F. W. Clarke and.E. A, Schneider, in Amer. /oun Sci., 3d, xliii., 378-386, May, 1892- Continuation of work on the constitution of the natural silicates. Milarite. Ueber die Zusammenseteung des Miiarites. — F. P. Treadwell, Neues Jahrh. Min.^ 1892,!., 167. R,0,2CaO,AljO,i2SiO,. Molybdenite. Darstellung des Molybdanit. — A, von Schulten, in Zeitf^ Krysi,^ vol. XX., p. 283, 1892. Mqnazite. Notice cristallographique sur la monazite de Nil St Vincent. — BulL Acad, Belg.^ 3 S-, xxi., 40-48, 1891 ; abs. Neues Jakrb, Min,^ 1892, II., 403, Ref. Monazit von UraL — C. W. Blomstrand, in Lunds Univ. Arskrift,^ 1888, voL XXV., Abth. 4^ Abs. in Zeit /. Kryst,^ vol. xx., p. 367, 1892. Natrolite. Analysis and crystal lographic study of some Venetian Natrolites. — Rivista di Min. E Crist, ItaL, 1890, 7, 16 and 69; abs. in Zeit, f. KrysL^ XX,, 628, 1892, Nickel-Brejthauptite, Etc. Mineralogical Notes. — School of Mines Quarterly, xiv., pp, 49-56, November, 1892. A probably new Nickel Arsenide, E. Waller and A. J. Moses. 172 THE QUARTERLY. Graphite and Magnetite Pseudomorphs, A. J. Moses. Orthoclase, from Canada^ B. C. Hinnan. Topaz, from Japan, W. D. Matthew. NOCERITE-LIKE MINERAL. Ein Nocerin-ahnliches Mineral von Arendal in Norwegen. — F. v. Sandberger, in Neues Jahrb. Min,, '^92, I-, 221. OCTAHEDRITE. Anatas von Bourg d'Oisans, Dauphin^. — K. Biisz, Zeit, f, Kryst,^ XX., 557' '892. Okfretite. Sur roffrttite espfee mineral noavelle. — Compt, Rend,, cxi., 1002- 1003, 1890. Orthoclase. Vicinalflachen an Adularzwillfngen nach dem Baveno-Gesetze. — von Zepharovich, in Siiz-Ber. d. k. k. Akad, d. Wiss., Wien, 1889, vol. xcviii. (i), p. 404; Abs. in Zeii, /. Krysi.y vol. xx., p. 301, 1892. Pentlandite, Etc. Pentlandite from Sudbury, Ontario, Canada, and remarks upon three supposed new species from the same region, S. L. Penfield, in Amer/jour. Set., xlv., 493-497, June, 1893. Blueite, whartonite and folgerite are not distinct species. PiNlTE. The Pinite of Breagein Cornwall. — ^J. H, Collins, in Mineraiogi- cai Magazine , x., 8-9, July, 1892. Pholidolite, Etc. Mineralien aus Drusenraumen von Taberg in Wermland. — G. Nor- denskiold, in GeoL Foren. ^i?M., 1890., vol. xii., 348-358; abs. in Zeit.f. Krysf.^ vol. xx., p. 382, 189?. Pholidolite, garnet, diopside, epidote, apatite. Platinum. The Supposed Occurrence of Platinum in North Carolfna. — F. P. Venable, in Journ^ Elisha Mitchell Sci. Soc,^ viii,, Pt. IL Concludes that evidence of occurrence has very slight value. Plattnerite. Plattnerite, occurrence near Mullan^ Idaho^ and crystallographic notes. — W. S. Yeates and E. F. Ayres, in Amer. Jour, Sci., 3d, xliii., 407-412, May, 1892. Polybasite. Polybasite and Tennanite from the MoUie Gibson Mine in Aspen, Colo. — S. L. Penfield and S. H. Pearce, in Amer. Jour, Sci,, 3d, xliv., 15-19, July, 1S92. Both minerals occur massive, the polybasite also in tabular crystals in siderite. INDEX 10 MINERALOGICAL LITERATURE. 173 Predazzite, Etc. Ueber Predazzit und Pencatit. — Ottpkar Lenecek, in Min. MUth,^ xii., 429-442 and 447-456, 1892. That these stones are not mixtures of calcite with brucite, but contain chiefly octahedral kernels composed of very fine, densely packed fibres or needles of hydromagnesite (pseudomorphed after periclase, etc.). Prehnite. Prehnit aus dera Floitenthale. — H. von Foullon, in Veri. k. k. geol Reichsanst^ 1889, p. 197 ; abs. in Zeit. /. KrysL, vol. xx., p. 294, 1892. PSEUDOBROOKITE, , Pseudobrookit von Aranyerberg in Siebenbergen. — H. Traube, in Zeit.f. Kryst.y vol. xxi., p. 327, 1892. Ueber eine Zufallige Bildung von Pseudobrookit, Hamatit und Anhydrit als Sublimations Producte, Bruno Doss, in Zeit.f. KrysL, XX., 566-587, 1892, with Literature of pseudobrookite. Ptilolite, New Occurrence Ptilolite. — Whitman Cross and L. G Eakins, in Amer, Jour, Set',, 3d, xliv,, 97-100, August, 1892. General discussion of the mineral. • Constitution of Ptilolite and Mordenite. — F. W. Clarke, in Anier, Jour. ScL, 3d, xliv., 10 1, August, 1892, Discussion of formulae. Pyrargvrite. Pyrargyrit von Mexico. — K. Busz, in ZfiL /. Kryst, xx., 557, 1892. PVRITE. Kobaltund Nickelreicher Eisenkies von der Grube Heinrichs- segen bei Miisen. — H. Laspeyres, in Zeit.f, Krysi., xx., 553-555, 1892. Pyroxene. Beitrage zur Kenntniss der Pyroxenfamilie in chemischer und optischer Hinsicht. — E. A, Wiilfing, Habilitationsschrift der Uni- versiidt Tubingen^ 1891, 65 pp.; abs. in Neues Jakrb. Min.^ 1892, II.. 23 ref. Pyroxene Analyses. — T. M, Chatard, Am, GeoL^ 1890, vol. vi., 35 ; abs. in Zeit/f. Kryst., vol, xx., p. 501, 1892. Fibrous Intergrowth of Augite and Plagioclase in a Minnesota Gabbro. — W. S. Bayley, in Amer, Jour. Sci\, 3d, xliii,, 515-520, June, 1892. Ueber die sogenannte Sanduhrform der Augite. — Jos. Blumrich, in Mi'n. Afitth., xiii., 239-255, 1893. The peculiar ** hour-glass " figure shown between crossed nicols by many augite crystals from the more recent eruptive rocks. Diopsid von Achmatowsk. — K. Busz, in Zeit, f. Kryst., xx., 558, 1892. Pyroxene from volcanic rocks of the Island of Bonin. — ?74 'fHE QUARTERLY, Y. Kikuchi, \v\ /ourn. ColL ofSc. Imp. Univ. Japan ^ 1889, vol. iii.^ p. 67 ; abs. in Zeit, f, Kryst^ vol. xx., p. 287, 1892. (Quartz. Elektrische Eigenschaften des Quarzes. — ^VV. C. Rontgen, Ann. d, Phys, N. F„ 59, 16 10 24, 1890; abs. in Neues Jahrb. Min., Ref. 1892, 214. Md^moire siir diverses fornnes affect^s par le riseau fel6mentilre du quartz. — M.Levy and Munier-Chalmas, in Bull.Soc, Min.y xv., i59-i9ii July, 1892. A study of the fibrous Sip, of which Chalcedony and the allied materials, quartzine and leuticine, are fornns. SCHEELITE, Scheelit aus Neuseeland. — A. Gurit, in Sitz,-Ber. neiderrheuK Ges, f, Natur.'U, Heilk.^ Bonn 1.S88, S. 23; abs. mZeit, /. Krysty vol. xx., p. 524, 1892. SCORODITE. Skorodit von Lolling. — K.Busz in Zeit. f, Kryst^ xx., 555-55 7r 1892. Serpentine. On the occurrence of an Aluminous Serpentine (Pseudophyte) with flint-like appearance near Kynance Cove. — Howard Fox in Minerahgical Magazine , ix., 275-277, December, 1891. Records analyses from four localities. SlDERlTE. Ueber kobalthaltigen Eisenspath von der Grube Hartebornthal bei Neunkirchen. — G. Bodlander, in Neues Jahrb, Min., 1892, IL, 236. Silver. Silver in volcanic dust. — J. W. Mallett, in Proc, Roy, Sac, 1890, vol. xlvii., 277 ; abs. in Zeif, f. Kryst,^ vol. xx., p. 515, 1892. Skutterudite. Tesseralkies aus den Alpen. — L. Standenmaier,in Zeitf, Kryst^ vol. XX., p. 468, 1892. Soda Microcline. From the Yellowstone Park. — ^S. L. Pen field, Seventh Rep, U, S, Geo/, Sur,y Wash., 1888, p. 267; abs. in Zeit. f, Aryst,, vol. xx., No. 3, p. 286, 1892. Sphalerite. Zinc-bearing Spring Waters from Missouri. — W. F. Hillebrand, in Amer. Jour, Sci,y 3d, xliii., 418-422, May, 1892. Stannite. Stannite and alteration products from the Black Hills, S. D. — •W. P. Headden in Amer, Jour. Sci,, 3d, xlv., 105-110, February, Including a so-called new mineral, Cuprocassiterite. INDEX TO MINERALOGICAL LITERATURE. 175 Stephanite, Etc. Mineralogische Notizen. — V. v. Zepharovich, No. xi., Nat.- ttnss, Jahrb.^ Lotos ^ 1889; abs. in Zeit. f. Kryst,^ vol. xx., p. 292, 1892. Minerals mentioned: pyroxene, rutile^ garnet, pseudo-stephanite. « Sulphur. Schwefel von. Allchar in Macedonien. — A. Pelikan, in Miti, Mitih,^xi\.y 344, 1892. Small crystals on stibnite. Crystallographic examination includ- ing new face (122). Schwefel von Roisdorf bei Bonn; Schwefel von Milo ; Schwefel von Bassick, U. S. A. ; Schwefel von Concil bei Cadiz, Spain. — K. Busz, in Z^//. /. Kryst,, xx., 558-566, 1892. Talc. Rose-colored lime and alumina-bearing variety of Talc. — W. H. Hobbs, in Amer, Jour. Sa',, xlv., 404-407, May, 1893. Thaumasite, Etc. Mineral analytische Mittheilungen aus dem Chem. Lab. der Univers., Upsala. — O. Widman, in Geo/. F'dren. Fork., 1890, vol. xii., 20-29 ; abs. in Zeit. f, Kryst.^ vol. xx., p. 373, 1892. Thaumasite, wollastonite, chabazite, vesuvianiie. -^ Thenardite, Etc. Mineralien und Pseudomorph. des Roseneggs. — A. Leuze, ip Jahresb. d. Ver. f. vaterl. Naturk, i. Wiirtt,^ 1889, 305 ; abs. in Zeit. f. Krysty vol. xx., p. 303, 1892. Minerals mentioned : gypsum, thenardite, glauberile, argonite, anhydrite. Pseudomorphose von Thenardit nach Glaubersalz. — A. Pelikaji^ in Mm. Mitth,^ xii., 476-482. Topaz. Neue Formen am Topaz. Ilmengebirge, Slid Ural. — L. Souhpur, in Zeit, f, Kryst.y vol. xx. p. 232, 1892. Natural Etching on Topaz of San Luis Potosi, Mex. — Min. Mitth.y xi., 331-348, 1893; abs.NeuesJahrd. Min,^ 1892, L, 506 Ref. Tourmaline. Ueber die Formel der Turmaline. — A. Kenngott, Neues Jahrb, Min.y 1892, IL, 44. By study of 44 analyses reaches conclusion that they all corres- pond to isomorphous mixtures of two silicates 3RjO.Si02 + 5 (R, OjSiO,) and 2 (3RO.SiO,) + R,0,.SiO, and that the red tourma- line of Rumford, Maine is practically the first silicate while as yet no analysis has been made which closely approaches the other. Tysonite, Etc Tysonite, Bastnasite, Meteoric Iron from Va. Anatase (Calif.) and Sapphire (Mont.). — Geo. F. Kunz, in Mineralogical Magazine^ ix., 394, December, 1891. 176 THE QUARTERLY. Vesuvianite. Studien uber den Idokras vom Vesuv. (Monte Somma) BolUtino delta Societa del Naturalisti in Napoli^ 1890, I., 173. — Abs. in Zeit, f. Kryst^y XX., 616, 1892. Krystallographische Beobachtungen am Idokras. — ^J. Boecker, in Zeit. f, Kryst,^ vol. xx., p. 225, 1892. Vesuvian-Pyroxenfels vom Piz Longhin. — Fr. Berwerth, Annal. k, k. Nat,' Hist, y HofmuSy 1889, ^o^- '^-j P» ■^7- — Abs. in Zeit. f. Kryst,, vol. XX., p. 291, 1892. Water. J Plasticity of Ice crystals. — J. McConnel, in Proc. Roy. Soc, 1890. vol. xlviii., 259; abs. in Zeit./. Kryst.y vol. xx., p. 515, 1892. WiLLEMITE. Willemite as slag mineral. — W. M. Hutchings, in Geolog. Maga- zine, 1890, vol. vii., 31 ; abs. in Zeit. f. Kryst.y vol. xx., p. 518, 1892. WURTZILITE. Wurtzilite. — W. P. Blake, in Eng, Mining Journ., December, 21, 1889 ; abs. in Zeit. f. Kryst.y vol. xx., No. 5, p. 492, 1892. ZlNClTE. Zinkitkrystalle von Franklin, N.J. — P. Grosser, in Zeit./. Kryst.y vol. XX., No. 4, p. 354, 1892. ^INNWALDITE. Zinnwaldite in the Granite of the Mourne Mountains. — W. J. Sollas, in Froc. Roy. Irish Acad.y 1890, vol. vi., 379; abs. in Zeit. / Kryst.y vol. xx., p. 519, 1892. Zircon. Ueber kunstliche Darstelling des Zirkons auf nassem Wege. — K. V. Chrustschoff, Neues Jahrb. Min.y 1892, II., 232-235. ZuNYiTE, Etc. Mineralogical Notes. — S. L. Penfield, Amer. Jour. Sci.y xlv., 396-399, May, 1893. Zunyite of Ouray Co. Col. Xenotime of Cheyenne Mt., Col. II. — Crystallography. Zwei Theorien der Krystallstructur. — L. Sohncke, in Zeit. /. Kryst.y vol. XX., p. 445-467, 1892. Beitrage zur Kenntniss der Beziehungen zwischen Krystallform und chemischer zusammensetzung, II. — A. Fock, in Zeit./ Kryst.y vol. xx., p. 434-444, 1892. Bemerkungen zu Herrn Fock's Aufsatz "Beitrage zur Kenntniss der Beziehungen zwischen Krystallform und chemischer Zusammen- setzung." — F. Becke, in Zeit. f. Kryst.y vol. xx., p. 253, 1892. Bemerkung zu dem artikel des Herrn E. von Fedorow, Die zusam- I I INDEX TO MINERALOGICAL LITERATURE. 177 manstellung seiner krystallographischen resultate und der meinigen l>etreffend. — A. Schoenflies, in Zeit. f, KrysL^ vol. xx., No. 3, p. 259, 1892. Zur Isomorphiefrage in der Dolomitreihe. — ^J. W. Retger and R. Braiins, in I^eues Jahrb, Min., 1892, I., 210-217. Solution and Crystallization. — G. D. Liveing, in I. and II., Cambr, J^hiL Trans., 1889, 14, and III., 1890, 15 ; abs. in Zeit f, Kryst, vol. XX., p. 510, 1892. Notes on Crystallites. — Frank Rutley, in Mineralogical Magazine^ vol. ix., 261-271, December 1891. A brief discussion of forms and a plate with 43 figures. Zwei Hiilfsapparate zum Goniometer. — V. Goldschmidt, in ZeiLf. JCryst., vol. xx., p. 344, 1892. Apparatus for showing Crystal Forms. — R. J. Anderson, in PhiL Mag., 1889 (5), vol. xxviii., p. 127 ; abs. in Zeit. /. Kryst, vol. xx, p. 284, 1892. Aufgaben der stereographischen Projection. — E. von Fedorow, in Zett,/. Krysi.^ vol. xx., p. 357, 1892. III. — Chemical Mineralogy. Versuche iiber die Loslichkeit einiger Mineralien. — G. A. Binder, in Minn. Mitih.^ xii., 332-343, 1892. The finely powdered minerals were placed in glass tubes with distilled water, or water containing CO,, the end of the lube closed by being melted together, and the tube placed in a water bath and kept at a fixed temperature for several weeks. Zur mikrochemischen Untersuchung einiger Minerale. — J. Lemberg, in Zeiisch. d. deutschen geoL 6r^j„ 42, 1890, 737 ; abs. in Neues Jahrb. Aftn., 1892, II., 7 ref. Rapid Qualitative Examination of Mineral Substances. — A. J. Moses and J. S. C. Wells, School of Mines Quarterly, xiv., 25-39, Novem- ber, 1892, zxidjourn. Anal. Chem.^ vii., 154 to 164. Bemerkungen uber einige Reactionen zum Bestimmen der Mineralien. Konst. Thaddeef, in Zeit.f. Kryst., vol. xx., p. 348, 1892. Action of HjSO^ upon natural oxide of manganese. Dioptase ; gypsum; Cobalt-carrying minerals. Verhalten der Silicate im Phosphorsalz. — K. Haushofer, in Sitz-Ber. //. Math.'Phys. Akad. d. Wiss., 1889, vol. xix., 8 ; abs. in Zeit.f. Krysi.^ vol. XX., No. 3, p. 304, 1892. Ueber das Verhalten der Titansaure gegen Phosphorsalz vor dem Lothrohr. — R. Brauns, in Is! eues Jahrb. Min,, 1892, II., 237. Production of crystals Ti^Oj. Formation of Minerals in Slags and Lavas Compared. — ^J. H. L. Vogt, 178 THE QUARTERLY. in Afchiv f. Math, og Naturwid^ xiii., 310, and xiv., 11 ; abs. in Min- eralog. Mag., x., 33, July,i892. Ueber die Synthese der Minerale der Hauyn-Gruppe,— J. Morozie- wiez, Neues Jahrb, Mm., 1892, II., 139-141. IV. — Physical Mineralogy. Note siir la Propagation de la Chaleur dans les corps Cristallisds. — Ed. Jannettaz, Bull. Soc. Min,, xv., 133-144, June, 1892. Researches on seventy-one species. Ueber die Umanderungen, welche die Zeolithe durch Erwarmen bei und nach die Triibewerden Erfahren. — F. Ruine, in Sitz. d. k. Freuss. Akad., November, 1890, 1 163-1207 ; abs. in Neues Jahrb, Min,, 1892, II., 237 Ref. Ein billiger Erhitzungsapparat fiir mikroskopische Praparate. — A. Schrauf, iii Zeit. f, Kryst., vol. xx., p. 363, 1892. Devitrification of Cracked and Brecciated Obsidian. — Grenville A. J. Cole, in Mineralogic a I Magazine, ix., 272-274, December, 1891. Based on examination of a Lipari lava. Krystallrefractometer vereinfachter Form. — S. Czapski, in Neues Jahrb, Min,, 1892, I., 209-210. V. — ^^Optical Mineralogy and Petrography. Recherches sur les variations des spectres d*absorption dans les cristaux. — H. Becquerel, in Ann, Chim, Phys, (6), xiv., 170 and 257, 1889; abs. in Neues Jahrb, Min,, 1892, II., i Ref. Die Optischen Anomalien der Krystall. — R. Brauns, in Neues Jahrb, Min,j 1892, I., 198-209. Sulla determinazione delle proprieta ottiche dei cristalli mediante tre prismi di orientazione qualunque. — Guiseppe Bartalini, in Gior. di Min., iv., 145-15 1, 1893. Eine neue Method der Optischen Untersuchung von Krystallplatten in Parallelem Lichte. — E. v. Federow, in Min, Mitih., xii., 505-509, 1892. Ueber die Zonarstructur der Plagioklase. — Richard Herz, in Min. Mitth,, xiii., 343-348, 1893. The Optical Indicatrix and the Transmission of Light in Crystals. — L. Fletcher, in Mi neralogical Magazine^ ix., 278-388, December, 1S91. A discussion of the behavior of light in crystals under the theories of compressible and incompressible ether. Methods of Modern Petrography. — Lea McI. Luquer, in School of Mines Quarterly, xiii., 357-364, July, 1892. Cutting and Grinding Machine, with illustration. — G. H. Williams, in Amer, Jour, Sci,, 3d, xiv., p. 102, February, 1893. INDEX 10 MINERALOGICAL LITERATURE. 179 VI. — Sundries. Mineralien des Miinsterthales. — A. Schmidt, in Geol. des Miinster- thales tm badischen Schwarzwaide^ iii., Th. Erzgange und Bergbau, Heidelb., 1889; abs. in Zeit.f, Kryst,^ vol. xx., p. 300, 1892. Mineralogisch-Geologisches aus Tarapaca in Chile. — C. Ochsenius, in Zeiti. d. d, geol. Gesselsch.^x^^^, vol. xli., p. 371 ; abs. in Zeit.f. Kryst,, vol. XX., p. 299, 1892. Mineral from Montgomery County, Md. — A. C. Gill, in Zeit,f, Kryst.^ vol. XX., p. 285, 1892. Contribution to Mineralogy of Maryland. — G. H. Williams, in Johns Hopkins Univ. Circ. 75 ; abs. in Zeit ./ Kryst,y vol. xx., No. 3, p. 285, 1892. Ueber ein Mineral der Noseau-Hauyn-Gruppe im Elaolith syenit von Montreal. — A. Osann, in Neues Jahrb. Min., 1892, I., 222-244. Mineralchemische Mittheilungen. — J. Loczka, in Math, und Naturw. Btrichie aus Ungarn^ 1890, vol. viii., 99-112; abs. in Zeit, f. Kryst, vol. XX., p. 317, 1892. Mineralogische Mittheilungen ausdem Siebenburgischen Erzgebirge. — J. Budai, in Orv. Term. Tud. Erfesits, 1890, vol. xv., 31 1-3 14 ; abs. in Zeii. f. Kryst.y vol. xx., p. 316, 1892. Mineralogische Mittheilungen aus Siebenbiirgen. — A. Koch, in Orv, Term. Tud. Ertesits^ 1890, vol. xv., 140-154; abs. in Zeit. /. ICrys/.^ vol, XX., p. 313, 1892. Beitrage zur Chemischen Kenntniss einiger Gesteine und Mineralien Corsikas. — E. Rupprecht, in Zeit. f. Kryst.^ vol. xx., p. 311, 1892. Barytabsatze einer Soolquelle. — G. Lattermann, in Jahrb, d. k,pr, Geof. Laudesufisty 1888, p. 259 ; abs. in Zeit, f, Kryst,^ vol. xx., p. 301, 1892. BULLETIN OF ALUMNI AND COLLEGE NEWS. The President's Annual Report is of unusual interest and from it and Official Bulletin No. VI., the following facts, of especial interest to graduates of the School of Mines, have been clipped. Changes in the School of Mines. The year in the School of Mines has been marked by very import- ant changes in the organization of the Departments of Engineering and of Chemistry. The death of Prof. Trowbridge made the former neces- sary, and the resignation of Prof. Waller led up to the latter Two years ago, the Department of Mining was set apart and placed under the charge of Prof. Monroe, who had been, up to that time, adjunct professor of mining engineering. All the branches of engi- neering proper continued to be under the oversight of Prof. Trow- bridge. This system produced unity at the top, while, in fact, the in- terests that are common to all of these branches are to be found at the bottom It was clear to the Faculty, however, that the death of Prof. Trowbridge made it desirable to reorganize the department completely, rather than simply to fill the vacant chair. There was no difference of opinion as to the common foundation that underlies all the branches of engineering. It is clearly to be found in mathematics and in mechanics developed from the mathematical point of view. . . . The necessary instruction in mathematics was already well provided for. The death a year or two earlier of Prof. William G. Peck, who had been the principal instructor in mechanics, had left that department also in a position where it could be considered in connection with the engi- neering problem. It was accordingly determined to create a chair of mechanics which should give to all the engineers so much instruction in the theory and application of mechanics as is needed by all. The chair of engineering was abolished and a professorship was established in civil engineering, in mechanical engineering, and electrical engineering. This organization permits of the freest possible development of each specialty after the point of common instruction has been passed. Mr. R. S. Woodward, C.E., a graduate of Michigan University of the class of 1872, was appointed professor of mechanics with the understanding that he is to have charge of such instruction as may be needed in me- chanics not only in the School of Mines, but also in the School of Arts and in the School of Pure Science. Mr. Woodward's career since graduation has been almost entirely in the government service, latterly in the United States Coast and Geodetic Survey, and his stand- ing as a mathematician is well known Prof. William H. Burr, C. E., a graduate of the Troy Polytechnic Institute of 1872, was elected professor of civil engineering, coming to us from the Lawrence Scien- tific School of Harvard University. Prof. Burr has had much practice BULLETIN OF ALUMNI AND COLLEGE NEWS. i8l both as an instructor and in the 6e]d, and his reputation in both ca- pacities is high wherever he is known. The former adjunct professors of mechanical and of electrical engineering, Prof. Frederic R. Hutton and Prof. Francis B. Crocker, have been given deserved promotion to the full chairs of mechanical and electrical engineering respectively. In the Department of Chemistry, Prof. Elwyn Waller has hitherto been professor of Analytical Chemistry in charge of the Quantitative Labora- tory. In view of his resignation. Prof. Pierre de Peyster Ricketts, who has heretofore held the somewhat anomalous chair of professor of assay- ing, has now been made professor of analytical chemistry, and all the analytical laboratories, including that of assaying, have been put under his direct control, ** There have been also certain char.ges in the various courses of study pursued in the seven lines of required study for the prescribed courses. These changes have been made pursuant to a principle of moving back- ward into the first two years of the of the four covered by the full courses, all of those studies which ai« fundamental and prelitninary, so as to leave the latter years freer for drill and for the pursuit of those ap- plications of these principles which form so important a feature of technical education. An especial feature of interest is the movement to secure in the first two years of the Academic Department a special preparatory and general training designed to lead from the end of the Sophomore year in that department into the beginning of the Freshman year in the scientific school, thus securing in six years something of the humanities and letters upon which the special work of the .technical school can best be grafted." The Trowbridge Ffllowship. This fellowship is endowed with the sum of ^10,000 by the Alumni Association of the School of Mines. The money was raised by subscrip- tions from over 150 persons, alumni of the School of Mines, and others, and is intended as a memorial to the late Professor Wra. P. Trowbridge, in token of the personal affection of his pupils and associates, in recog- nition of his distinguished ability, and to commemorate his important services in developing and strengthening the courses of instruction in the School of Mines. The money is given subject to the following conditions ; The Trustees to guarantee that the net income of the endowment shall not be less than five per cent, per annum. The fellowship to be known as the William Petit Trowbridge Fellowship in Engineering. The fellow to be appointed on the recommendation of a committee to consist of the President, and the Professors at the head of the Depart- ments of Mining, Civil, Mechanical, and Electrical Engineering in the School of Mines. Committee to have power to add to their number, to ^1^ from time to time the conditions under which the fel- lowship shall be held, and to direct and control the work of the frl- lows. In case at any time for good and sufficient reasons the fellowship is not awarded, the income may be expended for the advancement or encouragement of engineering research as the said committee may de- termine. 1 82 THE QUARTERLY. The University Press. '^ Resolved, That the Trustees assent to the organization of a corpo- ration to be known as the "Columbia University Press'* .... and consent that such corporation use the title and imprint "Columbia University Press,*' upon the understanding that such permission shall be exclusive until revoked by the Trustees, and that upon the revoca- tion of such permission, the use of the title shall be discontinued.** The incorporation of the Press was affected on June yth, with the following incorporators: Seth Low, Francis B. Crocker, George M. Cnmmings, Brander Matthews, Richmond Mayo-Smith, Henry Fairfield Oiborn, Harry Thurston Peck, John B. Pine, and T. Mitchell Prudden. The objects of the corporation, as stated in its certificate, are : **To promote the study of economic, historical, literary, philosophical, scientific, and other subjects ; and to promote and encourage the publi- cation of literary works embodying original research in such subjects.'* The reasons ior this incorporation may best be understood" from the following extracts from a letter to the Trustees, " As a consequence of the development at Columbia of university work and university methods. during the last few years there is now pro- duced at the College by professors, instructors, and university students, a large amount of original work that is worthy of preservation, and which would, if the results were published with proper discrimination, reflect great credit both upon the authors and upon the College While the original work done by our officers and students offers, in many instances at least, a real contribution to knowledge, it is, never- theless, of such a technical or special character as to be often unaccep- table for commercial purposes to the general publisher We regard it as eminently desirable, that a ready means of publishing really meritorious works should be provided, and that the character and extent of the work done in the University should be made known through publications bearing the imprint, ' The Columbia University Press.* .... We propose to form a separate corporation, to be known as the * Columbia University Press,* the primary object of which shall be to provide for the publication of literary works embody- ing the original research of our professors and university students. .... No person shall be eligible to membership in the managing board unless connected with the College, either as a Trustee, or as a member of the Faculty.* ' Gifts to the College. The Treasurer has received the following sums: From the estate of the late President Barnard, From Joseph F. Lou bat for the Loubat Prizes, From James Gordon Bennett, for the Bennett Prize, From friends of the late Professor Trowbridge, on accoun of the Trowbridge Fellowship, .... From Joseph Pulitzer for the Pulitzer Fund, . From miscellaneous givers for miscellaneous objects.$7,507.24
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giving $250 a year to each of those whom he might select, in the' hope that this sum would be considered by the parents of the boy as a fair offset to his earnings The second difficulty was harder to solve. Owing to the peculiar organization of the public school system in Ne'w York, there are no high schools in the city. Boys who are grad- uated from the grammar schools go directly into the sub-freshman year of the College of the City of New York, but at the end of this sub-freshman year they are not able to enter into any other college of good standing in the country The recent agreement between Columbia College and the Teachers College seemed to offer a happy way to solve the problem. The Teachers' College, among its other schools for children, maintains a high school, into which the boys may enter when they are graduated from the grammar schools of the city. It is estimated that the interval of three years will suffice to fit them to pass any college exammation in the country. Mr. Pulitzer's gift to Columbia College of J 100,000 carries with it, on the part of Columbia, the obligation to pay for the tuition of not more than ten boys a year during the three years which must be passed at the high school. Any excess of income beyond what may be called for to meet this obligation is available for the general uses of the College. *' The scheme, as it now stands, therefore, seems to be thoroughly practicable. Mr. Pulitzer proposes to pay ^250 a year to ten boys during the period of their high school and college education — that is to say, for a perion of seven years. Should the ranks remain full, Mr. Pulitzer's outlay for this generous purpose would be Ji 7,500 a 1 84 THE QUARTERLY. year, in addition to his gift to Columbia College of {100,000. Under these circumstances, Columbia College very cheerfully assented to Mr. Pulitzer's proposition that such of the boys as might choose Columbia for their Alraa Mater should enjoy here the privilege of free tuition." Instructors and Students of Columbia College. Instructors. 1893-93. Professors, 51 Emeritus Professors, 6 Adjunct Professors, 17 Clinical Professors, ......... 6 Instructors, 19 Tutors, ........... 15 Assistants, 2J Curators 2 Lecturers, . 15 Director of Laboratories, ........' i Demonstrators, .......... 3 Assistant Demonstrators, 7 Clinical Lecturers, 3 Chiefs of Clinic, . . lo Clinical Assistants, 48 226 School of Law, School of Medicine, . School of Mines, School of Political Science, School of Philosophy, School of Pure Science, Less duplicates, Students. 1892-93. No. holding Without Percentage degree. degree. Total. of degrees. >03 166 269 38 251 403 654 48 61 323 384 16 79 85 164 48 63 57 120 5*5 2 3 5 40 559 1037 1596 62 190 252 School of Arts, . Coll. Course for Women, 497 847 Grand total. 1344 296 1641 36.9 The Library. '* The additions for the year were 19,797 bound volumes, of which 8732 were received from purchases or by exchange, and 11,065 by gift. During the year 705 different persons and institutions have presented books or pamphlets to the library ; the number of volumes presented to the library was 11,113; the number of pamphlets given, 4666. *' For the purpose of showing the rates of increase of the library, the number of books added during the past six years is given as follows : BULLETIN OF ALUMNI AND COLLEGE NEWS. 185 1887-1888, 5,807 i888-i889» 8,502 1889-1890, . . . . • 14,^25 1890-1891, ' 16,440 1891-1892, 15,408 1892-1893, 19,797 "The number of bound volumes in the library, exclusive of pamph- lets, duplicates and collections deposited here but not the property of the college, is, approximately, 160,000 volumes. '* The number of books loaned from the library for use at home was 28,184. An extension of time was asked on 15,958 of these loans: The record for the past six years of loans is as follows : 1887-1888, 12,615 1888-1889, 11,325 1889-1890, 16,004 1890-1891, . . . 22,721 1891-1892, 26,632 1892-1893, 28,184 ** These statistics show a constant and healthy growth. '* The library is kept open, as usual, from 8.30 a.m. until 1 1 p.m. dur- ing term time, and during the summer vacation until 10 p.m. "Several hundred volumes of pamphlets have been carefully cata- logued and placed on the shelves during the year. This work, which in every large library accumulates to an alarming extent, we purpose to prosecute from year to year." Department of Architecture. The third competition for the Columbia Fellowship in Architecture began on the 28th of last December, by the issuing of a circular to all the alumni of the Department, announcing the subject of the competi- tion to be " A Monumental Gateway to constitute the principal exter- nal feature of a large College building.' ' On Saturday, January 20th, the contestants, fifteen in number, came up for the twelve-hour sketch, for which a supplementary and more detailed programme was handed to each one on his arrival. The final drawings, based upon these sketches, are to be handed in on March loth. The winner receives a scholarship of ^1300 to be spent in foreign study. Mr. H. B. Mann, the winner of the second competition, held in 1892, has just returned from Paris. The Department has received from the Department of Works of the Columbian Exposition the very valuable gift of a complete set of work- ing drawings of the Fair buildings, as one of the results of the visit made to Chicago in December by Prof. Sherman and Mr. Snelling, thanks to the liberality of Mr. Schermerhorn. Other acquisitions are expected. Prof. Hamlin announces a travelling class for architects desiring to study systematically the Italian Renaissance from the original monu- ments. It will be under his personal direction, and will start from Naples about June 7th, traveling northward to Rome, Florence, Siena, VOL. XV.— 13 i86 THE QUARTERLY. Venice, Verona, Milan, Genoa, and intervening points of interest; spending from a day to a week in' each of the places of minor impor- tance, with f¥om two weeks to a month each in Venice, Florence and Rome. The experiment of such a class has never been before attempted, and its result will be looked for with interest. A number of third-year and fourth-year students in the Department are expecting to join the class, and applications have been received from several alumni and from architects in Ohio and Illinois. The circular is pub- lished on another page. The lecture in French by Prof. Despradelle of the Department of Architecture of the Massachusetts Institute of Technology, on ** the Buildings of the World's Fair and the principles of architectural com position ** was greatly appreciated by those whose knowledge of French permitted them to understand it. The criticisms were not unsympa- thetic, arvi were very interesting as expressing the views of a large- minded and cultivated French architect. A Travelling Class in Architectural History. The following circular sent out to all the alumni of the Department of Architecture, has been handed us for publication : New York, December 28, 1893. Dear Sir : During the summer of 1894, the undersigned proposes to conduct a travelling class in architectural history, for the systematic study of the Italian Renaissance from its monuments. It is intended to spend be- tween three and four months in Italy, following a carefully prepared programme, of which the main outlines are given below, and further details of which will be given out in due time. This programme is made out, with reference not only to a profitable survey of the different historic phases of the Italian Renaissance, but also to the exigencies of the Italian climate, and to a reasonable economy in the manner of covering the large territory to.be gone over. It was at first intended to ii]^lude the French Renaissance in the pro- gramme of study. But as soon as this programme was laid out in detail it became evident that this would necessitate either going over the ground so hurriedly as to make serious study impossible, or leaving out of the itinerary important monuments and architectural centres, the omission of which would greatly impair the educational value of the trip. A sketch of the proposed itinerary is given on another page. The class will be restricted to twelve, or at most fifteen members, and is intended for such men as have already a fair equipment of architec- tural knowledge and experience, and are prepared to profit seriously by this opportunity for architectural and historical study. Advanced students and graduates of architectural schools, professional draughts- men and such others as can advantageously devote themselves to a criti- cal study of the actual works of the Renaissance, will be especially wel- come to its membership. Each member of the class will receive, as early as may prove practica- ble, an outline itinerary and a list of the chief monuments to be studied, BULLETIN OF ALUMNI AND COLLEGE NEWS. 187 and of the authorities to be consulted for each period, district or group of monuments. This will afford an opportunity for preparation on the salient facts of the history of these monuments, and for suggestions or criticisms regarding the details of the itinerary. Illustrated public talks will probably be given at Columbia College during the winter or spring, covering the same general ground. The undersigned will assume no financial responsibility for, or control over the expenses or individual movements of the members of the class, each of whom may take such conveyances, trains, lodgings and board as he pleases ; but he will co-operate with and assist any and all in making their arrangements. The class will meet at Naples early in June, 1894, and follow as nearly as practicable the proposed itinerary, radical modifications of which will be made only by general consent of the class. The class- work will consist not only of visiting and examining the monuments, but also of oral explanations and criticisms by the instructor, and reports, sketches and criticisms by the students, to be presented and discussed at informal meetings, in the course of the journey. The fees will be$150 for the whole trip; $125 for three months, and I90 for two months : payable$25 on subscribing ; ^25 on the first of
May, 1894, and the balance in equal monthly instalments.
The expenses of the whole trip, in addition to the class fees, will vary
according to the tastes of the members, from a probable minimum of
I500, to a maximum of |i2oo or over. This is estimated on a basis of
travelling second-class by all trains and first-class by all steamers, and of
an average daily expense for food and lodging, varying from $1.50 to J5.00 per day, with incidentals and sundries, averaging from 50 cents to$4.00 daily. It includes the transatlantic trip each way.
It is requested that those intending to apply for membership do so as
early as possible, in order to facilitate the organization of the class and
the determination of details as yet unsettled.
Correspondence is solicited with any desiring further information.
All applications should be addressed to the undersigned,
A. D. F. HAMLIN.
Columbia College,
New York City.
OUTLINE OF PROPOSED ITINERARY.
The class will meet early in June at Naples, where a week will be
devoted to the Renaissance monuments, with side-trips to Pompeii,
Herculaneum, Capri, etc. Caserta will be visited on the way to Rome,
where the class will remain about four weeks. A week will be spent on
the way from Rome via Spoleto, Foligno, Perugia and Arezzo to
Florence, which will be the centre for four weeks of study, including
visits to Sienna, Pisa, Lucca and Pistoia. Three or four weeks will be
devoted to Bologna, Ferrara, Padua and Venice, the balance of the
available time being devoted to Vicenza, Verona, Mantua, Brescia,
Milan, Pa via and Genoa.
If the class can start so as to be in Naples by the 7th of June, they
may safely engage return passage by steamers due in New York early in
October.
BISHOP CfUTTA-PERCHA COMPANY,
INSVLATBD WIRES AND CABLES,
4SO-426 EAST 26th STREET, NEW YORK CITY.
Crosa-seclion of (.':
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use cables of our design and manufacture.
HENRY A. REED, See. and Manager.
WOODBRIDGE SCHOOL,
FORMERLY
School of Mines Preparatory School,
Between 48th and 49th Sts., NEW YORK CITY.
A HIGH SCHOOL,
INTRODUCTORY TO ALL COLLEGES.
J. WOODBRIDaE DAYIS. C.E., Ph.D,
'^:RXisrGX's>j^Tj.
Twelfth Year Begins October 2, i8gj.
Four hundred Students of Columbia School of Mines have been
instructed in the Woodbridge School.
Also a large number have been prepared for Massachusetts Institute
of Technology, Stevens Institute, Sheffield Scientific School, Troy
Polytechnic Institute, Cornell University, and the Classical, Medical
and Law Departments of Harvard, Yale, Columbia and Princeton.
Vol. XV. No. 3. APRIL. 1894.
THE
SCHOOL OF MINES
QUARTERLY.
A
JOURlf AI^ OF APPLrlHD SCIB^CH.
*■>
BOABD OF EDIT0B8.
A.J. M08ES, Adj. Prof, of Mineralogy. E. WALLER, Analytical Chemist.
J. F. KBMP, Prof, of Geology. J. L. GREENLEAF, Adj. Prof. Civil Engineer'g.
R. PE£LE, Jr., Adj. Prof. Mining. JOS. STRUTHERS, Tutor in Metallurgy.
Managinsr Editor, A. J. MOSES.
CONTENTS:
Engineering itotes on Irrigation Canals. By W. Newbrough 189
Simplified Method for Obtaining the "Axial Cross '* of Any Crystal
from Any Projection of the Isometric Axes. By Alfred J. Moses ai4
A Peruvian Salt Mine. By Robert Peele, Jr 219
Catallel, Metallel, SynalleL By A. D. F. Hamlin 222
Details of Modern Water- Works Construction. By Wolcott C. Foster, 230
Contributions from the Analytical Laboratories of the School of Mines,
Columbia College — Schemes for Qualitative Analysis. By J. S. C.
>VeUs, Ph.D., and A. R. Cushman, Ph.D 244
Abstracts 275
Book Reviews 282
COLUMBIA COLLEGE.
NEW YORK CITY.
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All Remittances should be made payable to Order of " The School of Mines Quarterly.**
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FILES AND RASPS^
Of SUPJSBIOM QUALIXT.
We make
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THE
SCHOOL OF MINES
QUARTERLY.
Vol. XV. APRIL, 1894. No. 3.
ENGINEERING NOTES ON IRRIGATION CANALS.
By W. NEWBROUGH.
The object of this paper is to treat of the particular portions of
the work in the survey and construction of an irrig-ation canal
that concern the young engineer. Therefore, those parts which
require experienced engineering skill and financial ability, such as
the construction of large weirs, the selection of proper irrigable
lands and the business management will not be considered.
A preliminary survey will first necessarily be made, for the pur-
pose of ascertaining the grades on which the water will be carried
from the source of supply to the designated tract of land which is
to be irrigated.
For this a level should be used, although, if great care is ex-
ercised and the grade is not too gentle, a transit with a long
bubble may be employed. The rod should be self- reading and
graduated to tenths or half-tenths of a foot. Pacing will generally
suffice for the measurements. Two or three men beside the
engineer comprise the party. If possible, a team and wagon
should accompany the surveyors ; thus time is saved in going to
and from work, and the wagon can carry stakes, tools, etc., during
the day.
If a start can be made from the head of the canal, the rodman
should hold the rod in the stream at the bottom. The reading
should be taken, say it is 8.8. The rodman now comes to the
bank where the headgate is to be placed and holds the rod, say it
VOL. XV. — 14
I90 THE QUARTERLY.
is 4.2. Hence the cut at that point will be 4.6. It is best to
assume a grade. Suppose the grade to be 0.1 foot per loo feet,
and also assume that the canal is to be cut 4 feet below the
natural surface of the ground on the lower side. The next rod.
100 feet beyond the edge of the bank, should then read 8.8 — 4.2
= 4.6 + 0.1 = 4.7 feet. At station 2 it should be 4.8 ; at station
3 = 4.9, etc.
The rodman paces off lOO feet beyond station o on the bank,
and holds the rod. The instrument man now moves him to the
right or left until the rod reads 4.7, or if this is impossible, the
cut is marked on the stake and the rodman goes on until he finds
a place where the reading coincides with that which is required.
At this point a stake is driven and marked thus, '* 4, cut 4 ft. O.K."
Stakes subsequent to this, which are set 4 feet above the bottom
of the canal, are merely marked with the number of the station.
All the above points are entered in the field-book as follows :
Su.
Cut.
4.6
I
4.9
2
4.4
3
4.5
4
4.0 OK
5
• • •
O.K. being the symbol that shows the required height is
reached.
Sometimes it is necessary to build a dam across the stream in
order to cause the water to enter the canal. When this is the
case, the point to which it is required to raise the water is noted,
the depth of the canal subtracted and the survey proceeded with
in the same manner as before.
The rodman now goes forward from one to five hundred feet at
a time, according to the ability of the leveller to see him, and
moves to the right or left as directed, and stakes are driven at the-
points where he stops and numbered according to distance.
Thus: successive stakes might be 0-1-2-6-10-1 2-16, according
to the amounts paced off between them, 400 feet being the dis-
tance between 12 and 16.
These points are turning points, and the turn is made on the
ground. My own practice is to turn on the right hand side of the
-^ immediately at the foot of the same.
NOTES ON IRRIGATION CANALS, 191
Bench marks should be put in least every 1500 feet. These
may be on trees, rocks in place, or on stakes driven at least one
foot in the soil and extending not more than two inches above the
surface, with a witness stake alongside.
It is not advisable to take -sights over 500 feet in length each
way with a self-reading rod, and 400 feet is better. If a target
rod is used and the rodman understands the work, 8do feet may
be taken on a preliminary survey when the grade is not less than
0.1 foot per 100 feet. Care should be taken to have the back-
sights and fore-sights nearly equal in length.
The method of work outlined above does away with volummous
notes, as the number of the stake multiplied by the fall per station
of 100 feet gives its height below the head of the ditch. The
position of the bottom of the rod is always known. In the case
cited it is 4 feet above the bottom of the canal.
Hence after having set up the instrument and read the rod, it is
only necessary to add the fall per station to the reading for every
100 feet the rodman moves.
Thus if the back-sight at station 17 is 5.1, at 18 it will be 5.2,
at 19, 5.3, etc. There is less liability to error in this method than
if regular section-level notes are used. The notes being headed
with the date, cut below the natural surface and the assumed
grade, only show the numbers of the stakes used, except where
there is an extra cut, fill or change of grade, when the fact is
mentioned.
If the assumed fall is found to be too great, a lesser one can be
chosen, and the last stake moved up on higher ground to its new
position and the survey carried on from this point. As above,
station 17 is 1.7 feet below the head. If we reduce the fall to 0.5
feet per 100 feet, we would have fallen but 0.85 feet ; hence we
can move stake 17 0.85 feet higher. Note this fact in the
field-book. The reverse of this proceeding occurs when the grade
is too slight. We make this change on the assumption that the
length of the line will not be materially affected, and generally
such will be the case.
Frequently it is necessary to cross a divide which affords a
governing point, usually its lowest.
This is assumed or found by running level lines, and the canal
is ** backed in " to the head. This method may place the head
of the canal in a very unfavorable position if a uniform grade is
192 THE QUARTERLY.
run from the divide to the head. The grade can generally be
slightly cljanged for some distance so as to place the headworks
The location of the headworks is a factor of importance. Usu-
ally they are located where the stream is narrow and the adjacent
slope of the country is steep. In all but very small canals a weir
is built across the stream to divert the water into the canal.
The site should be chosen so that the headworks will cost a
minimum, and so that the length of the diversion line will be a
minimum. The diversion line is that part of the canal which
carries water from the head works to the land to be irrigated.
Canals should be so designed that the angle at which they are
diverted from the stream should cause the least deposit of silt
before the headworks. In other words, the back eddy in front of
the headgate should be a minimum. The ideal position is to build
the weir directly across the stream, and to take out the canal at a
right angle to the weir. In this case the weir should be provided
better understood from the following diagram :
22^
I
^
Weirs are composed of brush and loose rock, loose rock, loose
rock and earth or gravel, loose rock logs and lumber, rectangular
piles and masonry.
Brush and loose rock barriers, or those composed of loose rock
alone, require no engineering skill tp be used in their construc-
tion.
Weirs composed of loose rock and earth or gravel may be of
large size, and require considerable calculation and study to obtain
the proper slope of the banks, and also to determine the size re-
quired. Care must also be taken in regard to the foundation and
the junction of the ends of the weir with the natural banks of the
stream.
NOTES ON IRRIGATION CANALS. 193
Those weirs composed of loose rocks and logs require a good
foundation, and consist of a crib-work firmly fastened together
placed upon the foundation. From the crest of this crib-work
planking extends backward up the stream, being set at an angle
from the top of the crib-work to the bed of the stream. On this
planking gravel should be placed. Such weirs are seen every-
where throughout the United States.
Rectangular pile weirs are used mostly in the west, and their
occurrence is confined to shallow streams which have a gentle
current. Eight or nine feet is about the limit of their height.
They consist of a double row of piling driven across the stream
and lined with sheet piles, the interior space being filled with
gravel.
Masonry weirs are generally constructed in connection with
large enterprises, and if of any considerable size require a high
degree of engineering skill and experience. Several good de-
scriptions of such weirs will be found in Mr. H. M. Wilson's
Irrigation Engineerings and to that book the seeker after in-
formation in this direction is referred. As far as possible the
grade in a canal should be kept uniform. However, in nearly
every case conditions will arise where it will have to be changed.
When this is done the cross-section of the ditch should be
changed and so proportioned that the canal will maintain a con-
stant velocity. The proper cross-section can be ascertained by the
application of Kutter's formula. This cannot be done, however,
when natural washes occur which run in the proper direction. If
they are well defined water courses, and of sufficient size to con-
tain the volume of water in the canal, it is perfectly legitimate to
use them. This remark applies to the diversion line only. When
natural channels are used the cross-section of the parts of the
canal which are excavated should be increased in size, because a
loss of water is incurred by their use, due to the absorption result-
ing from roughness of the channel and the stream becoming
shallow.
Experience and judgment alone can determine whether it is
better to carry a line around a low hill or to cut through it, or
whether to go around a long, gently sloping cafion, or to build a
fill across its mouth. In each case it is preferable to run both
194 > THE QUARTERLY.
lines, roughly estimate the amount of loose and solid rock* to be
encountered, calculate the relative cost, and then decide. This
calculation will of course be made from level cross-section tables.
I have known one or two cases where a fill was built across the
mouth of a canon under the mistaken impression that the water
backing up would form a small reservoir, the true fact being lost
sight of, viz.^ that the only available water stored was equal to the
area of the reservoir multiplied by the depth of the ditch, which
amounts to a very small quantity.
In the majority of cases, except where there is a certainty of
heavy rock work to be encountered, it is better to go around the
eafion on the grade contour, because fills, if of any height, with a
considerable amount of water pressing against them, require con-
stant repairs and attention, and should a break occur it \^ almost
certain to be disastrous.
Where a canal must cross several divides the general method
of preliminary surveying is to back the line in from each divide.
When taking it out of a natural wash, the most favorable place
is selected for a weir or dam, and the line started from this
point.
Both these conditions occur frequently in small canals, and
sometimes in those of considerable size. The Sheep Creek canal
in Utah crosses three divides, and utilizes seven miles of natural
wash in its twenty miles of length.
The diversion line should be as short as possible, as it is the
unproductive part of the canal. Any grade that the ground will
stand should be given if necessary. On the Del Norte canal in
Colorado the fall is 35 feet per mile through a rock cut, and on
many parts of its constructed diversion line the fall is 8 feet per
mile. This canal is 65 feet wide and 5^ feet deep. Smaller
canals could be given a heavier grade.
When the canal reaches the land to be irrigated, however, the
grade must be much reduced. For large canals 2 feet per mile in
sandy soil, and 33/< feet in ordinary soils is sufficient. For small
canals up to 35 feet in cross-section, 5 feet can be used when the
soil is firm. Heavy grades, if they do no other harm, cut the soil
and make it difficult to take out the laterals. As examples of the
relative sizes of grades, widths and depths, the following are
given :
NOTES ON IRRIGA TION CANALS.
195
Namr.
Area Watered.
Length.
Width of
Bed.
Depth.
Bear River Canal, Utah......
Idaho Mining and Irr. Canal
Calloway Canal, California..
Bear River and Yellow
Creek Canal, Wyo. (not
, completed)
Laterals, Unita County.Wyo.
200,000 acs.
350,000 "
80,000 "
15,000 •'
700 "
i5on)ls.
70 ''
32 "
20 "
X to I "
I in 5280
I " 2640
I *'66oo
«
I ** 1000
I " 750
50
40
80
16
4
7.0
xo.o
3.5
3.0
I.o
In the survey of a canal sharp bends are to be avoided. They
retard the flow and are dangerous to the canal banks.
A good topographical map of the country, with five-foot con-
tours, would be of great assistance in locating a canal, but com-
panies are usually unwilling to pay for work of this kind, and
such a map is unattainable otherwise, consequently nine times out
of ten the preliminary and location surveys are made in the man-
ner explained in this paper.
After the preliminary survey has been made and the amount of
land to be irrigated determined, the next step is to calculate the
cross-section of the canal.
Sometimes, when any desired grade can be obtained, the cross-
section is assumed and the grade determined according to its
dimensions. This state of affairs, however, is the most infrequent
of the two. The cross-section of a canal largely influences the
velocity of flow and the consequent quantity of discharge. Of
two cross-sections, that which has the least wetted perimeter will
give the greatest discharge. Hence the best theoretical shape is
the semi-circle, but as its construction is awkward and expensive,
a trapezoid is employed. From what has just been stated it would
seem that a rectangular ditch 10 feet wide and 2 feet deep would
be better in all cases than one 20 feet wide and i foot deep, the
former having 14 feet of Wetted perimeter and the latter 22 feet.
Also the evaporation and percolation would be less in the first
than the second. The respective discharges of the two, according
to Kutter's formula, taking n = .025, would be 44 second feet and
32 second feet. Providing the soil was all earth, the advantage
all lies with the first form, but should the ground be solid rock,
with a foot or foot and a half of soil on top, it might be advisable
196 THE QUARTERLY.
to shape the ditch according to the second cross-section, even
though it were necessary to make it larger.
In other words, the material to be moved has an important
bearing on the shape of the cross-section, on account of the rela-
tive cost of excavating earth, gravel, cement, loose and solid rock.
It is because large canals have a less wetted perimeter in pro-
portion to their cross-section than small ones that they have a
greater velocity.
Before showing the method of calculating the cross- section, a
few definitions of the units employed in irrigation work will be
given.
A " second foot " is a cubic foot of water with a velocity of
one foot in one second. The carrying capacity of a canal is usu-
ally expressed in second feet. If it is necessary to expiess it in
gallons, multiply by 7^.
An " acre foot " is the amount of water that will cover one acre
one foot deep, or, it is 43,560 cubic feet. This unit is generally
employed in stating the capacity of reservoirs. One second foot
will make a little over two acre feet in 24 hours.
A " miner's inch " is the quantity of water that will flow
through an opening one inch square under a head varying from
four to twelve inches, in one second. Consequently the amount
varies, but is usually defined by State statute, 50 miner's inches
constituting a second foot in California and 38.4 in Colorado.
This measurement is used in mining work.
The ** duty of water " is expressed by the number of acres a
second foot will irrigate. This is a matter of doubt, and is at
present being investigated largely in the arid region. It is found
that when land is first irrigated it requires a greater quantity
of water than it does in subsequent years. The climate and
altitude also seem to affect the amount. The character of the
crop influences the duty, oats requiring much more water than
potatoes. Many of the western States prescribe a certain amount,
beyond which water rights will not be granted. Thus Colorado
and Montana prescribe 80 to 100 acres; Idaho and New Mexico,
60; Wyoming, 70; and Utah, 60 to 80. In India the duty
reaches from 200 to 300 acres, and with sub-irrigation it has gone
as high as 800.
When the amount of water necessary to irrigate a tract of land
is calculated some margin should be left. If the diversion line is
NOTES ON IRRIGATION CANALS. 197
long and no extra supply is received into the canal from side-hill
drainage or from streams other than the main one, a loss will
occur due to evaporation and percolation. In a new canal this
will amount to from 25 to 35 per cent, of the water entering the
headgaie. The cross- section of the canal should be increased
accordingly.
Kutter's formula may be employed to calcjulate the cross-section.
It is expressed as follows :
r 1. 81 1 ^ .00281 ^
+ 41.6 + — J— I
I + ( 41.6 + — .- ) X — ^ I
where v= velocity; « = a constant depending on the roughness
of the channel ;
. fall area of cross-section in square feet.
distance ' wetted perimeter in linear feet.
Various values of n are given :
.012 = unplaned lumber (flumes).
.017 = rubble,
.020 = canals in good order and regimen.
.025 = canals in moderately good order and regimen.
.030 = canals having stones and weeds.
.035 = canals in bad order.
.050 = torrents and natural washes in caiions.
Experience is necessary to judge what value of n to employ,
but it is advisable to take it rather high.
Tables have been evaluated for Kutter's formula for different
values of r and n. The one accompanying this article will be
found to answer nearly every case, and is taken from Johnson's
Theory and Practice of Surveying, When evaluated the for-
mula reduces to
v=- CV ri^
which is the Chezy formula. The value of r is deduced, n as-
sumed and C taken from the table.
This table is evaluated for i=- 0.00 1. The coefficient C changes
so slowly with a change of slope that the error does not exceed
3/^ per cent, if the table is used for all slopes from i in 10 to i
in 52.80, which is a foot to the mile.
198
THE QUARTERLY.
Table
giving Values of C in Kutter's .
Formula when i = o.ooi.
Values op «.
T in feet
•■in fr^t
.1
.oia
72.7
.015
53.2
.0x7
•44.6
.020
.0225
30.0
.025
.030
.035
_
16.3
r 111 l^^fc«
.1
35.5
25.9
20.1
.2
89.1
66.3
56.2
45.2
38.6
33.6
26.3
21.5
.2
■3
98.8
75.0
63.4
51.8
44.6
38.4
30.3
25.1
.3
.4
106.0
80.4
68.8
56.2
48.4
42.4
33.7
27.8
.4
.5
III. 2
85.1
72.8
60.0
51.8
45.4
36.2
30.0
.5
.6
115.7
88.8
76.4
62.9
54.5
48.0
38.5
32.0
.6
.7
"9.3
92.0
79.3
65.4
56.9
50.2
40.3
33.6
.7
.8
122.3
94.6
81.9
67.7
59.0
52.2
42.0
35.1
.8
.9
1 25. 1
97.0
84.?
69.7
60.8
53.8
43.4
36.3
.9
I.O
127.4
99.1
86.0
71.5
6^.5
5S.4
44.9.
37.7
1.0
1.2
>3i.5
102.7
89.4
74.5
65.3
58. 1
47.1
39.7
1.2
1.4
134.7
105.7
92.2
77.0
67.7
60.2
49.2
41.5
1.4
1.6
137.4
108.2
94.5
79.3
69.9
62.3
51.0
43.2
1.6
1.8
159.7
1 10. 3
96.6
81. 1
71.6
64.0
52.6
44.6
1.8
2.0
141.8
112.3
98.4
82.9
• 73.4
6S.S
54.0
45.9
2.0
2.2
M3.7
1 14.0
100.
84.3
74.7
66.9
55.2
47.0
2.2
2.4
145.3
115.4
101.4
85.6
76.0
68.1
56.3
48.0
2.4
2.6
146.8
1 16. 8
102.8
87.0
77.1
69.2
57.4
49.0
2.6
2.8
148. 1
1 18.0
104.0
88.2
78.2
70.3
58.4
49.9
2.8
3.0
149.3
1 19. 2
105. 1
89.3
79.2
! 71.3
59.2
50.6
3.0
3.4
151.4
121.3
107. 1
91. 1
81.0
73.0
60.8
52.0
3.4
3.8
153.3
123.0
108.8
92.7
82.5
74.5
62.3
53.5
3.8
4.2
155.0
124.6
1 10.3
94.3
83.9
1 75.8
63.5
54.7
4.2
4.6
156.4
125.9
III. 6
95.4
85.2
77.0
64.7
55.7
4.6
5.0
157.7
127.2
112.9
96.6
86.3
78.1
65.7
56.7
5.0
To illustrate the use of the table a case is assumed.
Amount of land to be irrigated, 10,000 acres.
Duty of water = 100 acres per second foot.
Fall of canal per mile = 5.28 feet; hence /= .001.
Loss by evaporation, percolation, etc., is balanced by gain from
extraneous drainage.
NOTES ON IRRIGATION CANALS. 199
Take n equal to .030.
— '■ = ICX) second feet are required.
100
Assume a cross- section 12 feet on the bottom, 18 feet on the
top and 3 feet deep. This has an area of 45 square feet and a
wet perimeter of 2]/9 + 9 -|- 12 = 20.486 feet. Hence, 45 -^
20.486 = 2.2 nearly = r. From the table, taking r equal to 2.2
and n equal to .030, we have C= 55»2, and consequently v =
55.2v''f7 = 55.21/2.2 X .001 = 2.49, and as Q =^Av or the ar^a
of the cross- section multiplied by the velocity, we have Q = Av
= 45 X 2.49= 112.05 second feet, while we only require 100.
Had we taken a cross-section 1 1 feet on the bottom, 17 on top
and 3 feet deep, the result would have been 105 second feet. The
nature of the soil, the fact whether natural washes occur and
various other external considerations will determine which of these
*
two it is better to use.
There are several other formulas given in works on hydraulics
and mechanics which maybe used, but Kutter's gives the best sat-
isfaction.
The cross-section of the canal having been determined and the
grade being known, the location on the ground follows.
The stakes on location should be large and long and set not
over 100 feet apart, in rough ground not over 50, and numbered
from o up, as in railroad work. Bench marks should be placed
every 1000 feet at least and «?et far enough away from the staked
line so as not to be disturbed by the construction of the canal. It
is a good plan to mark them somewhat a<: follows: " B.M. 3.12 ft.
above bottom of canal at Sta. 50, which bears S. 18° 45 E, 52.*
ft.'* They then serve not only as bench marks but as reference
points for the canal line as well. A good permanent bench mark
on a rock or large tree should be placed near the headvvorks and
fully described and entered in the field notes. It is well to write
on this bench mark itself, or on a witness stake near by, a full de-
scription of its position as " B.M. 4*** above bottom of canal at head-
gate. Headgate bears S. 48" 15 E. 129 ft. Sec. cor. to Sees.
4-5-8-9 bears N. 89° 10 W. 15 16 ft. Var. 16° 30' E."
Bearing objects should be taken from this bench mark, and, in
fact, if there is time, from all the bench marks.
The proper tools to use in running a location line are an
engineer's level, a 50- or lOO-foot chain and a Philadelphia target rod.
200 THE QUARTERLY.
The Philadelphia rod. in preference to the New York or Boston
one, because it can be used as a self-reading one on intermediate
sights.
Stakes should be set to the nearest half-tenth and turning points,
and bench marks to the nearest half- hundredth of a foot. Before
construction is commenced the line should be checked.
Turning points should be small pegs of wood, as in railroad
work, about one inch square and six inches long, and their posi-
tions should be noted in the field book.
The rodman should check the leveller on the turning points.
Six hundred feet each way is far enough to take sights. Care
must be taken to make the back-sights and fore-sights nearly
equal in length.
If water is plentiful, on side hill work the excavation is generally
sufficient to make the bank on the lower side, and the water is
allowed to back up against the hill on the upper side. In this
case the stake is really on the lower side of the canal, and not on
the centre.
The adjustments of the instruments should be tested daily.
The method of running the location level line is the same as
the preliminary, except that stakes are set every 50 or 100 feet
apart.
The level line is the most important part of the work on canal
location, and should be run with great care and attention. Unlike
railroad work a canal surveying party is generally small, consist-
ing of the engineer and three or four men. This party runs the
level line, the transit line, and the engineer takes the necessary
topography and makes the maps, and frequently attends to filing
the maps, notes and papers in the United States Land Office.
Before treating of the alignment of the located line a few pre-
liminary statements are necessary.
The United States Government, in its system of public land
surveys, allows the interior of a township to be run with a plain
compass with telescopic attachments ; in other words section lines
can be run with the needle.
The limit of error varies somewhat, but if the closing on a section
corner is within 50 links or 33 feet, it is generally considered good,
and will pass the Government examination. Therefore it is pos-
sible that a Government section corner, or quarter section corner,
may lie anywhere within 33 feet of its true position. Many Gov-
NOTFS ON IRRIGATION CANALS. 201
ernment surveys are very defective, especially those executed in
years gone by, before the Government sent out special examiners
of contracts.
It is not unusual to find the declination of the needle to differ
as much as three degrees from that given on the plats, and in the
notes and for the corner to be found from 1 to 200 feet from its
proper position. Wherever it may be. its position in the field is
fixed, and no person has a right to disturb it, except a special officer
appointed for that particular purpose by the General Land Office.
In ordinary country, with a good, sensitive needle, a line two
miles long (one mile north and one mile east), as surveys are run,
can be made to close much within the limit of 33 feet, and it should
close within ID or 12.
The act of Congress, approved March 3, 1891, entitled an "Act
to repeal the timber culture laws, and for other purposes," grants
the right of way through the public lands of the United States
for the use of canals, ditches and reservoirs heretofore or hereafter
constructed by corporations, associations or individuals upon the
filing and approval of the maps, notes and certificates. The right
of i way of a canal or reservoir is the land contained within 50 feet
of the marginal limits.
Should any changes be made in the construction of a canal, or
should errors be made in a survey which will not cause the canal
to fall outside the 50 foot limit, the survey will pass inspection and
be approved. In other words the limit of error in surveys of canals
is fixfed at 50 feet on each side of the marginal limits. For this
reason a survey of the canal can be run by the needle, and the
needle need not be read closer than fifteen minutes.
This is evident because the tangent of 0^15' = .00436, which
for one mile gives a distance to the right or left of 23.02 feet, which
in itself is well within both limits of error. The probability is that
not more than one-half this error would be made, and as a fact it
is generally considerably less, amounting to from 4 to 6 feet.
The canal could be surveyed by a transit and the angles read
by the plates, and under certain circumstances this might be ad-
visable. However, were this done it would be useless if the courses
were not measured with as great care as the angles, and to make
the survey consistent the angles would be numerous and the courses
exceedingly short. There are two reasons against this transit
method ; one is that the Government does not require it, and the
other that more men would be required on the survey.
202 THE QUARTERLY.
As the stakes have been set by the level wherever the grade line
of the canal caused them to be placed, the chances are that no
three stakes are in a straight line while fifteen or twenty may be
approximately so.
To overcome this difficulty and to make a survey of a canal,
the following method answers very well :
Beginning at the head of the canal, the head gate is tied directly
to the first bench mark and to the nearest section or quarter-sec-
tion corner by bearing and distance.
The two chainmen and an extra man, generally the axeman, are
then left at this point, which is Station O, the axeman standing
exactly over the stake. The instrument- man starts from this point
and walks along the line, taking care that no stake is more than
25 feet from the straight line joining himself and Station O. This
can be done very easily. The reason for setting large and high
stakes, which was mentioned previously, is now evident. If in
sage brush country, they should be high enough to be plainly
visible. In timber, much shorter courses will have to be taken
than in the open. Suppose the instrument-man stops at Station
6, as he notices a decided bend in the line at this point. He sets
up over stake 6 and reads the bearing and enters it in the notes as
read. He is really reading a reverse bearing, but it i$better to make changes afterwards in the office. It is a good principle in all kinds of surveying to enter in the note-book what is actually done in the field, and leave all changes to a subsequent time, never, however, erasing the original notes. The compassman then signals " all right," and the chainmen chain straight toward the instrument and give the engineer the distance when they reach it. The entry in the note-book appears thus : Sta. 6 to Sta. O— S. 54° 30' W. 591 feet. The axeman now takes his position over stake 6, the instrument- man goes to the end of another course, and the survey is carried forward. By this method the engineer selects the courses himself and does not trust to an inexperienced man. Compass stations, which are in the vicinity of bench marks, should be tied to them by course and distance, and then if de- stroyed during construction can be regained. If possible, always make a compass station at some even level station and not between NOTES ON IRRIGATION CANALS. 203 two of them, as at 6 + 53. 6 + 53 is not fixed, as the height of that particular spot is not known, and if the station is destroyed there might be some little trouble in finding it. If, however, we wish to recover Station 6, we have both the compass notes and its height from the nearest bench mark. It is also recommended that observations be taken to find the declination of the needle instead of trusting to reports or other information. As an example of the value of reports, I merely state that they generally declare the variation in southwestern Wyoming to be 17° 40' E., while from actual observations both myself and many others have never found more than 16° 35'. In finding the declination, any of the ordinary methods in use will do, but observations upon Polaris at either elongation or cul- mination seem to be slightly in more favor with the General Land Oflfice. Why this is, I do not know. Any of the various solar attachments will do good work. Buff & Berger, of Boston, manufacture a cheap one, the Davis screen, which is being used considerably. The method of using it and the subsequent calculation is ex- plained in their catalogue. If the sun's altitude is not too high, by fastening a piece of col- ored glass over the eye-piece with wax and pointing at the sun's disk, a very good observation can be made. Read the vertical angle and the horizontal angle between the sun and some fixed object. The calculation is then the same as is used for the Davis screen. Having obtained the variation, if the instrument has a variation arc it should be set off. As the survey progresses, the section lines and quarter-section lines^ are ** run in." At this stage of the survey the engineer will usually have a fair idea of the places where many of the corners are situated, and when he surmises that he is about crossing a government line he will go to the corner and run from it until he crosses the course on the canal and notes the distance on both lines. The entry is made in the note-book as follows : Sta. 48 4- 379 =511 S. of Cor. to Sees. 16- 17-20-21. Sometimes it will be necessary to re-run government lines in order to find the corner stones. If they are known to be well 204 THE QUARTERLY, placed, pacing will suffice to find them, and in open level country a wagon-wheel with a rag tied on it makes a splendid odometer. If the government survey is poor, it is best to use a chain and run according to the government notes if obtainable. Every effort must be made to find a corner before it is reported as not being in place. As soon as possible after the field-work is done the survey should be checked up, \Vith the aid of a traverse table, to see if the distances of the section corners correspond with the survey of the canal. It is a good plan to run part of the level line of a sur- vey in the morning, and in the afternoon to back in the compass line towards camp. In the evening the compass line can be trav- ersed, and if anything is found amiss it can be remedied the fol- lowing day. Every gate along the canal, the terminus of the canal, and the termini of each lateral, must be connected directly to the nearest available government corner by course and distance. All changes in width, and the points where such changes occur, should be noted. The United States has no control over the land which it has sold to settlers or others, and arrangements will have to be made with them individually for right of way ; but their claims, whether homestead or desert, must be ascertained and placed upon the maps which are sent to the General Land Office. Record should be made of the points where the canal enters and leaves natural washes. The land granted by the government is only for the purpose of the canal, and is not transferred in fee. The date of every day's work should be entered in the notes. When the location of the canal and the main laterals is finished it is usual to draw the map and write up the notes. These are filed in the nearest land office and sent from there to Washington, where they are examined, and if found complete and correct, are presented to the Secretary of the Interior for his approval. These maps and notes must be in duplicate. One copy is kept in Wash- ington and the other returned to the local land office, where it is kept on file and is open to inspection by the public. The land through which the canal runs is sold to settlers, re- serving the right of way, although no deduction is made in price, the benefits they are supposed to receive offsetting the loss of land. NOTES ON IRRIGATION CANALS, 205 The map should show the townships, ranges, sections and quarter- sections, and those sections through which the canal passes must show the smallest legal subdivisions, which are the forty-acre tracts. Entries made by settlers prior to the filing should also appear, and the portions of the public land through which the canal passes should be designated as vacant. These maps and notes should be filed with the register of the land office for the district in which such land is located, within twelve months after the location of ten miles of the canal if upon surveyed lands, and if upon unsurveyed lands within twelve months after the survey thereof by the United States. Forfeiture is declared if any section of the canal is not completed within five years after the location. All maps should be drawn upon a scale of not less than 2CX)0 feet to the inch. The connections of the termini of the main ditch and laterals with the public survey must be shown on the maps and described in the field notes and affidavits of the engineer. The line should be platted and its courses, distances and widths shown and the connections with the section corners and quarter- section corners given. The maps should be accompanied by the field notes of the sur- vey, which, like the maps, should be in duplicate, and in these notes and on the maps the variation of the magnetic from the true meridian should be stated. It is unnecessary for the maps to show the boundaries of the right of way, nor is it necessary to show the topography. How- ever, a slight amount of topography generally improves the appearance of the maps. If the courses on the maps are short, a neat arrangement is to number the compass stations only and to put the courses, distances and connections in the form of a table alongside of the drawing. In drawing maps for the government the top of the map is taken as being north, and inclined lines are lettered as follows (see page 206). When lettered in this manner inclined lines can be easily read without turning the map. Care must be taken not to make the maps appear crowded. They should be exceedingly plain and neatly drawn. Even the title should be plain. There should be absolute agreement between the two maps VOL. XV. — 15 2o6 THE QUARTERLY. and the two sets of notes; and to insure this they should be com pared at least twice. The maps must be drawn upon tracing cloth. Both the maps and notes should bear the certificate of the engi- neer and of the president of the company or the owner of the canal. These should be in the following form : Engineer's Certificate. John Doe being duly sworn, says that he is the chief engi- neer of [or is the person employed to survey the hne of route of the canal for] the canal company ; that the survey of the line of route of said canal from to , a distance of miles, was made by him [or under his direction] as chief engineer of the company [or as surveyor employed by the com- pany] and under its authority, commencing on the day of , 1 8 — , and ending on Ihe day of , i8 — , and that such survey accurately represents a proper grade line for the flow of water, and that such survey is accurately represented on the accompanying map and described in the accompanying notes; and that the head of the canal bears feet from the section corner to sections T. — N. R. — W. ; and that the end of the main ditch and beginning of the main lateral bears feet from the T. J4 section corner to sections that the terminus of the main lateral bears S., R. — E., and feet from the section corner to sections T. — S., R- — W., and that no lake or lake bed, stream or stream bed, is used for the said canal except as is shown on this map. Sworn and subscribed to before me this [seal.] John Doe, Chief Engineer, — day of , 1 8 — j Notary Public. NOTES ON IRRIGATION CANALS, 207 President's Certificate. I, Richard Roe, do hereby certify that I am the president of the canal company ; that ^ who subscribed the fore- going affidavit, is the chief engineer of [or was employed to make the survey by] the said company ; that the survey of the line of route of the company's canal, as accurately represented on the accompanying map and by the accompanying field notes, was made under authority of the company ; that the said line of route so surveyed and as represented on the said map and by the ac- companying field notes was adopted by the company by resolution of its board of directors on the day of , 18 — , as the defi- nite location of the canal described as follows (describe the same) from to — , a distance of miles ; and that no lake or lake bed, stream or stream bed, is used for the said canal except as is shown on this map; and that the map has been pre- pared to be filed for the approval of the Secretary of the Interior, in order that the company may obtain the benefits of the Act of Congress approved March 3d, 1 891, entitled *' An Act to repeal the timber culture laws and for other purposes." Richard Roe, PresicUnt of the Canal Company. Attest : • Secretary, . { SEAL OF 1 ( COMPANY. / If the survey is for an association of individuals or incorporated company the following papers are filed with the maps and notes : I. — Certificate of Organization, j^ ^ secretary [or president] of the Canal Company, do hereby certify that the organization of said company has been completed ; that the company is fully authorized to pro- ceed with the construction of the canal according to the existing laws of the State [or Territory] ; and that the copy of the articles 208 THE QUARTERLY, of incorporation [or association] of the company filed in the Department of the Interior is a true and correct copy of the same. In witness whereof I have hereunto set my name and the cor- porate seal of the company. [seal] , of the Canal Company. II. , being duly sworn, says, that he is the president of the Canal Company, and that the following is a true list of the officers of said company, with the full name and official de- signation of each, to wit : [Here insert the full name and official designation of each officer.] f SEAL OF > \ COMPANY* ) President of the Canal Company, Sworn and subscribed to, before me, this day of , i8 — . [seal.]. , Notary Public, III. A copy of the articles of incorporation, duly certified to by the proper officer of the company,' under its corporate seal. [No form can be given for this, as the forms in which articles of incorpora- tion are drawn up differ widely.^ IV. A copy of the State or Territorial laws under which the com- pany was organized (when organized under State or Territorial law), with the certificate of the Governor or Secretary of the State,, or Territory, that the same is the existing law. V. When the said law directs that the articles of the association, or other papers connected with the organization, be filed with any NOTES ON IRRIGATION CANALS, 209 State or Territorial officer, the certificate of such officer that the same have been filed according to law, with the date of filing thereof. Many of the above directions are taken from a small pamphlet issued by the General Land Office, entitled, " Regulations concern- ing Railroads claiming Right of Way over the Public Lands ; also, concerning Right of Way of Ditch or Canal Owners over the Pub- lic Lands and Reservations for the purpose of irrigation." This pamphlet may be had on application, and should be in the hands of every surveyor concerned in irrigation work. The engineering work of construction, with the exception of building the headworks, waste-gates, flumes, etc., is w^ry similar to railroad work. The ground is cross-sectioned, the amount of ex- cavation and embankment calculated and classified according to the specifications. Nearly all handbooks on railroad work treat of these matters, and special books and diagrams are published upon them, so it is unnecessary to dwell upon this part of the sub- ject very extensively. The cross-section of a canal may be partly in embankment, and partly in excavation, or, wholly in one or the other. The charac- ter of the ground and the grade of the canal determine this point. Embankments in light soil, and on heavy grades, are not advised, because of the liability of the water to erode its bed. To make a cross-section, half in embankment and half in excavation, lessens the cost of cohstruction. This is only possible on moderately steep hillsides. Before deciding to make a part of the canal wholly in excava- tion, the ground should be examined for rock, as this increases the expense of excavation from five to ten times over that of earth. The inner slope of a canal varies from 1 in i to i in 4, except in solid rock, where it is usually made about ^ in i. Rather more slope should be given than in railroad work. In embankments, shrinkage should be considered, and from 10 to 15 per cent, allowed. Flumes are built to carry the canal across streams, or along a steep hillside, where excavation would be very expensive. They are also rarely employed to prevent percolation, and, to a limited degree, evaporation. 2IO , THE QUARTERLY. The foundations of a flume must be secure ; and, if a stream is crossed, its flow must not be interfered with, or the foundations are liable to suffer. Leakage at the end of a flume must be guarded against. In order to diminish the cross-section, they are generally made deeper than the canal, and the sides have a slope nearer the perpendicular. The foundations may be rock, earth, piles, or trestles ; but no em- bankment should be allowed. If earth or rock, it should be care- fully levelled and mudsills laid. The superstructure should be securely braced and all the joints caulked — or else a tongue should be let in the planking. When the natural fall of the country through which the canal runs is considerable, and the canal must be carried through this land and water taken from it, falls or chutes are introduced. The effect of too heavy a grade is to cause the canal to erode its bed, and is due to excessive velocity. In the diversion line no harm is caused by this, but when the water must be diverted into laterals, it must not be too far below the ground surface. To effect this the velocity must be decreased, and this is done by concen- trating a large amount of the slope at a few points, and introducing falls or chutes. Falls are vertical, chutes inclined. If the canal is large, or the soil above the fall has little cohesion, the velocity of the canal immediately above the fall should be de- creased. To effect this a flash board weir may be introduced at the crest, or else the channel may be contracted. In the case of a fall the water impinges against a wooden- or masonry apron, or upon a water cushion, the canal for some distance (15 or 20 feet) above and below the fall being enclosed in a flume. When a chute is used a wooden flume is employed, and the cross-section of the stream is much diminished, and the discharge should be against some solid obstacle, which will throw the water back into a receptacle where it can flow over a flooring to the open canal. The water is drawn from the canal into main lateral ditches, which in turn distribute their water into still smaller laterals. These laterals should command the greatest area of land, and to that end should follow ridge lines closely, so as to distribute water on both sides of the ridge. Too little care is generally given to the location of the laterals. The bottom of the lateral should be higher than the bottom of NOTES ON IRRIGATION CANALS. 211 the canal in order to get the clearest water, and to discharge it from as great an elevation as possible. Laterals should be made large. More water will flow in a lateral of 8 feet cross-section than in two of 4 feet cross-section respectively, and the losses will be less. Waste ways must always be provided for the protection of the canal, and for the protection of weirs. Care should be taken to have them of sufficient size to carry off" all waste water in times of floods. They should always be constructed when leaving a natural wash and taking up an artificial channel. Outside of ordinary grading tools there are some special forms of scrapers, ditchers and graders used upon irrigating work. Some are worthy of mention, notably the Buck, and Fresno scrapers, the Benicia Ditcher, and the New Era Grader, all of which do good work, and move dirt in a surprisingly quick manner. After the canal and its laterals are completed, and the water is flowing, it becomes necessary to ascertain the number of second feet which are running, in order to dispose of it equitably and pro- portionately to the consumers. Water is either sold outright or rented. No method has yet been devised by which water can be measured and disposed of directly, that is by the numbers of second feet actually used. In India a certain proportion of the crop is generally taken. In the United States water is charged for according to the number of acres irrigated, and either rented out at a certain sum per annum or sold outright. To sell it directly some contrivance would have to be constructed whereby the exact amount entering the canal at any time could be ascer- tained, and this contrivance would have to be arranged so that it could not be tampered with. The second requirement is easily satisfied by using some kind of a lock, but the first is difficult of solution. The reason that the exact amount entering the canal cannot be determined is that the external head or pressure of the source of supply is continually changing, and the volume of water that passes through the headgate is never the same. The nearest solution to this question is to ascertain the amount entering the canal under various known heads, and under various depths; that is to say, to determine the amount under various depths of the source of supply in connection with the heights to which the headgate is hoisted. In the State of Colorado the State engineer does this work, and furnishes the water commissioners 212 THE QUARTERLY. and the canal owners with a table. The headgate is then raised to the required height and locked. This method only gives an approximate idea of the water passing through. The distribution of this water into the laterals, proportioning the proper amount to each of them, is another problem which is far from solution at the present time. Various water metres and dividing boxes have been tried, but* so far have met with but little success. In some of the States and Territories of the arid region it is necessary, before making the survey, to obtain a ^'waUr permit." . Application for this permit is made to the State engineer, giving the following information: The nature and extent of the proposed use. If for irrigation, the lands to be watered must be described. The place of diversion, the location and the character of the diverting works must be stated. Upon the approval and allowance of the application the appli- cant mu.st send a map to the State engineer within six months, showing the location and amount of the distributing works, the source of supply, and the legal subdivisions of the land upon which the water to be appropriated is applied. Information relat- ing to the laws regulating the water of a State can always be ob- tained from the Slate engineer. For the sake of simplicity this paper has been written, as if there was only one party in the field, while the fact of the matter is that there may be several, one running the main line, one running pre- liminary surveys to learn if different tracts of land can be brought under the canal, while others may be busied on the laterals and on construction. EVANSTO\, Wyomi NO, January 14, 1894, he above article was written the Department of the Inte- issued another pamphlet dated February 20, 1894, en- Legulations concerning Right of Way for Canals, Ditches ;rvoirs over the Public Lands and Reservations for the )f Irrigation," which gives more complete data for pro- han ever before. ition to the papers above mentioned, there is required 11 the company is operating in a Stale or Territory other in which it is incorporated. NOTES ON IRRIGATION CANALS. 213 I. The certificate of the proper officer of the State or Territory, that it has complied with the laws of that State or Territory, to the extent required to entitle the company to operate in such State or Territory. II. A copy of the company's title or right to appropriate the water needed for its canals certified as required by the State or Terri- torial laws. III. A copy of the State or Territorial laws governing irrigation, with the certificate of the Governor or Secretary that the same is the existing law. IV. A statement of the amount of water flowing in the stream sup- plying the canal at the point of diversion during the preceding year or years. For this purpose it is necessary to give the maxi- mum, minimum and average monthly flow in cubic feet per second and the average annual flow. All available data are required. The method of measurement or estimate by which these results have been obtained must be stated. Conditions are so varied that the department cannot be more explicit but must decide each tase on its individual showing. The field notes should state whether the middle or the side line of the canal was run. The stations and courses should be numbered. The kind and size of instrument used and its minimum reading on the horizontal circle should be noted. The method of running the grade line must be described. Whenever a public corner will be destroyed, marked monu- ments one on each side of the corner, must be set on the section lines. These monuments must comply with the requirements for witness corners of the Manual of Surveying Instructions (p. 31, ed. 1890), and must be placed far enough from the works so as not to be destroyed during construction. The line on which such monument is set, is determined by run- 214 THE QUARTERLY. ning a random line from the corner to be destroyed, to the first existing corner, setting a temporary mark on the random line at the distance of the proposed monument. If the random line strikes the corner run to, the monument will be established at the place marked. If not. the N. and S. or E. and W. distance to it is measured, the true course calculated, the correction for the tem- porary mark computed, and a permanent monument set in the proper place. The field notes for the surveys establishing the monuments must be in duplicate and separate from those of the canal, and certified to by the surveyor under oath. They must comply with the form prescribed in the Manual of Surveying In- structions. This last pamphlet gives a slightly different wording of the En- gineer's and President's certificates, but the subject-matter is pre- cisely the same. EvANSTON, Wyoming, April 7, 1894. SIMPLIFIED METHOD FOR OBTAINING THE ''AXIAL CROSS " OF ANY CRYSTAL FROM ANY PRO- JECTION OF THE ISOMETRIC AXES. By ALFRED J. MOSES. The substitution of direct measurement for the usual measure- ment, calculation and remeasurement employed in obtaining the axial projection of any crystal, diminishes the number of chances for error and is more rapid. The method herein described is ap- plicable to any projection of the isometric axes and is correct within the limits of a drawing. For illustration, the most frequently used clinographic* projec- * This projection is described in many text-books, notably C. F. Naumann, Lehrbuch der Krystallographicy 1 832 ; J. D. Dana, System of Mineralogy,, 3d. ed., p. 662, etc. The construction i^ as follows, Fig. I ; A horizontal line ss^ is bisected at O and trisected at t and Xf by perpendiculars. Distances s'e = % ss^ and sg = \ ss' are laid off as in- dicated. The point e determines the line cO, and A A'', the projection of the front horizontal axis is the portion of this line which is included between the perpendiculars at t and t'. The point g determines the radius Og, which is the length of half the projection of the vertical axis CC. For the projection of the third axis draw Af parallel to ss', draw fO, and from the intersection v draw vB, parallel to ss^ BB' is the de:>ired projection. OBTAINING ''AXIAL CROSS" OF CRYSTALS. 215 tion of the isometric axis is employed (Fig. i); and Figs. 3, 4, 5 and 6 are derived from it. t Fig. I. C \ ib -9 / is In Fig. 2 the diagonal scale measures thousandths, and a unit's length of this scale is the radius of the quadrant. The perpen- Fig . 2. 7 -^* ^^ ^ \* D \^ M %t A -# ou i no 8 \ T ifffQ J ^ a .4 j;i .^ .7 .^ .y 1, ■1 *P* :ti» H I I H i +*^ » EH dicular and horizontal lines from any degree of the quadrant are respectively the natural sine and cosine of the angle correspond- 2l6 THE QUARTERLY, ing to the degree multiplied by a unit's length on the diagonal scale. It is convenient in drawing to make the semi-axis OC (Fig. i) equal to a unit's length on the diagonal scale, though any desired ratio may be maintained by the use of proportionate dividers. In this article Figs, i, 3, 4, 5, 6 are one-third the scale of Fig. 2. In each of the following applications the isometric cross (Fig. i) is first assumed, and all measurements, whether axial lengths or sines and cosines of special angles, are measured on the scale or quadrant and laid off from the centre O on CC, and when needed the same proportionate parts of other lines are ob- tained by the application of the fact that " in any triangle a Ime parallel to the base divides the sides proportionately." Tetragonal Crystals. The recorded value of c \i measured on the diagonal scale and laid off on OC. Hexagonal Crystals. Fig. 3 gives the derivation of the axial cross of quartz (c = 1 .099) from the isometric axes. Fig. 3. Distances Oc = 1.099 and Om = 1.732* are measured on the diagonal scale and laid off on CC ; the former determines the ver- Bauerman's Systematic Mineralogy y 1889, p. 197. OBTAINING ''AXIAL CROSS" OF CRYSTALS, 217 tical axis, the latter is used in determining two lateral axes (BB' remaining as the third) as follows : Connect A and C. Draw mp parallel to AC. Connect p with B and B'. Bisect Op by a line I>arallel to BB' ; then ai and ag are extremities of the required axes. Orthorhombic Crystals. In Fig. 4 the derivation of the axial cross of barite is shown. The ratio for barite is a : b : c = 0.815 : i : 1.3 1 3. The distances 0.815 and 1.3 1 3 are measured on the diagonal scale and laid off Fig. 4. C » Fig. 5. . / ■ic ^ on CC as Os and Oc respectively. Oc is half the projection of the desired vertical axis. Os is equal to OC X 0.815 ; hence, if C and A are connected and sa drawn parallel to CA, Oa will equal OA X 0.815 ; that is, aa' is the projection of the desired brachy axis. MoNocLiNic Crystals. In Fig. 5, the derivation of the axial cross of pyroxene is shown. The constants for pyroxene are a : b : c = 1.092 : I. : 0.589 and /? = 74® 10'. The sine and cosine of 74° 10' are measured on the quadrant and laid off on CC as Om and 01 respectively. A and C are connected, mp drawn parallel to AC and the parallelogram pOlt completed to secure the point t and the line tO. The distances 1.092 and 0.589 are measured on the diagonal scale and laid off on CC as Ov and Oc respectively. C and t are connected and va is drawn parallel to C't; aa' is the projection 2l8 THE QUARTERLY. of the desired clino axis and Oc is half the projection of the de- sired vertical axis. Triclinic Crystals. In Fig. 6, the derivation of the axial cross of axinite is shown. The constants are a : b : c = 0.492 : i : 0.479, aAc = ^ = 9l° 52', b A c = « = 82° 54'. i-i A i-t ^(100) A (oio)^ = I ji° 39'. [a) To obtain the macro axis bb'. — The sine and cosine of 131° 39' (48° 21') are measured on the quadrant and laid off on CC as Os and Ok respectively. C is connected with A' and B, and the points e and d are secured by drawing se parallel to CB and kd parallel to CA' ; the point n results from the completion of the parallelogram dOen. Fig. 6. The sine and cosine of 82° 54' are measured on the quadrant and laid off on CC as Oy and Ox respectively. C is connected with n and yr drawn parallel to Cn ; the completion of the parallel- ogram rO xb secures the extremity b of the projection of the de- sired macro axis. {b) To obtain the brachy and vertical axes, — The steps are pre- cisely those for monoclinic crystals. The sine and cosine of 91® 52' (88*^ 8') are measured on the quadrant and laid off on CC as Om and Ol respectively. A and C are connected, mp drawn par- allel to AC, and the parallelogram pOlt completed to secure the point t and the h'ne tO. The distances 0.492 and 0.479 ^^^ measured on the diagonal scale and laid off on CC as Ov and Oc respectively. C and t are connected and va is drawn parallel to Ct; aa' is the projection of the desired brachy axis and Oc is half the projection of the desired vertical axis. AHneralogical Laboratory ^ Columbia College. A PERUVIAN SALT MINE. 219 A PERUVIAN SALT MINE. By ROBERT PEELE, Jr. On the west coast of Peru, about sixty miles north of the port of Callao, and a little south of Huacho, is situated a somewhat f remarkable deposit of salt. These " salinas," or salt fields, embrace portions of a nearly level tract bordering upon the ocean, — most of the area being practically at sea-level, some parts a little below. The field measures about four miles from north to south, with a width of from two to three miles. The workable deposit does not extend to the beach, for, close to the ocean is a narrow sandy tract, occu- pied by small shallow lagoons, containing a little salt and " caliche " (crude nitrate of soda). In the immediate vicinity of this salt plain the surface of the ground is covered by sand, with scattering ! meagre vegetation. The deposit itself is entirely superficial, varying in thickness from a few inches to at least twelve or fifteen feet. Excavations I fifteen feet deep have been made in several places without striking the bottom ; at other points the bottom is reached at from four to seven feet. The salt is not continuous over the whole field, but lies in irregular depressions, feathering out at the edges, where- the sand appears at the surface. To determine, however, whether the sand in a given place is the true bottom is not always easy, because in many parts which are not being worked the surface is covered with drifted sand. When this occurs glimpses of the white salt may be obtained by reason of an efflorescence which here and there raises the salt in flakes and lifts with it the sand covering. Below is the massive salt in layers of varying thickness, some nearly pure, some containing an admixture of sand and other foreign material. The *' caliche," or nitrate of soda, is usually found upon the surface in greater or less quantity, and when its propor- i ticn is large it is very troublesome, acting not only as an impurity, but eating away the salt in a manner comparable to the action of salt itself upon ice. In some places considerable areas of caliche occur, overlying the sand and black mud to a depth of eight or ten inches. The amount of salt existing in this deposit is very great, but it 220 THE QUARTERLY, would be difficult to estimate it until the development of the workings has been' carried much further. The process of extracting the salt in a marketable form is a peculiar though very simple one, resulting not only from the low and level nature of the deposit, but also from the climatic condi- tions which prevail on the Peruvian coast. For some purposes, such as the curing of hides, the natural salt, just as it is taken out, is of sufficiently good quality, but for the production of the purer grades the following method is adopted: At any convenient point the sand or other surface material is removed from the area to be worked, and the more or less impure salt is excavated to a depth of several feet, depending upon the thickness of the deposit. Generally a depth of two or three feet is sufficient, though deeper excavations are often made. These shallow excavations, called " potreros ** (literally in Spanish, '* pas- tures *'), are then flooded with water. It never rains on the Peru- vian coast, but in the months from June to September, — the colder or cloudy and misty portion of the year, — the level of the water in the lagoons bordering the seashore rises slightly, so that at any time during this season water may be admitted through small ditches to the potreros. This water soon becomes a satur- ated solution of salt in its passage from the lagoon, and by contact with the bottom and sides of the potrero, and subsequently by natural evaporation in the warm weather after September a rapid deposition takes place. This pure crystalline deposit of salt amounts to a layer of five inches, or thereabouts, per year over the whole area, and requires no further refining even for making table salt. In the month of October the water level in the lagoons begins to fall, and as evaporation advances the surface of the salt in the potreros becomes dry. This is the best time of the year for har- vesting the salt, for if it be left too long even the occasional gentle winds of the soft climate may carry some sand and dust upon the clean surface. Practically, however, this possible admixture of impurity is very slight, and it is customary to cut each potrero every two years. This is done similarly to the method of cutting ice by hand. The salt is divided into blocks from 1 8 to 20 inches square, and 8 to 10 inches thick. They are easily removed, because each time a fresh deposition takes place upon the old surface left by a previous cutting, there is very little adhesion between the A PERUVIAN SALT MINE, 221 layers, and after the blocks have been cut around to the depth of two layers a slight prying motion serves to separate them. The blocks are set upon edge in rows to drain and dry in the sun ; as roughly taken out b} hand their weight ranges from 1 30 to 1 50 pounds. It is intended to introduce channeling machines like those employed for ice, to cheapen the cost of labor, and to obtain more uniformity in the size of the blocks. Moreover, in doing the work with axes, a large amount of salt is converted into fines which must be sacked for shipment. The axes have narrow blades about 15 inches long, and with a cutting edge 4 to 4^ inches wide. In removing the surface for making new potreros, most of the excavated material is worthless, and is used only for making roads and embankments through the salt fields, upon which light port- able car tracks are laid to convey the salt to the main line of tram- road. Some of the purer salt, however, coming from the deeper portions of the excavation is sacked for shipment. Thus far but little regularity has been observed in opening the potreros, with a view to convenience of communication with the railroad, though improvements are in progress. The railroad is 30-inch gauge, and 6j^ miles long to a neighboring harbor, where a long wooden pier has been built for transferring the salt directly from the cars to vessels. A couple of small locomotives are used. The cars carry 5 tons each, and from 8 to 10 make up a train. Several grades of salt are recognized : 1. '^Sal Corriente." or the regular shipping product from the surface deposition in the two years rotation of working. It is pure and rather soft. 2. '*Sal de Corazon" (** heart salt"), the older salt, sometimes cut from the under layers, after the " sal corriente," or regular crop, has been removed. It is harder and may be mixed with a little foreign matter, due to having been worked over previously and to the drift sand. It is coarsely crystalline, often with a pinkish tinge. 3. "Sal de Espuma" (foam salt). This variety is of little im- portance, occurring only in small quantities just under the surface of the deposit when covered with sand, and is the result of efflor- escence of the original crystalline salt when long exposed to the air. It is pure, white, and exceedingly fine-grained. 4. A fourth grade is very coarsely crystalline, coming from the deeper portions of the deposit below the water level. VOL. XV. — 16 222 THE QUARTERLY, CATALLEL, METALLEL, SYNALLEL. By a. D. F. HAMLIN. The difficulty of finding simple and clear methods of express- ing elementary relations and propositions in mathematics, espe- cially in geometry and its derived sciences, is partly due to that very simplicity and laxity of grammatical construction which makes English so flexible and concise in all its ordinary uses. But it is also due to an actual poverty of vocabulary, which re- sults in the use of the same word or expression in several senses* and in the necessity of phrases or circumlocutions where precise terms are wanting. While in the natural sciences investigators never hesitate to fill up any gap in the resources of the language by the coinage out-of-hand of new words, our mathematicians have bravely struggled along with the imperfect outillage of old times. It is the object of this paper to break in upon this time-honored con- servatism by attempting to fill up this gap for a single but funda- mentally important series of geometrical relations. This deficiency is shared, it is true, by all other languages, and is consequently attributable rather to the mathematicians in general than to any peculiarity of our own tongue, but is none the less disastrous for that reason. It is that which exists in the treatment of the vari- ous kinds of parallelism, parallel transference or continuous equidistance between lines. Hitherto the nomenclature of mathe- matics seems to have recognized only two among them, which it has termed parallelism and concentricity, the former relating to right lines and the latter to curves. Two right lines are commonly defined as parallel when they lie in the same plane and are so placed that they will never meet, even though produced to infinity in either direction. This time-honored definition is imperfect be- cause it contravenes in direct terms the postulate of the higher mathematics that parallel lines do meet at infinity, and more espe- cially because it fails wholly to express the most obvious and prac- * It is hardly concise to say, •' The operation of graphically representing on an assumed plane the amount of protrusion of a projecting solid;" hut, on the other hand, it sounds like nonsense to express the same idea by saying, " The projection upon a plane of projection of the projection of a projection." This last form of statement is perfectly accurate and no doubt very brief, but it is absolutely unintelligible. CATALLEL, METALLEL, SYNALLEL. 223 tically useful fact about parallel lines, that they are at all points equidistant from each other. This fact of continuous equidis- tance it leaves to be inferred or deduced. Another definition of parallelism emphasizes the fact that the distance from any point in one right line to the nearest point in the other is constant ; a defini- tion which starts with the obvious fact of continuous equidistance, and allows the secondary fact to be deduced or inferred that the distance between the two lines measured /// any constant direction will be constant ; and the converse of this, that the measures of equidistance between parallel lines are themselves parallel in what- rver direction taken [aa^^ bb^, a^a^, byb2^ etc., Fig. i). The first of the above definitions has the merit of excluding from the outset all curved lines, and of thus differentiating abso- lutely between parallelism and concentricity. On the other hand, these two relations have this in common, that in concentric curves, as in parallel lines, the distance from any point in one curve to the nearest point in tlie other is constant. The second definition of parallelism given above, is on that account to be preferred, since it recognizes the common element in these kindred relations, while it differentiates between them by its expressed restriction to right lines. Thus the definition of concentricity may be made to correspond with that of parallelism as closely as do the relations which these words designate with each other, differing only in that which essen- tially differentiates those relations, namely, the rightness and cur- vature of the lines respectively. If we therefore define concen- tricity as that relation between curved lines lying in the same plane which exists when the distance from any point in either to the nearest point in the other is constant, it leaves us to deduce the corollary that these measures of equidistance are not mutually parallel, but normal to the curves, i.e.y towards or away from their common centres of curvature (Fig. 2j. Both these definitions call immediate attention to what is obvious and essential in the relations they define, and allow corresponding corollaries or deductions to be drawn regarding the direction in which the equidistance is measured. This is important in its bear- ing on certain other relations of continuous equidistance to which the text-books have as yet given no name, but which deserve both to be named and discussed. Their recognition in elementary mathematical text-books would, I am convinced, be a great gain to descriptive geometry and to the science of shades and shadows. 224 Tfi^ QUARTERLY, if not to geometrical discussion generallj'. These hitherto un- named relations are confined to curved lines, as it is obvious that CATALLEL, METALLEL, SYNALLEL. 225 right lines can in no way be equidistant throughout except when parallel and in the same plane. The words " parallel " and " concentric " have each, as we have seen, a precise and distinct meaning, and designate closely-allied relations of continuous equidistance between right lines and curves respectively. But there is no word to designate the relation be- tween a pair of equal and similar curves so situated that their dis- tance apart, measured in a given constant dir^ction^ is everywhere equal. In other words, if we displace or transfer all points of a given curved line a given distance in a given direction, they will form in their second position a curve equal and similar to the first, and equidistant from it at all points, if the distances be measured along the paths of transference (Fig. 3). The curves are obviously not concentric, for their measures of equidistance are not taken in directions normal to the curves, which, moreover, have not, like concentric curves, common centres of curvature, nor are the dis- tances constant between nearest points from one line to the other. The curves cannot be called parallel, for either definition of paral- lelism excludes curved lines. And it would be both undesirable and unscientific to extend the application of the word parallel to include such curves. Undesirable, because what our mathematical language needs is precision and restriction, not extension of terms ; unscientific, because the relation of parallelism between right lines is unique, and because the equidistance we are now endeavoring to find a name for is restricted in every case to measurement in one constant direction. In this respect, as well as by the fact of being confined to curves, it is more closely akin to concentricity, in which the direction of the equidistance is restricted. But here again there is a difference, for concentric equidistance is measured in constantly-changing directions, while in the curves we are consid- ering the direction of measurement is constant. Let us, for the present, call this relation that of parallel transference, and investi- gate a little more closely both its properties and its importance. The first of the two definitions of parallelism above given em- phasizes the conception of non-intersection, as the second does that of continuous equidistance. Concentric curves present to the eye a corresponding aspect of non-intersection ; they do not seem to approach to and recede from each other. They are, how- ever, in their very nature dissimilar curves. Having, throughout common centres of curvature (as 0, 0/ o'^ in Fig. 4), their radii 226 THE QUARTERLY. of curvature differ throughout by constant quantities, rendering the homologous portions obviously dissimilar. This becomes very noticeable in any series of concentric curves, as in Fig. 4, where the curve ^ ^z ^ ^ is as unlike as possible to b b b b. On the other hand, curves in parallel transference frequently do intersect ; they always appear to the eye to approach each other in certain portions and to recede in others, and they are, in the nature of the case, similar and equal curves (Figs. 3 and 5). All equal circles are mutually in this relation of parallel transference as Fig. 7 makes clear to the eye by the equal parallel measures aa, bb^ cc ; bb', dd\ €e\ etc. So far, there has been nothing said to limit the direction of the parallel displacement. But it is obvious that according as the trans- position is effected in the plane of the curve or otherwise, there will ensue radically different relations between the curves. In the first case they will lie in the same plane ; in the second they will be in parallel planes. In the first case the two curves may touch or intersect at one or more points ; in the second case they cannot intersect at all. In this second case the parallel paths of equal dis- placement^ or in other words the measures of the transference, make an angle with the planes of the curves and form right-line elements of a cylindrical surface, of which the curves are parallel sections or bases. It is therefore important to distinguish between these two sorts of parallel transference, and to find a name for each. This is especially necessary in view of the frequency and impor- tance of these two relations in descriptive geometry, and particu- larly in some of its special branches, such as isometric perspective and sciography. Equal and similar curves in parallel planes, like the bases of a cylinder, or the front and rear edges of a wheel, or of the intrados of an arch, though commonly spoken of as par- allel, are really curves in parallel transference in space, while their projections are curves in parallel displacement in a plane, and the lines of transference or equidistance in this plane are the projec- tions of the paths of transference, as da and bb in Fig. 6. But how cumbrous is all this designation by phrases instead of words, and how unreasonable in the case of such common and familiar phenomena, in so practical a science as descriptive geometry ! Curves in parallel transference have an aesthetic value in addi- tion to their mathematical importance. They form the basis of nearly all repetitive ornament and constitute one of the most essen- CATALLEL, METALLRL, SYNALLEL, 227 tial elements of architectural splendor. For the repetition of the same arch over a series of windows, or of any other architectural form in the plane of the wall is merely a case of curves " in par- allel transference in a plane," while a series of transverse arches re- peated across a long nave or arcade derives richness of effect from the repetition of the same curve in parallel planes, that is " in par- allel transference in space." Counterchange (which is so conspicu- ous a feature of Moorish ornament and of some other styles) and nearly all gothic diaper-work, when executed with curved lines, are instances of the decorative use of curves in parallel transference in a plane (Fig. 8). At the same time the frequency of concentric curves, both in architecture and in decoration, as in the mouldings of an archivolt, in Greek guilloches, and in Byzantine interlacing patterns, makes it only the more desirable to confer upon each one of these relations a definite and intelligible name.* These new names should be etymologically allied to the word parallel^ because of the kinship between parallelism and the rela- tions they are to designate. The only Greek prepositions avail- able in the compounding of the new words would seem to be xard, fiera and <Tov^ either one of which combines readily with akXr^kwv to form " catallel," f *' metallel " and " synallel." AWa means not only "according to," but also ''down upon," and therefore seems especially appropriate to the case of parallel transfers in space; that is, of equal curves in parallel planes, because of the suggested possibility of bringing any one of these curves down upon the other, i.e., of superposing them. M&rd^ on the other hand, with its suggestion of sequence and successiveness (''after," * There are many cases of lines in parallel transference which at first sight appear anything but equidistant throughout; seeming, indeed, to utterly belie the parallelism claimed for them. The fact is, that parallel transference preserves the semblance of parallelism only when, as in Fig. 9, a series of curves having a common tangent are displaced in a direction at right angles to that tangent (A^ A^). Displacement in any other direction results in alternate approaches and recessions, or even intersections, of the carves, as with A'B and \M^/ where the doited lines cc/ cU/^ etc., indicate the direction of the transfer. In B' QQ^^ we have an example of the simplest counterchange ; and Fig. 8 shows how even the most elaborate Moorish counterchanged quarry or diaper is produced by oblique transfer, as of the heavy line a^abc. Continuous equi- distance in these cases is not apparent though real : but it emphasizes the necessity of coining a name which shall not, by the use of the word '* parallel," call attention to a property seemingly lacking. f I owe to Prof. W. R. Ware the first suggestion of this word, although the use here made of it is slightly different from that to which he proposed to apply it. 228 THE QUARTERLY: either in time or place) is better adapted to express the idea of suc- cessive positions of the curve in a plane. Let us then call curves "in parallel transference in space" catallel curves, and their rela- tion to each other catailelism. In the same way curves " in parallel transference in a plane" should be meiallcl curves, and their mutual relation that of inctallelisnu We are now provided with a scientific, suggestive and appropriate term for each of the four most import- ant relations of continuous equidistance between lines; names ab- solutely restricted to definite cases, and impossible to confound one with another. The rails of a straight railroad track are par- allel ; when the track curves they are concentric ; the nearer and further edges of an arch-soffit, and the bases of a cylinder, are catallel; all equal circles in the same plane are metalUL The pro- jections of catallel curves on a plane are metallel curves. The shadow of a plane curve on a plane parallel to it is catallel to the curve, and the projections of the curve and of its shadow are metallel. If we call'the lines of equidistance (or *' paths of trans- fer") respectively " lines of catailelism " and " of metallelism/' we are able to state with perfect clearness and conciseness regarding the above curve and its shadow on a parallel plane, that ** the rays which cast the shadow are lines of catailelism between the curve and its shadow, and the projections of these rays are lines of metallelism between the projections of the curve and of its shadow." The whole discussion of the projection of shades and shadows, and, indeed, of many other problems of descriptive geometry is thus simplified and clarified, and many of the phenomena of solid geometry are rendered capable of concise and easy statement. The use of these terms is, therefore, herewith respectfully submitted to the consideration of mathematicians and teachers. There remain two forms of continuous equidistance which we have not yet discussed, but which are sufficiently interesting to deserve a word of comment, and possibly the coining of special designations also. The first of these is that of the parallel right sections of solids of revolution and of surfaces compounded from them. Such curves are not concentric nor metallel, because in different planes ; nor catallel, because they are unequal, except in the case of cylinders. But if their distances apart be measured along the generating or meridian elements of the surface, or along the chords of the intercepted arcs of these elements, they are found to be continuously equidistant. Moreover, the projections CATALLEL, METALLEL, SYNALLEL. 229 of these curves on a plane perpendicular to the axis of revolution are concentric curves, and they are thus brought into a certain kinship with those we have already discussed. Whether it is or is not worth while to apply to them the third of the names sug- gested above, and to call them *' synallel," we leave to the judgment of teachers and of writers of mathematical text- books. The name is not so rigorously descriptive as the other two, but is perhaps sufficiently so to serve the purposes of designation. It only remains to mention the case of curves, not plane figures themselves, which, when repeated by parallel transference, are uniformly equidistant in space though not' in parallel planes. There can be no objection to calling them catallel curves, since the rela- tion they sustain to each other is precisely the same as that of catallelism for each of their infinitesimal plane elements, and con- fusion cannot arise from such use of the term, because of the abso- lute distinction between plane curves and those which are not plane figures. The projections of such curves as these on a com- mon plane would be metallel curves, which further assimilates their relation to that of catallelism. And all these five species of con- tinuous equidistance between curves are brought into a common category by the fact that in all five cases the tangents to their homologous points are parallel ; or, in other words, that their homologous infinitesimal segments considered as right lines are in each case parallel. It would seem but reasonable to give each case its own name, and to expect that these new designations may help both to enrich and to simplify the discussions and investiga- tions alike of plane, solid and descriptive geometry. This confi- dent expectation the writer pleads as his excuse for presenting at such length the claims of the three new words which form the title of this paper. 230 THE QUARTERLY. DETAILS OF MODERN WATER-WORKS CONSTRUCTION.* By WOLCOTT C. FOSTER. Part II. — Cast-Iron Flanged-Pjpe and Special Castings; Valves. Flanged pipe is straight pipe with a flange or broad circular ring cast on either one or both ends (Fig. 21). If there is a flange on one end only, the other end may be either of a bell or a spigot form, and it is then known as flange-and-bell or flange-and-spigot Fig. 21. Flanged-Pipe and Flange and Spigot-Pipe. pipe. It may be obtained in any length up to 18 feet, but is usu- ally supplied in 12-foot lengths. The pipe is put in a lathe, and the flanges turned up or ** faced." Where the joints of the pipe are likely to be submitted to a ten- sile strain, for piping inside the pump-house, and wherever the piping is likely to require being taken apart once in a while, flanged- pipe and specials are used. There are other cases where flanged- pipe is required, but a little practice will soon enable one to decide when it is appropriate to use flanged pipe and specials. Unless otherwise specified, the pipe is shipped with the flanges blank or undrilled, leaving the bolt-holes to be drilled on the work. This, however, is expensive, and it is better to have the bolt-holes drilled at the pipe-works. When this is done, it is necessary to * Copyrighted, 1 894, by Wolcolt C. Foster. MODERN WATER WORKS CONSTRUCTION. ' 231 send the makers either a template or data, showing the location of the holes with relation to each other and to the axes of the pipe when it is other than straight pipe, the diameter of the bolt-hole circle (that is, to the centre of the holes — in fact, all measurements are made in reference to the centres) and the size of the holes re- quired, together with such other information as may be pertinent. Fig. 22 shows such a diagram for the bolt-holes in a flanged bend. Fig. 22. Data for drilling flanged bend. Holes drilled off centre ; bolt-holes ^-incli diameter ; bolt-circle xi inches radius; number of bolt-holes six. There is no universal standard of weights for flanged pipes, nor is there an universal standard as to flanges, bolt-holes, etc. Each foundry usually has its own standard, and, unless otherwise or- dered, sends that standard. Standards have been suggested from time to time, notably one by Mr. John E. Codman, of Philadel- phia, an abstract of whose paper read before the Engineers* Club, of Philadelphia, is given in Engineering Neivs of January 12, 1S89, p. 24. When flanged work is to be connected together or with valves, care should be taken to specify the outside diameter of the flanges ; otherwise, the chances are that when the work is bolted up, one flange will be found larger than the abutting flange, and either the work will be unsightly and unworkmanlike or the ex- pensive method of chipping and filing down the flange will have to be followed. In Table III. will be found some of the details in relation to the various sizes of flanged pipe turned out by one of the prominent foundries. Flanged special castings or flanged .specials are very similar to bell-and-spigot or ordinary specials, except that flanges replace either one or all of the bells or spigots. The general remarks made in the first paper on bell-and-spigot pipe and specials apply to flanged material. 232 THE QUARTERLY. Table III. — Weight and Dimensions of Medium Weight Flanged'Pipe, Diameter of Pipe. Length ,of Pipe. • I c H Medium Weight per Length including Flanges. « FlIncbs. • Diameter.* • e H Weight of Each. Diameter from Centre to Cen- tre ot Holes. Number of Bolts. • 3 1 en in. ft. in. lbs. in. in. lbs. in. in. 3 12 } 160 8J J 1052 6| 4 f 4 12 I's 240 9 1 11.82 71 4 1 6 12 H 378 12 «tV 21.03 10} 6 1 8 12 i 540 14 It 26.72 •H 6 } lO 12 tV 760 16 •i 30.73 14 8 1 12 12 i 1000 '8. 'i 38.33 16 8 I 14 12 f 1200 20 '} 43.23 i8i 10 } i6 12 ii 1500 23 «? ^64.51 20H 10 i i8 12 i 1800 25 »i 75.83 ii\ 12 \ 20 12 } 2050 28 •1 108.00 »5i 12 \ 24 12 J 2700 32 'i 130.47 29i 14 i 30 12 I 4000 40 «J 223.08 36J 20 1 I 36 12 'V» 5000 46 • 2 275.62 42f 24 I 40 12 •i 6000 50 4 313.81 46i 26 I 48 12 'i 8000 58 2i 378.20 1 S4i 30 >i The joints are made up by inserting a gasket of rubber packing, leather, sheet lead or copper between the abutting surfaces. The proper gasket to use will, of course, depend on circumstances, but as a rule sheet-lead is preferable. Flange-pipe is usually sold by the pound,, the same as special castings, and runs about the same in price for 12-foot lengths. When the lengths are other than 12 feet long, the price per pound is usually greater. , Valves. Water-works valves are made of cast-iron, with a few of their ' parts of a special composition similar to bronze. The ingredients * Compare with Table IV, MODERN WATER WORKS CONSTRUCTION. 233 and their amounts of this composition vary with the difTerent man- ufacturers, and are trade secrets. The valves are of the kind known as gate-valves, and may have either one or two gates. While there are some pretty well-known makes of the single-gate variety, those with double gates are more generally preferred and used. Of the latter kind, Figs. 23 to 25 show sections and outside views. Fic. J3. .^. ^ ffiL Purls of a Waler-Wojks Valve Fig. 23 shows the parts of an ordinary street-main valve of mod- erate size of the make known as the Eddy Valve. The following list gives the names of the parts, their uses and the material of which they are made : Case or body of the valve (cast-iron). 234 THE QUARTERLY. Cover or bonnet (cast-iron). Lower part of the stuffing-box for the stem (cast-iron). Stuffing-box follower (cast-iron). Stud-bolts and nuts for fastening the stuffing-box together and to the cover (wrought-iron). Bolts for listening the bonnet to the body (wrought-iron). Stem or screw by which the valve is operated (steel and com- position), Ball-nut or gate-carrier (composition), into which the stem works to raise or lower the gates. The hooks extending out- ward from the stem of this nut work in grooves in the edges of the gates, and keep them in place when the gates are raised off their seats. The rounded projections at the lower end are called the trunnions. Fin. 24, Fig, 25. Section of Eddy Valve, Persjiective View Eddy Valve. Gates or leaves of the valve. The body of the gate is of cast- iron, the facing-ring of composition. Stem-nut (cast-iron), placed on top of the stem to give a grip for the wrench or key used in opening and closing the valve, and which is kept in place by a nut. The stem-nut is usually two inches square. The seats (composition) are the surfaces against which the gates bear when the valve is closed. Fig, 24 shows a sectional view of one of these valves put to- gether, and Fig. 25 an outside view. MODERN WATER WORKS CONSTRUCTION. 235 After the seat rings and facing rings on the gates are put in place and turned up the gates are ground on their respective seats with emery to a perfect bearing. These valves are known as centre bearing, that is, the pres- sure to keep the gates against their seats is applied at the centre of the back of the gates. In some makes the mechanism causes the pressure to be exerted on the back of the gates at their outer edges, usually at two or more points of the circumference. Centre bearing valves are to be preferred, as they are more likely to dose tightly should some foreign matter lodge between one of the gates and its seat. Double gate valves may in general be divided into two classes : 1st. Those in which the seats are inclined to each other. 2d. Those in which the seats are parallel to each other. In the first class the gates take the form of a very long wedge when being closed, and consequently require but comparatively- little power to make them tight. In the second class the gales or leaves are pushed apart and held against the seats by wedges or similar contrivances when shut. Fig. 26 shows the interior working parts of a valve with parallel seats, as made by the Rensselaer Manufacturing Company. Flo. a6. Inlerior Parts Rensselaer Valve. The Eddy valve described above has inclined seats, is easily closed tight and opened, and has a minimum number of parts. Any valve for use in street mains should not leak with the pres- sure on either gate, while wholly relieved from pressure on the other gate. With some makes of valves it is necessary to place one of the gates, which is usually painted a distinctive color, facing the pres- sure. It is not desirable to use such valves, as in a well-designed 236 THE QUARTERLY. works the majority of the valves are likely to have the pressure on one face as often as on the other when closed. Valves are made to open by turning either to the right or left, as ordered, but unless otherwise specified usually open by turning to the left. The larger sizes of valves are geared with spur gearing when intended to stand upright, as shown in Fig. 27, and with bevel gearing when intended to lie on the side, as in Fig. 28. The size at which gearing is added depends upon the pressure and upon the depth that the pipe is laid in the ground. It is seldom that valves under 20 inches diameter have to be geared. With 40 to 50 pounds Fic, 27. Large Valve with Spur Gear to Stand. Upright, pressure it is usually necessary to gear valves 24 inches in diameter and over. As a rule, the larger sizes of valves in street mains have to be placed on their sides, otherwise they would extend above the jurfaceof the ground. Valves are made with a hub or bell on each end, with a spigot on each end, and with flange ends, with screw ends, or with any combination of these. The particular kind required should be specified, otherwise valves with a bell on each end will be sent. One or more by-passes or passages to carry the water around the gates when the valve is closed are placed on large gates. MODERN WATER WORKS CONSTRUCTION. 237 Large Bevel Geared Valve ivilh By-I'a.- I.. XV.— 17 238 THE QUARTERLY. ■These by-passes are closed by secondary valves. The object of the by-passes is to prevent excessive water hammer by a sudden or rapid stoppage of the entire flow and to partially relieve the pres- sure on the gates of the main valve when it is closed, so that it may be more easily opened (Fig. 29). When so desired, hand-wheels are placed on top of the stem in place of stem-nuts (Fig, 30). In ordinary valves the stem or spindle does not rise, i.e., as the gates are raised up the gate car- rier works up on the stem, while the stem always holds the same relative position to the case of the valve. Quick Opening or Sliding Slera and Lev^r Valve, Valve with Hand Wheel. For special uses, many other forms of valves have been designed, of which the following are among the more important: Rising stem-valves, in which the stem rises out of the case as the valve is opened. Sliding-stem and lever-valves, in which the gates are moved by a stem operated by a lever (Fig. 31). There is no screw-thread cut on the stem in this variety. They are usually marked S. S. & L. valves. Outside screw and yoke-valves (Fig. 32), known as O. S, & Y. Rack- and pinion-valves (Fig, 33). MODERN WATER WORKS CONSTRUCTION, 239 Fio, 37, FiR. 33, Hydraulic-lift valves (Fig. 34), in which the gates are moved by a piston operated by a hydraulic cylinder placed upon the valve. Ilydraulic-Lirc Valves, 240 THE QUARTERLY. Flu me- valves are intended to withstand only light pressures, and while outside they have much the appearance of the ordinary valves for street mains, they are much lighter in construction, and have but a single gate (Fig. 35). Sluice gates are of pec61iar construction, and are sometimes used on the inlets and outlets of reservoirs, especially for large sizes of pipe (Fig. 36). The principal outside dimensions of the standard Eddy valve, as made by the Eddy Valve Company, are given in Table IV. Table IV. — Dimefisions of Standard Eddy Valve in Inches. Sub. Screwed Valves. End to Knd of Sockets. Flangbe » Valves. Hub End Valves Diameter of* Standard Flange. Face to Face Flanges. End to End of Hubs. 2 4 6 8 ro 12 H 16 18 20 22 24 SO 36 5i 8 loj II '3i •4j 6 9 II 13 16 18 21 23 25 27 2^ 3" 38 45 51 71 9\ II 12 I3J 15 16} I6J 17} 18J 20 22} 25} 7i 12 I3i , '4i 15J 16 I7t 17J 18 18 20 22 25 30 When it is desirable to use the ordinary stationary spindle-valve and it is necessary to be able to tell the position of the gates, an indicator is attached to the valve. The kind of indicator varies with the conditions and the maker. Where the valve is exposed to view, a worm working into a gear may be attached to the stem of the valve as shown in Fig. 37, or an index-finger moving along * Compare with Table III. MODERN WATER WORKS CONSTRUCTION. 241 a scale and operated by a fine thread cut upon the exposed por- tion of the stem may be used. Valve Indicator, Fig. 38 shows another style of indicator. Where the valve is not exposed, a post indicator, as shown in Fig. 39, or some similar contrivance, may be resorted to. The standard nut placed on the valves is two inches square. The valve- wrenches should always be kept convenient and in their places, so that properly authorized persons can get them at a mo- ment's notice in a case of necessity. Care should be exercised in operating valves. When closed they should simply be brought •242 THE QUARTERLY. to a firm, even bearing, and should never be forced or jammed. If they will not close tightly with a moderate pressure on the wrench, something is wrong, and i{ forced,, injury is likely to re- sult. Either the stem will be strained, the threads stripped, some of the interior parts broken, or the faces of the gates or their seats damaged. As soon as the gates are off the seats the valves should work perfectly free and even* In newly-constructed systems, for- eign material, such as sticks, stones,, old shoes and miscellaneous articles are likely to be found in tJw pipes^ especially if the inspec- tion has not been quite as strict as it should be, and even with the best of inspection and care they sometimes get in. They will be found to gradually work aloi^ and find lodgement in either a valve or hydrant. If a valve will not close tight, the water should be shut off from the section on each side, and the valve taken apart by«removing the bonnet. It may then be cleaned out If the gates are raised up into the bonnet before removing^ it, all the inte- rior parts may be removed together. Care should be exercised not to tear or damage the gasket that will be fouixl between the case and bonnet. If this is injured and is not renewed the chances are greatly in favor of a leak. Table V. — Approximate Cost of Standard Make Double-Hub Water Works Valves^ Brass Mounted Iron Body. 8 lO 12 >4 i6 Diameter. Inches. Price.$9.00
15.50
22.50
30.00
40.00
60.00
75.00
li
Diameter.
Inches.
18
20
22
24
3^
Price.
120.00
160.00
200.00
350-0O
6co.oo
It will be noticed that in some of the foregoing cuts the valves
have screw ends. Screw-end valves are only used on wrought-iron
pipe, and these same styles of valves may be obtained with either
hub, spigot or flange ends for cast-iron pipe.
MODERN ^ WATER WORKS CONSTRUCTION. 243
The cost of valves varies from time to time and depends upon
the make, locality, condition of business and quantity. For esti-
mating purposes in the middle and eastern states for moderate
quantities the following prices, f. o. b. cars, may be used for stand-
ard makes. The actual contract price may be somewhut less, but
the estimate will be on the safe side and is not likely to be out
over a few per cent.
244 THE QUARTERLY.
CONTRIBUTIONS FROM T^^E ANALYTICAL LABORA-
TORIES OF THE SCHOOL OF MINES,
COLtJMBIA COLLEGE.
SCHEMES FOR QUALITATIVE ANALYSIS.
By J. S. C. WELLS, Ph.D. and A. R. CUSHMAN, Ph.D.
Chemical Reactions.
All chemical changes may be expressed by means of reactions
written in the form of an equation, e.g,:
BaCl, + Na^SO^ = BaSO^ + 2 NaCL
Now let 'us examine this equation and see what it is intended
to express by it. In the first place it is a kind of short hand for
chemical names ; instead of writing out the words barium chloride
we denote it much more easily by using the chemical symbol be-
longing to each element contained in the compound, thus in the
example given Ba stands for barium and CI for chlorine. Perhaps
you may ask why we write it BaClg and not simply BaCl. This
brings us to another important property of symbols, viz. : that
they not only represent the elements themselves but they also rep-
resent their atomic weights, as compared with the atom of hydro-
gen which is taken as the unit. Now in the example under dis-
cussion it has been found by quantitative analysis that it contains
137 parts by weight of barium and 71 parts of chlorine. The
weight of the barium atom has been found to be 137 times that
of the hydrogen atom, hence in this compound we have an amount
of barium equal to one atom. The chlorine atom has been
been found to be 35.5 times as heavy as that of hydrogen, hence
if BaCI, contains 71 parts of chlorine to one barium atom (137) it
must contain 71 -T-35.S (weight of i atom of chlorine) equals 2
atoms of chlorine.
This we denote by writing the figure 2 at the lower right hand
corner of the symbol of the element, hence we see that BaCI,
means in the first place, the chemical compound barium chloride;
SCHEMES FOR QUALITATIVE ANALYSIS. 245
second, that it represents definite weights of the constituent ele-
ments, and also the number of atoms of each element in the mole-
cule.
When a number is written before the symbol representing a
molecule, as 2NaCl, it means ,two molecules.
If we should perform the chemical operation expressed by
the equation given we would find that 208 (Ba 137 + CI271) parts
by weight of barium chloride and 142 (Nag 46 + S 32 + O4 64)
parts of sodium sulphate would produce 233 (Ba 137 + S 32 +
O4 64) parts of barium sulphatft and 117 (2(Na 23 + CI 35.5) )
parts of sodium chloride.
It should be remembered that in all equations representing
chemical change, that the number of atoms on one side of the
equation must be exactly equal to those on the other ; nothing can
be gained or lost.
Having gained some idea as to what an equation means let
us see if they differ from each other in any important respects.
In the equation cited, it is evident that we have a simple inter-
change of the elements contained in the two substances used, the
barium replacing the sodium and the sodium the barium ; such a
transposition is called metathesis and to this class of equations be-
long a very large number of chemical reactions.
It is a general r^ule,that if we mix two solutions, capable of form-
ing by exchange or transposition a compound insoluble in the mix-
ture, such insoluble compound will be produced and precipitated.
In the case just given, although BaCla and NagSO^are both soluble
in water, yet when we mix them, BaS04 is precipitated, because it
is insoluble in water.
Other forms of chemical change are those of combination or
synthesis as :
H2-hCl2=2HCl '
2C + O2 = 2CO.
tho«?e of dissociation or analysis as :
CaCOj (on ignition) = CaO + COj
2AUCI3 " = 2Au + 3CI2
and those of oxidation and reduction, the latter two representing a
very important series of reactions. Oxidation, strictly speaking.
246 THE QUARTERLY.
\YOuld mean an increase in the quantity of oxj'gen contained in a
body, but the term is often used when oxygen takes no part in the
work, as when FeClj is changed to FejCl^ by means of chlorine.
2FeCla + CI2 = FcjClg.
Although oxygen does not enter into the reaction we say the FeClj
has been oxidized, meaning that it has been changed from a salt
corresponding to FeO to one corresponding to FegO,.
As an example of an oxidation equation let us take the one
showing the oxidation of FeS04 to FejCSOJj by KjMnjOg and
H2SO, :
SFeglSO^)^ + KjMnA + SHjjSO, =
SFe^tSOJa + KjSO, + 2MnS0, + SH^O.
In order to write such an equation as this, it is necessary to
know first, how much oxygen is needed to change the body from
the lower oxide to the higher ; second, how much oxygen we can
get from each molecule of our oxidizing agent and what are the
by-products formed by the reduction or decomposition of the lat-
ter ; also what are the other products if any, that are formed by the
chemical changes going on. In order to determine the amount of
oxygen necessary, we will first examine the composition of the
body to be. oxidized, FeSO^.
Ferrous sulphate probably contains two atoms of iron in the
molecule, as shown in the following graphic formulae :
Fe = O ,, Fe = SO4 T.
Ij Ferrous n * Ferrous
Fe = O °^*^^ Fe = SO, Sulphate.
The composition of ferric sulphate, the product of the oxidation,
is shown by the foll6wing formulae :
/ Fe = O / Fe = SO,
0<^ r Ferric SO/ | Ferric
^ Fe = O oxide. ^ Fe = SO, sulphate.
On comparing the formula for ferrous oxide with that for ferric
oxide, we see that in the reaction, every molecule of the former has
taken up one more atom of oxygen, in order to become ferric ox-
ide, or in other words, the ferric oxide contains one more atom of
oxygen in the molecule than does the ferrous, hence, every atom
SCHEMES FOR QUALITATIVE ANAL\ SIS. - 247
of oxygen yielded by the oxidizing agent, will oxidize one molecule
of ferrous oxide (FejOj), to ferric oxide (FejOs).
Next let us see in what way the permanganate acts with the sul-
phuric acid. It has been found that it is decomposed or reduced,
when in presence of an oxidizable substance, as shown in the fol-
lowing equation :
KjjMnPg + 3HjS0,= 2MnS04 + KjSO^ + 5O + 3H2O.
From this we see that every molecule of the KjMnjOg will yield
five atoms of oxygen, free to enter into combination with the iron
and we have already determined that each molecule of ferrous
oxide (FejO^) requires one atom of oxygen to change it to ferric
oxide (FcjO,) ; hence, five atoms of oxygen will oxidize five mole-
cules of the Fe^Oj to FejO,. Next, how much H2SO4 will be
needed besides that already contained in the ferrous sulphate.
Ferric oxide when it combines with H2SO4 does so in the follow-
ing manner :
FeA + sHj^O^ = Fe2(SO,)3 + 3H2O.
Hence it is evident that for each molecule of FegOg we shall need
three of H^SO^, but as there are already two molecules present
in the ferrous sulphate, we shall actually need but one more for
every molecule of iron oxidized, and for five, the amount oxidizecj
by one molecule of KgMngOg, five H2SO4 will be required, making
eight in all, with the three needed for combination with the po-
tassium and manganese of the permanganate.
We have now determined the quantities of each reagent taking
part in the reaction and also the quantities of the products.
We will now take another reaction, in which at first sight, the
action of the oxidizing agent is not so plain. If we heat chromic
hydroxide with a solution of sodium carbonate and bromine, the
chromium will be oxidized to chromic acid, although of course,
the bromine itself contains no oxygen. Let us first write down
the substances taking part in the reaction and the products formed.
Cr2(OH)6 + NagCOa + Br = 2Na2Cr04 + NaBr + COg + H2O.
The substance to be oxidized Cr2(0H)g, consists of Cr203 +
3H2O ; the result of the oxidation, NajCrO^, consists of NajO +
CrOj." As the molecule of Cr2(OH)Q contains two atoms of chro-
248 THE QUARTERLY,
mium, we must, if all the chromium is oxidized, produce two mole-
cules of Na2Cr04.
In NajCrOi, the CrO, is the acid anhydride and it has formed the
salt by acting on NajCOg as follows :
NajCOj + CrOj = Na^CrO, + CO,.
We see, therefore, that the product of the oxidation is really
CrOj and that the NajCrO^ results from the action of the CrO, on
NajCOj. Now if we start with a molecule of Qxjd^ and obtain
as a result of the reaction two molecules of CrOs, it is evident as
shown by the following formulae :
crA = { f^: 2Cro, = { jg;;-
that the CrjOj has taken up three more atoms of oxygen in the
change to 2Cr03, hence for every molecule of CrjO, oxidized, we
must have three more atoms of oxygen. How does the bromine
furnish it ? It has been found that Br in alkaline solution, acts as
follows, when oxidizable matter is present :
3Na,C03 + 6Br = 6NaBr + 3CO2 + 3O.
6 parts of bromine and 3 of sodium carbonate will thus give us
sufficient oxygen for the oxidation of one molecule of Cr2(0H)g to
2Cr03.
The 2Cr03 formed then combines with more of the sodium car-
bonate to form sodium chromate as shown above.
We will then need, besides the three molecules of carbonate that
react with the bromine, two more to combine with the 2Cr03,
making five in all, hence the complete equation will be :
Cr2(OH)6 + sNa^COj + 6Br =
2Na2Cr04 + 6NaBr + 5CO2 + 3H,0.
An equation representing oxidation, generally represents reduc-
tion as well ; reduction meaning just the reverse of oxidation. In
the case just considered of the oxidation of ferrous salts by per-
manganate, the latter is reduced, that is, loses oxygen and becomes
manganous sulphate, while the iron salt is oxidized. Sulphurous
acid is a strong reducing agent, owing to the facility with which
SCHEMES FOR QUALITATIVE ANALYSIS. 249
it takes up oxygen and becomes sulphuric acid. This is shown
in its action on ferric salts, thus :
Fe2(SO^ + SO2 + 2H2O = 2FeSO, + 2H2SO,.
Stannous chloride (SnClj), is another active reducing agent ;
when added in excess to a solution of HgClj, it reduces the latter to
metallic mercury; at the same time it is oxidized to SnCl4, thus :
2HgCl2 + 2SnCl2 = 2Hg + 2SnCl4.
Many more examples showing oxidation and reduction might
be given, but sufficient have been shown to serve as types of all.
SCHEMES FOR ANALYSES.
Preliminary Tests.
Before beginning the regular analysis of any substance, a pre-
liminary examination with the blowpipe should be made. A
number of metals are very quickly determined in this way, and
the knowledge as to whether they are present or not often simpli-
fies the analysis very materially. For the methods to be followed
in making these tests, consult The School of Mines Quarterly,
November, 1892, page 25; or Fresenius, § 175; also Prescott,
Table I.
Solution.
If the material given for analysis is not already in solution, the
next step, after making the preliminary examination, is to dissolve
it. Two cases are to be considered, viz. :
1°. The substance is neither a metal nor an alloy.
2°. The substance is a metal or alloy.
Substances of the 1° class are to be treated as follows :
A. — Boil some of the finely-pulverized substance with water.
a. All dissolves.
Test solution according to Scheme No. I.
b, A residue refnains.
Filter, and evaporate to dryness a few drops of the filtrate in a
platinum capsule, and see if any appreciable residue remains ; if
so, test filtrate according to Scheme No. i.
250 THE QUARTERLY.
B. Residue insoluble in water.
Boil a part of this residue with strong HCl (note if any gases
are evolved), then dilute with water (not enough to precipitate bis-
muth or antimony as basic salts).
a. All dissolves.
Evaporate solution to expel excess of acid, and then test accord-
ing to Scheme No. i, Filtrate i.
If silica has been shown by the blowpipe, in the preliminary
tests, evaporate the solution to complete dryness, add a little HCl,
boil, dilute with a little water, and filter from the separated SiOj.
b. A residue remains.
Treat a small portion of this residue with boiling water, filter,
and test filtrate for lead with H2SO4 ; to the residue left after treat-
ment with water add NH^OH ; filter, and test filtrate for silver with
HNO3.
The presence of mercurous salts will be indicated by the resi-
due turning black after the addition of ammonia.
The remainder of residue b save for treatment with residue C, b.
C. Take another part of the residue insoluble in water (5), and
boil with strong HNOj, then dilute with water (not sufficient to
precipitate bismuth or antimony).
a. All dissolves.
Evaporate solution nearly to dryness (if silica is present, evap-
orate to complete dryness, as in 5, a, using HNO3 to dissolve dry
residue instead of HCl), to expel excess of acid ; then dilute with
water, adding a few drops of HNO^, if the water causes any
turbidity.
Test solution according to Scheme i.
b. A residue remains.
Add it to residue B^ b^ and boil with aqua-regia ; dilute and
filter, and test filtrate by evaporating a drop on porcelain capsule,
to see if anything has dissolved ; if so, evaporate excess of acid
and add to solution By a.
Residue insoluble in aqua-regia. Treat according to D.
D. Residue insoluble in aqua-regia.
This residue may contain : AgCl, PbSO^, BaSOi, SrSO^, CaSOi,
SiOj and silicates, AljOj, CrjOj, CaF^, C, S, SnOj.
a. Test a small portion on charcoal or plaster, for Ag and Pb.
If found, proceed according to r; if not, proceed according to
Residue 2°.
SCHEMES FOR QUALITATIVE ANALYSIS. 251
b. Test another small portion in a glass tube closed at one end,
for S.
c. Silver and lead salts are present.
Take some of the residue, and heat with a concentrated solution
of NH4A; filter, and repeat treatment until lead salts are all
removed.
FiLT. I®.
1°.
whito ppt.
Pb804.
20.
if necessary, and
of BaCl2, wliite
ppt. = BaSOi =
H2SO4.
Residue \^.
Warm residne with KCy (if S is present, di-
gest in the cold), filter, and repeat the treat-
ment until Ag salts are all removed.
FiLT. 20.
(NH4)2 S, brown ppt.
= AgaS — . Dissolve
Ag2S in hot HNO3, di-
lute, filter, and to
Ag.
Residue 2<*.
If S is present, heat res-
idue in porceUiin dish un-
til the 8 has completely
volatilized: tiien mix the
residue with NaKCOa and
a little NaNOs, and fuse in
a platinum crucible; dis-
solve the fusion in boiling
water, filter and wash.
Residue 3^
BaCOs, SrCOs, CaCOa, (SiOj, _ AhOn,
CraOa, SnOa)? Treat with HA; heat and
filter.
FlLT. 40.
BaA?, SrA2,
CaA2. Test in
the usual way.
Residue 4''.
SiOi. SnOj, etc. Place
in test-tube with Zn
and strong HCl and a
few small pieces of pla-
tinum — SnOi if pres-
ent, will be reduced t<>
Sn. (See S. 0/ M. Quart.,
July, IbOl. p. 296). Dis-
solve in HCl, and test
with HgClj.
Filtrate. 3P.
NaaSiOs, NaF, NaaC'i-O*. NaiAlaO*, NaaSO*,
NajSnOs. (?) Make slightly acid with HCl,
and evaporate to dryness ; if Cr is present,
a('<d a little alcohol ; (do not heat much
above 100° C.) Add HCl to the dry res-
idue, boil, dilute and filter.
Ppt. 5.0
Si02, SnOi (?).
Prove iSiOa by
salt of phospho-
reduction witli
Zn
Filtrate 5.^
NaF, Al-iCU, CraClc,
NajSOi, SnCU (?j. Pass
H2S gas into tlic solut'n
and filter from any ppt.
Ppt. 0.
SnSs, S.
Filt. 6.
NaF, AI2CI6,
CrsCle -f
Na2S04.
add NH4OH to faint alkaline reaction and filter.
Ppt. 7^.
Al2.(OH)«and
CrstOHs. Test
in the usual way.
Filtrate T^.— (Divide in two parts).
1.
Acidify with HCl
white ppt. =
Add CaCl2 and let stand for some time ; filter,
and test ppt. for Fl. by etching test.
A better way to test for Fl. would be to take
BaS()4— H2S0 4. some of residue No. 2 and test that directly, ei-
ther by etching test, or by passing SiF4 into water.
252
IIIE QUARIERLY.
Mttals or Alloys.
Case 2^. The substance is a metal or an alloy. Boil with strong
HNO3, 3nd evaporate nearly to dryness ; add a few drops of HNO3,
dilute with water, boil and filter.
Residue l^'.
Residue is white and non-metallic. Boil with strong eolation
of H2C4U4OB: if any residue remains filter and wash.
Filtrate V.
Test according
to Scheme No. 1.
FiLTKATK 2**.
drops of HCl, and
pass in II sS, an
orange ppt. =
Sb-^Ss.
. . Residue 2*'.
• Place in a platinum capsule with a piece of zinc and a little
strong HCI. The Il^SnOs will be reduced to metallic tin. Re-
move the zinc, dissolve the tin in HCl, and test solution with
IlgCla ; a white or gray ppt. proves Sn. Gold and platinum, if
present, will be left undissolved by the HCl, and should be tested
ibr by dissolving in aqua regia, dividing solution into two parts,
and testing for gold with FeSOi, and for platinum with KCl.
A
UO'
•la:
II tl
iiif
° M
:. 1, w
hov
lilt
It
«S5
Aa
II on
nio«
. I
^
Filtrate 15.
° Method for An.
Tja, + AjrN(>i + HNO3.
.. 11, wariu, shake and filter.
♦'« J.: ApCI. Reject.
lAsOa. Saturate with HiS.
hows AsiSa, and proves As.
2° Method for An. (20.)
HgAsO, 4- AgNOs -f- H>J03.
Add a few drops of AkNO,. and tlien
NaC2H»02. Yellow ppt. shows AcjmAsOs,
(20) and proves As.
iHsa
lUti
st-tl
vsl
Tti
)W
SCHEMES FOR QUALITATIVE ANALYSIS. 253
\.
**HgS forms, with SnSj, after treatment with (NHJjSx of the
mixed sulphides, a compound readily soluble in water. To avoid
this the following modification of the scheme should be used :
Digest the precipitate of mixed sulphides with (NHJjSx ; warm,
and filter through a dry filter. Wash the residue with a lo per
cent, solution of NH4NO3 instead of using water.
Besidue a.
(HgS, Sn3a), PbS, CuS, CdS, BiiSg.
Beiuove from the filter, and heat gently
with dil. HNOs. Filter and wash.
Residue B.
HgS + HaSnOs.
Treat with aqua-regia in a porcelain
dish. Boil, to expel excess of aeid.
Filter.
Residue C.
HaSnOj.
Test on charcoal, by cobalt nitrate, in
the O. F. of the blow-pipe. A bluish-
green mass shows Sn.
Filtrate A.
Sulpho-salts of the 6° group.
Proceed according to the usual scheme
of separation.
I
Filtbate B.
Fb(NOs)s + Cu(N03)s + Cd(N03:2 -f-
Bi(N0s)3.
Proceed according to the usual scheme.
Filtrate C.
Hg CI2.
Add a few drops of SnCls, and heat, a
white ppt. turning dark, shows Hg2Cl3
and proves Hg.
VOL. XV.— 19
254
THE QUARTERLY.
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$s bO M .S s s C 5z; 5 bc 3 + a c8 a en 94 W + 1 4- < 5 Jz; W es ??; Jz; ^ -< c; N K ^ s SCHEMES FOR QUALITATIVE ANALYSIS. 255 o o s o ill 00 s II c5 5e; 9 o 1 a p? (N It W Hi o a A ^ 1 S 2 0^ T5 T^ 5 5 C4 w o ^ ^ [3 g SJI si •-4 « ^,.^ ^J = O •!> e e S5 8 1 r« M ' w "-"- ^'^s [III u . n ^1 s 9 J 5 J 5 5J H •i 5 .2 1 i o o g S &« o L S 5J5 o GO o 9 Q J ^ en o o o QQ o 9 O .a slsj 1 Q •'' s o o ►. 73 ^\ a O d I5J ^ •5 5 "^ s •a ^ ^ .^ o o be O a. 08 d? =§1 s s^ s "^ r £3 •"* 2 CO 0^ n ^ s • • 'A s ' OQ • V4 -^ n h5 <5 o in ^ ^ ^1 5)5 w o « J o OD a r^ oa £f S ll :?}l s^ll :s o o QQ .a a) O bO w bo W 15J 5 9* 1 o i-s ft. J 5 2 w o .0 K O f bo a O bc J bc I w la J ^ o . ,a ;::^ : ^ ►» • « '^— : >.i •* • .0 Pi J Oh J ^ » ^ ;« o a 55 9 o % "< s t o ^ ^ a bo I » CO ,i4 o OS i ^ 111 S" 111 O «> 9 CO H + CO c5 "bo W <5 5z; bo 6' O n o d ^ u « O bO o 2 ho 11 ►» O i^ a + + P. co o + CO a O O o o bo gji Jz; o bo S o H o o bo o ^ - S bo W J ^ ii S 3 O u I bO ,9 ^1 „ ^ « I ^ ^ •« ® O 6i5 u I y bo j bO <5 M OS 5z; M O 64 .9 o bo -< ' GO bo (5 <5 5" 5^ £^ .. M W « W M •* X3 .a « 2s6 THE QUARTERLY. *he Absenci F slight excos TE 22. in cold dill U a little i vitU NaiCl levi cork In 0H)«4-A dilate the water. Scheme III. — The Separation of Al, Cr, Ti, Co, Ni, Zn, Mn, Fe by KOH and Bromine. In the method commonly used for the separation of the above metals by means of potassium or sodium hydrate, the presence of zinc or chromium in the same solution very greatly compli- cates the analysis, owing to the fact that these substances precipi- tate each other in alkaline solution. The following scheme avoids t^^Vcfi this difficulty and is rapid and accurate. t«d. Fii To the solution of the metals, add NH^Cl in moderate quantity, then NH4OH until solution becomes slightly alkaline, and finally (NH J2S until solution smells distinctly of that reagent ; stir well and heat gently for some time,, filter and wash the precipitate. »».. an ^he Absence of Phospk ' »^— ■— ^—^— — — i^ FiLTKATB 3. I slight excess ; warm and rE 22. in cold dilate HCl (sp. gr« MnCI iM a little couc. HNOsi, an^ vitb Na^COs, and poar inM 4' 11 cork loosely and shall Ppt. 26. OH)« + Ah(0H)6 + crt(a: dilute the solotiou and adi water, Ppt. Fe,(OH)«+Al2(03 . and fose in a platinum t of KCKJs : digest the ful ted. Filter and wash. -r'Tw cm SCHEMES FOR QUALITATIVE ANALYSIS. 257 ^ Filtrate l**. Contains the alkalies and alkaline earths. Precipitate 1**. Treat with cold, dilate HCl (sp. gr. 1.02) in mode- rate excess *, filter and wash tbe residue thoroughly. Residue. (GoS and NiS). Test in borax bead, Bhie bead = Co. Brown bead ^ Ni. If Co is found to be present, treat the residue of sulphides as follows : Place in a small evaporating dish, add aqua-regia and boil, evaporating nearly to dryness; dilute with a little water; filter, if necessary ; nearly neutralize the solution with KOH ; add KCy in mod- erate excess — make strongly alkaline with KOH, and add Br, and warm, tak- ing care to keep the solution strongly alkaline. Filter, and wash precipitate tbor- ougbly with boiling water. Filtrate 2*^. Evaporate nearly to dryness, to expel UtS and the excess of UCl ; dilute with a little water; filter, if necessary, from any separated sulphur* ; add strong so- lution of KOH in considerable excess, and then a few drops of bromine, (it is better to use pore bromine rather than bromine- water) ; heat gently for a few minutes, filter, and wash precipitate with boiling water. Filtrate. Cobalt may be deter- mined in this solution, if necessary, by acidifying with HNOa, and then add- ing (Hg)2(N03)a; filter, and ignite the precipitate, and test residue in borax bead ; blue = Co. Ppt. (Nl9(0H)e. Black. Test in borax bead - brown bead = Ni. Ppt. 3. Test a portion in NazCOs ; bead in oxidizing flame, green bead = Mn. Dissolve some of the precipitate in HCl ; test a portion of this with NH4CyS for iron. Red color = Fe** ; test re- mainder of solution with Zn or Sn — violet color = Ti. Filtrate 3°. Divide solution into three parts. lo. Oo Pass HsS gas into the solution (not to satura- ation) — a white precipi- tate, insoluble in KOH .= ZnS. Acidify with HCl, then make very faintlv alka- line with NH4OH — a white flocculent precipi- tate = Ala(0Hj6. 3« Acidify with acetic acid and add a few drops of plumbic acetate — yellow precipitate = PbCrO* = Cr. • If the color of the solution at this point does not Indicate the presence of chromium, the treatment with bromine may be omitted, but in ihis case, Iron (if present) must be oxi- dized by boiling the solution with a little IINO3 before the addition of the KOH. A solution, containing one part of chromium in ten thousand of water, shows a distinct bluish-green color, consequently a colorless solution could not contain more than a trace of that metal. 25S THE QUARTERLY. > f^ -f- CO %nin!di99Jd: » 52? •«»«ni!a St to oogg e^droaj^ BO u '^ a » fi " *• ^ .. /^ C •^m _-i ^ •• M ^.^ \J NSJ^do35«5z;S5 'uoi;ii[og O a + 525 fS r-m "^ ••••'* •-• •-• v-< a* n **^ ^4 <oE-^c252;MScs*SacO«J45z; o + -^^- S U eS ^- i4*»> c"" Sfc2 a^»— ^. o '%^d 1 > til < •cao «n.?i!j / — ' — * 6^i4 ^MOS W o + CO •■ e« •niog OS *■ _ _ _' o L. o 6 d I II 6 + S OS + P14 w + ft a 01 U « CI4 ©• Op=0 o + Pu '%^d 01 S'^dj H • j» I. « w c w 9, € ^ tEtsJsS -< PM ^nUPh , '^ —'.--' V .^ f •i>d<i •uoianiog • * , ' QdJ * « ' >5i <5 w t5 ta c5 {Zi p4 + 4- ^ -4- 9 9-r ^ UMtiii^ <{NtiJ><Jtttt I ^wtswtija %. mmm^ > > — — .^ ' uoi!»niog •ooijniog • • * <5 5 a t3 » + + + 1-H 01 CO .43 ■AS •«3 t* h U a eS OS Ph PLH Ph o CO O 06t§ '€ oawin*! <5a05 9* et f* >m^ > , ' . tt O u « w ^ Cis © a fl •piB9a •g a»«n5J O o 1 PQ 26o THE QUARTERLY. Scheme IV. — " Phosphate Separation" The Separation and Detection of Al, Cr, Fe, Co, Ni, Mn, Zn, Ba, Ca, Sr and Mg, in the Presence of Phosphorjc, Arsenic, Oxalic, Boric, Silicic, Hydro- fluoric, Acetic or Tartaric Acids AND Organic Matier. If a solution containing the above-mentioned acids and bases is made alkaline with ammonium hydrate, the following is likely to occur : H,PO, ppts. Al Cr Fe(ic) Co Ni Mn Zn Ba Sr Ca Mg HjBOj (c k^ i( it <( u t( «( « (i « H,SiO, (< « (< « n (4 i« (f {( (( u HF t( {( {» «( »< «( t( (1 <( tf t< H.CA chiefly t( (( t( <i HjAsO^ Fe(ic) and Mg HjC^II^O^ prevents precipitation of Al, Cr, Fe. HCjHjOj if solution is boiling and neutral, throws down Al, Cr and Fe as basic acetates. To test for the presence of these acids three small portions of the main solution are taken, as follows : Part I. Add HNOj and *(NHj6Mo7024 a yellow cryst ppt. in- dicates phosphates. Part 11. Add HjC^H^Og and NH^OH in excess ; a gelatinous ppt. indicates phosphates, borates, etc., the tartaric acid preventing the precipitation of iron, alumina and chromium as phosphates or hydroxides. Part III. Add cone. HgSO^ and evaporate to dryness ; a carbon- aceous residue indicates organic acids or organic matter. All the acids mentioned, except phosphoric, boric and arsenic, may be removed by evaporation with HNO3 and ignition. Borates are soluble in a considerable excess of ammonium chloride and give no trouble. Arsenates are removed by reduction with SOj and precipitation as AsjSg by HgS. This should be done before adding HNO3. After making these tests, return to the main solution. * Formerly written (NH^^MoO^. SCHEMES FOR QUALITATIVE ANALYSIS. 261 Boil out HjS, if present. Add a few drops of HNO3. If H2C2O4 or organic matter is present, evaporate to dryness and ignite gently. If these are not present, but silicic acid is, then acidify with HCl and evaporate to dryness, but do not ignite. Treat the residue with HCl (cone), dilute with HjO and boil; it dis- solves wholly or leaves a white residue of SiO«. Filter. Residue 1°. Si02. Filtrate 1°. Nearly neutralize with NH4OH, dilute largely,* then add a moderate excess of NH4C2H3O3 and a little HC2H3O2, boil for about 5 min. and filter. Wash the ppt. with boiling water. Ppt. 2° Fe, Al and Cr as phosphates and basic acetates. Dry and mix with NaaCOs + KClOs, and fuse in platinum capsule. Dissolve the fusion in boiling water, and filter. Filtrate 2°. Metals of the 1°, 2° and 4® Groups, ex- cept iron. Analvze in the same way as any ordi- nary mixture of the first 4 Groups. Besidue 3°. Fe203, AhOst Fe2{P04)2 and Ah(P04)3. ( s t ( Solution 3°. NaaCrO*, Na2Ah04, etc. (Divide in 2 parts). V acidify with HC2H3O2; if any precipitate forms, it hows AIPO4); filter, and to he filtrate add Pb(OjH302)a, a rellow ppt. — PbCrO* ; proves )r. 2° acidify with HCl ; then add (NH4:2COs, and boil. A white, flocculent precipitate proves Al. If iron is not already present, in conRiderable quantity, add solution of FcoClfl until, on testing a few drops of the solution with NH4OH, a red precipitate is obtained. ■* « 2 £ fi. 65 a, £ cu £ S5 •I •Si pa < 2 * 3" .so. 6 ^ S w S « ii. B eS u 'O o ^ D 43 O rQ o « c "■^^ CO S (S O c8 8": a 9 O > bo o a o w . a o 5 e-cfe 3 P4 2 Pk 6 c5 + (5 uoiimiog U + o +1 -<QP4Q- £ c* JSl J* O S5Z + — — * — — ^ ••- oB »- g ^g8 Is * 2'2 £ S o g In 4d o ss iSo* V o o-S. a V g •S50 *S<M O -3 ©'«»• 6 6 u 6 91 e« -"^^ «^ Pk o 00 ^ X ^ Was 264 THE QUARTERLY. Table VII. Comparison of the Reactions of yd and \th Groups of Metals, Reagent. (NH4)2S fNH4^»S ppt. + HCl (dil.) (NH4^2S ppt. + HOiHsOa KOH KOH in excess. Cr,Og. Cr2(0H)ebl. gr.* CraCle Cr2(CaH80a)6 Cr2(0H),(bl.gr.) K2Cr204 (gr.) Cr2(0H>(bl.gr.) AlaOg. KOH in excess + N 11401 KOH in exces8'Cr2(OH)«(bl.gT.) and boiling ]!^H40H NH4OH iu excess Cr2(0H)«(bl.gr.) Insoluble NH4OH in excess Insoluble + NH4CI Na2COs Cr2(OH)«.(bl.gT.) Al2(OH)6 (wh.) AhClo Al2(C2H802)» Al2(0H)« (wh.) K2AI2O4 Al2(OH)6 (wh.) ZnO. K2A1204 Al2(0H)« (wh.) ZnS (white) (NH4)2C08 (NH4ViC08 in ex- cess BaCOj Na2HP04 KCN KCN in excess K4Fe(CN)e K3Fe(CN)6 XH4CNS Cr2(OH)g(bl.gr.) Insoluble Cr2(OH)«(bl.gr.) ;Al2(0n)fl (wh.) Cr2(P04)2 (bl.gr) Insoluble. Insoluble. Al2(0H)« (wh.) Al2(OH)o (wh.) Insoluble * ZnCla Insoluble Zn(0H)2 (wh.) (K2O, ZnO) ZnCl2, 2NH4CI fin dil. sol. t Zn(0H) 2 (wh.) Zii(dH)2 3(NH4)20,2ZnO ZnCl2, 2NH2CI Zn5^C03:2(OH)6 MnO. MnS(pink) MnCls Mn(C2H302)2 Mn(OH)2 (wh.) Insoluble Zn6(C03'2 OH)6 ' — . — ' (wh.) ZuCOs, NHs ** Mn(OH)2 (wh.) Incomplete Insoluble MnCh, 2NH4a MnCOs (wh.) MnCOa (wh.) Insoluble Cr2(CN)« (bl.gr.) K6Cr2(CN)i2 Al2rP04)2 (wh.) Al2(OH)o (wh.) ^ — . — ' Insoluble Zns(P04)2 (wh.) Mn3^P04)2 (wh.) Zn(CN)2 (wh.) |Mn(CN)2 (wh.) Zn(CN)2,2KCN Mn(CN)24KCN j I IZn2Fe(CN:6(y.wMn2Fe(CN)e(w.) |Zn3Fe2:CN)i2(y) Mn3Fc2(CN)i2(w) Na-iCOs + KC103,Na2€r04 (yel.) Na2Al204 (wh.) (fusion) fiorax bead in O.F. Emerald green. ,Na2Mu04(bl.gr.) 'Amethyst ** Not precipitated by BaCos fh)m cold solution unless present as sulphate. SCHEMES FOR QUALITATIVE ANALYSIS. , 265 Table VII. — {Concluded). Reaf^nt.. (NH4)«S CoS (black.) (NH>4)2S ppt. -f Insoluble HCKdil.) I (NHm/sS ppt. -|- Insoluble HCzHsOa I KOH Co(OH)2 (pink) KOH in excess NH4OH NiS (black) Insoluble Insoluble Ni(OH)2 (green) Insoluble Co(OH)2 (pink) FeO. FeS (black) FeCh Slightly soluble Fe(OH)3 (wh.) NH4OH in excess S0I.NH3 compounds NH4OH in excess CoGa, NH4CI -r NHCl NaaCOa Insoluble ilnsoluble Ni(OH)2 (green) |Fe(0H)2 (wh.) Sol. NHs comp'ds Insoluble (NH4I2OOS |NiCl2,NH4Cl FeCh, 2NH4CI 3Co(OH)2, C0CO3 (red) 4Ni(OH)2, NiCOs IFeCOs (gr. wh.) (grn.) ^ 3Co(0H )2, CoCOs (red) (NH4)2C08 in ex- Ck)COs,(NH4)2COs cesa BaCCb ** NajHPO* KCN KCN in excess 4Ni(OH)2, NiCOa FeOOa (gr. wh.) ^ . ' (grn.) I — . — ' NiC03(NH4)oCX)3 Insoluble FeS (blk.) FeCl2 Slightly soluble Fe2(0n)e(red) Insoluble Fe2^0H)e(red) «* Co3(P04)2 (lilac) ** Insoluble Insoluble Fe2(OH)« (red) Fes'vOH). (red) Insoluble Fe2(0H:. (red) !Ni3(P04;2 (green) Fe3fP04)2 (wh.) Fe2(P04)2(wh.) I ^ Co(CN')2 (brown wh.) Ni(CN)2 (yol. gr.) ,Fe(CN)2 (yl.rd.) Fe2(0Hl. (red) Co(CN)2, 4KCN KflCo2(CN)i2 KCN in excess + KOH + Br, or HgO KN02 + CH2H502 KflCo2(N02)i2 (yellow) K4Ni(N02^e Ni(CN)2, 2KCN i Fe(CN)i, 4KCN Ilnsoluble Ni2(0H)« (black) K4Fe(CN)e K3Fe(CN)« NH4CNS Borax bead inO.F. (bl.wh.) Co2Fe(CN), (gr. grBy).;Ni2Fe(CN)o(gr.w.)|K2Fe"Fe(CN)6 Ck)3Fe2(CN)i2 (brown) NisFezJCN)^ (gr.) Fe3Fe2(CN)i2 1' . ' I ' . ' (yel.)i ' . '(bl.) I Deep blue. Violet-brown. .Yellow or grn. VI Fe4[Fe(CN),]3 ^ , ' (bl. Fe2(CNS)c (red) Yellow or grn. • b., bl. — blue. g., gr., grn. — green. w., wh. _ while. bl., blk. — black. y.. yl..-yel. — yellow. l»r. — brown. ** I^ot precipitated by BaCos from cold solution unless present as sulphate. gy. « gray. 266 THE QUARTERLY. Scheme V. — Separation of the \st and 2d Groups, Filtrate 23. Evaporate to small bulk, and make slightly acid with HCl. Filter out separated S. To the filtrate from this, add NH4OH to alkaline reaction, then (NH4)2 COb in slight excess ; warm and filter. Wash the ppt. Ppt. 35. BaCOs + SrCOs + CaCOj. Dissolve in the least possible quantity of hot, dil. HC2H8O2 (36), and test a small portion of the sol. for Ba, by ad- dition of CaS04. An immediate ppt. shows Ba. If no ppt. forms at once, al- low to stand 10 min. The appearance of a ppt. OD standing will indicate Sr. If Ba has been found by the above test, add to the main part of the sol., KsCrOi* in slight excess; allow to stand a few minutes, filter and wash. (If Ba is not found as above, omit tliis treat- ment, and proceed to test for Sr and Ca, as below). Filtrate 35. MgClj, NH4CI -f KCl -f NaCl + traces of Ba and Ca -f- NH4 Salts. Divide into 2 parts, f Part 1°.— Add a little (NH4)2S04, and then a little (NH4)20i04; a white ppt. shows traces of BaS04 H-CaC204 (43). Filter. To the filtrate add NH40ir and NasHP04. A white, crystalline ppt. shows MgNH4P04 (44), and proves Mg. Part 2°. — Evaporate to dryness, and ignite, to expel all NH4 salts. Dissolve residue (45) in a little water, and filter. Evaporate the filtrate to very small bulk, and make the fiame-test for Na. Then add a few drops of HaPtCIe to the solution, and stir with a glass rod. A yellow, crystalline ppt. shows (46) KzPtClft, and proves K. Addition of alcohol increases tlie delicacy of this test. Ppt. 37. Ba CrOi (yellow). Confirm by diss, in dil. HCI, and add dil. H2S04. A white ppt. shows BhS04, and proves Ba. Filtrate 37. Sr(C2H80»)« + Ca(C2H302)t. Add NH4OH to alkaline reaction, then (NH4)3C03 in slight excess, heat and fil- ter; wash thoroughly. Ppt. 38. Sr,C08 + CaCOs. Dissolve in hot dil. HC3H8O2. Divide solution into two parts. FiLT. 38. NH4 salts. Reject. Part 1°. Add a solution of CaS04« warm and allow to stand some time. A white ppt. = SrS04. Moisten ppt. with HCl (cone) and test in the flame. Crimson flame proves Sr. Part 2°. Make alkaline with NH4OH, then add a con- centrated solution of (NU4;3S04 boil for some minutes and filter. Ppt. 41. SrS04 + CaS04. Filtrate 41. Add NH4OH -K (NH4)2C204 and warm. A white ppt.= CaC204 — proves Ca. • Prepared from KjCrjO? by adding NH4OH until the color changes to yellow, t NII4 is to be tested for in the original solution by beating a portion of it with KOH added to alkaline reaction. fBa , ICa- r Ca(C2H30-i)2 ( HCaHsOi SrS04. Ppt f SrSOi 41 tOftSO*? rC:iS04 1 Ppt.42^0ftCr04, •41 iifn^ffih [+(NH4).(M)4 Sol.42{NH4 8alte. [ NH4OH J (Mi Na SCHEMES FOR QUALITATIVE ANALYSIS. 267 Table IX. — Comparison of Reactions of the ist a?td 2d Groups of Metals, SECOND GROUP. Reagent. BaO. KOH NH4OH NH4OH+NH4CI (yH4)iCOs NasCXb NaaHPO* Na«HP04+NH40H +NH4CI (NH4)»C204 H«S04(cin.) or \ Solable sulphate j OASO4 KaCrsOr HzSiFe Chlorides -{- Alcohol In cone. sol. B»(OH2(white) Ba CO3 (white) SrO. In cone. sol. In cone. sol. Sr(0H)2 (white),Ca(0H)2 (wh.) CaO. SrCOs (white) MgO. BaCOs (white) jSrCOs (white) BaHP04(white) SrHP04 (white) Ba3(P04)2 * — ^ — ' (white) BaCa04 (white) BaS04 (white) (Immediately) Sr3(P04)2 ^ — . — ' (white) SrC204 (white) SrS04 white) (Slowly) CaCOs (white) CaCOs (white) CaHP04 (white) Mg(0H)2(white) Mg(0H)2(white) ^- y '* incmplt MgCl2, NH4CI Mg4(C08)8(OH)2 ' . ^(w.) MgHP04(white) Nitrates + Alcohol Flame BaS04 (wbite) SrS04 (white) BaCr04(yel.) BaSiFe (white) Insoluble Soluble ti Insoluble Yellowish -gre'n Crimson Ca3( P04)2 ' MgNH4P04( wh) (white) !' . ' CaOi04 (white) CaS04 (white) Soluble (( Yellowish-red. Soluble <( FIRST GROUP. Reagent. K2O. H2PtCl6 H2C4H40e NaHC4H406 K2H2Sb207 KOH Flame On ignition NaiO. KaPtCle (yel.) NaaPtCU KHC4H40«(wh) KHC4H406(wh) Violet Fixed Na2H2Sb207(whi (NH4),0. (NH4)2PtCIe(yl.) (NH4) HC4H40« (white) (NH4) HC4H4O6' (white) Intense yellow Fixed NHj Voiatiie 268 THE QUARTERLY. Scheme VI. — Acids. Boil the solution containing the acids, with excess of Na2(X>s ; filter hot. * Precipitate A. Contains bases and perhaps silicates, phosphates and flnorides. Divide into two parts. Part 1°. Acidify with HNOs, and evaporate to dryness. Take up the residue with HNOs and HaO ; filter and wash. Part 2°. Acidify with HOiHsOa, and filter. Residue 1^ Filtrate 1' A white, gritty i Add(NH4)6Mo7024 powder = SiOa. Test with nieta- phosphate bead. a yellow crystalline ppt., = UsPO^. Filtrate 2®. K^ect. Residue 2°. If no Si02 has been found in resi- due 1°, treat residue 2° with H2SO4 (cone.) in a Pb or Pt dish, and see if fumes will etch glass ; if they do = HF. Should SiOa have been found in residue 1°, treat 2° according to Fres., \ 146, 6 for HF. Filtrate A. Contains the acids. Divide into two unequal parts. Part1° (I of a.) Add HNOs to fainily acid reaction ; then NH4OH to slightly alkaline reaction, and boil until all free NH4OH is driven olf. Divide in two parts. Part 1*. Part 2*. Take a small portion of! Take a small portion of this neutral solution, and; this neutral solution, add add BaClz. A whiteppt. ^ AgNOa, and then acidify acids of Group 1. To this with HNOs. Ppt. -^ acids ppt. addHCl; all dissolve! of the 2d Group. Note the except BaS04; proves H'iS04 color of the ppt. before and after adding HNOs. Part 2° (i of A). Evaporate to small bulk, cool and acidify a portion of this solution with cone. H28O4, and test for HNOs with FeS04. Brown ring = HNO3. HC10.^,HBr,HI and HiCr04 impede this reaction, and should be removed. Fres., g 192, 5. Test 2d portion for HClOs see Fres., § 160, 5, 6, 7. SCHEMES FOR QUALITATIVE ANALYSIS. 269 Scheme VI. — Coficludcd, It Group 1° haa been found by test on part 1% take the remainder of this solution and divide into five part8: 1°. Acidify with HC2H8C)2, and ad<t a solo- tiou of CaS04; a white pulve- rulent pptv =- CaCV)4 = H.iC204, Co n fi rm by testing another portion of the solution witli MnOa + H2SO4 (dil.). 2°. Acidify with HCI, and test for H3BO3 with tunnerii- paiier. A red color = HsBChu Evaporate the same solution to dryness, and take up residue with a little HCl and water a white insol. ' residue = SiOz' 3°. AddCnCIj 4°. Acidify andalittleNHi-'with HNOs.add OH ; filter ppt.if,(NH4 «Mo7(>24, a any ; dry, and if yellow ppt. = 8i02 has not'HsP04. IfAssOs been found in 2^ I has been found, test for HF by in the test for etching test. If bases, it should SiOs has been found, then test be removed bv acidifying with 5. If H2Cr04 is present, the solution will be yellow. Confirm by acidifying with HC2HsOa, and adding Pb(C2H804)2, a yellow ppt. = PbCr04. accor<rg to Fres. I H('l, passing in ^ 146, 6. 'H2S gas, and fil- jtering before {testing for HsP04. HCI. When HI,HBr,H4FeCy«,HeFe2Cyi2 and HCy have not been found to be present, a white curdy ppt. on addition of AgNOs insoluble iu HNO3, and soluble in NH4- OH = HCl. HCl may also be tested for by means of H2SO4 and MnOs. See Fres., ^152,6. If HI,HBr,HCy,H4FuCyfland He- Fe2Cyi2 are present, see Fres., ^ 157, for detection of HCl. H2S. If present, will*be found on acidifying the sodium carbonate solution with acid, when H2S will be given off, and will turn paper moistened with Pb(C2Hs03)2 black. H2S is usually found in testing for the bases, as it given off when dissolv- ing the oiiginal substance. See Fres., § 180, 2. If 2d Group has been found to be present by test of Part 2*^, test remainder of solution for acids of this Group as follows: Divide into four parts. 1. 2. 3. Add a little CS2J Acidify with HCl, I Acidify with HCl and then a fe wand test with FeS04, and add Fe2Clfl; drops of HCl, then a blue ppt. = a bine pppt. = NaCIO very care- Hrt(FeCy«)2. The H4FeCye. fully ; the I is set FeS04 solution must, free, and colors CS2,be reciutly made, purple ; add more NaClO very care- fully, and finally the I color disappears, and the Br is then liberated and colors CSj brown. 4. Acidify slightlv with H2SO4 and if HCy is present, it is known by its pecu- liar odor. Cure should be taken not to inhale this gas. Test for HCy. See Fres. {J 155, 6. If H4FeC.V6, or Ho(FeCy« 2 have been found in 2 and 3 test for HCy, as given in Scheme for 2d Group acids. H2COJ. H2C4H40», etc. Test the original solution with Ha; if I H2C4H40«h HsGjHfiOT and HC/2n30t. effervescence, pass the gas into lime wa- For these acids, follow Fres., ? 193. ter. A white ppt., soluble in llOilliOt, with effervescence proves H2CO3. To see if 6rganic acids are present, evaporate the neutral solution to dry- ness; and ignite gently. A carbonaceous residue = organic acids, or organic matter. VOL. XV.— 19 270 THE QUARTERLY. Alternate Scheme for Separating and Detecting HCv, H^FeCy^, H^FejCyij, HCl, hi and HBr. To a portion of filtrate A add NaHCOj and distil, carrying dis- tillation to dryness and pass the distillate into KOH, test this for HCy in the usual way ; when cyanides are removed, cool, dis- solve residue in HjO, acidify very slightly with H^SO^ and add CuSO^ as long as a ppt, is formed, and until the liquid becomes blue or green ; filter. Ppt. CuaFeCy* CusFe-iCyw Note. — Test for these acids iu the original solu* tion with ferric and ferrous salts. FiLTBATK. Add cone, solution of (NH4)2Fej^&04)4, and boil ; pass vapor into starch -water. Blue color indicates HI; when this is re- moved, add a drop of cone. HtiSOi, some dil. KzMnzOtt, and boil as Ions as Br is f^iven ofi*, adding more KjMuzOs until color no longer disapitears. Finally test solution with HNOa and AgNOs, a white curdy ppt. sol. in NH4OII and repptd. by HXOs, indicates HCl. SCHEMES FOR Q UALITA TIVE ANAL YSIS. 27 1 2/2 THE QUARTERLY. % c ^ V -s^ ::: Qi ,K i^ • (5 •^s Jz; M » « ^ 3 ^ '5 S ••* •1 <3 J2 • ^^ ^ ^ ^ "»2 « "^ 5 « ^ ^ ■5 Si ^ "^ ^i^ OQ « fi X °8. 0) a (4 ^l3 .M V « a t o >» f a n 1 n o 9 .a OB — 3 ^ a 1 a I] ^ ^ O VMM O •>« a *3; fa M M 0) 8 •« -^® ^^ *a *a 0*0 "o >r. a u be e« a C -< -* GO 8^ t S 3 be o = ■% r • a eg 5 o w (5 o o e o O o bo 3 is !« .5 m 6 6 c c5r JZ5 5 O K i + + 6 O 04 + CO 73 S 1 o a O o Xi O u SCHEMES FOR QUALITATIVE ANALYSIS. 273 Table XII. — Organic Acids, Oomparisen of the Beactions of Tartaric Citric, and Acetic Acids. Salts •f tkese Acids separate Carbon on ignition. ReagenL GaCIi i« excess. H.C4H4CV1 H8G6H»07 <::»C4H«Q8 (white) <^{C^l&^)i* CaCli ppt -)- KOH ,8ol(re-ppt. om boilinf ) Insoluble. (cold) Lime wat«r (€aH202) CaC4n4Q6 (white) in exreas. > ^ KCiHiOrfHCjHjOa KHCiH40« (white) A;?NOs. Agj^SiOa (white) AgNOs ppt. dis- \ ^ » ' solved in K^HiOH \ 'Ag (silver mirTor) and gently heated ) . -y- On ignition Odor of btirnt asgar. f Heated with oonc. \ H2S04 Black residue ■«**••••• ( Heated with oonc. \ \ H3BO4 and alcoltol \ FeS04 4- KOH f- (violet solution.) HaOz or Nuaol Xo ppt. ia c«ld sol. Ppt. «u boiling AgsCya^Or (white) HCaHsOs JBlack residue (€Os) given off, •• *«••••• HC2HSOJ (volatil- izes) C2H5fC2lLtOj)acetic I ether given off * Soluble Id ^1X401, and re-precipUated on boiling. 274 ' THE QUARTERLY, Table XIII. — Solubilities. Name of Salt. Carbonates Salphates Sulphites Sulphides Nitrates Nitrites Chlorides Chlorates Hypochlorites Iodides Fluorides Phosphates ) (Ortho.) i Silicates Acetates Oxalates i Tartrates Citrates Arsenites and Arsenates Chromates 6olu))le in Water. Alls-allne cax'bonates. f All sulphates except \ those in 3 and 4 3. Soluble or decom- posed by acids. 4. Insol. in Water and acids. All Some basic sulphates, B^SO*. SrSO,. CaS04,PbS04 'Alkaline sulphite!* and AH salphites are de acid sulpltitesof al- kaline earths. I Sulphides of the alka I lies and alk. earths. f All except some basic \ nitrates. composed l>v acids, yielding (S6j). All ; some by HCl. HaS evol. ; olhei's by HNOsjor aq.r. S. Some basic n it rates sol. in dil. HNOs. All 1 All except tlK>se given ^ /f7 ^if^Y'^T^^^f^^^^^^^f^^ i« -^ a.wl J *"" HgaCia> Cu«Cl.iv (HeaClaSol. in iiidand4, p^^,,^^ HNOaorCl). All All All except those given Ajrl,. 1*1)1^ Hg2l2jAgI. Hgala, decom- in 3 and 4. CU2I3, Hgls. [ posed by CI. Those of the alkalies, ^^n j j 1 and a few otiiers: *» deeon,pn«e<l by AgF, HgPfc *""'>"8 ^'^<^*- Those of the alkalies. f Potassic and sodic sili- 1 catea (not native). All normal All Many are decomposed Many native sili- by acids separating! catcs decomposed H^SiOi. by HF. All {Those of the alkalies and Cr and Sn^MMg All and Fe*« sparingly). f Normal alkahne tar- \ trates. Alkaline citrates. |A1> All Those of tbo alkalies. All f Those of the alkalies ^n „.,| -. an<l Sr. C», Mg, Zii. A": "'"' » '«" "^^'^^P' I. Feta Cu. tions. ABSTRACTS. Analytical Chemistry, by E. Waller, Ph.D. Determining Metals as Oxides. Schmidt {Ber. xxvii., 225). It is often convenient and desirable, after separating some metals as sul- phides, to convert them to oxides for weighing. Experiments made by igniting the sulphides with HgO, gave results always somewhat high, due to retention of some basic sulphate. Igniting with HgO and Hp(N03)2 ^^s better, but still showed a little too high. But when a solution of Hg(CN), and ammonia was added, and the material heated finally to intense ignition, excellent results were obtained. Test analy- ses were made with Cu. Zn, Bi, and Fe. Incidentally, the formation of the compound Hg(CN)2NH, was observed. Barium and Strontium in Rock Analysis, Hillebrand (J. Am, Chem, Soc.y xvi., ?^^^, When much Ca is present, all the Sr, if small in amount, will precipitate with the CaQO^, especially if the excess of (NHJ2C,0^ added is very decided. Unless, however, the Ca largely pre- dominates, some Sr escapes precipitation. In the case of Ba, when large amounts of Ca are present, if a rather slight excess of (NHJ^C^O^ is added, and alkaline chloride is present, practically all the Ba will re- main in solution. (The author gives no warning of the possible pres- ence of sulphate in the (NH^\C,0^ ordinarily supplied for laboratory use. — Abs.) The Ba, thus escaping precipitation, will usually also more or less completely escape* precipitation as phosphate along with the Mg precipitate which ordinarily follows. Examination of Zinc- Ores, Jensch (Z/j. /. Angew. Chem,, 1894, 155). Blendes containing zinc silicates were encountered which often failed to surrender to solvents 7 to 10 per cent, of the zinc present. The remedy was found to be fusion with alkaline carbonates in order to effect solution. Manganese J Review of Methods, Saniter {J, S, C /, xiii., 112). Geographically, the methods used are stated to be in general terms; in England, Pattinson's method or Riley's modification of the same ; on the Continent, Volhard's method; in the United States, the pyrophos- phate (gravimetric). The gravimetric determination as MUgO^ is stated to be more or less in use in all countries. It was found practically im- possible to obtain theoretical MngO^. An average of 20 lots of ignited precipitates contained 71.4 per cent. Mn against theoretical 72.05 per cent Mn. (In the discussion, reference was pnade to the point noted by Messrs. Pattinson that the thickness of the crucible, the temperature of ignition, and many other points, apparently trivial, made a difference in the composition of the precipitate when weighed.) Ignition, when ammonia had been insufficiently washed about, also gave low results. Volatilization of some Mn under these conditions was asserted, but proof of this point was not very clear. The pyrophosphate method, as de- scribed by Blair {Analysis of Iron and Steel^y was found to be the most 276 THE QUARTERLY. accurate. The possible presence of Ca or Mg (derived from reagents or apparatus) may give high results. The remedy consists in separating as MnS, dissolving, and then precipitating as NH^MnPO^. Obtaining a perfectly crystalline precipitate, and washing with cold ammoniacal NH^NOj. are insisted upon as indispensable for accuracy. Volhard'^s method is described as consisting in separating the iron, etc., by basic acetate, separating the Mn from the filtrate by Br, and dis- solving this (ignited) precipitate in HCl, neutralizing with ZnO, and titrating with carefully standardized permanganate solution. The results were found to be a little low, " as there is always a doubt as to the pre- cipitate being absolutely all Mn02." PattinsorC s method — precipitation as MnO,, and titration with FeSO^ (see Quarterly, xii., 336), gave results lower than in the case of the Volhard, and requires that one*s method of working should be standard- ized upon Mn oxide of known composition. It was noted that though different chemists differed from each other, each chemist agreed con- sistently with himself. In the discussion, Mr. Gray spoke of .higher re- sults being obtained by chemists in the United States than in England. This assertion was not accepted by another speaker. Nickel in Nickel Steel. Campbell {/, Am, Chem. Soc, xvi., 96). In a 500 c.c. flask, dissolve 2.2222 grammes of the steel in 20 c.c. HNO, (Gr. 1.2) with 5 c.c. HCl (Gr. 1.21). Boil until the solution is clear, remove from the heat; and add 155 c.c. Na,HPO^ solution (200 grammes crystallised, in i860 c.c. of water). If any precipitate forms, redissolve by a few drops of HCl, add 25 c.c. HC^HjO^ (Gr. 1.04), then 100 c.c. NaCjHjjO, (250 grammes in 820 c.c of water), shake, dilute to 502.5 c.c, shake, and let stand fifteen minutes; filter through a large dry filter, catching the filtrate in a dry beaker. When enough has run through, draw off 250 c c. of the filtrate, which represents one-half of the amount taken. (The volume of the Fe,(POJj has been determined to be 2.5 c.c.) Boil, and add 20 grammes KOH, dissolved in 40 c.c. of water. Boil five minutes, and then keep hot until the precipitate settles well. Filter the precipitate (containing all the Cu, Mn, and Ni) through asbtstos, decantiiig as much of the solution as possible before getting the precipitate upon the filter. Wash with water. Dissolve the precipi- tate in 6 c.c. of strong HCl with an equal volume of water. Wash with a little water. The whole solution should not exceed 50 c.c. When at a temperature of 40° or 50° C, add 15 grammes granulated Pb (pte- viously washed with HCl), and agitate lor five or ten minutes. This will separate Cu. Filter through glass wool, wash, and boil down to 60 c.c, add 10 c.c of the Na^HPO^ solution, then ammonia until a pre- cipitate just forms, then HCl to just clear it, cool, and place in a flask graduated to iii.i c.c Add 5 c.c strong ammonia, dilute to the mark, shake, and let stand fifteen minutes. This separates Mn and Pb. Filter through a 9 cm. filter. Take 100 c.c. of the filtrate = i gramme of steel for determination of Ni. electrolytically or volumetrically. For the electrolysis, add 5 c.c of strong ammonia, dilute to 175 c.c, and elec- trolyze. The volumetric method is essentially that of Moore {vide Quarterly, x., 373, and xi., 70), with Cu,FeCyg indicator. Nickel in StecL Westesson. {^J. Am, Chem. Soc, xvi., 1:0.) Dis- ABSTRACTS, 277 solve I gramme of the sample in 20 c.c. H^SO^ (Gr. 1.16), and boil for some time, after a while adding 5 c.c, of HNOj, a little at a time. Evaporate to expel the HNO,, cool, dilute and heat until clear. Nearly neutralize with Na^COj, dilute to about 400 c.c, then add NaQHjOg, and precipitate basic acetatfes, redissolve and reprecipitate twice more. Evaporate the united filtrates to 400 c.c., add to the hot solution 10 c.c. strong ammonia, boil, and filter off HjOjMnO,. Then electrolyze for Ni. Separating Cobalt and Nickel. Herrenschmidt and Capelle. {Fres. Zts.Anal, Chem,^ xxxii., 607.) The nitrite separation was found by -these authors to be unsatisfactory and incomplete ; the cyanide method was bet- ter, but not altogether satisfactory. The method they regarded as more complete consists in suspending the hydroxides in soda lye and warming to 50° C. while passing a current of CI. Ni goes into solution while Co remains undissolved. The method recommended, after removing H.^S, and separating Fe and Al bv repeated precipitations with (NHJ^COj, is to add (NHJjS. Let stand, acidify with HC^HjOj. boil, filter, wash with NH^CjH^O, solution, dissolve in HNOj, and divide the solution in halves. One-half is evaporated to dryness, the residue moistened with HjSO^, and the Co and Ni together weighed as sulphates (ZnSO^ might also be present). The second half is precipitated by KCy and Br, as recommended by Fresenius, and the Ni2(OH), treated with NaOH and CI, as suggested above. The solution of Ni is acidulated with HCl, and after boiling out CI, is poured into NaOH solution. This is redis- solved in HCl and evaporated to dryness, finally moistened with H^SO^ and weighed as sulphate. The Co is obtained by difference. If Zn is present, the salts from the first half are dissolved, and the Zn separated by Wohler's KCy method, after which it may be estimated. Commercial Copper — Foreign Metals, W. Hampe. ( Chem. Ztg,^ xvii . , 1 691.) The main feature is the separation of Cu as Cu2(CNS)2. Dis- solve 25 grammes of the sample in 200 HjO, 100 c.c. cone. H^SO^ and about 45 c.c. HNO, (Or. 1.21). After solution, add 200 c.c. more HjSO^, filter from PbSO^ (with Cu and Bi antimonates^. Make a sep- arate examination of this precipitate. Warm the filtrate to 40° C, pass SO, until all N oxides are expelled and the solution smells strongly of SO,; add two drops HCl and filter off AgCl, add KCNS, pass SO, again, dilute to two litres, filter off 1800 c.c, evaporate out the SO, and exam- ine for foreign metals. An allowance must be made for the volume of the Cu,(CNS), precipitate. 25 grammes of Cu will afford a precipitate having a volume of 15,983 c.c. Impurities in Pig- Copper^ etc, De Benneville (^J. Am, Chem. Soc., xvi., 66.) Thie author has sought to manage in such a way that the major part of the predominant constituent would be left in solution, and a comparatively small precipitate containing many of the constituents sought would be obtained. A method giving this result partially con- sists in dissolving, say 10 grammes of the material in HNO,, removing any large excess of acid by evaporation, adding ammonia in sufficient excess to form soluble cupro-ammonium salts, diluting to about 150 c.c, and then adding an excess of BaO,. The precipitate may then be fil- tered off, and well washed with dilute ammonia, to remove copper salt. 278 THE QUARTERLY. The separation of Pb, Bi, Sn, Fe, Mn and Sb is complete. Ag, Zn and Cd can be separated from the filtrate by decolorizing with KCy and passing H,S. On account of the dilution, the method is only qualita- tive for As and P. Electrolytic Separation of Lead and Copper, Classen. {Ber., xxvii., 163.) The solution (75 c.c), containing 20 c.c. of HNO, (Sp. Gr., 1.35 to 1.38), is electrolyzed hot (50 to 60° C), with a current of i.i to 1.2 amperes (ND,oo ^-5 ^^ '•?) ^^^ *" hour. By this means 98 to 99 per cent, of the lead is deposited on the anode as PbO.^, while no Cu is deposited on the cathode. The solution, transferred to another weighed dish, is then over-neutralized with ammonia (until the blue color ap- pears), and then 5 c.c. of nitric acid is added, and it is diluted to 120 to 150 c.c. After standing until it becomes perfectly cold, it is electro- lyzed for 3 or 4 hours with a current of ND^^^, i to 1.2 amperes. In this the remainder of the Pb is deposited on the anode, while the Cu sepa- rates on the cathode. PbSO^, if present in the liquid to be analyzed, can be brought into solution sufficiently for the purposes of the first deposition by treating with a little ammonia, and then pouring the mixture into the 20 c.c. of hot HNO3 ^^ ^^^ capsule. « Electrolytic Separation of Lead. Kreichgauer. {Ber.^ xxvii., 315.) The most favorable conditions were found to be a solution containing I part of free HNO, (Sp. Gr. 1.4) to 7 parts of water. The precipitate should be washed twice with alcohol before drying and weighing. Re- sults somewhat variable were obtained when only water was used for washing, the reason being, apparently, that the removal of all free acid by this means was not easily made complete. Volumetric for Lead — Estimation in Tinned Ware, Bsiyrac (f.BAarm, CAem,, xxviii., 500.) A standard solution of Na,HPO^ (in crystals) (11.922 grammes per litre) is used, which is standardized by Pb(NOj,), solution (15.99 grammes per litre), i c.c. = 0.01 gramme Pb, and should require i c.c. of the phosphate solution. The operation is conducted in a solution containing acetic as the only free acid. The end reaction is determined by a spot-test with a (10 per cent.) solution of KI. (Fail- ing to show yellow Pbl^ when all Pb has been precipitated.) For tin, dissolve i gramme in HNO, ; evaporate ; digest the residue with 20 c.c. water and 20 c.c. of (10 per cent.) soda-lye for ten minutes; filter off, acidulate slightly with HNO3, evaporate off the excess, add 3 c.c of (3 per cent.) NaC^HgO, solution, and titrate. If much Pb is present, the test-solution should be five times as strong as the above. Volumetric for Si her. Deniges. (C -^^«//., cxvii., 1078). A stand- ard solution of KCy of about i per cent, strength is used. This keeps remarkably well, its stability being increased by the presence of free alkali. A standard solution of AgNO,, the value of which is known in terms of the KCy solution, is necessary. On taking 20 c.c. of the KCy solution, the addition of the AgNO, solution fails to give any turbidity until enough Ag salt to form the double cyanide (KAgCy,) has been added. For this purpose the solution must be exactly neutral, but it ABSTRACTS. 279 has been found that a sharp end-reaction may be obtained if the solu- tion contains free ammonia and a little KI. If, then, we dissolve a weighed quantity of the argentiferous substance in 20 c.c. of the KCy solution, it requires less of standard AgNO, to produce the end-reac- tion. The amount recommended to be taken for examination is 150 to 200 milligrammes (one-thousandth of an equivalent of the compound present). Approximate Determination of the Equivalent of Rare Earths. Kriiss and Loose {Zts. f. Anorg, Chem./\w,^ 161). By adding an excess of standard oxalic acid to a weighed quantity of the oxides, filtering, and titrating the excess of HjCjO^ remaining in the solution with standard permanganate, constant results were obtained. The operation did not seem to be sensibly affected by solubility of the earthy oxalate, but for some unknown reason gave rather high results. When the results were calculated on the assumption that the precipitate contained 17 equiva- lents of the rare earth metal to 16 equivalents of oxalic acid, the values obtained were fairly in accord with the atomic weight determinations made by weighing as sulphate. Separating Cerium from Lanthanum and Didymium. Bricourt ( C. Rend., cxviii., 145). In a slightly acid solution of CeCO, in HjCrO^ an electrolytic current of 2.5 to 3 volts gave an immediate deposit of CeO,,- 2CrOj,,2HjO on the positive pole as brilliant orange-red crystals. La and Di give no corresponding deposition even when present in a solu- tion from which Ce is being deposited. r Thorium Separation. Dennis and Kortright {Am. Chem. Jour., xvi., 79). Potassium hydronitride (KN,) when added to a nitric acid solu- tion of a mixture of the rare earths from monazite which had been nearly neutralized with ammonia, gave a white gelatinous precipitate, consisting apparently of pure thorium hydroxide. Colorimetric for Vanadium, von Klecki {Zts. f. Anorg, Chem.^ v. 374). A solution of V^Og in cone. H^SO^ becomes green or blue by addition of grape sugar. Iron under these conditions gives a colorless solution. The method may therefore be used as a colorimetric test in presence of considerable quantities of Fe. Separating Vanadium from Chromium, von Klecki {Zts, f Anorg. Chem., v., 381). V^O^ as well as CrO, may be precipitated by uranium salts from a neutral solution. If free acetic acid is present, and the solution is boiled the chromate remains dissolved while the vanadate is precipitated. After standing for 12 hours it may be filtered and washed, etc. Iodine in presence of Bromine and Chlorine. Groger {Zts. Ang. Chem. , 1894, p. 52). Weigh out, dissolve to a definite volume and take a meas- ured portion not containing more than 0.050 gramme of I, render neu- tral or slightly alkaline, place in a flask on the boiling water bath, and run in solution of potassium permanganate (i in 25) until the pink color is permanent. The reaction occurring is : KI -f K2MnjOg -f H^O- 28o THE QUARTERLY. =s KIO3 + 2KOH + MnO,. No corresponding reaction occurs with bromide or chloride under these conditions ; add a few drops of alcohol and heat until colorless. Filter off MnO, and wash well, and to the cold filtrate add a solution containing about 0.5 gramme KI free from iodate and acidify with HCl. The reaction occurring is KIO, + 5KI + 6HC1- = 6KCI -f 3H,0 + 3I,. Titrate with tenth normal Na,S,0,. One- sixth of the I thus found has come from the substance tested. If ammo- nium is present in the original substance, it must be removed by adding excess of KOH free from nitrite and heating, before adding the K,Mn,Og, otherwise it would form nitrite in the solution and occasion high results. The solution should not be too strongly alkaline when permanganate is added, or a partial reduction (formation oi green man- ganale) will occur. The method may be applied for determining the purity of sublimed iodine. Boric Acid in Wines^etc, Kulisch {Zts,f. Angew Chem., 1894, 147). The solution should be as concentrated as possible, and needs only to be decidedly acid. The red coloration of tumeric paper is only decisive for B,0, if it turns blue-black on treatment with alkaline solutions. The presence of fixed alkaline chlorides is detrimental to delicacy of reaction, but this is obviated by the use of a little phosphoric acid along with the HCl. Phosphorus in Coal and Coke. Lychenheim {Trans, Am. Inst. Mi n, Eng.y Virginia Beach Meeting, Feb., 1894). The most rapid method, which afforded results quite as accurate as more elaborate methods, con- sisted in burning the coal to ash in a boat made of platinum foil 2 inches square and ^ inch deep, and boiling the ash with 40 c.c. of strong HCl, evaporating down to 10 c.c. adding 40 c.c. of HNO^, (Gr. 1.42) and evaporating to about 20 c.c. diluting and proceeding as in the case of ores. Phosphorus in Steel. Dudley and Pease {J. Am. Chem, Soc, xvi.). When it is required that duplicates shall agree within one- or two-thou- sandths, the ** acetate method " {vide Blair), or, as some call it, ** the citric acid method,'* is inaccurate. In this method, if but little Br is used, to afford a minimum of ferric salt to carry down P^Oj, some P^Oj does not accompany the basic acetate precipitate; also, some P^Oj may fail to go into solution when this precipitate is treated with HCl; fur- ther, in the final precipitation, the Mg mixture fails to precipitate P^Oj completely. This last feature was not entirely absent in other cases where citrates were not present. For very accurate results use 10 grammes of the sample, and carry it on, as described by Blair for the *' acetate method," up to the point of adding Br. Then add enough Br. to oxidize full 0.5 gramme Fe, con- ducting the basic acetate separation in other respects as usual. Dissolve in HCl, evaporate to dryness, take up with strong HNO,, evaporate again, then take up with diluted HNO3 (Gr. 1. 13), and precipitate with molybdate. Dissolve the precipitate in ammonia, saturate this solution with H,S, acidify with HCl, and filter off MoS^ (with As sulphides if present), wash, concentrate filtrate and washings to small bulk, and pre- cipitate with Mg mixture. ABSTRACTS. 281 As to the molybdate precipitate (yellow precipitate), some reasonable doubts exist as to whether it contains all the P when formed in presence of much Fe. Also, the ratio of MoO, to P in this precipitate seems to yary accord- ing to the character and proportions of ammonium salts (and other) when precipitation is effected. Different methods of reducing the MoO, in the precipitate also afford different results when the volumetric method is used. These points might be elucidated by experimenting on known amounts of the pure yellow precipitate, but, to obtain it unaltered, by drying, etc., in a form adapted for weighing out, etc., is attended with difficulty. The necessity for determining these points may be evaded by using a volumetric method, in which the permanganate solution has been standardized with a steel in which the P has been determined gravi metrically. With constant conditions, the results are always con- stant. Graphite in Pig-Irons, Crobaugh (/, Am, Chem. Soc.^wi.^ 104) quotes experiments which indicate that when 5 grammes of the pig-iron were dis- solved in 125 c.c. of HNO3, with 12 c.c. of 40 per cent. HFl, aud heat- ing until solution was effected, then filtering through a pair of counter- balanced filters 9 cm., washing off the iron with water, and then wash- ing out the hydrocarbons, etc., with ammonia (i : 3 by volume), only graphite remained on the filter, in amount corresponding to the more elaborate combustion method. Determined by drying and weighing, afterward igniting to obtain residual mineral matter (SiOj, etc.). Wash- ing with diluted ammonia seemed to replace p)erfectly the washing with KOH, alcohol, and ether, usually deemed necessary. Determining OxaAc Acid, Gunn (^P harm, J, and Trans, ^ liii., 408). A solution of ferrous phosphate, containing an excess of HgPO^, is col- ored yellow by oxalic acid, and this reaction is used as the basis of a colorimetric method of estimation. Precipitating Barium Sulphate in Presence of Silica. Sleeper {C, N,, Ixix., 63). The results of a number of trials go to show that SiO^ is not co-precipitated with BaSO^ under the conditions ordinarily obtained in, say, examination of pyrites. Treatment of BaSO^ with HP and igniting, caused a loss, due, appar- ently to the formation of BaF,. If but little H^SO^ was added together with the HF, some loss, though not so much, was experienced; with larger quantities of H^SO^* decomposition of the kind could be entirely prevented, and no loss was sustained. Nitrates in Potable Waters, Gill {/, Am, Chem, Soc, xvi., 193) gives a series of comparative results made between the aluminum method and the phenol sulphuric method. The latter is shown to be the most delicate, and yields more accurate results ; the aluminum process giving, on the whole, lower results than the phenol sulphuric. Other reduction methods are also regarded as less delicate or satisfactory. BOOK REVIEWS. Thbrmodynamtcs of Reversible Cycles in Gases and Saturated Vapors. By M. I. Pupin, Ph.D.; John Wiley & Sons. 1894. This is a pleasant little volume of 112 pages, containing a full syn- opsis of a ten weeks' undergraduate course of lectures delivered by Dr. Pupin, arranged and edited by Max Osterberg, student in electrical en- gineering, Columbia College. It retains the piquancy of lectures not intended for the press, and presents the elements of the science with clearness and vigor. J. W. D. Plane Trigonometry. By S. L. Loney, M.A., late Fellow of Sidney Sussex Col- lege, Cambridge, Professor at the Royal Holloway College; University Press, Cambridge. New York : Macmillan & Co. 1893. Preceding ihi text proper come several pages of the principal formu- lae listed together for ready reference. The work is divided into two parts, Geomeirical and AnalyticaL In the former the exposition of systems of angular measurement, nature of trigonometric functions, their periodicity, inter-relations, and particular values, is exceedingly plain and thorough. Typography is made a fac- tor in the numerous suggestive tabular statements ; diagrams are not spared, and well- devised problems enforce each principle. Logarithms are introduced after the deduction of the formulae for sums, differences, multiples, and submultiples of angles. Then follow the applications to triangles, and to the solution of many interesting propositions. Part II, opens with the development of exponential and logarithmic series, and then proceeds to the discussion of complex quantities.^ {x-^ yV — i), with their application to expansions, evolutions, and the production of important theorems relating to circular and hyperbolic functions, and common numbers. A striking feature of the work is the lucidity of the demonstrations. To the instructor who would review in an easy way, as well as to the student who would acquaint himself with the elements and a rather ex- tensive scope of the applications of plane trigonometry, Mr. Loney's treatise will prove very serviceable. J. W. D. The Ore-Deposits of the United States. By James F. Kemp, A.B., E.M. Professor of Geology in the School of Mines, Columbia College. New York : Scientific Publishing Company. 1893. Large 8vo., xvi. and 302 pp., 67 cuts. Price,$4.
Professor Kemp, in his preface, says that his book has a two-fold pur-
pose ; first, to supply a condensed account of the metalliferous resources
of the country, for a text-book and book of reference; and second, to
give an extended view of the whole field, to show what has been done,
and thus to stimulate further investigation and study of the puzzling
questions of origin and formation of metalliferous deposits.
There can be no doubt that Professor Kemp has succeeded admirably
in the objects he had in view. He has given us a most satisfactory con-
densation of the very voluminous literature relating to the ore-deposits
of this country ; the book is clearly written, and well arranged for study
BOOK REVIEWS. 283
and reference, and the text is everywhere supplemented by abundant
references to original sources of information.
The book is divided into two parts. Part I. occupying about one-
quarter of the volume, is introductory and theoretical. Part II. contains
descriptions of typical ore-deposits of the different metals. Part I. con- ^
tains the following chapters: I. Geology and topography of the United
States. II. Formation of cavities. III. Vein minerals and their source.
IV, Filling of veins. V. Characteristics of Veins. VI. Classification
of ore-deposits.
In the chapter on the filling of veins, Professor Kemp states fairly
and judicially the evidence for lateral secretion, and in support of infil-
tration from below. He shows clearly that the weight of evidence is in
favor of the latter and more generally accepted theory, but suggests as
well a common gronnd on which the advocates of each theory may
meet.
In the chapter on classification the author gives the schemes proposed
by various writers on the subject in modern times, and shows that the
earlier attempts were based wholly on shape and form, and that as the
knowledge of the origin and methods of formation increased, schemes
based partly on form and partly on origin were adopted. He gives
credit to the reviewer for a scheme of classification based entirely on
place and method of deposition, adopted a number of years ago as a
basis for lectures on the irregularities of mineral deposits introductory
to the course on mining. As these irregularities are largely due to the
method of formation, a genetic system of classification seemed to be
necessary for their proper and logical discussion. In like manner a
treatise on ore-deposits concerns itself largely with questions of origin,
and thus a genetic system would seem to be both rational and useful.
Acting on this idea. Professor Kemp has developed an elaborate sys-
tem of classification for metalliferous deposits. This was first published
in the School of Mines Quarterly for November, 1892, and now ap-
pears in a somewhat modified form. Ore-depjsils are divided into three
groups: I. Of igneous origin ; II. Deposited from solution; and III.
Deposited from suspension. In the first class, of igneous origin, the
author places only a few iron-ore deposits, constituting excessively basic
developments of fused and cooling magma. The third class are sec-
ondary deposits due to erosion or weathering of mineral-bearing rocks.
The great bulk of ore-deposits fall into the second class. This class,
deposits from solutions, is subdivided into eleven groui>s. The first
group, surface precipitations, is again subdivided according to the
method of precipitation. The other ten groups are all underground
deposits. It seems to us that here the author has introduced an unnec-
cessary number of subdivisions, and that his classification would be much
improved by judicious combination of some of these groups. For exam-
ple, he recognizes in his groups many different kinds of cracks, fissures
and cavities, viz., extended fissures, shear zones, cracks at bends in strata,
joints caused by cooling or drying, cracks in collapsed beds due to solu-
tion of underl ing rocks or to dolomitization, chambers in limestone,
volcanic necks. Groups of this sort might be multiplied almost indefi-
nitely. It is questionable whether such minute classification serves any
useful purpose, and whether it does not, on the other hand, tend to ob-
scurity rather than to a clear recognition of salient lines of division.
284 7»^ QUARTERLY,
The mere place of deposition does not seem to be of sufficient impor-
tance to be thus magnified. The place of deposition, in the case of
these subterranean deposits, is simply the channel through which the de-
positing solution has passed on its way to the surface. It is conceivable
that the same deposit may at different parts of its comse be found in
all the different kinds of cracks, fissures and cavities above enumerated,
and may belong at the same time to each and all of the different groups.
Part I. concludes with a bibliography of modern works and papers
on ore-deposits, which will be useful to students of this subject.
Part II. is divided into the following chapters: I. Iron ores, limonite,
siderite. II. Hematites, red and specular. III. Magnetite and pyrite.
IV. Copper. V. Lead, alone. VI. Lead and zinc. VII. Zinc, alone
or with metals other than lead. VIII. Lead and silver. IX. Silver and
Gold. In each chapter the examples given are arranged more or less geo-
graphically and according to nnining regions. The examples of ore-
deposits are numbered consecutively throughout the book, and deposits
of a similar origin and character are grouped under a single nuftiber.
Thus, example i6, the beds (veins) of pyrite, often lenticular, of the Ap-
palachian region appears first at the end of the chapter on iron, on page
131. Next, example i6d5, Ore Knob, N. C, and 16/^, Spenceville, Cal.,
copper pyrite deposits, appear in the chapter on copper, pages 135 and
136. Examples 16^ and idd appear under nickel, pages 269 and
270. For the benefit of those who may wish to study certam groups of
ore-deposits, without regard to their location or their mineral contents,
a supplementary index of examples would prove serviceable and should
be inserted in subsequent editions. This lack is only imperfectly sup-
The descriptions of individual deposits are clear and satisfactory, even
though necessarily much condensed, and the opinions of the different
authorities as to origin and manner of occurrence are most admirably
summed up. This condensation of such a mass of material must have
cost the author much labor. It would have been less work to have com-
piled an encyclopaedia, in several volumes, describing the same deposits,
and such a monumental work would have made a greater impression on
the average reader than the present modest volume. The student, the
investigator and the man of affairs who have occasion to consult th6
book will, however, appreciate highly this feature In each case the de-
scription is supplemented by copious references to the original papers,
so that the student can obtain such further details as he may need. The
author states that every effort has been taken to make the bibliography
complete. H. S. M.
WOODBRIDGE SCHOOL,
FORMERLY
School of Mines Preparatory School,
Between 48th and 49th Sts., NEW YORK CITY.
A HIGH SCHOOL,
INTRODUCTORY TO ALL COLLEGES.
J. WOODBRIDGE DAVIS, C.E., Ph.D,
I? E.I2<TO I :P-Al L-
Twelfth Year Begins October 2, i8gj.
Four hundred Students of Columbia School of Mines have been
instructed in the Woodbridge School.
Also a large number have been prepared for Massachusetts Institute
of Technology, Stevens Institute, Sheffield Scientific School, Troy
Polytechnic Institute, Cornell University, and the Classical, Medical
and Law Departments of Harvard, Yale, Columbia and Princeton.
Vol. XV. No. 4. JULY, 1894.
THE
SCHOOL OF MINES
QUARTERLY.
A
JOURMAI. OF APPI^IBD SCIKKCK.
I mmw
BOABD OF EDITOBS.
A. J. MOSES, Adj. Prof, of Mineraloi^y. £. WALLER, Analytical Chemist.
J. F. KBMP, Prof, of Geology. J. L. GREENLEAF, Adj. Prof. Civil Engineer'^.
R. PBBLE:, Jr., Adj. Prof. Mining. JOS. STRUTHERS, Tutor in Metallurgy.
ManafiTlngr Editor, A. J. MOSES.
CONTENTS:
The Optical Recognition and Economic Importance of the Common
Minerals Found in Building Stones. By Lea McI. Luquer 285
Fire Assay for Lead. By Malvern W. lies 336
Project for Utilizing Bassasseachic Falls. By Edward D. Self. 345
On the Occurrence of Cretaceous Clays at Northport, L. 1. By
Heinrich Ries 354
The Kosaka Mining and Reduction Works, Ricchoo, Japan. By M.
Kuwabara, Osaka, Japan 355
Abstracts 375
Book Reviews 381
COLUMBIA COLLEGE.
NEW YORK CITY.
Registered at the New York Post Office as Second Class Matter.
T^VO DOLLARS PER YEAR. FIFTY CENTS PER NUMBER.
All Remittancca should be made payable to Order of "The School of Mines Quarterly.*'
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MANUFACTURERS OF
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We make
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THE
SCHOOL OF MINES
QUARTERLY.
Vr,L. XV.. JULY, 1894. No. 4.
THE OPTICAL RECOGNITION AND ECONOMIC
IMPORTANCE OF THE COMMON MIN-
ERALS FOUND IN BUILDING
STONES.
By lea McI. LUQUER.
Introduction.
As the scope of this work is necessarily limited, it will be im-
possible to take up in detail the nomenclature, geological forma-
tion, chemical and physical structure, mineralogical composition,
and causes of deterioration of building stones. Special attention,
however, will be called to the facts that can be observed by a care-
ful microscopic examination of thin sections of building stones.
This kind of investigation was first recommended by Cordier, in
1 8 16, but at that time neither chemical nor optical methods were
sufficiently developed to make it practicable. H. C. Sorby was
one of the first to successfully apply the microscope to the study
of lithology.
The great importance of this method is clearly set forth by
Spencer F. Baird in an article on the study of thin rock sections :
" This method of study in the hands of the microscopic lithologist
has been most fruitful in developing valuable and interesting knowl-
edge of a scientific character. By its means the nature and com-
position of almost all of the commonly occurring rocks have been
determined, and exactly those same features which are of import-
ance in scientific study are the ones which determine the value and
VOL. XV. — 20
286 THE QUARTERLY.
appearance of building stones, and there is no distinction between
the scientific and the practical." *
The facts that can be determined by a microscopic examination
may be divided into two classes, mineralogical and physical or
structural :
1°. Mineralogical: {a) The Component Minerals. — Although a
large number of minerals have been found in building stones, those
that are essential and of economic importance are few in num-
ber, rarely exceeding three or four in any one kind of rock. It is
well to remember, however, that minerals present even in minute
quantities may be of great economic importance.
{p) The Chemical Composition of these Minerals. — Much may be
learned regarding this by an optical examination. Many of the
ferruginous varieties of certain mineral species have stronger pleo-
chroism, etc., than those containing less iron, and, as the ferrugi-
nous varieties are more liable to decomposition, this fact is im-
portant.
[c] The Condition of these Minerals, — As to whether they are fresh
or weathered, or contain many cleavage cracks, fractures, and in-
clusions.
2°. Physical or Structural : (a) The dense or porous nature
of the rock, (b) The kind of cohesion existing between the com-
ponent minerals, (c) The homogeneity of the distribution of these
minerals.
The structure of the stone and the state of the component min-
erals are very important facts for consideration, as the greatest
cause of disintegration in our climate may be said to be due to
extreme changes of temperature, action of frost, etc. According
to Prof Geikie, the action of frost is equivalent to the pressure of
138 tons per square foot. Water may " freeze out" of a coarsely
porous stone, while in a compact stone it may do much damage.
" Other things being equal, the value of a building stone may be
said to be inversely as its porosity."
An elementary knowledge of optics, including the use of the
lithological microscope, is needed for the recognition of the
common rock-forming minerals by the characters given in the fol-
lowing tables.
For those who lack this knowledge, the author refers to the
* Building Stone Collection, U. S. Nat. Mus., No, 9.
MINERALS IN BUILDING STONES. 287
following works: Atkinson's Ganot's /y/;'^/^^ (for optics) ; Iddings'
translation of Rosenbusch's Mikroskopische Physiographic der pet-
rographisch wichtigen Mineralien; E. S. Dana's Text- Book of Min-
eralogy , and the article on " Building Stones " in the Tenth United
States Census (for principles of optical mineralogy and description
and use of instruments); Rutley on Rocks and Methods of
Modern Petrography by H. Hensoldt and L. McI. Luquer, in
School of Mines Quarterly, Vol. X., p. 212; Vol. XL, p. 29;
Vol. XII., p. 132; and Vol. XIII., p. 357 (for the preparation and
mounting of sections).
The order of arrangement of the mineral species is, in general,
that adopted by Rosenbusch in his Mikroskopische Physiographie
der petrographisch wichtigen Mineralien ; but, in some cases, for
convenience in study and reference, changes have been made, as,
for example, the two iron sulphides, marcasite and pyrrhotite, are
placed immediately after pyrite.
Synopsis of Order of Minerals :
Isotropic: Isometric.
Anisotropic: C/«/^;«^/— Tetragonal and hexagonal. Biaxial —
Orthorhombic, monoclinic, and triclinic.
Aggregates.
The group classification is used for the feldspars, micas, and
chlorites, as in some cases it is almost impossible to differentiate,
by the microscope alone, between similar members of a group, and
in many cases this is not economically important.
Nearly all the rock-forming minerals become transparent in thin
sections, but when opaque, attention is called to the fact, and the
examination is made by incident light. The optical characters of
the minerals are recorded in the order they would be observed in
the course of an examination with the lithological microscope.
With transmitted light are noticed phenomena of structure,
color, relief, cleavage, inclusions, etc. With parallel polarized
light, the polarizer or lower nicol being in position, pleochroism
may be noticed on revolving the stage. With the analyzer or
upper nicol also in position (crossed nicols) phenomena of polari-
zation colors, extinction, etc., are observed ; and by rotating the
stage, extinction angles can be measured. In a few cases the
results of observation with convergent polarized light are given,
but generally this method of observation is not practicable, and
288 THE QUARTERLY,
therefore the reader is referred to the very detailed description
of all the optical properties of minerals found in Rosenbusch*s
Mikroskopische Physiographie der petrographisch wichtigen Min-
eralien (Iddings* translation).
An effort has been made to make this work as simple as possible,
because, when a mineral cannot be recognized by the following
tests, the difficulties of determination are very much increased,
and can only be attempted by an expert petrographer.
Under the head of artificial alteration is stated the action of
acids, which may be important to consider in certain localities
where the atmosphere is contaminated by acid fumes. To show
the effect of organic acids, acting through long periods of time, on
the minerals composing building stones, the results of Dr. Bolton's
experiments with citric acid are given in the appendix. These
results are not incorporated in the tables, because, in some cases,
the action has been allowed to continue for two years, and it is
quite probable that minerals which are now regarded as insoluble
in certain acids would be effected in a similar way if exposed for
an equal length of time.
As a matter of convenience, the important diagnostic properties
are grouped together ; and for a like reason, prominence is given
to the method of differentiating similar minerals.
It is hoped that with proper preliminary knowledge the appli-
cation of the facts here recorded may be useful to architects, civil
engineers and builders.
In addition to the microscopic investigation of any building
stone proposed for use, it is, of course, expected that the other
general facts regarding cost, transportation, artistic effect, weather-
ing properties, crushing strength, etc., should be considered.
In closing, the author wishes to express his grateful apprecia-
tion of the valuable advice and assistance given in the preparation
of this work by Dr. Thomas Egleston, Professor of M neralogy
and Metallurgy; Dr. J^ F. Kemp, Professor of Geology; and Dr.
A. J. Moses, Adj. Professor of Mineralogy.
PYRITE, Pyrites.
Isometric.
Composition : FeSg. H., 6 to 6.5. Sp. gr., 4.9 to 5.2.
Usual Appearance in Sections : Crystallized in cubes, pen-
MINERALS IN BUILDING STONES. 289
tagonal dodecahedrons, or combinations of these forms. Some-
times in irregular grains. Outline of cross-section generally square.
Opaque, and by incident light bright yellow, with strong
metallic lustre.
Alteration :
Artificial. — Soluble in nitric acid, but not noticeably acted on by
hydrochloric acid.
Natural {7veathering), — Alters very easily to the oxides of iron
(rust).
General Occurrence in Building Stones : May be present in
all kinds of rocks. Found in granite, syenite, gneiss, schists,
sandstone, limestone, serpentines, clays and slates. Its presence
can often be detected by dark grayish black streak while grinding
section.
Marcasite.
The same in composition as pyrite, but more easily decomposed,
and, therefore, more injurious in building stones. Distinguished
from pyrite by absence of square cross-sections,
Pyrrhotite.
I Composition: Fe^S^ to Fe,iSi2. Distinguished from pyrite by
being practically always in irregular masses and not in crystals,
and by bronze yellow color in incident light.
Economic Effect of the Sulphides of Iron in Building
Stones : The presence of pyrite, etc., is generally considered det-
rimental in stone ; but its liability to decomposition and the re-
sulting injurious effects depend on the nature of the pyrite and the
structure and character of the stone. Sharp, well defined pyrite
i crystals are hard to decompose, and may remain unaffected in
stone if it is non-absorbant, compact and composed of unweathered
minerals. On the contrary, the presence of pyrite is very injurious
in porous, decomposed stone, as its alteration commonly causes
unsightly rust stains. The oxidation of the sulphide of iron into
sulphate is also accompanied by an increase in volume, which adds
the mechanical effect of expansion to help in disintegrating the
stone.
Sandstone. — The sulphides may decompose and disintegrate the
stone, but, unless present in large amounts, the only danger may
be the staining or discoloration of the stone. If pyrite is evenly
290 THE QUARTERLY.
distributed in small particles through the sandstone it may even
do good by supplying a new cementing material.*
Limestone. — The presence of pyrite, and especially marcasite,
is generally very injurious. In the process of weathering the car-
bonates of lime and magnesia are decomposed by the sulphuric
acid, resulting from the pyrite, and sulphates are formed with set-
ting free of carbon dioxide. Magnesium sulphate is a soluble,
efflorescent salt, while calcium sulphate is insoluble. Therefore,
a magnesium or dolomitic limestone may be more affected than a
pure calcium limestone.
MAGNETITE, Magnetic Iron Ore.
Isometric.
Composition : Fe304. H., 5.5 to 6.5. Sp. gr., 4.9 to 5.2.
Usual Appearance in Sections : Grains, crystals (generally
octahedra) and massive
Twinning, — Common, according to Spinel law.
Opaque, and by incident light, bluish-black, with strong metallic
lustre. Strongly magnetic.
Alteration : Soluble in hydrochloric acid, and when altered
becomes coated with earthy limonite.
Differentiation: From Hematite, Chromite, Ilmenite and
Graphite by being easily separated from powdered rock by weak
magnet.
Usual Associates in Sections : In the eruptive rocks belongs
to the oldest secretions from the magma, immediately followed by
chrysolite, biotite, hornblende, augite, etc., and often appears as
inclusions in these and other minerals.
General Occurrence in Building Stones: Very widely dis-
tributed in crystalline schists and eruptive rocks. May be present
in granite, in minute crystals, but not common in muscovite
granite ; also in syenite and slates.
Economic Effect in Building Stones : When present in large
amounts it may become entirely changed into the sesquioxide of
iron (rust). The rock becomes then stained a rusty red color, as
seen in many diabases.
* Prof. Winchell, Geol. of Minn., Vol. I., p. 189.
MINERALS IN BUILDING STONES. 291
CHROMITE.
Isometric.
Composition: FeCr304. H., 5.5. Sp. gn, 4,3 to 4.6.
Usual^ Appearance in Sections: Octahedral crystals, like
magnetite, and grains.
Differentiation : From Magnetite. By having weak metallic
lustre and grayish-black to black color. It is sometimes trans-
parent in very thin sections, when it has no metallic lustre and its
color (by transmitted light) is brown to reddish-brown, with a
very rough surface due to the high index of refraction. It is non-
magnetic, gives chromium bead test and is often surrounded by a
green halo of chrome ochre.
Alteration : Not acted on by acids.
General Occurrence in Building Stones : Common in crys-
talline rocks, rich in magnesium, and in serpentine.
LIMONITE.
Amorphous.
Composition : Fe2(OH)j, Fe^Og, frequently quite impure.
H., 5 to 5.5. Sp. gr., 3.6 to 4.
Usual Appearance and Characters in Sections : A yellow-
ish brown, non-metallic, earthy substance, which being amorphous
is isotropic. It is essentially a decomposition product, and is often
found forming a halo around magnetite. It is soluble in hydro-
chloric acid.
General Occurrence in Building Stones, and Economic Ef-
fect : May be present wherever there has been decomposition of
the iron ores or ferruginous minerals, and for this reason is usually
a sign of weakness in the stone.
GARNET.
Isotropic. Isometric.
Composition : R"s R^'j (SiOJg, R'' is Ca, Mg, Fe or Mn ; R'" is
Al, Fe'", or Cr, rarely Ti. H., 6.5 to 7.5. Sp. gr., 3.15 to 4.3.
Usual Appearance in Sections : Irregular grains, somewhat
292 THE QUARTERLY.
resembling spots of gum ; also in aggregates or simple crystals,
showing forms ocO(i lo), and 202(21 1), alone or in combination.
Parallel Polarized Light:
Color. — Colorless or nearly so, to red.
Index of Refraction. — n^a = 1.7468 — 1.8141.
Relief. — High, and rough surface.
Fracture. — Irregular cracks occur, due to great brittleness of
mineral ; but no cleavage is noticed.
PUochroism. — None.
Parallel Polarized Light, Crossed Nicols : As it is iso-
tropic, sections remain dark during complete rotation. Optical
anomalies may however occur.
Alteration :
Artificial, — Practically insoluble in hydrochloric acid.
Natural (weathering). — Usually fresh, but may be found altered
to chloritic matter.
Important Diagnostic Properties : General reddish color. —
High relief and rough surface. — Irregular cracks, and absence of
cleavage. — Isotropic character.
Usual Associates in Sections: Quartz, orthoclase, biotite, and
hornblende.
General Occurrence in Building Stones : Most plentiful in
metamorphic rocks ; as accessory in granite, gneiss, schists, crys-
talline limestone, serpentine, slate, etc. ; as characterizing constit-
uent of the garnet rock or marble of Morelos, Mexico. This rock
is composed of pink garnet, yellowish brown vesuvianite and lime-
stone. It is cut and used for ornamental slabs, etc.
Economic Effect in Building Stones : Detrimental in stones
designed for finely polished work. Garnets are hard and brittle,
and are apt to break or chip out from the stone during process of
dressing and polishing.
RUTILE.
Anisotropic. Uniaxial. Tetragonal.
Composition : TiOg. H., 6 to 6.5. Sp. gr., 4.15 to 4.25.
Usual Appearance in Sections : In grains, when the individ-
uals are large, but in sharp, prismatic crystals when microscopic.
MINERALS IN BUILDING STONES. 293
Twinning. — Very common. The very small individuals of rutile
may form net-shaped groups, called sagenitey the crystals crossing
one another at angles of 60^.
Parallel Polarized Light:
Color, — Yellow to reddish^brown.
Index of Refraction, — oi^^ = 2.6158. ^n* = 2.9029 (Barwald).
Relief, — Very strong, and very rough surface.
Cleavage. — Very perfect, parallel to the prism oc P ( 1 10), appears
as fine straight cracks. May also have imperfect cleavage parallel
to the second order prism oc P x) (100).
Pleochroism, — Not especially noticeable.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Very strong.
Polarization Colors. — Of minute needles, very brilliant. If the
section is thick, the polarization colors are indistinct and of the
higher orders, and therefore not noticeable when the rutile is
strongly colored.
Extinction, — Rutile is uniaxial, but basal sections only remain
dark during rotation of stage, when twinning is absent. The ex-
tinction in all other sections is symmetrical, being parallel and at
right angles to the longitudinal axis.
Alteration :
Artificial, — Insoluble in hydrochloric acid.
Natural (weathering). — Alters to a white or yellowish, fibrous or
granular substance, strongly refracting, and similar to the alteration
product of ilmenite.
Important Diagnostic Properties : Twinned structure. — Yel-
lowish to reddish-brown color. — Very high relief and rough sur-
face. — Brilliant polarization colors in minute crystals, and general
absence of polarization colors in large crystals. — Symmetrical ex-
tinction.
Differentiation : From Zircon. — See under Zircon.
Usual Associates in Sections : Quartz, orthoclose, horn-
blende, augite, garnet, etc.
General Occurrence in Building Stones : May be either pri-
mary or secondary ; and may be found in gneiss, crystalline schists
(especially those rich in hornblende and augite), slates, etc.
294 THE QUARTERLY.
ZIRCON.
Anistropic. Uniaxial. Tetragonal.
Composition: ZrSiO^. H., 7.5. Sp. gr., 4.68 to 4.70.
Usual Appearance in Sections : In short prismatic crystals,
never massive.
Parallel Polarized Light :
Color. — Generally colorless or light yellow.
Index of Refraction. — u> = 1.960 ; e = 2.015 (Brewster).
Re/iff. — High, and rough surface.
Pleochroism. — Not noticeable.
Parallel Polarized Light, Crossed Nicols ;
Double Refraction. — Very strong.
Polarization Colors. — Very brilliant even in minute crystals.
Extinction. — As zircon is uniaxial, basal sections remain dark
during rotation of stage. In all other sections the extinction is
symmetrical, being parallel and at right angles to the longitudinal
axis.
Convergent Polarized Light : Basal sections show several
rings in addition to dark cross, and the optical character is +.
Alteration : Not attacked by acids, and very rarely altered.
Important Diagnostic Properties: Generally in short pris-
matic crystals. — Strong relief and rough surface. — Brilliant polari-
zation colors. — Symmetrical extinction.
Differentiation :
(a) From Rutile. — By absence of test for titanium on isolated
crystals, and by absence of cleavage and twinned structure.
{U) From Titanite. — By absence of cleavage and the acutely
rhombic sections, so common in titanite.
Usual Associates in Sections : Quartz, orthoclase, plagio-
clase, biotite, hornblende, augite, etc.
It is one of the oldest constituents of the rocks in which it
occurs, and hence may often be found as inclusions in other min-
erals.
General Occurrence in Building Stones ; Found in granite
and syenite as an accessory mineral, especially abundant in
Gloucester granite ; and may also occur in gneiss, diorite, gabbro,
schists, limestone, etc.
MINERALS IN BUILDING STONES. 295
GRAPHITE.
Hexagonal.
Composition: C. H. i to 2 ; Sp. gr., 2.09 to 2.23.
Usual Appearance in Section : In minute particles, or in
flakes and grains of irregular shape, seldom crystallized.
Opaque, and by incident light black with metallic lustre. Not
acted on by acids.
General Occurrence in Building Stone: In granite, gneiss,
crystalline schists, limestone, etc.
HEMATITE.
Hexagonal. •
Composition : Fe203. H., 5.5 to 6.5. Sp. gr., 4.9 to 5.3.
Usual Appearance and Characters in Sections : Occurs in
irregular flecks and scales, earthy or granular. Distinct crystal-
line forms are not often observed in rocks. It is opaque and, by
incident light, black with tinge of red and metallic lustre, or red,
especially when earthy or granular. It may also be transparent
with red tints. No pleochroism is observed. It is soluble in
hydrochloric acid.
General Occurrence in Building Stones and Economic
Effect : Found in granite, syenite, crystalline schists, etc. Very
often as inclusions in minerals, giving them a reddish color, as in
the quartz, feldspar and mica of granites.
In the amorphous form it is often the cementing material of the
red or brownish-red sandstones.
ILMENITE, Menaccanite.
Hexagonal.
Composition : FeTiOj to n FeTiOg + nt FejOg. H., 5 to 6.
Sp. gr., 4.5 to 5.0.
Usual Appearance in Sections : Irregular masses without
crystallographic outline.
Opaque, and by incident light iron black with brownish tinge and
metallic lustre.
296 THE QUARTERLY.
Alteration :
Artificial, — Attacked slowly by hot hydrochloric acid, solution
when heated with tin becomes violet.
Natural {feathering). — Alters to a whitish, strongly refracting
substance, only slightly transparent. Its structure is sometimes
granular, sometimes fibrous. This alteration product often devel-
ops along definite crystallographic directions.
Differentiation : From Magnetite. — By occurring in irregular
masses, and by whitish, strongly refracting decomposition product.
Magnetite being in crystals or grains, and having a brownish de
composition product.
Usual Associates in Sections : Plagioclase, augite, horn-
blende, chrysolite, magnetite, etc.
General Occurrence in Building Stone : It belongs to the
oldest secretions from the magma, and its distribution in rocks is
very great. It is found in granite, syenite, gneiss, diabase, diorite,
gabbro, crystalline schists, etc.
QUARTZ.
Anistropic. Uniaxial. Hexagonal.
Composition : SiOj. H., 7. Sp. gr., 2.60 to 2.66.
Usual Appearance in Sections : Massive or in grains, and as
it was apparently the last mineral to form in crystallized rocks, its
outline is determined by the other component minerals. Very
rarely crystallized in rocks.
Parallel Polarized Light:
Color, — Colorless, although by incident light it may appear col-
ored or cloudy, if it contains many inclusions.
Index of Refraction. — **>ri%=^ i. 54418; ^na = 1-55328 (Rudberg).
Relief. — None, and plain surface.
Cleavage. — Rarely noticed.
Ificlusions, — Liquid, gas and solid.
Pleochroism.— None.
Parallel Polarized Lights, Crossed Nicols :
Double Refraction, — Weak.
Polarization Colors, — Bright but weak in very thin sections, only
blue gray, etc.
MINERALS IN BUILDING STONES. 297
ExHfiction. — As quartz is uniaxial, basal sections remain dark
during a complete rotation of stage. In all other sections extinc-
tion takes place, but due to the absence of cleavage and crystallo-
graphic outlines no extinction-angles can be obtained. Thin sec-
tions do not show circular polarization.
Convergent Polarized Light: Basal sections show a dark
cross, without any rings, and the optical character is +.
Alteration :
Artificial. — Not attacked by ordinary acids.
Natural ( Weathering). — Always appears fresh and unweathered
in sections.
. Important Diagnostic Properties: Colorless. — Absence of
cleavage and pleochroism. — Low relief and not very brilliant po-
larization colors. — Dark cross without rings, and + optical char-
acter in convergent light. — Fresh, unweathered appearance.
Differentiation :
{a) From Santdine when in grains. — By use of convergent light
on sections which appear isotropic.
{b) From Nephelite and Apatite. — By absence of hexagonal
crystals.
{c) From Calcite. — By absence of cleavage and twinning, and
by no effervescence with acids.
Usual Associates in Sections : Orthoclase, more rarely plagio-
clase, mica, hornblende and augite.
General Occurrence in Building Stones : Found in granite,
gneiss, crystalline schists, sandstone, quartzite, etc., and in small
amounts in limestones and slates.
Economic Effect in Building Stones.
Granite. — Essential constituent, together with feldspar and
mica.
Quartz is brittle, has a constant hardness, and does not deter-
mine the hardness or ease of working of granite. Stones like
granite, however, which are rich in quartz, work more easily and
crush sooner than the trap-rocks, which contain no quartz.
Granitic quartz often contains, a large number of pores partially
filled with fluids. It is well to consider the number and size of
these pores, as they may tend to explode when subjected to high
heat, and thus affect the durability of the stone.*
* This view does not seem to be sustained by an examination, made by G. P. Mer-
298 THE QUARTERLY.
The source of the blue color of the quartz in some granites is
not known.
Sandstone. — Principal constituent together with many other
accessory fragments of the rock-forming minerals.
Sandstones may be divided into siliceous, calcareous, ferrugi-
nous and argillaceous varieties, depending on the character of the
cementing material.
The siliceous sandstone is the most durable, especially if it has
been metamorphosed into a quartzite ; but at the same time it is
very hard to work and light in color.
The calcareous sandstone is not safe to use when subjected to
the action of acid waters or vapors, especially in crowded citi^
where there is an excess of COj in the air, but can be worked very
easily.
The ferruginous sandstone is generally the best (unless the iron
has come from decomposing pyrite), as it is not so hard to work
as the siliceous and not so easily weathered as the calcareous
sandstone ; also, the brown or reddish color of this variety is
attractive.
The argillaceous sandstone is the most objectionable, as the
clayey cement absorbs water easily and tends to disintegrate the
stone.
The structure also affects the durability, sharp grains of pure
quartz, with little cementing material, making a much more dura-
ble sandstone than one composed of rounded grains mixed with
fragments of other minerals, which may be more or less decom-
posed. The more porous sandstones may be said to be the less
durable.
The accessory mineral fragments present often give special char-
acter to the sandstone. Kaolinized feldspar, mica, pyrite, marca-
site, calcite in quantity, and clay, when present, are injurious, as
they are all liable to decomposition. The quartz in sandstone may
contain cavities and bubbles as well as the granitic quartz.
A microscopic examination may enable the observer to deter-
mine whether the decomposition of the accessory mineral grains
has taken place before or subsequent to the ** make up " of the
rill, of a large number of sections of granite used for buildings in this country. See
G. P. Merrill, The Collection of Building and Ornamental Stones in the U, S. Nat.
Museum : A Handbook and Catalogue^ p. 341, Washington, 1 889.
MINERALS IN BUILDING STONES. 299
sandstone ; and thus, in connection with the structure of the rock,
to judge as to its probable durability.*
Limestone. — May be present as an impurity. The silicious and
compact limestones are better for construction purposes than the
argillaceous or ferruginous limestones.
CALCITE.
Anisotropic. Uniaxial, Hexagonal.
Composition : CaCO^. Ca may be replaced by small quantities
of Mg, Fe, Mn, etc. H., 3 or less. Sp. gr., 2.71 to 2.72.
Usual Appearance in Sections : In grains and aggregates.
May be fibrous or oolitic. Never in crystals in rocks.
Tivinning. — Generally shows polysynthetic twinning parallel to
— ^ R 'r(oii2), which is very common in the crystalline lime-
stones, and may have been produced by pressure. The twinning
shows itself between crossed nicols as a series of light and dark
bands.
Parallel Polarized Light:
Color. — Colorless when pure, but may appear colored by trans-
mitted light, due to organic pigments.
Index of Refraction. — m^^ = 1.6585, e^. = 1.4864.
Relief, — Low, and plain surface.
Cleavage. — Parallel to the rhombohedron R ^ (loii) appears in
thin sections as many sharp cracks, whose angles of intersection
depend on the position of the section.
Inclusions. — Fluid inclusions frequent.
Pleockroism, — None.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Very strong. Can be noticed with analyzer
alone.
Polarisation Colors. — High, even for very thin sections, being
clear white or pale green. The brighter colors of the lower orders
are wanting.
Extinction. — As calcite is uniaxial, basal sections remain dark
during rotation. In all other sections extinction takes place, and
* Thomas Egleston, Ph.D , ** The Cause and Prevention of the Decay of Building
Stones," Trans. Am. Soc. C, E., Vol. XV., 1886.
300 THE QUARTERLY.
in general the direction of extinction is not parallel to any outline,
but is symmetrical to the cleavage cracks when they appear.
Convergent Polarized Light : Basal sections, even when very
thin, give interference cross and several colored rings, and optical
character is — .
Alteration : Very easily attacked and completely dissolved
with effervescence by cold dilute acids, including carbonic.
Important Diagnostic Properties : Not in crystals. — Poly-
synthetic twinning. — Cleavage parallel to rhombohedron. — Very
strong double refraction, giving polarization colors of a high order
(white or very faint green). — Effervescence with cold dilute acids.
Differentiation :
{a) From other Isomorphous Carbonates. — By ease with which
it is attacked by cold dilute acids, test can be made on slide after
removing coveh
(^) From Magnesium- BEARING Calcite. — Use micro-chemical
tests.*
Usual Associates in Sections: In nearly all rocks bearing
augite, hornblende, biotite, and plagioclase.
General Occurrence in Building Stones : Distribution very
great, in addition to great sedimentary limestone deposits. It is
very often a secondary product, and may be found in granite,
syenite, gneiss, diabase, diorite, basalts, serpentine, clays and
slates.
DOLOMITE.
Anisotropic. Uniaxial. Hexagonal.
Composition : (CaMg)C03, when pure CaO =: 30.4, MgO =
21.7, C02 = 47.8. Proportions of Mg and Ca vary, and Fe and
Mn also occur. H., 3.5 to 4. Sp. gr., 2.8 to 2.9.
Usual Appearance in Sections : In rocks chiefly as crystals,
even dense homogeneous aggregates show tendency towards crys-
talline boundaries (saccharoidal structure). Crystals almost always
unit rhombohedron R t^ (ioii), with tendency to curved surfaces.
Also in grains.
* Microscopical Physiography of Rock- Making Minerals^ Rosenbusch, Iddings*
translation, p. 112.
MINERALS IN BUILDING STONES. 301
Its behavior, under the microscope, is similar to that of calcite.
Alteration : Only slightly attacked by cold dilute acids, in-
cluding carbonic, but if acid is heated it dissolves easily with
effervescence.
Important Diagnostic Properties : Crystals or crystalline. —
Rhombohedral cleavage. — Very strong double refraction, giving
polarization colors of a high order (white or very faint green, etc.).
Differentiation : From Calcite. — Not easily attacked by cold
dilute hydrochloric acid, unless mixed with calcite. Test can be
made on slide with cover off. By absence of polysynthetic twin-
ning, which is present in calcite, and by crystallized or crystalline
condition.
General Occurrence in Building Stones : As an independent
rock and as crystals in limestone, may also occur in slates.
Economic Effect of Calcite and Dolomite in Building
Stone :
Sandstone. — Calcite may be present as cementing material,
and is injurious on account of its easy solubility in acid waters,
thus rendering the sandstone porous and more liable to decompo-
sition. Calcite may also be present as product of kaolinization of
feldspars.*
Marbles, Limestones, Etc. — Essential constituents. The dif-
ferent kinds of limestones may be classed as silicious, argillaceous,
ferruginous, magnesian and dolomitic.
They vary greatly in texture, strength and durability, some
being stronger than many granites in crushing strength and, under
certain conditions, equally enduring. Well crystallized and ho-
mogeneous marbles and silicious and compact limestones are the
best for construction purposes. These stones can be easily worked
and are beautiful in appearance, but are not always the most durable,
especially in cities. The color depends on impurities, such as oxide
of iron, carabonaceous matter, etc., and, as a general rule, the blue
and gray limestones are more durable than the white.f Loosely
cohering grains render stone liable to become friable and easily
weathered.
Pure dolomitic marble does not consist of a mixture of the
crystals of calcium carbonate and magnesium carbonate, but is
* John C. Smock, Bull, N, K State Museum, Vol. II., No. lo, Sept., 1890.
t U. S., X. Census Report. Article on " Building Stones."
VOL. XV. — 21
302 THE QUARTERLY.
composed of the double carbonate of calcium and magnesium
crystallized as one substance, and should contain 54.35 per cent.
CaCOj and 45.65 per cent. MgCOj. Dolomitic marble is very
highly valued for building purposes, and when pure is considered
by English and other authorities to be more durable in an acid
«
atmosphere than pure limestone. It seems yet to be proved, how-
ever, in the United States that a pure limestone is less durable than
dolomite. The coefficient of expansion is much less in calcite than
in dolomite, thus rendering the latter kind of limestone more liable
to physical decomposition than the former.
Prof. Hall considers magnesium limestone less durable than pure
limestone.*
The carbonate of magnesium is less easily soluble in carbonic
and other acids than the carbonate of calcium, and is a very com-
mon ingredient of many limestones. The pure calcite may thus
dissolve out first and pit the stone. The magnesium limestones
are also, as a rule, more porous, friable and less firm in character
than pure limestone. It has been proved, however, by experience
that the nearer a magnesium limestone approaches a dolomite the
more durable it is.
APATITE.
Anisotropic. Uniaxial. Hexagonal.
Composition: Ca5(ClF) (P04)3. H., 4.5 to 5. Sp. gr., 3.17
to 3.23.
Usual Appearance in Sections : Minute, slender, hexagonal
prisms, with sharply defined boundaries. Crystals often in clus-
ters. Also in grains. Cross-sections show regular hexagonal
boundaries.
Parellel Polarized Light :
Color. — Generally clear, bright white, may sometimes be col-
ored.
Index of Refraction. — «'na= 1-6388, e„. = 1.6346 (Lattermann).
Relief. — A little more marked than that of the colorless asso-
ciated minerals.
Cleavage. — Seldom observed microscopically.
Parting. — Long columnar crystals generally show a transverse
jointing, so that pieces may be more or less separated.
* U. S., X. Census Report. Article on ** Building Stones," p. 290.
MINERALS IN BUILDING STONES. 303
Pleochroism, — Only noticed in case of colored varieties.
Parallel Polarized Light, Crossed Nicols :
Double Refraction, — Weak.
Polarization Colors. — Scarcely exceed white of the first order
in thin sections. Generally in grayish blue tones.
Extinction, — As apatite is uniaxial, basal sections remain dark
during rotation of stage.
In all other sections the extinction is symmetrical being paral-
lel and perpendicular to the longitudinal axis.
Convergent Polarized Light: Basal sections show a crossf
without rings, and the optical character is — .
Alteration :
ArtificiaL — Easily soluble in hydrochloric and nitric acids.
Natural (tveathering), — Found perfectly fresh in decomposed
rocks, which is quite remarkable, considering its easy solubility in
acids.
Important Diagnostic Properties : Small size and hexagonal
type of prismatic crystals. — White color and low relief. — Sym-
metrical extinction. »
Differentiation :
{a) From Nephelite. — Relatively much smaller and longer than
the nephelite crystals.
{b) From clear Feldspar crystals. — By hexagonal cross-section.
Usual Associates in Sections ; Especially with nephelite, bio-
tite and hornblende, appears as one of the oldest secretions from
the magma, and hence often found as inclusions in other minerals.
General Occurrence in Building Stones : May be present in
many different rocks, and as an unimportant accessory constituent
in granite, syenite, mica schist, etc.
NEPHELITE, Elseolite.
Anistropic. Uniaxial. Hexagonal.
Composition : NagAIgSigOgy, with partial replacement of Na by
K or Ca. H , 5.5 to 6. Sp. gr., 2.55 to 2.65.
Nephelite (Nepheline).
Nephelite bears the same relation to elaeolite as sanidine does
to orthoclase. It occurs in the younger volcanic rocks in minute
hexagonal crystals.
304 THE QUARTERLY.
Elseolite.
Usual Appearance in Sections : Massive or grains.
Parallel Polarized Light:
Color, — Colorless.
Index of Refraction, — Wna= I -541 6, en»= 1-5376 (J. E. Wolff.)
Relief, — None.
Cleavage, — Imperfect parallel to prism cxP (loio) and base oP
(oooi). More marked in elaeolite than in nephelite.
Inclusions. — Microscopic needles of augite and hornblende quite
Common, also fluid and gas.
Fleochroistn, — None.
Parallel Polarized Light» Crossed Nicols :
Double Refraction, — Weak.
Polarization Colors, — Low^ generally grayish blue or white of
1st order.
Extinction, — As elaeolite is uniaxial, basal sections remain dark
during rotation of stage. In all other sections extinction takes
place and is symmetrical to cleavage lines when these appear.
Alteration r
Artificial, — Gelantinizes with acids.*
Natural {feathering), — Alters easily to fibrous zeolites, with bril-
liant polarization colors, muscovite and kaolin.
Important Diagnostic Properties : Massive. — Colorless. —
Low relief and low polarization colors. — Common presence of in-
clusions. — Gelatinization test with acids.
Differentiation : From other minerals by gelatinization test*
Usual Associates in Sections: Sodalite, orthoclase, micro-
cline, augite, titanite. etc.
General Occurrence in Building Stones : Essential in elaeolite
syenite, also occurs in augite, syenite, etc.
TOURMALINE, Shorl.
Anisotropic. Uniaxial. Hexagonal.
Composition : Uncertain, Ri8B2(Si05)4 R chiefly Al, K, Mn, Ca,
Mg, Li, F. H., 7 to 7.5. Sp. gr , 2.98 to 3.20.
Usual Appearance in Sections: In columnar crystals, fre-
* Microscopical Physiography of the Rock-Making Minerals^ Rosenbusch, Id-
dings' translation, p. 95,
MINERALS IN BUILDING STONES. 305
quently in staff-like individuals in bunched or radiating aggre-
gates. Cross-sections of crystals are hexagonal in shape or show
the outline of a spherical triangle.
Parallel Polarized Light:
Color, — Varies greatly, grayish blue and brown most common.
Index of Refraction. — ^97= 1.6240, oip-=^ 1.6444 (Des Cloi-
zeaux}.
Relief — Noticeable against the colorless rock constituents, and
rough surface.
Cleavage, — Not noticeable in sections, but there may be irregu-
lar cracks both transversely and longitudinally.
Pleochroism and Absorptioft, — Very strong. Distinct even in
light colored varieties, and increases with the depth of color. The
color varies from the natural color of the crystal to dark brown or
almost black, and the crystal becomes darkest when its longitudi-
nal axis is at right angles to the plane of polarization (or to the
vertical cross-wire in the eye-piece). The other minerals having
this very strong absorption are hornblende, dark colored mica and
allanite.
Parallel Polarized Light, Crossed Nicols :
Double Refraction, — Quite strong.
Polarization Colors, — Rather brilliant.
Extinction, — As tourmaline is uniaxial, basal sections remain
dark during rotation of stage. The extinction in all other sections
is symmetrical, being parallel and at right angles to the longitudi-
nal axis.
Convergent Polarized Light : Cross-sections show a sharp
cross, and the optical character is — .
Alteration : Not acted on by acids, and does not weather.
Important Diagnostic Properties : General shape of crystals
and color. — Pleochroism and strong absorption at right angles to
longitudinal axis. — Unweathered condition.
Differentiation : From dark Mica and Hornblende. — By ab-
sence of cleavage, and by the fact that the greatest absorption
takes place in tourmaline at right angles to the longitudinal axis,
while in mica and hornblende it takes place approximately parallel
to the cleavage lines, which, in hornblende, are parallel to the lon-
gitudinal axis.
3o6 THE QUARTERLY.
Usual Associates in Sections : Quartz, orthoclase, mica, stau-
rolite, garnet, etc.
General Occurrence in Building Stones : May be character-
izing accessory in granite. Found also in crystalline schists (espe-
cially clay schists), crystalline limestones, slate, clastic rocks, etc.
CHLORITE.
Including all members of the Chlorite group.
Anisotropic. Biaxial. Monoclinic.
The minerals of this group usually appear uniaxial, and crys-
tallize in part with rhombohedral symmetry and uniaxial optical
character.
Composition : May be considered as isomorphous mixtures of
H4(MgFe)3Si20a and H,(MgFeyAlFe)2Si09 (Rosenbusch).
H., 2 to 3. Sp. gr., 2.65 to 2.97.
Usual Appearance in Sections : In aggregates of small, flat
scales of irregular outline, with parallel, laminated structure.
Sometimes with hexagonal crystallographic outlines. May also
occur with fibrous structure, or in minute grains, as a pigment in
other minerals.
Parallel Polarized Light;
Color, — Generally green, may vary from greenish white to dark
green.
Index of Refraction, — e =i.S7S,<^ = i.576 (Haidinger).
Relief — None.
Cleavage. — Like mica, very perfect ; parallel to flat face, which
is considered to be the basal plane. In cross sections appears as
numerous parallel lines. Plates parallel to cleavage face never
show cleavage lines.
Pleochroism, — Varies, being more marked in dark colored varie-
ties. Basal sections are not pleochrbic, as the mineral is practi-
cally uniaxial.
Polarized Light, Crossed Nicols :
Double Refraction, — Very weak.
Polarization Colors, — Very low; therefore not noticed, on ac-
count of natural color of mineral.
*
Extinction, — Plates parallel to cleavage generally appear isotro-
pic, or only show faint illumination. In other sections extinction
is apparently parallel and at right angles to the cleavage.
MINERALS IN BUILDING STONES. 307
Convergent Parallel Light: Plates parallel to the cleavage
generally show an indistinct interference cross, which may open
into two hyperbolas, indicating monoclinic nature of crystallization.
Alteration : Acted on by hot hydrochloric acid, decomposed
easily by sulphuric acid.
Important Diagnostic Properties : Green color and low relief.
— Faint pleochroism. — No polarization colors. — Symmetrical ex-
tinction and usual uniaxial character.
Differentiation : From Serpentine. — By being generally more
pleochroic and not having the aggregate structure of serpentine.
Usual Associates in Sections : Being very often of secondary
origin, derived from aluminous varieties of mica, pyroxene, amphi-
bole, garnet, etc., it is often found with these minerals and also
with magnetite.
General Occurrence in Building Stones ; Very widely dissem-
inated in rocks. Found in granite and gneiss as a rare character-
izing accessory, in chlorite schists as an essential constituent, and
also in diorite, diabase, serpentine and clay slates.
Economic Effect in Building Stones : The characteristic color
which gives the name of greenstone to the dio rites and diabases is
due principally to the secondary chlorite contained in them.
Viridite :
A name used for a green decomposition product related to chlo-
rite and serpentine.
STAUROLITE.
Anisotropic. Biaxial. Orthorhombic.
Composition: Fe(A10)4(A10H)(Si04)2, but varying, may con-
tain Mg or Mn. H., 7 to 7.5. Sp. gr., 3.65 to 3.75.
Usual Appearance in Sections : As single individuals or twins,
may assume form of grains. Forms and twinning at 90° and 1 20*^
like the macroscopic crystals. Absence of elongated forms cha-
racteristic.
Cross sections acutely rhombic or almost hexagonal, longitudi-
nal sections rectangular.
The twinning often only recognized optically.
3o8 THE QUARTERLY.
Parallel Polarized Light :
Color, — Yellowish to reddish-brown.
Index of Refraction. — ?p = 1.749 (^^s Cloizeaux).
Relief, — Very high and rough surface.
Cleavage, — Variable. Prismatic cleavage may appear, also a
pinacoidal cleavage parallel to the short diagonal.
Parting. — Occurs parallel to the base oP (ooi).
Pleochroism. — Distinct but not strong, may be more marked
around interpositions. In the direction of c, reddish; in the direc-
tion of a and b, yellowish red, or with tinge of green.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Strong.
Polarisation Colors. — Brilliant even in very thin sections.
Extinction. — Symmetrical, being parallel and at right angles to
cleavage cracks and longitudinal axis, except in cross sections,
when It bisects the prism and cleavage angles.
Alteration : Not acted on by hydrochloric acid, partially solu-
ble in sulphuric acid. Decomposition rare.
Important Diagnostic Properties: Characteristic shape and
twin structure like macroscopic crystals. — Yellowish brown color.
Strong relief and rough surface. — Faint pleochroism. — Brilliant
polarization colors. — Generally fresh appearance.
Differentiation: From Titanite. — In convergent light, the
axial plane is shown to be in the longer diagonal of the cross sec-
tion, while in titanite it is in the shorter diagonal.
Usual Associates in Sections: Quartz, orthoclase, cyanite,
mica, garnet, etc.
General Occurrence in Building Stones : In Archaean rocks,
gneiss, especially in mica schists, slates, etc.
THE ORTHORHOMBIC PYROXENES.
Enstatite and Hypersthene.
Anisotropic Biaxial. Orthorhombic-
Composition: (Mg Fe) SiOj. Hypersthene contains more iron
MINERALS IN BUILDING STONES. 309
than enstatite, and the optical character of hypersthene begins to
show with 10 per cent, of iron.
Resembling the Monoclinic Pyroxenes in sections and dis-
tinguished from them by the following characters :
Columnar or fibrous structure common.
Colors vary a little more than in the monoclinic pyroxenes, be-
cause, on account of the strong pleochroism, the color depends a
good deal on the position of the section relative to the crystallo-
graphic axes.
In addition to the prismatic cleavage (angle 92°) the massive
varieties show a good parting parallel to the brachy pinacoid
oc P a (010), and there may be also an imperfect parting parallel
to the macro pinacoid oc P a (100). (Dialjage shows parting
parallel to the ortho pinacoid or. P 6c (100), but is not pleochroic).
May contain inclusions of the iron ores and metallic or sub-
metallic scales (generally brownish), arranged in regular order and
giving metallic sheen to the cleavage faces.
Pleochroism, which is more intense as the iron percentage in-
creases, is generally noticed as producing a decided change in
color (in case of hypersthene from brownish red to greenish, paral-
lel to c axis).
Extinction always symmetrical, being parallel to the pinacoidal
cleavages, and bisecting the angles of the intersecting prismatic
cleavages.
Alteration :
ArHficial.-^-lvi general not attacked by acids. Hypersthene
partly soluble in hydrochloric acid.
Natural [weathertftg), — Alters to fibrous aggregates of bastite or
to serpentine, limonite, amphibole, etc. Hypersthene withstands
decomposition better than enstatite.
Usual Associates in Sections : Plagioclase, augite, chrysolite,
magnetite, etc., less frequently with hornblende, biotite, quartz, etc.
General Occurrence in Building Stones: Rare in quartzose
rocks. Enstatite in norites, gabbros, peridotites, etc., and in chry-
solite, basaltic and Archaean rocks, trachytes and andesites. Hy-
persthene in the more basic members of the granular eruptive rocks,
gabbros, norites, etc., and in porphyritic trachytes, andesites and
lavas. Hypersthene is found with plagioclase (labradorite) in the
norite, called " Au Sable granite."
3IO THE QUARTERLY,
CHRYSOLITE, Olivine.
Anisotropic. Biaxial. Orthorhombic.
Composition: (MgFe)2Si04. H., 6.5 to 7. Sp. gr., 3.27 to
3.57.
Usual Appearance in Sections: Tabular crystals, incipient
forms of growth, grains or granular aggregates. Longitudinal
sections more or less lath shaped, with corners truncated. Out-
lines of crystals often rounded or corroded.
Parallel Polarized Light:
Color, — Nearly colorless to greenish white ; may appear reddish
when altering.
Index of Refraction. — ^^^ = 1.678.
Relief, — Strong, with rough surface.
Cleavage, — More or less distinct parallel to the brachy oc P dc
(010) and macro oc P oc (100) pinacoids.
There is also an irregular fracturing, which increases with the
alteration into serpentine.
hiclusions, — The iron ores, etc., frequent.
Pleochroism, — In general, none.
Parallel Polarized Light, Crossed Nicols:
Double Refraction — Very strong.
Polarization Colors, — Brilliant.
Extinction, — Always symmetrical, being parallel and at right
angles to cleavage lines.
Alteration :
Artificial, — Decomposed by hydrochloric and sulphuric acids,
with separation of gelatinous silica.
Natural [weathering), — These processes are very important.
1°. Proper weathering.
2°. Alteration into serpentine, which is most common. The
alteration starts from the surface and cracks, producing fibres of
serpentine, which stand at right angles to the edges and cracks.
As serpentization proceeds, new cracks form, due to increase in
volume, and process may continue until a complete net of serpen-
tine fibres is formed, replacing the chrysolite. Observations show
that under present conditions this strong tendency to decompose
into serpentine may not take place.*
* Article on " Building Stones,*' Tenth U. S. Census.
MINERALS IN BUILDING STONES. 311
3°. Alteration into fibrous amphibole.
Important Diagnostic Properties : Colorless to greenish
white. — High relief and rough surface. — Pinacoidal cleavage,
irregular fracturing and alteration into serpentine. — Brilliant polar-
ization colors. — Symmetrical extinction.
Differentiation :
(a) From Orthorhombic Pyroxenes. — By absence of prismatic
cleavage and pleochroism.
(b) From light-colored Monoclinic Pyroxenes. — By symmet-
rical extinction.
(c) From Sanidine. — By rough surface and brilliant polarization
colors.
(d) From minerals of similar habit. — By test for gelatiniza-
tion.*
Usual Associates in Sections : Augite, plagioclase, nephelite,
hornblende, biotite, magnetite, etc. Almost never with primary
quartz and orthoclase.
General Occurrence in Building Stones : In basaltic rocks,
traps and crystalline schists. Also in dolomitic limestone and ser-
pentine.
lOLITE, Cordierite , Dichroite.
Anisotropic. Biaxial. Orthorhombic.
Composition: Mg3(AlFe)gSi8028. H., 7 to 7.5. Sp. gr., 2.6
to 2.66.
Usual Appearance in Sections : In grains, sometimes in crys-
tals.
Parallel Polarized Light :
Color. — Generally colorless; more rarely yellowish, blue, or
violet, depending on position of section.
Index of Refraction. — ^ = 1. 541 (approx.).
Relief — None, and plain surface.
Cleavage. — Very variable, sometimes observed in thin sections
parallel to brachy pinacoid a P oc (010).
An irregular parting often seen.
Pleochrotsm. — Hardly noticed in thin sections, but often quite
* Microscopical Physiography of the Rock Making Minerals^ Rosenbusch, Iddings*
translation, p. 95.
312 Tllh QUARTERLY.
strong in thick sections from the prism zone (from yellowish white
or brown to blue).
Pleochroic halos, surrounding microscopic inclusions, are com-
mon and bright yellow in color.
Parallel Polarized Light, Crossed Nicols :
Double Refraction, — Weak.
Polarization Colors, — Seldom exceed yellow of the ist order,
generally blue, gray, and white tones, like quartz.
Extinction. — Symmetrical when cleavage shows, taking place
parallel and perpendicular to cleavage cracks.
Alteration :
Artificial. — Only slightly acted on by acids.
Natural (feathering). — Readily alters to more or less fibrous
or lamellar aggregates, or to yellowish or greenish products. The
decomposition commences along the crevices.
Differentiation : From Quartz. — By treating section with hy-
drofluosilicic acid; when the evaporated solution yields char-
acteristic prismatic crystals of magnesium fluosilicate. By presence
of decomposition along the crevices, and by pleochroism in thick
sections.
Usual Associates in Sections : Quartz, orthoclase, plagio-
clase, garnet, biotite, the iron ores, etc.
General Occurrence in Building Stones : May be character-
izing accessory in granite (rare), but its real home is in the gneiss
formation, cordierite-gneiss.
MONOCLINIC PYROXENE, Augite, etc.
Including the monoclinic minerals of the Pyroxene family, which
show distinctly the characteristic cleavage parallel to an almost
right angled prism.
Anisotropic. Biaxial. Monoclinic.
Composition : RSiOj, R = Ca, Mg, Mn, Fe, Al chiefly.
H., 5 to 6. Sp. gr., 3.2 to 3.6.
Usual Appearance in Sections : In irregularly bounded in-
dividuals, well developed crystals, grains, and acicular microliths.
Prism angle = 87° 6' (important in cross-sections).
Habit varies with the chemical composition, following the
general rule:
MINERALS IN BUILDING STONES. 313
Pyroxenes of the diopside and acmite series, long columnar
crystals with subordinate prism planes.
Pyroxenes of the atigite series, short prismatic crystals and
grains.
Dicdlage ^tn^x^Xy shows fibrous structure parallel to the vertical
c axis.
Sections nearly at right angles to the vertical c axis are octago-
nal or square with truncated corners, while those parallel to the
c axis are lath-shaped.
Twinning. — Common, usually the twining plane is the ortho
pinacoid oc Poc (100).
Parallel Polarized Light :
Color, — From almost colorless through green to brown, may
even be violet. The common pyroxene in granite, etc., generally
green, in eruptive rocks generally greenish black.
Index of Refraction. — /5 = 1.70 (augite from Borislau by
Tschermak).
Relief — Strong, and rough surface.
Cleavage, — More or less perfect parallel to prism of 87° 06'. The
cleavage cracks are distinct and numerous, but do not generally
run uninterruptedly through crystal. In some basaltic rocks there
are augites showing no cleavage. The cleavage is not so perfect
as that of amphibole.
Parting, — Diallage has distinct parting parallel to the ortho
pinacoid oc P <x (100). Long prismatic crystals may show an ir-
regular parting approximately at right angles to the vertical c
axis.
Inclusions, — Tabular microscopic interpositions, similar to those
in bronzite, may occur in diallage. The iron- ores, apatite, etc.,
may occur in augite.
Pleochroism,'^\is^\2\\y feeble, and in general only shows itself as
different shades of the body color.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Strong.
Polarization Colors. — Brilliant, especially noticed in the colorless
pyroxenes.
Extinction, — The extinction is always symmetrical in sections
showing intersecting cleavage lines, when it bisects the angles of
the cleavage. The extinction, in sections showing parallel cleavage
314 THE QUARTERLY,
lines, is only symmetrical when the section is parallel to the ortho
pinacoid oc P <x (lOo); in all other sections an extinction angle is
observed.
The extinction angle is large in all pyroxenes except acmite,*
and varies with the chemical composition from 36° 30' to 54®.
The maximum extinction angle is only obtained when the sec-
tion of the crystal is parallel to the clino pinacoid oc Poc (010),
and it varies from this angle to 0°, when the section is parallel to
the ortho pinacoid oc P^ (lOo).
Alteration :
Artificial. — In general not attacked by acids.
Natural {zveathering). — The processes of alteration are very dif-
ferent, depending on the chemical composition ; the ferruginous
varieties being apt to decay more rapidly than those poor in iron.
Diopside (Ca, Mg pyroxene) may alter to greenish, fibrous,
serpentme aggregates.
Diallage (near diopside in composition, often containing Al)
may alter to serpentine or chlorite, with more or less calcite and
epidote.
Augite (Ca, Mg, Fe, Al pyroxene) generally alters to chlorite,
or may change by further alteration to mixtures of carbonates,
limonite, epidote, clay and quartz.
Uralitization may take place, which is a change into amphibole
with the amphibole cleavage, while retaining the exterior shape of
pyroxene.
Pyroxene seems more likely to decay than amphibole.f
Important Diagnostic Properties : Greenish or brown color. —
Rather strong relief — Prismatic cleavage of nearly 90°. — Very
slight pleochroism. — Brilliant polarization colors. — Characteristic
large extinction angle 36° 30' to 54°.
Differentiation :
• {a) From the Orthorhombic Pyroxenes. — By usually much
fainter pleochrism, and by characteristic extinction angle. The
orthorhombic pyroxenes always have symmetrical extinction.
{b) From Amphibole — See under amphibole.
[c) From Epidote. — By examination in convergent light. The
* Acmite, the soda pyroxene, has small extinction angle 4** -5°, and is not very
transparent.
f John Smock, Bull. A'. K S.ate Mus.^ No. 10, 1890.
MINERALS IN BUILDING STONES. 315
plane of the optic axes being parallel to the longitudinal axis and
cleavage cracks, while in epidote it is at right angles. The maxi-
mum extinction angle is also larger.
Usual Associates in Sections: Augite with plagioclase, mag-
netite, nephelite, chrysolite, biotite, etc., more rarely with ortho-
clase, hornblende and quartz.
General Occurrence in Building Stones : Among the most
widely distributed of the rock-forming minerals. Found in granite,
gneiss, crystalline schists, diabase, gabbro, trap, basalt, limestone,
serpentine, etc.
Economic Effect in Building Stones :
Granite. — May be present, as characterizing accessory. More
abundant than generally supposed, and formerly often taken for
hornblende, with which it is frequently associated in the same
granite.
Pyroxene is more brittle than hornblende, has not so easy a
cleavage, and, during process of dressing the stone, is more apt to
crack or chip out apd pit the surface. It is also more likely to
occur in bunches than hornblende.
Pyroxene granite is therefore not so durable as hornblende
granite, and it is important to distinguish between them. The
Quincy granite contains very brittle pyroxene.
Trap and Basalt. — Essential constituent with plagioclase. The
rock is compact, tough, dark in color, and used for paving ; but,
on account of smallness of blocks and difficulty of working, these
rocks are not much used for buildings.
AMPHIBOLE, Hornblende.
Anisotropic. Biaxial. Monoclinic.
Composition : R4(SiOs)4, with R = Ca, Mg, Fe chiefly, also
may contain Al, Na, Mn. H., 5 to 6. Sp. gr., 2.9 to 3.4.
Usual Appearance in Sections : Without regular crystallo-
graphic boundaries, except in porphyritic rocks. Crystals simple
in form of prismatic habit, with prism angle of 124° 30'. Some
varieties have tendency to form long blade like crystals. Often
fibrous. Intergrowths with pyroxene and biotite occur. Cross
sections are acutely rhombic, generally with acute angles truncated.
Longitudinal sections are lath shaped, and ends may be frayed out
3i6 THE QUARTERLY.
instead of terminated by planes. Crystals less often microlitic than
pyroxene.
Twinning. — Frequent, parallel to the ortho pinacoid oc P oc (loo).
Parallel Polarized Light :
Color, — From colorless, through green to brown.* Common
hornblende generally green.
Index of Refraction. — ^/i= 1.642 (common hornblende from
Volkersdorf).
Relief. — Quite considerable, but not so great as pyroxene.
Cleavage, — Pefect, parallel to the prism of 124*^ 30'. Generally
appears in thin sections as sharp cracks crowded closely together.
More perfect than in pyroxene.
Inclusions. — The iron-ores, apatite, etc., may be found in com-
mon hornblende.
Pleochroism. — All colored amphiboles show pleochroism, which
is stronger the darker the color of the variety. The differences of
absorption are very marked, being greatest in the general direc-
tion of the cleavage lines, in longitudinal sections. Marked differ-
ences in absorption are also characteristic of the mineral species
biotite, tourmaline, and allanite.
Parallel Polarized Light, Cross Nicols :
Double Refraction. — Quite strong.
Polarization Colors. — Ratlier bright.
Extinction. — Is always symmetrical in sections showing inter-
secting cleavage lines, when it bisects the angle of the cleavage.
In sections showing parallel cleavage lines, it is only symmetrical
when the section has been taken parallel to the ortho pinacoid
oc P oc (100). In all other sections an extinction angle is observed.
This extinction angle is smaller than in pyroxene, varying with
the chemical composition from o°-20°. In common hornblende
15^-18° ; in the basaltic hornblendes o°-io°. The maximum ex-
tinction angle is only obtained when the section of the crystal is
parallel to the clino pinacoid ocPoc (010), and it varies from this
angle to 0°, when the section is parallel to the ortho pinacoid
oc P oc (100).
Alteration :
Artificial, — In general not affected by acids.
Natural {weathering). — The processes of alteration differ, de-
* Glaucophane, the soda amphibole, is blue.
MINERALS IN BUILDING STONES, 317
pending on the chemical composition. The more highly ferrugin-
ous varieties are apt to decompose more rapidly than those poorer
in iron.
Tremolite (Ca, Mg amphibole) into talc.
Actinolite (Ca, Mg, Fe amphibole) sometimes decomposed to
serpentine like matter.
Common hornblende (Ca, Mg, Fe, Al amphibole), into chlorite,
with secretion of epidote or calcite and quartz. The hornblende
frays out and becomes fibrous during this change into chlorite.
Important Diagnostic Properties : Green to brown color. —
Perfect cleavage parallel to prism of 124° 30^ — Strong pleochro-
ism and absorption. — Bright polarization colors. — Extinction angle
0° to 20°.
Differentiation :
{a) From Pyroxene. — By much stronger pleochroism, absorp-
tion, and by cleavage and extinction angle. In pyroxene the
cleavage is less perfect, and is parallel to prism of 2>7^ Q6'y and the
extinction angle is much larger, varying from 36° to 54°.
{b) From Biotite. — By the extinction in the latter being about
parallel and normal to the cleavage. Both have strong pleochro-
ism and absorption, but biotite shows very slight pleochroism in
sections parallel to the cleavage.
(c) From Tourmaline, — By presence of cleavage, and by the
fact that absorption is most marked about parallel to the longitu-
dinal axis (also to cleavage lines), while in tourmaline the absorp-
tion is strongest at right angles to the longitudinal axis.
(d) From the Orthorhombic Pyroxenes. — By extinction angle,
the latter always having symmetrical extinction. Pleochroism is
strong in the colored varieties of both species, but in amphibole
it appears more generally as a variation in the body color; while
in the orthorhombic pyroxenes a change in color is often noticed
(in case of hypersthene, from brownish red to greenish parallel to
c axis).
Usual Associates in Sections : Orthoclase, plagioclase, quartz,
biotite, more rarely with augite and olivine (tremolite with calcite).
•Xieneral Occurrence in Building Stones : Amphibole comes
next to pyroxene in importance and distribution of the dark col-
ored ferruginous rock forming minerals, and is supposed to differ
from pyroxene by having formed from slowly cooling magma.
VOL XV. — 22
3i8 THE QUARTERLY.
As a rule, hornblende occurs in rocks with a large percentage of
silica, associated with quartz and orthoclase; while augite generally
occurs in rocks of a basic nature, associated with plagioclase and
little or no free silica. Found in granite, syenite, gneiss, diorite,
schists, crystalline limestone ; sparingly in sandstone, serpentine,
etc. May occur in granite with dark mica, but never with light
muscovite (Haw's Lith, of New Hampshire).
Economic EfTect in Building Stones:
Granite and Gneiss. — Characterizing accessory, and generally
in granular form of a dark green or black color. It is tough and
less brittle than pyroxene (having better cleavage), and takes a
better polish. Hornblende granite is, therefore, generally pre-
ferred to pyroxene granite. It is easier to polish than mica, and,
unless showing a tendency to decompose, is usually considered to
be a good thing in granite.
Syenite. — Essential constituent with orthoclase. It is tough
and acts as a good binding material, making syenite a good stone
to withstand shocks.*
Diorite, also known as trap or greenstone. — Essential with
plagioclase. Gives dark color to rock, and being tough and dura-
ble makes rock also durable; but, on account of smallness of
blocks and difficulty of working, these rocks are not much used
for building.
MICA GROUP. .
Biotite, Phlogopite, Muscovite.
Anisotropic. Biaxial. Monoclinic.
May appear hexagonal or orthorhombic.
Composition :
Biotite (black mica) = (HK)2(MgFe)2Al2(Si04)3, approx.
Phlogopite = a magnesium mica, near biotite, but containing
little Fe.
Muscovite (white mica) = H2(KNa)Al2(Si04)3, with some re-
placement by Mg or Fe. H., 2 to 3. Sp. gr., 2.75 to 3.2.
Usual Appearance in Sections : Without crystallographic
boundaries except the basal planes. Notched and jagged shreds,
* J. L. Greenleaf, Building Stones^ etc^ School of Mines' Quarterly, Vol. I.,
pp. 28 and 52.
MINERALS IN BUILDING STONES. 319
etc. When distinctly crystallized appear in thin hexagonal plates,
whose plane angles are 120°.
Parallel Polarized Light:
Color. — Depends on chemical composition. Biotites, brown,
green or red to almost opaque. Muscovites and phlogopites, col-
orless to light yellow to greenish.
Index of Refraction. — /5 = 1. 541 (muscovite by Bauer).
Relief — Low, and plain surface.
Cleavage. — Very perfect parallel to base oP (001). Basal sec-
tions show no cleavage, but all other sections show many sharp,
parallel cleavage lines.
For percussion anH pressure figures, see reference given below.*
Faults and planes of separation, parallel to lines of pressure figure,
are common in rock making micas.
Inclusions. — Very often arranged parallel to lines of pressure
figure.
Pleochroism, — Varies with color, being very strong in the colored
varieties. All micas show strong absorption about parallel to the
cleavage-lines. Cleavage-plates are only slightly pleochroic (es-
pecially in biotite). The same strong absorption is only noticed
in basaltic hornblende, tourmaline and allanite.
Parallel Polarized Light, Crossed Nicols:
Double Refraction, — Very strong. '
Polarization Colors. — Brilliant.
Extinction. — About symmetrical, being nearly parallel and at
right angles to cleavage-lines. Basal sections of biotite (the ap-
proximately hexagonal mica) may appear isotropic.
Convergent Polarized Light : Basal cleavage plates always
show brilliant interference figures, generally biaxial in character.
The axial angles vary greatly, being usually small for biotite (may
appear uniaxial) and large for muscovite.
Alteration :
Artificial. — Biotites and phlogopites attacked by sulphuric acid
at high temperatures. Muscovites but slightly attacked by acids.
Natural (iveathering). — Biotites decompose quite easily, lose
color and may become completely bleached ; this appears to be
* Microscopical Physiography of Rock Making MineralSy Rosenbusch, Iddings'
Translation, p. 256.
320 THE QUARTERLY.
due to a leaching out of the iron. May alter to green chlorite,
with a fraying out of the mica, or may finally turn into a mixture
of carbonates or epidote with the iron ores and quartz.
Phlogopites may alter to fibrous, scaly masses, apparently chiefly
talc.
Muscovites are characterized by their freshness, and do not seem
to suffer from weathering.
Important Diagnostic Properties : General absence of crys-
tallographic boundaries. — Perfect basal cleavage. — Strong absorp-
tion, and strong pleochroism in colored varieties. — Almost sym-
metrical extinction.
Differentiation :
( a) From Hornblende. — Black mica has extinction about
parallel and normal to the cleavage, while hornblende may have
extinction angle of from o° to 20°. Both have strong pleochroism
and absorption, but biotite shows very slight pleochroism in sec-
tions parallel to the cleavage.
{b) From Chlorite. — By bright polarization colors, and gener-
ally stronger pleochroism.
{c) From other minerals by perfect basal cleavage.
Usual Associates in Sections: Biotite (black mica) with
quartz, feldspar, hornblende, augite, magnetite, etc.; intergrown
with muscovite in true granite only.
Phlogopite with calcite, serpentine, etc.
Muscovite (white mica) with quartz, feldspar, tourmaline, etc.
General Occurrence in Building Stones : Biotite found in
nearly all rocks, common in granite, gneiss, schists, etc. ; also in
the eruptive rocks.
Phlogopite found chiefly in crystalline limestones and serpen-
tine.
Muscovite found in granite, gneiss, schists, sandstone, clays and
slates ; but not in the volcanic massive rocks.
Economic Effect of the Micas in Building Stones :
Granite. — One of the characterizing accessory minerals with
quartz and feldspar. The mica may be black or white and help to
give color to the granite. It does not polish or keep its polish so
well as quartz and feldspar, owing to its greater softness. It is
better to have it distributed uniformly in rocks in many small
crystals rather than in a few large plates. Foliated structure may
MINERALS IN BUILDING STONES, 321
be caused by parallel position of the plates, resulting in lines of
weakness. The ferruginous micas are more apt to decay than the
other component minerals.
According to Rosenbusch there is usually less quartz and more
plagioclase irt biotite granite than in muscovite granite.
Gneiss. — May contain large percentage, and being stratified is
more likely to split than granite.
Mica Schist. — Essential together with quartz. When rock is
fine grained and compact it makes pretty fair building material ;
but poor if coarse grained, especially if the mica is of the black or
ferruginous variety.
Sandstone. — Occurs as an impurity ; but may even give char-
acter to the stone, and render it liable to easy decay, especially if
of the ferruginous variety (biotite).
In the sandstone of Trinity Church, N. Y., the micas are the
most decayed of all the minerals, and the decay seems to have
progressed in the more weathered portions,*
EPIDOTE.
Anistropic. Biaxial. Monoclinic.
Composition : Ca2Al2(A10H) (Si04)3, with some Fe replacing Al.
H., 6 to 7. Sp. gr., 3.25 to 3.5.
Usual Appearance in Sections : In columns, more or less
elongated parallel to ortho axis b, or in irregular grains or aggre-
gates.
Parallel Polarized Light :
Co/or. — From almost colorless through pale yellow to pale
green.
Index of Refraction.— ?P = 1.754 (Klein).
Relief — Strong, and rough surface.
Cleavage, — Perfect parallel to the base oP (00 1), shows in sharp
cracks which are however^not very numerous, and appear parallel
to the general direction of extension.
Cleavage may also appear parallel to ortho pinacoid (xP 6c
(100).
Pleochroism, — Varies with the color, being faint in the light col-
* Thomas Egleston, Ph.D. "The Cause and Prevention of Decay of Building
Stones,*' Trans, Am, Soc. C.E,^ Vol. XV., 1886.
322 THE QUARTERLY,
ored ones. In crystals from Sulzbach it is very strong, green to
colorless or light yellow. Not so strong as in hornblende.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Very strong.
Polarization Colors, — Brilliant.
Extinction. — Symmetrical to the cleavage in sections parallel to
the direction of elongation. In other sections the extinction angle
may vary from o° to 28.®
Alteration : Partially decomposed by hydrochloric acid. Not
Important Diagnostic Properties : Color yellowish to green-
ish. — Strong relief and rough surface. — Faint pleochroism. —
Polarization colors brilliant.
Differentiation :
(a) From light-colored Monoclinic Pyroxene. — By parallel
extinction in elongated sections, and by extinction angles being
smaller than those of pyroxene in other sections. By having plane
of optic axes at right angles to cleavage lines (running parallel to
longitudinal axis), while in pyroxene plane of optic axes is parallel
to prismatic cleavage lines.
[b) From Chlorite. — By relief and general appearance of
crystals.
Usual Associates in Sections: Feldspars, biotite, hornblende,
augite (more rarely), quartz, chlorite, etc.
General Occurrence in Building Stones : It is essentially a
decomposition product, resulting from the alteration of the feld-
spars, and a side product of the chloritization of calcium, iron and
magnesium silicates.
May be present in granite as characterizing accessory, as at
Dedham, Mass. Common in many crystalline rocks, as syenite,
gneiss, schists (especially those containing hornblende), serpentine,
etc. ; and may be present in slates as decomposition product.
TITANITE, Sphene.
Anisotropic. Biaxial. Monoclinic.
Composition: CaSiTiOg. H., 5 to 5.5. Sp. gr., 3.4 to 3.56.
Usual Appearance in Sections: Well crystallized in wedge
shaped cr>stals, or in irregular grains. The sections are com-
monly acute rhombs or long lath like shapes.
MINERALS IN BUILDING STONES. 323
Twinning. — Only seen between crossed nicols, when the twin-
ning boundary bisects the acute angles of the rhomb.
Parallel Polarized Light:
Color. — Colorless to yellowish or reddish brown, may be only
translucent.
htdex of Refraction. — ^ = 1.905 — I.910.
Relief — Very high, and rough surface.
Cleavage. — Imperfect {)arallel to the prism, only appears as a
few rough cracks. As the prism is not a predominant form the
cleavage cracks are not parallel to any crystallographic boundary,
which fact is characteristic of titanite.
Pleochroism. — Varies with the color, being more distinct in col-
ored crystals. Not so distinct as that of hornblende.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Not yet measured, but does not appear to
be great.
Polarization Colors. — Not generally noticeable on account of the
strong dispersion.
Extinction. — Extinction angles are noticed, but are not charac-
teristic. There may be no complete extinction in white lights
owing to the strong axial dispersion.
Alteration :
Artificial. — Partly soluble in hot hydrochloric acid, completely
decomposed by sulphuric acid.
Natural {weathering). — When decomposing it bleaches, loses
lustre, the lime separates out and a dull alteration product remains.
Important Diagnostic Properties: Strong relief and rough
surface. — Common acute rhombic shape of section. — Cleavage not
parallel to any crystallographic outline.
Differentiation : From Staurolite. — In convergent light the
axial plane is shown to be in the shorter diagonal of the cross-
section, while in staurolite it is the longer diagonal.
Usual Associates in Sections . Orthoclase, plagioclase,
augite, hornblende, biotite, chlorite, quartz, etc.
General Occurrence in Building Stones : Only as an acces-
sory in granite, syenite, gneiss, schists, diorite, granular limestone,
etc. According to Frazer it seems to be a necessary accessory
mineral in the amphibole granites and syenite. It also occurs in
the Archaean rocks rich in MgO and FeO.
324 THE QbARTERLY.
FELDSPAR GROUP.
Orthoclase, Microcline and the Plagioclases.
ORTHOCLASE.
Anisotropic. Biaxial. Monoclinic.
Composition : KAlSijOe, with some roplacetnent by Na.
H., 6 to 6.5. Sp. gr., 2.44 to 2.62.
Usual Appearance in Sections : Without regular crystallo-
graphic boundaries. Rarely in rods. May appear in well defined
crystals in porphyrttic rocks, with habit of crystals more or less
tabular parallel to the clino pinacoid oc P oS (010), or rectangular
much extended parallel to the clino (a) axis. Intergrowths with
microcline and plagioclase important.
Twinning, — Very common, generally after the Carlsbad law.
The twinning boundary more or less divides the section longitud-
inally, being parallel to the edges of the crystal, or is an irregularly
bent or jagged line. Twinning after other laws less common.*
Parallel Polarized Light:
Color, — Colorless, or tinged red by oxide of iron.
Index of Refraction. — /5/> = 1.5239 (Des Cloizeaux).
Relief, — None, and smooth surface.
Cleavage, — Very important. Perfect parallel to base oP (ooi)
and clino pinacoid oc P oc (oio>. The cleavage lines are only seen
in thin sections, and are parallel or intersect at angles of from 90®
to 63° 53'. Not, as a rule, so distinct as the cleavage of mica,
hornblende, etc.
Pleochroism, — None.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Very weak.
Polarisation Colors. — Faint, gray to yellow, not so bright as
colors of quartz and plagioclase.
Extinction. — The extinction angles, with reference to the cleav-
age lines, vary from 0° (in sections parallel to the ortho axis) to
3°-7® (rarely 12°) in other sections. Hence, as a rule, extinction
angles are small.
* Microscopical Physiography of the Rock Making Minerals^ Rosenbusch, Iddings'
translation, p. 278
MINERALS IN BUILDING STONES. 325
Alteration :
Artificial. — Practically insoluble in acids.
Natural {weathering), — Leaching out of the potash produces an
alteration into kaolin* or muscovite. The alteration generally
commences along the cleavage cracks, producing aggregates of a
perfectly uniform, colorless substance, strongly doubly refracting.
When the alteration has progressed very far the whole feldspar
appears opaque or cloudy, and no perceptible change takes place
between crossed nicols. Epidote is often noticed as a decompo-
sition product.
Important Diagnostic Properties: Generally without crys-
tallographic boundaries. — Commonly twinned. — Low relief —
Cleavage. — Low polarization colors. — Frequently more or less de-
composed.
Usual Associates in Sections : Quartz, biotite, muscovite and
hornblende ; more rarely augite and plagioclase.
Gene^ral Occurrence in Building Stones : Found as the pre-
vailing feldspar in granite (rich in quartz), syenite, gneiss, crystal-
line schists, etc. May also be present in limited quantity in sand-
stone, limestone, clays and slates.
Sanidine.
This glassy, clear variety of orthoclase, occurs in the later erup-
tive rocks; while orthoclase occurs in the older massive and
Archaean rocks. Sanidine often has a rude parting parallel to the
ortho pinacoid oc P ex (100), which may be noticed in sections so
thick that the cleavage is not seen. It often encloses associated
minerals, and intergrowths with plagioclase are common. In gen-
eral it shows no sign of decomposition, and its associates are the
same as those found with orthoclase, with the addition of augite,
nephelite and leucite.
MICROCLINE.
Anisotropic. Biaxial. Triclinic.
Composition: KAlSijOg. H. 6 to 6.5. Sp. gr., 2.54 to 2.57.
Usual Appearance in Sections : As a rock constituent in irreg-
ular grains, never in regular crystals. Grains are scarcely ever
* This change to kaolin in granite called by Dolomieu " La maladie du graniij'^
326 ' THE QUARTERLY,
simple individuals, but polysynthetic masses, twinned after the
Albite and Pericline laws. The lamellae are microscopic in thick-
ness. Intergrowths with orthoclase and albite are frequent.
The general characters and alteration are the same as with or-
thoclase.
Differentiation :
(a) From Orthoclase. — The extinction angle, on the base oP
(ooi), with the cleavage parallel to the clino pinacoid oc P oT
(oio) is + 15° 30'f while in orthoclase it is 0°. This can only be
easily observed in simple crystals.
(b) From all other Feldspars.— All sections, except those par-
allel to the clino pinacoid oc P yT (010), show between crossed
nicols the characteristic gridiron structure or crossed rectangular
grating of microcline. Lamellae are not generally so broad as in
the plagioclases.
General Occurrence in Building Stones : With orthoclase,
often almost replacing it in granite, syenite, gneiss, etc. Formerly
classed as orthoclase. Important in Egyptian granite, less fre-
quent in quartz and other porphyries.
THE PLAGIOCLASES.
Anisotropic. Biaxial. Triclinic.
Composition:
Albite, Na Al SiA-
Oligoclase, n (Na Al SijOg) -f Ca AlgSijOg, « = 2 to 6.
Labradorite, Na Al SijOg + n (Ca AlgSijOg), « = i, 2 or 3.
Anorthite, Ca Al^SijOg.
H., 6 to 7. Sp. gr., 2.59 to 2.72.
Usual Appearance in Sections : Not always with crystallo-
graphic boundaries. Well-defined crystals, resembling those of
orthoclase, occur only in porphyritic rocks. Dimensions of pla-
gioclase crystals vary greatly from microlitic upwards.
Lath-shaped forms very common, especially in basaltic rocks.
Iwinning, — Polysynthetic twinning, after the Albite law, is very
common. The twinning appears between crossed nicols as a se-
ries of dark and light bands, which seem to be broader in the
basic than in the acid series. The twinning is not observed in
MINERALS IN BUILDING STONES. 327
sections parallel to the brachy pinacoid oc P ot (010). In some
cases polysynthetic twinning, after both the Albite and Pericline
laws, may take place at the same time, giving rise to a structure
similar to that of microcline.
Parallel Polarized Light :
Color, — Colorl ess.
Indices of Refraction, — About the same as for balsam.
Relief — None.
Cleavage. — Perfect parallel to the base oP (001) and brachy
pinacoid oc P S (010). The cleavage cracks appear in thin sec-
tions, and never intersect at right angles, as may be the case in
orthoclase.
Pleockroism. — None.
Parallel Polarized Light, Crossed Nicols :
Double Refraction. — Not very strong.
Polarisation Colors. — A little brighter than for orthoclase.
Extinction. — As these minerals are triclinic, extinction will take
place in all sections unsymmetrically with respect to crystallo-
graphic or cleavage lines, hence, extinction angles will always be
observed.
For characteristic extinction angles measured on the cleavage
sections, see Microscopical Physiography of Rock-Making Minerals,
Rosenbusch (Iddings' translation) p. 299.
General Rules Regarding Extinction Angles. — Small extinction-
angles (under 10®) in all sections indicate oligoclase.
Large extinction- angles (over 30°) in all sections indicate anor-
thite.
Medium extinction-angles (5° to 20°) in all sections indicate
These rules apply to microlites, which are usually elongated
parallel to the brachy axis (a), as well as to crystals.
These extinction-angles are to be measured from the cleavage-
lines or the traces of the planes of composition in twin crystals.
Alteration .
Artificial. — Anorthite and labradorite, niore or less decomposed
by hydrochloric acid. Albite and oligoclase not acted on by
hydrochloric acid.
Natural [weathering). — The alteration processes are partly the
same as in orthoclase, forming kaolin, musco^ite, etc. Calcite is
more common as a side-product.
328 THE QUARTERLY,
The basic feldspars appear to decompose more easily than the
acid.
Important Diagnostic Properties : Generally without crys-
tal! ographic boundaries, lath-shaped form common in some rocks.
— Polysynthetic twinning, giving series of parallel bands. — Low
relief. — Cleavage. — Low polarization colors.
Differentiation :
{a) From Orthoclase. — By repeated twinning after the Albite
law, giving between crossed nicols a series of alternate dark and
light bands, and by polarization colors being a little brighter.
{F) From Microcline. — By common absence of the microcline
gridiron structure between crossed nicols.
Specific gravity separation by use of heavy solutions, and chemi-
cal and micro- chemical (Boricky's) tests should be used to confirm
other determinations in differentiating the members of the feldspar
group.
Usual Associates in Sections : Albite with the granitic min-
erals, and also intergrown with orthoclase and microcline. Oligo-
clase with orthoclase, quartz, hornblende, augite, biotite, etc.
Labradorite with augite, etc., does not seem to occur with ortho-
cfase and quartz. Anorthite with augite, hypersthene, chrysolite,
etc., not with quartz.
General Occurrence in Building Stones: Albite in granites
and gneisses, especially in those with high percentage of silica,
also in crystalline schists, rare in eruptive rocks. The twinning
may be absent.
Oligoclase very frequent in granites, syenites, gneisses, diorites,
etc. Twinning almost always shows, and the lamellae are narrow.
Labradorite confined more to the basic eruptive rocks and to
crystalline schists rich in amphibole and pyroxene.
Anorthite in diorites, diabases, gabbros, basalts, etc.
Economic Effect of the Feldspars in Building Stones.
Granite. — Feldspar, essential constituent with quartz and mica,
and the most important from an economic standpoint. The feld-
spar is usually orthoclase if the granite is rich in quartz and also
contains hornblende. The feldspar determines the color, appear-
ance, hardness, quality of polish and probable resistance to decay
of the granite. The color may be white, gray, flesh-colored, red,
etc., and at times may be affected by the color of the other compo-
MINERALS IN BUILDINC STONES, 329
nent minerals. Granite with large dull crystals of feldspar is not so
durable as when the crystals are small, bright and homogeneously
distributed, and very large feldspar crystals may split or chip out
during the process of cutting or polishing. The hardness and
toughness of granite for cutting and working depend on the feld-
spar and not on the quartz, which is brittle and always has a con-
stant hardness. Undecomposed, compact feldspar makes granite
hard, while decomposed or porous feldspar makes it soft for
working.
The colorless feldspar of the red Scotch granite is albite, and
the common associate of the orthoclase in the gray Scotch granite
is oligoclase.
A safe composition for granite is as follows : As few component
minerals as possible; unaltered orthoclase, as the feldspar, and no
plagioclase ; relative high percentage of silica ; absence of pyrox-
ene and large mica plates, and small percentage of light-colored
hornblende and mica, which, being free from iron, are not likely
to decompose.
Granites vary greatly in ability to resist agencies tending lo their
kaolinization and destruction, and the condition of the feldspar is
a matter of the greatest importance.
Causes of decay in granite, — A careful microscopic examination
might prove kaolinization of the feldspar, due to the solvent
action of water, to be progressing in granite in buildings ; but
this has not been definitely determined.* The cause seems to be
due rather to disintegration of the grains, which have different
coefficients of expansion, due to exposure to extremes of temper-
ature, freezing, etc.f The condition of the feldspar when sub-
jected to these mechanical forces must be considered, as it is more
liable to disintegration if already kaolinized. Examples, the ob-
elisks in London and New York.J
A case of rapid disintegration of granite, subjected to great
extremes of temperature, was noted by Helmerson, and was
thought by him to be caused by the presence of large grains of
plagioclase, which expand and contract unequally in the directions
* John C. Smock, Bull. N. V. Stale Museum^ No. lo, Vol. II., Sept., 1891.
t Thomas Egleston, Ph.D., ** Cause and Prevention of Decay in Building Stones,"
Trans. Am, Soc, C. E.^ Vol. XV., 1886.
J A. A. Julien, "Decay of Building Stones in New York City," N. Y.Acad, Set.,
Jan.- April, 1883.
330 THE QUARTERLY.
of the three crystallographic axes. Example^ the Alexander col-
umn in St. Petersburgh.* But it seems yet to be proved that
rocks rich in plagioclase decompose more rapidly than those con-
taining orthoclase.
In spite of the " maladie du granit," granite is one of the most
durable of stones, and is now much used for large buildings.
Granite " spalls " in large fires, and its fusibility depends on the
kind of feldspar it contains.
Syenite. — Feldspar essential constituent with hornblende, and
determines character in same way as in granite. White or light-
colored oligoclase is the important triclinic feldspar in Egyptian
syenite.
Gneiss. — Feldspar essential constituent as in granite. An exam-
ple of gneiss is said to exist in Philadelphia, in which the process
of kaolinization is going on, aided by mechanical disintegration,
reducing the stone to clay and sand. Paint has been used as a
preventive.
Feldspar Porphyry. — Feldspar essential constituent. When
stone is compact it takes a beautiful polish, and may be stronger
than granite. t Generally only obtained in small pieces. Decom-
position occurs, but, so far as is known, only " in situ."
Diabase, Norite, Diorite, etc. — Plagioclase essential con-
stituent, together with augite or hornblende, magnetite, etc. These
rocks are generally darker in color, not so good for beautiful
buildings and harder to quarry than granite. They may be i^sed
for paving.
Sandstone. — Large percentage of feldspathic material maybe
found in brownstone or sandstone, so much so as even to ^\v^
character to the stone and render it liable to easy decomposition,
especially if the feldspar is kaolinized. The presence of grains of
kaolinized feldspar may not always be injurious, provided the struct-
ure of the sandstone is firm and impervious to water. Example^ a
specimen of sandstone, containing kaolinized feldspar grains, from
Trinity Church, New York, showed, when examined, that the
grains had not suffered any further decomposition since the
** make-up " of the sandstone %
* Helmerson, Science , Jan. 22, 1886, p. 75.
f Rankine, Ctvj'I Engineeringj article on " Building Stones."
J Thomas Egleston, Ph.D., "Cause and Prevention of Decay in Building Stones,"
Trans. Am. Soc, C, E,, Vol. XV., 1886.
MINERALS IN BUILDING STONES. 331
CYANITE, Disthene.
Anistropic. Biaxial. Triclinic.
Composition : (AlOjj SiOg. H., 5 to 7. Sp. gr., 3.56 to 3,67.
Usual Appearance in Sections : As crystals and parallel
columnar aggregates. Crystals are blade like and elongated par-
allel to prism axis. Cross-sections show two long parallel edges,
and four shorter edges.
Twinning. — Very frequent.
Parallel Polarized Light :
Color. — Colorless to bluish. Pigment generally disseminated
irregularly. May become almost opaque on account of carbona-
ceous matter.
Index of Refraction. — Pp = 1.720 (Des Cloizeaux).
Relief, — High, and rough surface.
Cleavage, — Very perfect, parallel to macro pinacoid oc P 6c
(100), forming sharp cracks which are parallel to the longest
edges in cross-sections. Less distinct parallel to brachy pinacoid
oc P ^ (010). There is also a parting parallel to the base oP (001).
Plcochroism, — Only noticed in well colored crystals, colorless to
blue.
Parallel Polarized Light, Crossed Nicols :
Double Refraction, — Quite strong.
Polarization Colors, — Rather bright.
Extinction. — Being triclinic extinction angles are observed in
all sections, reaching a maximum of 30° to 31° on the macro
pinacoid a P ^ (100). On the base oP (001) the extinction an-
gle is very small, measured from the most perfect cleavage.
Alteration : Not attacked by acids, and weathering seldom ob-
served.
Important Diagnostic Properties : Colorless to bluish. — High
relief and rough surface. — Cleavage. — Polarization colors rather
bright. — Extinction angles always observed.
Usual Associates in Sections: Garnet, quartz, mica, horn-
blende, etc.
General Occurrence in Building Stones : Highly character-
istic of mica schists, gneisses, etc. , especially if of metamorphoric
origin.
332 THE QUARTERLY.
SERPENTINE.
Homogeneous Aggregate.
Composition : H4Mg3Si20j„ with replacement by Fe. H., 2.5
to 4. Sp. gr., 2.5 to 2.65.
Usual Appearance in Sections: Fibrous or laminated in
structure.
Parallel Polarized Light :
Color, — Greenish, bluish green or yellowish brown, often nearly
colorless.
Index of Refraction, — Low, being about the same as balsam.
Relief, — None, and smooth surface.
Inclusions, — Pieces of the undecomposed parent mineral are often
present, giving to the section a mesh-like or net-like appearance.
Pleochroism, — Very feeble.
Parallel Polarized Light, Crossed Nicols :
Double Refraction, — Rather weak.
Polarization Colors, — Pale bluish gray and neutral tints. The
aggregate structure is distinctly seen between crossed nicols.
Fine, confusedly fibrous aggregates may appear isotropic.
Alteration : Attacked quite strongly by hydrochloric acid, still
more so by sulphuric acid.
Important Diagnostic Properties : Yellowish green color. —
Faint pleochroism. — Aggregate structure between crossed nicols,
and low polarization colors.
Differentiation : From Chlorite. By aggregate structures be-
tween crossed nicols and faint pleochroism. Chlorite has com-
monly a micaceous structure and is pleochroid, although in certain
cases very feebly so.
Usual Associates in Sections : Serpentine is essentially a de-
composition product, principally from the minerals chrysolite, am-
phibole, pyroxene, etc. ; and is therefore found with these minerals
and also with the orthorhombic pyroxenes, garnet, magnetite,
chromite, chlorite, magnesite, etc.
General Occurrence in Building Stones : As a massive rock
and as the result of decomposition in rocks. It may also occur
mixed with calcite or dolomite, forming the so-called verd-antiquc
marble or ophiolite.
MINERALS IN BUILDING STONES. 333
- Economic Properties : Serpentine rock is tough, compact and
of variable color. At the same time it is soft, can be easily carved,
takes a good polish, and is very available for indoor work. It is
useless for large buildings on account of its softness ; and when it
contains calcite as an impurity is unfit for use in cities, as the cal-
cite will dissolve away, pitting the stone and dulling the polish.
When, however, it is free from impurities and bad veins, it is non-
absorbent and not affected by gaseous atmosphere. It is not
mined much outside of Pennsylvania, and it is not generally pos-
sible to get it out in large pieces.
KAOLIN, Clay.
Earthy Aggregate.
Composition: H^AlSigOg. H., 2 to 2.5. Sp. gr., 2.6 to 2.63.
Usual Appearance in Sections: Loose earthy aggregates,
formed by weathering of feldspars and other silicates.
Aggregates of kaolin are cloudy and scarcely translucent, and
no perceptible change takes place between crossed nicols.
Loose scales are transparent and colorless.
Double refraction strong.
Alteration: Insoluble in hydrochloric and nitric acids, decom-
posed by sulphuric acid.
Differentiation : From colorless Mica. When in scales is only
distinguished by proving absence of alkalies chemically.
General Occurrence in Building Stones, and Economic
Effect :
Granite, etc. — May be present as decomposition product, re-
sulting from alteration of the feldspars. It is injurious, as it ren-
ders the granite much more liable to disintegration through the
action of percolating water and frost.
Sandstone. — May be present and absorb moisture, thereby in-
creasing the rate of disintegration of the .stone.
Limestone. — May be present and has injurious effect due to
absorption of water and expansion.
Serpentine. — May be present as an impurity.
Clays and Sijvtes. — Essential constituent.
VOL. XV. — 23
334
THE QUARTERLY.
APPENDIX.
A. — The effect of the action of citric acid on the minerals found
in building stones.*
Quickly Decomposed.
Slowly Decomposed.
Very Slowly
Decomposed.
Not Decomposed.
Carbonates
Serpentine
Orthoclase
Quartz
(Calcite, Dolomite)
Pyroxene
Oligoclase
Cyanite (?)
Phosphates
Hornblende
Albite (?)
(Apatite)
Biotite
Prochlorite
Garnet
Muscovite
Chrysolite
Epidote
Tourmaline
Nephelite
Pyrite
Staurolite
Pyrrhoiite
Limonite
Hematite
Mflgnetite
These results of actual investigation are of great interest, and
illustrate very well the undoubted action of organic acids as de-
composing agents. In some cases the investigations extended
over long periods of time, even to the extent of two years.
B. — List of References consulted.
Bayley, W. S. — Summary of Progress in Mineralogy and Petrog-
raphy, 1892, pp., 53, 167. On Alteration of Minerals.
Baird, S. F. — Building Stone Collection. Proc, U. S. Nat. Mu-
seum, 1 88 1, No. 9, Appendix.
Caffall, R. M. — Preservation of Building Materials by Paraffin
as used on Obelisk. Trans. N. Y. Acad. Sci., November 25,
1885.
Dana. — A System of Mineralogy, 1892 (Wiley).
* H. Carrington Bolton, " Application of Organic Acids to the Examination of Min-
erals," (third paper). Proc, Am, Assn./or Advancement of Sci. ^WoX, XXXI., August,
1882.
MINERALS IN BUILDING STONES, 335
Egleston, Prof. T. — The Cause and Prevention of Decay of
Building Stone. Trans. Am. Soc. C. E., vol. xv., 1886.
ENCYCLOPiEDiA Britannica. — Article on Mineralogy. By M. F.
Heddle. Vol. xvi., 1883.
Frazer, p. — Mineralogical and Chemical Examination of the Obe-
lisk. Trans. Am. Inst. M. E., February, 1883.
Geikie, PROF.-^Rock Weathering as Illustrated in Edinburgh
Church Yards. Proc. Roy. Soc. of Edinburgh, Session 1879
-80, p. 518.
Greenleaf, J. L. — Building Stones, Their Properties and Classi-
fication. School of Mines Quarterly, vol. i., pp. 28, 52.
Hawes and Merrill. — Report on Building Stones of the U. S.,
and Statistics of Quarry Industry for 1880. Tenth Census
of U. S., vol. X., Washington, 1884.
Henry, Prof. J. — Mode of Testing Building Materials. Am.
Jour. Sci. [II.] vol. xxii., p. 30, 1856.
HussAK AND Smith. — The Determination of. Rock-Forming Min-
erals, 1886 (Wiley).
Johnson's Encyclopaedia. — Building Stones and Bibliography.
Article by J. S. Newberry, 1886.
Julien, a. a. — Decay of Building Stones of New York City.
N. Y. Acad. Sci., January-April', 1883.
Julien. A. A. — Article on the Obelisk as a Decayed Boulder.
Annals N. Y. Acad. Sci., vol. viii., July, 1893, Nos. 1*3.
Kemp, Prof. J. F. — Lecture Notes on Economic Geology.
Levy et Lacroix. — Les Mineraux des Roches, 1888.
Merrill, G. P. — Plan for Collection of Building and Ornamental
Stones in U. S. National Museum. U. S. National Museum,
1884, No. 25.
Merrill, G. P. — Building and Ornamental Stones (Rept. Smith.
Inst.. 1885-86. Part II., pp. 277-648), 1889, Washington.
Rankine, W. J. M. — Civil Engineering. Article on Building
Stones, 1887 (London).
RosENBUSCH. — Microscopical Physiography of the Rock-Making
Minerals. Iddings' Translation, 1889 (Wiley).
RuTLEY, F. — The Study of Rocks. Text-Books of Science, 1888
(London).
Science in Short Chapters, January 29, 1883, p. 281, On the Cor-
rosion of Building Stones.
336 THE QUARTERLY.
Smock, J. C. — Bull. N.. Y. State Mus. of Nat. Hist., No. 3, March,
188&
Smock, J. C — Building Stones in New York State. Bull. N. Y.
State Museum, vol. ii., No. 10, September, 1890.
Universal Knowledge. — 1879. Article on Building Stones.
Wadsworth, M. E. — Atmospheric Action on Sandstone. Ab-
stract in Proc. Bostoo Soc. Nat. Hist., vol. xxii.^ February 7,
1883. ^
By MALVERN VV. ILES.
The attentfon of the writer has recently been directed to this
subject by reason of a large ore shipper making claim for a larger
amount of lead ia the ore than that shown, in many cases, by the
most accurate chemical tests. As the amount of money involved
was quite large, it was decided both by the ore shipper and the
smelter to carefully investigate the matter in order to arrive at a
fair settlement. This investigation developed many facts of a sci-
entific nature, aside from the commercial aspect of the subject,
which, it is believed, will be of interest and value to the readers of
the Quarterly.
The ore in question was a galena concentrate, which had been
concentrated from the crude ore runaing from 10 to 12 per cent,
of lead up to a product running from 47 to 58 per cent, of lead.
There was a small, yet variable, amount of arsenic and antimony
in the ore.
We will first produce a tabulated statement showing' the fire
assays of the ore shipper, the chemical determination of the lead
as obtained by the Alexander method,* and also a column show-
ing the result of four differeat highly responsible assayers, having
* Colorado State School of Mines Scientific Quarterly ^Wq\, L, No. 4; also The En-
gineering and Mining Journal ^ Vol. LV., No. 13, April i, 1893; ^^^^ Furman*s
Manual Practical Assayings p. 142.
years of experience and making daily a large number of fire assays
This last-named column was derived by adding together the
result of each of the four control assayers, dividing by four, and
subtracting this amount from the percentage of lead, as shown by
careful chemical tests. This column, then, will show how much
the fire assay is below the actual contents of the or€.
f our iimpkes.
fielow
chemical. Chemital. Mine.
Per cent. Per cent. Per cent.
I, 1.67 55-00 5540
2, ..... . 1.29 54.00 54.80
3, 2.53 55.00 5520
4 • 3.'7 57 .00 56.90
5 2.17 52.80 52.70
6 1.16 49.50 48.50
7, 2.22 52.30 53.10
8, . , . . .1.32 49-5^ 50.20
9, 1.60 53.20 57,20
10, 1.60 48.40 49.00
18.73 526-70 533.00
Average, .... 1.873 52.67 53.30
We learn from the above table many highly interesting and val-
uable things, some of which I will briefly point out. The result
m
of forty careful umpires on lead by fire assay, as made by four
good, responsible assayers, give as a result an average of 1.873
per cent, lower lead than the true amount. It shows that upon
the same grade of ore the fire assay is subject to considerable va-
riation even in the hands of the same person3. It shows that the
seller of ore is likely to claim, say 53.30 per cent, lead in an ore
when there is actually only 52.67 per cent., thereby giving rise to
much trouble, delay, expense, and, not unfrequently, much un-
necessary ill-feeling. In this particular case the mine-owner was
a man of the highest integrity and honesty, and there was a dis-
position on the part of the seller and purchaser to treat each other
fairly.
In order to throw still further light upon the question of differ-
ence between the fire assay on lead and that shown by careful
chemical determination, there will be given ten more cases upon
this same ore, and practically same grade, viz. :
338 THE QUARTERLY.
Fire assay. Chemical.
Per cent. Per cent.
I, 574 58.8
2, 46.0 48.5
3, 54.7 56.0
4, 50.4 52.0
5, 44.6 47.2
6, 50.4 52.5
7» 46.0 48.6
8, 49.0 51.0
9 50.4 52.4
10, 58.0 58.8
506.9 525.8
Average, 50.69 52.58
This shows a difference of 1. 9 1 per cent, lower lead than that
shown by chemical tests.
Taking the average of the first and second series of experi-
ments, we get 1. 891 per cent, as the amount the fire assay is under
the chemical determination of the lead in a certain grade of sul-
phide ore.
It does not follow, however, that all ore will show by fire test
about 2 per cent, lower than that shown by chemical test ; yet I
will say that this is not far from the truth. The variation is, of
course, dependent upon many things, chiefly, however, upon the
nature of the impurities in an ore and the mode of assaying.
The elements which tend to make the assay high are as follows :
Antimony, arsenic, bismuth, cadmium, cobalt, copper, gold, iron,
nickel, platinum, silver, tin ; aside from these may be mentioned
carbon in the form of a carbide of iron ; pieces of slag, arsenide
of iron or speiss, and always some sulphide of potassium and so-
dium, mechanically adhering to the button even when flattened
out. The most common things which tend to produce high re-
sults are: using too powerful reducing flux, causing iron, copper,
arsenic and antimony to enter the button, and also the imperfect
separation of mechanically adherent particles. I have not unfre-
color, also pieces of iron adhering to the button, pieces of slag,
etc. The things which tend to produce low results are: fusing at
too high a temperature, keeping the crucible in the fire too long,
improper flexing, and using too low a heat. Whilst many other
things are conducive to low results yet they can be classed as
FIRE ASS A V FOR LEAD. 339
losses by volatilization, scorification and improper separation of
I feel quite certain theie are a large number of cases where the
ore seller is paid for more lead than his ore contains. In order to
ascertain the average percentage of impurities which are weighed
two weeks; I then counted out 702 buttons, rejecting two as doubt-
ful cases; these 700 buttons were then weighed upon an accurate
balance used for weighing Dore bars, giving 38.45 troy ounces,
which is equal to 1195.95 grammes; this would give an average
weight of 1.7085 grammes for each button.
Now, since 5 grammes of ore was taken in each case, then the
average percentage of the ore giving the 700 buttons was 34. 1 7
per cent. lead. During the time these 700 buttons were being
accumulated there were 400 umpires containing about 40 per cent,
lead each, and the silver contents in this ore was above the general
average. This last statement is made because it is not generally
considered that the amount of silver and gold which enters the
lead button amounts to enough for consideration, which is an en-
tirely fallacious view.
By carefully sampling these 700 buttons, and weighing out a
duplicate amount of i assay ton, it was shown that the lead buttons
gave:
3.60 ounces gold per ton of 2000 pounds.
117.90 *' silver '*
(< «(
This corresponds to :
Per cent.
Gold, 0.0123
Silver 0.4042
Total, 0.4165
That is to say, the lead buttons contained about 0.42 per cent,
impurities in the form of gold and silver alone.
In order to take an entirely fair sample of these 700 buttons, I
took a sharp pair of shears and divided each button into 10 parts,
flattening out all thick buttons to a thin sheet. These clippings,
resulting from a long and tedious operation, were then carefully
stirred up and mixed as thoroughly as possible. I then turned
this product over to the chemist, who weighed out two samples of
10 grammes each, dissolved the lead in nitric acid, and transferred
340 THE QUARTERLY.
to a litre flask, taking care to bring a small amount of sulphate of
lead into solution, dilute to litre mark, removed loo c.c. solution,
and determined the lead by the Alexander method. Our Mr. H.
H. Alexander performed all th€ chemical work in a most careful
ctnd painstaking manner by his most admirable and proven correct
method-
96.10
96.30
^ ^ I 96.20
<^.){
or an average of four determinations of 96.25 per cent. lead. This
shows the total impurities in the 700 lead buttons to be 3.75 per
cent. The first series of ten chemical determinations on different
lots of ore ran on an average of 52.67 per cent, lead; the second
series gave 52.58 per cent, lead; the average is 52.625 percent,
lead. The result of the fire assay upon these twenty lots showed
the fire assay to be 1.891 per cent, under the chemical test. By
subtracting 1.891 from 52.625 we get 50.734, or the percentage of
lead as shown by the fire assay ; but the result of an investigation
of 700 buttons showed there was 3.75 per cent, of impurities, hence
50.734 X .0375 = 1.902 or say grammes of impurities. Now by
taking 1.902 from 50.734 we get 48.832 as representing the amount
of pure lead as shown by the fire assay; hence (52.625) minus
48.832 = 3.792 or loss from volatilization and scorification, and all
other sources of loss. This would correspond to 7.20 per cent.
i.e. :
(52.625) : (3.792) : : 100 : X
X = 7.20.
The actual percentage of loss will vary with different ores, ac-
cording to the actual percentages of contained lead ; the less lead
an ore contains the higher will be the percentage of loss ; and
when the lead, as in slags, is low, say -^^ to ^^ per cent, then the
percentage of loss will often be found to be 50 to 60 per cent.
This, of course, is due to the difficulty in collecting such minute
particles.
Sufficient care is not always observed to get and maintain the
FIRE ASSA Y FOR LEAD. 341
The Denver Fire Clay Company of Denver, Colo., make up two
kinds of lead flux as follows :
S parts carbonate of potash.
6j^ parts bicarbonate of soda.
2^ parts flour.
2^ parts borax glass.
2 parts carbonate of potash.
2 parts bicarbonate of soda.
I part flour.
I part powdered borax.
The price on the No, I mixture is somewhat higher than the
No. 4. by reason of the fused borax. The borax in the No. 4 mix-
ture has been heated up in order to expel the water of crystalliza-
tion.
It is the opinion of the writer that the No. i mixture is the
better of the two cited and safer in every way. A part of the
errors and discrepancies, I think, can be traced to the difference in
the way the lead assays are fluxed.
I believe, from long observation and tests, that the Lead Flux
Mixture No. i, as prepared by the Denver Fire Clay Company, is
a good and reliable mixture, and well suited for the buyer as well
as the seller of ores.
I suppose every assayer has his certain little ** knacks " and pe-
culiarities in making an assay on lead which often he deems highly
essential for correct results. The fact of the matter is, that there
should be some standard method, and then much of the trouble
alike to the buyer as well as the seller of ore would disappear.
The best method for making lead assays, so far as my knowl-
edge extends, is that used at the Globe Smelting and Refining
Company of Denver, Colorado. This method I will give some-
what in detail, as there are features I think entirely new, but which,
from a long period of tests,* is found reliable.
The ore comes from the sampling-works department in paper
sacks, and has been thoroughly dried, powdered, and intimately
mixed, using a screen of 100 meshes.
342 THE QUARTERLY.
The ore is poured from the sacks upon a thin sheet of cloth,
covered with white rubber. The ore is then thoroughly rolled and
mixed with a large painter's spatula, flattening out to a layer of
about ^ inch in thickness. From this there is uniformly weighed
out 5 grammes of ore pulp, which is transferred directly to a Den-
ver Fire Clay Company lead cup, known as the "5-gramme cup."
The pan of the scales is flattened scoop-shape, in order to facili-
tate the introduction of the ore into the cup without any chance
of loss. The dimensions of this cup are as follows : 2^ inches
height by 2 J^ inches width at top, and has a flat bottom i J^ inches
in diameter. It holds 65 c.c, of water.
There is then placed directly upon the ore a spoonful of No. I
spoon, having the point somewhat ground off" so as to hold 15
grammes. This is then thoroughly stirred with a painter's spatula,
blade 4 inches long and 5^ inch in width at widest part. After
this thorough stirring, the crucible is gently tapped to settle down
its contents; then add directly to the top 15 more grammes of the
The crucible is again tapped gently, and there is introduced
from I to 4 tenpenny nails, with points down. For slags and
basic ores, add 3 grammes fused borax on top. There are a few
ores whose nature is such as to make it unnecessary to add any
nails, for example, the refinery litharge and certain iron fluxes
having no sulphur; also certain well-known oxidized or carbonate
ores free from sulphur. After the introduction of the nails, the
crucible is transferred directly to the muffle assay furnace, having
three muffles, each 12 inches wide by 19 inches long.
The fusion generally takes from fifteen to thirty minutes, accord-
ing to the degree of heat of the furnace, and also according to the
extent the muffle is cooled off". The moment a good quiet fusion
is obtained, the crucibles are removed from the muffle ; the nails
removed with small tongs, shaking off" any particle of lead which
may have adhered to the nails. Tap down the crucible with three
or four sharp raps upon a cast-iron plate, and pour out the entire
contents of the crucible upon the iron plate or old bucking-board;
string the slag out to a thin point ; at the extreme end, free from
slag, will be found the lead button, however small. This button
will generally be loosely adherent to the thin slag and quite easily
removed. The button is then gently hammered to free itself from
any slag or foreign substance and weighed, and as 5 grammes were
, FIRE ASSAY FOR LEAD. 343
taken, the results are doubled to obtain percentage of lead. The
appearance of the material poured out on the plate is roughly as
follows :
^uU€^g:^
Especial attention is called to the fact that a covering of salt is
entirely omitted, as it is believed it is unnecessary; and, further-
more, tending to produce results too low, due to the volatilization of
lead as a chloride. Furthermore, an earthenware cover is not used,
as was at one time thought desirable. The use of cyanide of potas-
sium, as a reducing agent, has been entirely abandoned years ago,
as the results are not reliable, as this chemical has such a powerful
reducing power as to cause copper and many other things to enter
the lead button, particularly iron, arsenic and antimony.
Regarding the use of cyanide of potassium for making lead
assays, I must positively disagree with my teacher of assaying,
who states : " the assay by cyanide gives lower results, but cleaner
buttons, and is to be recommended " (see Dr. Rickett's Notes on
Assaying, p. 61). Cyanide of potassium furthermore is not a safe
thing to use daily at large assay offices where one is often forced
to use a number of different helpers.
The breaking of the lead assay cups, or crucibles, is now an
entirely obsolete practice throughout the west.
Dr. Rickett states (p. 59), '* The lead assay is not accurate for
several reasons, chiefly because of the volatility of the lead, and
the presence of substances which alloy with the button." He
further states: "Antimony and zinc in an ore interfere with the
assay ; as the first will generally be found with the lead, while the
zinc, though partially driven off, carries lead with it." The writer
heartily agrees with these last mentioned remarks, but cannot but
feel the language should have been stronger and more explicit.
In addition to the antimony and zinc which he mentions, many
other things might have been mentioned, for example : arsenic,
copper, iron, either as metallic iron, a carbide of iron, or as an
arsenide of iron (or speiss). Also much gold or silver in the ore,
and, in short, all easily reducible elements.
344 1HE QUARTERLY.
It is my firm conviction that when one uses the best known
method to determine the lead in an ore, he is only making a blind,
rough guess, and that whilst for some metals the fire assay is a
good and useful thing, and likely to stand the test of time, yet
with lead assays by fire the whole practice should be discontinued
as an unsafe and barbarous practice. It is dangerous to the ore
purchaser, because he often pays for more lead in an ore than it
really contains; to the ore seller it must be highly unsatisfactory
and extremely annoying. No one now thinks of making a fire
assay for copper, but there is deducted from i ^ to 2 per cent,
from the chemical method to obtain the so-called " dry assay on
copper." The reason why this could not be done in the past
was largely due to the fact that there was no quick and accu-
rate method for lead. Were it not for the fact of the difficulty
of obtaining pure aluminium the method of Von Schultz & Low
would have ultimately replaced the fire-assay method in the
opinion of the writer. The method of Mr. H. H. Alexander has
met with very general favor amongst the chemists and assayers
throughout the west, and the results are remarkably good and
constant
I would suggest the use of the Alexander method in place of
the fire assay on lead, with a uniform deduction of 2 per cent, from
the results as shown by this method. I think this would be fair
both to the purchaser as well as the seller of lead ores and lead
products. I notice that Mr. Furman, in his excellent book on
Practical Assaying, gives the following composition for lead flux
mixture, viz.:
1 6 parts sodium bicarbonate.
1 6 parts potassium bicarbonate.
8 parts flour.
4 parts borax glass.
This, it will be observed, is different from that made up and sold
by the Denver Fire Clay Co. I am not prepared to state which
is the better of the two mixtures, yet this fact only illustrates the
wisdom of having some uniform standard. Mr. Furman also
states in scheme for fire assay (p. 137) there is used **^ caver of
borax ;^' this, in the majority of cases, is not necessary, but upon
all basic ores, also for slag assays, there is recommended the plac-
UTILIZING BASSASSEACHIC FALLS. 345
ing of 3 grammes of fused borax on top of the assay mixture.
For slags and iron fluxes this has been proven to be absolutely
necessary.
Berthier was the first to point out the advantages derivable by
fusing in an open crucible, since he found that such fusion of the
ore with three times its weight of sodium carbonate, the lead would
be separated in the metallic form, whilst the antimony would be-
come oxidized, uniting with the soda and remain in the slag to a
very large extent*
Dr. Hofman, in his Metallurgy of Lead gives, on page 71, no
less than nineteen different charges for making lead assays.
Whilst it is true that different ores require different treatment,
yet actual work at the large smelters show that it is not necessary
or even desirable to vary the method for making assays upon lead
products widely. Whilst I believe the only proper and final solu-
tion is to cast aside the fire assay entirely as a relic of the dark
ages, yet, until others can be brought to this belief, the next best
thing would be the calling of a general conference, and decide upon
some standard method or methods for the determinations of lead.
PROJECT FOR UTILIZING BASSASSEACHIC FALLS.
By EDWARD D. SELF.
A FEW years ago the writer visited the falls of Bassasseachic, to
measure the power produced, and report upon the practicability
of utilizing it for mining operations some miles distant. The lo-
cation of the falls, in the heart of the Sierra Madre mountains,
its great height, and the distance over which the power must be
transmitted, made the problem a unique one, for every condition,
such as head of water, irregularity of flow, character and in-
accessibility of country, were found magnified far beyond usual
proportions.
It may be interesting, therefore, to readers of the Quarterly
to briefly describe the falls, and general method of considering the
project for utilizing the power.
* See Philip's Metallurgy^ p. 532. — 1874 ed.
346 THE QUARTERLY.
On account of difficult transportation, it is necessary that no
piece of machinery should weigh over 200 or 300 pounds. The
country is so mountainous that the last 150 miles of the journey,
from Chihuahua to Bassasseachic, must be by mule-back, over a
trail in many places so steep and narrow that it is almost impas-
sable. When the falls are reached, the necessity of having alt ma-
chinery of easily manageable weight is even more evident.
The Bassasseachic river rises on the western slope of the- Sierra,
and is a tributary of the Rio Mayo. The sides of the caflon
through which it flows, are precipitous near the fall, but a short
distance back the valley widens, forming a basin which receives
the drainage of about 75 square miles. Where the sides of the
ravine are vertical, and the water is restricted to a narrow channel,
it has cut for itself curious grooves, 1 5 or 20 feet deep and a few
feet wide, in the porphyritic rock of the river bed. The erosion
by sand and gravel has produced several deep potholes near the
stream, that during the rainy season, are probably slowly deep-
ened by boulders and sand found in them. One such pothole was
doubtless formed near the top of the fall, and its partial destruction
has left a remarkable arch of rock, under which the water passes
before making its final leap.
There is no indication above the fall that a precipice is near.
The break in the bed of the stream is so smooth and sudden that
one might easily walk to the very brink without suspecting dan- *
ger. Only by leaning over the edge and looking a distance of
nearly 900 feet, can the pool at the bottom be seen. Similar walls
rise from 1 500 to 2000 feet above the bed of the stream at the bot-
tom and form the sides of the amphitheatre. The distance to the
vertical cliff on the opposite side of the ravine is about 3000 feet.
The stream below disappears in the piles of gravel and debris
through which it flows. Looking down, the task of getting safely
to the bottom seems impossible, but by retracing our steps a trail
is found leading over a knife- like spur of rock forming part of
the left side of the amphitheatre, behind which we can descend by
equal use of hands and feet. About halfway down there is a break
in the rock, behind which the trail leads, and from this opening,
called La Ventana, or window, the first and most striking view of
the fall is obtained. Looking up 400 feet, one sees the water
leaping from the cliff and falling past him to the pool over 400
feet below La Ventana. The path then passes behind the rocks
UTILIZING BASSASSEACHIC FALLS. 347
and further view of the water is lost. When at the bottom, it is
still a work of difficulty to reach the pool, for, what from above
appeared to be piles of gravel, now prove to be masses of huge
boulders difficult to surmount. The ravine below is well wooded,
and the bottom is broken by hills several hundred feet high formed
from the debris fallen from above. The bed of the stream is very
steep, so it is evident an additional head can be easily obtained by
locating the power station some distance down the canon. Such,
then, is a description of the falls whose power it is desired to
utilize.
The problem divides itself into several parts, each of which we
will consider briefly.
First, the height of the fall must be obtained. Not having a suit-
able wire by which the vertical distance could be obtained directly,
a transit and stadia rod were employed. The instrument was set up
on one of the huge piles of debris, as far as possible from the foot,
and by foresight and backsight the distances and angles were
measured. The result obtained by stadia measurement checked
very closely with the distance determined by triangulation. By
the former method, the height of the fall was found to be 871 feet.
The next step, the measurement of water flowing, was accom-
plished above the fall, to avoid error from seepage into the am-
phitheatre of water from other sources. A weir was constructed,
' and frequent measurements taken. The observations were made
at the end of a very long dry season, to ascertain the minimum
power that should be expected from the fall. At the time of my visit,
only 125 cubic feet were passing per minute. The effect of evap-
oration at high altitudes was made very evident, for measurements
taken at night or morning showed considerable variation; 125
feet, however, represents a fair average. The power which this
quantity of water will produce being less than the power required
for immediate use, the obvious expedient of storage suggests itself.
We must be able to avail ourselves of the flow of the stream dur-
ing the rainy season or times of flood, by impounding the water
by dams, and retain enough to increase the flow at the fall to the
amount desired during the dry season. The size of the dam re-
quired to do this needs careful consideration. A small dam could
be made to retain the water passing at night, which will more than
double the working capacity of the fall, provided the generating
plant runs only by day. Such a limitation in capacity is inadmis-
348 THE QUARTERLY,
sible for an important plant, so we must examine the conditions
that regulate the flow of the stream throughout the year. The first
question is to find the area drained, its topography, and the rainfall.
Unfortunately, the actual rainfall in districts where such problems
as these are found is seldom known, and the percentage of rainfall
entering the river can only be estimated. The engineer must,
therefore, make his own observations, over an extended period, or,
as is more frequently the case, content himself with a careful exam-
ination of high-water marks in the stream. Water-worn rock on
the banks, piles of drift-wood, exposed tree trunks from which the
bark is worn off, and the size of green shoots growing in or near
the stfeam, are excellent indications. If these observations check
with the tales of the '* oldest inhabitant," if there be one, an esti-
mate can often be made that is nearly as close as if obtained by
more accurate means. Having ascertained thus the approximate
maximum flood-levels, and also normal conditions of water, and
making a liberal allowance on the side of safety, we are able to
calculate the storage capacity required, and the size of waste-way
of dam. The height of the dam depends, of course, upon the re-
sult of a survey to determine the volume impounded at various
levels, and, in general, its location depends upon the situation
that gives maximum capacity for minimum cost of dam. In
high altitudes in warm climates, it is better to select a site that
will give a deep reservoir, and employ a higher, more expensive
dam if necessary. In this way, the loss by evaporation will be
reduced directly as the area of exposed water surface. For a
similar reason, one of the first steps towards securing a permanent
regular flow, especially if the stream be small, or its capacity be
doubtful, is to obtain control, if possible, of adjoining timber land,
for a well wooded water-shed may be a better reservoir than one of
earth and stone. The dam required for storing water, for the case
we are considering, requires to be of moderate height, and should
be located some distance from the fall. We find at this point that
it is better to lose the head between the dam and the intake at the
top of the falls than lay piping the entire distance from the foot of
the dam to the wheels. The complete separation of sand and gravel
is thus made simple by employing open catch-boxes over which
the water passes slowly. A calculation of the thickness of the
pipes to convey the water to the wheel shows that if it were pos-
sible to make a single pipe of sufficient strength to resist the pres-
UTILIZING BASSASSEACHIC FALLS 349
sure at the foot, and large enough to carry the water required, it
would be so heavy that it could not be delivered to the falls even
in sections. But this fact is, in itself, really an advantage, because
it prevents the possibility of committing the serious error of not
subdividing the power at the generating station into several com-
plete and independent units. The size of these units depend-
ing partly upon conditions already mentioned, is of vital import-
ance from commercial, engineering, and electrical reasons. A com-
plete discussion of this part of the subject is too long to under-
take with the space at our disposal. It is sufficient to point out
one controlling condition only. The plant should be so divided
that the failure or break-down of any part will not cause a stoppage
of the mill receiving the power ; and the arrangement of parts
must provide for future enlargement according to actual needs for
power. It should not be designed, either, solely in reference to
using the machinery built by any one builder, but should allow
the purchase of the most improved machinery that may be found
in the market, when it is desired to increase the plant.
Having determined, therefore, on using a number of small pipes,
we must look for a means of getting them down to the generating
station or power house. Two routes are open. One is through a
tunnel and down the trail on the right-hand side of the falls, as
shown in the illustration. The other is down the face of the front
of the cliff. The former is circuitous, and involves much blasting
and rock cutting, and an unknown difficulty in crossing ravines.
The latter, which is an unusual method, for an 871-foot vertical fall
has never been made captive in this way, is to bolt the pipes to the
face of the cliff. The first illustration shows a general view of the
fall and the proposed location of the pipes and the method of erect-
ing them by a suspended cradle, and the second is a larger view of
the cradle to be used for putting the pipes in place. At the bot-
tom, well out of reach of the highest floods, a suitable foundation
is required, on which steel elbows are bolted. When they are in
place, and a section of pipe secured to them, the cradle is lowered
from above until its floor is level with the tops, and other pipes are
lowered from above into place, the joints made fast, and the sec-
tions secured by straps held by anchor bolts let into the rock.
The cradle is again raised to the top of the pipe, and the next set
are lowered into position. Workmen are lowered in chairs or lifted
from the foot of the falls to the cradle by the same means. An
VOL. XV. — 24
THE QUARTkRLY.
^-^Ji
UTILIZING BASSASSEACHIC FALLS. 351
advantage of this method of erecting the pipe line, is more evident
when it is known that all supplies and machinery must be deliv-
ered at the top of the fall, and lowered in some way to the bot-
tom, for there is no road to the foot. The labor of blasting a route
down the trail would probably require the same number of drill-
holes as would be used for stay-bolts by the first method. Having
reached the amphitheatre, it is a comparatively simple task to cut
a suitable trench in which the pipes can be laid to the power-
house.
The building in which the wheels are to be located must be a
substantial structure, having channels for the tailwater so arranged
that the foundations may never be endangered by an escape of
water from the supply pipes. Besides having valves near the
wheels, other gates must be located in the sluice at the top of the
falls to divert the water from the mains. To prevent danger of
excessive strains on the resilience of the pipes if the water be sud-
denly shut off at the wheels, it is essential to keep the velocity of
flow as low as possible. This can, of course, be done by using
pipes of ample diameter in reference to the discharge nozzles, and
employing practically the same size pipe throughout.
The importance of keeping the velocity of flow small is evident
352 , THE QUARTERLY.
from the value of ^wz^, the energy developed by bringing to
rest the body of moving water. This energy must be absorbed
by the resilience of the metal composing the main or by air
chambers; or safety valves must be employed for the escape of
the water to prevent fracture or distortion of the pipe. For a
given size pipe having a thickness d-d' we have where the pres-
sure is / pounds per square inch \ )^'X/= bursting pres-
2
sure. But the value oiv varies inversely as }^7ld'''^ and the shock
varies as v.^ From which it is evident that a uniform low velocity
is desirable, and a safer construction for very high heads or dan-
gerous pressure is the employment of small-sized pipes and power
units.
The only type of water-wheel developed that can operate suc-
cessfully under a head of 1 500 feet, our total available head, is a jet
wheel. So from this class of motor we must make our selection,
taking statements of efficiency given by builders **cum grano salis."
The wheels must be covered with steel casings especially designed
to protect neighboring machinery in event of accident to nozzles,
valves or buckets. As the conditions of the problem require that
the power be made available about 1 1 miles from the falls, we turn
immediately to electricity as without a rival as a means of trans-
mitting power over long distances. The shaft of the jet wheel
should pass through suitable stuffing boxes in the wheel casing
and extend preferably through a partition into a room especially
designed for the dynamos. One or more armatures may be con-
nected to each wheel shaft.
In the electrical part of the problem we find a wide field for
demonstration of efficiencies from actual working tests. A few
observations concerning the principles involved will suffice at pres-
ent. When comparatively low voltage generators are used, the
cost of copper conductors is often the most expensive part of the
entire plant. It therefore is necessary to operate lines with a cer-
tain loss of potential. By comparing the interest on the cost of
the line and the value of the horse power lost, by heating the con-
ductor, we find that as the value of each (in the present case it is
the cost at which the power is now produced), is increased, the
less can be the allowed loss of electro- motive force between the
terminals of the line for the highest economy. We can now find
an expression covering the loss due to interest, etc., plus the loss
UTILIZING BASSASSEACHIC FALLS. 353
due to resistance, which we make equal to C, a variable. Differ-
entiating, we obtain a value V, for the loss of volts on the line
which will be theoretically most economical and which is indepen-
dent of the total electro-motive force. This gives a loss of about
3 per cent, taking a working pressure of 4500 volts. If, however,
we calculate the value of copper required allowing only 3 per cent,
drop we shall find that to transmit only 100 amperes will require an
expenditure of over $90,000, a practically prohibitory cost. This result is obtained because our formulas cannot contain terms that express the condition of the money market, but assume that un- limited capital can be had for merely asking. So we must turn to another method to determine V by assuming values and calcu- lating cost of copper until we obtain one that makes the solution a business possibility. Omitting details and calculations, cost of copper to transmit 500 horse-power 1 1 miles at 20 per cent, loss will be, for the prob- lem at hand, as follows: Volte. 1000, ;^252,ooo 2000, 63,cxx> 3000, 28,000 4000, 15,750 5000, 19,080 10,000, 2,520 Comparing the cost of copper for different losses on line using 3000 volts at motor, we can find the following: 10 15 20 25 30 per cent, loss on line.$63,000 $39,750$28,000 $21,000$16,300 cost of copper.
A comparison of these figures leads us to select as high a volt-
age as can be safely insulated and a drop of say 20 per cent, at full
tems of electrical transmission and the selection of motor, which
we must omit as it is not our purpose to touch upon the relative
merits of rival electrical apparatus in this paper. Progress in the
direction of the use of higher electro- motive force has been con-
tinuous, and the advantage of the use of high voltage is strikingly
shown by the above table. An examination, however of the chief
electrical transmission systems in actual use is the safest guide in
the selection of machinery for a new plant.
354 THE QUARTERLY,
We must now close this very general statement of an interesting
problem. If we have succeeded in suggesting to the reader the
importance of dividing engineering problems rigidly into their ele-
ments as the first step toward solution, the purpose of this paper
will be fulfilled. However formidable an undertaking may appear,
taken as a whole, it must be remembered that no problem need
ever be solved in this way. Tlie engineer who most readily analy-
zes such problems seldom sees an array of complicated unsolvable
difficulties but a series of concise questions to each of which he
can, with aufficienjt lajbor, give a definite answer.
ON. THE OCCURRENCE OF CRETACEOUS CLAYS AT
NORTHPORT, L. I.
By HEINRICH RIES.
The geological age of the extensive clay-beds on the north
shore of Long Island has been a matter of much speculation, as
the organic remains hitherto found have been few or fragmentary.
Glen Cove is the only locality where identifiable fossils (of creta-
ceous age) have been found in the clay, and while these same fos-
sils have been found along the shore as far as Lloyd's Neck,*
their condition usually tends to point to their derivation from a
distant source.
On Little Neck, in Northport Bay, is an extensive deposit of
stoneware clay and fire-sand which has been successfully worked
for a number of years. The clay is stratified, the layers being
separated by laminae of sand. In color the material varies from
black to brown and yellow, and it becomes very sandy in its upper
portion. There is a dip of 15° S.E. Overlying the clay is cross-
bedded fine sand and gravel, the latter containing much coarse
material near the surface. Very little glacial till covers the whole,
and much fine white fire-sand occurs in the bank.
In a previous paper! the writer mentioned this clay deposit, and
* A. liolUck : •* Some Further Notes on the Geology of the North Shore of I^ng
Island ^'—Trani. N, Y. Acad. Set., Vol. XIII.
t "Notes on the Clays of New York State and Their Economic Value." — Trans,
.V. y.Acati,SU,Wo\, XI.
KOSAKA MINING AND REDUCTION WORKS. 355
expressed the belief that it would be found to be of cretaceous
age. Such has proven to be the case. In a recent visit to the
locality a careful examination of the section exposed showed that
a brownish-black seam of the clay, two feet thick, contained plant
fragments in great quantity, and a few of them were sufficiently
well preserved to permit identification and prove the cretaceous
age of the deposit beyond doubt. Mr. Arthur Hollick. to whom
the material was turned over for study, has kindly given me the
following preliminary list : Paliurus integrifolia (Hollick), Laurus
angusta (Heer), Paliurus sp.,* Protceoides daphnogenoides (Heer),
Myrsine sp., Williantsonia sp., Celastrophyllum sp. Diatoms have
also been found in this clay,t £ind their occurrence is important
on account of its being the earliest recorded occurrence of these
organisms.
As fragments of sandstone containing cretaceous plants have
previously been found only on that portion of Long Island lying
to the north of a line joining the southern boundary of the creta-
ceous areas of New Jersey and Martha's Vineyard, it was sup-
posed that the cretaceous of Long Island would also be found
only within these limits. As such a line, however, passes from
Long li'land at Lloyd's Neck, this theory cannot be retained in
its present form, as the Little Neck cretaceous deposit is several
miles southeast of Lloyd's Neck.
THE KOSAKA MINING AND REDUCTION WORKS,
RICCHOO, JAPAN.
By M. KUWABARA, OSAKA, JAPAN.
Topographical and General Remarks, — The Kosaka Mining and
Reduction Works are located at the northwestern part of Ricchoo,
a province in the northern part of the Mainland of Japan. The
hills, where^the mining operations are carried on, are nearly 1000
feet above the sea level. The reduction works are situated in a
valley, a little more than a mile south of the mines.
* Resembles Paliurus Colombi (Heer), a Tertiary species (Fl. Foss. Arct. I., 122,
pi. xvii , Fig. 2d), but is much smaller. It is probably a new species
t *« Micro-Organisms in the Clays of New York State." H. Ries — 7>tf«j. N, Y,
356 THE QUARTERLY.
The locality is somewhat hilly; the hi 11- ranges generally run-
ning north and south, or parallel to the main mountain chains
traversing a few miles east of the mines. The rivers and rivulets
from different valleys of these hills form the Kosaka river, which,
passing near the reduction works, makes its way to the river
Yoneshiro ; the latter is navigable, in some seasons, to within
four miles of the works, forming a communication between the
Japan Sea and this important mining district of the province. The
Kosaka river and its upper branches are largely utilized for float-
ing logs and fuel wood from the hilly forests of the north, but they
are not high enough to be applied to the machinery of the min-
ing or the reduction works. The lowlands along the banks of
the river Kosaka are widely cultivated for rice, with scattering
villages here and there.
On the plateaus and valleys near the mines, stands a mining
office including an assay room, in the neighborhood of which the
crushing, sifting, and sorting places, and miners' houses, etc., are
regularly arranged, about a hundred and fifty in number. Around
the reduction works there is also a village, or rather a small town,
containing about two hundred and fifty houses. These two vil-
lages together contain more than two thousand inhabitants, nearly
one-half of whom are the employes of the mines and the reduc-
tion works.
No coal is found in this district, and as the transportation is not
easy, either by land or water, it cannot be imported from Hoccaido
or other coal-producing provinces of this country, so that these
works, as well as other works in the neighborhood, depend wholly
for their fuel on the forests, which are becoming quickly exhausted,
and wood is becoming dearer and dearer every year. The water-
power, too, is very limited. There are at present, two over-shot
water-wheels at the reduction works, each 20 feet in diameter and
lo feet in breadth. The one which is placed at a higWer level is
connected with the pulverizing rolls for the ore, while the other, or
the lower, is connected to the brine-pumps, blowing-engines, brick-
making machinery, workshops, etc. A third one, of nearly the
same size, may be constructed at an intermediate position between
the other two ; but the power obtainable with these three wheels
will not together exceed about 30 to 60 horse-power per d.iy of 10
hours, varying with seasons.
The maximum height of snow in winter ranges from three to
KOSAKA MINING AND REDUCTION WORKS. 357
five feet, and the average highest and lowest temperature through-
out the year is about 90° F. and 10° F., respectively. The rain-
fall is somewhat heavy, as compared with the average of the
whole islands.
The prices of manual labor in this district are low, though much
higher than the average of the whole country, as may be seen
in the following examples, viz., miners, from 38 to 18 sen,* per 8
hours; roasters, 40 to 20 sen per 12 hours; lixiviators, 38 to 18
sen per 12 hours; blacksmiths, 40 to 20 sen per 10 hours; car-
penters, 42 to 15 sen per 10 hours, etc.
Short History, — The discovery of the northern portion of the
" Kosaka Lode " was made, in the year 1829, by a peasant of a
neighboring village. The ore then discovered was the "black
ore," so called in this locality. He worked it for some time, and
tried the extraction of lead and silver from this ore with an open
Japanese hearth, but at last abandoned it as a complete failure.
In 1861, another farmer, by the name of Kobayashi, of the same
village, rediscovered the lode, but at its middle portion this time.
He was successful in extracting some silver from the recently dis-
covered ** black ore " by the same method as his predecessor. Two
years after the discovery, he built a few huts for his men in the neigh-
borhood of the mines, and continued his work, but on a very small
scale and without any profit, till the year 1866, when the governor
of this province took the work into his own hands. Mr. Oshima,
a foremost metallurgist at that time, and a resident of the province,
now built a smelting furnace of European style, and several open
hearths. This smelting furnace was the first one ever built on the
islands; but, unfortunately, it had hardly time to be set in blast
when the great civil war broke out in the next year, and thus post-
poned the work of our entire mines.
In 1870, two years after the conclusion of the civil war, the
works were taken up by the government, and the same Mr.
Oshima, having been appointed manager, recommenced his treat-
ment which consisted of the following processes :
1. Heap-roasting the "black ore."
2. Smelting the roasted " black ore " and raw " earthy ore "
(which was then discovered) in the smelting furnace, with siliceous
sand, slags, and charcoal. As soon as the molten matte formed
* One sen equal about ]4. cent.
358 THE QUARTERLY.
in the furnace, it was drawn out into the matte-pans, molten lead
was added and briskly stirred with iron tjols in order to extract
as much silver as possible from the njatte in the form of silver-
3. Heap-roasting of the partly-desilverized matte, and subse-
quent smelting of the roasted matte with plumbiferous products
in open hearths, for the production of silver-lead, and the concen-
tration of copper at the same time. These were repeated several
times, until the copper contained in the matte was recovered in
- the metallic form. The crude copper thus obtained was cast into
ingots.
4. Cupellation of silver-lead in the Japanese cupellation hearths.
The brick-silver was melted in crucibles and cast into bullion.
In 1873 Mr. C. Netto, a German mining engineer, was appointed
the chief engineer of the works. He built two large Mansfeld
smelting-furnaces, two double-hearth reverberatory roasting-fur-
naces with a 100-foot stack, and two English cupellation-fumaces.
His treatment consisted of the following processes :
1. Heap-roasting the *' black ore."
2. Smelting the roasted '* black ore" and the "earthy ore " in the
Mansfeld furnaces, and granulating the matte thus produced in
cold water.
3. Grinding the granulated matte with large stone-mills.
4. Roasting the ground matte in the reverberatories for sul-
phate of silver.
5. Ziervogel process to the roasted matte for the extraction of
silver.
6. Hunt and Douglass process to the residues of the previous
process, for the extraction of copper.
7. Refining the cement-silver in the cupellation- furnaces and
casting into bullion.
8. Melting the cement-copper in open hearths and casting in
ingots.
By this method about 70 per cent, of the silver and 30 to 50 per
cent, of the copper contained in the matte are said to have been
usually recovered. Mr. Netto left the works in 1877, and was ap-
pointed the professor of mining and metallurgy in the Imperial
University, Tokyo.
By Netto's improvements — or, rather, revolution — of the re-
duction processes, the product was trebled ; but as charcoal and
KOSAKA MINING AND REDUCTION WORKS. 359
wood, which are the only fuels in this district, became scarcer
and scarcer, and their prices higher and higher, it would have
been impossible to support the works any longer, were it not for
another great improvement in 1881. This was the abandonment
of the smelting- furnaces and the application of the Augustine pro-
cess direct to the " earthy ore,"
This improvement not only avoided the large consumption of
charcoal, but also greatly increased the capacity of the reduction
works, thus entirely altering the financial conditions of the works.
The works were bought by Ftijita & Co., in 1884, and have been
continued, with improvements, to the present day,
Geology, Form of the Ore-Deposit, etc. — The geological forma-
tipn of this district consists chiefly of a pale, green-colored tuff of
the Tertiary age. Its general strike is nearly north and south,
dipping 30° to 60" toward the east. Through the beds of tuff
and nearly along their strike, quartz-andesite outcrops at several
places, forming more or less high peaks or ranges among the wide-
spreading plateaus. The ore-deposits — of which there are sev-
eral, but only one workable — are, as a rule, found in the tuff near
the lines of contact of the two above-mentioned rocks. The only
workable one, called the " Kosaka Lode," obeys also this general
rule, and it seems (see Fig, i) to have been formed in the neigh-
borhood of the junction of andesite and tuff-beds, by means of
segregation and impregnation through the coarse breccia-like vol-
canic products forming the country rock. There is no definite
division between the foot-wall and the lode, but a most distinct
line is observable along the hanging-wall. In most parts of the
lode distinct marks of stratification can be observed, leading one
to believe them, at first sight, to be a bedded vein ; but after close
36o THE QUARTERLY.
observation it will be found that the stratification has no relation
to the mode of deposition, but is only the original marks of strati-
fication of the tuff through which the ore had afterwards impreg-
nated.
This lode runs along the strike and dip of the country-rock.
Its length, already explored, is more than 1500 feet, with the
wall to wall. In the upper portions of the lode, say 100 feet down
the outcrops, the ore is decomposed, showing an earthy appear-
ance of various shades and resembling the ** colorados " of the
Mexicans or the "pecos" of the Peruvians, but generally much
poorer. This is called the " earthy ore " in this district. The
lower parts consist of heavy black-colored ore, corresponding to
the ** negroes " of the Mexicans ; this is called the '* black ore."
The vein stuff consists chiefly of volcanic ashes, heavy spar and
gypsum. The " black ore " is composed of heavy spar, galena,
zinc-blende, copper and iron pyrites, tetrahedrite, etc., all of which
are commonly found in minute crystals and thoroughly intermixed
with each other. It is compact, hard and heavy, and no method
of concentration seems practicable. The annexed is the analysis
of an average sample of '* black ore " :
Per Cent.
Gold, 0.0003
Silver, 0.03
Copper, ............ 2.96
Zinc, '. . . . 12.26
Iron, 7.69
Tin, 0.50
Bismuth, .0.21
Antimony, ......... . o 20
Arsenic, 0.5 1
Alumina, 5.45
Lime, 1.13
Magnesia, .......... 0.64
Silica, 2.50
Sulphur, 22.02
Barium sulphate, 35' '7
Total, 99*2903
Among the minerals of which the black ore is composed tetra-
hedrite stands foremost in the richness of silver, but its occurrence
is exceedingly rare; next comes galena, the third copper pyrites,
KOSAKA MINING AND REDUCTION WORKS. 361
the fourth zinc- blende, and the fifth iron pyrites; so that the value
of a piece of blj'ck ore can be judged approximately by the pre-
dominance of one or the other of its constituent minerals. The
portions rich in galena are comparatively rare, while those rich in
iron pyrites are most abundant.
The "earthy ore" is nothing more than the decomposed "black
ore." Its value in silver can generally be told by its diflferent shades ;
the greenish and yellowish varieties are the richest, brownish, red-
ish. grayish and whitish following in order. The following is an
imperfect analysis of a richer class of the " earthy ore :"
Per cent.
Silver 0036
Copper, 0.23
Iron, . . . ' 7.41
Zinc, 2.44
Alumina,. . . . . . . . . .1.85
Silica, 27.00
Lime, . . . . , 0.50
Magnesia, 0.35
Sulphur, 2.66
Barium sulphate, 49.28
Total, 96.176
Only the '* earthy ore " is worked at present, the metallurgical
treatment of the black ore being not yet determined.
Aiming and Dressing. — As the lode can be reached by levels
from neighboring valleys to the depth of more than 2000 feet, no
shaft, hauling engine or pump is needed in mining the earthy
ore. A modification of the post and stall system of collieries is
adapted in getting the earthy ore, as the deposits were formed
not only in sitUy but widely spread out since their formation, at-
taining a breadth in some places of 700 feet, with a thickness of 5
to 50 feet, and resembling a thick bed of coal. The deposits are
commonly covered by new beds of volcanic ashes and pumice, 10
to 30 feet in depth, and where the superficial covering is not very
thick, quarrying is used for getting the ore. The earthy ore is
almost exclusively attacked with picks, very rarely needing blast-
ing. Each drift is 5 feet by 7 feet in size, and is timbered through-
out its length.
The ore from all the workings is carried out by tramways and
dumped on a platform near the entrance of the main level, where
362
THE QUARTERLY.
big pieces are picked off, and the rest is thrown down to the bin
of a trommel placed below the platform and worked by two boys.
The trommel is 2 feet in dinmeter, 4 feet in length, with 8-mesh
wire-cloth. The fine pieces passing the screen fall through an in-
clined shoot into cars which carry them to another and lower shoot,
whence they are carried to a storing place. The large pieces which
did not pass the screen also run down an adjacent shoot into other
Fig. 2.
cars, which carry them to a different shoot, whence they are carried
to a cobbing place, and after being cobbed are finished with 2-mesh
hand-sieves. The big pieces put aside at the platform are spalled
and afterward brought to the same cobbing place. The cobbing
is performed with peculiar broad-faced cobbing-hammers by women
or by the weaker men, each cobbing 200 to 500 pounds per day,
and getting three sen per roo pounds.
As no water-power is obtainable in the mines and fuel is very
difficult to be brought up, all work necessarily is performed by
KOSAKA MINING AND REDUCTION WORKS. 363
manual labor. Three sets of hand-rolls were recently adapted for
the cobbing with a good success, each set, worked by two young
workmen, crushing i J^ tons per day. All sorts of earthy ore are
mixed so as to form a single quality, and carried down by tram-
ways to the drying- furnace situated above the pulverizing-mill.
The metallurgical treatment of earthy ore involves:
I. Drying and Pulverizing, — The ore, being always wet, must be
dried before pulverizing. This is done with a step furnace (Fig. 2)
4 feet square and about 30 feet high. The ore is fed in showers
from the top by a workman with a shovel and is received by iron
Fig. 3.
5*>
Sc«K«ii«l PUtj
cars at the bottom and carried to the bins of the pulverizing rolls.
A feeder, a stoker and a carman are employed in the furnace per
shift of 12 hours, and about 100 tons of ore are dried per 24 hours,
using 3 cords of wood.
The pulverizing is performed by two sets of Cornish rolls, 18
inches in diameter and 18 inches in length, worked by an over-
shot water-wheel, 20 feet in diameter and 10 feet in width, and
delivering 8 to 20 horse-power. The dried ore is charged with
a shovel on a flat percussion sieve, and the part which does not
pass through the sieve falls on the rolls. The rolls are only
worked during the day, the two sets together producing about
364 ' THE QUARTERLY.
100 tons of pulverized ore per day. The punched screen of the
sieve has 4 holes to the linear inch. The roll-tires are cast of
white-iron, and renewed once every month. The pulverized ore is
carried in cars to the top of the roasting furnaces, a distance of
nearly half a mile.
2. Roasting. — This is done with long 3-hearth reverberatory
calciners (Fig. 3), of which there are two in constant work and one
is in reserve. Each hearth of the furnace is 9 feet by 12 feet,
and the fire-place is 2 feet by 9 feet, the stack common to the three
furnaces being 100 feet in height. A charge consists of 1700 pounds
of ore, with 4 per cent, of salt and some iron-pyrites, which is
charged on the hearth furthest from the fire-place. The ore is
kept in each hearth, with frequent stirring, during 20 minutes, and
removed to the next hearth, taking an hour to finish each charge.
The first, or finishing hearth, is kept at a cherry-red heat, but the
third, or hearth furthest back, is almost dark. Each furnace needs
two shifts of 6 roasters and i assistant each, and roasts 60 charges,
or 102,000 pounds of ore, per 24 hours, using 4 cords or thereabouts
of wood. The roasted ore is received from the finishing hearth in
iron cars and carried to the cooling floor, where it is left by itself
for some hours, and lastly sprinkled with cold water.
About 7 per cent, of silver originally contained in the ore is
lost in the roasting, while about 75 per cent, of the remainder is
converted into chloride. The work of the cooling floor and that
of carrying and charging the cooled ore to the dissolving vats is
performed by contractors at 72 sen per ton.
3. Lixiviation arid ' Precipitation, — These operations are per-
formed as in the Augustine process. There are 21 dissolving vats
placed in a straight line on the highest floor, next to that of the
storage-tanks, of the lixiviation room. The vats are elliptical in
shape, measuring 7 feet in length, 5 feet in breadth and 2^ feet in
depth, holding 2 tons of roasted ore. A much larger size of vats
is desirable, but the size of the room does not permit it. Over
the false-bottom of the vat, perforated with i-inch holes, two
sheets of straw-matting are laid, and fixed against the sides of the
vat by means of a temporary wooden hoop. The ore is charged
on the filter bottom thus formed to within 6 inches of the rim of
the vat, but it shrinks many inches after the introduction of hot
brine. Base metal leaching with water does not precede the lixi-
viation with brine. The brine is introduced over the top of ore
KOSAKA MINING AND REDUCTION WORKS. 365
through a wooden trough, which runs along the discharging side of
the row of dissolving vats, and receives the brine from the storage
tanks placed on the highest floor at one end of the room. The
brine contains about 18 per cent, of common salt and large quan-
tities of chloride of iron. Its temperature is generally kept at
70° C. The current of the brine is broken by a piece of matting
floating in the vat.
It takes about 10^ hours to complete the lixiviation of a vat of
ore, 41 cubic feet, or 20^ cubic feet per ton of ore, of brine being
usually needed. When no trace of silver is detected in the solution
by a polished copper plate held at the discharging cock of the vat,
the flow of brine is cut off", and wash-water is turned on in its
Fig. 4.
'^
place, from a much smaller trough placed adjacent to that of brine,
to take out the brine remaining in the tails as completely as pos-
sible. The washing with water continues about one hour, and
the tails are taken out with wooden shovels to the wagons on the
tramway along the charging side of the vats, and carried to the
dump-heap, a distance of about a quarter of a mile. The precipi-
tation tanks, Fig. 4, are built wholly of bricks, lined with the Port-
land cement inside. The first or highest tank is only for the settle-
ment of some fine slimes and ferruginous matter contained in the
solution coming out of the vats. The second and third are for
precipitating the silver by means of copper. These have a false
bottom formed just like that of the dissolving vats. Over the false
bottom covered with straw-matting, a bed of bean- shot copper,
about 2 inches thick, is laid, which, in turn, is covered with double
layers of sheet-copper, after the manner of setting tiles on the roof,
each sheet being 8 inches x 6 inches and i inch thick. On the
VOL. XV.— 25
366 THE QUARTERLY.
top of the sheet-copper beds in the second tank, wooden frames
resembling those of a window, are placed, over which double layers
of matting are laid, to form a filtering bottom. This is important
for separating the thick ferruginous deposits which will, other-
wise, be mingled with the cement-silver deposited below them.
The fourth or lowest tank is for precipitating the copper by
means of iron, the iron used being old pcraps from iron-works.
The brine escaping the fourth tank flows down to the brine-sump,
whence it is constantly pumped back to the storage-tanks, by
means of five wooden pumps worked by a water-wheel. The
brine is warmed to the proper degree in the storage tanks by
means of steam, and lasts indefinitely, salt being added, from time
to time, in the brine-sump. This addition of salt amounts to a
ton per day, or nearly 19.6 pounds per ton of ore. A boiler of 20
nominal horse-power furnishes the steam here used, and consumes
a little more than 2 cords of wood per day.
Each of the precipitation tanks, 125 feet in length, is divided
into eight equal compartments, independent of one another, so
that any compartment can be emptied without interfering with
the work of the other compartments. The cement-silver is taken
out once every month and squeezed to circular disks, I foot
in diameter and nearly 33^ inches thick, by means of a screw-
press. The cement-silver, when dried, contains from 15 to 75
per cent, of silver. The cement-copper is taken out from two
compartments, alternately, every day, fresh scrap-iron being added
each time. The cement-copper contains about 70 per cent, of
copper and 0.15 per cent, of silver. About 80 per cent, of silver
and 60 per cent, of copper are usually extracted from the roasted
ore, the residues holding about 0005 percent, of silver.
Two shifts of 8 men each, are needed in the lixiviation works
every 12 hours ; 5 at the vats and tanks, i at the pumps, and 2 at
the boiler. The residues from the dissolving vats are removed
by contractors at a cost of 48 sen per ton.
4. Refining the Cement-Silver, — The disks of cement-silver are
dried in retort dryers, and subsequently refined with an addition
of lead, in the two English cupellation furnaces. The tests are
made of the best hydraulic cement, with no addition of sand ;
125 pounds to 170 pounds of cement-silver make the charge
for a campaign of cupellation, and the lead to be added to a
KOSAKA MINING AND REDUCTION WORKS. 367
to finish a campaign, and a test lasts for three successive campaigns.
The silver, after refining, is poured into water, while still in the
molten state, for granulation. The granulated silver is melted in
graphite crucibles and cast in cast-iron moulds. A brick of the
bullion measures 12 inches long and 3.4 inches wide at the top,
14 inches long and 5.4 inches wide at the bottom, and nearly 4.2
inches thick, weighing, on an average, 1000 ounces. Their aver-
age fineness is 985. They are sent to the mint, at Osaka, to be
cast into coins.
5. Treatment of the Cement- Copper, — It is melted in small open
hearths with charcoal, with some addition of quartz-sand and
lime, and after skimming the slag thus formed the molten copper
is cast into ingots. Half a ton of cement-copper is melted in a
hearth per day, a smelter and an assistant, and a little more than
400 pounds of charcoal, being needed. The size of an ingot is 17
inches by 7 inches, and I inch in thickness, weighing 50 to 60
pounds. It is above 80 per cent, fine and is sold as argentiferous
ingot-copper. A part of the cement-copper, however, is further
refined for the manufacture of the copper-plates and shots to be
used in the precipitation tanks.
Yield of the Reduction Works, — For the year ending September
30, 1 891, the results obtained in the reduction works were as
follows :
Quantity.
Ore treated, . . . 32,181.8 tons.
Bullion produced, . 214,014.3 ozs.
Ingot-copper produced, 88.72 tons.
Thus, the yield of silver was 78.59 per cent., and that of copper
70.43 per cent.
Cost of Treatment. — The mining and reduction expenses for the
same year were as follows :
Exploration,
Silver contents.
269,515 5 OZS.
211,809.0 ozs.
Not calculated.
Copper contents.
1 17.14 tons.
82.50 tons.
Boring, . . . .
Quarrying,
Underground exploration,
Repairing of levels,
Tramways,
Yen, Per ton.
126.228
1,106.243
9.577.078
4,752.029
953-007
16,514.585 0.455
Mini7ig and Sorting,
Mining, 32,039.014
Sorting, 6,054.650
38,093.664 1.049
368 THE QUARTERLY.
Reduction,
Yen. Per ton.
Drying and pulverizing, 7,804.558
Roasting, 39,466.832
Lixiviation, 20,451.640
Refining, casting, etc., of cement- copper, . . 5,206.585
Copellation of cement-silver and silver lead (the lat-
ter being produced in refining cement- copper), . 2,915.424
Bullion casting, 155.160
76,000.199 2.362
Suggestions for a Treatment of Seventy Tons of the
"Black Ore" Per Day.
1. Spalliftg. — The ore coming out of mines is mostly in large
lumps. The lumps are to be spalled by spalling-hammers, some
gangues and poor portions being picked off at the same time. As
manual labor is very cheap, while both fuel and water-power are
very scarce, it is profitable to use this and the next method instead
of breakers.
2. Cobbifig. — The spalled ore, which is 6 to 4 inches in average
size, is to be broken to about i-inch size. This can be done by
women, or weak men, with cobbing-hammers. A woman of
average strength is able to cob about 1250 pounds of ore, getting
1 2 sen per day, and for cobbing 70 tons of ore per day there
must be some 150 workmen.
3. Stall-Roastmg of the Cobbed Ore. — This is to be done in the
stalls shown in Fig. 5. Each stall is 6 feet wide, 10 feet long, 3^
feet and 2^ feet deep in the front and the back wall respectively,
so that the bottom is ascending towards the back wall in the ratio,
I : 10. There are two parallel air- ways beneath the bottom cov-
ered with perforated cast-iron plates. These air-ways are for the
introduction of air to the interior of the ore-heaps during the oper-
ation, the air being regulated with bricks at the entrance holes.
About two- fifths of a cord of wood is spread regularly over the
bottom of the stall, and 8 tons of ore are piled on the wood floor
thus formed. The fire is set from the entrance holes at the front
wall, two short temporary chimneys of slabs being built at the
back wall. The ore is roasted twice in this manner, the first and
the second roasting taking about nine and seven days respec-
tively. A battery of about 240 stalls is wanted for roasting 70
tons of ore per day. This preliminary roasting is unavoidable,
for the roasted ore is much easier to pulverize and reduces the
KOSAKA MINING AND REDUCTION WORKS. 369
time necessary for the chloridizing- roasting nearly one-half, as
compared with the raw ore.
4. Pulverizing the Roasted Ore. — This is to be done by three
sets of 26 inch Krom rolls, two sets of which being each con-
nected to a water-wheel and devoted to coarse crushing, while
the third is worked by a steam-engine and adapted to fine crush-
ing. Each of the water-wheels exerts about 12 horse-power for
ten hours per day, while the steam-engine is 40 horse-power and
works through day and night. The coarse-crushed ore is sifted
through a i6-niesh sieve previous to the fine-crushing, that part
which passes the sieve being estimated at about 50 per cent, of the
total amount. With these arrangements it will be able to crush
70 tons of ore per day so as to pass the i6-mesh sieves.
g. Chloridizing-Roasting of the Pulveri::ed Ore — The roasting is
to be done in long reverberatory calciners, just like those used in
the treatment of the earthy ore, but having four hearths instead of
three. A charge consists of ^ ton of ore and 4 per cent, of com-
mon salt. The ore is kept one hour and a half in each hearth,
thus taking six hours to pass the four hearths. The salt is added
in the last hearth an hour before its discharge. Six of such fur-
naces are needed for roasting 70 tons of ore, each furnace roasting
14 charges per day. The finished ore is received by iron cars and
conveyed into the cooling floor, where it is to be kept for several
hours, and finally sprinkled with water.
370 THE QUARTERLY.
6. Treatment of the Chloridized Ore by the Augustine Process, and
Subsequently by the Kiss Process, — The dissolving-vats, precipita-
tion-tanks, etc., for the Augustine process, are exactly the same as
those used in the case of the earthy ore. The lixiviation with a
hot saturated brine is continued for eleven hours and is then leached
with water so as to remove the remaining brine. The silver and
copper are precipitated with copper and iron respectively in the
same manner as in the case referred to, the cement-silver being
taken out and formed into disks once a month, while the cement-
copper is to be cleaned out from two compartments of the tank,
alternately every day.
After leaching the residues of the foregoing process with water
for an hour, lixiviation with a cold 2 per cent, solution of calcium
hyposulphite is commenced and continued about twenty-two
hours. The residues are then washed with water for an hour and
carried off by cars to the dump-heap, as sluicing is not practica-
ble. The argentiferous liquid running out of the vats is con-
ducted to large precipitation-tubs, placed in a row in the neigh-
borhood of the precipitation- tanks of the preceding process. Each
of these tubs is 7 feet in diameter and 7 feet in depth. The silver
is precipitated from the liquid in the precipitation tubs with cal-
cium sulphide, the clear solution above the settled precipitates
is to be run into a sump, and pumped back to the storage-
tanks. The precipitates are to be cleaned out from every tub once
a week, and boiled with caustic soda or lime for saving the
free sulphur contained in them. The sodium or calcium sulphide
solution is siphoned out and used for precipitating fresh charges,
while the residual sulphides are to be thoroughly washed with
water and squeezed into disks by means of a screw-press or a filter-
press, such as Johnson's.
About seven-tenths of the silver extractable in these processes
will go into the cement-silver, one-tenth to the cement-copper and
the remaining one-fifth to the sulphides. The cement-silver usually
contains 40 per cent, of silver, and the cement copper o.li per
cent, of silver and 65 per cent, of copper, while the sulphides,
whose composition is very variable, contain something like 0.56
per cent, of silver, 35 per cent, of lead, 20 percent, of copper, and
some gold, which amounts to about 0.5 per cent, of the silver con-
tained in them. Now, assuming the yield of silver as 80 per cent.
KOSAKA MINING AND REDUCTION WORKS. 371
of its original amount in the ore, and that of copper 50 per cent.,
there will be formed about 860 ounces of cement-silver, 1200
pounds of sulphides, and 3000 pounds of cement-copper, from 70
tons of ore.
The two different lixiviations are applied to this ore in order to
obtain, by the Augustine process, as much silver as can be ex-
tracted in the metallic state, and the greater portion of the copper
at the same time ; and by the Kiss process to extract the silver
and gold which would not be recovered by the former process.
The precipitates from the Kiss process are very troublesome to
handle, and a large loss of silver may occur ; but much of this
can be avoided by the introduction of the Augustine process as
here suggested.
7. Roasting the Sulphides. — This is to be done in a small muffle-
furnace, the sulphurous acid gas generated in the furnace being
utilized for the manufacture of calcium hyposulphite. The sul-
phides will lose about 20 per cent, of their weight by roasting ;
so that 960 pounds of roasted products will be obtained by roast-
ing 1200 pounds of raw sulphides.
8. Reduction of the Roasted Sulphides. — For this purpose the
roasted sulphides are to be formed into balls, about 3 inches in
diameter, with some addition of clay. These balls are to be melted
in a small smelting- furnace, with some fluxes and charcoal, the
products being cupriferous silver-lead and some matte. The matte
must be roasted in a stall or a kiln and again added to the furnace.
from 960 pounds of roasted sulphides.
9. Liquation of the Cupriferous Silver- Lead. — For separating the
copper and lead in the cupriferous silver-lead, it is to be liquated
in the Japanese liquation-furnaces, the products being silver-lead
and crude copper. From 620 pounds of cupriferous silver-lead
copper will be formed, the silver-lead containing 2 per cent., or
10. Treatment of the Cement Copper and the Crude Copper. — The
cement-copper and the crude copper from the last operation are
melted in open-hearths and cast in iron moulds, in exactly the
same way as in the case of the cement-copper obtained from the
earthy ore. From 3000 pounds of the cement-copper, about 2400
372 THE QUARTERLY.
pounds of the ingot-copper, of about 80 per cent, in fineness, will
be produced.
11. Manufacture of Copper^Plates and Bean-Shot Copper. —
Besides the cement- copper, there will be produced about 1000
pounds of cement-copper per day from the copper plates and shots
placed in precipitation-tanks. This quantity of copper must be
refined by melting it with plumbiferous products in open-hearths
and liquating the alloy thus formed in Japanese liquation- fur-
naces, the products being silver-lead and crude copper; the latter
contains about 92 per cent, of copper and is cast into plates and
shots to be again added to the precipitation-tanks. On treating
and 700 pounds of plates and shots will be produced.
12. Cupellation of the Silver- Leads from the Prei^ious Opera-
tions, — This is to be done in the English cupellation-furnaces,
cupelling 10,000 pounds of silver-lead in a campaign lasting
four days. The products are auriferous brick-silver, litharge, and
hearth-bottom. From 467 pounds of silver-leads obtainable per
70 tons of ore, about 109 ounces of auriferous brick-silver will be
produced.
13. Refining the Cement-Silver. — This is to be cupelled in the
English cupellation-furnaces, exactly as in the case of the similar
substance from the earthy ore. From 860 ounces of cement-
silver, about 350 ounces of brick-silver will be obtained.
14. Casting the Brick-Silver. — The common and auriferous
brick-silvers are to be separately melted in graphite crucibles, and
cast in iron moulds well smoked with a piece of burning rosin.
From 109 ounces of auriferous brick-silver and 350 ounces of
common brick-silver, about 107.43 ounces and 346.00 ounces of
auriferous and non-auriferous bullions will be produced respec-
tively.
15. Reduction of Litharge and Hearth Bottom, — Some of the
products from the cupellation furnaces are used in the eleventh
operation, but most of them are to be smelted in the same smelting
furnace used in smelting the roasted sulphides, with an addition
of acidic slags, and the lead thus reduced cast into bars. Some
of this is to be used in the refining of cement- silver, and the rest is
sent to markets. From 70 tons of ore, some 300 pounds of lead
will be produced.
KOSAKA MINING AND REDUCTION WORKS. 373
Estimated Product from 70 Tons of Ore.
107.43 ounces of auriferous bullion, containing 2.43 ounces of
gold, 97.39 ounces of silver, 985 fine, .....
346.00 ounces of silver bullion, containing 340 88 ounces of
silver 985 fine, («) 1.22 yen,
2666 pounds of argentiferous ingot-copper, containing 80 per
cent, of copi->er and 0.12 per cent, of silver, (a- y. 0.12,
300 pounds of bar-lead, @ y. 0.04,
Yen.*
180.48
422.58
319.92
12.00
934.98
Estimated Daily Cost of Treating 70 Tons of Ore.
1-2. Mining.
Yen.
Surveying, .... .... 0.30
Exploration, ....... 65.00
Mining, ' . . 144.00
Spalling and cobbing, 25.00
3. Stall-Roasting.
Contract on roasting @, y. 0.24 per ton,
10 wood conveyers @, y. o 30,
6 cords wood @ y. 3.10,
Tools, repairs, etc.,
Sundries, .
4^. Coarse- Crushing.
4 feeders @ 0.30,
2 men on rolls and sieves @ 0.30,
2 oilers @ 0.30, .
8 carmen @ 0.25,
I helper @ 0.18, .
Repairs,
Tools, ....
Sundries,
4^. Fine- Crushing.
4 feeders @ 0.30, ....
2 oilers @- 0.30, ....
4 carmen @ 0.22,
I helper (a 0.18, .
6 stokers (n), 0.25, ....
Wood conveyers @ 0.06 per cord,
5 cords wood @ 3.io» •
Sundries, repairs, etc., .
25.16
Per Ton.
234.30
3.35
Yen.
16.80
Per Ton.
2.10
18.60
1.60
2.50
41.60
0.59
Yen.
Per Ton.
1.20
0.60
0.60
2.00
0.18
2.00
1. 00
2.00
9.58
0.14
Yen.
Per Ton.
1.20
0.60
0.88
0.18
1.50
0.30
15.50
5.00
0.36
* April, 1894, one silver yen equal 50.1 cents; one gold yen equal 99.7 cents.
374
THE QUARTERLY.
5. CMoridising-Roasting.
Y<:n.
8 feeders @ 0.27, .
• • • « a
2.16
72 men on furnaces @
.30 to 0.40,
. 23.40
I helper @ 0.27, .
• • • •
0.27
Wood conveyers @ 0.06
per cord,
1.08
18 cords wood @ 3.10,.
• • fl «
55.80
2.8 tons salt @ 17.43, .
• • • t
48.80
Tools, repairs, etc.,
* • 4
3.00
Sundries,
• • • • •
5.00
Per Ton.
@ 0.06 per ton
I39.5«
6. Lixiviation and Precipitation,
Contract on cooling and charging @ 0.08 per ton,
15 lixiviators @ 0.32 to 0.38,
4 men on pumps @ 0.30,
3 men on preparing chemicals @' 0.25, .
5 men en precipitates @, 0.25,
7 men on cement copper @ 0.22, .
j^^ man on cement-silver squeezing @« 0.22,
% man on cement-silver @ 0.22, .
2 general assistants @ 0.20,
I office helper (a) 0.20,.
Contract on carrying residues
I ton scrap-iron @ 40.00,
^ t<m sulphur @ 15.00,
^i ton lime @ 12.00, .
Sundries,
Tools, repairs, etc..
Steam,.
7. Roasting 1200 pounds of sulphides from Kiss
process,
8. Reduction of 960 pounds of roasted .sulphides, .
9. Lixiviation of 620 pounds of cupriferous silver
10. Melting 3000 pounds of cement-copper and 266
pounds of crude copper, ....
11. Refining looo pounds of cement-copper, .
12. Cupel iation of 467 pounds of silver leads from
ninth and eleventh operations,
13. Refining 860 ounces of cement-silver,
14. Casting 109 ounces of auriferous and 350 ounces
of non-auriferous brick-silvers,
15. Reduction of plumbiferous products for 300
1.44
0.34
0.73
586.96
1.99
Yen.
Per To
5.60
4.98
1.20
0.75
1.25
1.54
0.07
0.15
0.40
0.20
4.20
40.00
13.92
3.75
3.00
7.50
5.00
12.00
105.51
I.5I
5.67
0.08
1.84
0.03
0.02
9.99
0.14
7.82
O.II
2.32
0.03
I.I5
0.02
0.00
0.01
8.39
ABSTRACTS.
Analytical Chemistry, by E. Waller, Ph.D.
Action of Acids an Glass. Foerster {Fres. Zts, Anal. Chem.^ xxxi i i., 299).
1. The attack of glass by aqueous solutions of acid is not essentially
dependent on the kind, and within certain limits, the concentration of
the acids.
2. The attack on glass by aqueous solutions of acids only results from
the water contained in them.
3. The co-operation of the dissolved acids consists simply in neutral-
izing the alkali passing into s61ution.
4. Aqueous acid solutions attack glass more weakly than does pure
water ; also,
5. Glasses rich in lime, as well as flint-glasses containing much lead,
undergo strong attack by aqueous solutions of acid, which attack is de-
pendent on the kind and concentration of the acid solutions.
6. Boilijig sulphuric acid acts more weakly upon ordinary lime-glasses
than does boiling water.
7. Sulphuric-acid fumes attack glass strongly at high temperatures,
since coatings of alkaline sulphates form, and exert a profound altera-
tion of the surface of the glass.
Researches on the superficial clouding of the surfaces of glass (Ver-
witterung, /A, p. 322), lead to the conclusion that the phenomenon is
chiefly due to water of composition in the glass. Some lime-glasses are
hygroscopic and cloud up more quickly.
Filter Paper, Cramer {Zts. Aug, Chem.^ 1894, 269) recommends the
use of filter papers partially, or entirely, composed of nitrocellulose.
Such paper filters more quickly than ordinary paper, as the nitrocellu-
lose has less tendency to felt together ; it is less hygroscopic, and is, of
course, quickly incinerated.
Volatilization of Salts during Evaporation. Bailey {J. Lond. Chem.
Soc,^ Ixv., 445) communicates a preliminary note of this subject. The
experiments were conducted chiefly with alkaline chloride solutions.
The loss, in many cases, was quite perceptible, and suggests a hitherto
unsuspected source of error in some determinations.
Ammonia by Nessler Reagent. De Koninck {Chem. News^ Ixix., 220).
The assertion that alcohol in a solution diminishes the sensitiveness of
the Nessler test having been questioned, a series of experiments are
recorded which confirm that assertion. The presence of one-sixth of
alcohol modifies the appearance of the precipitate perceptibly. Bohlig^s
test (with HgClj) is unaffected by alcohol.
Free Acids in Salts of the Heavy Metals. Hoffmann (^Chem. Zeit.^
xvii., 13 18). The base is precipitated by a slight excess of K^FeCyg,
and the free acid is then titrated in an aliquot portion of the clear solu-
tion with N/10 soda, using phenolphthalein as indicator. The metals
should be in the highest state of oxidation ; e.g., the method is inap-
plicable with FqSO^.
376 THE QUARTERLY.
Volumetric for Barium. Soltsien {Phann. Ztg., xxxv., 372). The
solution must be neutral, or, at most, contain only a trace of acetic
acid. A standard solution of KjjCrO^ is then run in until a drop of the
solution on a porcelain plate just begins to give a blue-black with a drop
of haeraatoxylin solution.
Iron in Ores, Mixer and Dubets {^Eng, and Min. J.^ Ivii., 342). A
rapid method in use in the Lake Superior region is described. It con-
sists in dissolving the ore directly in acid SnCl^ solution, and titrating
with standard permanganate.
The solutions used are: Standard permanganate, i c.c. = o.oio
gramme FerSnCl^ solution ; i pound SnCljin i pound cone. HCl, diluted
to 2 litres ; ** titrating solution,*' 160 grammes MnSO, in 1750 c.c. water,
to which is then added 330 c.c. phosphoric acid and 320 c.c. H^SO^ ;
saturated solution of HgClj. 0.5 gramme or less of the pulverized ore
is treated in a beaker with 2.5 c.c. of the SnCl, solution; then 10 to 15
c.c. of HCl (1:1) are added, the beaker covered, and the solution is
boiled until the ore is completely dissolved. This requires * to 5 min-
utes. While the solution is still hot, more SnCl, solution is added, drop
by drop, until the yellow color of Fe,Clj just disappears. Then 5 c.c.
of the HgClj solution are added to remove the excess of SnCl^. The
solution is then poured into a 500 c.c. beaker, diluted, and 5 to 10 c.c.
of the ** titrating solution '* added. Titrate immediately with the stand-
ard permanganate.
It is regarded as safer to keep on hand a standard ore, which is dis-
solved and titrated with each set of analyses, to check against any pos-
sible errors due to changes in the solutions.
Separating Titanium from Iron, Baskerville (y. Am, Chem. Soe,,
xvi., 427). It is found that if a neutralized solution of TiCl^ and Fe^Cl,
not too dilute is boiled with an excess of SO^, a complete separation is
Analysis of Commercial Nickels, Fleitmann (^Fres, Zts, Anal, Chem.^
xxxiii., 335). Dissolve 5 grammes in aqua regia and evaporate repeatedly
with HCl to convert to chlorides, and filter off C and SiOj. To the
sufficient to precipitate only the Fe ; add a drop of acetic, boil and fil-
ter. Dissolve the precipitate in HCl, and precipitate with ammonia. If
any Cu has adhered to the precipitate, reserve it to be added to the re-
mainder of the Cu when obtained. After separating Fe from the main
solution, add a drop of HCl, and then gradually H^S solution, until all
Cu is precipitated, a point easily detected. Avoid carefully an excess
of H^S. After filtering off the Cu, pass H^S in the cold to separate
ZnS ; filter off the ZnS. Boil H^S out of the filtrate, neutralize, warm
to 60-80° C, and then add gradually a weakly alkaline solution of
NaClO. All Mn precipitates as brown MnO,, then Co as blackish
brown Co^O,, and finally Ni as deep black Ni^O,. The beginning of
the precipitation of the last is marked by a noticeable evolution of O,
as well as by the change in color. Boil and filter. When managed
with care, by stopping at the right point, but little Ni will remain in
the precipitate. Dissolve in hot HCl, heat to expel CI, convert 10
ABSTRACTS. m
acetic solution ; precipitate all three by passing H,S. Dissolve in
HNOj, separate Co by KNO,, and determine Mn in the filtrate.
Phosphor Tin. Lobry de Bruyn {^Rec, Trav. Chim,^ xii., 262). About
I gramme of the alloy in small pieces is weighed out in a small flask.
40-50 c.c. of water is added, and, after placing the flask in cold water
(i c.c. or less at a time). Care must be exercised to keep the tempera-
ture down as much as possible, and sufficient Br must be added to effect
complete decomposition. Rinse with cone. HCl into a porcelain cap-
sule, and heat until all free Br is expelled. Dilute, separate Sn by H,S,
and in the filtrate determine P by magnesia mixture.
Phosphor Tin, Teed (A^afysfyXix., 133). The method recommended
is to oxidize with HNO,; destroy the HNO, by evaporation with
NH^Cl ; render alkaline with ammonia, and warm with excess of
(NH J,S. Metals of the lead group may here be filtered off, and from
the solution the SnS^ is separated by acidifying. In the filtrate, P^O^
may be determined by magnesia mixture. In the discussion, Dr. Dyer
said the method failed to give SnS, free from P^O^. His method was :
Dissolving in HNO,, then adding very little HCl, only enough to keep
Sn in solution, and then precipitating out P,Oj by molybdate.
Electrolytic Separations, Smith and Spencer (y. Am, Chem, Soc^w'x,^
420) Ag and Cu. Classen's method for separating these metals by pre-
cipitating out the Ag as oxalate, and then electrolyzing separately, was
found to be inaccurate, some Ag being always found with the Cu. By
use of KCy solution at 60 to 65° a perfect separation was effected. Ag
only, deposited. Jig and Cu; satisfactory, in KCy solution ; Hg only,
deposited. Ag and Cd ; also satisfactory in KCy; Ag only, deposited.
Volumetric Solution of Arsenious Acid, Namias (Gazz. Chim, Ital,,
XX., 508) recommends solution of 8 grammes As^O, by heating for some
time with 300 to 400 c.c. of water containing 80 grammes NH^CjHgO,.
The solution may be used for titrating bleaching powder, chlorates, py-
rolusite, etc.
Platinum Alloys, etc, Mylius and Foerster {Zts.f,Instrumentenkunde^
^"•1 93)' ^y forming Schutzenberger's compound — distilling at 240°
in a current with CI and CO, which affords a volatile platinous chlo-
ride containing CO — very pure platinum may be obtained, or analyses
may be made of Pt alloys.
Impurities in Commercial Copper. Blount {Analyst^ xix., 92^), reports
that his method is essentially the same as Hampe's {vid. Quarterly).
The sp. gr. of Cu^CCNS)^ he finds to be 2.846 instead of 2 999 as found
by Hampe. He dissolves 13.215 grammes of the sample in aqua regia,
removes excess of HNO3 ^"^ precipitates the Cu^CCNS).^ as described
by Hampe, and then draws off 750 c.c. which (allowing tor the volume
of the Cuj(CNS)2), corresponds to 10 grammes. The distillation
method is preferred for As.
378 THE QUARTERLY.
Arsenic in Copper, Flatten (y. 5. C. /., xiii., 324), 20 grammes ig-
nited Fe^Oj are dissolved in 150 c.c. HCl and boiled in a Wurz flask con-
nected with a condenser. When (?o c.c. have distilled over the distillate
is tested with H.^S. If no As^Sj appears, the reagents are assumed to be
pure, and 10 grammes of drillings of the copper to be tested, are added
to the flask, which is then heated until all the As has been distilled over.
The distillate is saturated with H,S, filtered at once, the precipitate
washed carefully, and then boiled with 400 to 500 c.c. of water for i or
2 hours which will dissolve it, when the HjAsO, may be titrated with
centinormal iodine.
Estimating Cadmium. Muspratt (y. S, C, /., xiii., 211) has investi-
gated the methods in use.
1. Precipitation by Na,COj, igniting and weighing CdO. The pre-
cipitate often contains some basic salt. Ignition converts much of it to
CdjO, and strong ignition appears to volatilize the oxide as such. He
recommends separating the precipitate from the paper, igniting in a
current of oxygen, and dissolving off" the carbonate adhering to the
paper by HNO, evaporating and heating to CdO, separately weighing
this portion.
2. Rose's method, precipitation by H^S, and igniting in H gas, gave
good results but was too tedious.
3. Electrolytic separation in (1) KCy solution (2) dilute H,SO^ and
(3) (NH^)jC20^. These gave satisfactory results. The H^SO^ solution
is to be preferred. Dilute solutions and weak currents must be used.
Bismuth; Separation from Copper, Jannasch and I^resinsky {BericJitey
xxviii., 2908). In a nitric solution containing 0.3 gramme each of these
metals, 40 to 50 c.c. of a 3 per cent. H,0, solution with 15 c.c. cone,
ammonia effected complete separation even in the cold ; more rap-
idly if brought to boiling. Especial care is necessary in washing the
precipitate. In presence of hydroxylamine the precipitate was more
readily filtered and washed, but it was necessary to redissolve and repre-
tipitate a second time to eff*ect a perfect separation.
Sulphur in Pyrites. Gladding (y. Am, Chem. Soc, xvi., 398). HNO,
in the solution (for precipitating HaSOJgave high results, the plus error
being increased when KCl and NaC'l were present. In the absence of
HNO, those salts had no appreciable influence. The presence of Fe in
the solution always gave low results. In Lunge's method, where Fe was
first separated out by ammonia, some sulphuric acid was invariably car-
ried down with the ammonia precipitate, which could be recovered by
resolution and reprecipitation. The method recommended is essen-
tially the bromine method, already described by Ferguson (vi/fe Quar-
terly, XV., 155). A review of various methods is given in Pres. Zts,
Anal, Chem, (xxxiii., 208) by Hinz.
Phosphorus in Steel, etc, Doolittle and Eavenson {J, Am, Chem, Soc,^
xvi., 234). Experiments which are fully described indicate that the
ratio of P. to MoO, in the yellow precipitate is 1.797 : 100.
In using a reductor, the results were not concordant unless the solu-
tion poured through was hot, and the column of Zn was of considerable
length. Reduction with Zn in a flask, as prescribed by Emmerton, may
easily be incomplete.
ABSTRACTS. 379
As in the solution seemed to be without influence, except as mechani-
cally dragged down with the phosphorus.
The *• acetate" (or *' citric acid**) method (gravimetric) was found
to give low results.
Phosphorus in Irons ^ etc, — Alkalimelric Method, Handy (y. Am,
Chem, Soc, xvi., 231). An investigation as to the interference of As
with the titration indicated that the precipitation of As with the P^Oj
precipitate is a mechanical one, and may be obviated by redissolvingihe
yellow precipitate in ammonia and reprecipitating.
Phosphoric Acid, by alkalimetric titration of the molybdate precipi-
tate. Pemberton {J, Franklin Inst,^ Feb. 20, 1894). In a former paper
(Quarterly, xv., p. 156), the ratio between the P^O^ of the precipitate
and the standard alkali was recorded as 23.2 mol. Na,0 to i mol. P^O^.
Careful experiments show that the ratio should be made 23.0 instead of
23.2, or 323.7 c.c, of normal H^SO^ should be diluted to i litre, and the
alkali solution should be made to correspond c.c. for c.c. to obtain a
solution of which 1 c.c. = 0.001 gramme PjO^.
Volumetric for Phosphoric Acid,^ Holleman {Fres. Zt, Anal, Chem.^
xxxiii., 185). If a slight excess of standard AgNO, solution is added
to a neutral solution of the phosphate containing some NaCjHjOj.
AgjPO^ is precipitated, and in an aliquot part of the filtrate therefrom,
the amount of Ag in excess may be titrated by NH^CNS (Volhard's
method). The process has been found applicable to HNO, solution of
Ca, (PO^),. A large excess of AgNOj solution must be avoided.
Citrate Soluble Phosphoric Acid, Ross {J, Am, Chem. Soc, xvi.,
304). To estimate the citrate soluble phosphoric acid directly, the
author recommends after the 30 minute digestion with 100 c.c. of
15 c.c. cone. HjSO^, and heat until foaming ceases, then add HgO or
metallic Hg ; heat until colorless. Cool, dilute, neutralize with ammo-
nia, add HNOj and precipitate with molybdate mixture.
Methods for Determining Boric Acid, Hefelman {Pharm, CentrWi.,
ix., 116), and Reischle (Z/j. J. Anorg, Chem.^ iv., 1 11), have both given
recently reviews of the methods for determining BjO,. Stromeyer's
method by precipitation of 2 KFjBFj is regarded as unsatisfactory by
both.
Titration Afcthods. — In these, usually two indicators must be em-
ployed. Borates insoluble in water must "be dissolved in some mineral
acid (HClor H^jSO^). The free mineral acid must then be titrated with
an indicator which is unaff*ected by H3BO3 and in another portion the
titration is performed with an indicator which is sensitive to HjBOj.
For indicators unaff'ected by HjBOg, Congo red and Helianthin have
been recommended. For those sensitive to H^BOg, orcein and litmus. The
latter when suitably prepared (de Luyne's method), gives a wine red with
HjBOj perceptibly different Irom the ordinary red imparted by mineral
ands. Hefelman finds Parmentier's method (titration with Helianthin,
and with litmus) satisfactory. Reischle does not.
38o THE QUARTERLY.
Wills* titration with standard Ba(0H)2 was found to lack sharpness.
Rose's method — determination of the CO,, evolved by fusing a borate
with Na^COj, is condemned by both.
Hefelman reports Gooch's methyl alcohol distillation method as giv-
ing variable, and usually low results.
Determining B^Oj by loss on heating with NH^F or HF and H^SO^
was found by both to be the most satisfactory, though the details of the
manipulations used by the two experimenters differed materially. Reis-
chle*s plan was the simpler. The material is mixed (in Pt dish) with
six times its weight of NH^F, warmed slowly to drive* off the most of the
2 NH^F, BF,. cooled, and then cone. H^SO^ is added, which is heated
off, finally leaving the bases as sulphates, which are weighed. From the
difference in weight the 6,0, is calculated.
Carbonic Acid in Presence of Soluble Sulphides. Wolkowicz {Zts,
Angew. Ch.^ 1894, 165). Adding a 20 per cent. CuCI, solution will
hold back the H^S on acidifying, allowing only CO^ to escape.
Methods for Total Carbon in Iron. Gottig {Abh. d, Ver, Bef d.
Gewerbefl., viii., 321). The conclusions are :
I. Direct estimation by combustion of the iron in a current of oxy-
gen yields low results, and cannot in any case be recommended.
II. Wet combustion (H^SO^ and CrOj) can be directly applied. It is
advisable to use a good excess of CrO, (12 to 15 times that of the iron),
and to include a tube of glowing CuO and a drying apparatus before
the absorption bulbs.
III. In methods involving the solution of the iron in CuSO^ there is
no need to separate the precipitate Cu from the carbon if the wet com-
bustion is applied.
As regards graphite determinations, the author observes :
1. Thorough boiling with HNO3 or HCl renders subsequent washing
with KOH, alcohol and ether unnecessary, and gives better results.
2. As compared with HCl, the use of HNO, may lead to low results.
3. HNO3 is preferable to HCl, in that it more readily affords a residue
free from combined carbon.
Silica Estimation. Cameron (C/4^w. A^ifZ^/J, Ixix., 174). Dehydration
on a water-bath left about 3 per cent, in solution ; over a naked flame,
under 2 per cent, remained dissolved. Filtering and evaporating a
second or even a third time before all silica is separated is necessary.
Evaporating without filtering off did not seem to be effective.
Dehydration with H,SO^ proved no more effective than evaporation
with HCl. A large excess acted no better than a small excess.
In presence of Al^O, or Fe^O^, especially Al^Og, insoluble compounds
of those bases tended to remain with the SiO^ when H^SO, was used.
The presence of Ca salts seemed to have no effect in the separation.
New Element ? Bayer (C//^/f/. A^<rav, Ixix., 256). In the examina-
tion of a French bauxite some reactions were obtained which seemed to
indicate the presence of an element hitherto unknown. The amount
of material was, -however, too small to permit of satisfactory exami-
nation.
BOOK REVIEWS.
The Mineral Industry : Its Statistics, Technology and Trade in the United States
and Other Countries from the Earliest Times to the End of 1893. VoL II. Edi-
ted by Richard P. Roth well. New York : The Scientific Publishing Co. 8vo.
I'his second volume supplements and vastly increases the mass of in-
formation furnished in the first volume as to the history, occurrence,
methods of mining and preparing for market, uses, prices current, etc.,
of the many economically important minerals and mineral aggregates.
The substances discussed in Vol. I. are further considered, especially
with reference to changes and production during 1893, and chapters upon
many economically less important elements as arsenic, cadmium, bis-
muth, iodine, magnesium, phosphorus, sodium, tungsten are added.
Building materials as limestone, marble, lime and slate and such min-
eral substances as gypsum, magnesite, peat, mineral wax, marl, alum,
copperas, bauxite, etc., are considered in separate chapters, with greater
or less thoroughness. A chapter on abrasives, for instance, discusses
corundum and emery, infusorial earth and carborundum, but omits
garnet and quartz, of which thousands of tons are used as abrasives,
especially in the sand papers.
A feature of great value is the insertion in the different chapters of
articles by specialists which are not simply statistical but which present
a definitely mastered synopsis of great industries or group of industries,
and in the opmion of the writer the most permanent value of the work
is in these. '* The History of Alkali Manufacture in Great Britain," by
A. M. Gibson, is perhaps the most striking article, but is closely matched
in interest by the chapters on " Aluminum," by Prof. Joseph Richards ;
** American Practice in Electrolytic Copper Refining," by Titus Ulk6;
the very thorough articles on "Clays," by Henrich Ries, and on ** Sul-
phur," by J. F. Kemp, and the historical rfeumfes, by W. R. Ingalls, on
*' Distribution and Production of Lead," and "Present Condition of
the Zinc Industry in Europe.'*
Other special articles are :
"Sketch of Certain Advances in Iron and Steel Metallurgy in 1893,"
by H. M. Howe.
" Recent Improvements in the Treatment of Argentiferous Lead
Ores," by H. O. Hofman.
"Improvements in Metallurgy of Copper during 1893," by E. D.
Peters.
"Present Practice in Copper Concentration and Extraction," by
Titus Ulk6.
''Open-Hearth Work at Steelton," by H. H. Campbell. •
** The Future of Copper-Mining in Montana," by Albert R. Ledoux.
"Gold Resources of Colorado," by T. A. Rickard.
"The Rare Elements," by W. R. Ingalls.
"Limestone Marble and Lime," by T. C. Hopkins.
VOL. XV.— 26
383
THE QUARTERLY.
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O
BOOK REVIEWS. 383
"Treatment of Franklinite/' by Titus Ulke.
** Gold and Silver Mining in South America/* by Courtenay de Kalb.
** Cuprous Chloride Process," by C. Hoepfner.
In reading over the work the enormous aggregate value of the mineral
products of the world each year becomes more and more apparent, and
m an attempt to obtain a bird's-eye view of this the writer compiled
from the book the table on the opposite page, in which, as far as possi-
ble, the values given are those of the crude ore or mineral prior to any
metallurgical or chemical treatment. With certain metals as gold, silver
and tin, the values are chiefly those of the extracted metals.
The returns for some countries are very incomplete and the aggregate
value is much larger than that given, and it is also obvious that the
statistics for building stones, iron-ore, manganese-ore, nickel and cobalt-
ore, phosphates, precious stones and clays, are not complete. It is to
Omitting the products, arsenic, alum shale, asbestos, barite, bauxite,
bismuth, chrome-ore, corundum, cryolite, feldspar, fluorspar, iodine,
lime, magnesite, marl, mica,mineral paints, mineral water, nitrates, natural
gas, ozocerite, platinum, potash salts, soapstone, tungsten, titanium,
uranium, which are mined in only a few localities, but which, as re-
corded, aggregated in 1892, over $100,000,000 as crude material, and remembering the host of smaller less important minerals for which no satisfactory figures are obtainable, the value of the minerals produced in the world in the year 1892, was evidently in round numbers, at least two thousand miliion dollars. This, too, in general means the value at the place of production and in the raw state. Of this enormous sum eight products constitute four-fifths of all ; these are in order : Millions of Dollars. Coal, . . ' 8^6 ^llXCij .*■•.••••*.. 22/ Gold 137 Building stones (very incomplete, should be larger), . . , 109 Copper-ore, ........... 65 Iron-ore, 63 Petroleum, etc., 62 oaii, ..•.«..•....• 34 1603 The preparation of such a work with due care is an enormous task. It is evident that more time would secure more definite agreement be- tween the statistics by countries and by products; for instance. New Caledonia the greatest nickel- producer of the world does not appear in the statistics by countries. On the other hand, Russia is credited (p. 752), in 1 89 1 (the last year given for most Russian products), with 11,839 metric tons of asbestos; Canada (p. 706), with 6576 tons in 1893; Italy (p. 740), with none, although (p. 38), Mr. Donald states: "Small areas in only two countries, Italy and Canada, can be con- sidt^red as of any importance as producers of it.*' It is difficult at times to judge whether a reported product is mineral or metallurgical, and whether when ore and metal are both given (/-g-, U. S., antimony ore, 771 tons ; antimony, 318 tons) the ore from which the meial was derived is included in the reported ore-production or is additional ; no uniform usage seems to prevail. In the opinion of the * 384 THE QUARTERLY. writer, the quantity of ore or mineral, and its value at the place of pro- duction should be always given when obtainable, and the manufac- tured products separately except perhaps in the case of gold and silver. In endeavoring, for instance, to compare statistics of iron-ore, it was found that for the United States only pig-iron was recorded, whereas, for Great Britain the ore was recorded and the pig-iron not ; in Sweden both, and so on. These, however, are faults which can be remedied, and the great value of the work is not to be questioned. A. J. M. Le Cuivre. By Paul Weiss, Ingineur au Corps 'des Mines. Paris. J. B. Baillidre et Fils, 1894. i2mo., cloth binding, 344 pp., 96 illustrations. Typography and paper of good quality. This work is divided into three parts. The first treating of the origin, occurrence, etc., of copper. The second embraces the metallurgical treatment and the third its manufacture into commercial forms. Under part I. are di.scussed the physical and chemical properties of the metal with the various methods of analysis, and special mention is de- served of the microphotographic plates of etched polished surfaces. Il- lustrations are given of the following metals : Perfectly refined copper, imperfectly refined copper, copper with 8 per cent, phosphorus, ordi- nary bronze, phosphor-bronze, aluminium- bronze, manganese-bronzes, antifriction metals, brass, etc. These microphotographic illustrations are of good quality and distinctly show the changes in structure of the metal. Under part II. the metallurgy of copper is treated in a general way. The subject is discussed under heap, stall and furnace roasting of ore. Fusion for bronze mattes in shaft, reverberatory or oil-fired furnaces. Fusion for black copper in shaft, small or large reverberatory furnaces with a special chapter on the Swedish regenerative gas-fired furnace and Bessemerization of copper mattes. Refining of black copper in low hearth, reverberatory and electrolytic ; a special chapter is devoted to the various wet methods of extracting copper from its ores. Part III., gives the manufacture of the refined copper into the various forms as plate, wire, rods, tubing, etc., and includes a short description of brass founding. For an elementary work embracing the general metallurgical practice of copper smelting this work is commendable, but it is to be regretted that the author in briefly describing modern practice has not given the references when the details could be easily obtained by those who wished to go into the subject further than this work has advanced. J. S. Gas- Lighting and Gas- Fitting. By Wm. Paul Gerhard, C.E. Second edition. i6mo Pp. 190. Van Nostrand's Science Series. 1894. This little volume is intended for all who are in any way interested in the distribution or use of illuminating gas. Among the more impor- tant topics discussed are the piping of buildings, gas-burners and fix- tures, hints to consumers on the use of gas, and the use of gas for heat- ing and cooking. VVe notice some errors of minor importance, but on the whole the volume will be found reliable and useful. The great want at present, however, is not so much bojks like that of Mr. Gerhard's, as it is for architects, gas-fitters and consumers who will read and profit by those already written. E. G. L. ERRATA. 385 ERRATA. Wells-Cushman Schemes for Qualitative Analysis, (School op Minks Quarterly, April, 1894.) Table II.— 1st column 13th line, read (NH^)^ for (NH)^ Scheme II.— Filtrate C, 3d line, read Scheme V. for Table VII. Scheme II.— Ppt. A, 2d line, read HCl for HlC. Table III.— ist column 6th line, read HNOj for NHOg. Table VI.— ist column 7th line, read CoCl, for COClj. Table VII.— Foot-note, read BaCOj for BaCo,. Table VII.— 3d column 5th line, read KjAl^O^ for KjAl^O. Table VII.— 4th column loth line, read 2NH^C1 for zNH^Cl. Table VII.— (Concluded) ist column 8th line, read NH^Cl for NHCl. Table VIII.— Under Metals in title, 2d line, read (C^HjO,), for (CjAjOa),. Table VIII.— Under Metals in title, 3d line, read HCjHjOj for H^HgOj,. Table X.— 8th column loth line, read (CO,), for (CO3). Table XI. — 6th column 7th line, read Fe5(FeCy,)j, for Fe3(KeCyg)3. Table XIII. — 3d column 3d line, read Hg/ for H^^g. LISTS • OF THE 1894 Members op the Alumni Association and Other Graduates Detecting Errors in the Succeeding Lists Will Please Send Corrections to PKOF. F. R. HUTTON, secretary, COLUMBIA COLLEGE SCHOOL OF MINES, OR TO No. 12 West Thirty-first Street, New York City. OFFIC ERS CON8T1TUTINQ THE Board of Managers OF THE ALUMNI ASSOCIATION OF THE SCHOOL OF MINES 1894. Pre$idejU,
WILLIAM BARCLAY PARSONS, '82.
22 William St., N. Y.
Vice-Presidentf
ELWYN WALLER, 70,
33 West I5th St., N. Y.
Secratary,
F. R. HUTTON, 76.
Columbia College, N. Y.
Trectsurerj
ALFRED J. MOSES, '82.
Columbia College, N. Y.
MANAGERS.
Terms expire 18(J3. Group. Terms expire 1894.
A. W. HALE, '67. L WM. ALLEN SMITH, '68.
ARTHUR H. ELLIOTT, '8L IL E. G. LOVE, 76.
R. W. HILDRETH, '85. III. EDWIN P. CLARK, '80.
GEO. R. TUSKA, '91. IV. D. LeR. DRESSER, '89.
Note. — Correspondence concerning dues and other clerical details of the work o/
the Association may be conveniently addressed to Mr« Francis W.
HoADLET, Assistant to the Secretary and Treasurer,
No. 12 West 3l8t St., New York City.
CONTENTS.
Officers of the Association, .....
List of all Graduates by Classes,
List of Members of Alumni Association (alphabetical),
List of Honorary Members, ....
List of Graduates Not Members af Alumni Association,
List of Members Classified by States and Towns, .
Cortstitution of Alumni Association,
PAOB
3
6
16
70
72
84
89
SUMMARY.
Members of Alumni Association,
Honorary Members, .
Life Members,
Associates,
800
524
6
23
13
276
(Revised to April Ist, 1894.)
LIST No. 1.
Contains the names of all Graduates and Members of
«
the Alumni Association grouped by classes from
the beginning. The details as to Residence and
Professional Occupation are given in the sec-
ond or alphabetical list for convenient reference.
(Revised to April 1st, 1894.)
— 6 —
OILij^SS LIST
OF
OF THE
ASSOCIATION OF THE ALUMNI.
[Note, — Where the name is followed by a date, it denotes that the person is no
longer living, and the date is the year of the death.]
Bridgbam, S. W.
Bronson, R S.
Brown, F. G.
Church, J. A.
Barnard, A. P*
Baxter, G. S.
Carson, J. P.
Chester, A H,
Coursen, G. 11.
Geer, G» J., Jr.
Hanna, G. B.
MacMartin, A, 1881.
Blossom, T. M., 187G.
Bnickman, F.
Campbell, A. C.
Delafield, A. F.
Hooker, W. A.
Haight, O., J 80 1.
Iiigersoll, W. H.
Knapp, J. A.
1867.
Cornwall, H. B.
Giddings, E. E.
Gracie, C. K., 1891.
Hale, A. W.
Harding, G. E.
1868.
Melliss, D. E.
MofFatt, E. S., 1893.
Parsons, G. H.
Pennington, J. P.
Pistor, W.
Piatt, c. s:
Robertson, K.
1869.
Huntington, C.
Irving, R. D., 1888.
Jenney, W. P.
Munroe, H. S.
1870.
Lilienthal, J. L.
Lindsley, S.
Parrot, E. M.
Harmer, T. H.
Heath, E. M,
Tuttle, W. W.
Van Lennep, D.
Shack, A P.
Schermerhorn, F. A.
Smith, L.
Smith, W. A.
Stalknecht, F.
Van Arsdale, W. H.
Wheeler, M. D., 1889.
Nettre, L. R.
Newton, H., 1877.
Potter, W. B-
Randolph, J. C. F.
Terhune, R. H.
Van Wagenon, T. F.
Waller, E.
— 7 —
Fales, W. E. S.
Goldscbmidt, S. A.
Gordon, J.
Austen, P. T.
Jenney, R, 1876.
Canfield, F. A.
Colton, G. A.
1871.
Ricketts, P. de P.
Riggs, G. W.
Roberts, G. S.
1872.
McDowell, R H.
Sloane, T. 0'C\
1873.
Mott, H. A.
Webb, H. W.
1874.
Allen, C. S. Lillie, S. M.
Benedict, W. de L. Murray, G.
Cameron, J. G. M., 1892. Olcott, E. E.
Ledoux, A. R. Rees, B. R
Iblseng, M. C.
lies, M. W.
Jackson, C. E.
Joy, D. A., 1888.
Lamson, R., 1876.
Leavens, H. W.
Macy, A., 1891.
Austin, T. S.
Bruen, R E., 1884.
Cornwall, G. R.
Craven, R C, 1890.
Foote, H. C.,1888.
Grarrison, E. H.
Gratacap, L. P.
Hall, R. W.
Hamilton, S., Jr.
1875.
Noyes, W. S.
Pfister, P. C.
Putnam, B. T.. 1886.
Rees, J. K.
Rolker, C. M.
Russell, S. H., 1892.
Stewart, H.
1876.
Holbrook, F. N.
Hoyt, W. L.
Hunt, R F.
Hutton, F. R.
King, C.
Lord, N. W.
Love, E. G.
Maghee, J. H.
Morewood, H. R
Robertson, R S., Jr.
Wendt, A. R, 1893.
Williams, J. T.
Rbodes, R B. F.
Williams, F. H.
Thompson, M. S.
Tucker, J. H.
Vanderpoel, F.
Wells, J. S. C.
Wetmore, E. A.
Wright, A. A.
Randolph, J. F.
Ross, W. C.
Schneider, A. F.
Tilden, G. C.
Van Blarcom, E. C.
Walbridge, A C, 1892.
Wardlaw, J. R.
Barros, L, de S.
Barus, C.
Beard, J. T.
Behr, E,
1877.
Buckley, C. R.
Canfield, A. C.
Cauldwell, J. B.
Clark, H. G., 1881,
Colby, C. E.
Constant, C. L.
Cornell, G. B.
— 8 —
Floyd, F. W.
HcUeberg, F. S., 1883.
Hildreth, W. E.
Ihlseng, A. O.
Jordao, J. N. P.
Kelly, W.
Martin, E. W.
Murphy, J. G.
Nichola, R.
Noiris, D. H.
Priest, J. K, 1880.
Mackintosh, J. B., 1891. Reed, S. A.
Rogers, C. L.
Sage, E. E.
Smeaton, W. H.
Smythe, R. M.
Thacher, A.
Van Boskerck, R. W.
Waterbury, C. R.
Benjamin, M.
Blydenburgh, C. E.
Downing, O. P.
Drummond, I. W.
Eliot, W. G.
Fernekes, A., 1884.
Haas, H. L.
Hasegewa, Y.
Hodges, H. A., 1883.
Holden, E. H.
Hollis, W.
Johnson, E. M.
Johnson, G. H.
1878.
Karr, C. P.
Booracm, R. E.
Brinkerhoff, G. C.
Butler, W. P.
Lawrence, B. B.
Lyman, F.
Martin, N.
McCulloh, E. A.
Morewood, G. B.
Morris, G. W.
Munsell, C. E.
Murphy, H. N.
Nambu, K.
Newberry, S. B.
Cushmau, A. R.
Davis, J. W.
Devereux, W. B.
Noyes, J. A.
Owen, F. N.
Palmer, C. E.
Parker, R. A.
Pazos, V. F.
Perry, N. W.
Strieby, W.
Willis, B.
Bolton, R.
Britton, N. L.
Cloud, L. G.
Cornwall, H. C.
Dcluze, L. P.
Eastwick, G. S.
Haffen, L. F.
Harker, C. 8.
Hathaway, N.
Hollerith, H.
Hollick, C. A.
Johnson, I. B.
1879.
Johnston, R. A.
Koch, E. C.
Leggett, T. H.
Ludlow, E.
Marsh, C. W.
Mathis, T. S.
Mayer, R. E.
Merwin, H. J.
MiUiken, G. F.
Munroe, O. M.
Neftd, K.
Nesmith, J.
Noble, C. M.
Reed, W. B. S.
Rhodes, R. D.
Rutherford, F. M.
Sheldon, G. H., 1889.
Starr, H. F.
Stewart, F. B., 1879.
Stone, G. C.
Suydara, J. R, Jr.
Williams, G. W.
Beebe, A. L.
Benjamin, F. P., 1893.
Browning, F. D,, 1885.
Browning, J. H. B.
Brugman, W. F.
Buller, N.
1880.
Churchill, A. D.
Clark, E. P.
Elliott, W.
Engel, L. G.
Francke, R. 0.
Garlichs, H.
Greene, W. U.
Grcenleaf, J. L.
Hallock, A. P.
Hendricks, H. H.
Hooper, L. M.
Hopke, T. M.
I
— 9 —
Hudson, E. E.
Klepetko, F.
Kunhardt, W. B.
Mattison, J. G.
Meissner, C. A.
Merritt, J. H.
Navarro, J. A.
Parker, A. McC.
Parks, J. R.
Robinson, H. A.
Ruttman, F.
Singer, G.
Singer, G. H.
Smalley, W. B., 1886.
Smith, M.
Tonnel€J, T.
Torrey, C. H.
Walker, J., Jr.
Wheeler, II. A.
Andresen, C. A.
Aschman, F. T.
Bleecker, C. P.
Braschi, V. M.
Bush, E. R.
Chazal, P. E.
Colby, A. L.
Curtis, C. G.
Douglas, E. M.
Dunham, E. K.
Elliott, A. H.
Furman, H. V. P.
Griswold, W. T.
1881.
Hemmer, F. A.
Judd, C. B.
Leary, D. J.
LeBoutillier, C.
Jjedoux, A. D.
Little, W. P.
Meserole, W. M.
Neyniann, P.
O'Connor, M. J.
O'Connor, T. D.
Pitkin, L.
Raymer, G. S.
Richmond, W. T.
Roberts, A. C.
Sawver, C. P.
Share, W. W.
Starr, C. D.
Stearns, T. B.
Swain, A. E.
Tuttle, E. G.
Van Sinderen, A. H.
Vult6, H. T.
Wiechmann, F. G.
Williams, W. F.
Wilson, H. M.
Caiman, A.
Conant, T. P., 1891.
Cooper, W. H.
Crocker, F. B.
Dougherty, O. V., 1889.
Downes, S. B.
Downs, W. F.
Emrich, A. F., 1893.
Falk, D. B.
Feuchtwanger, H.
Fitch, C. L.
Going, C. B.
Hill, W.
1882.
Illig, W. C, 1894.
Joiiet, C. H.
Mesa, A. E.
Moses, A. J.
Oothout, E. A., 1894.
Page, W. S.
Parsons, W. B.
Payne, C. Q.
Porter, J. B.
Powers, C. V. V.
Sands, F.
Shumway, W. A., 1892.
Staunton, W. F.
Stockwell, N. S., 1888.
Toucey, D. B.
Traphagen, F. W.
Vondy, R. H.
Wain Wright, J. H.
Wanier, A. G.
Ward, N. R.
White, W. S.
Wilson, W. A.
Wittmack, C. A.
Young, E. L.
Abeel, G. H.
Ayestas, A.
Balch, S. W.
Banks, J. H.
Bardwell, A. F.
1883.
Biereton, T. J.
Brewster, H. D.
Bullman, C.
Carr^re, J. M.
Channing, J. P.
Endicott, G., 1889.
Ferrer, C. F.
Ferris, J. C.
Fiallos, E. C.
Haasis, D. F.
Humbert, W. S.
Lilliendahl, A. W.
— 10 —
MacTeague, J. J.
McKenna, C. F.
Oxnard, J. G.
Painter, J. G.
Paraga, C.F.
Peele, R, Jr.
Alden, H. C.
Baldwin, W. M.
Barnard, E. C.
Barratt, E. G.
Bodelsen, 0.
Brinley, J. R.
Bryce, W.
Buckingham, F. E.
Burritt, W. W.
Corcoran, J. T.
Del Calvo, F.
Duncan, W. P., 1889.
Duseu berry, W. T.
Easton, L. C.
Fahys, G. E.
Fitch, J. H.
Fitzgerald, G. E.
Fowler, S. S.
Glover, C. G., 1888.
Gosling, E. B.
Amy, E. J. H.
Barkley, H. F.
Bemis, F. P.
Brennan, A. J.
Bush, W. F.
Gary, G.
Clark, F. S.
Cozzens, H.
Crowell, C. B.
Detwiller, C. H.
Doolittle, C. H.
Dwight, A. S.
Eddie, E. C.
Engelhard t, E. N.
Graflf, C. E.
Hart, B.
Powell, F.
Randolph, E.
Renault, G.
Rich, J. M.
Richardson, J. C.
Ridsdale, T. W.
1884.
Griffin, S. P.
Gross, L. N.
Horn, J. T.
Kemp, J. F.
Lamb, A. J.
Luttgen, E.
McGenniss, J.W.Jr., 1890
McKim, R. A.
McLoughlin, C. S.
Miller, C. W.
Moeller, W., 1887.
Moran, D. E.
Morgan, W. F.
Mulford, R.
Napier, A. H.
Newberry, W. E.
Newbrough, W.
Nolan, F.
Northrop, J. I., 1891.
Nye, A. C.
Painter, C. A-
1886.
Hawkes, E. McD,
Hildreth, R. W.
Hollis, H. L.
Huntington, F. W.
Ingram, E. L.
Johnson, A. G.
Lacombe, C. F.
Jjce, G. B.
Mannheim, P. A. L.
Mari6, L.
Meyer, H. H. B.
Merrill, F. J. H.
Miller, C. L.
Moldehnke, R. G. G.
Noble, L. S.
Norris, R. V. A.
Suter, G. A.
Tibbals, G. A.
Tower, A. E.
Walker, A. L.
Weed, W. H.
Pearis, C. F.
Pellew, C. E.
Post, A. S.
Powers, L. J.
Proctor, W. R.
Reckhardt, D. W.
.Roeser, F.
Rood, R. G.
Rowland, C. B.
Rupp, P., Jr.
Schoney, E., 1888.
Sherman, F. D.
Slack, C. G.
Smedberg, H. A.
Snook, T. E.
Speyers, C. L.
Tibbals, S. G.
Value, B. R,
Walbridge, F. K.
Wood, G. E.
Page, G. S.
Pierce, H. N.
PoUedo, Y. Y.
Sanders, W. E.
Shope, H. B.
Starek, E.
Struthera, J.
Thomas, F. M.
Titus, W. H.
Van Cortlandt, E. N.
Watson, F. M.
Whitman, E. P.
Wiltsie, E. A.
Woolson, I. H.
— 11 —
I .
Agramonte, E., Jr.
Agramont^, J. C.
Bell, H. M.,Jr.
Berry, W. G.
Casey, E. P.
Conant, H. 1).
Edwards, R M.
Frankfield, E.
Good, G. McC. H.
Home, W. D.
Howe, E).
Aldridge, W. H.
Appleby, W. R.
Bellinger, H. P.
Bien, J. R.
Bums, A. L.
Burns, E. Z.
Butler, W. C.
Church, E. D.
Cole, H. M.
Congdon, E. A.
Cox, J. S., Jr.
Darwin, H. G.
Davis, C. H.
Donnell, H. E.
Ferguson, W. C. A.
Gage, S. E.
Goldsmith, B. B.
Gudeman, E.
Allen, R. L.
Appleby, J. S.
Baker, G. L.
Bartlett, F. R.
Beohstein, C. A.
Beck with, C. E,
Berry, G.
Colt, S. B.
Comstock, C. N.
Dodge, F. D.
Dodsworth, W. A.
Dow, A. W.
Fisher, W.
Frank, J. W.
1886.
Janeway, J. H.
Jenks, A. W.
Kissam, H. S.
Lederle, E. J.
Lee, H. C.
Newhouse, E. L.
Norton, L. H.
Ormsbee, J. J.
Osterheld, T. W.
Peck, S. B.
Porter, H. H., Jr.
1887.
Heinsheimer, A. M.
Huntting, H. O.
Jacobs, D. M.
Jacobs, S. J.
Jeup, B. J. T.
Lahey, J.
Lahey, R.
Luquer, L. McI.
Lusk, G.
MacKaye, H. S.
Mannheim, H. C.
Marsh, J. R.
Middle ton, J.
Moeller, R.
Muller, G.
Nichols, H. P.
Primelles, J. A.
Restrepo, C.
1888.
Gardner, W. D.
Hebert, O. B.
Hopkc, F. E. , 1 890.
Jones, W. D.
Koen, J. J.
Lenox, L. R.
Lipps, H., Jr.
Mcllvaine, A. R.
Maclay, J.
Morgan, L.
Miller, R. P.
Munoz del Monte, A.
Parker, 0. B., 1891.
Parsons, H.
Ryon, A. M.
Spooner, A. N.
•Stodder, R H., 1887.
Stuart, W. H.
Thompson, H. C
Trowbridge, S. B. P.
Van Brunt. A. H.
Von Nardroff, E. R
Wallace, W. J.
Wheatley, J. Y.
Wilson, C. E.
Rice, G. S.
Rowland, G.
Rutherford, L. H.
Schieffelin, W. J.
Seligman, J. G.
Siraonds, F. M.
Stanton, F. McM.
Staunton, J. A., Jr.
Stevens, A.
Tower, F. W.
Tyler, W. L.
Warner, J. L.
Wels, P. 0.
Wertheimer, L.
Percival, G. S., 1892.
Perkins, T. S.
Schumann, C. H.
Shriver, H, T.
Smith, F. P.
Smyth, C. H., Jr.
S tough ton, A. A.
Taylor, J. B.
Tucker, A.
Van Dyck, E.
Van Volkenburgh, E.
C. Volckening, G. J.
Wampold, L.
Ward, D. W.
— 12 —
Atha, H. G.
Berry, G.
Brown, R. G.
Cramer, S. W.
Cromwell, J. W.
Denton, F. W.
Dresser, D. LeR,
Eastwick, E. P.
Eilers, K. E.
Ellis, A. V. H.
Escobar, F.
Fearn, P. LeR,
Fowler, A. C.
Freedman, W. H.
Gifford, S. D.
Griffith, V. C.
Griggs, W. E.
Guiterman, E. W.
Andrews, S. W.
Beck with, G. A.
Behlen, H.
Betts, R. T.
Black, A. L.
Blake, E. M.
Book, D. D.
Buckland, W. A.
Cairns, F. I.
Carson, J.
Clark, D. L.
Clayton, W. R.
Colton, F. G.
Connell, fl. R.
Coykendall, T. C.
Davis, W. M.
Deghnee, J. A.
Anderdon, Geo.
Bliss, C. P.
Blossom, F.
Boecklin, W.
Boyd, R. C.
1889.
Harrington, T. H.
Harris, E.
Heinze, F. A.
Holt, M. B.
Ives, A. S.
Jopling, R. F.
Luquer, T. T. P.
Mahony, A. S.
Mapes, C. H.
Mason, C. S., 1889.
Massa, C. G.
Matthews, C. T.
Monell, J. T.
Mosley, R. K.
Oseransky, I. H.
Piez, C.
Post, A. Van Z.
1890.
Douglas, J. S.
Ferguson, G. A.
Fisher, L. W.
Foy^, A. E.
Gudewill, C. E.
Gould, E. C.
Hart, C. H.
Hewlett, J. M.
Hicks, G. J., 1891.
Hinman, B. C.
Hooper, F. C.
Hoyt, J. S.
Hurlburt, E. D., Jr.
Jarmulowsky, M.
* Jones, T. J.
Kohn, R. D.
Korn, L.
Levy, A. L.
1891.
Brosnan, F. X.
Cristy, E. B.
Eberhardt, Wm. G.
Goodwin, E.
Hawley, J. F.
Preston, W. E.
Provost, A. J., Jr.
Provot, G.
Raymond, R. M.
Raynor, R.
Rogers, 0. L.
Schroeder, J. L.
Skidmore, S. T.
Small, F. M.
Smith, A.
Smith, F. M.
Stoughton, C. W.
Waters, G. S.
Wedekind, E. H.
Weekes, E. F., 1893.
Weeks, W. H.
Whitlock, H. P.
Lichtenstein, E. G.
Lowndes, W. S.
McKleroy, W. H.
Mann, H. B.
Massa, L. F.
Meikleham, T. M. R,
Montenegro, M. R.
Parker, H. C.
Portuondo, J.
Post, W. S.
St. John, T. M.
Steers, J. R.
Thome, W. L.
Wainright, R. T.
Warren, C P.
Welch, A. McM.
Welsh, H. F.
Holter, N. B.
Hornbostel, H. F.
Keeler, F. S.
Kinsey, F. W.
Langthorn , J. S.
— 13 —
Leary, Geo.
Lilliendahl, F. A.
Livingston, A. E.
Mahl, J. T.
Miller, E. H.
Mora, M. K
Ansbacher, L. A.
Anthon, A.
Bergen, C. H.
Bolles, R.
Burden, H., 2d.
Casamajor, G. H.
Clark, Edmund.
Clarke, W. C.
Dolan, C. F.
Dufourcq, E. K
Durham, E. B.
Dutoher, B. H.
Fenner, C. N.
Friedman, S.
Agramonte, I. E.
Aldrich, C. H.
Ayres, W. C.
Bebrman, G. W.
Bossange, E. R.
Brooks, W. F.
Canfield, M. C.
Clark, G. H.
Covell, W. S.
Foster, R. G.
Gregory, L. E.
Hankinson, A. W.
Harte, C. R.
Raymond, A.
Skinner, E.
Strout, W. A.
Thomas, F. C.
Totten, G. 0., Jr.
1892.
Gillette, H. P.
Granger, A. D.
Hay, A.
Herckenrath, W. A.
Jackson, 0.
Kletchka, J. J.
Livingston, G.
Longacre, L. B.
Jiord, F. R.
McTlhiney, P. C.
McKinlay, J. B.
Meisel, F. C. A.
Merz, E.
1893.
Hoyt, R.
Hyde, F. S.
Jones, J. E.
Kurtz, E. L.
Langmuir, A. C.
Liebmann, A.
McKee, S. H.
Macy, V. E.
Malukoff, A. J.
Matthew, W. D.
Newton, T. M.
Oakes, J. C.
Tucker, S. A.
Tuska, G. R.
Warren, L.
Watson, R. B.
Wiener, Wm.
Pierce, F. K.
Reckhart, G. F.
Ries, H.
Rosenthal, A.
Savage, S. M.
Southard, G. C.
Temple, S. J.
Towart, J.
Vanlngen, D. A.
Werner, H. C.
White, R. D.
Windecker, C. N.
Windolph, A. P.
Pederson, F. M.
Pomeroy, W. A.
Post, R. B.
Prince, A. D.
Provot, F. A.
Reynolds, M, T.
Robinson, F. G.
Schrotef, G. A.
Smith, H. A.
Thompson, S. C.
Tilghman, H. A.
Tuttle, W.
LIST No. 2.
This list embraces the members of the Alumni
Association of the School of Mines under the
Constitution of that body. It is urged that all
graduates of the School should list themselves
grouped in List No. 3, Tvhich includes graduates
who are not also members. All graduates are
requested to try to make and keep this list correct
and accurate.
— 16 —
:h/LJSii^'B:EiTts
OF THE
ALUMNI ASSOCIATION OF THE SCHOOL OF MINES.
Abeel, George Howard, E.M , 1883.
Box 638, Hurley, Iron Co. , Wis.
1883-1884, Chemist Iron Cliffs Co., Ne^aunee, Mich. 1885-1688, Assistant Manager
Cliflfe Co., Negaunee, Mieh, 188(>-1887, Supt. Negaunee Gas Light Co., Mich. 188&-
1889, Manager Ironton Iron Mining Co., Bessemer, Mich. 1888-1889, Agent Pilgrim
Mining Co., Bessemer, Mich. 1889, Supervisor Bessemer Township, Gogebic Co.,
Mich. 1889-1892, Agent Ruby Iron Mining Co., Bessemer, Mich. 1888 to date,
General Manager of Montreal River Iron Mining Co., Hurley, Wis. 1892 to date,
Vice-President First National Bank, Hurley. Wis. 1892 to date, Vice-President Wis-
consin Mining Supply Co., Hurley, Wis. 1893, Vice-President and General Manager
Section 33 Iron Mining Co., Hurley, Wis.
Broken Hill, N. S. Wales, Australia.
1884-87, Assistant Superintendent and Superintendent of the Silver King Mine,
Silver King, Arizona. 1887-91, engaged in Australia as Mining Superintendent and
Mining Expert, and now Manager of the Central Broken Hill Mine, Broken Hill,
N. S. Wales, Australia.
Adams, William Crittenden, C.E., .... 1884.
47 W. 28th St. and 200 West End Ave., N. Y. City.
Agramonte, Emilio, C.E., . , 1886.
118 E. Seventeenth Street, New York City.
Aldridge, W^ alter Hull, E.M., 1887.
Manager United Smelting and Refining Co., East Helena, Montana.
Beginning July, 1887, Assayer at Colorado Smelting Co., Pueblo. At different
times. Chemist of Colorado Smelting Co., Pueblo. August, 1890-91, Assistant Su-
perintendent and Metallurgist of Colorado Smelting Co., Pueblo. Assistant Manager
United Smelting and Refining Co. 1893, Manager as above.
Allen, Chas. Sumner, Ph.B., M.D., .... 1874.
Practicing Physician.
— 17 —
Allen, Egbert Lawrence, A.M., E.M., . . 1888.
102 Cambridge Place, Brooklyn, N. Y.
Amy, Ernest Julius U yacinthe, A.B., E.M., . . 1885.
Durango, Colo.
1885-1886, Chemist and Assayer at works of the San Junn and N. Y. M. and S. Co.,
at Durango, Colo., with the exception of three months' professional visit to Old
Mexico. 188G-1887, Assistant Manager of the San Juan and N. Y. M. and S. Co., at
Dnraugo, Colo. 1887-1888, Manager of the Hazelton Mountain Mining Co., at Sil-
verton, Colo. 1888 to April 1, 1890, Assistant Manager of Works of the San Juan
Smelting and Mining Ch)., at Durango, Colo, (the S. J. S. and M. Co. being formed by
the consolidation of the S. J. and N. Y. M. and S. Co., of Durango and the Hazelton
Mt. Mfg. Co., of Silverton, CoIo.)i Since April 1, 1890, General Manager of the San
Juan Smelting and Mining Co.. at Durango, Colo.
Andrews, Samuel Wakeman, Jr., Ph.B., . . . 1890.
Andrews, Waters & Sherwin, 35 W. Forty- second Street, New York
City.
1890-1891, Designing with Tiffany Glass and Decorating Co., New York. 1891 to
date, member of above firm.
Ansbacher, Louis Adolph, Ph.B., .... 1892
A. B. Ansbacher & Co., 4 Murray St , New York Cit\\
Anthox, Archibald (Associate), 1892
458 Pleasant St., Maiden, Mass.
Appleby, W. R., A.B. (Associate), 1887
Professor of Mining aud Metallurgy, University of Minnesota, and 911
Fifth St., S. E., Minneapolis, Minn. ; also 29 Bentley Avenue, Jer
sey City, N. J.
Atha, Henry Gurney, Ph.B., 1889
756 High Street, Newark, N. J.
AusiEN, Peter Townsend, Ph.B., Ph.D., . 1872
Polytechnic Institute and 876 President St., Brooklyn, N. Y.
1878-1880, Assistant Professor of Analytical Chemistry, Rut;:rers College. 1880-
1889, Professor of General and Applied Chemistry, Rutgers College. 1891, Superin
tendeut Manufactories of W. J. Mutheson & Co., limited, Ravenswood, N. Y. 1892
General Manager, Ledonx Chemical Laboratory. 1893, Professor of Chemistry, Poly-
technic Institute, Brooklyn, N. Y.
Austin, Thomas Septimus, E.M., 1876.
Albuquerque, New Mexico.
1877-1878, in Cuba as Chemist. 1879-1880, Assayer German la Smelting Co. 1880-
1890, Superintendent Rio Grande Smelting Co., Socorro. N. M.
B.
Baker, George Lewis, Ph.B., 1888.
Balch, Samuel Wekd, E.M., 1883.
Box 333, Yonkers, N. Y., and 757 Equitable Building, N. Y. City.
1883-1884, Otis Elevator Co. 18K4-iaH(), Mowing Machines. 1880-1889, Garvin
Machine Co., Tools and Special Machinery. 18vS9 to date, General consulting practice
aa Mechanical Expert and Patent Attorney. Specialty, Difficult Mechanical Problems.
2
— 18 —
Baldwin, William M., Ph.B. (Life MemW), . . 1884.
55 Beekman St., N. Y. City, and Garden City, Queens Co., N. Y.
Since 1885, Chemist for the New York Dye Wood Extract and Chemical Co. Since
1888, Vice-President of the above corporation, and at present having charge of their
man ufac taring department.
Banks, John Henry, E.M., 1883.
104 John Street, New York City.
1883-1885, Chemist with Ledoux & Ricketts, New York. 1885-1891, Private As-
sistant to Prof. Ricketts, School of Mines, New York, in general analytical, metallar-
gical and mining engineering work. 1889-1891, Hon. Fellow in Assaying, School of
Mines. 1891 to date, in partnership with Prof. Ricketts, at above address, in general
chemical, metallurgical and mining engineering work, with Ore-Testing Works, at
Waverly.'New Jersey, for determining treatment of ores, and examination of pro-
cesses.
Bardwell, Alonzo Frick, E.M, 1883.
Box 773, Aspen, Col.
Barnard, Edward Chester, E.M., .... 1884.
U. S. Geological Survey. Washington, D. C.
Assistant Topographer and at present Topographer in the United States Geological
Survey, 1884-1891. Have been engaged in mapping in Virginia, West Virginia,and
the mountains of East Kentucky. 1893. Mapping Northern New York.
Barratp, Edgar Grant, C.E., 1884.
1022 The Rookery, Cliicago, III.
1884-iaS8, Engineer for The Exiiaust Ventilator Co. 1888 to date, President and
Proprietor of The Exhaust Ventilator Co. 1891 to date. President and General Man-
ager of the Variety Maimfacturing Co. Fill the above positions at present and am
consulting Ventilating and Heating Engineer.
Bartlbtt, Ficank Root, C.E., 188S.
Care R. & D. R.R., P. O. Box 14, Greensboro, N. C.
1888 to date. Assistant Engineer Maintenance of Way on Atlanta and Ch^lotte
Division of Richmond and Danville Railroad. From May, 1892, to date, Supervisor of
North-western North Carolina and North Carolina Midlands R. Roads ( North Carolina
Division of Richmond and Danville Rail Roads).
Barus, Carl, Ph.D. (Associate), 1877.
National Museum, Washington, D. C.
Baxter, George Strong, A. B., E.M., .... 1868.
17 Broad Street, New York City.
1878-1879, Civil and Mining Eiiginoer. 1880, Cashier N. P. R.R, 1890, Treasurer
N. P. R.R.
Beard, Jamf^ Thom, E.M., C.E., 1877.
1879-80, Assistjint Engineer, East River Bridge.
Beebe, Alfred L., Ph.B., 1880.
42 Bleecker Street, New York City and 44 Sanfrid Av., Fiusliing, L. I.
1880-1887, inclusive. Private Assistant to Prof. Ricketts, School of Mines, New
York, in general analytical work, especially Mineral Analyses. Also Assistant in
Assaying and Fellow in Clicmistry, 1881-1887, inclusive. 1888-1892, Assistant
Chemist, New York Health Deimrtment. Since September, 1892, Bacteriologist,
New York Health Department.
— 19 —
Behrman, George William, C.E., . • . . 1893.
201 Ross Street, Brooklyn, N, Y.
November, 1893, to January, 1894, Transitman and Draughtsmau, with the Ranb
Locomotive Works and Land Improvement Company.
Bellinger, Hiram Paulding, C.E., .... 1887.
Solvay Process Company, Syracuse, N. Y.
Bemis, Frederick Pomeroy, A.B., E.M., . . . 1885.
109 West 3d St., Davenport Iowa.
Benedict, William de Liesseline, E.M., . . 1874.
Welles BId'g, No. 18 Broadway, Rooms 617 and 618, New York City,
and 282 Vandcrbilt Avenue, Brooklyn, N. Y.
1878-1880, Assistant Superintendent and Superintendent, Revere Concentrating
Co., Utah. 1880-1681, Assistant Superintendent, Germania Smelting & Refining Co.,
Utah. In 1882, opened an office in New York City as C^onsulting Mining Engineer
and Metallurgist, and have since been engaged in examining and reporting on Mines
in the United States, Ontario, Quebec, British Columbia, Mexico and England.
Benjamin, Marcus, Ph.B., A.M. (Lafayette 1888) (LifeMbr.) 1878.
Ph.D. (Univ. Nashville, 1889), Editor, D. Appleton& Co., No. 1 Bond
Street and 640 Madison Avenue, New York City.
1878-1882, with E. B. Benjamin, dealer in Chemical Apparatus. 1882, Editor Ameri-
can Pharmacist. 1883, Editor Weekly Drug iVetr«, May, 188,'i, to June, 1885, Chemist, U. S.
Laboratory, New York. 1885, Sanitary Engineer, N. Y. Board of Health. 1886-89,
Editorial Staif, Appleton's Cycloptedia of American Biography. 1890, Editorial Staff, En-
gineering and Mining Journal^ chiefly engaged in editing and preparing for the press,
George F. Kunz's Gema and Precious Stones of North America. 1891-93, Editor of Gen-
eral Guide to the United States, Handbook of Winter Resorts, and Handbook of Summer Re-
sorts^ publislied by D. Applotou & Co. Editorial Staff in charge of Chemistry,
Standard Dictionary, 1891-93. During 1884-86, Lecturer on Chemistry at New
York Women's Medical College and Hospital for Women. At various times on
editorial staffs: of Scientific American, 1^8.'i-89; Independent CHI Journal, 1886, and on
technical subjecte in New York DaHy Nexcs, 1886 to date. New York Star, 1890-91
and Pharmaceutical Record, 1891, also of Appleton's Annual Cyclopadia since 1883.
Other work includes translation of Berthelot*s lectures on *' Explosive Materials"
(New York, 1883), authorship of Druggist* s Circular, Prize Essay on " Disinfectants,"
authorship of chapters on " Mineral Paints" in Mineral Resources of the United States,
for years 1884-86, and compilation of a book of Poems, entitled May Time (New York,
1889), and authorship of chapter on "Thomas Dongan and the Granting of the New
York Charter," 1682-1688, and '* The Development of Science in New York City," in
The- Memorial History of the City of New York^ 1892. Contributor to Scientific Amet^ican
and Supplement, The Chatauqnan, Harper's Weekly, Popular Science Monthly, The Cosmopol-
tton, etc. Life fellow of the London Chemical Society, and of the American Associa-
tion for the Advancement of Science, and member of other Scientific Societies in this
country and abroad. Member International Jury of Awards, World's Fair, Chicago,
1893.
Berry, Wilton Guernsey, Ph.B., .... 1886.
42 Bleecker Street, New York City.
1886-1889, Universities of Berlin and Heidelberg and General Chemical Research.
1889 to date, Assistant Chemist, New York Health Department.
— 20 —
Berry, George, C.E., 1888.
78 Morton Street, Brooklyn, N. Y.
BiEN, Joseph Rudolph, E.M., 1887.
140 Sixth Avenue and 321 West Fifty-seventh Street, New York City.
1887-88, Topographer, U. S. Geological Survey, Survey of Geyser Basins, Yellow-
stone Nat. Park. 1888-90, Piractice as Civil and Mining Engineer, firm of Vernieule
& Bien, Now York City. 1890-W, Practice as Civil and Tupograplileal Engineer
alone, New York City. At present, Secretary Julius Bien & Co., Lithographers, En-
gravers and Geographical Publishers.
Black, Alexander Leslie, E.M., .... 1890.
56 Carandelet Street, New Orleans, La.
1800-di, Traveling. 1891-92, Assistant in Mining-expert work in Montana and
Mexico. Since November, 1892-93, Assistant Superintendent Madeleine Consolidated
Mining and Milling Company.
Blake, Edwin Mortimer, E.M., Ph.D. (1893), . . 1890.
Fellow in Mathematics, Columbia College, New York City, and 230
Washington Avenue, Brook)>'n, N. Y.
Blossom, Francis, C.E., 1891.
Westinghouse, Church, Kerr & Co., 620 Atlantic Avenue, Boston,
Mas»., and 440 Henry St., Brooklyn, N. Y.
1891-92, Engineer with C. W. Hunt Co. 1892, Assistant Engineer Equity Gas Works
Construction Company. 1893, as above.
Blydenburgh, Charles Edward, A.B., A.M., E.M.,. . 1878.
Milling Expert and Prospector, Box 189, Rawlings, Wyoming.
BoDELSEN, Oscar, E.M., 1884.
Consolidated Gas Co., 1547 Broadway, and 309 W. One Hundred and
Twenty-seventh Street, New York City.
BcECKLiN, Werner, Jr., C.E., 1891.
Burlington, Iowa.
January to^Mny, 1893^ ran level en preliminary (150 miles), H. & E. Extension, C.
O. & S. W. Rsiilwayrin cbaige of all profiles and estimates under Chief Engineer.
Book, D wight Dana, C.E., E.E. (1892),. . . . 1890.
159 Washington Park, Brooklyn, N. Y.
BookjEM, Robert Elmer, M.E. (Life Member), . . 1878.
34 We»t lltk St., New York City.
tendent, afterward Manager, Evening l&tar Mining Co., Morning Star Consolidated
Farwell Con. M. Co., Gold Mines at Indepemlence, Colorado. 1887-90, General Man-
ager Blue Bird Mining Co., Ltd., Butte, Montana, Operating 90-Stamp Mill, Dry
Crushing, Chloridizing, Amalgamating Process. 1891, General Consnlting Mining
Engineer and Consulting Director in Gold, Silver, and Lead-Mining Companies, of
which a Specialty is made. Also Mine Operator and Owner, Silver Mines at Aspen,
Boyd, Richard Charles, Pn.B., A.M. (1892), . . 1891.
50 Charles St., New York City.
Bradley, Stephen Rowe, Jr., Ph.B., .... 1890.
392 Broadway, New York City, and Nyack, N. Y.
— 21 —
Jnly, 1891 to 1894, Secretary and Treasurer Union Electric Co. January, 1S94,
Secretary and Treasurer The Arlington Manufacturing Co., New York City.
Braschi, VicriX)R Manukl, Ph.B , E.M., C.E , . . 1881.
Apartado 830, City of Mexico, Mex.
June, 1884, to October. 1884, Inspector of New York Tenement House Commission.
October, 1884, to May, 1885, Interpreter and Sec'y to Gov. Chilian Commissioner to
Visit and Report on American Mining and Smeltini?. May, 1885, to October, 1885,
Employed by Rend-Rock Powder Co. in Flood Rock Explosion Work. October, lSi<5,
to January, 1889, Assistant ConsiiltiuK Engineer and in Charge Foreign Business,
Rand Drill Co. January, February, March, 1889, Reporting on Mines In Mexico for
above Co., and for three years, from April, 1890, to April, 1H93, engaged in intro-
ducing Rand Rock Drilling Machinery in Mexican mines. In April, 1893, arranged
to open a general Mining Machinery and Supply business, in the City of Mexico, in
which I am at present engaged.
Brereton, Thomas J., A.B., 1879, C.E , . . . 1883.
Engineer Cumberland Valley Railway, Chanibersburg, Pa.
1879, Rodman on Lo<ration of Redstone Br. P. R, R. IBvSO and 1881 (Summers) on
New York State Geodetic Snrvey of Adirondacks. 1883-85, Leveller P. R. R. Clear-
field Co. Surveys and Construction. On Corps of Engr. M. of W. P. R. R. 1888-89,
Assistant Supervisor, P. R. R. 1890-92, Supervisor Tyrone Div., P. R. R. 1893, En-
gineer Cumberland Valley Railway.
Brewster, Henry Draper (Associate), .... 1883.
Care Brewster & Co., 49th Street and Broadway, New York City.
Brinley, John Rowlett, C.E., 1884.
Morristown, N. J.
1884-88, Department of Public Works, New York City. 1888 to date, Civil and
Sanitary En^^ineer.
Britton, Nathaniel Lord, E.M., Ph D., . , . 1879.
Columbia College, School of Mines, New York City.
Assistant of Geology, School of Mines, 1879-1887. Instructor in Botany, Columbia
College, 1887-iaW. Adjunct Professor of Botany, Columbia College, 1890-1891.
Assistant, Geolojfical Survey of New Jersey, 1880-1887. Botanist, Geological Survey
of New Jersey, 1881-1890. Field Assistant, U. S. Geological Survey, 1882. Professor
of Botany, 1891. Specialty— Systematic Botany.
Brosn AN, Francis X A viER, C E. 1891.
146 W. Seventy-fourth Street, Now York City,
Brown, Francis G., E.M., 1867.
Merchant, 15 Whitehall Street and 462 Lexington Avenue, N. Y. City.
Browning, John H. Brower, M.D. (Associate), 1880.
10 W. Forty-third Street, New York City.
College of Physicians and Sargeons of City of New York, in year 1882. Afterwards
Assistant Physician, New York City Insane Asylum, Ward's Island, 1882-83. House
Physician and Surgeon to St. Francis Hospital, 1883-85. At date, Member County
Medical Society of New York, Member Physicians' Mutual Aid Association, Fellow
American Geographical Society, and Assistant to Chair in Surgery, New York Poly-
clinic, Medical Examiner for Presbyterian Board of Foreign Missions, General Prac-
titioner of Medicine and Surgery.
— 22 —
Brugman, William Frederic, Ph.B., .... 1880.
One Hundred and Forty-fourth Street and Southern Boulevard, New
York City, and Los Angeles, Cal.
Bryce, William, Jr:, Ph.B 1884.
40 W. Fifty-fourth Street, New York City.
Buckley, Charles Ramsay, A.B., A M., E.M., . . 1877.
Bdllman, Charles, Ph.B., 1883.
Editor The Safety Valve, New York City, and Plainficld, N. J.
1883. Tutor in Stoichiometry, Chemist Putnam Coinpaiiy Chemical Works. 1884-
1835-86, Venezuela; phosphates, copper, sulphnr. 1887, French Guiana; phosphates.
1888, 1889-90, North Odrolina, Georgia, Colomhia, S. A. (2) ; Rokl and platinum. 1891,
Sandwich Islands ; phosphates. California (2) ; gold and irrigation. 1892. New
Jersey; copper and graphite. \S^2-9^, Yi^\\lox^2^ ^ia,f^ Engineering and Mining Jour-
nal ; also Translator and Editor of Mining Laws of the Republic of CofontMa, and Author
of Platinum and South America in " The Mineral Industry."
Burden. Henry, 2cI., A.B., Ph.B., 1892.
Cazeuovia, N. Y.
Burns, Abraham Lincoln, E.M., 1887.
3 Worth Street, New York City, and 297 Halsey Street, Brooklyn, N. Y.
Since November, 1887, with Messrs. Jabez Burns & Sons (Millwrights and Machin-
ists, and Manufacturers of Patented Machines for Treating Coffee and Spices). Since
July, 1890, in above firm. Professional ^ork has been general shop draughting and
machine design, and arranging machines and power transmission in coffee establish-
ments.
Burns, Elmer Z., E.M., 1887.
Niagara Falls, N. Y.
1887-88. Engineer and Chemist for The Pittsbargh and Lake Angelioe Iron Co.
1889-90, Assistant Electrician for the United States Electric Light Company. 1890-
1891, Assistant Electrician for the Mather Electric Company. 1891-93. City Engineer
of Niagara Falls, and Consulting Engineer for the Lewiston and Youngstown R. R.
Company, for the North Tonawanda Street Rail Road Company, and for the Niagara
Falls and Suspension Bridge Rail Road Company.
BUKRITT, WiLMOT WoODWARD, Ph.B., .... 1884.
Chemist, Englewood, N. J.
Bush, Edward Renshaw, E.M., 1881.
Mining Engineer, with Ricketts & Banks, 104 John Street, N. Y. City.
BuTLER, Nathaniel, E.M., 1880.
51 Cedar Street, Koom 7, New York City, and Glen Ridge, Bloom-
field, Essex Co., N. J.
1880-1882, U. S. Harbor Improvement and Railroad Engineering. 1882-1894, Bar-
low's Insurance Surveys as Surveyor, Superintendent and Executive.
Butler, Wili^iam Curtis, M.E., 1887.
Everett, Washington, and 175 Hamilton Avenue, Paterson, N. J.
1887-iaS9, Assaycr. El Paso Smelting Co., El Paso, Texas. 1889-1890, Chemist,
afterward Assistant Superintendent; Arkansas Valley Smelting Co., Leadville, Colo.
1S90, Chemist, now Assistant Manager, Aurora Iron Mining Co., Superior Mining Co.,
— 23 —
Comet Mining Co., Palone Iron Mining Co., Penokee and Gogebic Development Co.
(Operating Colby and Tilden Mines). Also in charge Iron wood Electric Co., Qogebic
Electric Co. 1892, Superintendent Monte Cristo Mining Co., Seattle, Washington.
1893, Manager Pugct Sound Reduction Co.
Butler, Willard Parker, E.M.,LL.B. (Life Member), 1878.
Counsellor at Law and Solicitor of Patents, 59 Wall Street, New York
City.
o.
Cady, Lixus Bertram, E.M., C.E., .... 1877.
327 Fifth Avenue, New York City.
Calman, Albert, Ph.B., Ph.D., 1882.
332 W. Fifty-sixth Street, New York City.
Canfield, Augustus Cass, E.M., 1877.
Caxfield, Frederick A., A.B., A.M., E.M ., . . . 1873.
Mining Engineer, Dover, N. J.
Carson, James Petigru, E.M., 1868.
147 West Forty-second Street, New York City.
Casamajor, George H., C.E.,. ..... 1892.
East River Gas Co., 63d St. and Avenue A, New York City and 372
Greene Avenue, Brooklyn, N. Y.
Casey, Edward Pearce, C.E., Ph.B. (1888), . . 1886,
Arcliitect, 171 Broadway and The Alpine, 55 West Thirty-third
Street, New York City.
With McKini, Mead & White, architects. New York City, until January, 1890.
Abroad, and Student in L'Ecole National des Beaux Arts. Paris, from February, 1890,
until September, 1893. Five mentions in Architecture, and a medal in Modeling.
At present Architect, 171 Broadway, New York City.
Cauldwell, John BRrrxox, C.E., 1877.
Century Club, 7 West Forty-third Street, New York City.
Channing, John Parke, E.M., 1883.
Calumet, Lake Superior, Mich.
1883, Chemist Hudson River O. and I. Co. 1834, with S. E. Cleaves & Son, Manu-
facturers of Mining Machinery, Houghton, Mich. 1884-1885, Assistant Mining En-
gineer Tamarack Mine, Calumet, Mich., Dep. Comm. Mineral Statistics, Michigan.
1885-1886, Superintendent Honduras Land and Navigation Co. 1886-1887, Explor-
ing for iron on the Gogebic Range, and Mining Engineer for Milwaukee L. S. and
Western Railway, Superintendent Iron Belt Mine. 1887-1890, Inspector of Mines, Go-
gebic Co., Mich. 1890-1892, Superintendent East New York Iron Co.,Ishpeming, Mich.
1892 to 1893, Superintendent Iron Exploration, C, M. and St. P. Railway.
Chazal, Philip Edward, A.B., E.M., .... 1881.
68 Meeting Street, Charleston, S. C.
1881-1883, Prospecting in Northwest Georgia. 1883-1889, State Chemist of South
Carolina. 1889 to present* Partner in Shepard Laboratory, specialties Phosphate and
Fertilizer Analysis and examination and reporting on Phosphate lands [in South
Carolina and Florida).
— 24 —
Chester, Albert Huntingdon, A.M., E.M.,Sc.D., Ph.D., 1868.
Professor of General and Applied Chemistry, Rutgers College, and
64 College Avenue, New Brunswick, N. J,
Professor of Chemistry at Hamilton College from 1870 and Mineraloj?y from 1878
to 1891. Conducted the Analytical Laboratory there from 1871. Chemist New York
State Board of Health, 1882. Examined and reported on mines of iron, gold, silver,
fornia, and Nova Scotia. Analytical work has been largely in two lines, viz., for
iron-blast furnaces and of paints and varnishes. Field work has been, a great part
of it, in the iron mines of Minnesotti and the gold mines of Colorado.
Church, Elihu Dwight, Jr., E.M., .... 1887.
Church & Co., 36 Ash Street, and 127 Milton Street, Brooklyn, N. Y.
1887-1888, Fellow Qualitative Analysis, School of Mines. 1888-1889, Assistant Su-
perintendent of Lead Mine and Concentrating Works. 1889-1891, with Church & Co.,
in charge of experimental plant.
Church, John Adams, A.M., E.M., Ph.D , . . . Ift67.
Corn Exchange Building, 11 William Street, New York Cit}-. Cable
Clark, Diego Lombillo, C.E., 1890.
Cardenas, Cuba.
Clark, Edmund (Associate), 1892.
Clark, Edwin Perry, E.M., 18S0.
Title Guarantee and Trust Co., 26 Court Street, and 425 Fifth Street,
Brooklyn, N. Y.
1880-1883, Engineer and Surveyor for Silver-Cord Combination, and Robert E. Lee
Mining companies. Lead ville, Colo. 1883-1834, Medical student. 1884 to date, Assist-
ant Superintendent and afterwards Superintendent Title Guarantee and Trust Com-
pany, 55 Liberty Street, New York, and 26 Court Street, Brooklyn. In charge of
eonstruction and maintenance of locality-indexes of Rsal Elstate Records of New
York, Kings and Westchester counties, N. Y.
Clark, Franklin Sinclair, E.M., Ph.D., . . . 1885,
Carolina Oil and Creosote Co., Wilmington, N. C, and 627 Madison
Avenue, New York City.
1835-1887, Chemist to Fernoline Chemical Co., Charleston, S. C. 1887 to date, Pro-
prietor of Southern Chemical Works and consulting chemist for the Carolina Oil and
Creosote Co., Wilmington, N. C. Specialty, Distillation of Wood and refining products
and crcosoting wood.
Clark, George Hallett, C.E., 1893.
59 E. Sixty-seventh Street, New York City.
1893-94, Transitman Metropolitan Traction Co., Lexington Ave. C*able Construction.
Bethlehem Iron Co., South Bethlehem, Pa.
1881-1883, Assistant to Prof. C.F. Chandler on New York State Board of Health Bu-
reau of Chemical Analysts. 1883-1886, Instructor in Quantitative analysis and Chem-
ical Philosophy in the Lehigh University, South Bethlehem, Pa. 1886-92, Head
Chemist of the Bethlehem Iron Co. 1893 to date, Metallurgical Engineer same Com-
pany, South Bethlehem, Pa. Specialty, Metallurgy of Iron and Steel.
— 25 —
Colby, Charles Edwards, E.M., C.E., , . . . 1877.
Adj. Professor Organic Chemistr}', Columbia College School of Mines,
New York City.
Cole, Harold Morris, E.M., C.E., .... 1887.
Care of Helena & Livingston S. & R. Co., Wickes, Montana.
21 W. Park Street, and 57 Broad Street, Newark, N. J.
1873-1882, Assistant in Mineralogy, School of Mines. Columbia Collojfe, New Yotk.
1882-1884» Professor of Chemistry and Mineralogy, Rose Polytechnic Institute, Terre
Haute, Indiana. 1884 to date, Director and Instructor in Chemistry and Physics,
Newark Technical School.
CoNANT, Henry Dunning, E M., 1886.
iP. O. Box 16, Mount Vernon, N. Y.
1886-1888, Assistant Engineer Tamarack and Osceola Mines, Lake Superior, andH.
and C. R.R. 1888-1889, Assistant Engineer on Preliminary of Northern Michigan
Railroad. 1889, Assistant in Chief Engineer's OfSce, Buffalo and Qeneva Rail-
way. 1889-91, Assistant and Resident Engineer Norfolk and Western Railroad, in
charge of Preliminary Location and Coustruction. 1891, Engineer Coeburn Land and
Improvement Co. 1893, Assistant Engineer N. Y., N. H. & H. Ry.
CoNGDON, Ernest Arnold, Ph.B., F.C.S., . . 1887.
Professor of Chemistry, Drexel Institute Arts, Science and Industry,
and 1336 Spruce Street, Philadelphia, Pa.
1887-1889, Chemist to Champlain Fibre Co., Willsborough, New York. 1889, Studied
at the University of Berlin, Summer Semester. 1889 to date, Instructor in Quali-
tative Analysis and Assaying at the Lehigh University. 1891, Professor of Chemistry
in the Drexel Institute of Arts, Sciences and Industries, Philadelphia, Pa.
CoNNELL, Hewlett Ratjston, C. E., . . . 1890.
140 Pierrepont Street, Brooklyn, N. Y.
Cooper, William Hamilton, Ph.B. (Life Member), . 1882.
Corcoran, John Thomas, E.M., S.E., .... 1884.
131 Smith Street, Brooklyn, N. Y.
Cornell, George BiRDSALL, E.M., C.E., . . 1877.
29 Broadway and 46 West Fortyei^rhth Street, New York City.
Assistant Engineer Manhattan Elevated Railway. Engineer for Contractors for
structure Manhattan Elev. Ry. Assistant Engineer Brooklyn Elev. Ry. Assistant
Engineer New York, Chicago and St. Louis R. R. Pnncipal Assist. Engineer Roch-
ester and Pittsburgh Ry. Inspector and Engineer Bridge Dept. N. Y., West Shore and
Buffalo Ry. Principal Assist. Engineer Brooklyn Elevated Ry. Chief Engr. Brook-
lyn Elev. Ry. Chief Engr. Union Elevated Ry.of Brooklyn. Chief Eng. Chicago and
South-side Elev. Ry. Chief Engr. J. B. & J. M. Cornell Iron Works. At present Chief
Engineer East River Bridge Company.
Cornwall, Henrv Bedinger, A.B., A.M., E.M., Ph.D., 1867.
Professor Analytical Chemistry and Mineralogy, College of New Jer-
sey, and 51 Nassau St., Princeton, N. J.
Cornwall, Harry Clay, E.M., 1879.
Commonwealth Insurance Co., Nassau Street, New York City.
— 26 —
Cox, Jennings SrocKTox, Jr., Met. Exg., . . . 1887.
Everett, Washington, and 76 W. Sixty-eighth St., N. Y. City.
1887, Government Survey for Canal between Harlem and Hndson River. 1888-1889,
Homestead Steel Works, Dranglitsraan and afterward Assistant Master Mechanic.
1890, Inspected construction of Steamer "Sezurania" and " Vigilancia" for the U. 8.
and B. M. S. S. Co., at Roach's Shipyurd, Chester, Pa. 1891, Reporter for same Com-
pany on Engineering: matters along the Brazil coast. 1892, with same company in
New York. 1892, Assist't Superintendent Aarora Iron-Mining Company, Ironwood,
Michigan. 1893, Assist. Supt. Monte Cristo Mining Co., Pride of the Monntain Mining
Co., Rainy Mining Co., and United Concentration Company.
Cram KR, Stuart W., E.M. (Associate), .... 1889.
Charlotte, N. C.
Graduate of United States Naval Academy; resigned from the United States Navy
September, 1888. Graduate student at S(*.hool of Mines, 1888-1889. Assayer in charge
of the United States Assay Office, Charlotte, N. C, 1889-93. Special agent for col-
lection of statistics on gold and silver for the Southern States, 1890. March 10, 1893,
to present time, Engineer and Chemist for the D. A. Tompkins Company, General
Engineers and Contractors, of Charlotte, N. C. Special correspondent of Enffineering
and Mining Jounuil. Specialty: Westinghouse system of electric lighting and trans-
mission of power.
Crocker, Francis Bacon, E.M., ..... 1882.
Prore8.sor Electrical Engineering, Columbia College School of Mines,
and 26 W. 22d Street, New York City.
1882-iaSO, Electrical Engineer and Inventor. 1886-1887, Vice-President and Elec-
trician of "C. and C." Electric Motor Co. 1887-1889, Vice-President and Electrician
Crocker-Wheeler Electric Motor Co. 1889-92, Instructor in Electrical Engineering,
School of Mines, Columbia College. 1892, Adj. Professor. 1893, Professor.
Crowell, Charles Burton, Ph.B., 1885.
Minneapolis, Minn.
CusHMAN, Alexander Ramsay, Ph.B., Ph.D., , . 1878.
Assistant Analytical Chemistry, Columbia College School of Mines,
and 128 E. Sixteenth Street, New York City.
1878-1880, Post Graduate study at the School of Mines, for degree of Ph.D. 1880-
1882, in Colorado, visiting mines and smelters. 1832-1890, Engaged in pursuing
chemical studies and lecturing on geology. 1890 to date, Assistant Instructor in Quali-
tative Laboratory at the School of Mines, Columbia College.
D.
Darwin, Harry Gilbert, C.E., 1887.
Room 23, 160 Broadway, New York City, and Gien Ridge, N. J.
June, 1887 to October, 1887, Rodman and Leveller on Railroad field work in New York
State. October, 1887 to May. 18SS, Draujchtsmau Strong Locomotive Co., New York
City. August, 1888 to date, Assistant Engineer and Acting Superintendent Safety
Car Heatinv and Lighting; Co., New York City. Erection of special gas works, and
Davis, Charles Henry, C.E., .... 1887.
576 Lexington Avenue, New York City.
— 27
Expert course and Thomson- Honston Electric Co., Lynn, Mass., summer 1887.
Agent, Lawyer Mann Electric Co., winter 1887-88. Supt. selling and construction
New York office S. M. Elec. Co., summer and winter 1888. Agent Westinghouse
Electric Company, winter 1889. Consulting and Supervising Electrical Engineer
from May, 1889, to date.
Davis, John Woodbridge, C.E., Ph.D., .... 1878.
Principal Woodbridge School, 417 Madison Avenue, New York City.
Deghu^e, Joseph Albert, Ph.B., A.M. (1892), Ph.D.
(1893) 1890.
College Phvs. and Surg., New York Citv, and 247 Harrison St., Brook-
lyn, N. Y.
Assistant Demouitrator in Physics and Chemistry, College of Physics and Surgery.
Delafiei.d, Augustus Floyd, Ph.D. (Associate), . . 1869.
University Club, New York City.
De LuzK, Ijouis PHiLrppR, C.E , 1879.
DeLuze & Enimett, Engineers and Surveyors, New Rochelle, N. Y.
Dexton, Frederick Warxer,,C.E., .... 1884.
Institute Civil and Mining Engineers, Houghton, Mich.
Devereux, Walier Bourchier, A.B., A.M., E.M., . 1878.
Dodge, Frank Despard, Ph.B., Ph.D., . . 1888.
Dodge & Olcott, 137 Water St. and 111 Montague St.Brooklyn, N. Y.
From October, 1891, to date, Chemist, with Dodge & Olcott, manufacturers of es-
sential oils, etc. 188S-90, Fellow in Chemistry, Assistant in Organic Laboratory
School of Mines. 1890-91 (studying in Germany).
Dodsworth, Walter Albert, Ph.B., . . . • 1888.
19 Beaver Street, New York City, and 253 Henry Street, Brooklyn,
N. Y.
With Journal of Commerce and Commercial Bulletin.
DoLAN, Charles Francis, C.E., 1392.
Ill East 129th Street, New York City, and Department Street Im-
provements, 2622 3d Avenue cor. 141st Street.
1892-93, United States Inspector of Dredging Operations, Harlem Slip. Canal and
Newtown Creek. 1893 to date, with Department of Street Improvements, New York
City.
DoNNELL, Harry Ellingwood, Ph.B., . . . . 1887,
Douglas, John Sheafe, C.E., 1890.
Union Elect Company, 45 Broadway and 72J Irving Place, N. Y. City.
1890, Course Electrical Engineering, Columbia College. 1891, Crocker- Wheeler
Electric Motor Company, and now Assistant Engineer Western Electric Company in
Lighting Department. 1893, Superintendent of Union Elect. Co.'s Exhibit at World's
Columbian Exposition, Chicago.
Douglass, Edwarh MoREHousEJ, C.E., . . , . 1881.
Topographer U. S. Geological Survey, Washington, D. C.
— 28 —
Dow, Allan Wade, Ph.B. (Life Member), . . 1888.
Care The Barber Asphalt Paving Company, fjot of 4Gth St., Long
Island City, N. Y.
1888-89, Honorary Fellow Quant. Laboratory. School of Mines. 1889, Chemist at
Tilly Foster Mine, New York. 1839-91, Assistant Chemist of The Barber Asphalt
Paving Co.
DowNES, Stancliff Bazen, C.E., 1882.
1071 Madison Avenue, New York City.
December, 1882. to April, 1885, Assistant, Office Topojrraphical Engineering De-
partment Public Parks. New York City. April, 1885, to January, 1891, Assistant
Engineering Deixartnient Public Parks. April, 1886, elected Junior Member American
Society Civil Engineers. January, 1891, to date, Civil Engineer, Fonlham, New York
Downs, William Fleicheu, E.M., .... 1882.
Joseph Dixon Crucible Co., and 75 Fairview Avenue, Jersey City, N. J.
With the Joseph Dixon Crucible Co. since graduation. From June, 1882, to Sep-
tember, 1882, at experimental work. From September, 1882, to October, 1884, in
charge of lubricating department. From October, 1834, to present time Superinten-
dent of crucible and other departments. *
Dresser, Daniel LeRoy, C.E., 1889.
Merchant, 273 Church St., New York City, and Flushing, N. Y.
Drummond, Lsaac Wyman, E.M., Ph.D., . . 1878.
F. W. DeVoe & Co., William and Fulton Streets, New York City.
DuFOURCQ. Edward Leonce, M.E., .... 1892.
846 Lexington Avenue, New York City. *
1892-93. Assistant Superintendent Cost}\Rica Pacific Gold Mining Company, Puuta
Arenas, Costa Rica. Summer of 1893, Assistant in Mining, Columbia College and
Transitman for J. F. Carey & Co., Brooklyn. November, 1893, Assistant Engineer,
Mazapil Copper Company, Concepcion de Oro, Zacatecas. Mexico.
Dunham, Eqward Kellogg, Ph.B 1881.
338 East Twenty-sixth Street, New York City.
Professor of Pathology, Bacteriology and Hygiene iu the Bellevue Hospital Medi-
cal College, New York City.
DusENBERRY, Walter Lorton, E.M., .... 1884.
Department Public Works and 361 Produce Exchange, New York
City.
1884-87, miscellaneous. U. S. Coast Survey. Mining in Mexico and the west.
Survey of New Parks, Westchester County, etc. 1887--89, Inspector of Masonry and
Transit-man on New Croton Aqueduct. 1839-91, in charge of party and Assistant
Engineer of Construction Department of Public Parks, New York City.
DuTCHER, Basil II., Ph.B., 1892.
525 Manhattan Avenue, New York City.
Summer of 1890, on Reconnaisance Survey iu Idaho and Nevada, Biological Survey,
U. S. Department of Agriculture. Summer of 1891, on Death Valley Survey, Cali-
fornia, U. S. Department of Agriculture. Summer of 1892, Biological Survey, U. S.
Department of Agriculture, in Kansas, Oklahoma, Texas, New Mexico. Winters,
1892-93 and 1893-91, Student, College Physicians and Surgeons, Columbia College.
— 29 —
DwiGHT, Arthur Smith, E.M., 1885.
1885, Assistant Assayer at works of The Colorado Smelting Company, Pueblo,
Colorado. 1885 to 1888, Assistant Chemist and Chemist, except autumn of 1886, when
examining and reporting on lead deposits of Coeur d'Alene region, Idaho Territory,
and spring of 1889, when acting as Assistant Snpt. Madonna Mine, Monarch, Colo.
1888-90, Metallurgist, and 1890 ta date. General Supt. of the Colorado Smelting Co.
E.
Easton, Langdox Cheves, C.E., 1884.
Port Harford, San Luis Obispo Co., Cal., and 344 Soutli Grand Avenue,
Los Angeles, Cal
1885-88, Engineer Corps, Aqueduct Commission, New York City. 1889, City Sur-
veyor's Corps, Los Angeles, Cal. 1869 and 1891, in charge of harbor improvements,
Port Harford, Cal., under direction of U. S. Corps of Engineers.
Eastwick, George Spencer, C.E., 1879.
Manager American Sugar Refinery Co., 24 North Peters St., New Or-
leans, La., and 1425 Broadway, New York City.
Eastwick, Edward Peers, Jr., Ph.B., S.E., C.E. (1892), 1889.
Care of American Sugar Refining Company, New Orleans, La.
Eberhardt William G., M.E., 1891.
Richardsville, Culpepper Count}', Virginia ; 450 W. Twenty second St.,
New York City.
Eddie, Edward Crittenden, E.M., .... 1885.
Colorado Smelting Co., Box 8, Pueblo, Colo.
Edwards, Richard Mason, E.M., 1886.
Red Jacket and Houghton, Mich.
1886-87, general assay office at Hooj^hton, Mich. 1888-89, Professor of Mining,
Michigan Mining Scliool, Houghton. 1890 to date, Mining Engineer for Tamarack,
Tamarack, Jr., Osceola and Kearsarge Mining Cos., L. S., Mich.
EiLERs, Karl Emrich, E.M., ...... 1889.
Care of Colorado Smelting. Co., Pueblo. Col, and 751 St. Mark's Ave-
nue, Brooklyn, N. Y.
1889-91, student and travelling in Europe.
Elliott, Arthur Henry, Ph.B, Ph.D, . . . 1881.
4 Irving Place, N. Y. City, and Peekskill, N. Y.
Professor Chemistry and Physics, New York College of Plmrmacy. Chemist to
Consolidated Qas Co. Editor Anthony's Photographic Bulletin. Author A. H. Elliott's
Qualitative Chemical Analysis.
Elliott, William, Ph B., 1880.
56 Wall St., New York City.
Engel, Louis George, E.M., 1880.
Brooklyn Sugar Refinery, American Sngar Refining Co., and 238 Cler-
mont Avenue, Brooklyn, N. Y.
Three years, Tilly Foster Iron Mine (E. M.). Ten years, Brooklyn Sugar Refinery.
Engelhardt, Eugene Nicholas, E.M., . . . 1885.
Selby, Contra Costa Co. , Cal.
— 30 —
1886, Assaycr, Chemist and Assistant Superiutendent Pueblo Smelting and ReAning
Go. 1887 and 1888, Superintendent of the same company. 1889, Assistant Superin-
tendent Anaconda Smelting Co. From 1890 and to present time, Assistant Snperiuteu-
deut Selby Smelting and Lead Co.
P.
Fahys, Gkoroe Ernest, C.E., 1884.
38 Maiden Lane, New York City, and 285 DeKalb Avenue, Brooklyn,
N. Y.
Treasurer, Prentiss Calendar Time Co.
Falk, David Beauregard, C.E., 1882.
Savannah, Ga.
Fearn, Percy Le Roy, E.M., 1889.
1889-90, Assayer and Surveyor, Trinidad Mine, Costa Rica. 1890-92, Superintend-
ent, Trinidad Mine, Costa Rica. 1892-93, Consulting Mining Engineer Illinois Fluor
Ferguson, William Cushman Augustine, Ph.B., . 1887.
Nichols Chemical Co., Laurel Hill Chemical Works, Laurel Ilill, N. Y.,
and 520 Nostrand Ave., Brooklyn, N. Y.
From 1887 to 1888, Chemist, Fulton Sugar Refinery. From 1888 to date (1891),
Chemist for Nichols Chemical Co., Manufacturers of Sulphuric, Muriatic and Acetic
Acids, Alum, Salt Cake, Bisulphate Soda, Blue Vitriol, and Smelters of Copper Ore;
also Manufacturers of Acid Phosphate^ Work : Investigation of different questions
affecting above, and also in new lines, such as Sulphate of Alumina, etc. Also ana-
lytical work.
Ferrer, Carlos Ferrer, C.E., 1883.
39 Broad Street, New York City.
After graduation, for a few weeks on work at the School of Mines. Then under
Mr. W. £. Worthen, C.E., on some work for the Water Commissioners of the State of
New Jersey. From March, 1H84, to January, 1887, on the Engineering Corps of the
Aqueduct Commissioners, New York City, as Assistant to Engineer of Construction ;
Leveler in charge of field work on Section " A "; reduced to Rodman in charge of
same; promoted to Assistant Engineer: resigned in January, 1887, and have since
Ferris, Junius Colton, E.M., 1883.
Carthage, III.
Feuchtwanger, Henry, Ph.B., 1882.
Room 19, 99 Franklin Street, New York City.
FiALTX)s, Enrique Constantino, C.E., .... 1883.
No. 27, Calle lOa, Tegucigalpa, Honduras, C. A., and care Ernest
Scl-.ernikow, P. O. Box 3540, N. Y. City.
General practice in Engineering. Professor of Mathematics and Mineralogy in the
University of Tegucigalpa. The most extensive practice has been, as Government
Surveyor of Lands and Mines. '
Fl&HER, WiLLARD, E.M., 1888.
361 W. Fifty-sixth Street, New York City.
Draughtsman to Parsons, C.E., New York City. Assistant to Superintendent
Segovia Gold Mining Co., Nicaragua. Clerk, Office of Rich Hill Coal Mining Co.,
— 31 —
Rich Hill, Mo. Engineer and Mine Surveyor, Rich Hill Coal Mining Co., Rich Hill,
Mo. Prospecting for coal, Southwest Missouri, along the line of Wicliilnw & Western
in the interest of the Missouri Pacific Railroad. Soutliern Sales Agent, Coal Cos. on
the lines of Missouri Pacific Railway. President Tyler S. E. Railway of Texas.
Floyd, Frederick William, C.E., E.M., . . . 1877.
539 W. Twentieth St. and 175 W. Eighty-seventh St., N. Y. City.
1877-78, Honorary Assistant in Metallurgy, Scliool of Mines. 1878-81, U. S. Geo-
graphical Surveys, West of 100th Meridian. 1881-82, Preliminary Surveys, New
Croton Aqueduct and Dam, New York. 1882, Reporting on Mines in Colorado. 1883
to date, Firm of James R. Floyd & Sons, Iron Works. Specialty, Gas Engineering
and Gas Works Construction.
Foster, Reginald Guy, C.E , 1893.
16 E. Thirty-first Street, New York City.
Fowler, Albert Casimik, C.E., 1889.
Cienfuegos, Cuba.
Fowler, Samuel Stewart, A.B., E.M., .... 1884.
Golden, British Columbia, Canada, and Room 201, 34 Clark Street,
Chicago, 111.
1885, Civil Engineering Work, New York. 1880, Assistant Superintendent, Iron
Hill Mining and Milling Co., Black Hills, South Dakotiv 1887, Assistant Superin-
tendent Galena Reduction Co., Black Hills, South Dakota. 1888, Superintendent,
International Smelting Works, Textis. Engineer and Assayer, Bunker Hill and Sul-
livan Mg. and Cone. Co., Idaho. 1889, Reporting sundry properties. 1890 to date,
Superintendent Golden Mining and Smelting Co., Golden. B. C, Canada. Deputy
Commissioner World's Columbian Exposition, 1893.
Foy£, Andrew Ei^nest, C.E., 1890.
Tutor in Civil Engineering, Scliool of Mines, Columbia College, and
163 West Seventy-ninth Street, New York City.
1890-92, Engineer's ofllce, M. W. P. R. R. 1892 to date, as above,
Frank, Jerome William, Ph. B, 1888.
Standard A^arnish Works, 207 Avenue D, New York City.
Freedman, William. Horatio, C.E., .... 1889.
41 E. 49th Street, and 120 W. One Hundred and Twenty-fifth Street,
New York City.
Post-graduate in Elect. Engineering, 1889-91. John Tyndall Fellow, 1891-92. Tu-
tor in Elect. Engineering, since 1892. Additional degree of E. E. in June, 1891.
Friedman. Samuel, C.E., 1892.
Tuscaloosa, Ala.
Furman, Howard Van Fleet, E.M , .... 1881.
U. S. Mint, Denver, Col.
1882-88, Assayer and Chemist and Foreman, German ia Lead Works, Utah. Chem-
ist, Globe Smelting and Refining Co., Denver. Assistant Superintendent, Billings
Smelter, Socorro, New Mexico. Superintendent, Bailey Smelter, Denver, Colo. 1888-
91, some experience as Consulting Engineer and Metallurgist. 1894, Chief Assayer
U. S. Mint, Denver, Colo.
G.
Garlichs, Herman, E.M., . . . . . . 1880.
Omaha and Grant S. and R. Co., Omaha, Neb.
— 32 —
1880-83, Flarveying and Reporting on Mines in Colorado. 1883-87, Assistant Super-
intendent, Aurora S. & R. Co., Aurora, III. 1887, and to the present. Superintendent,
Refining Department, Omaha and Grant S. and R. Co. Special ty. Silver and LfOad
Smelting and R'^fluing.
GiFFORD, Stanley Devol, E.M., 1889.
Butte City, Montana, and Tuckalioe, N. Y.
Going, CuARLEs Buxton, Ph. B., 1882.
President Cincinnati Desiccating Co., Cincinnati, and Glendale, Oliio.
GoLDSCHMiDT, Samuel Anthon y, A.B., A.M., E.M., Ph.D.
(Life Member), .1871.
Treasurer Columbia Chemical Works, 43 Sedgwick St. , Brooklyn, N. Y. ,
and New York Cit}'.
Assistant Ohio Geological Survey, 1871. Chemist and Assistant Inspector of Fer-
tilizers, Savannah, Ga., during winters of 1871-75. During summers, Assistant to
Dr. Chandler, Inspector New York Board of Health, 1873-75. Reporting on Guano
Islands, South Pacific, 1876. General Consulting Pnu-tice, 1876-80. Inspector Of-
fensive Trades, New York Board of Health, 1879-88. Treasurer and Manager Colum-
bia Chemical Works, 1880 to date. Specialty, Ammonia Manufacture.
Good, George McClelland Houtz, E.M., . . . 1886.
Mining Engineer, Osceola Mills, Clearfield Co., Pa.
1892, Mining Engineer to The United Collieries Company. 1893, Assistant Gcn'l
Manager of the same.
G(K)DWiN, Edward, E. M., 1891.
Harte, Shasta Co., Cal., and Governor's Island, N. Y.
Gordon, John, Jr., E.M., 1871.
G. O. Gordon, 69 Wall St., N. Y. City.
Merchant, Edward Johnston <& Co., 62 Sas Pedro, Riode Janeiro, Brazil.
Gosling, Edgar Bonaparte, E.M., C.E, . . 1884.
Windsor Hotel, New York City.
Tutor in Mathematics, Columbia College from 1884 to 1885. Draughtsman and
afterwards Assistant Engineer in Department of Docks, New York City, 1886-88. In
Manufacturing Business in Paris, France, 1888-89. Tutoring in Mathematics and
Engineering Branches in New York, and Superintending building of houses, intro-
ducing Culm-burning Furnace in U. S., 1889-91. In charge of erection of buildings in
artificial stone (Betou Coignet), for the Suez Canal Company. Egypt.
Graff, Charles Everett, EM., . . ' . . 1885,
50 Highland Avenue, Jersey City, N. J.
1885-87, Assistant Engineer, Central Entre Riano Railroad, Argentine Republics.
A. 1887-88, Engineer, Arizona Union Mining Co., Prescott, Arizona. 1888-90, Manu-
facturing Work, Binding Twine and Reapers. 1890-91, Engineer, Eagle Oil Co.
Gratacap, I/OUis Pope, Ph.B., 1876.
Curator American Museum Natural History, New York City, and West
New Brighton, S. I.
Greenleaf, James Leal, C.E., . . . . 1880.
Adj. -Professor Civil Engineering Columbia College Sphool of Mines,
and Llewellyn Park, West Orange, N. J.
Special Agent for Tenth Census for Water-power from 1880 to 1882, Since instruc-
— 33 —
ting in engineering, civil and sanitary, in Soliool of Mines, Colnmbia College. 1891,
Adjunct Professor Civil Engineering, Columbia College.
Griffin, Samuel Palmer, Jr., E.M., .... 1884.
Building Dept., Eighteenth St. and Fourth Ave., and 449 Paik Ave.,
New York City.
Griswold, WiLLfAM Tudor, C.E., . . . . . 1881.
U. S. Geological Survey, Washington, D. C, and Boise City, Idaho.
Gross, Louis Nathan, B.S., E.M., 1884.
Merchant and 38 East Fifty-eighth Street, New York City.
Gudeman, Edward, Ph. B., Ph.D., 1887.
Peoria Grape Sugar Co., Peoria, 111., and P. 0. Box 3001, N. Y. City.
Student at the Universities of Berlin and Gottingen, 1887-80. Private Assistant
with Dr. C. F. Chandler, and Honorary Assistant at the School of Mines. 1869
and 181K), Professor of Chemistry in charge of the Department of Chemistry, Dyeing
and Pottery at the Pennsylvania Museum and School of Industrial Art, Philadel-
phia, Pa. 1890-92, Chemist with the American Glucose Company at Bufl'alo. N. Y.,
and Peoria, 111. 1892-93, Chemist in charge of Peoria Grape Sugar Company, at
Peoria, 111.
GuDEWiLL, Charles Edward, C.E., .... 1890.
P. 0. Box 921, Montreal, Canada.
GuiTERMAN, Edward Wolf, Ph.B., . . 1889.
Passaic Print Works, Pas.saic, N. .1., and 335 West Fifty-eighth Street,
New York City.
1890 to date, Chemist above works.
H.
Haa^is, Dunbar Ferdinand, E.M., .... 1883.
U. S. S. '' Gedney," Box 173, and 83 Rector St., Perth Auiboy, N. J.
1883-84, Inspector of bridge work, Stony Point, New York. 18S5-88, Assayer and
Chemist, afterwards General Manager Parral Mining and Milling Co. (silver), Mexico.
1889, with Corps of Engineers, U. S. A., on New York Harbor Improvements. 1890
to date. Engineer Marion Phosphate Co., Florida, and Engineer Hamburg Phosphate
Co., Florida. Surveying, prospecting and reporting on phosphate deposits. 1892-93,
with U. S. Engineers in charge construction Concrete Fortifications. In charge of
Harbor Improvements. Assistant Engineer of Dominion Construction Company for
pipe laying and Riservoir engineering.
Haffen, LouiS Francis, A.M., C.E., .... 1879.
Conjmij<sioner Street IniprovcmeiUs. One-Hundred and Forty-first St.
and Third Ave. and 047 Corllandt Ave., 23d Ward, N. Y. City.
Hale, Albert Ward, A.B., A.M., E.M., . . 1867.
Department Public Works, East Twenty-fourth Street, and 81 Clinton
Place, New York City.
Hall, Robert William, E.M., 1876.
University Building, Washington Square, New York City.
Trom 1879 to 1888, Chemist to the American Gas Fuel and Light Company and to
some associated companies. Since the autumn of 1888, Acting Assistant Professor of
General Chemistry in the University of the City of New York. Since the autumn
of 1890, also Acting Professor of Analytical Chemistry in the same institution. 1891,
Professor of Analytical Chemistry, same institution.
3
— 34 —
Hallock, Albert Peter, Ph.B., Ph.D., . . • 1880.
440 First Avenue and 434 Lenox Avenue, New York Cit.v,
June, 1880, to October, 1880, with Dr. P. de P. Ricketts. October, 1880, to Novem-
ber, 1897, Chemist Consolidated Gas Co. November, 1887, to January, 1889, in the
shell lime business. January, 1889, to date. Chemist to Carl H. Schultz, Mineral
Water Factory. Specialty, Gas and Mineral Water Chemistry.
Hankinsox, Albkrt Wouthington, C.E., . . . 1893.
114 West Forty.fifth Street, New York City.
Hanna, George Byron, A.B , E.M., .... 1868.
Charlotte, N. C.
Chemist and Assistant Geologist North Carolina Geoloji^ical Survey. Melter and
Assistant Assayer U. S. Assay Office, Charlotte, N. C. Also Consulting Mining Engi-
neer and Chemist, etc.
Hakding, George Edward (Associate), . . . . 1867.
Architect, Postal Telegraph Building, New York City.
Harrington, Thomas Henry, C.E., .... 1889.
Westchester, Westchester County, N. Y.
July, 1889, to March, 1893, Inspector Clerk and General Superintendent on U. S.
Works, Flood Rock, Hell Gate, East River, N. Y. April, 1893, in charge of Exhi-
bit of River and Harbor Improvements from New York City and Hudson River,
at World's Columbian Exposition, Chicago.
Harris, Edwin, A., Ph.B., 1889.
Secretary and Treasurer, Globe Steam Heating Co., 412 N. Eleventh
Street, St. Louis, Mo.
1889-90, Chemist of the Camden Consolidated Oil Company. 1890 to date, Cliemist
Camden Consolidated Oil Company and agent for oil, mineral and timber lands in
West Virginia and Ohio. Chemist to the Phosphorus Works of J. J. Allen's Sons, 2
Harte, Charles R., ..:... . 1893.
Box 136, Milford, Conn.
915 Delaware Avenue, Wilmington, Del.
Hathaway, Nathaniel, Ph.B., 1879.
Swain Free School, and 43 Elm Street, New Bedford, Mass.
1879-80, Booth and Etlgar Sugar Refinery. 1880-83, Private Assistant to Dr. E.
Waller, Now York. 1883-91, Teacher of Chemistry and Physics Swain Free School,
New Bedford, Mass., and general analytical work.
Hawley, John Francis, C.E., 1891.
HUBERT, Octave Britton, C.E., 1888.
72 W. f)9th Street, New York City.
Heinsheimer, Alfred Maurice, C.E., .... 1887.
Kuhn, Loeb & Co., 30 Nassau Street, and 71 East Ninetieth Street,
New York City.
Hendricks, Henry Harmon, Ph.B. (Life Member), . 1880.
Hendricks Bros., 49 Cliff Street, New York City.
— 35 —
Herckenrath, Walter Augustus, A.M., CE^ , . 1892.
University of Ottawa, Ottawa, Ontjwio, "Canada.
1892-93, Erie City Iron Works and with City Engineer on pavements and sewei-s;
Wilmington, Vt., on Railway and General Engineering; Inspector U. S. Dredging
Operations, Gowanus Bay. At present temjwrari^y employed in tbemathematical
Department of the University of Ottawa.
Hewletf, James Monroe, Pn.B., . . . . . 1890.
McKiiD, Mead & White, I W. Twentieth Street, and ^8 Remseci St.,
Brooklyn, N. Y.
Hildreth, Russell Wadsworth, E.M^ . . . 1886.
R. W. Hildreth & Co., Inspecting and Civil Engineers, Specialty Bridge
Works, No. 2 Wall Street, amd 25 Madison Avenue, New York City.
Hildreth, Walter Edwards, C.E., E.M., . . , 1877.
Metropolitan Hotel, 584 Broadway, New York City,
Hill, William, C.E., 1882.
Assistant Superintendent -Collins Company, Box 196, CJoHinsville,
Conn.
One year practical experience in mannfactureof crucible steel. Two years draughts-
man and assistant to master mechanic'of conipany manufacturing crucible steel, bar-
iron, edge tools, plows and wrenches. Engineer in charge of reconstruction of dam
600 feet long, 32 feet high, at Otis, Mass. 1886 to date, Assistant 'Superintendent for
the Collins Company, maiHifacturing principally edge tools. November 1st, 1891,
appointed agent of the Collins Company, with general charge of j)lant at CoUi<isville
Conn., employing 650 men.
HiNMAN, Bertrand Ciiase, Ph.B., A.m. (1892), . 1890.
929 Flushing Avenue, Brooklyn, and Mansville, Jefferson County,
N. Y.
Since Jane, 1890, Chemist to .the Iron Clad ManufactHring Company, engaged in
the mauafactnre of sheet-iron enamelled ware.
HoLBR(H)K, FRA^'CI8 ^'ewberry, C E., . , . . 1876.
• 42 Pine Street, New York City, and Box 395, Tarrytcrwn, N. Y.
From &11, 1876, to spring, 1880, Assistant Assay Laboratory School of Mines.
Spring and Summer-on Geological Survey, West Texas. Then to 1881, spring, Super-
intendent Corralitos Co., Chihuahua, Mexico. 1884-87, expert work, office El Paso,
Texas. Summer and fall, 1887, Siiperintendeat of United Verde Copper Company,
Arizona. 1888, spring, en geological work for the Southern Pacific Compaay in West
Texas. Summer and fall, running gold mine and mill for self in Arizona. 1889-90,
Manager for U. S. Circuit Court in suit between the Con. Kansas City Smelting and
Refining Company and tiie Guadalupe C<»m,pany, in Nuevo Leon, Mexico. 1890 to
February, 1891, employed by<the CompauiaMetalargica Mexicana. March and April,
1891, charge of cojpper snicker, Tucson, Arizona. Expert work until 1892, when re-
turned to Com p. Metal., Mexico.
HoLDEN, Edward Henry, C. E., . . . . . 1878.
1074 Boston Avenue, New York City.
Hollerith, Herman, E.M., Ph.D. (1890), . . . 1879.
Electrician and Expert, 501 F. St., Washington, D. C.
HoLLicK, Arthur, Ph.B., 1879.
Columbia College, New York City and New Brighton, N. Y.
Superintendent Mexican Mine, Mariposa, <Da]., 1880. Kew York City Health De-
36 —
partiueut Inspector from 1881-90. Sanitary Engineer from 1890-91^ Special In-
spector, ]8J)2. Special Expert and Inspector of Offensive Trades, Xew York State
Board of Healtli, both in consultation and field work, from IS^^S to date. Boai'd of
Health, VilhiKe of New Brighton ; 1880-92, a menilier of the Board. Board of Health,
Long Island City, Sanitary Adviser, 1890. In general practice as a sanitarian from
1883 to date. U. S. Geological Survey — engaged in collecting specimens in the Terri-
tories, in 1882. Appoint*^d Fellow in Geology, Columbia College, January, 1690; re-
appointed, 1891 ; Assist., 1892. 1893, Tutor in Geology. Recording Sec'y Torrey Bo-
tanical Club, N. Y., 1883-88. Corresponding Secretary Natural Science Association of
Staten Island, 1881 to date. Associate Editor, BuUetin, Torrey Botanical Club, 1888-
I'^na
Mollis, Henry Leonard^ E.M., 18S5.
1232 Tlie Rookery, Cliicago, III., and 804 Perry-Paine Bldg., Cleve-
land, 0.
I^Sii, Assistant Chemist Edgar Thomson Steel Works. 1885-87, Assistant Chemist.
North Chicago Rolling Mill Company. 1887-90, Chief Chemist, North Chicago Roll-
ing >fill Company, which, in 1889, became by consolidation part of the Illinois Steel
Company. Ih90, member of firm of Rattle, Nye & Hollis, Analytical Chemists and
Mining Engineers. 1893, Member of firm of II. L. Hollis & Co., Analytical Chemists
and Mining Engineers.
Hollis, William, C.E., 1878.
Box K)9, Eagle Pass, Texas. Agent for Alamo and Coahuila Coal Cos.
Holt, Marmaduke BuRRELL, E.M., .... 1881*.
Colorado Smelting Company, Pueblo, Colo., and 287 Lexington Ave.,
New York City.
1889-90, Student in course of Electrical Engineering, School of Mines. 1890-91. with
Aspen Mining and Smelting Com pi^ny, serving as Mining and Electrical Engineer.
1891 to fall of 1892, Agent and Electrical Engineer with the " C. and C." Electric Motor
Co., N. Y. City and Denver. 1892-93, \ssayer Colorado Smelting Co., Pueblo, Colo.
H(K)KER, William Augustus, A.B., A.M., E.M., 1869.
Hooker & Lawrence, 145 Broadways New York City.
Hooper, Frank Cyrus, Met. Eng., .... 1890.
American Graphite Co., Ticondcroga, N. Y.
1890-1891, Asvsistant Engineer De Lamar Mining Co., Limited. 1892-93, American
Graphite Co. Spring, 1893, Investigation and report on Sisal Hemp Industry in The
Bahamas for The Inagua Fibre Co. Summer and Fall,. Erection of Concentrating
Hopke, Theodore M,, Ph.B., 1880.
Pitt.sburgh Reduction Co., Ferguson Building, Pittsburgh, Pa.
August, 18H9, November, 1881, Analytical Chemist with Ledoux & Co., New York.
November, 1881 to November, 1885, Member of the firm of Elliott, Hopke & Mattison,
Analytical and Consnlting Chemists and Assayers. July, 188G to November, 1889,
Cliemist for Linden Steel Co., of Pittsburgh, Pa , also had charge of Physical testing de-
partment. November 1889 to date. Manager Open-Hearth department of above Co.,
having full charge of manufacture of all gradis of sti-el made by the company, also
building of open hearth furnaces.
Horne, William Dodge, Ph.B., 1886.
Yonkers, N. Y.
June, 18h6 to December, 1887, Chemist to Fulton Sugar Refinery, Brooklyn, N. Y.
Octo]>er, 1887 to December, 1887, Assistant Instructor in Chemistry, School of Mines,
— 37 —
Columbia College. December 1887 to June, 1888, Chemist to St. Louis Snirar Refinery,
St. Louis, Mo. October, 1888 to October, 1889, Chemist to Standard Sugar Refinery,
Boston, Miiss. November, 188P, to present time. General Analytical Chemistry, Lab-
oratory and office in New Brunswick, N. J. January, 1890, to present time, Chemist
to Delaware Sugar House, Philadephia, Pa. January, 1891, to present time. Instruc-
tor in Analytical Chemistry in Rutgers College, New Brunswick, N. J. January 1890
to January 189.3, Consulting Chemist to Delaware Sugar House, Philadelphia. Janu-
ary to June, 1891, Instructor in Analytical Chemistry at Rutgers College, New Bruns-
wick, N. J. May, 1893, Consulting Chemist to National Sugar Refining Company,
Yonkers, N. Y.
Howe, Epenetus, E.M. (Life Member), .... 1886.
Box 69, Monterey, Mexico, and North Salem, N. Y.
Assayer and Chemist with the El Paso Smelting Co., and the Argentine Works,
Kansas, 1887-1889, and with Lacia Constancia Esmeralda Sierra Mojada Coahuila,
Meifico, 1889.
HoYT, Walter LowRiE, E.M., C.E., .... 18V6.
St. Louis Smelting and Refining Company, St. Louis, Mo.
1877-1880, Chemist and Metallurgist at Smelting Works in Utali, Montana and Col-
orado. 1880-1884, Metallurgist with Omaha & Grant Smelting and Refining Co.,
Omaha, Neb. 1884. Mining Engineer with El Callao Gold Mining Co., Venezuela, S.
A. 1885-1891, Superintendent St. Louis Smelting and Refining Co., St. Louis, Mo.
Humbert, William Scott, E.M. , 1883.
Niagara Falls, N. Y.
1883-1885, Surveys and location of Tunnel for New Croton Aqueduct. 1885-1887,
Construction work new Croton Aqueduct and extensive Topographical Survey of the
Croton Valley. 1887-1888, In charge of construction as Assistant Engineer at shafts
No. 21, No. 22, and No. 23 New Croton Aqueduct (night shift). 1888 to 1891 Assistant
Engineer in charge of the construction of two large dams and tunnels connecting the
two basins of Douhle Reservoir " I," located 2 miles east -of Brewster, N. Y., on the
east Branch of the Croton River. 1891, Special Assistant Engineer Cataract Con-
struction Company.
Hunt, Frederick Furneaux, E.M., C.E., . . . 1876.
77 Pine Street, New York Citj-. and New Brighton, S, L
Huntington, Fredkrick Wolcoti^, E.M., • • . 1885.
Hurlbut, Elisha Denison, Jr., C.E., , , , . 1890.
100 Hicks Street, Brooklyn, N. Y.
1890-91, at Columhia College Law School. 1891-93, Assistant in Mechanical Engi-
neering, School of Mines.
Hutto.v. Fredeuick Remsen, A.B., A.M., E.M., C.E.,
Ph.D. (Life Member), 1876.
Columbia College, and 200 Lexington Avenue, New York City.
1876-1877, Assistant in Engineering, School of Mines. 1H77-1882, Instructor in
Mechanical Engineering?. 1 882-1891. Adjunct Professor Mechanical Engineering.
1891, Professor Mechanical Eugineeriug.
Hyde, F. S., 1893.
215 Scbemierhorn Street, Brooklyn, N. Y.
Investigations in Glass, for L. C. Tiffany, New York City.
— 38 —
I.
Iiii^EXG, Axel Olaf, B.S., E.M., C.E., .... 1877.
Carthage, Mo.
1877-lvS32, Chief Chemist, Havemeyer J?iiRar Refininj? Co., RroakTyn, E. D. 1882-
1890, U. S. Dep. Mining Surveyor, District of a)loraflo. 188-2-1883, Chemist and
Assayer, La Plata Smelter, Leadville, Colo. 1883, >fetallirr^i8t, Martha Rose Smelter,
Silverton, Colo. 1884, Assayer, Sloiber S'amplin)7 Works, Silverton, Colo. 1885,
Duyckinck,*Schuyler & Ihlsen^, Ore Samplers, Silverton, Colo. 1886-1890. Manager
of Mt. Queen Mining Co , Reliance Mining Co., Brown Mining Co., and the Hale
Mines, Silverton, Colo. 1890-1892, Operating Zincite Mine and others near Webb
City, Nevada, and in constructing concentrating plants. Manager Pleasant Valley
Mines, Carthage, Mo.
Ihi^eng, Magnus C, KM., C.E., Ph.D., . . . 1875.
Professor Engineering, State School of Mines, Golden, Cola.
Iles, Malvern Welt^, Ph.B., Ph.D. (Life Member), . 1875.
Superintendent Globe Smelting Co., Denver, Colo.
Ingersoll, William Halsey, A.R, A.M., LL.B., E.M.,
(Life Member), ....... 1870.
North port, Suffolk County, N. Y.
1875-1878, Assistant in £Ingineering, Columbia Cbllege. lvS78-1831, Assistant in
Mechanics and Astronomy. 1881-1887, Manufacturing tin-\\'are, PortlaiKl, Conn.
1887-date, Incapacitated from practice by lack of l>ealth.
INGRAM, Edward Lanning, C.E., .... 1885.
Box 82, San Diego, Cal., and 109 Prospect Ave., BuffaJt^ N. Y.
From November, 1891, Principal Assistant E^igkieer, Intevnational Boundary Sur-
vey, United States and Meziuov
J.
Jackson, Oswald, C.E., 1892.
550 Park Ave., N. Y. City.
Inspector of Work on P. R. R., since January 1st, IS^l.
Jacobs, David Mark, Ph.B., 1887.
K J. Jacobs, 41 New St., and 30 W. Tliirty-eigbth St., N. Y. City.
Jacobs, Solomon Joseph, Ph.B., . . . . . 1887.
R. J. Jacobs, 41 New St., and 30 W. Thirty-eighth St., N. Y. City.
Janeavay, John Howell, E.M., 1886.
John A. Roebling^s Sons Co., and 124 West Srat43 St., Trenton, N. J.
1886, Underground and Surface Surveyor for Cooper, Hewitt & Co. 1837-1891
Draughtsman and Designer and Constructing Engineer of Wire Rope Tramways in
Montana, Oregon, Alaska, and CiilifcM*nia for the Trenton Iron Co., Trenton, N. J.
Jenks, Arthur Wilton, E.M.. 1886.
Superintendent Balbach Smelting and Refining Co., Newark, N. J.
Summer 1886, New Jersey on Geological Work. 1836-1887, In Oerro de Pasco,
Peru, S. A. Assayer and Ctiemist to the commission examining that silver mining
district. Spring, 1887, In New York, Chemist with Ledoux & Co. 1887-1888, In Au-
rora, 111., Assistant at tlie works of the Chicago and Aurora Smelting and Refining
Company. Summer and Fall 1888, In Dutch Guiana, S. A., Assayer and Assistant in
— 39 —
the examination of gold deposits. Fall 1888 to 1893, in Aurora, Ills., Assistant
Superintendent at the Aurora Works of the Chicago and Aurora Smelting and
Refining Co. 1893, Superintendent Kootenay Reduction Co. 1894, Superintendent
Balbach Smelting and Refining Co., Jersey City, N. J.
Jedp, Bernard John Theodore, C.E., . . 1887.
Assistant City Engineer, 119 Walcott St., Indianapolis, Ind.
Johnson, Arthur Gale, E.M., 1885.
Jensen, Utah.
Johnson, Elias Mattison, Ph,B., ..... 1878.
Isaac G. Johnson & Co., Spuyten Duyvil, N. Y.
Johnson, Gilbert Henry, Ph.D., 1878.
Isaac G. Johnson & Co., Spuyten Duyvil, N. Y.
Isaac G. Johnson & Co., Spuyten Duyvil, N. Y.
Jones, John Elmer, E.M., 1893.
As.sistant Superintendent Mill Creek Coal Co., New Boston, Pa., and
Hazleton, Pa.
Jones, William Denison, Ph.B., 1888.
Hecker, Jones, Jewell Milling Co., 206 Produce Exchange, N. Y. City,
and 62 Clark Street, Brooklyn, N. Y.
JoPLiNG, Reginald FuRNEss, E.M., .... 1889.
American Wire Co., 842 Wilson Avenue, Cleveland, Ohio.
November, 1889 to February, 1890, Chemist, Otis Steel Co., Ltd. February. 1890-92,
Assistant Manager American Wire Co. Vice-president of same, January, 1892.
JouET, Cavalier Hargrave, Ph.B., .... 1882.
104 John Street, New York City, aiid Roselle, N. J.
Analytical Cliemist with Ledoux & Bicketts, 1H82-1875. Analytical Chemist with
G. H. Nichols & Co., Acid Manufacturers at Laurel Hill, L. L, from 1885-1888. Work
comprising analyses of their various products and a partial supervision of their mana-
factare. Analytical Chemist from 1888 to present time with Bicketts & Banks.
Kelly, William, A.B., E.M., 1877.
Yulcan, Dickinson Co., Mich.
1877, '79, '80, Assistant Superintendent. Chemical Copper Co., Phoenixville, Pa. 1878,
Chemist, Himrod Furnace Co., Youngstown, Ohio. 1881-84, Superintendent, Kemble
Coal and Iron Co., Biddlesburg, Pa.; 1885, Superintendent, Glamorgan Iron Co.,
Lewistown, Pa.; 1880-89, Superintendent, Kemble Iron Co., Biddlesburg, Pa.; In
charge of Bhust-furnaccs, Coal Mines, Coke Ovens, Ore Mines, Quarries, Bailroads,
etc. 1889 to date. General Superintendent and Geu'l Manager Penn Iron Mining Co.
Vulcan, Mich.; In charge of Iron-ore Mines on the Menominee Ban ge, Lake Supe-
rior. Also, 1885-89, President Board of Examiners of Bituminous Mine Inspectors
of Pennsylvania.
Kemp, James FuRMAN, A. B., E.M., .... 1884.
Prof. Geology, Columbia College, School of Mines, and 303 W. 138th
St., New York City.
Several months with the Band Drill Co., 1883-1884. Private Assistant to Prof. J.
— 40 —
S. Newberry, 1884-8.">. Student of Oeolopy and Mineralogy at the Universities of
Leipzig and Munich, Germany, I880-86. Instructor in Geolojry at Cornell, 1886-88.
Assistant Professur of Geology and Mineralogy, lHHS-91, and SL»cretary of the Faculty.
1888-89. Have travelled in the West in 1889, and for two summers past have been
working on the Geology of the Lake Champlain region and Adirondacks. Am
especially engaged on Inorganic and Economic Geology. 1891, Adjunct Professor of
Geology, School of Mines, Columbia College. Professor, 1892.
KlNSEY, FkANK WrLMARTII, C.E., 1891.
Manager for 11. W. Ilildretli & Co., 2 Wall St., N. Y. City, and 10
South Street, Newark, N. J.
Assistant to Engineers' Rapid-Transit Commission, 1891-92. Engineer of Construc-
tion East. Providence Water Works, 1892. Designing Engineer with S. M. Gray,
1892-93. 1893, Manager for R. W. Hildreth & Co.
KissAM, Henky Snyder, Ph.B., ..... 1886.
Architect, Psi Upsilon Club, 33 W. Forty-second St., N. Y. City.
1888-89, Manager of Office of Pickles & Sutton, Architects, Tacoma, Washington.
1889-90, Practicing Architecture with P. W. Morris under firm name of Kissam <fc
Morris, Tacoma, Washington. 1890 -J)2, Practicing Architecture alone under* name
of Henry Snyder Kissam, Tacoma, Washington. 1892, Practicing Architecture with
Jno. G. Proctor, under firm name of Proctor & Kissam, Tacoma, Washington. Dur-
ing 1893, in New York City, as Student of Special Coustruction.
Klepetko, F., E.M., 1880.
Boston and Montana Consolidated Copper and Mining Company, Great
Falls, Montana.
Superintendent Smelting Department, Tamarack, Osceola Copper Mannfacturing
Company, Dollar Bay, Mich. At present Superintendent of Construction of the Great
Falls Smelter, for the Boston and Montana Consolidated Copper and Silver Mining
Koch, Edward Cabot, E.M., 1879.
Assistant General Manager, Elmore Gold Co., Limited, Rocky Bar,
Idaho, and 160 E. Fifty-sixth Street, New York City.
1880, 1881, 1SS2, Assayer and Chemist at Sineltei-s, Leadville, Colo. 1883-1893, Sur-
veyor and Assistant Superintendent. L. A. G. Mg. ("o., Colo. 1889 to date, Assistant
General Manager E. G. Co., Ltd., and V. G. Co., Ltd., Idaho.
KoEN, Joseph John, C.E., 1888.
Board of Health, 301 Mott Street, New York City, and Pearsalls, N. Y.
1889-90, Computer on New Croton Aqueduct. 1890-91, to date, Sanitary Engineer
on New York City Board of Uealth.
KuNHARDT, Wheatox Bradisht, EM. (Life Member), . 1880.
32 Beaver Street, New York City.
1880-82, Travel and Study in the West and in Europe. 188:J-88, Engineer for the
Bower-Barff Rustless Iron Co., and Assistant of Geo. W. Maynard in consulting work
on Iron-mines and Ore-dressing. 18SS-89, First Assistant Engineer of the Baston
Heating Co., under A. V. Ahbot, as Chief Engineer. 1890-91, Examination and
Exploration of Iron and Coal D^'posits in New England, with the Diamond Drill.
Report on Direct Steel Processes and on Magnetic Separation for Iron-ores. Acting
Secretary of the American Institute of Mining Engineers for four months. 1892,
President of tiio Oiceola (Gold) Gravel Mining Com pen y.
Kurtz, Edward Laurence, E.M., 18.93.
In Europe, 1894.
— 41 —
L.
LAaWuB, Charlks Frederick, E.M., .... 1885.
The Mountain Electric Co., P. 0. Box 1545, and 1 and 2 Duff Block,
1754 Larimer Street, and 1528 Gilpin Street, Denver, Colo. Also,
University Club, New York Cit.v.
1885 to 1880, Assayer and Surveyor and Foreman of Lucky Boy and South Galena
Mines, in Bingham, Utah. 1SS6 to 1888, Assistant Instructor in Assaying, and Fellow
in Chemistry, School of Mines, Columbia College, N. Y. 18^8 to 18iK), Examining
Gold and Silver Mines in Colorado, Utah, Montana, Arizona and Old Mexico. 1890,
Testing Electrical Apparatus in Virginia City, Nevada. 1890, Manager of the Gilpin
Co. Light, Heat and Power Co., Central City, Colo. 1890 to date, President and Man-
ager, The Mountain Electric Co. Specialty, Installing Electric Light and Power
Stations, and adapting electric light and power for mining purposes.
Lahey, Joseph, E.M., 1887.
162 E. Scyenty-eiglith Street, New York City.
Lahey, Richard, E.M., 1887.
Wilson Bros. &Co., Drcxel Building, Philadelphia, and 162 E. Sev-
enty-eighth Street, New York City.
Lamb, Andrew Johnson, E.M., 1884.
L. & N. Railway, Louisville, Ky.
June, 1884, to June, 1887, New York Croton Aqueduct, Draughtsman. June, 1887,
to Sept., 1890, Assistant Engineer, L. & N. Railroad. Sept., 1890, to June, 1891,
Langmuir, a. C, 1893^.
22 Leopoldstrasse, Heidelberg, Germany.
Langthorn, J. S. (Associate), 1891.
Superintendent's Office, Jamaica and Brooklyn Electric Road Company,
Jamaica, L. I., N. Y., and 196 Joralemon Street, Brooklyn, N. Y.
Lawrence, Benjamin Bowden, E.M., .... 1878.
Hooker & Lawrence, 810 Boston Ave., Denver, Colo.
1878-84, Superintendent, Montezuma S, M. Co., and of other mines of Summit Co.,
Colo. 1884-91, Lessee and Operator of Mayflower and Pelican-Dives Mines, Clear Creek
Co., Colo. In 1886, Formed partnership with W. A. Hooker, E.M., Class of 18(59, with
office at 145 Broadway, as Consulting Mining Engineers. I make a specialty of oper-
ating under lease or otherwise, true fissure Gold and Silver Mines, also Concentration
of Gold-silver ores. 1893-1894, Georgetown, Colo., at the Pelican-Dives Mines.
Leary, Daniel James, C.E., E.M., .... 1881.
Eagle and Provost Streets, Brooklyn, N. Y., 22 State Street and 43 E.
Twenty -fifth Street, New York City.
1882 to date, Constructing Highway and Railroad Bridges, Wharves, Docks, Dredg-
ing and Harbor Improvements generally, in vicinity of New York City, as Designing
and Supervising Engineer, as well as Contractor in most instances. In general,
make a specialty of both Engineering and Constructing work, or Engineering work
alone, in this branch of the profession.
Leary, George, C.E., 1891.
43 E. Twenty-fifth Street, New York City.
Leavens, Harry Wenman, E.M., .... 1875.
Salt Lake City, Utah.
— 42 —
LeBoutillier, Clement, Ph.B., 1881.
High Bridge, New Jersey.
1884-7, Assistant Chemist, Cambria Iron Co. 1887-92, Chemist, Eliza Furnace.
March, '92, to date. Chemist, Taylor Iron and Steel Company.
Lederle, Ernst Joseph, Ph.B., 1886.
Assistant Chemist, New York City Health Dept., 42 Bleecker St., and
120 W. 90th St., New York City.
1886-87, Hon. Fellow Quant. Anal, and Assist. Intr. Gen. Chemistry, School of
Mines. 1887-88, Chemist, Cranmoor Farm, Tom's River, N. J. 1888-89, Asst. Chem-
ist, New York City Health Dept. 1890-91, Chemist and Supt., Reed & Carnrick, New
York. 1891-92 as ahove, specialties, food and food preparations. Lecturer on Chem-
istry and Director of the Chemical Laboratory, New York Dental School.
Ledoux, Albert Reid, M.S., Ph.D. (Associate), . . 1874.
Ledoux & Co. , 9 Cliff Street, New York City.
Lee, George B A rstow, E.M., ...... 1886.
Brentwood, L. I., N. Y.
18(55, Assjiyer in Butte, Montana. 1886-1887, Assayer, Kansas City Smelting and
Refining Co. 1887 to date. Assistant Superintendent, Rio Grande Smelting Co.,
Socorro, New Mexico. 1890 to 1894, Superintendent, Rio Grande Smelting Works,
Socorro, New Mexico.
Leggktt, Thomas Haight, E.M., 1879.
Standard Consolidated Mining Co., Bodie, Mono County, Cal., also
1880, Assistant Engineer, New York River and Harbor Surveys. 1881-1883, Saperin>
tendent of Mining Properties in the Batopilas District, Chihuahua, Mexico. 1884,
Travelling in the West, through the principal Mining Camps. Butte, Leadville, etc.
1884-1887, Mining Engineer to the New York and Honduras Rosario Mining Co., at
San Juaucito, Honduras. 1888, Manager of Mudsill Mining Co., Fairplay, Colo.; of-
fice, 23 Bucklershury, London, E. C. 1889-1890, General Manager, Darien Gold
Mining Co., Ltd., of Cana, Rep. of Colombia. 1891-93, President and Manager Standard
Consolidated Mining Co.
Lenox, Lionel Remond, Ph.B., 1888.
Assistant Professor Chemistry, Leland Stanford, Jr., University, Palo
Alto, California.
After three years' work in the School of Miues, and previous to my senior year, I
was respectively in : 1887, three mouths Assistant Chemist to Fulton Sugar Refinery.
1887, six montlis Assistant Chemist to Bethlehem Iron Co. 1888-89, Instructor in
Qualitative Analysis and Assaying, Lehigh University. 1889-91, Instructor in Quan-
titative Analysis and Industrial Chemistry, Lehigh University. 1892-93, Chemist,
Bureau of Ordnance, Washington, D. C.
Levy, Albert Lrxa^LN, E.M., 1890.
Fischel & Levy, Hartford, Conn.
LiEBMANN, Alfred, C.E., 1893.
28 East Seventy-second Street, New York City.
Lilliendahl, Alfred Whipple, E.M., .... 1883.
Superintendent, Mazapil Copper Co. (Ltd.), Concepcion del Oro, Es-
1883-85, Assistant Supt. Aurora Smelting and Refining Co., Aurora, 111. 1885-87
— 43 —
Assistant Sapt. Grande Milling and Refining Co., Guani^aato, Mexico. 1886-93^ Sa-
periutendent of the Mazapil Copper Co., Ltd., Conccpciou delOro, Zacateeas, Mexico.
LiLLiENDAHL, Frank Armstrong, E.M., . . 1891.
Assistant Superintendent and Metallurgist, Mazapil Copper Co. (Ltd.),
Concepcion del Oro, Estado de Zacateeas, Mexico, (via Laredo, via
Saltillo).
1891-93, as above.
LiLiENTHAL, JoHN Leo, E,M. (Life Member), . . 1870.
1918 Jackson Street, San Francisco, Cal.
1871, Assistant in Laboratory, Prof, Chandler, School of Mines. Assistant in Field
Work, Prof. Newberry, Ohio (Geological Survey. Assistant in Lecture Room, Prof.
Joy, Colambia College. Assistant in Metallurgical Laboratory, Prof. Egleston,
School of Mines. 1872-1891, Mercantile Business, San Francisco.
LiLLiE, Samuel Morris, E.M., 1874.
1874-75, Chemist, Kings County Refining Co., Green Point, L. I. 1876-8.5, Chemist,
Franklin Sugar Refinery, Philadelphi(\, Pa. 1886-1887, Sugar Engineer and Chemist.
1888, 1889 and 1890, Vice-President and Manager of "The Sugar Apparatus Manufac-
turing Co.," a Company organized under the Laws of Pennsylvania, to operate under
his patents. 1891, President of said Company.
Lipps, Henry, Jr., C.E., 1888.
R. & D. R.R., Box 14, Greensboro, N. C.
From July, 1888, to August, 1889, Assistant Engineer Maint. of Way, Dep. R. & D.
R.R., W. N. C. & Va. Mid. Div. August, 1889, to January, 1890, Supervisor Track,
N. C. Div. R. & D. R.R. January, 1890, to date. Engineer Maint. of Way, N. C.
Div. R. & D. R.R.
Little, Willard Parker, E.M., Ph.B 1881.
Architect, 28 West Twenty-Third Street, New York City.
Livingston, Archibald Rogers, C.E., .... 1891.
20 North Washington Square, New York City.
Since November, 1891. in employ of Lackawanna I. & S. Co., Scran ton. Pa.
IjOngacre, Lindsay B., M.E., 1892.
Spuyten Duyvil, N. Y.
Lord, Frederick Reuben, C.E., 1892.
General Manager, Clifton Coal Company, Bay Street cor. Vanderbilt
Ave., Clifton, and Box 228 Stapleton, Richmond County, N. Y.
Love, Edward Gurley, A.M., Ph.B., Ph.D., . . 1876.
Gas Examiner, Department Public Works, and 80 E. 55th St., New
York City.
Ludlow, Edwin, E.M , 1879.
Superintendent Choctaw Coal and Railway Company, Hartshorn, Indian
Territory.
1879-81, Assistant Engineer in charge of hydrographic work on Delaware River,
under U. S. Engineer. 18S1, Assistant Engineer Mexican National Railroad, Mexico.
1882-89, Assistant Superintendent, then Superintendent, for Pennsylvania Railroad
coal-mines at Shaniokin, Fa. 1889 to date, Superintendent of Mines, Choctaw Coal
and Railroad Company, Hartshorn, Indian Territory.
— 44 —
LuQiiER, Lea McIlvaine, C.E., 1887.
Tutor in Mineralogy, School of Mines, N. Y. City, and Bedford, N. Y.
Summer of 1887, Assistant in Geodetic Surveying with Professor Rees. Summer
of 18S7, Assistant in Surveying with Professor Monroe. Summer of 188S, Assistant
in Geodetic Surveying with Professor Rees. 1887-90, Fellow in Mineralogy, School
of Mines. 1890. Assistant in Mineralogy, School of Mines. 1891 to date, Tutor in
Mineralogy, School of Mines.
LuQUER, Thatciiku Taylcr Payne, C.E., E.E. (1892), . 1889.
25f) Broadway, N. Y. City, and 618 Henry St., Brooklyn, N. Y.
1890, Fellow in Engineering. 1890-91, Fellow in Surveying and Practical Mining.
1891, Assistant in Mining, Columbia College, School of Mines. 1892, with H. Ward
Leonard & Co., New York City. 1893, Engineer, Union Electric Co., N. Y. City.
1894, Engineer the Fiter Conduit Company.
LusK, Graham, Ph.B, Ph D. (Munich, 1891), . . 1887.
Assistant Professor of Physiology at the Yale Medical School, New
Haven, Conn. Address: 47 East Thirty-f«mrth Street, N. Y.
1887-1888, Student at Munich. 1889, Student at Munich ; also at Bellevue Hos-
pital Medical Cxtllcge, N. Y. 1890, Studied at Bellevue; afterwards in Munich.
1891, Studied at Munich ; and was later appointed Instructor of Physiology at the
Yale Medical School. 1892, Assistant Professor of Physiology.
Ltjttgen, Eberhard, Ph.B., . . . . ^ . 1884.
Wissahickon Chemical Works, Ambler and Chclten Hills, Wyncote
P.O., Pa.
1884-85, Assistant Chemist, Crane Iron Company, Catassiuqna, Pa. 1885 to date,
Chemist and Manager, Keasbey & Mattison's Cliemical Works, Ambler, Pa. Specialty,
manufacture of magnesia.
Lyman, Frank, A.B.,M.E 1878.
50 Remsen St, Brooklyn, N. Y.
M.
McCuLLOH, Edwin Au.stin, Ph.B., .... 1878.
Glencoe, Md.
McIlhiney, p. C, 1892.
619 Grand Street, Jersey City, N. J.
McKenna, Charles Francis, Ph.B., .... 1883.
221 Pearl Street and 144 West Ninety-ninth Street, New York City.
1R83 84, Chemist Havemeyer Sugar Refining Company, Jersey City, N. J. 188.5-86,
Chemist Canibr«a Company, Jcihnstown, Pa. 1887-90, Chemist Edgewater Lime
Works, Edgewater, N. J. 1890, Chemist Jas. J. McKenna & Bros., Brass Founders,
424, 426 Eiist Twenty-third Street, New York City. 1893, Director, Physical Testing
Department, Lahoratories, Dr. G. E. Moore, 221 Pearl Street, New York City.
McKiM, RoBEKT Albert, C.E., 1884.
Room 213, 280 Broadway, and 9 East Tenth St., New York City.
Assistant Engineer on New Croton Aqueduct. (Entered Aqueduct Engineer Corpa
as Chainman, in February, 1885.)
McLaughlin, Charles Swain, Ph.B., .... 1884.
874 Broadway and 2041 Fifth Avenue, New York City.
— 45 —
Ma cKa YE, Harold Steele, C.E., 1887.
Westinghousc Electric Mfg. Co., and 3407 Forbes St., Pittsburgh, Pa.
Three months' work in New York Harbor in Army Corps of Engineers. One year's
employment in the Office of Patent Solicitors. 1889-92, acting as Fourth Assistant
Examinef of the U. S. Patent Office. Since July, 189*2, Patent Counsel for Westing-
house Electric and Manufacturing Company.
MacTeague, John Joseph. E.M., 1883.
Mexican Ore Company, El Paso, Texas.
Maclay, James, C.E., 1888.
Tutor in Mathematics, Columbia College, and 87 Union Street, New-
ark, N. J.
Mahony, Arthur Stuart, E.M., 1889.
51 West Ninety- fourth Street, New York City.
1890, First Assistant Geneml Manager of the New Birmingham Iron and Land
Company. 1891, Treasurer of the same company, also Chemist to the Tassie Belle
Furnace, New Birmingham, Texas.
. Mannheim, Hermann Charles, E.M., .... 1887.
254 Cumberland St., Brooklyn, N. Y.
Mannheim, Paul August Louis, E.M.,. . . . 1885.
United Smelting and Refining Company, East Helena, Montana.
Marij6, Leon, E.M., 1885.
12 East Forty-sixth Street, New York City.
Marsh, John Rollin, E.M., 1887.
Chief Engineer Indiana Bridge Co., and 616 E. Adams St., Muncie, Ind.
August 1, 1887, to date, as above.
Martin, Edward Ward (Associate), .... 1877.
Chemist, Board of Health, 301 Mott Street, New York Cit3\
Massa, Charles Griswold, C.E., 1889.
143 W. 34th St., N. Y. City, and Fort Lee, N. J.
Oct. 1889 to date, on railroad and street railway construction, and miscellaneous
work.
Mass A, Louis Ferdinand, C.E., 1890.
Fort Lee, N. J.
October, 1890, to 1892, shop practice, Maryland Steel Works, at Sparrow's Point, Md.,
as follows: October, 1890, to July, 1891, Machine-shop practice. July, 1891, to Sept.,
1891, Bessemer-mill Construction. Sept.. 1891, to Sept., 1892, Bessemer Rail-mill and
Roll-house ; Mechanical and Metallurgical Engineering. October, 1892, to 1893, Post-
graduate Electrical Engineer at C/lumbia College.
Mathis, Theophilus Smith, E.M., .... 1879.
Engineer of Mines, and U. S, Surve3'or General's Office, and 529 East
St., Salt Lake City, Utah.
From January, 1890, to February, 1891. Assistant Draughtsman U. S. Surveyor Gen-
eraPs Office, Salt Lake City, Utah. Since Feb., 1891, Chief Draughtsman of Mineral
Division of said Office, and still holds that position.
Mayer, Ralph Edward, C.E., 1879.
Instructor in Mechanical Drawing, School of Mines, Columbia College,
New York City.
— 46 —
Meissxer, Caul August, Ph.B., 1880.
Vanderbilt Steel and Iron Company, Box 867, and 2512 7th Ave., Bir-
mingham, Ala.
One year. Assistant Chemist Joliet Steel Company. Three y<»ars, Chemist and
Assistjint Snperintendeut Brier Hill Iron and Coal Company, Youngstown. Ohio.
One and a half years. Head Chemist Joliet Steel Company. Three years, Manager
Sterling Iron and R'wy Company, Sterlington, N. Y. At present, Vice President
and General Manager of the Vanderhilt Steel and Iron Company, Birmingham, Ala.,
after having personally organised this company. President, Jefferson County Min-
ing and Quarrying Company.
Melliss, D. Ernest, A.M., Ph.D. (Associate),. . . 1868.
Price's Building, 524 Sacramento Street, San Francisco, Cal.
^tudent regular course, three years, School of Mines. Afterwards, two and a half
yeara University of Goettingen, graduating Ph.D., in 18G9. One year at University
of Vienna. Since then, constantly occupied in civil and mining engineering. In
1873, was Chief Engineer in charge of Topographical and Geological Survey of Guano-
caste and Nicoya for the Costa Bican Gt)vernment. In 1881, Consulting Engineer to
the Pacific Gas Light Company, of San Francisco, and in its interest studied the dif-
ferent gas-making systems in the United States, England, France and Belgium.
Have made plans for and erected numerous gold, silver, copper and lead mines.
Planned the Union Iron Works of San Francisco, and superintended their construc-
tion ; also the Arctic Oil Works and several other industrial establishments on the
Pacific Coast. Designed and built the MazatUn Water Works in Mexico ; the Hy-
draulic Press Brick Works, of California, the largest establishment of its class on the
Pacific Coast. Four years in Central America and Mexico. Was Administrator of
San Josii de las Bocas and Consulting Engineer to Guadalupe de los Reyes, the most
successful silver mine of Sinaloa. Now Consulting Engineer in San Francisco, and
particularly occupied in that capacity for the Olympic Salt Water Company, whose
works are now being erected under his supervision and according to his plans.
Merrill, Frederick James Hamilton, Ph.B., Ph.D., . 1885.
State Museum, and 2 Sprague Place, Albany, N. Y.
1885-87, Assistant on the Geological Survey of New Jersey. 188d-90, Fellow in
Geology, Columbia College. 1890 to date. Assistant State Geologist and Assistant
Director of the New York SUite Museum, Albany, N. Y.
MERRirr, James Haviland, Ph.D., A.M., . . . 1880.
Care of Trenville Temple Smelting Company, 41 E. 49th St., New
York City, and 3 Munroe Place, Brooklyn, N. Y.
From 1881-1888, Chemist to the Bradley White Lead Co. In 18S9, entered the
School of Mines as Post Graduate in the course of Architecture. 1892-i>3, Architec-
tural Study.
Merwin, Hubert John, E.M., 1879.
The American Association (Ltd.), Middlesborough, K}\
Merz, Eugene, M.E., 1892.
Box 112, and 143 Littleton Ave., Newark, N. J.
MfiSEROLE, Walter Monfort, C.E., . • . 1881.
189 Montague St., and 2789 Atlantic Avenue, Brooklyn, N. Y.
1881, Transitman and Topographer Continental Railway Co. 1881-83, Assist. Eng.
in Construction N. Y., West Shore and Buffalo Ry. 1884-85. Division Engin'r Mainten-
ance of Way ; IS&S, Chief Engineer Catskill Mtn. and Cairo Railway. 1885, in charge
Topographical Survey for Kings County Charities' Commission. 188G to date, in
— 47 —
General Practice, located at Brooklyn, N. Y. Specialties: Improvement and Devel-
opment of Real Estate and SiirveyinR for Legal and Construction Purposes; City
Surveyor of the City of Brooklyn ; Chief Engineer South Brooklyn R. R. and Ter-
minal Company, German- American Improvement Co., and Hancock and State Line
Railway Company.
Meyer, Herman Henry Bernard, E.M., . . 1885.
539 W. Twentieth Street, New York City, and 162 Heywood Street,
Brooklyn, N. Y.
Surveying, Field and Office work at Pelham Park, Westchester Co., July to No-
vember, 1885. December, 1835 to date, Engineer for Oregon Iron Works, New York ;
designing and erecting machinery for mauutacturing illumiuating gas.
Middleton, John, C.E., 1887.
2789 Atlantic Avenue, and 14 Glena'le Place, Brooklyn, N. Y.
1888 to date. Surveyor, Assistant to M. M. Meserole, C.E.
Miller, Charles Lewis, E.M., 1885.
Illinois Steel Company, 3179 Ashland Avenue, and 3009 Kllis Avenue,
Chicago, III.
1886, Assistant Chemist Edgar Thomson Steel Works, Braddock, Pa. 1886-87,
Chemist and Assistant Supt. Carbon Iron and Pipe Co., Parry ville, Pa. 1887-90, Supt.
The Missouri Furnace Co., St. Louis, Mo. 1890 to date, Supt. Blast Furnaces at Union
Works of Illinois Steel Co., Chicago, 111.
Miller, Charles Watts, E.M 1884.
Box, 401, Aspen, Colo.
1884-1885, Metallurgical Engineer Hecla Bronze and Iron Works. 1885-1886, As-
sayer and Chemist, Aspen, Colo. 1886-1891, Mining Engineer and United State
Deputy Mineral Surveyor, Aspen, Colo. General mining engineering business.
Miller, Edmund Howd, Ph.B., A.M. (1892),. . • 1891.
A8.sistant in Assaying, Columbia College School of Mines, and West
Nyack, N. Y.
1892-93, as above.
Miller, Rudolph Philip, C.E., 1888.
806 E. Leigh St., Richmond, Va.
1888-18C0, Assistant to E. M. W., 1890 to date. Supervisor R. and D. Railway.
MiLLiKEN, George Fanshawe, E.M., .... 1879.
Land Department, N. P. R. R., Tacoma, Wash., and Union League
Club. New York City.
1879-1880, Superintendent " Milton Mining: Company." 1880-iaS3, General Mana-
ger *' Chester Mining Company." 1883-1887, In General Consulting Practice as En-
gineer. 1887-1890, General Manager " Costa Rica Mining Co., Ltd." 1890 to date,
Moldehnke, Richard George Gottlob, E.M., Ph.D., . 1885.
McConway & Torley Co., Forty-eightli Street and A. V. R.R., and
104 Home Street, Pittsburgh, Pa.
1885, '8(>, '87, Three Summer seasons with United States Coast and Geodetic Sur-
vey, New York and Pliiladelphia Harbors and Cape Cod, Mass., Ifydrographic IVbrfc,
Triangulation, Levelling, etc. 188r>-188(), Winter, nine months. Sanitary Engineering^
Inspector, etc., New York Association for Improvement of Condition of Poor. 1887
-1889, Electrical Engineering, five months Mining Engineer Spraguc Electric Railway
and Motor Co., seven months Mechanical Engineer Crocker-Wheeler Motor Co., five
— 48 —
months experimenting on patents taken ont. 1889, Manufacturing for myself. Spe-
cialty in Machinists' Tools. 1889-18JK), Professor Mechanical and Electrical Engineer-
ing, Michigan Mining School, Houghton, Mich. 1890 to date, Engineer McConway &
Torley Co. (Manufacturers Jjinney Coupler, M. C. B. type). In addition to regular
Engineering Work of Manufacturing Plant, conducting Metallurgical Investigations
in line of Malleablization of Cast-iron. Specialties: Malleablized Cast-iron and Oil
Fuel Gas.
MoNELL, Joseph Thompson, C.E., . . . . . 1889.
Coliiiiibia College, and 236 W. Twenty-secoTid Street, New York City.
1891, Electrical Engineering, Curtis Electrical Mfg. Co. 1892 to date. Tutor in As-
tronomy, Columbia College.
Montenegro, Manuel Rafael, E.M , . . . . 1890.
539. W. 20th Street, New York City, and 53 Washington Street, IIo-
boken, N. J.
1890, Spiral Weld Tube Company, East Orange, N. J., and studying machine-shop
practice. 1891-189*2, engaged in the formation of mining companies. 1892 to date,
Assistant Superintendent Oregon Iron Works, New York Citj'.
Mora, Mariano Lui.«<, C.E., 1891.
Columbia College, School of Mines, New York City.
MoRAN, Daniel Edward, C.E., 1884.
Sooypuiith & Co.. 2 Nassau Street, and 26 W. Eighteenth Street, New
York City.
Morgan, William Fellowes, A.B., E.M. (Life Member), 1884.
Brooklyn Bridge Freezing and Storage Co. , Arch 4 Brooklyn Bridge,
New York City, and Short Hills, N. J.
1884-1888, Banking and Brokerage. 1888 to date, as above.
MORRLS, GOUVEUNEUR WiLLIAM, E.M., .... 1878.
Meyers, Rutherford & Co., 58 Wall Street, and 123 W. Thirty fourth
Street, New York City.
Banker and Broker.
MosLEY, Richard Keeler, Ph.B., .... 1889.
Architect, 19 W. Twenty-fourth St,, N. Y. City, and 139 Glenwood
Avenue, East Orange, N. J.
From June, 1889, to January, 1893, worked a.s Draughtsman in the Offices of S. J.
O'Conner, Carrere & Hastings, and Richard M. Hunt, of New York, and Benj. Silli-
man, of Yonkers, N. Y. Since January, 1893, practicing Architecture independently
Mose8, Alfred Joseph, E.M., Ph.D., .... 1882.
Adj. Professor Mineralogy, Cohiiiibia College School of Mines, and
9 Hudson Place, Now York City.
1882-1885, Assistant in Mineralogy, School of Mines. 1885-18J)0, Instructor in
Mineralogy and Metallurgy. 1890 to date, Adjunct Professor of Mineralogy. Man-
aging Editor School of Mines Quarterly.
MULFOKD, ROBEUT, E.M., 1884.
■\It. Vernon, N. Y.
1890, Assistant Superintendent Rio del Oro Gold Co., Argentine Republic, S. A.
1891, Honduras ?
— 49 —
MtJLLER, George, Ph.B., 1887!
Cheniint, care Puget Sound Reduction Co., Everett, Washington.
MuNOZ DEL Monte, Adolpho Carlos, C.E., Ph.B., . 1888.
Retarned from Enrope, November, 1892, where, from June, 1691, travelled as a
** McEim Fellow iu Architecture."
MuNROE, Henry Smith, E.M., Ph.D., .... 1869.
Professor Mining, Columbia College School of Mines, and 45 Sidney
Place, Brooklyn, N. Y.
1869-1870, Post Gniduate student in Chemistry and Economic Geoloj^y, School of
Mines. 1870-1871, ARsistant Geologist Ohio State Geological Survey. 1870-1872, As-
sistant Chemist, Department of Agriculture, Washington, D. C. 1872-1875, Assist-
ant Geologist and Mining Engineer, Geological Survey of Yeddo, Japan. 1875-1876,
Professor of Geology and Mining, University of Tokio, Japan. 1877-1891, Adjunct
Professor of Surveying and Practical Mining, and 1891, Professorof Mining, School of
Mines Columhia College, New York City. Specialties, Economic Geology, Ore Dress-
ing, and Mining Engineering. 1881-1884, Manager, and 1890-1892, Vic^-Presideut
American Institute Electric Engineers.
Munroe, Otis Mortimer, Ph.B., 1879.
Banker, De Soto, Mo.
MuNSELL, Charles Edward, Ph.B., Ph.D., . . . 1878.
Assistant Chemist, F. W. Devoe & C. T. Reynolds Co., 283 Plymouth
Street, New York City, and Rye, N. Y.
November, 1878, with A. E. Foote, Mineral Dealer, Philadelphia. March, 1879,
with T. a. Edison, Menlo Park, N. J. May, 1879, Chemist, Bnshwick Chemical
Works, Brooklyn, N. Y. October, 1879, Stencilographer and Celestyper, School of
Mines, N. Y. January, 1880 to December, 1885, Milk Inspector, New York City
Health Department. July, 1881 to May, 1883, State Milk Inspector, New York State
Board of Health. January, 1886 to date, Analyst and Assistant Chemist, F. W. Devoe
& Co., and C. T. Reynolds Co., New York City. Specialty, Paints and Colors.
Murphy, Henry Morgan, E.M., 1878.
Murphy Varnish Co., Chestnut and McWhorter Streets, Newark, N, J.
Murphy, John Glenville, E.M., C.E., .... 1877.
Times Building, New York City.
Assistant Superintendent Orinoco Exploring and Mining Co., Gold Mine. Assist-
ant Superintendent Callao Gold Mining Co. Territorial Geologist of Wyoming. Su-
perintendent Esmeralda Mining Co., Black Hills, Dakota, Gold Mine. Superintend-
ent New York and Lee Mountain Syndicate, Montana, Lead-Silver Mines. Has
made professional examinations in nearly all parts of the United States, the Pachuca
Silver and Jugnann Copper Districts in Mexico, and two and half years ago made a
six months' trip in Colombia and Ecuador.
N.
Napier, Arthur Howell, E.M., 1884.
Sanitary Engineer, Lincoln Bldg., 1 Union Square, West, New York
City, and 179 Harrison Street, Brooklyn, N. Y.
1884, Sanitary Engineer and Inspector for New York State ''Tenement House Com-
mission "and New York " Society for Improving (condition of Poor." 1885-1889-
*' Assistant Sanitary Engineer," New York Health Depiirtment. 1889 to date. Prac-
ticing as Sanitary Engineer, New York City.
4
— 50 —
Hacienda de San Cristobel Aciimbara, Estado de Guanajuato, Mexico,
and care Mexican Consul General, 35 Broadway, New York City.
1881-1882, Civil Engiueering Course in Polytechnicum, Hanover, Germany. 1882-
1884, Mexican Government Commissioner to study railway systems of Europe. 1885
1887 to date, Engineer in charge of Surveys and Representative in Chiopasofthe
Mexican Land and Colonization Co.
Neftkl, Kmgut, C.E., Ph.D 1879.
Nesmith, Jame8^ E.M., ....... 1879.
256 Henry Street, Brooklyn, N. Y.
Newberry, Spencer Baird, E.M., Ph.D., . . 1878.
Professor Cliemistry Cornell University, Ithaca, N. Y.
Newberry, Woi.a>TT Ely, E.M., 1884.
1885-1885, Metallurgist, Casa Grande Co., Arizona. 1885-1886, Assistant Superin-
tendent Cananea Mg. Co., Sonura, Mexico. 1886-1887, Superintendent Argentum
Mining Co., Aspen, Colo. 1887, General Manager Aspen Mg. and Smelting Co., As-
pen, Colo. 1888 to present time, General Manager Enterprise Mg, Co., Aspen, Colo-
Superintendent Aspen Contract Mg. Co., Aspen, Colo. Superintendent Mutual Benefit
Mining and Milling Co., Aspen, Colo. 1892, General Manager Isabella Gold Mining
Company, Cripple Creek, Colorado. 1893, as above.
Newbrough, William, A.B., E.M., .... 1884.
128 W. Thirty-fourth Street. New York City.
Newhouse, Edgar LiEBER, E.M., 1886.
75 and 77 Worth Street, New York City.
NiCHoii^, Ralph, HM., C.E., 1877.
General Superintendent, The Comstock Tunnel Co., Sutro, Lynn Co.,
Noble, Louis Spencer, E.M., 1885.
76 W. Ninetieth Street, New York City, and liCadville, Col.
1885-1889, Mining Engineer to Iron-Silver Mg. Co., and Nisi Prius Cons. Mg. Co..
of Leadville, Colo. Also during 1889 Consulting, Reporting and Law-suit work on
otiier Colorado properties. 1889-1890, Superintendent of Mines and Mining En-
gineer to Constancia Mining and Smelting Co., at Sierra Mojada, Coahuila. Mexico.
1890-1891, Mining Engineer on Law-suit preparation, with Blue Bird Mining Co.,
Ltd., of Butte, Montana. Specialty, Lead, Silver and Gold Mines and Mining.
Nolan, Thomas, M.S., Ph.B., 1884.
Architect, 503 Wilder Building, Rochester, New York.
NoRRis, Dudley Hiram, E.M., 1877.
NoRRis, Robert Van Ar-dale, E.M., .... 1885.
Assistant Engineer, P. R. B., Dept. of Anthracite Coal, Room 28, First
National Bank Building, and 24 S. Franklin Street, Wilkesbarre, Pa.
1885, Assistant in Practical Mining and Surveying, School of Mines. U. S. Inspector
— 51 —
of Dredging, in charge of Manrice River Improvement, MillviDe, N. J. 1886, Chem>
ist, Herman Behr. Manufacturer of Colors, Brooklyn, N. Y. June, 1886, to date, Assist-
ant Engineer, Pennsylvania Railroad, Department of Anthracite Coal Collieries. Spe-
cialty, Mechanical Engineering of Collieries.
Norton, LuoiEN HoLLEY, E.M., 188(5.
Mingo Smelting Co., Sandy, Utah, and 123 Fairfield Avenue, Bridge-
port, Conn.
1837-1890, Engineering OiBce, N. Y., N. H. & W. R. R. Experience in Railroad
Construction, Location and Preliminary Surveys, Office Work and General Survey-
ing. 1890, Assayer and Engineer to West Indian New Gold Mining Corporation, San
Domingo, West Indies. Experience in Free Melting of Gold-ores, Assaying, Survey-
ing, etc. January, 1891-92, Assayer for Daly Mining Co., Park City, Utah. Ex-
perience in Assaying, General Analyses. Also Leaching of Silver-ores by the
Russell Process. 1892 to date, as above.
NoYEs, James Atkins, Ph.B., A. B. (Harvard, '83), (Life
Member), 1878.
74 Sparks St. , Cambridge, Mass.
NoYES, WiLLFAM Skaats, E.M., 1875
Shafter, Presidio County, Texas, and Oakland, Cal.
1877-1879, Assayer for McCrackin Mining Co., Mohave Co., Arizona. 1879-1881,
Foreman of Bodie Mill, for Bodie Coal Mining Co., Bodie, Cal. 1881-1883, Examining
Mines for San Francisco Capitalists. 1883 to present time, Superintendent of Pre-
sidio Mining Co., and The Cibilo Creek Mill and Mining Co., Shafter, Presidio Co.,
Texas.
Nye, Alvan Crocker, Ph.B , 1884.
Hayden Furn. Co., 1 West Thirty-fourth St., and 107 E. Seventieth
Street, New York City.
1884-a5, Draughtsman, C. C. Haight, Architect, New York City. 1885-90, -Designer
and Head Draughtsman, Herter Brothers, New York City. 1890 to date, Furniture
Designer and Architect, The TiflHuy Glass Co., New York City. 1892, Chief Designer
as above.
o.
O'Connor, Michael Joseph, E.M., Ph.B., . . 1881.
Architect (1884), 28 W. Twenty-third Street, New York City.
O'Connor, Thomas Devlin, Ph.B., .... 1881.
O'Connor & Elliott, 16 Exchange Place, and 12 E. Forty-fourth Street,
New York City.
Olcott, Eben Erskine, E.M., 1874.
Mining and Metallurgical Engineer, 18 Broadway, and 38 W. Thirty-
ninth Street, New York City.
1874-75, Chemist to the Ore-Knob Copper Co , in charge of Hunt &, Douglass Pro-
cess. 1875-76, Assistant Snpt Penna. Lead Co.'s Works, Mansfield Valley, Pai. 1876-78,
Assistant Supt. Orinoco Exploring aud Mining Co., at their Gold Mines in Venezuela.
1878-70, Supt. of the same. 1879-81, Examining Mines in Colorado, Utah, Nevada
and California, for New York Investors. 1881-85, Supt. St. Helena Gold Mines, So-
nora, Mexico. 188o, opened office in New York as Consulting Engineer, and since
then has been engaged as Consulting Mining and Metallurgical Engineer, in Peru,
Republic of Colombia, Dutch and British Guiana, Mexico, British Columbia, Ontario,
New Brunswick, and the United States.
— 52 —
Ormsbee, James Jackson, E.M., . . . . . 1886.
The Sequacliee Valley Coal and Coke Co., Pikeville, Bledsoe County
Tennessee.
1886-91, Miuing Engineer at Tracy City Mines, of Tennessee, Coal, Iron and Kail-
road Co. 1891 to date, Superintendent, Thomas Coal Mines, of Tennessee Coal, Iron
Osterheld, Theodore W., E.M., . . . . 1886.
Yonkers, N. Y.
Assistant Superintendent of Blast-furnaces, P. S. Co., 1886-87. General Foundry
Practice, Worthington P. Works, 1887-88. Owner of Foundry and General Iron
Works, 1888-89. Vice-President, Pendleton Mining Co., and Consulting Engineer,
1889, '90, '91, and General Consulting Engineer, Iron and Coal Specialty, and Metal-
lurgist of Iron and Finished Manufacturing. Interval of 1880-91, of the months
December to May, Superintending Construction of Rolling Mill, Southwest Virginia.
Specialty, Coal and Iron of the Virginias. President of the Southern Reducing Co.,
Experts, Chemists and Mining Engineers.
Owen, Frederick Nash, E.M., 1878.
Civil and Sanitary Engineer, 58 W. Ninety -first Street, New York Citj'.
P.
Page, George Stephen, fl.M., 1885.
Care of Park Bros. & Co., Limited, Pittsburgh, Pa.
Manager of Steel Works.
Page, William Stevens, E.M., 1882.
Aqueduct Commission^ Sing Sing, N. Y.
Painter, Charles Albert, E.M., .... 1884.
Ji Painter & Sons, Pittsburgh, Pa.
Painter, George Edwards, Ph.B., .... 1883.
J. Painter & Sons Co., Pittsburgh, Pa., and 20 Bedwin St., Allegheny
City, Pa.
Parker, Andrew McClean, E.M., .... 1880.
Acting 1st Assistant Engineer, Dept. of Docks, Pier A, and »% W. One
Hundred and Nineteenth Street, New York City.
Parker, Herschel Clifford, Ph.B., . . . . 1890.
Dei:>t. of Physics, Cokimbia College, New York City, and 21 Ft.
Greene Place, Brooklyn, N. Y.
1890-91, Fellow in Physics^ Assistaat Instructor, Course in Physical Measure-
meuts. 1891-d3, Assistant. 189a-{M, Tutor in Physics.
Parker, Richard Alexander, C.E., .... 1878.
East Ohio Street, Marquette, Mich.
1878-79, Assistant Superintendent, Montezuma Silver Mining C6., Montezuma*
Colo. 1830-81, Surveyor at Georgetown. 1831-82, Chief Draughtsman, Mexican
Natl. Cons. Co., Laredo, Texas. 1883-84. Examining Mines in Colorado. Utah and
Idaho mainly 1885-86, Superintendent, Atlanta Hill Gold Co. Also Superintendent
of the Big Lode (Gold) Co., Atlanta, Alturas Co., Idaho. 1887 to date. Resident Mana-
ger and Asrent for Samson Iron Co., Imperial Iron Co.. and Barasa Iron Co. Also Con-
sulting Mining Engineer. Specialties, Gold and Silver Mining and Milling, aud
Iron-ores.
— 53 —
Parks, John Randolph, E.M., 1880.
Helena, Mont.
Consulting Mining Engineer.
Parkaoa, Chari,E8 Frederick, C.E. (Life Member), . 1883.
58 William Street, and 145 W. Ninety-seventh Street, New York Citj%
1883-84, Inspector of Construction of Bridges and Railroad Material in Europe.
1884-86, Railroad Engineer in Colombia, S. A, 1887 to date, General Expert Busi-
ness. 1891, Delegate from Colombia to the Inter-Con tineutal Railway Commission at
Washington, D. C.
Parrot, Edward Moore, E.M., 1870.
Ontario, Wayne County, N. Y.
Parsons, George Rowland, E.M., .... 1868.
1870 to 1880, In Nursery BusineRS at Flushing, L. I. 1880 to present time, Secre-
tary and General Manager of tlie The Colorado Springs Co.. and of The National
Land and Improvement Co., of Colorado, with Central Office in Colorado Springs.
Experienced in the development, improvement and sale of lands in Colorado, espe-
cially in and around Colorado Springs, Manitou and Pueblo, also in irrigation works
and growth of trees in Rocky Mountain region. Specialty, Investments in Real
Estate, Mortgages and Mines in Coloi-ado.
Parsons, Henrv, C.E. 1888.
Vice-president City and Suburban Ry., Savannah, Gra., and 1033 Mad-
ison Avenue, New York City.
Parsons, William Barclay, A.B., C.E., . . . 1882.
22 William Street, and 51 Ea.st Fifty-third Street. New York City.
Graduated at Columbia College School of Arts, 1879, with degree of A.B. ; School
of Mines. 188*2, with degree of C.E, ; 1881, Assistant Engineer Blosshurg Coal Com-
pany and Arnot and Pine Creek Railroad ; IS^^-So, New York, Lake Erie and Wes-
tern Railroad ; 1885 to date, Consulting Engineer, New York City. Member Ameri-
can Society Civil Engineers; Member American Society of Mining Engineers;
Member Institution of Civil Engineers (Great Britain).
Payne, Clarence QuiNTARD, E.M., .... 1882.
President Payne Separator Co., 136 Liberty St. and 9 W. Thirtieth
St., New York City.
Pearis, Charles Fowler, E.M., 1884.
Box 374, Helena, Mont.
Peck, Staunton Bloodgood, C.E., M.E., . . . 1886.
Link Belt Machinery Co., Thirty-ninth Street and Stewart Avenue,
Ciiieago, 111., and HI East Thirty-fourth Street, New York Cit}'.
One and a half yeai*s Mechat?ical Engineer, Burr & Dodge, Philadelphia. Two
1888, Assistant Chief Engineer Dmlge Coal Storage Company. Since 1890 and at
pre.sent. Chief Engineer Link Belt Machinery Company, Chicago. Specialty, hand*
ling materials in bulk or package and power transmissions.
Peele, Robert, Jr., E M 1883.
Adjunct Professor of Mining, School of Mines, Columbia College, *' Tho
Monterey," One Hundred and Fourteenth St. and Manhattan Ave.,
New York City.
— 54
1883, Assayer, Desiprnolle Bfeduction Works, Charlotte, N. Carolina. 1883-84, As-
sayer and Assistant Snpt. Silver-Kin^ Mining and Milling Co., Monteznnia. Colorado.
1894-86, Foreman, Dry-crushing and Amalgamating Silver-mill, Silver-King Mining
Co., Pinal, Arizona. 1886, went to England to examine systems of Sewage-disposal
used in inland towns. 1887. Professional work as Assistant, in New York and Ari-
zona. 1888, Examining gold-mines in Republic of Colombia, S. A. Snpt. Mudsill
Mining Co., Ltd., Fairplay, Colorado. Examinations and Ore-testing on Copper and
Tin Properties, New Mexico and North Carolina. 1889, Examining Gold-placers,
Dutch Guiana, South America. 1889-90. Supt. Oregon Gold-mining Co., Cornucopia,
Oregon. 1890-92, Examining Silver-, Tin-, and Gold-mines in Peru, Bolivia, and
Republic of Colombia, S. A., for the Peruvian Exploration Syndicate, Ltd., London,
and Lima, Peru. 1892, Adjunct Prof, of Mining, School of Mines, Columbia College.
Pellew, Charles Ernest, E.M., 1884.
, College Physicians and Surgeons, 437 West Fifty-ninth Street, and 68
East Fifty-fourth Street, New York City.
1884-8o, studied chemistry at. Lehigh University and Bethlehem Steel Works.
18S5-87, studied chemistry, physi(», microscopy and bacteria at School of Mines and
at College Physicians and Surgeons. Private Assistant to Professor Chandler. 1887
to date, Instructor and, later. Demonstrator in Physics and Chemistry at College
Physicians and Surgeons. Hon. Fellow in Applied Chemistry, School of Mines.
Also in general chemical practice with Professor Chandler (as partner). Specialty,
chemical and other expert work, including medical and sanitary questions, e.g^ tox^
icology. Also as patent expert in chemical and physical subjects.
Penmngion, Joheph Pope, A.M. (Associate), . . . 1868.
Morristown, N. J.
Assistant Engineer E. T. V. & G. R.R. 1881-83, Engineer Tombstone Mill and
Mining Company. 1883-84, 1885 et aeq., railroad construction with general con-
tractors. Assistayt Secretary, Louisville, St. Limis and Texas Railway. Resigned
August, 1893. Previous responsibilities in connection with life insurance interests.
Ninth Street and Gowanus Canal, South Brooklyn, and 39 Garden
Place, Brooklyn, N. Y.
1889 to date. New York Tartar Company.
Pierce, Frederick Emery, C.E., . . ' . . 1892.
22 W. Forty-Bfth Street, New York City.
Learner in Baasemer Mill, Maryland Steel Co., Sparrows Pt., Maryland. Draughts-
man, New Jersey Steel and Iron Co., Cooper, Hewitt & Co., New York City.
PiEZ, Charles, E.M., . 1887.
Chief Engineer Link Bfelt Engineering Co., Nicetown, and 430 Frank-
PiSTOR, William, E.M., 1868.
Architect, No. 1 Madison Ave. and 201 W. Fifty-fifth St., N. Y. Oity.
Pitkin, Lucius, A.B., Ph.B., 1881.
138 Pearl Street, New York City.
l,S81-8o, Chemist to Laurel Hill Chemical Works, of Nichols Chemical Company,
Heavy chemicals, especially sulphuric acid. 1885 to date, Analytical and consulting
Chemist, at above address. Specialty, in consulting. Manufacture of acids and
heavy chemicals, treatment of pyrites and copper smelting. Analytical work. Gen-
eral, but special experience in argentiferous and auriferous copper-ores and products.
Microscopical and experimental investigations.
— 55 —
PoLT.EDo, YsiDORO Ygnacio, E.M., .... 1885.
1885, Assistant Engineer, Survey for Water- Works for city of Santiago de Cuba,
1886-89, Assistant Engineer and Principal Assistant Engineer in charge of track and
structures, C&rdenas and Jiicuro R.R., C&rdenas, 1889-90; Manager of Santa Barbara
Sugar Plantation, Biir6. 1694-94, General Manager C&rdenas Sugar Refinery, Gar-
den as.
Porter, Henry Hobart, Jr., E.M., .... 1886.
Westingliouse Electric and Mfg. Co., 120 Broadway, New York City,
and Lawrence, L. I. , N. Y.
1886-87, Fellow in Geology, School of Mines, Columbia College. 1887-88, Sur-
veyor and Assayer Mexican Ore Company, Sierra Mojada, Mexico. 1888-89, Assis-
tant Mining Engineer Batopilas Mining Company, Batopilas, Mexico. 1889-90, Sur-
veyor and Assayer, Duqucsne Mining Company; Assistant Superintendent, Ray &
Poorman mine examinations, same company; Assistant Superintendent Sierrita
County, Arizona, same company. 1890-91, Engiueer with C. W. Hunt Company.
1891 to date, Wescinghouse Electric and Mfg. Co.
Porter, John BoNSALL, E.M., Ph.D., .... 1882.
Proctor- Gamble Co., Ivorydale, Ohio.
Assistant Engineer and Expert in tests of metals for various railways and corpora-
tions. Lecturer on Mechanical Engineering and Metallurgy in University of Cin-
cinnati for some years. At present and for several years past. Engineer Maintenance
of way, C. H. & D. R.R. system. Headquarters, Cincinnati, O.
Post, Abram Skidmoke, C.E., ..... 1884.
173 Madison Avenue, N. Y. City.
Post, Albertson Van Zo,C.E., 1889.
45 Wall Street, and 4 East Sixty-second Street, New York City.
1889-90, Division Engineer, construction, Baltimore and Eastern Shore Rtiilroad.
1891 to date, with the Railroad Equipment Company, of 45 Wall Street, New York
City.
Potter, William Blbecker, A.B., E.M., . 1869.
Profe.ssor Metallurgy and Mineralogy, Washington University, St.
Louis, Mo.
Powell, Frederick, A.B., E.M., 1883.
Charlotte Mineral and Mining Co., Charlotte, N. C.
1883-84, Mechanical Draughtsman and Engineer. 1885, Assayer at Duluth, Examina-
tion and Reports on Mineral Deposits in northeastern Minnesota and Canada, Assayer
and Manager for Sentinel Gold Mining Co. of Minneapolis and Colorado. 1886 to 1888
Superintendent and Manager in Colorado for Denbigh Mining Co. of New York. 1888-
92, Miscellaneous Surveying. 1893, Engineer for Charlotte Mineral and Mining Co.,
Charlotte, N. C. Examining and Reporting on Mines in North Carolina.
Powers, Louis J., Jr., E.M., 1884.
Connecticut River Paper Company, Holyoke, and 4 Mattoon Street,
Springfield, Mass.
1885, Superintendent Vermont Construction Company, St. Albans, Vt. 1886,
Superintendent Standard Pulp Company, Springfield, Mjbs. 1887-88. Assistant
Superintendent Union Manufacturing Company, Holyoke, Mass. 1888 t^ date, Agent
Connecticut River Paper Company, Holyoke, Mass.
— 66 —
t
Prestox, William Evax,-C.E., ... . 1889.
U. S. A. BuiMing, 39 Whitehall Street, and 1427 Washington Avenue,
New York City.
1889 to date, submarine blasting and dredging for U. S. harbor work with grapple,
divers and centrifugal pump.
Provost, Andrew Jacksox, Jr., C.E., .... 1889.
Municipal Building, and 403 Washington Avenue, Brooklyn, N. Y.
1889 to date, Assistant Engineer in Sewage Construction, Department City Works,
Brooklyn, N. Y.
R.
Randolph, John Cooper F., A.B., A.M., E.M., . . 1869.
Consulting Mining Engineer, Mills Building, 15 Broad and 35 Wall
Street, New York City, and 18 Elm Street. Morristown, N. J.
Graduated : Princeton. 1866, and School of Mines, New York City, 1869. 1869-7J,
in Germany, service of U. S. Govt. 1874, in service Japanese Govt. 1884, in Central
China for a Chinese Syndicate. 1887, Resident Manager of La Plata Mines, Republic
of Colombia, S. A. ; National Commissioner of Mines for Tolima, Republic of
Colombia, S. A. 1890, Resident Manager in Borneo of Borneo Diamond Exoloration
Syndicate, Ltd. For 23 years actively engaged in Professional Work in the United
States, Mexico, etc. At different times Member of Council and Vice-president of the
American Institute of Mining Engineers. 1891, sick. 1892, all the year in Mexico
and Colorado. 1893, in Sonora and Virginia, and various other mining matters in
different parts of tlie country.
Randolph, James Fitz, B.S., E.M., .... 1876.
Coinmunipaw Coal Co., Ill Broadway, New York City.
Raymond, Robert Matthew, A.B., E.M., . . . 1889.
Diamond (R) Mining Co., Neihart, Mont.
1880-82. Assistant Assayer, State of Maine Assay Office, Portland, Me. 1882-86,
Assayer and Assistant Superintendent, Haile Gold Mine, S. C. 1886-89. School of
Mines. 1889-90, Assayer and afterwards Assistant Superintendent, Montana Smelting
Co., Great Falls, Mont. 1891, Superintendent, The Diamond Mining Co., Neihart. Mont.
Raynor, Russell, Ph.B., 1889.
42 Bleecker Street, and 114 E. Forty-fifth Street, New York City.
Sept., 18S9, to Aug., 1891, Cliemist, with Martin Kalbfleiscli Sons Co. Sept., 1891,
to April, 1892, Assistant Chemist, Barber Asphalt Co. May, 1892, to date Assistant
Chemist New York Health Department.
Reckhart, Daniel William, E.M. (Life Member), . 1884.
Reckhardt & Heckelman. Assaycre, Box 88, El Paso, Texas.
Reckhart, George Frederick, C.E., .... 1892.
Hotel Lome, Yarmouth, Nova Scotia, Canada, and 500 W. Thirty-
fifth Street, New York City.
Member of "The Southwestern Mining Association " (Incorporated).
Reed, Svlvanus Albert, A.B., A.M., E.M., Ph.D., . 1877.
Rialto Building, Chicjij^o, and Union Club, Chica<ro, 111.
1878, Secretary to Assistant Commissioner General, Paris Exposition. 1879, Lec-
tured on Chemistry. Reported on Mine^ in Colorado. 1830^4, Superintendent and
part Proprietor, Sampling and Cancentratioa Works in Colonido, and Reported on
Mines there and in Idaho and in the South. 1886, Consulting Practice in New York,
— 57 —
Pfttoiit Ex|>ert work and on Dredgiug in New York Hurbor. 1836-91, Superintend-
ent Inspection Department of Fire Insarance Co. (Commonwealth, of New York).
1893, Expert for New Insarance Bating, Mercantile Section of Boston. May, 1893,
appointed Manager Western Factory Insurance Association. Special Agent Western
Department of Continental Insurance Co.
Rees, John Krom, AB., A.M., E.M. (Life Member), . 1875.
Prof. Geodesy, Practical Astronomy, and Director of Observatory, •
Columbia College, and 1 W. Seventy-second St., New York City.
Assistant in Mathematics, School of Mines, 1873-76. Professor of Astronomy and
Mathematics, Washington University, St. Lonis, Mo., 1876-81. Member Fort Worth
Solar Eclipse Party, July, 1878. Instructor in Geodesy, etc., Columbia Collei^e, 1881-
82. Adjunct Professor in Geodesy, etc., Columbia College, 1882-84. Professor in
^Geodesy, etc., Columbia College, 1884 to date. Director of Observatory, Columbia
College, 1881 to date. Chairman of Board of fklitors, School of Min£8 Quabterly,
1883-90.
Renault, George, C.E., • . . . . . 1883.
61 Irving Place, New York City.
Restkepo, Camilo Claudio, E.M., C.E., . . 1887.
D. Delastro & Co., 54 William St., and Box 1609, New York City.
RaoDEs, Francis Bell Forsyth, E.M., . . 1874.
National S. & R. Co., South Chicago, 111., and Quebec, Canada.
May, 1875, to December, 1876, Surveyii»g Corps, Coxe Bros., Driftoii, Pa. January,
1877, to May, 1878, Assistant Superintendent, Soutli American Mining Co., Venezuela.
November, 1878, to June, 1879, Working at Lead Mine. Canada. October, 1879, to
April, 1880, Laborer, Ontario Mill, Park City, Utah. April, 1880, to July, 1881, Assist-
ant Superintendent, Minge Furnace Co., Utah. August, 1881, to January, 1882,
Assistant Superintendent St. Helena Mine, Sonora, Mexico. January, 188*2,
to April, 1883, Assistant Superintendent, Tombstone M. and M. Co., Arizona. May,
1883, to December, 1883, Superintendent, Bamsliam Smelting Furnace, Idaho. Jan-
nary, 1884, to May, 1885, Assistant Superintendent, Minge Furnace Co., Utah. June
1885, to December, 1885, Foreman of Blast-furnac9 Department, Kansas City S. and
B. Co. Octolier, 1886, to December, 1889, Superintendent, Chicago Works, Chicago
and Aurora S. and R. Co. January, 1890, to date, Superintendent National S. and R.
Co., South Chicago.
Rhodes, Robert Dunn, E.M., 1879.
Supt. Arkansas Valley Smelting Works, Leadville, Col., and Box 726,
1879-80, Foreman, Germania Smelting Co., Salt Lake City. 188D-82, Night Fore-
man, Ontario Silver Mining Co., Park City, Utah. 18vS2-83, Superintendent, Tomb-
stone M. and M. Co. Reduction Works, Charleston. 1883-84, Mill Foreman, St.
Helena Gold and Silver Mine, Sonora. 1884-85, Assisfcint Superintendent, Billing
Smelter, New Mexico. 1885-86, Assistant Superintendent, Viola M. and S. Co., Idaho.
1887-88, Assistant Superintendent, Anglo-Mexican Mining Co., Yedras, Mexico. 1889
-91, Gcneml Superintendent, Dnquesne M. and R. Co., and Sicrrita County, Arizona.
1891-92, Engineer Eraser & Chalmers, City of Mexico. 1892-94, Supt. as above.
Rice, George Samuel, Jr., E.M., 1887
119 S. Market Street, and 432 N. Court Street, Ottumwa, Iowa.
1887, Assistant Field Engineer, Colonida & Utah Railway. 1888-89, Assistant
Mining Engineer of Colorado Fuel Co. 1890 to date. Mining Engineer of VViiitebreast
Fuel Co.
— 58 —
Rich, Jacob Monroe, E.M., C.E. (Life Member), . . 1883.
50 W. Tliirty-eighth Street, New York City.
Rechardson, John Clarence, E.M., C.E., . . . 1883.
RiCKETrs, Pierre dePeyster, E.M., Ph.D., . . .1871.
Professor, Analytical Chemistry, Columbia College, School of Mines,
and 115 E. Seventy-ninth Street, New York City.
1868, Assistant, General Chemistry, Columbia College. 1871-72, Assistant in Min-
eralogy and Metallurgy, School of Mines. 1872-75, Assistant in Assaying, School of
Mines. 1875-80, Instructor in Assaying, School of Mines. 1886 to date, Professor of
Assaying, School of Mines. Since graduation also engaged in general Mebillargical,
Chemical and Mining Engineering work.
RiusDALB, Thomas Weddle, E.M., . . . . 1883.
n. R. Worthington, 145 Broadway, New York City, and Mont-
clair, N. J.
Assistant Superintendent of the Ruby Durango Mine, and Wilder-Macdonald Con-
centrating Mill to 1834. Superintendent of the Wilder-Macdonald Mill, 1884. From
1888 with the Worthington Pumping Engine Co. From June, 1889, as Secretary of
the Company.
RiEs, Hbnrich, Ph.B., . 1892.
Care of Prof A. J. Moses, School of Mines, Columbia College, New
York City.
Summer of 1891 and 1892, on New York Geological Survey. October, 1892, to
August 1st, 1893, Assistant Director, New York Scientific Exhibit at World's Fair.
July 1st, 1893, to July 1st, 1894, Fellow in Mineralogy, Columbia College.
RoESER, Frederick, B.S., E.M., 1884.
240 West 130th Street, New York City.
Rogers, Oscar Legar£, Ph.B. (Arch.), .... 1889.
No. 1 Madison Avenue and 57 West Eighty-fifth Street, New York City.
1889-92, in Europe. 1893, Architect as above.
RoLKER, Charles M., E.M. (Life Member), . . . 1875.
1868-70, At Royal School of Mines, Clausthal, Germany. 1871-72, Working practi-
cally in Iron Mines of Hibernia and Mt. Pleasant, N. J., Wisconsin Lead Mines and
Iron Mines of Lake Superior. 1872-75, At School of Mines, Columbia College. 1876,
Asaayer at Allouez Copper-dressing Works, Lake Superior. 1877, Mining Engineer
to the Mariposa Land and Mining Co., Mariposa Co., Cal. (Gold). 1878, Superintend-
ent, Brooklyn Company, Washoe Co., Nevada (Base Metal). 1879, Superintendent.
Stormont Silver Co., Silver Reef (Silver). 1880-82, General Manager, Chrysolite S.
Mg. Co., Leadville, Colo. (Lead Carbonates). Siuce then to date, in General Con-
sulting Practice as Mining Engineer and Metallurgist, Examining Mines, Mills and
Placers, in the United States, Old Moxico, Central America. South America and East
Indies. Specialty, Precious and Base Metals other than Iron. 1891-92, Cons. Engr.
to the British South African Company in its sphere south of Zambesi.
Rood, Roland GouvERNEUR, Ph.B., , . . . 1884.
Care Prof. 0. N. Rood, Columbia College, New York City.
— 59 —
Rosenthal, Albert, C.E., 1892.
158 East- Seventy-ninth Street, New York City.
Rowland, Charles Bkadlky, C.E., .... 1884.
Continental Iron Works, Greenpoint, Brooklyn, N. Y., and 329 Madi-
son Avenue, New York City.
Rowland, George, C.E., 1887.
Continental Iron Works, Greenpoint, Brooklyn, N. Y., and 329 Madi-
son Avenue, New York City.
Rupp, Philip, Ph.B., M.D., . . . . . . 1884.
84 Second Avenue, New York City.
1884-87, Student in Medicine, College of Physicians and SurReons, N. Y. 1887-88,
House Physician and House Surgeon, St. Francis Hospital, N. Y. 1883 to date, Prac-
ticing Physician.
Ruttmann, Ferdinand, Jr., E.M., .... 1880.
Ryon, Augustus Meader, E.M., ..... 1886.
President and Prof. Engineering, College of Agriculture and Mechanic
Arts, Bozeman, Montana.
1886-87, Assistant Engineer on New London Wat«r Works. Assistant in Metal-
lurgy, School of Mines, Columbia College. 1837-88, Assistant to F. N. Owen, Civil
and Sanitary Engineer, New York City. 1888-91, Professor of Engineering and Min-
ing, School of Mines, College of Montana, Deer Lodge, Mont. 1892 to date. President
and Professor of Engineering, Montana College of Agriculture and Mechanic Arts,
Bozeman, Montana.
s.
Sage, Edward Eugene, C.E. (Life Member), . . . 1877.
United States Assay OflBce, 30 Wall Street, New York City, and 77
Hillside Avenue. Orange, N. J.
I have been connected with this office since February, 1879, and have consequently
no outside experience except in electricity, being President of the Essex County
Electric Co., of Orange, N. J., and in Analytical Chemistry.
Sakds, Ferdinand, A.B., Ph.B., 1882.
Drugs and Assaying Supplies, Box 1172, Butte, Mont.
Schermerhokn, Fkederick Augustus, E.M. (Life Mem-
ber), 1868.
41 Liberty Street, and 61 University Place, New York City.
ScHiEFFELiN, WiLLiAM Jay, Ph.B., Ph.D. (Muiiich), . 1887.
Schieffelin & Co., 170 William Street, and 35 West Fifty-seventh St. ,
New York City.
Schneider, Albert Francis, E.M., C.E. (Life Member), 1876.
Care of Great Falls Smelting Co., Monterey, Mexico.
1876-1877, In Europe visiting Smelting and Dressing Works. 1878, Chemist and
Assayer Germania S. and B. Co., Salt Lake City, Utah. 1879, Foreman, Assistant and
Superintendent Germania S. and R. Co., Salt Lake City, Utah. 1880-'83, Superin-
tendent Germania S. and R. Co., Salt Lake City, Utah. 1883-85, Superintendent G.
Billing Smelting Works. Socorro, N. M. 1885-87, Superintendent Kansas City S. and
— 60 —
E. Co., Arjfentine, Kansas. 1887, Connected with the Rio Grande S. Co., Socorro, N. M.
1887 to 1893, General Manager St. Lauis S. and B. Co., St Louis, Mo. Superintendent
Great National Smelting Co., Monterey, Mexico.
SciiROEDER, Jamfvs Langddn, C E., . . . . 1889.
Member of firm of* Parrish & Schroeder, Architects, 1 Madison Ave.,
New York City.
July, 1890, to January, 1894, with Benwick, Aspenwall & Benwick, New York
City, as Architectural Draughtsman.
ScHROTER, George Austin, E.M., .... 1893.
1525 Blake Street, Denver, Colo.
Superintendent Keystone and Manager Logan Group Mines, Colorado.
Schumann, Charles Henry, C.E., .... 1888.
Room 187, 68 Broad Street, New York City, and 349 Sixth Avenue,
Brooklyn, N. Y.
1888. May, 1890, Assistant Engineer Chesapeake and Ohio Railway Co., Cincinnati,
charge of Real Estate, Bight of Way and Track and Construction work. May to Au-
gtist, 1890, Assistant Engineer to H. Alher. C. E., Birmlngliam, Ala., General Engi-
neering. August, 1890 to March, 1891, Assistant Enoiineer Chesapeake and Ohio
Bailway Co., charge of subdivision of Town of Wtist Clifton Forge, Va., and Bight of
Way on line of road. 189*2-93, Assistant Engineer Long Island B. B., and Engineer for
Ferris & Richards Contractors for Bailroadsand Waterworks, at 98 Hudson St.. Jersey
City, N. J., to date with J. James B. Cores, C.E., Waterworks Supply and Sewerage.
Seligman, Joseph Guy, E.M., 1887.
Mining Superintendent, and 69 W. Ninety-fifth St., New York Citj'.
Share, William Waldemar, Ph.B., Ph.D., . . . 1881.
1881, Superintendent Columhia Chemical Works, Brooklyn, N. Y. 1881 to 1888,
Assistant Physics, Columbia College. 1888, Consulting Electrician, Department of
Public Parks, Brooklyn, N. Y. 1889 to date, Professor of Chemistry, Adelphi Acad-
emy, Brooklyn, N. Y.
Sherman, Frank Dempster, Ph.B., .... 1884.
Adjunct Professor of Architecture, School of Mines, Columbia College,
New York City.
Shriver, Henry Tower, Ph.B., 1888.
T. Shriver & Co., 333 E. Fifty-sixth Street, and G86 Park Avenue,
New York City.
In Iron Foundry and Works, as above since graduation,
SiMONDS, Francis May, E.M., Ph.D., .... 1887.
Assistant in Assaying, Columbia College, School of Mines, and 147 E.
Thirty-fourth Street, New York City.
Singer, George, Jr., EM., 1880.
Ill Fourth Avenue, Pittsburgh, Pa.
Singer, George Ha RTON, E.M., 1880.
Singer, Nimick & Co., and 17 Park Street, Allegheny, Pa.
Skinner, Elmer, C.E., 1891.
227 Cumberland Street, Brooklyn, N. Y.
— 61 —
Slack, Charles GrODDARD, E.M., 1884.
Everett, Wash., and Marietta, Ohio.
Slade, Richmond Edward, Ph.B., .... 1887.
White Plains, N. Y,
1887, Assistant Saperintendent United Gas Improvement Co., Yonkers, N. Y.,
Plants. 1888, Superintendent Gas Department, Asheville (N. C), Light and Power
Co. 1889, Superintendent Gas and Electric Plants, Citizens' Gas Light Co., Jackson,
Tenn. December, 1889 to date. Secretary, Superintendent and Trustee Citizens Gas
and Electric Co., White Plains, N. Y.
Smith, Augustus, A. B., C.E, 1889.
136 Liberty Street, and 460 W. Forty-fourth Street, New York City.
Summer of 1886, Land Surveying ^in charge of Party). July to November, 1889,
Draughtsman, Link Belt Engineering Co., Nicetown, Phila. November, 1889-91, Chief
Draughtsman, New York Office Link Belt Engineering Co. 1891-92, out of Profes-
sional work. 1892, Salesman and Engineer as alcove. 1893, private practice as Engi-
neer and Contractor.
Smith, Frank Marshall, E.M., . . . . . 1889.
Supt. United Smelting and Refining Co., Smelter, Mont.
1889-1890, On the United States Geological Survey, engaged in hydrographic work
on the Irrigation Survey and triaugulation on the Topographic Survey, in Idaho and
Oregon. 1891, Assayer Colorado Smelting Co., Pueblo, Colo. October, 1892-93,
Assistant Superintendent. 1893, to date, Supt. United Smelting and Refining Co.,
Smelter, Mont.
Smith, Francis Pitt, Ph.B., 1888.
Mamaroneck, N. J.
Analytical Chemist in Leather trade, 1888-'89. Superintendent Chemical Works,
Wm. H. Swift & Co., East Boston, Mass., 1889-'90. Consulting Chemist, Dening <& Logan,
58 William Street, 1890. Assistant Chemist New York City Health Department, 42
Bleecker Street, 1890-92. Specialty, Chemical Mechanics. 1892-93, Inspection
Brooklyn Navy Yard.
Smith, Lenox, A.B., A.M., E.M. (Life Member), . . 1868.
Smith, William Allen, E.M., 1868.
52 Wall Street, New York City, and Pelliam Manor, N. Y.
Smyth, Charles Henry, Jr., Ph.B., .... 1888.
Professor of Geology, Hamilton College, Clinton, N. Y.
1888-89, Chemist Franklin Iron Mfg. Co. 1889-90, Geological Field Work in New
York, Alabama, Georgia, and Tennessee. Jane, 1890, received Degree of Doctor of
Philosophy from Columbia College. 1890-91, studied Petrography and Mineralogy
with Prof. Rosenbusch at ihe University of Heidelberg. 1891, appointed Professor
of Geology in Hamilton College. Engaged in the study of the Western Adirondack
region, and the investigation of Problems in Central New York. Chiefly in Petro-
graphic, Chemical and Glacial Geology.
Snook, Thomas Edward, E.M., 1884.
Arulutect, 12 Chambers Street, New York City.
1884-87, Supt. Cons, for John B. Snow, Architect. 1887, to date, Architect.
Southard, George Carroll, C.E., .... 1892.
114 Brooklyn Avenue, Brooklyn, N. Y.
— 62 —
June, 1892, to March, 1893, Equity Gas-Works Construction Co., Brooklyn, E. D.
March, 1893, to January, 1884, with Heine Safety Boiler Co. January, 1894, to date,
with Heck er- Jones- Jewell Milling Co.
Spooner, Allen Newhall,C.E., 1886.
Department of Docks, Pier A, North River, New York City, and 186
Carteret Avenue, Jersey City, N. J.
July, 1886 to August, 1887, Rodman and Draughtsman, Penn B.R., Jersey City.
August, 1887 to May, 1890, Hydrographer Department Docks, New York City. May,
1890-1891 to present time, Assistant Engineer Department Docks. New York City.
Specialty, Railroad Engineering. River Submarine and Harbor Engineering.
Stanton, Fkank McMillan, E.M., .... 1887.
Superintendent Atlantic Mine, Hougjiton Co., Mich.
1887-1888, Superintendent pro tern. Central Mine, Mich. 1888-1S89, Engineer At-
lantic Mine, Mich. 1889 to date. Superintendent Atlantic Mine, Mich.
Starek, Emil, LL.B., LL.M., E.M., .... 1885.
Keller & Starek, Patents, Iloom 303 Times Building, Broadway, and
2730 Ellendale Avenue, St. Louis, Mo.
1885-1887, Assistant in United States Geological Survey. 1887 to 1892, Assistant
Examiner United States Patent Office, Washington, D. C.
Starr, Chandler Dann AT, C.E., 1881.
Staunton, John Armitage, Jr.. E.M., A.B. (Harvard), , 1887.
232 W. Forty-fifth Street, New York City.
1887-88, Instructor in Mathematics. Rochester, N. Y. 1888-90, Student in Har-
vard University. 1890-92, Student in the General Theological Seminary, N. Y.
1892-93, in charge of Church of the Holy Trinity, Wallace, Idaho. 1893, Assistant
at Church of St. Mary the Virgin, New York City.
SfAUNTON, William Field, E.M., 1882.
Superintendent Tombstone Mill and Mining Co., Tombstone, Arizona.
1882, Assayer and Assistant Superintendent Vermont Copper Co., Ely, Vt. 1882,
Assayer and Accountant Dunn Mt. (iold Mine, Salisbury, N. C. 1883, Assayer Le-
doux & Ricketts, N. Y. 1883, Constructing Engineer, C. M. and R. Co., N. Y. 1883,
Assistant to Manager of Mills and Smelter of T. M. and M. Co., Tombstone, Arizona.
1884, Consulting Engineer, N. Y. 1884, Mining Engineer, for T. M. and M. Co., Tomb-
stone, Arizona. 1890, to date, Superintendent Tombstone Mill and Mining Co.,
Tombstone, Arizona. Specialty, Gold and Silver Mining and Mettillurgy.
Stearns, Thomas Bbai.e, E.M., 1881.
Mining Machinery, Denver, Colo.
SroNE, George Cameron, Ph.B., 1879.
New Jersey Zinc and Iron Company, Newark, N. J.
1879, Chemist, Booth & Edgar Sugar Refinery. 1879-82, Chemist with Potter &
Riggs, St. Louis, Mo. 1882-91, with New Jersey Zinc and Iron Company, Newark,
N. J., first as Chemist; since 1884, as Superintendent Blast-Furnaces.
Struthers, Joseph, Pii.B., 1885.
Tutor in Metallurgy, Columbia College School of Mines, and 624
East One hundred and thirtj^-sixtli Street, New York City.
1885-88, Fellow in Mineralogy. 1880-90, Assistant in Mineralogy and Metallurgy.
1891, to date, Tutor in Metallurgy Columbia College, School of Miues.
— 63 —
Stuart, Wilijam Henry, C.E., 1886.
47 Liberty Street and 36 W. Seventielh St., New York Citj-.
1886, on rail tray surveys in Minnesota and Wisconsin with C. B. & N. E.R. Co.
1887-89, Fellow in Engineering and Assistant in Snmmer School of Surveying,
School of Mines, Columbia College. 1889-90, making surveys and superintending
construction at the Hudson River State Hospital, Poughkeepsie, N. Y. 1890, on sur-
veys in the West Indies. 1893, in general practice.
SuTER, George Augustus, E.M., 1883.
G. A. Suter & Co. , Engineers and Contractors, 139 South Fifth Ave-
nue, New York City, and 206 Marcy Avenue, Brooklyn, New York.
1884-92, Engineer, Baker. Smith & Co. 1892 to date, as above.
Swain, Alfred Ernest, E.M., . . . . .1881.
Supt. Trinidad Mining Co., Copala (via Mazatlan, Sinaloa, Mexico,
and 902 Prospect Street, Cleveland, 0.
1881-84, railroad work in Mexico. •1886-J-8, City Engineer's Department, Kansas
City, Mo., in charge of sewer work. 1889-91, mining work in Mexico. 1891, Snpt.
San Buenaventura Mining Company, Santa Lucia. Sinaloa, Mexico, via Mazatlan
and Pnnna. 1891-93, Supt. Trinidad Mining Co.
T.
Temple, Skth Justice, Pu.B., 1892.
Winona, Minn.
Instructor in Architectural Drawing Art Schools of the Metropolitan Museum -of
Art, Fifth Ave. and Thirty-Second Street, New York City.
Terhune, Richard Henry, E.M., 1870.
417 West Temple Street S. Salt Lake City, Utah.
1870, Assistant to late J. W. Foster, geology of coal fields, Indiana. 1871, Griswold
Steel Works, draughting, blowing steel, etc. 1872-77, Joliet St«el Company, draught-
ing, inspecting steel rails and exploration of Callaway County, Missouri, for coal and
iron. 1877-80. Superintendentand Assistant Superintendent Smelting Works in Utah.
1880-93, General SuperintendentHanauerSmelting Worki, Utah. Specie 1 1}^ construc-
tion and operation of lead smelting works. Resigned above position September, 1893.
Thacher, Arthur, C.E., E.M., 1877.
1227 Spruce Street, St. Louis, Mo.
1878-79, with Progreso Mining Company, Trimfo, Lower California, Mexico,
1879-83, Southern Arizona and Northern Mexico Mining and Milling. 1883-87,
office in New York. Examining and reporting ou mines and mills. 1887 to date,
with Professor W. B. Potter, at St. Louis Sampling and Testing Works and Washing-
ton University. Lecturing on Metallurgy. Testing ores, etc. Examining and re-
porting on mines and mills. Superintendent Central Lead Co.
Thomas, Frederick Mavhew, E.M., .... 1885.
20 City Hall, Syracuse, N. Y., and Box 204, Skanentelea, N. Y.
Leveller (Instrument man, etc.), on New York State Canals, from September, 1887
to November, 1889 (position resigned). Transit-man and leveller on preliminary
railroad survey in Schoharie County, in spring of 1890. Transit-man and leveller on
Syracuse water works during the winter of 1890-91.
Thompson, Henry Clark, C.E., 1886.
Lorillard Place, and One hundred and eighty-seventh and One hun-
dred and eighty-eighth Streets, New York City.
— 64
TiBBALS, George Atwater, C.E., 1883.
Continental Iron Works, and 148 Milton Street, Brooklyn, N. Y.
1883 to date, as above.
TiBBALS, Samuel Gaylord, C.E., 1884.
Continental Iron Works, and 148 Milton Street, Brooklyn, N. Y.
1884 to date, as above.
TiLDEN, George Cyrus, C.E., 1876.
State School of Mines, Golden, Colo., and 310 Closson Avenue, Brook-
lyn, N. Y.
1876-80, City Surveyor, Brooklyn, N. Y. 1880-81, Superintendent Dunderberg
Mining Company, Georgetown, Colo. 1881-82, Clieiuist and Assayer, Denver, Colo.
1882 to date, Professor Analytical Chemistry State School of Mines, Golden, Colo.
1881 to date. Consulting Practice as Mining Engineer. Specialty, Analytical Chem-
istry and Assaying.
Titus, Warren Harriott, E.M., 1885.
Assisting Sanitary Engineer New York Board of Health, New York
and Whitestone, N. Y.
T0NNEL6, Theodore, Ph.B, 1880.
Care of Wm. Dewees Wood Co., McKeesport, Allegheny Co., Pa.
In charge of Refining and Steel Departnicjits of the Wm. Dewees Wood Company.
ToRREY, Charles Herbert, Ph.B., .... 1880.
1880-83, Assistant in Qualitative Laboratory, School of Mine^. 1883-85, teaching
in New York Institute for Improved Instruction to Deaf Mutes, New York City.
1885-87, in the employ of the DuBois Manufacturing Company of New York, in their
branch in London. 1887 to present, managing German branch of BuBois Mauufac-
Tower, Albert Edward, E.M., ...... 1883.
Poughkeepsie Iroti Company, Poughkeepsie, N. Y.
Tower, Frederic Wetherwax, E.M., .... 1887.
Assistant Examiner, Room 223, Patent Office, and 1400 L St., N. W.,
Washington, D. C.
1888 to date, as above.
Traphagen, Frank Weiss, Ph.B., Ph.D., . . 1882.
Professor Analytical and Applied Chemistry, College of Montana,
Deer Lodge, Montana.
1883-84, Chemist for Williams, Clark & Co., Fertilizers. 1884-87, Instructor in
Ciiemistry and Physics, Staunton Military Academy, Staunton, Va. 1887, Professor
of General, Analytical and Applied Chemistry and Assaying in the College of Mon-
tsnia and Montana School of Mines. 1884-87, Analytical and Consulting Chemist,
Staunton, Va. 1887, Principal work, fertilizer, iron and steel, clays, etc. Analytical
and consulting Chemist and Assayer, Deer Lodge, Mont. Assaying, miscellaneous
analysis and legal work. 1890, Assayer for the Champion Consolidated Mining Com-
pany, Deer Lodge, Mont.
Trask, George Francis Do.vnell, E.M., . . 1887.
R. W. Hildreth & Co., 2 Wall Street, New York City.
— 65 —
1888-90, Apprentice and Machinist, L. & N. Bailroad. 1890-91, Draughtsman, L. &
TUSKA, GUSTAVE RoBITSCHER, B.S., M.S., C.E., . . 1891.
41 East Forty-ninth Street and Santa Margheretta, 1125 Madison Ave.,
New York City.
1892-93, Bridge Engineer, Long Island Bailroad. Assistant Engineer C. N. Y. and W.
R.B. in charge of Stony Brook viaduct, 1893. Consulting Engineer Port-au-Prince
By., Cuba, 1893. Assistant to Professor of Civil Engineering, Colnmbia College, 1893.
TuiTLE, Edgar Granger, E.M ., 1881.
Box 109, Eagle Pass, Texas, and San Felipe, Coahuila, Mexico.
1881, Assistant Engineer, Tilly Foster Iron Mine, Brewster, N. Y. 1881-82, Divi-
sion Engineer, Wheeling & Lake ErieR. B., Toledo, O. 1882-83, Assayer and Mining
Engineer. Silver City, New Mexico. 1883-85, Division and Office Engineer, Arizona
& New Mexico Railroad, Lordsburgh, Arizona. 1885, Constructing Engineer at Mines,
Arizona Copper Co., Clifton, Arizona. 1885-89, Mining Engineer, Cambria Iron Co.,
Johnstown, Pa. 1889 to date, Superintendent, Alamo Coal Co., and Coahuila Coal
Co., San Felipe, Coahuila, Mexico, or Box 109, Eagle Pass, Texas.
Tyler, Walter Lincoln, C.E., 1887.
116-120 Front Street, and 1314 Pacific Street, Brooklyn, N. Y.
1887, Levelman and Transitman on the Roanoke & Southern Railroad, Ya. 1888,
With J. A. Latham, C.E., Providence, R. I. 1888-89, With F. N. Owen, E.M., Sanitary
Engineer, New York City. 1889 to the present time. With The A. B. See Manufac-
turing Co., 116-120 Front Street, Brooklyn.
V.
Value, Beverly Reid, E.M., 1884.
Vanderpoel, Frank, E.M., 1875.
Chemist, The Celluloid Co., 295 Ferry St., Box 55, and 191 Roseville
Avenue, Newark, N. J.
1875-78, Salesman, with E. B. Bepjamin. 1878 to date, as above.
Van Arsdale, William Henry, A.B., A.M., E.M., 1868.
Vice-President, Chicago and* Aurora Smelting and Refining Co.,
Chicago, m.
Van Blarcom, Elbert Champlin, C.E., . 1876.
Hidalgo, Mexico, Care H. de San Francisco Pachuca, and State Min-
ing Bureau, Box 2085, San Francisco, Cal.
Yan Cortland r, Edward Newenham, E.M., . 1885.
Tuxedo Park, N> Y.
Van Dyck, Edwin, Ph.B., 1888.
Box 61, Arlington, N. J.
Van Sinderen, Alvan Howard, Ph.B., . • 1881.
Attorney and Counselor- at- Law, 15 Broad Street, and 29 Washing-
ton Square, New York City.
Van Volkenburgh, Edward, Jr., C.E., . . . 1888.
Morgan & Bartlet, 41 Wall St., New York City.
5
— 66 —
Van Wagenen, Theodore Francis, E.M., . . . 1870.
Consulting Engineer; President and General Manager of The Deming
Ore Co., Deming, Grant County, New Mexico.
VoLCKENiNG, GusTAV JuLius, Jr., Met. Eng., E.M., . 1888.
675 Lafayette Avenue, Brooklyn, N. Y.
VoNDY, Rudolph Harrison, E.M., .... 1882.
305 Montgomery St., Jersey City, N. J.
1882-83, Assistant Engineer, Tilly Foster Iron Mine. 1885-92, Chemist Phoenix
Iron Works, Phoenixville, Pa. 1892, Supt. Plenty HortM and Skylight Works.
Von Nardroff, Erkest IIobert, E.M., . . . 1886.
Instructor of Physics, Barnard College, 343 Madison Avenue, New
York City, and 2G2 Penn Street, Brooklyn. N. Y.
VuiT]6, Hermann T., Ph.B., Ph. D., . . . .1881.
Assistant in Quantitative Analysis, School of Mines, New York City,
and New Rochelle, N. Y.
1881-2, Superintendent Columbia Chemical Works, Brooklyn, N. Y. 1883-91, As-
sistant Instructor in Analytical Chemistry, School of Mines. Engaged in investigat-
ing new Analytical Methods. Specialty, Commercial Organic Analysis, Expert in
Oils, Fats, Soap, etc.
w.
Wainwright, John Howard, Ph.B., .... 1882.
Chemist, 402 Washington Street, New York CitJ^
Walker, Arthur Luci EN, E.M., 1883.
Keyser Building, Baltimore, Md., and Lock Box 56, Morristown, N. J.
1883-84, Chemist and Assayer, Old Dominion Copper Co., Globe, Arizona. 1885,
Assistant Superintendent of same Co. 1886, Engaged in connection with Iron Metal-
lurgy in New York City. 1887, Mechanical Engineer for Silver King Alining Co.,
Silver King, Arizona. 1888-93, Superintendent, Old Dominion Copper Co., Globe,
«
Arizona. Also report on all classes of Mining and Metallurgical Property in Arizona.
1893, Consulting Engineer Old Dominion Copper Co., Arizona, and General Manager
Baltimore Electric Refining Co.
Wallace, William Jefferson, Ph.B., . . . 1886.
Architect, Whitestone, N. Y.
Waller, Elwyn, A.B., A.M., E.M., Ph.D., . \ . 1870.
33 West Fifteenth Street, New York City.
Wampold, Leo, Ph.B., 1888.
204 Monroe Street, Chicago, 111.
Ward, Delancy Walton, Ph.B., 1888.
Whit<?stone, N. Y.
Warner, Joseph Lowrey, E.M., 1887.
410 Bailey Building, Seattle, Wash.
August, 1887, to August, 1883, Omaha and Grant Smelter, Denver, Assistant
Assayer. August, 1888, to July, 1889, Examination of and Reports on Mines in
CcBur d'Almes, Idaho, and in O'Kanagan Mining District, Washington. Manager,
La Belle vue Mine, same district. July, 1889, to January, 1890, Assistant Superin-
tendent and Amalgamator, Golden Monarch Mine, Oregon. January, 1890-92, Ex-
iuuination and Reports on Mines in Western Washington. Manager, Culver Mining
— 67 —
Co. and V. P. Vermilion Iron Co. 1892, Examinations in C^cade Range. .1893. Ex-
aminations of Iron Deposits, Island of Texada, British Columbia.
Watson, Frederick Morgan, E.M., . . . 1885.
Mina Rayo, Casapalca, Peru (via Lima), and 403 Sibley Street, Cleve-
land, 0.
1885, Assayer and Surveyor, La Maria Mining Co., Mexico. 1886-89, Engineer,
Mill Superintendent, Sombrerete Mining Co., Mexico. Concentration and Lixivia-
tion. 1890, Engineer for Peru Exploration Syndicate, Ltd., Peru. 1891 to date. Exam-
ining Engineer for Frecheville Bros. Special Experience in Roastiug Rebellious
Ores. Lixiviation by Russell Process and Superintendent as above.
Watson, Rolla Barnum, Met. Eng., .... 1891.
Park City, Utah, and 403 Sibley Street, Cleveland, Ohio.
Assayer, Candemena, Mexico, 1891. Supt, Erection of Power Plant for Electric
Street R. R., Atlanta, Ga., 1892. September, 1893, with Dewey-Walter Refining Co.,
Marsac Mill, Park City, Utah.
Wedekind, Edwin Hutter, Ph.B., .... 1889.
Lebanon, Pa,
Weed, Walter Harvey, E.M., 1883.
U. S. Geological Survey, Washington, D. C, and care S. R, Weed,
South Norwalk, Conn.
1883 to date. Geologist on the U. S. Geological Survey. 1883-89, general geology
of the Yellowstone National Park, especially of sedimentary rocks, with examina-
tions of the adjacent mining regions. 1890, structural and economic geology of the
country north of the Yellowstone Park, with special studies of the coal-fields of
Montana. Specialty, economic and stratigraphic geology. Publications: "A Deadly
Gas-spring in the Yellowstone National Park." — Science. " The Diatom-beds and
Marshes of the Yellowstone National Park." — Boi. Gazette. " The Formation of Hot
Spring Deposits." — Ninth Annual Report of the Director U. S. Geological Survey.
"Geysers." — S | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4202536344528198, "perplexity": 23075.179752795964}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-18/segments/1461860126377.4/warc/CC-MAIN-20160428161526-00115-ip-10-239-7-51.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/chain-shape-euler-lagrange-equations.195340/ | # Chain shape (Euler-Lagrange equations)
1. Nov 1, 2007
### neworder1
A chain with uniform linear density d and length L is tied at two ends to the ceiling. How to find its shape using Euler-Lagrange equations? (I know it can be done with other methods, but I want to know how to do it using E-L).
2. Nov 1, 2007
### siddharth
First of all, you need to know what quantity is to be minimized. Next, you'll also have to consider the constraint (in the form of an integral) that the total length of the chain is L. So, use a lagrange undetermined multiplier so that you have the functional $g = f + \lambda f_1[/tex], where f is the integrand which needs to be minimized and [itex]f_1$ is the constraint. If you apply the Euler Lagrange equations to g, you'll be able to get the shape of the chain. To find $\lambda$, you'll need to use the constraint. Can you solve it from here?
3. Nov 1, 2007
### Dick
Actually, I don't think it can be done without E-L. How would you do it?
4. Nov 2, 2007
### neworder1
Yes, it can be done without E-L "manually", i.e. by writing forces, angles etc., but it's a very tedious way. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9209146499633789, "perplexity": 387.6562064677368}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-04/segments/1484560279657.18/warc/CC-MAIN-20170116095119-00082-ip-10-171-10-70.ec2.internal.warc.gz"} |
http://mathhelpforum.com/algebra/42782-help-solving-log.html | # Math Help - Help with solving a log
1. ## Help with solving a log
I am stuck on this one. Can someone show me the steps tp solve it. Thanx
100(1.02)^x/4 =200
2. Originally Posted by whiteowl
I am stuck on this one. Can someone show me the steps tp solve it. Thanx
100(1.02)^x/4 =200
$100(1.02)^{x/4} = 200$ .............divide by 100
$\Rightarrow (1.02)^{x/4} = 2$ ..................log both sides
$\Rightarrow \ln (1.02)^{x/4} = \ln 2$ ..............apply the rule $\log_a (x^n) = n \log_a x$
$\Rightarrow \frac x4 \ln 1.02 = \ln 2$ ............now solve for $x$, $\ln 1.02 \mbox{ and } \ln 2$ are just constants, and can be treated as such | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 7, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9735217094421387, "perplexity": 1245.9356298557536}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-18/segments/1429246656747.97/warc/CC-MAIN-20150417045736-00243-ip-10-235-10-82.ec2.internal.warc.gz"} |
http://danielscully.co.uk/projects/mathml-guide/fractions.php | # Daniel I. Scully
## A Beginner's Guide to MathML
### Fractions
To write a fraction, or any thing which should be displayed in a similar way (e.g.: binomial coefficients), we can use the <mfrac> element.
1. <mfrac>
2. <mrow> <mi>x</mi><mo>+</mo><mn>2</mn> </mrow>
3. <mn>3</mn>
4. </mfrac>
$\frac{x+2}{3}$
The fraction is our first example of a feature which is strange to XML but common to MathML: the importance of order. Within an <mfrac> the first child is defined as the numerator and the second child the denominator. This also means that it must have exactly two children, no more, no less. When either the numerator or denominator are expressions in their own right, they must be grouped together in some other tag such as the <mrow> in the example above.
There are also four fraction-specific attributes which can be set to describe the layout of the fraction:
Attribute Description Allowed Values
linethickness Sets the thickness of the line which separates the numerator and the denominator
• number (a multiplier of the default thickness)
• thick
• medium (default)
• thin
numalign Sets the alignment of the numerator
• left
• center (default)
• right
denomalign Sets the alignment of the numerator
• left
• center (default)
• right
bevelled Determines whether the fraction is displayed with the separating line horizontal (false) or at an angle (true)
• true
• false (default)
Here are some examples of their use:
#### Example: Binomial coefficients
As we said earlier, <mfrac> is not just for fractions. By setting linethickness="0" we can use <mfrac> to display binomial coefficients:
1. <mfenced>
2. <mfrac linethickness="0">
3. <mn>2</mn>
4. <mn>3</mn>
5. </mfrac>
6. </mfenced>
$\left(\genfrac{}{}{0}{}{2}{3}\right)$
#### Example: Alignment
Using the 'denomalign' attribute, we can align the denominator in this expression to the right of the fraction.
1. <mfrac denomalign="right">
2. <mrow> <mi>x</mi><mo>+</mo><mn>2</mn> </mrow>
3. <mn>3</mn>
4. </mfrac>
$\frac{x+2}{\hfill 3}$
The same can be done with the numerator using 'numalign'.
#### Example: Bevelled fractions
When the 'bevelled' attribute is set to 'true', the fraction is displayed with a diagonal separator, instead of the horizontal one in the other examples above.
1. <mfrac bevelled="true">
2. <mrow> <mi>x</mi><mo>+</mo><mn>2</mn> </mrow>
3. <mn>3</mn>
4. </mfrac>
$x+2}{3}$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 4, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8943942785263062, "perplexity": 4335.2549433164795}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-13/segments/1490218186530.52/warc/CC-MAIN-20170322212946-00475-ip-10-233-31-227.ec2.internal.warc.gz"} |
https://docs.snowflake.com/en/sql-reference/external-functions-creating-gcp-external-function.html | # Step 4: Create the External Function for GCP in Snowflake¶
These instructions show how to create an external function database object in Snowflake. This database object stores information about the remote service, such as the parameters that the remote service accepts.
In this Topic:
## Create the External Function Database Object¶
You should be in a Snowflake web interface session.
1. Paste the command CREATE EXTERNAL FUNCTION. The command looks similar to the following:
create or replace external function <external_function_name>(<parameters>)
returns variant
api_integration = <api_integration_name>
as '<function_URL>' ;
2. Replace the <external_function_name> with a unique function name (e.g. echo).
3. Record the function name in the “External Function Name” field in the worksheet.
4. Replace the <parameters> with the names and SQL data types of the parameters, if any. For example: a integer, b varchar.
The parameters must correspond to the parameters expected by the remote service. The parameter names do not need to match, but the data types need to be compatible.
5. Record the parameter name and data types in the “External Function Name” field in the worksheet.
6. In the api_integration clause, replace the <api_integration_name> with the value in the “API Integration Name” field in the worksheet.
7. Replace the <function_URL> with the value in the “Gateway Base URL” field in the worksheet, followed by a slash (/) and the value in the “Path Suffix” field in the worksheet.
The URL should look similar to:
https://<gateway-base-url>/<path-suffix>
8. If you have not already done so, then execute the CREATE EXTERNAL FUNCTION command that you typed above.
9. You should now be able to call your external function to verify that it works correctly. For details, see Calling an External Function for GCP.
## Next Step¶
Snowflake strongly recommends setting a security policy on the Google Cloud API Gateway:
Step 5: Set the Security Policy for the Proxy Service (Google Cloud API Gateway) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.16552211344242096, "perplexity": 3566.1197927967005}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243992514.37/warc/CC-MAIN-20210513204127-20210513234127-00628.warc.gz"} |
http://aimsciences.org/article/doi/10.3934/proc.2009.2009.708 | # American Institute of Mathematical Sciences
2009, 2009(Special): 708-718. doi: 10.3934/proc.2009.2009.708
## Repelling soliton collisions in coupled Schrödinger equations with negative cross modulation
1 Department of Physics, Department of Mathematics, University of Louisiana at Lafayette, Lafayette, LA 70504-1010, United States 2 Department of Mathematics, University of Louisiana at Lafayette, Lafayette, LA 70504-1010, United States
Received August 2008 Revised July 2009 Published September 2009
The system of Coupled Nonlinear Schrödinger's Equations (CNLSE) is solved numerically by means of a conservative difference scheme. A new kind of repelling collision is discovered for negative values of the cross-modulation coupling parameter, $\alpha_2$. The results show that as the latter becomes increasingly negative, the behavior of the solitons during interaction change drastically. While for $\alpha_2 >0$, the solitons pass through each other, a negative threshold value $\alpha^*_2 < 0$ is found below which the solitons repell each other. This is a novel result for this kind of models and the conservation of momentum for the system of quasi-particles (QPs) is thoroughly investigated.
Citation: W. Josh Sonnier, C. I. Christov. Repelling soliton collisions in coupled Schrödinger equations with negative cross modulation. Conference Publications, 2009, 2009 (Special) : 708-718. doi: 10.3934/proc.2009.2009.708
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Impact Factor: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5857862830162048, "perplexity": 7205.092136935712}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376828318.79/warc/CC-MAIN-20181217042727-20181217064727-00320.warc.gz"} |
https://math.stackexchange.com/questions/799325/question-regarding-basic-probability | # Question regarding basic probability.
I'm looking for confirmation that what I for did this question is correct:
"If two people are randomly chosen from a group of eight women and six men, what is the probability that (a) both are women (b) one is a man and the other is a woman?"
a) The probability that both are women: $\frac{8}{14}\times\frac{7}{13}\approx.31$
b) The probability that one is a man and the other is a woman: $\frac{6}{14}\times\frac{8}{13}\approx.26$
• Why did you divide by $16$ in $b$ ? – Belgi May 17 '14 at 17:24
• oops, that was a typo. – Oscar Flores May 17 '14 at 17:25
Unfortunately, no. Your method works in part (a), but fails in part (b).
For a more generally workable method, we could proceed as follows. There are $\binom{14}2=91$ ways to pick $2$ people from a group of $14$. For part (a), there are $\binom82=28$ ways to pick two people from a group of $8$, so the answer is $\frac{28}{91}=\frac4{13},$ as you calculated.
For part (b), though, there are $8$ ways to choose one woman out of $8$ and $6$ ways to choose one man out of $6$, so there are $48$ ways to choose one man and one woman. Thus, the probability is $\frac{48}{91},$ instead.
Basically, what you found is the probability that a man was picked first and then a woman. However, for our purposes, we could have picked a woman first, instead, so we need to multiply this probability by $2$ to get the correct answer.
• Why do you call (a) coincidence? His method is what I'd have used, and it's correct. – JoeTaxpayer May 17 '14 at 19:42
• True. It's perfectly fine. – Cameron Buie May 17 '14 at 22:09
The first one is correct.
However, to see the problem with part $b$ try to answer this question: What is the probability that the first person is men and the second one is a woman ?
There are two possibilities of getting one of each gender:
First "man" then "woman" or first "woman" then "man" | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7228540182113647, "perplexity": 265.6888765335161}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514574532.44/warc/CC-MAIN-20190921145904-20190921171904-00236.warc.gz"} |
https://tohoku.pure.elsevier.com/en/publications/fragmentation-network-of-doubly-charged-methionine-interpretation | Fragmentation network of doubly charged methionine: Interpretation using graph theory
D. T. Ha, K. Yamazaki, Y. Wang, M. Alcamí, S. Maeda, H. Kono, F. Martín, E. Kukk
Research output: Contribution to journalArticlepeer-review
2 Citations (Scopus)
Abstract
The fragmentation of doubly charged gas-phase methionine (HO2CCH(NH2)CH2CH2SCH3) is systematically studied using the self-consistent charge density functional tight-binding molecular dynamics (MD) simulation method. We applied graph theory to analyze the large number of the calculated MD trajectories, which appears to be a highly effective and convenient means of extracting versatile information from the large data. The present theoretical results strongly concur with the earlier studied experimental ones. Essentially, the dication dissociates into acidic group CO2H and basic group C4NSH10. The former may carry a single or no charge and stays intact in most cases, whereas the latter may hold either a single or a double charge and tends to dissociate into smaller fragments. The decay of the basic group is observed to follow the Arrhenius law. The dissociation pathways to CO2H and C4NSH10 and subsequent fragmentations are also supported by ab initio calculations.
Original language English 094302 Journal of Chemical Physics 145 9 https://doi.org/10.1063/1.4962061 Published - 2016 Sep 7
ASJC Scopus subject areas
• Physics and Astronomy(all)
• Physical and Theoretical Chemistry
Fingerprint
Dive into the research topics of 'Fragmentation network of doubly charged methionine: Interpretation using graph theory'. Together they form a unique fingerprint. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9067205190658569, "perplexity": 5112.465273739741}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882572898.29/warc/CC-MAIN-20220817092402-20220817122402-00570.warc.gz"} |
https://dieklugeeule.com/wie-rechnen-sie-mit-2x-2-7x-3/ | # Wie rechnen Sie mit: 2x ^ 2 + 7x + 3 ?
#### Antworten:
(x+3)(2x+1)
#### Erläuterung:
"using the a-c method of factorising"
"the factors of "2xx3=6
"which sum to + 7 are + 6 and + 1"
"split the middle term using these factors"
rArr2x^2+6x+x+3larrcolor(blue)"factor by grouping"
=color(red)(2x)(x+3)color(red)(+1)(x+3)
"take out the common factor "(x+3)
=(x+3)(color(red)(2x+1))
rArr2x^2+7x+3=(x+3)(2x+1) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.41300150752067566, "perplexity": 10406.828409811977}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656103033925.2/warc/CC-MAIN-20220625004242-20220625034242-00274.warc.gz"} |
http://mathematica.stackexchange.com/questions/5519/solving-an-equation-and-finding-a-couple-of-results-given-that-they-are-integer/5520 | Solving an equation and finding a couple of results given that they are integer
My problem is to find all solutions to an equation with 2 variables between two values that define the range of my search. e.g., $(x+y-y²)/(1-y-x²)=0$ with solutions ${x,y} \in \mathbb{Z}$.
-
The following might be of use:
Reduce[x + y == y^2 && x^2 + y != 1, {x, y}, Integers]
To ease things, we consider the numerator and denominator separately. Here, we are asking Mathematica for conditions on integer x and y such that the numerator is zero, and the denominator isn't.
Solve[x + y == y^2 && x^2 + y != 1, {x, y}, Integers]
is useful as well.
If you need examples, you can use
FindInstance[x + y == y^2 && x^2 + y != 1, {x, y}, Integers, 10]
Change 10 to the number of examples you wish to generate.
-
thanks the tip of separating numerator and denominator is great ;) – sol May 14 '12 at 10:36
and for the FindInstance 10 that's what I needed! – sol May 14 '12 at 10:47
You can obtain all integer solutions with Reduce:
Reduce[(x + y - y^2)/(1 - y - x^2) == 0, {x, y}, Integers]
which gives
If you also want to restrict to solutions satisfying $x<15$ and $y<42$ then this works
Reduce[(x + y - y^2)/(1 - y - x^2) == 0 && x < 15 && x < 42, {x,y}, Integers]
-
ok thanks and if I want to condition it so that x and y are between [O,1] (how to condition the solving process?) – sol May 14 '12 at 10:29
you can do that in a way analogous to the second example I gave – acl May 14 '12 at 10:34
yep thanks Acl ^^ – sol May 14 '12 at 10:37 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6989167928695679, "perplexity": 976.9152954451849}, "config": {"markdown_headings": false, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-35/segments/1408500826259.53/warc/CC-MAIN-20140820021346-00232-ip-10-180-136-8.ec2.internal.warc.gz"} |
https://web2.0calc.com/questions/please-help-urgent_23 | +0
0
154
2
+128
A, B and C are three points on a plane such that AB = BC = 1 and CA = $$\sqrt3$$ Draw three circles whose diameters are $$\overline {AB}, \overline {BC}$$ and $$\overline {CA}$$ respectively. The area of the region included in all three circles (the grey region below) is $$\dfrac a b \pi +\dfrac {\sqrt c} d$$ in simplest form, so a, b, c, d are positive integers, a and b are relatively prime, and c is not divisible by the square of a prime. Enter the values of a, b, c, d in order, separating by commas.
THANKS SO MUCH
Feb 24, 2021
edited by Guest Feb 24, 2021
#1
0
The area is 3/2*pi + sqrt(3)/2, so the answer is (3,2,3,2).
Feb 24, 2021
#2
0
thanks,, but could you provide how you got the area to be that?
Guest Feb 24, 2021 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6679362654685974, "perplexity": 615.4233750194635}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-39/segments/1631780057524.58/warc/CC-MAIN-20210924110455-20210924140455-00221.warc.gz"} |
https://forum.allaboutcircuits.com/threads/scope-signal-adapter.62468/ | # scope signal adapter
#### automagp68
Joined Nov 13, 2011
81
Hi guys quick question
Im a first year EE student and i picked up this old Tektronix 2205 20 mhz scope from an estate sale
In the manual there is some procedure I'm suppose to go through (not named by the manual) for some adjustment purpose assuming that you have the originally included "signal adapters" I can't seem to find a picture of the "signal adapters" anyway and or what they do.
Can someone explain what a signal adapter is for (this scope) and its purpose. I can't seem to find any information on it online.
Also, i noticed that the probe impedance is 1MΩ
All the ones i have seen have been 50Ω
Not sure how this effects the probes. I have about 5 different probes it came with.
Any ideas would be greatly helpful as I'm trying to learn this device and also test its current accuracy.
Thanks
#### SgtWookie
Joined Jul 17, 2007
22,220
Im a first year EE student and i picked up this old Tektronix 2205 20 mhz scope from an estate sale
Hard to go wrong with a Tektronix.
In the manual there is some procedure I'm suppose to go through (not named by the manual) for some adjustment purpose assuming that you have the originally included "signal adapters" I can't seem to find a picture of the "signal adapters" anyway and or what they do.
Can someone explain what a signal adapter is for (this scope) and its purpose. I can't seem to find any information on it online.
Tek 2205 Service Manual: http://www.danielvg.be/2205_SM.pdf
From page 2-7:
CONNECTING SIGNALS
The signal adapter supplied with the instrument is
usually the most convenient way to connect a signal
to the 2205. These signal adapters are shielded to
prevent pickup of electromagnetic interference.
When connected to the 2205 input, a signal adapter
presents 1M Ohm and about 100 pF impedance to the
circuit under test. If this capacitance is disruptive to
the circuit being tested, use the optional 10X probe
Basically, they are talking about the entire scope probe, from the bayonet base to the tip of the probe.
Also, i noticed that the probe impedance is 1MΩ
All the ones i have seen have been 50Ω
Not sure how this effects the probes. I have about 5 different probes it came with.
The impedance is 50 Ohms at the input to the O-scope, and a 1x probe is 1 MEG at the tip; a 10x probe is 10MEG, a 100x probe is 100MEG. You can frequently find switchable probes that will go 1x-10x or 1x-10x-100x.
Don't forget to adjust the compensation for your probes. That procedure is documented on page 2-9. The PROBE ADJ output is located on the bottom of the front panel, just to the left of EXT INPUT (see page 2-4).
#### automagp68
Joined Nov 13, 2011
81
Hey Sgt!
thanks for all the great info and that link. That is great. I could not find that thing anywhere. And that seems more helpful then the one i have.
So the signal adapter is part of the probe? Am i understanding that correctly.
Also, the other thing i may have messed up mentioned is that the scope actually says 1MΩ input impedance.
Like my old leader scope says 50Ω
Im not exactly sure how that effects measurments.
#### SgtWookie
Joined Jul 17, 2007
22,220
Thanks for all the great info and that link. That is great. I could not find that thing anywhere. And that seems more helpful then the one i have.
That is the service manual. It is a really, really good thing to have. After you gain some experience with building things, and save up some \$, you should consider replacing all of the electrolytic capacitors in your O-scope. It's a good 'scope, but it's getting old - and electrolytic capacitors are usually the most troublesome item in older test equipment. The best thing to do is to replace them all, so you will get another 15-20 years of service out of it.
If you fail to replace the capacitors before they start dying, you risk damage to the adjacent components when the caps start failing - they frequently take out a number of components when they go. You really don't want that to happen.
So the signal adapter is part of the probe? Am i understanding that correctly.
It's informally called an oscilloscope probe, or o'scope probe. "Signal adapter" was more proper, but antiquated - if you ask someone for a signal adapter, they will probably look at you as if you had two heads. If you say "O'scope probe", or "oscilloscope probe" they will know that you are talking about this:
Also, the other thing i may have messed up mentioned is that the scope actually says 1MΩ input impedance.
Like my old leader scope says 50Ω
Im not exactly sure how that effects measurments.
1MEG can certainly load a signal. 10MEG will load the signal 1/10th as much. You use x1 and x10 at different times. It's getting late to describe when you'd use each mode, but you'll pick that up as you use it.
The Navy NEETS module 16 has an intro to oscilloscopes and various other pieces of test equipment. It's dated due to the equipment in the document, but you will have many of the same controls on your O'scope:
http://www.phy.davidson.edu/instrumentation/NEETS.htm
You should go through the rest of the modules when you have time. I went through a predecessor course back in the 70's.
#### crutschow
Joined Mar 14, 2008
25,631
..............
The impedance is 50 Ohms at the input to the O-scope, and a 1x probe is 1 MEG at the tip; a 10x probe is 10MEG, a 100x probe is 100MEG. You can frequently find switchable probes that will go 1x-10x or 1x-10x-100x.
............
Most old oscilloscopes have a 1meg input. Obviously that is required if a 1x probe is 1meg and a 10x probe is to have a 10meg impedance.
Many newer scopes have a switchable 50Ω/1megΩ input impedance. The 50Ω impedance is used when you want a matched termination for 50Ω cables and source. The 1megΩ input is used for 1x and 10x probes. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4614104926586151, "perplexity": 2145.4973912264627}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141164142.1/warc/CC-MAIN-20201123182720-20201123212720-00353.warc.gz"} |
https://www.physicsforums.com/threads/induced-current.117159/ | # Homework Help: Induced current
1. Apr 10, 2006
### Punchlinegirl
An aluminum ring of radius 5 cm and resistance 0.003 ohms is placed around the center of a long air-core solenoid with 1000 turns per meter and a smaller radius of 3 cm. If the current in the solenoid is increasing at a constant rate of 270 A/s, what is the induced current in the ring?
B= $$\mu*n*I$$
change in B/change in time = $$\mu$$ n *change in current/change in time
= $$4 \pi e-7)(1000)(270)$$ = .339
then change in flux/change in time= A*change in B/change in t
A= $$\pi*r^2$$
So A= (.03)^2 *3.14
then multiply that by .339 to get 9.58 e -4.
Then I divided this by 3 e -4 to get the current and found that it was 3.19..
Last edited: Apr 10, 2006
2. Apr 10, 2006
### Hootenanny
Staff Emeritus
I think the question wants you to use Faraday's law. Incidently, thats how I would go about it.
-Hoot
3. Apr 10, 2006
### Punchlinegirl
So if I use Faraday's Law, would I do
change in flux= B*cos (theta)A
Where B= $$\mu$$ I* n
and would A be the big area minus the small? $$\pi$$ (.05^2)-(.03^2)? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8981838822364807, "perplexity": 3774.443397763871}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376828018.77/warc/CC-MAIN-20181216234902-20181217020902-00459.warc.gz"} |
http://mathhelpforum.com/calculus/61788-convergence-series.html | # Thread: Convergence of a series
1. ## Convergence of a series
Consider
$f (x) = \sum_{n=1} ^ {\infty} 1/{n(1 + nx^2)}$
(a) For what values of $x$ does the series converge?
(b) On what intervals of the form $(a,b)$ does the series converge uniformly?
(c) On what intervals of the form $(a,b)$ does the series fail to converge uniformly?
(d) Is $f$ continuous at all points where the series converges?
I would appreciate any help. Meanwhile I am trying to do the question by myself and would let everyone know of any breakthroughs.
Thanks
2. Ok, I have done part (a). Using the limit comparison test with the series $1/n^2$ which we know converges we compute the limit to be $x^2$ which in reals is always positive provided it's non zero. If $x = 0$ well then we get the harmonic series which everyone knows diverges.
3. Originally Posted by davidmccormick
Consider
$f (x) = \sum_{n=1} ^ {\infty} 1/{n(1 + nx^2)}$
(a) For what values of $x$ does the series converge?
(b) On what intervals of the form $(a,b)$ does the series converge uniformly?
(c) On what intervals of the form $(a,b)$ does the series fail to converge uniformly?
(d) Is $f$ continuous at all points where the series converges?
I would appreciate any help. Meanwhile I am trying to do the question by myself and would let everyone know of any breakthroughs.
Thanks
Is this $\sum_{n=1}^{\infty}\frac{1+nx^2}{n}$ or $\sum_{n=1}^{\infty}\frac{1}{n(1+nx^2)}$. I think it is the latter.
a) All except 0 consider that $\lim_{n\to\infty}\frac{\frac{1}{n(1+nx^2)}}{\frac{ 1}{n(n+1)}}=x^2$
b) Use the Weirstrass M-test. For which thing to compare it to consider what interval you may definitely say that $\left|\frac{1}{n(1+nx^2)}\right|\leqslant\frac{1}{ n(n+1)}$ and then consider the other interval serperately
c) This should be found during b0
d) Use the fact that if $\sum_{n=0}^{\infty}f_n(x)$ is uniformly convergent on $[a,b]$ and $f_n(x)\in\mathcal{C}$ than so is $f(x)=\sum_{n=0}^{\infty}f_n(x)$
4. It is indeed the latter. Thank you for your help.
5. Parts (a) and (d) are fine. For part (b) I managed to show that the series converges uniformly on the intervals $(-{\infty},-1]$ and $[1, {\infty})$ but have no idea how to show whether or not uniform convergence applies to (-1,1) interval. Can you explain a little more please? thanks.
6. Originally Posted by davidmccormick
Parts (a) and (d) are fine. For part (b) I managed to show that the series converges uniformly on the intervals $(-{\infty},-1]$ and $[1, {\infty})$ but have no idea how to show whether or not uniform convergence applies to (-1,1) interval. Can you explain a little more please? thanks.
Try considering the intervals $\left(a\ne{0},1\right)$ and $\left(-1,a\ne{0}\right))$ and that $\left|\frac{1}{n
(1+nx^2)}\right|\leqslant\frac{1}{n(1+\min_{(a\ne{ 0},1)}\left\{x^2\right\}n)}$
and use the Limit comparison test on the right hand series.
7. What series can we compare the series on the right hand side of the inequality to (in the limit comparison test)? Also, if we can show this it means that our original series is uniform convergent everywhere except for
$x = 0$, and so the answer to part (c) is any interval which doesn't contain 0, right?
8. Originally Posted by davidmccormick
What series can we compare the series on the right hand side of the inequality to (in the limit comparison test)?
If $0 then $0\leqslant\frac1{n(1+nx^2)}\leqslant\frac1{n(1+na^ 2)}\leqslant \frac1{n^2a^2}$ and you can use the M-test. Similarly on the interval $-1\leqslant x\leqslant -a$.
Originally Posted by davidmccormick
so the answer to part (c) is any interval which doesn't contain 0, right?
Any closed interval which doesn't contain 0.
9. thanks very much for your help. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 32, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9617400765419006, "perplexity": 201.39131875007507}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2013-48/segments/1386163049615/warc/CC-MAIN-20131204131729-00021-ip-10-33-133-15.ec2.internal.warc.gz"} |
https://www.aimsciences.org/article/doi/10.3934/cpaa.2009.8.1159 | # American Institute of Mathematical Sciences
July 2009, 8(4): 1159-1201. doi: 10.3934/cpaa.2009.8.1159
## On a class of hypoelliptic operators with unbounded coefficients in $R^N$
1 Technische Universität Darmstadt, Fachbereich Mathematik, AG Analysis, Schloßgartenstraße 7, D-64289, Darmstadt, Germany 2 Dipartimento di Matematica, Universitá degli Studi di Parma, Viale G. Usberti 85/A, 43100 Parma
Received June 2008 Revised December 2008 Published March 2009
We consider second order linear partial differential operators $A$ on $R^N$ which are not assumed to be uniformly elliptic and whose coefficients in the second order part may grow quadratically, while the drift part has essentially linear growth. Instead of uniform ellipticity, we require a much weaker hypothesis of uniform hypoellipticity, which in an equivalent formulation connects the behaviour of the diffusion and the drift coefficients, by requiring that a Kalman-type condition is satisfied for them. By refining Bernstein's method we prove the existence of a semigroup {$T(t)$} of bounded linear operators (in the space of bounded and continuous functions) associated to the operator $A$. We also show uniform estimates for the spatial derivatives of the semigroup {$T(t)$} in (an)isotropic spaces of (Hölder-) continuous functions. As a consequence, we obtain Hölder estimates for the solutions of some elliptic and parabolic problems associated to the operator $A$.
Citation: Bálint Farkas, Luca Lorenzi. On a class of hypoelliptic operators with unbounded coefficients in $R^N$. Communications on Pure & Applied Analysis, 2009, 8 (4) : 1159-1201. doi: 10.3934/cpaa.2009.8.1159
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2019 Impact Factor: 1.105 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6617730855941772, "perplexity": 3452.96224546766}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-45/segments/1603107869785.9/warc/CC-MAIN-20201020021700-20201020051700-00383.warc.gz"} |
https://www.rdocumentation.org/packages/spdep/versions/0.6-9/topics/errorsarlm | # errorsarlm
0th
Percentile
##### Spatial simultaneous autoregressive error model estimation
Maximum likelihood estimation of spatial simultaneous autoregressive error models of the form:
$$y = X \beta + u, u = \lambda W u + \varepsilon$$
where $lambda$ is found by optimize() first, and $beta$ and other parameters by generalized least squares subsequently. With one of the sparse matrix methods, larger numbers of observations can be handled, but the interval= argument may need be set when the weights are not row-standardised. When etype is “emixed”, a so-called spatial Durbin error model is fitted, while lmSLX fits an lm model augmented with the spatially lagged RHS variables, including the lagged intercept when the spatial weights are not row-standardised. create_WX creates spatially lagged RHS variables, and is exposed for use in model fitting functions.
Keywords
spatial
##### Usage
errorsarlm(formula, data=list(), listw, na.action, weights=NULL, etype="error", method="eigen", quiet=NULL, zero.policy=NULL, interval = NULL, tol.solve=1.0e-10, trs=NULL, control=list())
lmSLX(formula, data = list(), listw, na.action, weights=NULL, zero.policy=NULL)
create_WX(x, listw, zero.policy=NULL, prefix="")
##### Arguments
formula
a symbolic description of the model to be fit. The details of model specification are given for lm()
data
an optional data frame containing the variables in the model. By default the variables are taken from the environment which the function is called.
listw
a listw object created for example by nb2listw
na.action
a function (default options("na.action")), can also be na.omit or na.exclude with consequences for residuals and fitted values - in these cases the weights list will be subsetted to remove NAs in the data. It may be necessary to set zero.policy to TRUE because this subsetting may create no-neighbour observations. Note that only weights lists created without using the glist argument to nb2listw may be subsetted.
weights
an optional vector of weights to be used in the fitting process. Non-NULL weights can be used to indicate that different observations have different variances (with the values in weights being inversely proportional to the variances); or equivalently, when the elements of weights are positive integers w_i, that each response y_i is the mean of w_i unit-weight observations (including the case that there are w_i observations equal to y_i and the data have been summarized) - lm
etype
default "error", may be set to "emixed" to include the spatially lagged independent variables added to X; when "emixed", the lagged intercept is dropped for spatial weights style "W", that is row-standardised weights, but otherwise included
method
"eigen" (default) - the Jacobian is computed as the product of (1 - rho*eigenvalue) using eigenw, and "spam" or "Matrix_J" for strictly symmetric weights lists of styles "B" and "C", or made symmetric by similarity (Ord, 1975, Appendix C) if possible for styles "W" and "S", using code from the spam package or Matrix package to calculate the determinant; “Matrix” and “spam_update” provide updating Cholesky decomposition methods; "LU" provides an alternative sparse matrix decomposition approach. In addition, there are "Chebyshev" and Monte Carlo "MC" approximate log-determinant methods; the Smirnov/Anselin (2009) trace approximation is available as "moments". Three methods: "SE_classic", "SE_whichMin", and "SE_interp" are provided experimentally, the first to attempt to emulate the behaviour of Spatial Econometrics toolbox ML fitting functions. All use grids of log determinant values, and the latter two attempt to ameliorate some features of "SE_classic".
quiet
default NULL, use !verbose global option value; if FALSE, reports function values during optimization.
zero.policy
default NULL, use global option value; if TRUE assign zero to the lagged value of zones without neighbours, if FALSE assign NA - causing errorsarlm() to terminate with an error
interval
default is NULL, search interval for autoregressive parameter
tol.solve
the tolerance for detecting linear dependencies in the columns of matrices to be inverted - passed to solve() (default=1.0e-10). This may be used if necessary to extract coefficient standard errors (for instance lowering to 1e-12), but errors in solve() may constitute indications of poorly scaled variables: if the variables have scales differing much from the autoregressive coefficient, the values in this matrix may be very different in scale, and inverting such a matrix is analytically possible by definition, but numerically unstable; rescaling the RHS variables alleviates this better than setting tol.solve to a very small value
trs
default NULL, if given, a vector of powered spatial weights matrix traces output by trW; when given, insert the asymptotic analytical values into the numerical Hessian instead of the approximated values; may be used to get around some problems raised when the numerical Hessian is poorly conditioned, generating NaNs in subsequent operations. When using the numerical Hessian to get the standard error of lambda, it is very strongly advised that trs be given, as the parts of fdHess corresponding to the regression coefficients are badly approximated, affecting the standard error of lambda; the coefficient correlation matrix is unusable
control
list of extra control arguments - see section below
x
model matrix to be lagged
prefix
default empty string, may be “lag” in some cases
##### Details
The asymptotic standard error of $lambda$ is only computed when method=eigen, because the full matrix operations involved would be costly for large n typically associated with the choice of method="spam" or "Matrix". The same applies to the coefficient covariance matrix. Taken as the asymptotic matrix from the literature, it is typically badly scaled, being block-diagonal, and with the elements involving $lambda$ being very small, while other parts of the matrix can be very large (often many orders of magnitude in difference). It often happens that the tol.solve argument needs to be set to a smaller value than the default, or the RHS variables can be centred or reduced in range.
Note that the fitted() function for the output object assumes that the response variable may be reconstructed as the sum of the trend, the signal, and the noise (residuals). Since the values of the response variable are known, their spatial lags are used to calculate signal components (Cressie 1993, p. 564). This differs from other software, including GeoDa, which does not use knowledge of the response variable in making predictions for the fitting data.
##### Value
A list object of class sarlmThe internal sar.error.* functions return the value of the log likelihood function at $lambda$.The lmSLX function returns an “lm” object with a “mixedImps” list of three impact matrixes (impacts and standard errors) for direct, indirect and total impacts; total impacts calculated using gmodels::estimable.
##### References
Cliff, A. D., Ord, J. K. 1981 Spatial processes, Pion; Ord, J. K. 1975 Estimation methods for models of spatial interaction, Journal of the American Statistical Association, 70, 120-126; Anselin, L. 1988 Spatial econometrics: methods and models. (Dordrecht: Kluwer); Anselin, L. 1995 SpaceStat, a software program for the analysis of spatial data, version 1.80. Regional Research Institute, West Virginia University, Morgantown, WV; Anselin L, Bera AK (1998) Spatial dependence in linear regression models with an introduction to spatial econometrics. In: Ullah A, Giles DEA (eds) Handbook of applied economic statistics. Marcel Dekker, New York, pp. 237-289; Cressie, N. A. C. 1993 Statistics for spatial data, Wiley, New York; LeSage J and RK Pace (2009) Introduction to Spatial Econometrics. CRC Press, Boca Raton.
Roger Bivand, Gianfranco Piras (2015). Comparing Implementations of Estimation Methods for Spatial Econometrics. Journal of Statistical Software, 63(18), 1-36. http://www.jstatsoft.org/v63/i18/.
Bivand, R. S., Hauke, J., and Kossowski, T. (2013). Computing the Jacobian in Gaussian spatial autoregressive models: An illustrated comparison of available methods. Geographical Analysis, 45(2), 150-179.
lm, lagsarlm, similar.listw, summary.sarlm, predict.sarlm, residuals.sarlm, do_ldet, estimable
• errorsarlm
• lmSLX
• create_WX
##### Examples
data(oldcol)
lw <- nb2listw(COL.nb, style="W")
COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="eigen", quiet=FALSE)
summary(COL.errW.eig, correlation=TRUE)
ev <- eigenw(similar.listw(lw))
COL.errW.eig_ev <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="eigen", control=list(pre_eig=ev))
all.equal(coefficients(COL.errW.eig), coefficients(COL.errW.eig_ev))
COL.errB.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
nb2listw(COL.nb, style="B"), method="eigen", quiet=FALSE)
summary(COL.errB.eig, correlation=TRUE)
W <- as(nb2listw(COL.nb), "CsparseMatrix")
trMatc <- trW(W, type="mult")
COL.errW.M <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix", quiet=FALSE, trs=trMatc)
summary(COL.errW.M, correlation=TRUE)
COL.SDEM.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="eigen", etype="emixed")
summary(COL.SDEM.eig, correlation=TRUE)
summary(impacts(COL.SDEM.eig))
COL.SLX <- lmSLX(CRIME ~ INC + HOVAL, data=COL.OLD, listw=lw)
summary(COL.SLX)
summary(impacts(COL.SLX))
COL.SLX <- lmSLX(CRIME ~ INC + HOVAL + I(HOVAL^2), data=COL.OLD, listw=lw)
summary(COL.SLX)
COL.SLX <- lmSLX(CRIME ~ INC, data=COL.OLD, listw=lw)
crds <- cbind(COL.OLD$X, COL.OLD$Y)
mdist <- sqrt(sum(diff(apply(crds, 2, range))^2))
dnb <- dnearneigh(crds, 0, mdist)
dists <- nbdists(dnb, crds)
f <- function(x, form, data, dnb, dists, verbose) {
glst <- lapply(dists, function(d) 1/(d^x))
lw <- nb2listw(dnb, glist=glst, style="B")
res <- logLik(lmSLX(form=form, data=data, listw=lw))
if (verbose) cat("power:", x, "logLik:", res, "\n")
res
}
opt <- optimize(f, interval=c(0.1, 4), form=CRIME ~ INC + HOVAL,
data=COL.OLD, dnb=dnb, dists=dists, verbose=TRUE, maximum=TRUE)
glst <- lapply(dists, function(d) 1/(d^opt$maximum)) lw <- nb2listw(dnb, glist=glst, style="B") SLX <- lmSLX(CRIME ~ INC + HOVAL, data=COL.OLD, listw=lw) summary(SLX) summary(impacts(SLX)) NA.COL.OLD <- COL.OLD NA.COL.OLD$CRIME[20:25] <- NA
COL.err.NA <- errorsarlm(CRIME ~ INC + HOVAL, data=NA.COL.OLD,
nb2listw(COL.nb), na.action=na.exclude)
COL.err.NA\$na.action
COL.err.NA
resid(COL.err.NA)
lw <- nb2listw(COL.nb, style="W")
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="eigen"))
ocoef <- coefficients(COL.errW.eig)
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="eigen", control=list(LAPACK=FALSE)))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="eigen", control=list(compiled_sse=TRUE)))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix_J", control=list(super=TRUE)))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix_J", control=list(super=FALSE)))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix_J", control=list(super=as.logical(NA))))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix", control=list(super=TRUE)))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix", control=list(super=FALSE)))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="Matrix", control=list(super=as.logical(NA))))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="spam", control=list(spamPivot="MMD")))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="spam", control=list(spamPivot="RCM")))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="spam_update", control=list(spamPivot="MMD")))
all.equal(ocoef, coefficients(COL.errW.eig))
system.time(COL.errW.eig <- errorsarlm(CRIME ~ INC + HOVAL, data=COL.OLD,
lw, method="spam_update", control=list(spamPivot="RCM")))
all.equal(ocoef, coefficients(COL.errW.eig))
Documentation reproduced from package spdep, version 0.6-9, License: GPL (>= 2)
### Community examples
Looks like there are no examples yet. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4377802312374115, "perplexity": 12888.087341407136}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590347413406.70/warc/CC-MAIN-20200531120339-20200531150339-00238.warc.gz"} |
https://www.arxiv-vanity.com/papers/astro-ph/0008041/ | # [
[
###### Abstract
A combined sample of 79 high and low redshift supernovae Ia (SNe) is used to set constraints on the degree of anisotropy in the Universe out to . First we derive the global most probable values of matter density , the cosmological constant , and the Hubble constant , and find them to be consistent with the published results from the two data sets of Riess et al. 1998 (R98) and Perlmutter et al. 1999 (P99). We then examine the Hubble diagram (HD, i.e., the luminosity-redshift relation) in different directions on the sky by utilising spherical harmonic expansion. In particular, via the analysis of the dipole anisotropy, we divide the sky into the two hemispheres that yield the most discrepant of the three cosmological parameters, and the scatter in each case. The most discrepant values roughly move along the locus (cf. P99), but by no more than along this line. For a perfect FRW universe, Monte Carlo realizations that mimic the current set of SNe yield values higher than the measured in of the cases. We discuss implications for the validity of the Cosmological Principle, and possible calibration problems in the SNe data sets.
c
]Constraints on Cosmological Anisotropy out to from Supernovae Ia Kolatt & Lahav ] Tsafrir S. Kolatt and Ofer Lahav
Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
Institute of Astronomy, Madingley Rd., CB3 0HA, Cambridge, UK
osmology: miscellaneous – cosmology: observations – cosmology: theory – supernovae:general
## 1 Introduction
The validity of the Cosmological Principle and the isotropy it implies gained much credibility in recent years. The small fluctuations in the CMB ( on angular scale ) provide the strongest evidence that the universe can be well approximated by the FRW metric on scales larger than (e.g., Peebles 1993; Wu, Lahav, & Rees 1999)
On smaller scales () bulk flows of the order indicate that this isotropy breaks down. This is also manifested by significant correlation functions of galaxies and clusters on large scales, and structures like the Supergalactic Plane and the Great Attractor. The transition scale to isotropy and homogeneity is still poorly known, and so is the convergence of the acceleration vector of the Local Group with respect to the CMB. It is therefore important to quantify the degree of homogeneity and isotropy as function of scale. Traditionally this was done by searching for anisotropy in the distribution of radio sources and background radiations [Nan & Cai (1996), Evans (1992), Webster (Webster)]. Several new methods have been suggested to test isotropy and homogeneity on redshift scales of , such as measurements of in situ CMB temperature [Songaila et al. (1994)], the derivation of an independent rest frame from multiple image lens systems [Kochanek et al. (1996)], and Faraday rotation signature due to anisotropic magnetic field [Kronberg (1976), Vallée (1990), Nodland & Ralston (1997)].
The recent use of SNe as distance indicators [Phillips (1993), Perlmutter et al. (1995), Riess et al. (1996)] opened a new opportunity for accurate measurements of anisotropy on cosmological scales that previously have not been accessible. So far the SNe have been used in order to constrain the Hubble constant from a nearby sample and combinations of the matter density and the cosmological constant utilizing SNe at moderate () and high () redshifts. In the future, SNe samples over a wider redshift range will provide separate estimates for the two parameters. It is important to establish the ‘universality’ of the measurements of cosmological parameters from SN, as they are commonly used in joint analysis with other probes such as the CMB, cluster abundance and peculiar velocities [Efstathiou (1999), Efstathiou et al. (1999), Bridle et al. (1999), Bridle et al. (Bridle et al.), Tegmark (1999)].
Assuming a FRW cosmology, a forth measure can be deduced from the ‘Hubble diagram’ (HD; i.e., the luminosity – redshift relation), the measure for the best fit model. For a perfect distance indicator this measure indicates deviations of the local potential (i.e., at the location of the SN) from a pure FRW geometry. However, in the real universe the deviations can also be due to other sources:
• Intrinsic (astrophysical) scatter in the SN luminosity-light curve relation.
• Scatter due to the location of the SN within the host galaxy & the galaxy type.
• Scatter due to dust absorption in the host galaxy, in the intergalactic medium and in our Galaxy.
• Gravitational lensing along the l.o.s. to the SN (e.g., an overdensity along the l.o.s. will enhance the apparent luminosity of a SN).
Here we explicitly assume that there is no evolution with redshift in the luminosity-light curve relation. Fortunately, most of the abovementioned effects are on the scale of the host galaxy, so with large enough sample they would be averaged out in the calculation of large scale anisotropies. On the other hand, one should worry about ‘anisotropies’ which are simply due to poor matching of different data sets that sample different portions of the sky, or large angular effects due to Galactic extinction.
We also note that some of these effects above might be correlated with other measurements, e.g. if the scatter detected in SN Hubble diagram is affected by fluctuations in the potential, then it would be correlated with Integrated SW (or Rees-Schiama) effect in the CMB fluctuations.
The outline of this paper is as follows, in §2 we present the unified data set we will be using for the isotropy analysis. The results for cosmological parameters from the entire sample are presented in §3, the anisotropy measurement is discussed in §4, and put in a probabilistic context in §5. We conclude our results in §6.
## 2 The Unified Data set
An ideal data set of SNe for the goals we have put forward in the introduction would be a whole-sky homogeneous coverage at various redshifts of SNe. Since such an optimal set does not exist, the closest data set would be the amalgamation of the two existing, published data sets.
We unify the samples of the Supernova Cosmology Project (SCP) [Perlmutter et al. (1999)] and that of the High-z Supernova search team (HZS) [Riess et al. (1998)]. These include also the data from low redshift of the Calán-Tololo survey [Hamuy et al. (1996)]. The two groups have different strategy and different nomenclature for the minimization problem by which the cosmological parameters are derived. We have brought the SCP data to comply with the language of the HZS team
For each SNe we list its (i) in the CMB frame, (ii) the distance modulus , (iii) errors for these two quantities, (iv) Galactic and . For the SCP data the fiducial magnitude, (cf. P99), is obtained by comparison of the 18 overlapping low redshift SNe as analysed by the two groups, and equating the distance modulus of R98 (table 10) to of P99 (table 2). This procedure is repeated twice, since Riess et al. provide two ways to calculate the distance moduli, “Multi Light Curve Shapes” (LCS) and “Template”. Errors are taken from the tables and a least square minimization is performed in order to obtain the two best fit values of of P99 (and to recover the Hubble constant dependence they omitted in their calculation). The two values are with of 0.952 and 0.763 for the LCS method and the TEMPLATE method respectively. The value of is degenerated with , so different calibrations in the two samples get “absorbed” in the value for . The unified sample consists of 79 SNe altogether, after the exclusion of 6 SNe from P99 (taking their “model C” version) and including the snap-shot survey from R98 along with 1997ck. Figure 1 shows the SNe distribution in Galactic coordinates.
The sky coverage is clearly inhomogeneous: the SNe deficiency near the Galactic plane is evident and the clustering of a few of the observed SNe due to the detection procedure is clear.
## 3 Cosmological parameters from the unified sample
We follow the statistical analysis as described in R98 and obtain best values for and probability contours in the () plane after integration (i.e. marginalization) over all values and taking into account only physical regions in that plane.
P99 include the error due to redshift measurements and peculiar velocities in their magnitude errors, for R98 we followed their procedure, set km s for SNe of and km s for SNe with , and translated to the distance modulus, , units according to the assumed cosmological model in the likelihood function. Figure 2 show the results of the likelihood analysis. The maxima of the likelihood functions are obtained for () values of () and () for the LCS and TEMPLATE method respectively. The contour lines correspond to the , , and confidence levels.
## 4 Anisotropy measurement
The natural expansion for anisotropy detection is in spherical harmonics. The current data are too sparse to allow analysis in redshift shells.
We expand the four two-dimensional parameter ‘fields’ (for , , , and ) in spherical harmonics. If the isotropy assumption is valid we expect deviations from the average value to be due to noise, and the angular power spectrum should likewise reflect it. This is unless foreground effects alter the signal significantly.
The operational way to calculate the expansion coefficients is as follows.
• Build a random distribution of points (“mask”) on the sphere.
• Construct the four residual fields about the global mean, i.e., , where is , , , or .
• Expand the values as obtained at each grid point in Spherical Harmonics up to , i.e.
δF(θ,ϕ)=l=lmax∑l=0m=+l∑m=−lamlYml. (1)
In order to include more than SNe in each smoothing bin (at least two-parameter fit) we obtain , however the SNe are not distributed uniformly (cf. Fig. 1) and thus a minimum angular resolution of is imposed. That means that for a whole sky coverage the highest significant multipole, , is . There are, though regions that are more densely covered by SNe data and therefore higher multipoles can be assessed as well but at a lower signal-to-noise level.
In order to account for the Poisson noise contribution (and thus to the angular power spectrum in quadrature), we run a set of random “masks” and repeat the calculation each time. For each set of the power spectrum coefficients, are computed.
The angular power spectrum of the is an order of magnitude and more smaller than the noise level (), in both methods. Figure 3 shows the angular power spectrum, , for the other three fields as calculated from 50 runs with different random mask points. The straight weaker lines show the noise level in each field. The fields in both methods show signals that exceed the noise level for the dipole () and the quadrupole (). Two factors contribute to the noise level, the discrete number of SNe, and the scatter in the luminosity — redshift relation. The former is common to both methods (LCS and TEMPLATE) and therefore the order of magnitude higher noise level for the fields in the LCS method must be due to the latter. The TEMPLATE method seems to provide smaller errors and a better match between the two data sets, as indicated by the lower level of the fiducial magnitude calibration (cf. §2). The angular power spectrum is similar in shape and magnitude in both methods, and lies an order of magnitude to a factor above its noise level. This may indicate there exists a true dipole (or quadrupole) in this field. From the first multipole of angular power spectrum alone, one cannot deduce what is the dipole direction. We therefore turn to look for the direction by other means.
We search for largest dipole in , , , and . This has been done in two ways : an actual search over the sky, dividing the SN population in between two hemispheres, and equivalently, by solving a maximization problem of the dipole term with respect to using the computed coefficients. Both methods yield similar results. We then calculate the confidence regions for each hemisphere separately, and look for statistical consistency (overlapping contours). Each test can be applied to each one of the four parameters.
Figure 4 verify the fact that the current SNe data best constrain a linear combination of the cosmological parameters , . In all four panels the likelihood maxima move along the line (P99) , sometimes with a large distance between the two maxima for the two disjoint hemispheres (quoted on the plots). In three cases the contour levels overlap significantly (see next section for quantitative evaluation). In the case of the dipole, using the LCS method, there is no overlap between the confidence levels of the two hemispheres. The discrepancy stems from the very assymetric distribution of SNe between the two hemispheres (59 on one versus 20 on the other) and only one SN (1995at) with in the 20 SNe sample. A small error in the distance measurement of this SN, or a systematic deviation of it from the average LCS relation may cause such a discrepancy as we demonstrate in the next section. Elimination of this SN yields a dipole which points away from the original direction, reduced value of , and almost full inclusion of the confidence contour for the larger sample ( SNe) within the confidence level of the remaining SNe.
Note that a different “mixture” of redshift distribution to different directions may cause some directions to become more sensitive to one parameter. E.g, SNe at are mostly sensitive to the combination, as opposed to higher weight on as redshift increases (). Figure 1 includes the dipole directions (positive) of in both methods. We observe no coincidence with any Galactic or CMB direction, moreover not all dipoles point to the same direction.
The dipole of the field points in both methods toward with and largest difference of for the LCS (TEMPLATE) method. This dipole direction is suspiciously close to the Galactic plane.
One worry is that the detected signal is due to the (mis)match between the two data sets. We therefore repeated the computation for each data set separately and verified that though the noise level increases, the results as drawn from each one of the data sets are consistent with the results from the unified set both in magnitude and direction.
## 5 Degree of anisotropy
The results of the last section, regarding the spherical harmonic expansion and the various dipole magnitudes, should now be put in an expected distribution in order to draw conclusions about the degree of anisotropy.
The hypothesis we are trying to address is that the SN data do not falsify the FRW geometry as a reliable description of the Universe. This strategy is more efficient than addressing specific anisotropic cosmological models [Célérier (2000a), Célérier (2000b)]. We therefore compute the probability distribution of the dipole magnitudes within a FRW universe and confront it with the values obtained for the real Universe.
A simple two dimensional Kolmogorov-Smirnov test to falsify the hypothesis that the two contour maps come from the same underlying distribution of cosmological parameters is inadequate here. Since we have used the maximum discrepant values in order to obtain the dipole, the two sub-samples are not randomly selected and therefore can not be confronted in a KS test.
The probability distribution depends on the actual cosmological values and to a lesser extent on the power spectrum (via the scatter due to potential fluctuations). For a self consistency check, the underlying cosmology is taken to be the ”best fit” cosmological model (§3), which we then sample by Monte-Carlo simulations.
To mimic accurately the SN sample, we use the same angular locations and redshift values as of the observed sample. Luminosity distances, magnitude scatter and peculiar velocities are drawn from Gaussian distributions with the appropriate observed standard deviation.
The dipole analysis is repeated for mock catalogs of the SN and the maximal dipole magnitude is calculated to obtain its distribution for the current sampled SNe.
Table 1 shows the rejection levels of the hypothesis that the Universe up to can be described by a FRW metric. E.g., using the LCS method and the current sample of SNIa we expect in of all cases to detect a higher value for dipole, than the observed one.
Table 1
Isotropy rejection levels using
Cosmological Method
parameter LCS TEMPLATE
33% 70%
81% 79%
88% 64%
## 6 Discussion
By the exploitation of the current available SNe data we have put constraints on the rejection level of the cosmological principle validity up to . A FRW metric is found to be an adequate description of the Universe. In of all realizations of such universes, the dipole signature for anisotropy in the cosmological parameters , and exceeds the observed one.
Even though such dipole magnitudes are reasonable in the framework of the FRW model, they may be indicative of non-cosmological contributions to the angular power spectrum. In §1 we listed possible such contributions. If indeed the Universe up to is well represented by a FRW metric then we can exclude large coherent structures at . Such are the structures that may lead to dipole and quadrupole signatures due to coherent gravitational lensing magnification/de-magnification and therefore the latter can be excluded as anisotropy contributors.
That leaves small scale (Galactic) foreground effects to be the most likely power contributors. The Galactic disk geometry makes the quadrupole the most significant multipole to be considered, though the solar system offset from the Galactic center may bring about a dipole contribution as well. In the current sample the quadrupole term is only slightly larger than the noise level and does not allow any conclusive results. None of the dipole directions for coincides with the Galactic plane and thus they are probably not correlated with it. Multipoles due to dust extinction may be affirmed by multiple expansion of the residual colors after extinction correction (i.e., R98 and P99 appendices).
The one case where two significantly non-overlapping confidence regions are found for two hemispheres that maximize the dipole (LCS), is probably due to a single SN (1995at) for which the individual errors have been underestimated. This case is an exception since the overall values for the HD fits are statistically acceptable. Nevertheless, this case demonstrates the hazard in the draw of conclusions based on a handful of SNe, for which the error in the error estimate is uncertain.
In general, the TEMPLATE method provides a better statistical agreement of the data with an FRW model and the current SNe data. This is seen from the magnitude match (cf. §2), tighter constraints from the combined set, smaller noise levels for all multipoles, and smaller values for the dipoles.
We conclude that an isotropic universe cannot be rejected by more than a level based on the current SNe data.
## Acknowledgments:
This work was supported by the US-Israel Binational Science Foundation, by the Israel Science Foundation, and by grants from NASA and NSF at UCSC.
## References
• Bridle et al. (Bridle et al.)
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• Célérier (2000a) Célérier M., 2000a, A&Ap, 353, 63
• Célérier (2000b) Célérier M., 2000b, in ”Proceedings of the XXXVth Rencontres de Moriond, “Energy Densities in the Universe”, astro-ph/0006273
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• Riess et al. (1998) Riess A. G. et al., 1998, AJ, 116, 1009
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• Webster (Webster)
• Wu, Lahav, & Rees (Wu et al.) | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9148502945899963, "perplexity": 1480.0371142196013}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703550617.50/warc/CC-MAIN-20210124173052-20210124203052-00476.warc.gz"} |
https://www.eevblog.com/forum/testgear/agilent-e7495-linux-root-account/msg618339/ | ### Author Topic: Agilent E7495 linux root account (Read 91111 times)
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#### Urs42
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##### Re: Agilent E7495 linux root account
« Reply #50 on: February 25, 2015, 08:07:21 am »
Quote
The setting can be changed in the setup but it has to be done for each mode, and even then will often revert back to white.
It would be great if someone figured out a way to make black background the default.
Warning: Changes in /flash are permanent! You can brick your device! Don't change anything there if you are not sure what you are doing. Before you do anything there, use tar to back up all files from /flash to the CF or PCMCIA card!
In my first post i mentioned that the power up settings are stored in /flash/egServer/registry/Powerup/ i think that you can't change the powerup configuration with the GUI, but you can configure the device, save the configuration to a profile an then use telnet to copy your profile to /flash/egServer/registry/Powerup/. All profiles are stored as supdirectories of /flash/egServer/registry/
Quote
Must be some of E7495B Linux setting ?
I'm sorry, i can't see anything wrong from here, it's not easy to debug stuff like this without a way to reproduce the issue. I think the Linux on the E7495B isn't the issue here, It could be a hardware issue with your E7495B or some problem with your Network or Computer(s).
#### Wuerstchenhund
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##### Re: Agilent E7495 linux root account
« Reply #51 on: February 25, 2015, 08:23:39 am »
i think that you can't change the powerup configuration with the GUI
Sure you can. Just save your preset as "powerup"
However this doesn't seem to help for the screen capture background setting, which still seems to revert to white.
I also couldn't find a parameter for it in the registry, but maybe I just didn't look hard enough or overlooked something.
#### 9aplus
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##### Re: Agilent E7495 linux root account
« Reply #52 on: February 25, 2015, 09:04:01 am »
Yes, GPS does it automatically.
In that case that is not stored on hwclock or there is no clock backup battery... because my unit was on GPS couple days ago.
I'm sorry, i can't see anything wrong from here, it's not easy to debug stuff like this without a way to reproduce the issue. I think the Linux on the E7495B isn't the issue here, It could be a hardware issue with your E7495B or some problem with your Network or Computer(s).
Thank you for your kind efforts
No rush... after all, with all this I am refreshing my Unix know how
With CF use can pick up necessary data for now... and remote is in to do list.
E7495B must be capable on VXI or USBTMC commands, that may be also god solution for my future remote...
Considering from last night one other way to bring E7485B version of egclient.jar
to Ubuntu PC... by simple copy on CF card, but
path ->
on /flash/mnt/cf/
>ls -al
.
..
empty folder! (some data like screns, xls and update files are on CF for sure....
Anyone, what is right path for my CF card?
Quote
enable_irq(114) unbalanced from c032558c
Trying to free nonexistent resource <ce8a6000-ce8a600f>
hda: SILICONSYSTEMS INC 128MB, ATA DISK drive
ide0 at 0xce8a6000-0xce8a6007,0xce8a600e on irq 114
hda: 254208 sectors (130 MB) w/0KiB Cache, CHS=993/8/32
Partition check:
hda: hda1
ide_cs: hda: Vcc = 3.3, Vpp = 0.0
enable_irq(115) unbalanced from c032558c
Trying to free nonexistent resource <ce8b7000-ce8b700f>
hdc: TS8GCF133, ATA DISK drive
ide1 at 0xce8b7000-0xce8b7007,0xce8b700e on irq 115
hdc: task_no_data_intr: error=0x04 { DriveStatusError }
hdc: 15662304 sectors (8019 MB) w/1KiB Cache, CHS=974/255/63
hdc: hdc1
ide_cs: hdc: Vcc = 3.3, Vpp = 0.0
hda: hda1
hda: hda1
VFS: Can't find ext2 filesystem on dev ide0(3,1).
hda: hda1
hda: hda1
cramfs: wrong magic
hda: hda1
hda: hda1
hdc: hdc1
hdc: hdc1
VFS: Can't find ext2 filesystem on dev ide1(22,1).
hdc: hdc1
hdc: hdc1
cramfs: wrong magic
hdc: hdc1
hdc: hdc1
hda: hda1
hda: hda1
VFS: Can't find ext2 filesystem on dev ide0(3,1).
hda: hda1
hda: hda1
cramfs: wrong magic
hda: hda1
hda: hda1
hdc: hdc1
hdc: hdc1
VFS: Can't find ext2 filesystem on dev ide1(22,1).
hdc: hdc1
hdc: hdc1
cramfs: wrong magic
hdc: hdc1
hdc: hdc1
report same devices with and without PCMCIA and CF card plugged on E7495B
no >lsblk to find out, any other way to do it?
Quote
[root@E749xx /root]$mount rootfs on / type rootfs (rw) /dev/root on / type ext2 (rw) /proc on /proc type proc (rw) none on /dev/pts type devpts (rw) /dev/mtdb3 on /flash type jffs2 (rw) « Last Edit: February 25, 2015, 03:21:37 pm by 9aplus » #### Wuerstchenhund • Super Contributor • Posts: 3056 • Country: ##### Re: Agilent E7495 linux root account « Reply #53 on: February 25, 2015, 03:45:37 pm » Yes, GPS does it automatically. In that case that is not stored on hwclock or there is no clock backup battery... because my unit was on GPS couple days ago. I didn't check but without a charged battery in the battery bays or PSU power it will probably forget the date/time as I doubt it has a separate backup battery. Quote Considering from last night one other way to bring E7485B version of egclient.jar to Ubuntu PC... by simple copy on CF card, but path -> on /flash/mnt/cf/ >ls -al . .. empty folder! (some data like screns, xls and update files are on CF for sure.... You *did* mount the card in the E7495 before you tried to access it, didn't you? Quote Anyone, what is right path for my CF card? Now that's really easy. It says it right there (I highlighted the relevant part in bold): Quote enable_irq(114) unbalanced from c032558c Trying to free nonexistent resource <ce8a6000-ce8a600f> hda: SILICONSYSTEMS INC 128MB, ATA DISK drive ide0 at 0xce8a6000-0xce8a6007,0xce8a600e on irq 114 hda: 254208 sectors (130 MB) w/0KiB Cache, CHS=993/8/32 Partition check: hda: hda1 ide_cs: hda: Vcc = 3.3, Vpp = 0.0 enable_irq(115) unbalanced from c032558c Trying to free nonexistent resource <ce8b7000-ce8b700f> hdc: TS8GCF133, ATA DISK drive ide1 at 0xce8b7000-0xce8b7007,0xce8b700e on irq 115 hdc: task_no_data_intr: status=0x51 { DriveReady SeekComplete Error } hdc: task_no_data_intr: error=0x04 { DriveStatusError } hdc: 15662304 sectors (8019 MB) w/1KiB Cache, CHS=974/255/63 hdc: hdc1 ide_cs: hdc: Vcc = 3.3, Vpp = 0.0 hda: hda1 hda: hda1 VFS: Can't find ext2 filesystem on dev ide0(3,1). hda: hda1 hda: hda1 cramfs: wrong magic hda: hda1 hda: hda1 hdc: hdc1 hdc: hdc1 VFS: Can't find ext2 filesystem on dev ide1(22,1). hdc: hdc1 hdc: hdc1 cramfs: wrong magic hdc: hdc1 hdc: hdc1 hda: hda1 hda: hda1 VFS: Can't find ext2 filesystem on dev ide0(3,1). hda: hda1 hda: hda1 cramfs: wrong magic hda: hda1 hda: hda1 hdc: hdc1 hdc: hdc1 VFS: Can't find ext2 filesystem on dev ide1(22,1). hdc: hdc1 hdc: hdc1 cramfs: wrong magic hdc: hdc1 hdc: hdc1 It seems you're using a Transcend 8GB 133x Compact Flash card. But the error messages shouldn't be there. Is the card formatted properly (FAT32)? Quote Asking because >mount report same devices with and without PCMCIA and CF card plugged on E7495B no >lsblk to find out, any other way to do it? Quote Easy: Code: [Select] # mount /dev/hdc1 /mnt If you want to access the PCMCIA flash card (or a CF card in a PCMCIA adapter) then it's /dec/hda1 instead. « Last Edit: February 25, 2015, 03:52:28 pm by Wuerstchenhund » #### Urs42 • Supporter • Posts: 142 • Country: ##### Re: Agilent E7495 linux root account « Reply #54 on: February 25, 2015, 04:08:51 pm » Quote I didn't check but without a charged battery in the battery bays or PSU power it will probably forget the date/time as I doubt it has a separate backup battery. Some init script stores date and time at shutdown to a file in /flash, this date will be restored at the next boot. Quote hdc: TS8GCF133, ATA DISK drive ide1 at 0xce8b7000-0xce8b7007,0xce8b700e on irq 115 hdc: task_no_data_intr: status=0x51 { DriveReady SeekComplete Error } hdc: task_no_data_intr: error=0x04 { DriveStatusError } hdc: 15662304 sectors (8019 MB) w/1KiB Cache, CHS=974/255/63 hdc: hdc1 I'm not sure if this is a critical error, some CF/PCMCIA cards will produce errors like this one, because they don't understand all command that the kernel sends to them while initializing the card. #### 9aplus • Regular Contributor • Posts: 126 ##### Re: Agilent E7495 linux root account « Reply #55 on: February 25, 2015, 05:32:38 pm » CF card is formated properly. That's the same one from which update to A.06.25 is performed Well I didn't check but without a charged battery in the battery bays or PSU power it will probably forget the date/time as I doubt it has a separate backup battery. You *did* mount the card in the E7495 before you tried to access it, didn't you? My date went crazy again, both accu was inside unit.... Quote [root@E749xx /root]$date
Wed Feb 25 02:10:32 UTC 2015
[root@E749xx /root]$hwtime bash: hwtime: command not found [root@E749xx /root]$hwclock
Wed Feb 25 06:53:49 2015 -0.763275 seconds
[root@E749xx /root]$Well my expectation was that the system already done that for me.... Thank you to both of you Must try advices, than report later.... « Last Edit: February 25, 2015, 05:39:48 pm by 9aplus » #### 9aplus • Regular Contributor • Posts: 126 ##### Re: Agilent E7495 linux root account « Reply #56 on: February 25, 2015, 05:52:51 pm » Done... on second attempt after reboot Quote [root@E749xx /root]$mount /dev/hdc1 /mnt
[root@E749xx /root]$mount rootfs on / type rootfs (rw) /dev/root on / type ext2 (rw) /proc on /proc type proc (rw) none on /dev/pts type devpts (rw) /dev/mtdb3 on /flash type jffs2 (rw) /dev/hdc1 on /mnt type vfat (rw) [root@E749xx /root]$
#### Wuerstchenhund
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##### Re: Agilent E7495 linux root account
« Reply #57 on: February 25, 2015, 07:31:56 pm »
Some init script stores date and time at shutdown to a file in /flash, this date will be restored at the next boot.
Yes, but that is only to avoid that new files are written with older timestamps than existing files.
Quote
I'm not sure if this is a critical error, some CF/PCMCIA cards will produce errors like this one, because they don't understand all command that the kernel sends to them while initializing the card.
In my experience (I use CF cards a lot for embedded stuff) the Transcend cards are often more problematic than say Sandisk or Apacer. Especially when they are treated as a fixed disk (like in the E7495) and not like a removable device.
However, I have used similar cards (same model, just 1GB and 16GB instead of 8GB) and didn't see such errors.
#### Wuerstchenhund
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##### Re: Agilent E7495 linux root account
« Reply #58 on: February 25, 2015, 07:41:32 pm »
Well my expectation was that the system already done that for me....
Both CF and PCMCIA storage remain unmounted until you press the screen shot button or save some measurement data, where the card gets mounted, written to and unmounted. Ever wondered why saving a simple screen shot takes so long? That's why.
This way the cards can be removed while the E7495 is still running.
#### 9aplus
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• Posts: 126
##### Re: Agilent E7495 linux root account
« Reply #59 on: February 25, 2015, 09:30:08 pm »
Last session ->
Quote
[root@E749xx /root]$mount /dev/hdc1 /mnt [root@E749xx /root]$mount
rootfs on / type rootfs (rw)
/dev/root on / type ext2 (rw)
/proc on /proc type proc (rw)
none on /dev/pts type devpts (rw)
/dev/mtdb3 on /flash type jffs2 (rw)
/dev/hdc1 on /mnt type vfat (rw)
[root@E749xx /root]$cd .. [root@E749xx /]$cd ..
[root@E749xx /]$ls bin flash linuxrc nfs root usr dev home lost+found proc sbin var etc lib mnt rd tmp xdrive [root@E749xx /]$cd flash
[root@E749xx /flash]$cd egGui [root@E749xx egGui]$ls
JimiProClasses.zip rhino-1.5R4.jar xerces.jar
egclient.jar shellexec.log
libguiutil.so swing.jar
[root@E749xx egGui]$cp egclient.jar /dev/hdc1 [root@E749xx egGui]$umount /dev/hdc1
[root@E749xx egGui]$mount rootfs on / type rootfs (rw) /dev/root on / type ext2 (rw) /proc on /proc type proc (rw) none on /dev/pts type devpts (rw) /dev/mtdb3 on /flash type jffs2 (rw) [root@E749xx egGui]$
This is 4th try and failure.... after >cp on CF card file system is gone, full format on Win PC help to restore... data and screen copy
on same CF goes well....
#### CustomEngineerer
• Frequent Contributor
• Posts: 459
• Country:
##### Re: Agilent E7495 linux root account
« Reply #60 on: February 26, 2015, 02:53:27 am »
Last session ->
Quote
[root@E749xx /root]$mount /dev/hdc1 /mnt [root@E749xx /root]$mount
rootfs on / type rootfs (rw)
/dev/root on / type ext2 (rw)
/proc on /proc type proc (rw)
none on /dev/pts type devpts (rw)
/dev/mtdb3 on /flash type jffs2 (rw)
/dev/hdc1 on /mnt type vfat (rw)
[root@E749xx /root]$cd .. [root@E749xx /]$cd ..
[root@E749xx /]$ls bin flash linuxrc nfs root usr dev home lost+found proc sbin var etc lib mnt rd tmp xdrive [root@E749xx /]$cd flash
[root@E749xx /flash]$cd egGui [root@E749xx egGui]$ls
JimiProClasses.zip rhino-1.5R4.jar xerces.jar
egclient.jar shellexec.log
libguiutil.so swing.jar
[root@E749xx egGui]$cp egclient.jar /dev/hdc1 [root@E749xx egGui]$umount /dev/hdc1
[root@E749xx egGui]$mount rootfs on / type rootfs (rw) /dev/root on / type ext2 (rw) /proc on /proc type proc (rw) none on /dev/pts type devpts (rw) /dev/mtdb3 on /flash type jffs2 (rw) [root@E749xx egGui]$
This is 4th try and failure.... after >cp on CF card file system is gone, full format on Win PC help to restore... data and screen copy
on same CF goes well....
Your syntax is a little off. "cp egclient.jar /dev/hdc1" is copying egclient.jar over the hdc1 device, not into it. I didn't think unix/linux would actually let you do that. My guess is that it wrote egclient.jar starting at the beginning of the cf card and overwrote the partition table which is why the file system is gone. The correct syntax would be "cp egclient.jar /dev/hdc1/", notice the trailing front slash after hdc1. Though I still would not recommend doing it this way. I would reformat the the CF card, mount it and then copy it with this command. "cp egclient.jar /mnt/" Again, make sure you get the trailing front slash.
« Last Edit: February 26, 2015, 02:58:03 am by CustomEngineerer »
#### ldhn1uec
• Newbie
• Posts: 3
##### Re: Agilent E7495 linux root account
« Reply #61 on: February 26, 2015, 12:35:57 pm »
New to the group, new to the unit. At the hamcation flea market i picked up 4 units, all "broken", seems they all work to some extent. one has a broken lcd, all took the firmware upgrade. all have slightly different opotions. dissasembled and reassembled cracked unit, it still works and is useable with remote software. saw some talk of the download issues, check any/all firewall settings on the host pc as the file is pulled from the pc within the java parent. i had trouble until i used the early 1.4 java package. that worked well on xp and still works on w7. starting to look into modifying the options, i'll post results here. i will also mention that since this is an older unit, don't use cf larger than 2g due to changes in sector sizes. find a 64 or 128 MEG cf card for transfers and you'll have much fewer problems. hope that helps.
Lou... N1UEC
Sent from my iPad using Tapatalk
#### 9aplus
• Regular Contributor
• Posts: 126
##### Re: Agilent E7495 linux root account
« Reply #62 on: February 26, 2015, 07:42:56 pm »
@CustomEngineerer thank you, that was useful tip, copy now in order
Concerning overall progress, something still missing..... Correct path maybe?
RemoteGui.jar is not able to start egclient.jar, even not when all are within Home folder
When run alone egclient.jar makes this screen, and it is not possible to quit OpenJDK Java 6 Runtime.
#### CustomEngineerer
• Frequent Contributor
• Posts: 459
• Country:
##### Re: Agilent E7495 linux root account
« Reply #63 on: February 27, 2015, 01:09:23 am »
@CustomEngineerer thank you, that was useful tip, copy now in order
Concerning overall progress, something still missing..... Correct path maybe?
RemoteGui.jar is not able to start egclient.jar, even not when all are within Home folder
When run alone egclient.jar makes this screen, and it is not possible to quit OpenJDK Java 6 Runtime.
Glad you were able to get the copy done. For what's going wrong now all I can think of is to make sure that you are starting RemoteGui.jar like Urs42 suggested in Reply #35. Pasting it below. Also note that the command is a little different than when he first suggested it back in Reply #29. Good luck.
Quote
It loos like you are running the command in your home directory, that won't work. Run it in the directory where all the java files are.
I pasted the wrong command line, please replace egclient-patch.jar with egclient.jar
Code: [Select]
java -Dserver=192.168.1.209 -DlocalAddress=192.168.1.205 -classpath "egclient.jar:xerces.jar:JimiProClasses.zip:RemoteGui.jar" elgato.gui.MainWindow
#### 9aplus
• Regular Contributor
• Posts: 126
##### Re: Agilent E7495 linux root account
« Reply #64 on: February 27, 2015, 12:35:43 pm »
Yes, you are right, just forgot on that advice...
Now all running well
(except ftp file transfer, but who cares)
Like to thank to all of you. for kind assistance and patience
on this small E7495B tutorial on Java & Linux
#### 9aplus
• Regular Contributor
• Posts: 126
##### Re: Agilent E7495 linux root account
« Reply #65 on: February 27, 2015, 06:44:39 pm »
Java application running but something is still not good regarding communication ->
Quote
q@ubuntu:~/Desktop$cd E7495xRemoteGui q@ubuntu:~/Desktop/E7495xRemoteGui$ java -Dserver=192.168.1.209 -DlocalAddress=192.168.1.205 -classpath "egclient.jar:xerces.jar:JimiProClasses.zip:RemoteGui.jar" elgato.gui.MainWindow
1425060510121 INFO util.Resources Loaded resource file: /elgato/system.properties
1425060510182 INFO util.Resources Loaded resource file: /elgato/gui.properties
1425060510790 INFO util.LocaleManager No locale set, using default.
1425060512755 INFO util.Resources Loaded resource file: /elgato/infrastructure.properties
1425060518929 INFO util.DebugServer DebugServer started on port 5100
1425060519272 INFO gui.MainWindow Display area: java.awt.Dimension[width=472,height=414]
1425060519529 INFO commChannel.DefaultCommandProcessor STATUS: Startup in process...
1425060519725 INFO commChannel.DefaultCommandProcessor STATUS: Startup complete.
1425060521582 INFO commChannel.UDPMeasurementReader Binding to DatagramSocket
1425060521583 INFO commChannel.UDPMeasurementReader Bound to UDP port 37537
1425060522662 INFO mainScreens.ProductFactory Instantiating El Gato Product Factory (class ElgatoFactory)
1425060545849 INFO util.Resources Loaded resource file: /elgato/measurement.properties
1425060674497 INFO util.Resources Loaded resource file: /help/help.properties
1425062015101 ERROR: util.FileSystemHelper saveImage(null, /tmpscreenTmp.png, image, true):
null
com.sun.jimi.core.JimiException
at com.sun.jimi.core.JimiWriter.putImage(JimiWriter.java:242)
at com.sun.jimi.core.Jimi.putImage(Jimi.java:601)
at com.sun.jimi.core.Jimi.putImage(Jimi.java:587)
at com.sun.jimi.core.Jimi.putImage(Jimi.java:575)
at elgato.infrastructure.util.FileSystemHelper.saveImage(Unknown Source)
at elgato.infrastructure.util.FileSystemHelper.saveImage(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.decorateImage(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.saveScreenImage(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.printScreen(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.commitAction(Unknown Source)
at elgato.infrastructure.mainScreens.MediaMessageScreen.run(Unknown Source)
1425062015219 ERROR: widgets.ImageIcon Timed out waiting for image to load
1425062015220 WARN mainScreens.PrintScreenMessageScreen decorateImage: No addition of filename to screen capture image...java.lang.IllegalArgumentException: Width (-1) and height (45) cannot be <= 0
1425062015220 ERROR: util.FileSystemHelper saveImage(null, /tmp/printScreen_20150127_193334.png, image, true):
null
java.lang.NullPointerException
at com.sun.jimi.core.Jimi.putImage(Jimi.java:575)
at elgato.infrastructure.util.FileSystemHelper.saveImage(Unknown Source)
at elgato.infrastructure.util.FileSystemHelper.saveImage(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.saveScreenImage(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.printScreen(Unknown Source)
at elgato.infrastructure.mainScreens.PrintScreenMessageScreen.commitAction(Unknown Source)
at elgato.infrastructure.mainScreens.MediaMessageScreen.run(Unknown Source)
1425062436333 ERROR: util.DebugServer Couldn't accept connection
Socket closed
java.net.SocketException: Socket closed
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.AbstractPlainSocketImpl.accept(AbstractPlainSocketImpl.java:375)
at java.net.ServerSocket.implAccept(ServerSocket.java:478)
at java.net.ServerSocket.accept(ServerSocket.java:446)
at elgato.infrastructure.util.DebugServer.run(Unknown Source)
1425062436335 INFO util.DebugServer DebugServer stopped
1425062436341 WARN commChannel.UDPMeasurementReader Error reading measurement packet, ignoring: java.net.SocketException: Socket closedq@ubuntu:~/Desktop/E7495xRemoteGui$#### jwm_ • Frequent Contributor • Posts: 318 • Country: ##### Re: Agilent E7495 linux root account « Reply #66 on: February 27, 2015, 11:32:32 pm » got my E7495A for repair but without any accesories or charger. can someone tell me the polarity/voltage of the external power port? #### Wuerstchenhund • Super Contributor • Posts: 3056 • Country: ##### Re: Agilent E7495 linux root account « Reply #67 on: February 28, 2015, 08:36:15 am » got my E7495A for repair but without any accesories or charger. can someone tell me the polarity/voltage of the external power port? 24Vdc, positive inside, negative outside #### Wuerstchenhund • Super Contributor • Posts: 3056 • Country: ##### Re: Agilent E7495 linux root account « Reply #68 on: February 28, 2015, 08:51:06 am » The E7495 firmware looks very much the same as for the N1996 CSA SA It would be interesting to find out how similar the hardware is, and if some of the capabilities of the N1996A could be transferred to the E7495. #### PA0PBZ • Super Contributor • Posts: 4521 • Country: ##### Re: Agilent E7495 linux root account « Reply #69 on: February 28, 2015, 09:11:42 am » The E7495 firmware looks very much the same as for the N1996 CSA SA It would be interesting to find out how similar the hardware is, and if some of the capabilities of the N1996A could be transferred to the E7495. It would be nice to have a service manual for either, but I only found the N1996A one at Agilent for about$400
Keyboard error: Press F1 to continue.
#### 9aplus
• Regular Contributor
• Posts: 126
##### Re: Agilent E7495 linux root account
« Reply #70 on: February 28, 2015, 10:00:55 am »
got my E7495A for repair but without any accesories or charger. can someone tell me the polarity/voltage of the external power port?
24Vdc, positive inside, negative outside
100W PS -> 4+ A current
#### ldhn1uec
• Newbie
• Posts: 3
##### Re: Agilent E7495 linux root account
« Reply #71 on: February 28, 2015, 09:58:00 pm »
so, i have found the power supply can bve almost anything with a + center. the spec for the instrument is 10-24 volts at least 65 watts. 12v 5 amps works fine, as well as 19.8v and 4.14a.
my tinkering is going well. DO NOT ALTER the lower limit of the receivers as that will cause the system to fault. 375 is the actual \low limit. (was trying to squeeze vhf out of the swr bridge).
still comparing the dumps of the 4 units to decode the licensing arrangement. does seem that the only changes are the lic files as the other files are present anyway.
anyone have luck rebuilding or replacing the li-ion batteries?
as far as the remote gui, no joy on java 6, go back to java 1.4.2 and all was well. don't forget the loc/remote button to enable full control from the pc. even with a cracked lcd the remote software allows me to work with it.
so far so good 3/4 are working and 1 works but is -10db on spectrum
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#### 9aplus
• Regular Contributor
• Posts: 126
##### Re: Agilent E7495 linux root account
« Reply #72 on: March 01, 2015, 10:45:10 am »
Quote
as far as the remote gui, no joy on java 6, go back to java 1.4.2 and all was well.
You are running 1.4.2 on windows ?
Which one ? My try on Win 7 no luck....
How do you run remote gui on Win os?
#### Urs42
• Supporter
• Posts: 142
• Country:
##### Re: Agilent E7495 linux root account
« Reply #73 on: March 01, 2015, 05:31:31 pm »
Quote
my tinkering is going well. DO NOT ALTER the lower limit of the receivers as that will cause the system to fault. 375 is the actual \low limit. (was trying to squeeze vhf out of the swr bridge).
Do you have the A or B model? The range of the E7495B goes from 10MHz to 2.7GHz, but the preamplifiers only go down to 375 MHz. 10MHz is written on the front panel, but i can enter frequencies down to 500KHz.
#### ldhn1uec
• Newbie
• Posts: 3
##### Re: Agilent E7495 linux root account
« Reply #74 on: March 02, 2015, 03:00:39 am »
i have the 7495A. the spectrum analyzers go down fine, the swr bridge/return loss port will not go below 375m
as far as the gui, you need to uninstall java completely, go to the java site archives and get the 1.4.2 java package and install it. then the gui parts work fine. when i get round to it i may try 6.
attempted to swap lic&hostid files with no luck. seems to be more involved. may try the patch listed above.
Sent from my iPad using Tapatalk
Smf | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2035582959651947, "perplexity": 19819.778070482906}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703557462.87/warc/CC-MAIN-20210124204052-20210124234052-00279.warc.gz"} |
http://crypto.stackexchange.com/users/6875/javic?tab=activity&sort=comments | # javic
less info
reputation
3
bio website location age member for 1 year, 2 months seen Apr 23 at 22:13 profile views 0
# 1 Comment
May6 comment RSA leak bits to factor N Ah I see! Thanks for pointing out that paper. Seems like a very good summary of what you can do with RSA. It appears that $n/4$ (or $k/2$ for $k$ bit $p,q$) is the best bound out there then. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.48413559794425964, "perplexity": 1780.126675740727}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1406510274289.5/warc/CC-MAIN-20140728011754-00001-ip-10-146-231-18.ec2.internal.warc.gz"} |
http://forums.scribus.net/index.php?action=printpage;topic=210.0 | # Scribus Forums
## Scribus => Text and Typography => Topic started by: anandharaja on September 09, 2011, 07:26:58 pm
Title: How to type Scientific formula inside scribus
Post by: anandharaja on September 09, 2011, 07:26:58 pm
hi,
i want type more pages with equations and more scientific formula, how can i type formulas inside scribus.
i know installing latex will help to type forumula's. but i want GUI window for typing formula.
Currently i using windows 7 64bit OS.
Title: Re: How to type Scientific formula inside scribus
Post by: WalksIn2Trees on September 09, 2011, 08:28:28 pm
that would be where the latex tool comes in
Title: Re: How to type Scientific formula inside scribus
Post by: anandharaja on September 10, 2011, 06:18:04 am
i confused about selecting the latex.
which one i choose Klatex or Miktex or any other latex?
Title: Re: How to type Scientific formula inside scribus
Post by: anandharaja on September 11, 2011, 09:18:15 am
Just now i installed Klatex. how can i configure Klatex with scribus?
Title: Re: How to type Scientific formula inside scribus
Post by: Meho R. on September 19, 2011, 03:18:51 pm
I have no idea what klatex is, but TeXLive and MikTeX are full-blown installation containing everything one might need. So,
1. You'll need installation of LaTeX on your computer (TeXLive or MikTeX). Test it out of Scribus to see if everything is set.
2. Scribus should recognize LaTeX installation automatically. However, if you need to change anything related to communication with LaTeX, take a look at File > Preferences > External Tools.
3. In Scribus, create a Render Frame > right click > Edit Source... Here you'll enter the code to render your formula. E.g., with "Use Preamble" turned off, try this in "Enter Code" section:
Code: [Select]
\documentclass{article}\begin{document}Testing \LaTeX:$x-y=z$And inline: $x-y=z$.\end{document}
4. When exporting your document to PDF, make sure you activate "Embed PDF & EPS Files" checkbox, so that the content of the Render Frame gets exported as vector, not as bitmap.
Title: Re: How to type Scientific formula inside scribus
Post by: anandharaja on September 27, 2011, 07:48:02 pm
@ Meho R
Thanks for reply, ok i try MikTex. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 2, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8925459384918213, "perplexity": 14313.878280265724}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514573284.48/warc/CC-MAIN-20190918110932-20190918132932-00436.warc.gz"} |
https://wwrenderer-staging.libretexts.org/render-api?sourceFilePath=Library/Utah/Quantitative_Analysis/set6_Applications_of_Derivatives/pr_9.pg&problemSeed=1234567&courseID=anonymous&userID=anonymous&course_password=anonymous&answersSubmitted=0&showSummary=1&displayMode=MathJax&language=en&outputFormat=nosubmit | Consider the function $f(x) = 3 x + 6 x ^ { -1 }$. For this function there are four important intervals: $(-\infty, A]$, $[A,B)$,$(B,C)$, and $[C,\infty)$ where $A$, and $C$ are the critical numbers and the function is not defined at $B$.
Find $A$
and $B$
and $C$
For each of the following intervals, tell whether $f(x)$ is increasing (type in INC) or decreasing (type in DEC).
$(-\infty, A]$:
$[A,B)$:
$(B,C]$:
$[C,\infty)$:
You can earn partial credit on this problem. | {"extraction_info": {"found_math": true, "script_math_tex": 16, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9633012413978577, "perplexity": 305.61224125053235}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764499819.32/warc/CC-MAIN-20230130133622-20230130163622-00555.warc.gz"} |
http://mathhelpforum.com/calculus/60420-evaluating-integral.html | # Math Help - Evaluating integral...
1. ## Evaluating integral...
How to use cylindrical or spherical coordinates as appropriate to evaluate the integral:
∫ z^2/(x^2+y^2+z^2) dV
E
where E is the top half of a sphere of radius a>0 that is centered at the origin.
Thankyou for your help!!
2. I came up with this...
Is this correct?
3. Hello,
Hmmm I'm finding $\cos^2(\phi)$ instead of $\cos(\phi)$
Also, there is that coefficient, 2, disturbing me. We once calculated the dxdydz, and my friend found this coefficient. I wasn't able to find the mistake in either of our two computations.
But in the wikipedia, there isn't this coefficient.
As for the boundaries of your integral, it depends on how you define $\theta$ and $\phi$
4. Originally Posted by Moo
As for the boundaries of your integral, it depends on how you define $\theta$ and $\phi$
$\theta$ is the polar $\theta$ and $\phi$ is the angle of opening from the z-axis. So $\phi$ from 0 to $\frac{\pi}{2}$ would be like a coffee filter completely closed up along the z-axis and then blossoming outward and to rest on the xy-plane.
In regards to the question, I'm confused about where the 2 is coming from as well...I will ponder this a little more. Any insight into how you came up with the 2? I'm just not seeing it.
5. Originally Posted by iwonder
I came up with this...
Is this correct?
Your limits of integration are fine, but remember that from rectangular to polar $z=\rho\cos{\phi}$ and $x^2+y^2+z^2=\rho^2$. So $\frac{z^2}{x^2+y^2+z^2}=\frac{\rho^2\cos^2{\phi}}{ \rho^2}=\cos^2{\phi}$.
So, then the integral becomes $\int_0^{2\pi}\int_0^a\int_0^\frac{\pi}{2}\rho^2\co s^2\phi\sin\phi d\phi d\rho d\theta$
Perhaps your two came from a trig identity, I'm too tired to think about it..if it came from an identity then it's fine.
Also, I have my integration in a little bit different order than you, but since we are in spherical coordinates and the sphere is centered at the origin we can flip the integration limits arbitrarily.
I think this is all correct...good luck
6. So, is the first limit of integration from 0 to 2/pi or 2pi?
just wanna make sure, thankyou so much!
7. Originally Posted by iwonder
So, is the first limit of integration from 0 to 2/pi or 2pi?
just wanna make sure, thankyou so much!
Should be zero to (2*pi) bad latex! I will edit to avoid confusion. sorry about that!
8. It's okay, thanks elizsimca so much!!!!
i already got the answer (2(pi)a^3)/9, hope this is the right answer. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 15, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9797366857528687, "perplexity": 696.1826139207202}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-22/segments/1464049273946.43/warc/CC-MAIN-20160524002113-00003-ip-10-185-217-139.ec2.internal.warc.gz"} |
https://link.springer.com/article/10.1007/s12651-016-0208-y | Journal for Labour Market Research
, Volume 49, Issue 3, pp 253–268
# Overqualification of graduates: assessing the role of family background
• Daniel Erdsiek
Open Access
Article
## Abstract
Overqualification signals a mismatch between jobs’ educational requirements and workers’ qualifications implying potential productivity losses at the macro and the micro level. This study explores how the family background of German graduates affects the probability to hold a job that does not require tertiary education, i.e. to be overqualified. Potential pathways of the family background effects are discussed and proxy variables for the mediating factors ability and skills, study characteristics, social capital, financial capital, and aspiration are incorporated into the empirical analysis. Graduates from high status families are found to be less likely to be overqualified. The unconditional social overqualification gap amounts to 7.4 percentage points. Blinder-Oaxaca decompositions of the overqualification gap show that differences in ability and skills, study characteristics, and social capital are important mediators of the family background effects.
## Keywords
Overqualification Overeducation Family background Intergenerational mobility Blinder–Oaxaca decomposition
# Überqualifikation von Hochschulabsolventen: Welche Rolle spielt der familiäre Hintergrund?
## Zusammenfassung
Ein Mismatch zwischen den Anforderungen einer beruflichen Beschäftigung und den Fähigkeiten eines Arbeitnehmers kann Produktivitätsverluste auf der individuellen sowie gesamtwirtschaftlichen Ebene verursachen, weil das verfügbare Humankapital nicht ausreichend genutzt wird. Überqualifikation beschreibt eine entsprechende Situation in der ein Mismatch vorliegt, weil die Beschäftigung nicht den formalen Bildungsabschluss erfordert, den der Arbeitnehmer erworben hat. Diese Studie untersucht, inwieweit der familiäre Hintergrund von Hochschulabsolventen die Wahrscheinlichkeit beeinflusst, überqualifiziert beschäftigt zu sein. Mögliche Wirkungsmechanismen für einen Effekt der sozialen Herkunft werden diskutiert und anhand von Proxy-Variablen für die folgenden potentiellen Einflussfaktoren empirisch untersucht: individuelle Fähigkeiten, Charakteristika des Studiums, soziales Kapital, finanzielles Kapital und Karriereorientierung. Wie die Ergebnisse zeigen, sind Hochschulabsolventen aus Akademikerhaushalten seltener überqualifiziert beschäftigt als Bildungsaufsteiger – also Absolventen, deren Eltern nicht über einen Hochschulabschluss verfügen. Die Differenz der Überqualifikationsraten dieser beiden Absolventengruppen beträgt 7,4 Prozentpunkte. Eine Blinder-Oaxaca Dekomposition dieser Differenz zeigt, dass individuelle Fähigkeiten, Studieneigenschaften und soziales Kapital wichtige Wirkungsmechanismen für den Einfluss des familiären Hintergrunds auf das Risiko einer Überqualifikation darstellen.
I23 I24 J24 J62
## 1 Introduction
A large number of theoretical and empirical studies show that human capital is an important determinant of economic growth. Human capital captures the aggregate amount of skills and knowledge inherent in an economy’s workforce. It is one of the main pillars of the European strategy for economic growth to promote human capital formation (EU2020). One related target is that a share of 40 % of the population aged 30–34 will hold a tertiary degree by the year 2020 (European Commission 2010). However, human capital per se does not facilitate growth. In order to increase output, the stock of skills and knowledge has to be deployed by workers in the execution of tasks. Reaping the benefits of human capital investments requires that workers hold adequate jobs that make efficient use of their skills. Otherwise, imbalances between employer needs and skills of the workforce can lead to an underutilisation of the available human capital hampering economic growth. According to assignment theory, high-skilled workers holding jobs with low skill requirements underutilise their human capital and do not reach their individual production capacity (Sattinger 1993). In the literature, such vertical mismatches are commonly identified in terms of overqualification arising if individuals’ current qualification exceeds the educational requirement of their job.
Overqualification entails productivity-related implications for both economies and individuals. At the aggregate level, reallocating mismatched workers to appropriate jobs could increase productivity and GDP (Gautier and Teulings 2015; McGowan and Andrews 2015). Thus, overqualification implies a potential waste and misallocation of scarce public resources, in particular those public funds invested into education (Chevalier 2003). At the individual level, mainly productivity-related outcomes, such as job satisfaction or wages, have been analysed (Hartog 2000). These studies commonly find that overqualified workers are less satisfied with their job which could reduce workers’ motivation and effort leading to lower productivity (Hersch 1991; Korpi and Tåhlin 2009). Concerning the effects on wages, overqualified workers are found to earn more than their well-matched co-workers because surplus schooling is rewarded (Duncan and Hoffman 1981). However, the return on surplus schooling is commonly found to be lower than the return on years of schooling required for a job (Hartog 2000). Therefore, overqualified workers are found to earn less than equally educated workers holding a matching job (Büchel and Mertens 2004; Daly et al. 2000). Further studies also indicate that overqualification comes along with significant wage penalties for the subgroup of graduates (Chevalier 2003; Diem and Wolter 2014). As discussed by Tsai (2010) and others, negative wage effects might partly arise from a selection of less able individuals into overqualification because individuals holding the same qualification might differ in (innate) ability. In this case, overqualification would not represent an underutilisation of available skills. Recent studies controlling for the skill-heterogeneity between equally educated individuals produced mixed results concerning the causal interpretation of the wage penalty for overqualification. In some studies the negative wage effect of overqualification vanishes once skill-heterogeneity is accounted for (Bauer 2002; Tsai 2010), while other studies find robust wage penalties (Kleibrink 2015; Korpi and Tåhlin 2009). Since previous findings suggest that overqualification is detrimental at the macro and the micro level, understanding the causes for the occurrence of mismatches is highly relevant from a policy perspective.
This study explores which factors are relevant determinants of overqualification among university graduates. Concentrating on the subgroup of graduates is meaningful from a policy perspective since increasing the share of high-skilled workers is an important strategy to promote economic growth. A further aim of policies that improve the access to higher education is to increase intergenerational social mobility. A higher social mobility might in turn enhance growth through a better allocation of human capital resources inherent in individuals from disadvantaged family backgrounds (OECD 2010). In order to promote growth through social mobility, these human capital resources have to be put into productive use in the labour market. It is a special focus of this study to assess the importance of family background as a potential determinant of overqualification. In this context, the outcome variable of overqualification can be interpreted in two ways that are closely related. First, from a growth perspective, overqualification can be interpreted as an indication for putting the skills and knowledge acquired during tertiary education into productive use in the job. This interpretation depicts whether graduates from disadvantaged family backgrounds utilise their human capital efficiently in order to promote economic growth. Second, overqualification can be interpreted as an alternative indicator for individual labour market success since it is related to lower job satisfaction and lower wages. This interpretation is relevant from a social mobility perspective in order to assess whether graduates from disadvantaged family backgrounds reap the benefits of higher education to the same extent as graduates from high status families.
This study contributes to the literature on the determinants of overqualification. Family background has been included in few studies on overqualification determinants, however only as additional control variable (Boll and Leppin 2013; Fehse and Kerst 2007). In the present study, this relationship is the focal point of the analysis. The main aim is to uncover potential transmission channels mediating the link between family background and overqualification. Depending on the family background, graduates might differ in various characteristics that are potential determinants of overqualification. For instance, (innate) ability and cognitive skills are transmitted within families (Black et al. 2009) and decrease the probability of being overqualified (Büchel and Pollmann-Schult 2004). Similarly, the choice of field of study is affected by family background (Jonsson et al. 2009) and is a crucial determinant of overqualification (Dolton and Vignoles 2000). Using data of the HIS-Graduate Panel 1997, I include a set of proxy variables which account for potential factors mediating the link between social origin and overqualification. These factors include ability and skills, study characteristics, financial capital, social capital, and aspiration. Employing a Blinder–Oaxaca decomposition approach, I then analyse which share of the social overqualification gap can be attributed to differences in these factors. The relative importance of the mediating factors is evaluated by conducting a detailed decomposition of the overqualification gap.
The empirical analysis shows that the risk of overqualification depends on the family background of graduates. Based on parental education (PE), graduates are divided into two groups: They either originate from a family with at least one parent holding a tertiary degree (high PE) or from a family with neither of the parents holding a tertiary degree (low PE). As compared to graduates from low PE families, graduates from high PE families are found to be less likely to hold a job that does not require a tertiary degree, i.e. to be overqualified. The unconditional overqualification gap between graduates from low PE families and graduates from high PE families amounts to 7.4 percentage points. The effect of family background is reduced but remains highly significant if the potential pathways are accounted for in a probit regression. Blinder–Oaxaca decompositions show that roughly 60 % of the social overqualification gap can be attributed to the fact that graduates differ in observable characteristics, i.e. the endowments effect. I find that differences in ability and skills, study characteristics, and social capital are significant mediators of the link between family background and overqualification. The most important pathway is the social difference in the choice of university type and subject pointing to the importance of the horizontal dimension of higher education. In contrast, I find little evidence that financial support or aspiration mediate family background effects on overqualification. However, this result might be influenced by the imprecise measures for these factors.
The remainder of the paper is organised as follows. Section 2 presents the related literature and elaborates on potential pathways for family background affecting the risk of overqualification. In Sect. 3 the data are introduced and in Sect. 4 the econometric methodology is described. In Sect. 5 the results are presented and the conclusion is provided in Sect. 6.
## 2 Pathways for family background effects
This section discusses why family background might influence the risk of overqualification and presents potential pathways for the family background effect. Empirical evidence on both the relevant determinants of overqualification as well as their relation to family background is reviewed.
### 2.1 Ability and skills
Skill heterogeneities among workers with the same educational background are likely since human capital also comprises ability and skills that are not acquired during education. Workers could compensate a lack in ability and skills with a higher educational attainment in order to meet their jobs’ requirements (Korpi and Tåhlin 2009). Several studies find that individuals with relatively low ability have a higher probability to be overqualified (Chevalier and Lindley 2009). In general, these studies consistently suggest that cognitive skills are an important determinant of overqualification (Green et al. 1999; Quintini 2011). In Germany, individuals with worse school leaving grades or university grades face a higher risk of being overqualified (Büchel and Pollmann-Schult 2004; Fehse and Kerst 2007). Although non-cognitive skills have been found to predict various labour market outcomes (Heckman et al. 2006), studies focusing on non-cognitive skills as determinants of overqualification are scarce. Blázquez and Budría (2012) show that non-cognitive skills significantly reduce the probability of becoming overqualified in Germany. In contrast, Sohn (2010) finds no significant effect for the US.
Family background is a crucial determinant of an individual’s ability and skills (Feinstein 2003). Several studies find that cognitive skills of parents and their offspring in adulthood are significantly correlated (Anger and Heineck 2010; Björklund et al. 2010; Black et al. 2009). The same holds for the intergenerational transmission of non-cognitive skills within families (Anger 2012; Grönqvist et al. 2011). The amount of financial resources invested in an individual’s human capital is also likely to depend on the social origin (Bourdieu 1983).
Social differences in (innate) ability and skills could maintain a correlation between social origin and overqualification since the probability of being mismatched seems to be affected by cognitive skills and non-cognitive skills.
### 2.2 Study characteristics
The risk of overqualification has been found to be related to the characteristics of the individual’s education. For university graduates, the overqualification rates differ strongly across fields of study (Dolton and Vignoles 2000; Green and McIntosh 2007). Klein (2011) provides evidence that the occupational specificity of a field of study reduces the risk of overqualification. In Germany, the lowest rates of overqualification are observed for the subjects Medicine, Law, and Teaching (Berlingieri and Erdsiek 2012). As shown by Arcidiacono (2004), ability sorting and individual preferences are important drivers of subject choices. Differences in overqualification rates across subjects, therefore, might arise due to self-selection and are not interpretable in a causal manner (Berlingieri and Zierahn 2014). The risk of overqualification also differs across educational institutions. The quality or prestige of the university a worker graduated from has been found to affect the risk of overqualification (Robst 1995; McGuinness 2003). In Germany, individuals who obtained the university entrance certificate can choose between two tracks of tertiary education. They can either enrol at a traditional university or at a university of applied sciences. In general, traditional universities are academically more demanding than the practically oriented study programmes at universities of applied sciences. At the early stage of the career cycle, German graduates from universities of applied sciences face a higher risk of overqualification than graduates from universities (Klein 2011).
Many studies provide empirical evidence that family background is crucially important for educational choices such as the decision to enrol in tertiary education (Lucas 2001). Recently, a growing number of sociological studies analyse how social origin affects the choice of field of study. The results indicate that the subject choice is related to the family’s socioeconomic status and parental occupations (Becker et al. 2010; Jonsson et al. 2009). In Germany, the offspring from high status families more often enrol in subjects promising high levels of prestige or economic payoff such as Medicine or Law (Lörz 2012). Social differences tend to be less pronounced in the fields of Engineering or Business & Economics. The literature has pointed out several pathways for the family background effects on subject choice. In order to avoid downward social mobility, members of the privileged group might be more inclined to choose more promising subjects. Subject choices are also based on considerations on costs and benefits which might depend on the social origin. Furthermore, differences in the school leaving examination grades might contribute to the social stratification in fields of study. Enrollment in some prestigious subjects is restricted by the requirement of school grades better than a certain threshold. In addition, some studies focus on the relevance of occupational reproduction in the context of subject choices (Jonsson et al. 2009; Van de Werfhorst and Luijkx 2010). The intergenerational transmission of occupation-specific knowledge seems to affect the offspring’s preferences and interests which are crucial for the subject choice. Family background also might influence the decision whether to enrol in traditional universities or in the more practically oriented universities of applied sciences. Studying at a university of applied sciences might be more appealing for members of the less privileged group for the same reasons that affect the subject choice (Reimer and Pollak 2009). The quality or prestige of the chosen university also might depend on the available financial capital transmitted within families.
Since the risk of overqualification strongly differs across subjects and university type, social stratification in the study programme characteristics might contribute to the association between social origin and overqualification.
### 2.3 Capital transmitted within families
A social gap in the risk of overqualification could also be mediated by the different kinds of capital transmitted within families. The process of finding a job could be directly influenced through the social capital of the parents. Based on their social networks, parents may provide contacts to potential employers. These social connections could be more advantageous for graduates from high status families. For instance, Corak and Piraino (2011) provide evidence for the intergenerational transmission of employers between Canadian fathers and their sons. The probability that sons are working for the same employer as their father increases with the father’s earnings and is particularly high among the top income families. Weiss and Klein (2011) analyse how the probability of overqualification is affected by different types of social networks that helped graduates to find their job. Graduates who found their jobs through the agency of their professors or previous internships during the study programme obtain a lower risk of overqualification. In contrast, finding the job through the agency of parents or friends is associated with a higher probability of overqualification.
Social differences in aspiration might affect occupational choices after tertiary education has been completed. Graduates from high status families might try to prevent downward mobility by only accepting jobs requiring tertiary education. In contrast, graduates from low status families already reached the goal of social advancement by obtaining a tertiary degree. They might be less motivated to be in leading positions or to get a high status job (Jacob and Klein 2013). Due to occupational reproduction, graduates might also end up in similar occupations as their parents. For graduates from low status families these jobs are less likely to require a tertiary degree.
### 2.4 Discrimination
Graduates from low status families could be prevented from accessing adequate jobs due to discrimination. A crucial source for discrimination is favouritism which occurs if persons are favoured not because of relevant characteristics but rather because of being a member of a preferred group. In the context of this study, favouritism would occur if recruiters are less likely to pick graduates from low status families out of a group of equally eligible candidates for a high-skilled job. It is important to point out that this behaviour only pictures discrimination if the recruiter’s decision is only based on favouring members of high status families but is not due to productivity signals associated with family background. Potential employers could incorporate family background into their selection process of new workers as a signal related to productivity (Jacob and Klein 2013). As pointed out by Erikson and Jonsson (1998), the difference between favouritism and the productivity mechanism is rather subtle.
## 3 Data
### 3.1 Data set
Overqualification is the main outcome variable in this analysis. I employ a subjective measure for overqualification that is based on self-assessments of the graduates. Graduates were directly asked whether their job usually requires a tertiary education. They are defined to be overqualified if they indicate that their job usually does not require a tertiary degree. Since this measure relies on the workers’ self-assessment, it is sensitive to potential differences in the individuals’ perception of job requirements (Barone and Ortiz 2011). Estimates of the family background effect on overqualification would be biased if actually identical job requirements were assessed differently by graduates who originate from either low or high status families. Therefore, I have to assume that the assessment of job requirements does not systematically differ between both groups of graduates. As pointed out in the literature, the subjective measure of overqualification has the main advantage that it captures specific job characteristics that only the job holder can assess and, thus, is not based on information aggregated at any occupational level (Hartog 2000).2
The central explanatory variable of this study is the social origin of graduates which is measured in terms of parental education (PE). In particular, I use the information whether at least one parent has completed tertiary education. Graduates are divided into two groups: They either originate from a family with at least one parent holding a tertiary degree (high PE) or from a family with neither of the parents holding a tertiary degree (low PE). An education-based measure of family background is likely to be correlated with other, unobserved aspects of social origin, such as parents’ ability, preferences or support. Therefore, parental education serves as a general proxy for the educational, social and economic background of graduates.
The aim of this study is to uncover which channels contribute to the social gap in the risk of overqualification. Employing a rich data set, I thus include the following proxy variables for the aforementioned potential mediators. The potential mediating channel of social differences in ability and skills is accounted for by including school leaving examination grades and university grades.3 Grades can take decimal values within the range of 1 to 4, with higher grades indicating better achievements. Since the procedures of the school leaving examination differ across the 16 federal states in Germany, school grades are standardised within federal states. University grades are standardised within fields of study and university types in order to account for differences in the distribution of grades.
Differences in the study programme characteristics are observed in terms of field of study, university type and study duration. The subject groups Medicine & Law, and Teaching can solely be studied at universities, whereas the remaining subjects can be studied at either universities or universities of applied sciences. The latter subjects are divided into three groups, namely Science, Technology, Engineering, and Mathematics (STEM subjects), Business & Economics, and Social & Cultural Sciences. Dummy variables are generated for each combination of subject group and type of university (university vs. university of applied sciences). Study duration (in semesters) is standardised within subjects and university types since average study durations vary across subjects and university types.
Information on job search channels is employed to account for differences in social capital. Respondents indicated whether they found their current job through the guidance of their parents or friends. If high-skilled parents have better connections to potential employers, this search channel could be more profitable for graduates from high PE families. Further search channels include connections that have been established during a previous internship or other jobs the graduate has had before or during the study.
Financial capital is a crucial part of the properties that characterise high status families. Unfortunately, the data set does not contain a direct question concerning a family’s financial capital such as parental earnings. Therefore, a set of 3 proxy variables are employed. First, I include the information to what extent graduates financed their costs of living during the study by own work or by parental support. Although the observed shares result from graduates’ choices, they could proxy for parental financial capital. The offspring from poorer families, for instance, are expected to be more often constrained to work during the study. This is also the rationale of the second proxy variable, where respondents indicate if their job during study was related or unrelated to their subject. If working is necessary for financing the study, it may be more likely that jobs are taken that are unrelated to the subject. The third proxy for financial capital covers information on the graduates’ regional mobility. The respondents indicate the distance between working place and native place. The rationale of this proxy is that moving or commuting over a long distance could be encouraged by parental financial support.
Finally, I include a gender dummy and control variables for age, marriage, and parenthood at the time of the survey (one year after graduation).
### 3.2 Descriptive statistics
Descriptive statistics for the estimation sample are provided in Table 1. One year after graduation 20 % of the respondents are overqualified, i.e. they hold jobs that usually do not require a tertiary education. 46 % of the graduates originate from a high PE family, i.e. at least one parent holds a tertiary degree. With a share of 25 %, most respondents graduated in STEM subjects at traditional universities.
Tab. 1
Descriptive Statistics
Mean
SD
Min
Max
Overqualification
0.201
0.401
0
1
High PEa
0.461
0.499
0
1
(Pre-)Study characteristics:
Vocational education
0.373
0.484
0
1
0.000
0.998
$$-$$3.16
2.53
0.000
0.998
$$-$$4.12
2.42
Duration of studyc
0.000
0.998
$$-$$2.54
6.29
Univ. of applied sciences (UAS)
0.253
0.435
0
1
University types, Subjects:
Univ.: Medicine & Law
0.111
0.314
0
1
Univ.: Teaching
0.112
0.315
0
1
Univ.: STEM Subjects
0.247
0.431
0
1
UAS: STEM Subjects
0.172
0.377
0
1
Univ.: Bus & Econ
0.145
0.352
0
1
UAS: Bus & Econ
0.046
0.209
0
1
Univ.: Soc & Cult Science
0.133
0.340
0
1
UAS: Soc & Cult Science
0.035
0.184
0
1
Job found through:
Agency of parents/friends
0.077
0.267
0
1
Job before studying
0.048
0.214
0
1
Job while studying
0.126
0.332
0
1
Internship
0.162
0.369
0
1
Worked during study:
Yes: related to subject
0.569
0.495
0
1
Yes: not related to subject
0.189
0.392
0
1
Not worked during study
0.242
0.428
0
1
Study was financed by:
Own work (in %)
28.453
22.538
0
99
Parental support (in %)
44.766
31.489
0
99
Distance work and native place:
Less than 50 km
0.470
0.499
0
1
Between 50 km and 100 km
0.146
0.353
0
1
More than 100 km
0.385
0.487
0
1
Improve career prospects:
Commitment to the job
0.433
0.496
0
1
0.313
0.464
0
1
Established social networks
0.406
0.491
0
1
Have been mobile
0.300
0.458
0
1
0.415
0.493
0
1
Future goals:
Above-average performance
0.685
0.465
0
1
Fully exploit own potential
0.801
0.399
0
1
0.547
0.498
0
1
Observations
3706
a High Parental Education (PE) takes value one if at least one parent has a tertiary degree and zero otherwise b Standardised within federal states c Standardised within subjects and university types. Source: HIS-Graduate Panel 1997.
Table 2 presents the differences in the mean values depending on the family background. Column 1 presents the means for graduates from low PE families, whose parents do not hold a tertiary degree, and column 2 presents the means for graduates from high PE families. A share of 16.1 % of the high PE graduates is overqualified whereas 23.5 % of the graduates from low PE families are overqualified.5 Column 3 shows that the mean difference of 7.4 percentage points is significantly different from zero at the 1 percent level.
Tab. 2
Descriptive Statistics by Family Background
Low PE
High PE
Mean
Mean
Diff.
Dependent variable:
Overqualification
0.235
0.161
0.074 $${}^{***}$$
(Pre-)Study characteristics:
Vocational education
0.468
0.263
0.205 $${}^{***}$$
$$-$$ 0.116
0.136
$$-$$ 0.252 $${}^{***}$$
$$-$$ 0.038
0.044
$$-$$ 0.082 $${}^{**}$$
Duration of study b
$$-$$ 0.009
0.011
$$-$$ 0.020
Univ. of applied sciences (UAS)
0.342
0.148
0.194 $${}^{***}$$
University types, Subjects:
Univ.: Medicine & Law
0.078
0.149
$$-$$ 0.071 $${}^{***}$$
Univ.: Teaching
0.101
0.124
$$-$$ 0.023 $${}^{**}$$
Univ.: STEM Subjects
0.207
0.293
$$-$$ 0.086 $${}^{***}$$
UAS: STEM Subjects
0.237
0.095
0.143 $${}^{***}$$
Univ.: Bus & Econ
0.150
0.139
0.012
UAS: Bus & Econ
0.063
0.026
0.037 $${}^{***}$$
Univ.: Soc & Cult Science
0.121
0.147
$$-$$ 0.026 $${}^{**}$$
UAS: Soc & Cult Science
0.042
0.028
0.014 $${}^{**}$$
Job found through:
Agency of parents/friends
0.076
0.079
$$-$$ 0.003
Job before studying
0.063
0.030
0.033 $${}^{***}$$
Job while studying
0.136
0.115
0.020 $${}^{*}$$
Internship
0.160
0.164
$$-$$ 0.004
Worked during study:
Yes: related to subject
0.560
0.580
$$-$$ 0.020
Yes: not related to subject
0.223
0.150
0.073 $${}^{***}$$
Not worked during study
0.217
0.270
$$-$$ 0.053 $${}^{***}$$
Study was financed by:
Own work (in %)
32.243
24.025
8.218 $${}^{***}$$
Parental support (in %)
33.948
57.407
$$-$$ 23.46 $${}^{***}$$
Distance work and native place:
Less than 50 km
0.492
0.444
0.048 $${}^{***}$$
Between 50 km and 100 km
0.162
0.126
0.036 $${}^{***}$$
More than 100 km
0.346
0.430
$$-$$ 0.084 $${}^{***}$$
Improve career prospects:
Commitment to the job
0.435
0.431
0.004
0.254
0.381
$$-$$ 0.127 $${}^{***}$$
Established social networks
0.393
0.422
$$-$$ 0.030 $${}^{*}$$
Have been mobile
0.295
0.305
$$-$$ 0.011
0.409
0.422
$$-$$ 0.013
Future goals
Above-average performance
0.686
0.685
0.001
Fully exploit own potential
0.798
0.804
$$-$$ 0.006
0.553
0.541
0.013
Observations
1997
1709
3706
a Standardised within federal states b Standardised within subjects and university types; Significant at 1 % $${}^{***}$$, significant at 5 % $${}^{**}$$, significant at 10 % $${}^{*}$$. Source: HIS-Graduate Panel 1997.
The job search channels differ in some aspects. Low PE graduates more often found their job through jobs they had before studying (6 %) or during the study (14 %). This finding corresponds to the fact that the share of respondents who completed a vocational education before entering the study programme is higher among low PE graduates. There are no significant differences in the share of graduates finding a job through the agency of parents/friends (8 %) or an internship (16 %).
Concerning the proxies for the families’ financial capital, I find that during the study programme low PE graduates more often worked in jobs not related to their subject (22 %). Low PE graduates financed a share of 32 % of their costs of living during the study programme by own work. In contrast, earnings from own work covered only 24 % for high PE graduates. The share of costs of living financed by parental support was significantly higher for high PE graduates (57 %) than for low PE graduates (34 %). High PE graduates have been more mobile than low PE graduates since they are more likely to work more than 100 kilometers away from the native place (43 %).
I find little evidence for social differences in the proxy variables for career orientation and aspiration. For instance, 43 % of both groups of graduates indicated that they have shown high commitment to the job in order to improve career prospects and 55 % indicated that they have the future goal of filling a leading position. However, the share of graduates who gained experiences abroad is significantly higher among high PE graduates (38 %) than among low PE graduates (25 %).
## 4 Methodology
As shown in the descriptive statistics, overqualification is more prevalent among graduates from low PE families than among graduates from high PE families. The empirical analysis now focuses on the question which of the aforementioned pathways contribute to the social overqualification gap.
In a first step, it is tested whether the family background effect is robust against the inclusion of the potential mediating variables. Conducting probit regressions, the effects of family background and the mediating factors on the probability to be overqualified one year after graduation are estimated. For graduate $$i$$, the relationship is specified as:
$$\Pr[\mathit{Overqualification}_{i}=1|\mathit{High\_PE}_{i},\mathbf{X_{i}}]=\Phi(\alpha+\beta_{\mathrm{High\_PE}}High\_PE_{i}+\boldsymbol{\beta}\mathbf{{}_{X}}\mathbf{X_{i}})$$
(1)
with $$\Phi(\cdot)$$ representing the cumulative normal distribution function. The binary variable Overqualification takes the value one if a graduate works in a job that does not require a tertiary education and zero otherwise. Family background is measured by the binary variable High PE taking the value one if at least one parent holds a tertiary degree and zero if parents do not hold a tertiary degree. All aforementioned control variables are included in matrix $$\mathbf{X}$$.
In the second step, a decomposition analysis is applied to reveal how differences in observable characteristics contribute to the social overqualification gap. For this purpose, I employ the Blinder–Oaxaca decomposition method for mean outcome differences (Blinder 1973; Oaxaca 1973). In a linear model, the raw differential in the continuous outcome variable Y between two groups L and H can be expressed in two ways:
$$\overline{Y}_{L}-\overline{Y}_{H}=(\overline{X}_{L}-\overline{X}_{H})\beta_{L}+\overline{X}_{H}(\beta_{L}-\beta_{H}),$$
(2)
$$\overline{Y}_{L}-\overline{Y}_{H}=(\overline{X}_{L}-\overline{X}_{H})\beta_{H}+\overline{X}_{L}(\beta_{L}-\beta_{H}),$$
(3)
where $$\overline{X}_{j}$$ is a row vector comprising average values of the independent variables and $$\beta_{j}$$ is a vector of coefficient estimates obtained by OLS regressions for group $$j=L,H$$.7 The first part on the right hand side of both equations is the explained part of the raw gap that can be attributed to differences in observable characteristics, i.e. the endowments effects. The second term on the right hand side indicates which share of the gap is due to group differences in the estimated coefficients. This unexplained part also picks up the share of the raw differential due to differences in unobservable characteristics, i.e. unobserved heterogeneity between groups L and H. The unexplained part can thus not be interpreted as a single measure for discrimination such that the same bundle of characteristics is less valuable for one group only because of group membership.
Equations (2) and (3) differ in terms of the weights used for the evaluation of the endowments effect. The selection of the weighting scheme hinges on the expectation whether members of group L or members of group H are being discriminated. Optimally, the nondiscriminatory coefficients should be used but these are unknown and have to be approximated. If it is assumed, for instance, that group H is being discriminated, the endowments effect is evaluated by the coefficients of group L ($$\beta_{L}$$) (Eq. 2).8
Since the outcome variable in the present study is binary, I employ the methodology by Yun (2004) enabling Blinder–Oaxaca decompositions for non-linear models. Using this methodology, the social overqualification gap can be decomposed into the endowments effect and coefficients effect at the aggregate level. Furthermore, the methodology is suited to indicate the contribution of each variable to the raw differential, i.e. to compute the detailed decomposition. I will use the detailed decomposition to analyse which pathways are particularly relevant for generating the social overqualification gap.
## 5 Results
### 5.1 Probit results
Results from probit estimations of overqualification on family background and relevant control variables are provided in Table 3. The marginal effect of originating from a high PE family is significant if socio-demographic controls and proxies for ability are included in the probit model (specification 1). The likelihood of being overqualified is 6.2 percentage points lower for graduates whose parents obtained higher education than for graduates from low PE families. Better school leaving examination grades and university grades significantly reduce the probability of being overqualified. Since university grades are standardised within subjects and university types, the results suggest that the probability to be overqualified reduces by 5 percentage points if university grades increase by one standard deviation.
Tab. 3
Probit Regressions, Overqualification
Dependent variable: Overqualification
(1)
(2)
(3)
High PE a
$$-$$ 0.062 $${}^{***}$$
(0.013)
$$-$$ 0.041 $${}^{***}$$
(0.013)
$$-$$ 0.033 $${}^{**}$$
(0.014)
(Pre-)Study characteristics:
Vocational education
0.021
(0.017)
0.011
(0.017)
$$-$$ 0.023 $${}^{***}$$
(0.007)
$$-$$ 0.010
(0.007)
$$-$$ 0.004
(0.007)
$$-$$ 0.050 $${}^{***}$$
(0.007)
$$-$$ 0.053 $${}^{***}$$
(0.007)
$$-$$ 0.041 $${}^{***}$$
(0.007)
Duration of study
0.017 $${}^{**}$$
(0.007)
0.014 $${}^{**}$$
(0.007)
University types, Subjects: b
Univ.: Medicine & Law
$$-$$ 0.205 $${}^{***}$$
(0.008)
$$-$$ 0.194 $${}^{***}$$
(0.008)
Univ.: Teaching
$$-$$ 0.136 $${}^{***}$$
(0.013)
$$-$$ 0.134 $${}^{***}$$
(0.012)
Univ.: STEM Subjects
$$-$$ 0.164 $${}^{***}$$
(0.014)
$$-$$ 0.146 $${}^{***}$$
(0.014)
UAS: STEM Subjects
$$-$$ 0.103 $${}^{***}$$
(0.017)
$$-$$ 0.091 $${}^{***}$$
(0.017)
Univ.: Bus & Econ
$$-$$ 0.038 $${}^{**}$$
(0.019)
$$-$$ 0.020
(0.020)
UAS: Bus & Econ
0.019
(0.032)
0.031
(0.033)
UAS: Soc & Cult Science
$$-$$ 0.085 $${}^{***}$$
(0.023)
$$-$$ 0.078 $${}^{***}$$
(0.023)
Job found through:
Agency of parents/friends
0.143 $${}^{***}$$
(0.029)
Job before studying
0.109 $${}^{***}$$
(0.035)
Job while studying
0.086 $${}^{***}$$
(0.022)
Internship
$$-$$ 0.069 $${}^{***}$$
(0.015)
Worked during study: c
Yes: related to subject
$$-$$ 0.042 $${}^{**}$$
(0.018)
Yes: not related to subject
$$-$$ 0.012
(0.019)
Study was financed by:
Own work (in %)
0.001 $${}^{*}$$
(0.000)
Parental support (in %)
0.000
(0.000)
Distance work and native place: d
Between 50 km and 100 km
$$-$$ 0.034 $${}^{**}$$
(0.016)
More than 100 km
$$-$$ 0.051 $${}^{***}$$
(0.014)
Improve career prospects:
Commitment to the job
$$-$$ 0.031 $${}^{**}$$
(0.013)
$$-$$ 0.035 $${}^{***}$$
(0.014)
Established social networks
0.006
(0.013)
Have been mobile
$$-$$ 0.027 $${}^{*}$$
(0.014)
0.011
(0.013)
Future goals:
Above-average performance
$$-$$ 0.029 $${}^{**}$$
(0.014)
Fully exploit own potential
0.019
(0.015)
$$-$$ 0.002
(0.013)
Socio-demographics e
Yes
Yes
Yes
Observations
3706
3706
3706
Pseudo $$R^{2}$$
0.047
0.126
0.166
Probit estimations; Marginal effects (at the average); Standard errors in parentheses a Takes value one if at least one parent has a tertiary degree and zero otherwise b Reference: Univ: Social & Cultural Sciences c Reference: Not worked during study d Reference: Less than 50 km e Socio-demographic controls include age and dummies for gender, being married, and having children; Significant at 1 % $${}^{***}$$, significant at 5 % $${}^{**}$$, significant at 10 % $${}^{*}$$.
In specification 2, further study characteristics are included in the model. The coefficient of family background decreases but remains highly significant. While the effect of university grades hardly changes, the effect of school grades diminishes. The favourable effect of good school grades on the risk of overqualification, therefore, might work through the selection into subjects promising a good transition into the labour market. University grades seem to be more important to potential employers who might use this information as a signal for job related skills. Similarly, the significant and positive coefficient of standardised study duration could indicate that an above-average study duration sends a negative signal regarding a graduate’s ability or motivation. The incidence of overqualification is found to strongly differ across subjects. Compared to the reference group of Social & Cultural Sciences at traditional universities, graduates in Medicine & Law obtain a 20.5 percentage points lower probability to be overqualified. Only Business & Economics graduates from universities of applied sciences do not obtain a significantly lower probability of overqualification than the reference group. Due to self-selection into subjects, however, these effects can not be interpreted in a causal manner.
Specification 3 includes the full set of observable characteristics that could mediate the relationship between family background and overqualification. The family background effect reduces but remains significant. The results indicate that the probability to be overqualified is 3.3 percentage points lower for graduates from high PE families even if grades, study characteristics and the following mediating factors are accounted for.
Information on a graduate’s social capital is included in terms of job search channels. Finding the current job through the agency of parents/friends, a job before studying, or a job while studying increases the probability to be overqualified. Since jobs held before or during the study usually do not require tertiary education, these social networks seem to hamper the transition into a matching job. In contrast, social connections based on internships support a good start of the career. Finding a job through an internship is associated with a reduction in overqualification by 6.9 percentage points.
The financial capital of families is measured through working experience during the study, the parents’ financial support and regional mobility. Graduates who worked in a subject-related job during the study are significantly less likely to be overqualified than graduates who did not work during the study. No favourable effect is found for working in jobs unrelated to the subject. The probability to be overqualified increases with the share of costs of living during the study that was financed by own work. But no significant effect is found for the share that was covered by parental support. Regional mobility is related to a lower risk of overqualification. Graduates whose working place is more than 50 kilometers away from their native place are significantly less likely to be overqualified. Of course, this effect cannot be interpreted in a causal way since the decision to move or commute itself is probably determined by the job quality. With respect to the focus of the analysis, however, it could be relevant if social differences in the graduates’ regional mobility contribute to the overqualification gap.
Some of the proxies for career orientation and aspiration are significantly related to overqualification. The probability to be overqualified is roughly 3 percentage points lower for graduates who indicated that they showed commitment to the job, gained experiences abroad, or were regionally mobile in order to improve their career prospects. Moreover, the share of overqualification is 2.9 percentage points lower among graduates who have the future goal to perform above-average in their job.
The robust family background effect in specification 3 could be the result of both unobserved heterogeneity and discrimination. An important source for unobserved heterogeneity might be that the available proxy variables measure the mediating factors for family background effects imprecisely. For instance, school grades and university grades are used as proxies for ability and skills. However, social differences in specific skills like numeracy or literacy are not observed. A further important component of an individual’s human capital are non-cognitive skills which predict various labour market outcomes. The literature on human capital acquisition generally concludes that the offspring of wealthy families have higher non-cognitive skills. Therefore, including a proxy for non-cognitive skills could reduce the conditional correlation between social origin and overqualification. The present study, however, focuses on a highly selective group of individuals who completed tertiary education. Whether social differences in non-cognitive skills exist among the highly educated respondents in the sample is unclear. Graduates originating from low PE families might only have been able to complete higher education because they compensated the less favourable parental support by higher non-cognitive skills.
Proxy variables for the different kinds of capital transmitted within families might also be imprecise. For instance, I cannot observe whether graduates accepted a job offer because of financial constraints due to low financial capital of the parents. Furthermore, I cannot control for social differences in cultural capital. Graduates from high PE families might be more familiar with hiring procedures and the functionality of the high-skilled labour market. Graduates might also differ in terms of transmitted preferences and opinions that lower the risk of overqualification. Finally, it is likely that my measures for career orientation and aspiration cannot account for the entirety of this phenomena. For instance, some career choices might be the result of unconscious decision processes related to innate aspiration.
The family background effect could also be attributed to preferences of potential employers. Recruiters could use the family background as a signal for ability and skills. Furthermore, they could value individual characteristics differently depending on social origin of the applicants. The latter case implies discrimination if recruiters favour applicants from high PE families without any other reason than group membership. As a consequence, graduates exhibiting the same characteristics could differ in the number and quality of jobs they get offered.
### 5.2 Decomposition results
Employing a decomposition analysis, individual characteristics are identified that mediate the effect of family background on the probability to be overqualified.9 In a first step, the group specific coefficients are estimated by running probit regressions separately for graduates from low PE families (specification 1) and high PE families (specification 2) as presented in Table 4. The results show similar effects of university grades, study characteristics and job search channels for both groups of graduates. The significant increase in the overqualification risk due to finding the job through the guidance of parents/friends is not statistically different between low PE graduates (13 percentage points) and high PE graduates (15 percentage points).
Holding a subject-related job during study and financing the study through own work is significantly correlated with overqualification solely for low PE graduates. Gaining experiences abroad reduces the risk of overqualification for both groups, while the effects of the remaining strategies to improve career prospects depend on social origin. High PE graduates who have the future goal of above-average performance obtain a lower overqualification risk, while overqualification is more likely among those who plan to fully exploit their own potential. The latter effect may result from reversed simultaneity because overqualified workers might set this future goal as a reaction to the current underutilization of skills.
Tab. 4
Probit Regressions by Family Background, Overqualification
Dependent variable: Overqualification
Low PE
High PE
(1)
(2)
(Pre-)Study characteristics:
Vocational education
0.003
(0.025)
0.019
(0.022)
$$-$$ 0.012
(0.011)
0.006
(0.009)
$$-$$ 0.041 $${}^{***}$$
(0.010)
$$-$$ 0.037 $${}^{***}$$
(0.008)
Duration of study
0.020 $${}^{*}$$
(0.011)
0.007
(0.009)
University types, Subjects: a
Univ.: Medicine & Law
$$-$$ 0.216 $${}^{***}$$
(0.013)
$$-$$ 0.163 $${}^{***}$$
(0.012)
Univ.: Teaching
$$-$$ 0.144 $${}^{***}$$
(0.022)
$$-$$ 0.111 $${}^{***}$$
(0.012)
Univ.: STEM Subjects
$$-$$ 0.147 $${}^{***}$$
(0.024)
$$-$$ 0.131 $${}^{***}$$
(0.017)
UAS: STEM Subjects
$$-$$ 0.081 $${}^{***}$$
(0.030)
$$-$$ 0.086 $${}^{***}$$
(0.016)
Univ.: Bus & Econ
0.024
(0.035)
$$-$$ 0.045 $${}^{**}$$
(0.020)
UAS: Bus & Econ
0.085
(0.052)
$$-$$ 0.025
(0.035)
UAS: Soc & Cult Science
$$-$$ 0.117 $${}^{***}$$
(0.032)
$$-$$ 0.021
(0.036)
Job found through:
Agency of parents/friends
0.129 $${}^{***}$$
(0.041)
0.151 $${}^{***}$$
(0.041)
Job before studying
0.086 $${}^{*}$$
(0.045)
0.175 $${}^{***}$$
(0.065)
Job while studying
0.102 $${}^{***}$$
(0.033)
0.070 $${}^{**}$$
(0.029)
Internship
$$-$$ 0.088 $${}^{***}$$
(0.024)
$$-$$ 0.050 $${}^{***}$$
(0.018)
Worked during study: b
Yes: related to subject
$$-$$ 0.081 $${}^{***}$$
(0.027)
$$-$$ 0.001
(0.021)
Yes: not related to subject
$$-$$ 0.043
(0.028)
0.028
(0.028)
Study was financed by:
Own work (in %)
0.001 $${}^{**}$$
(0.000)
$$-$$ 0.000
(0.000)
Parental support (in %)
0.000
(0.000)
$$-$$ 0.000
(0.000)
Distance work and native place: c
Between 50 km and 100 km
$$-$$ 0.073 $${}^{***}$$
(0.022)
0.017
(0.025)
More than 100 km
$$-$$ 0.073 $${}^{***}$$
(0.021)
$$-$$ 0.035 $${}^{**}$$
(0.017)
Improve career prospects:
Commitment to the job
$$-$$ 0.016
(0.020)
$$-$$ 0.041 $${}^{**}$$
(0.016)
$$-$$ 0.038 $${}^{*}$$
(0.022)
$$-$$ 0.030 $${}^{*}$$
(0.016)
Established social networks
$$-$$ 0.012
(0.020)
0.030 $${}^{*}$$
(0.016)
Have been mobile
$$-$$ 0.044 $${}^{**}$$
(0.022)
$$-$$ 0.009
(0.018)
0.008
(0.020)
0.017
(0.016)
Future goals:
Above-average performance
$$-$$ 0.023
(0.021)
$$-$$ 0.041 $${}^{**}$$
(0.018)
Fully exploit own potential
0.001
(0.024)
0.034 $${}^{*}$$
(0.018)
0.007
(0.020)
$$-$$ 0.013
(0.017)
Socio-demographics d
Yes
Yes
Observations
1997
1709
Pseudo $$R^{2}$$
0.150
0.202
Probit estimations; Marginal effects (at the average); Standard errors in parentheses a Reference: Univ: Social & Cultural Sciences b Reference: Not worked during study c Reference: Less than 50 km d Socio-demographic controls include age and dummies for gender, being married, and having children; Significant at 1 % $${}^{***}$$, significant at 5 % $${}^{**}$$, significant at 10 % $${}^{*}$$.
Based on the presented auxiliary probit regressions, the social overqualification gap can be decomposed into two parts that are explained or unexplained by differences in observable characteristics. The explained part, i.e. the endowments effect, can be either evaluated with the coefficients estimated in specification (1) or (2) of Table 4. The results of the non-linear Blinder–Oaxaca decomposition when the low PE graduate coefficients are used for evaluating the endowments effect are presented in Table 5. A share of 23.5 % of the graduates from low PE families are overqualified, while only 16.1 % of the graduates from high PE families are overqualified. The difference in these percentages, i.e. the total overqualification gap, amounts to 7.4 percentage points. A share of 60.6 % of the overqualification gap can be attributed to the fact that graduates differ in observable characteristics depending on family background. This endowments effect can be interpreted in the following way: If high PE graduates had the same average observable characteristics as low PE graduates, the overqualification gap would be reduced by 4.5 percentage points.
Tab. 5
Decomposition of the Overqualification Gap, Weighted by Coefficients of Low PE Graduates ($$\beta_{L}$$)
Coef.
Std. Err.
$$P> |z|$$
% of Total gap
% of Explained part
Low PE
0.235
0.009
0.000
High PE
0.161
0.009
0.000
Total overqualification gap
0.074
0.013
0.000
Explained part
0.045
0.009
0.000
60.6
Unexplained part
0.029
0.013
0.026
39.4
Contribution to explained part
Vocational education
0.001
0.004
0.893
1.2
0.002
0.002
0.280
5.4
0.003
0.001
0.035
6.1
Study duration
0.000
0.001
0.556
$$-$$ 0.7
University types, Subjects
0.030
0.006
0.000
66.4
How job was found
0.004
0.002
0.051
8.1
Worked during study
$$-$$0.001
0.002
0.442
$$-$$ 3.0
Financing of study
0.000
0.007
0.983
$$-$$ 0.3
Dist work, native place
0.003
0.002
0.119
6.4
Improve career prospects
0.005
0.002
0.063
10.2
Future goals
0.000
0.000
0.885
0.1
Socio-demographics
0.000
0.003
0.986
0.1
Probit decomposition computed in Stata employing the procedure by Jann (2008); Explained part evaluated by coefficients of graduates from low PE families.
In order to identify through which pathways family background affects the risk of overqualification, I carry out a detailed decomposition of the endowments effect. Social differences in university grades explain a significant share of 6.1 % of the endowments effect. This result is in line with the previous findings that university grades are better among graduates from high PE families and that better grades reduce the risk of overqualification.
The most important contributor to the endowments effect is the choice of university type and subjects. A share of 66.4 % of the endowments effect can be attributed to social differences in these study characteristics. High PE graduates study more often at traditional universities and are more likely to choose subjects with a lower risk of overqualification. If graduates studied the same subjects at the same university type, the social overqualification gap would decrease by 3 percentage points.
Differences in the usage of job search channels significantly account for 8.1 % of the endowments effect. The main cause for this contribution is that low PE graduates more often find their job through a job they had before studying.10 The decomposition results do not indicate that graduates from high PE families obtain a lower risk of overqualification because they profit from parental networks in terms of job placement.
A significant part of the endowments effect can be attributed to differences in actions undertaken to improve career prospects. In particular, the higher share of high PE graduates who gained experiences abroad contributes to the endowments effect.
The previous decomposition results are strongly robust against changing the weighting scheme, i.e. using the coefficients for high PE graduates (Table 6). Social differences in university grades, subject choices, and job search channels remain significant contributors to the endowments effect. The overall contribution of the strategies to improve career prospects becomes insignificant but social differences in gaining experiences abroad remain a significant mediator. Since for high PE graduates the risk of overqualification decreases only if the distance between work and native place exceeds 100 kilometers, the regional mobility significantly contributes to the endowments effect if the high PE coefficients are used as weights. Independently of the weighting scheme, I find no indication that the other proxy variables accounting for financial support and aspiration significantly contribute to the endowments effect. This result might be driven by the lack of precision of the measures for these mediating factors.
Tab. 6
Decomposition of the Overqualification Gap, Weighted by Coefficients of High PE Graduates ($$\beta_{H}$$)
Coef.
Std. Err.
$$P> |z|$$
% of Total gap
% of Explained part
Low PE
0.235
0.009
0.000
High PE
0.161
0.009
0.000
Total overqualification gap
0.074
0.013
0.000
Explained part
0.044
0.011
0.000
58.9
Unexplained part
0.030
0.016
0.058
41.1
Contribution to explained part
Vocational education
0.004
0.004
0.364
9.2
$$-$$ 0.002
0.002
0.504
$$-$$ 3.5
0.003
0.001
0.032
7.2
Study duration
0.000
0.000
0.621
$$-$$ 0.3
University types, Subjects
0.023
0.007
0.000
53.0
How job was found
0.005
0.002
0.016
12.2
Worked during study
0.002
0.002
0.247
4.6
Financing of study
0.001
0.007
0.902
2.0
Dist work, native place
0.004
0.002
0.027
8.4
Improve career prospects
0.003
0.002
0.228
6.5
Future goals
0.000
0.001
0.579
$$-$$ 1.0
Socio-demographics
0.001
0.003
0.813
1.6
Probit decomposition computed in Stata employing the procedure by Jann (2008); Explained part evaluated by coefficients of graduates from high PE families.
Differences in endowments are an important force behind the overqualification gap but a substantial part of approximately 40 % of the gap remains unexplained.11 This unexplained part captures how differences in the coefficients of observable characteristics as well as group differences in unobserved characteristics contribute to the overqualification gap. The bulk of the unexplained part can be attributed to the group difference in the constant reflecting unobserved heterogeneity.12 Unobserved heterogeneity could arise because of missing proxies for relevant characteristics, such as non-cognitive skills, or because of imprecise measurement of mediators included in the analysis.
Discrimination could be a further reason for the significant unexplained part. Employers could value individual characteristics differently for graduates from high PE or low PE families. However, I find no indication that the overqualification gap widens because employers value the graduates’ characteristics differently. Differences in the group specific coefficients only play a minor role for the social overqualification gap in my analysis. Individual characteristics, such as university grades, seem to be equally evaluated by the labour market. However, it is possible that employers discriminate applicants on the basis of characteristics that I cannot observe with the data at hand.
## 6 Conclusion
This study finds that family background, as measured by parental education (PE), is a crucial determinant of overqualification at the start of graduates’ careers. One year after graduation, the unconditional overqualification gap between graduates from low PE families and high PE families amounts to 7.4 percentage points. The main aim of this study was to uncover which pathways mediate the link between family background and overqualification. In order to account for potential mediators, proxy variables for ability and skills, study characteristics, social capital, financial capital, and aspirations are included in the empirical analysis. Graduates are found to strongly differ in these potential mediators. The effect of family background is reduced but remains highly significant if the potential pathways are accounted for in a probit regression.
Employing a Blinder–Oaxaca approach, I show that roughly 60 % of the overqualification gap can be attributed to the fact that graduates differ in observable characteristics, i.e. the endowments effect. Concerning social differences in ability and skills, I find that differences in university grades significantly contribute to the overqualification gap. In contrast, social differences in school leaving examination grades are found to primarily affect overqualification through the selection into promising subjects. The most important mediator of the family background effect is the social difference in the choice of university type and subjects. This result points to the importance of the horizontal dimension of higher education in the context of parental influences on the risk of overqualification.
A substantial part of approximately 40 % of the overqualification gap remains unexplained by differences in observable mediators. Most of the unexplained part can be attributed to unobserved heterogeneity between graduates from low PE families and graduates from high PE families. An important source for unobserved heterogeneity might be that the proxy variables employed are imprecise measures of mediating factors. Other potentially important factors, such as non-cognitive skills, are not observed. The unexplained family background effect could also arise because of discrimination based on preferences of potential employers. Concerning the individual characteristics included in the present analysis, I find no indication that the overqualification gap widens because employers value characteristics differently. However, it is possible that employers discriminate applicants on the basis of characteristics that are not included in the analysis.
It is difficult to infer policy implications from the findings since it is crucial to disentangle the effect of parental education on overqualification from other potential effects of inherited ability or disposition. However, the result that the incidence of overqualification strongly differs across university types and subjects is striking. In particular, the subjects Medicine & Law, Teaching, and STEM at traditional universities exhibit considerably low overqualification rates. This finding holds for both types of graduates from low PE and high PE families. Since low PE graduates are significantly less likely to choose these subjects, I find that the social difference in the choice of university type and subject is the most relevant pathway for the social overqualification gap. Therefore, selective measures aiming to inform and motivate students from low PE families to choose promising subjects at traditional universities might reduce their overqualification risk, even though the estimated effects of studying in a particular subject might partly arise due to self-selection.
As this study focuses on graduates observed one year after graduation, no conclusions can be drawn on the correlation between family background and overqualification at later stages of the career cycle. Being overqualified shortly after labour market entry could send negative signals for potential employers in the future and shape long-run career prospects. It is a question for further research whether the persistence of overqualification depends on the social origin of graduates.
## Footnotes
1. 1.
Hochschul-Informations-System (HIS), Hannover (2007): HIS-Graduate Panel 1997. GESIS Data Archive, Köln. ZA4272 Data File Version 1.0.0, dx.doi.org/10.4232/1.4272.
2. 2.
In addition to the subjective indicator, two objective methods for measuring required education have been employed in the literature. First, the assignment of required education to occupations based on the evaluation of job analysts (JA approach). Second, the realized matches (RM) approach focusing on the distribution of educational qualifications possessed by workers within an occupation. The main drawback of the RM approach is that it measures the endogenous allocation of workers to jobs driven by demand and supply forces rather than the genuine job requirements. In contrast, the measures of the JA approach are based on the technology of the job yielding an objective evaluation of requirements. However, heterogeneities of jobs within occupational codes are ignored and JA indicators are not available for most countries, e.g. Germany. Hartog (2000) provides a detailed discussion on overqualification measures.
3. 3.
Although grades are surely an imperfect proxy for ability, previous research shows that cognitive as well as non-cognitive skills are relevant predictors of grades (Almlund et al. 2011; Poropat 2009).
4. 4.
The two items concerning experiences abroad and mobility may not only proxy for career orientation but also depend on the financial capital of the parents.
5. 5.
With the data at hand, little evidence for social differences concerning the selection into employment is found. At the time of the survey, 2.8 % of high PE graduates and 3.0 % of graduates from low PE families have been unemployed.
6. 6.
Social differences in university grades cannot be driven by self-selection into subjects with a higher level of average grades since university grades are standardised within university type and subject.
7. 7.
The auxiliary regressions for groups L and H are: $$Y_{L}=F(X_{L}\beta_{L})$$ and $$Y_{H}=F(X_{H}\beta_{H})$$
8. 8.
In many cases, it remains unclear which group is solely discriminated leading to an “index-number problem” (Oaxaca 1973). Since the choice of the weight influences the segmentation into the explained and unexplained part, researchers often present decomposition results for both weighting schemes or use coefficients from a pooled regression (Neumark 1988).
9. 9.
Decomposition results were computed in Stata employing the “Oaxaca” command (Jann 2008) incorporating the non-linear decomposition proposed by Yun (2004). As a robustness test, the analysis has also been conducted using the non-linear extension proposed by Fairlie (2005). The results are not qualitatively sensitive to the choice of methodology.
10. 10.
The detailed decomposition results presenting each variable separately are not shown in this paper but are available upon request.
11. 11.
The size of the unexplained part nearly equals the marginal family background effect estimated in the probit regression including all observable mediators.
12. 12.
The detailed decomposition of the unexplained part is available upon request.
## References
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http://link.springer.com/article/10.1007%2Fs10552-008-9159-0 | , Volume 19, Issue 9, pp 939-953
Date: 25 Apr 2008
# Physical activity, sedentary behavior, and the risk of colon and rectal cancer in the NIH-AARP Diet and Health Study
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## Abstract
### Objective
In order to prospectively investigate physical activity at varying intensities and sedentary behavior in relation to colorectal cancer.
### Methods
We considered 488,720 participants of the NIH-AARP Diet and Health Study who were aged 50–71 years at baseline in 1995–1996. Through 31 December, 2003, we identified 3,240 and 1,482 colorectal cancers among men and women, respectively. We estimated multivariable relative risks (RR) and 95% confidence intervals (CI) of colorectal cancer using Cox regression.
### Results
Engaging in exercise/sports five or more times per week compared to never or rarely exercising was associated with a reduced risk of colon cancer among men (= 0.001; RR = 0.79, 95% CI = 0.68–0.91) and a suggestive decrease in risk among women (= 0.376; RR = 0.85, 95% CI = 0.70–1.04). Engaging in exercise/sports was also associated with a decreased risk of rectal cancer in men (= 0.074; RR comparing extreme categories = 0.76, 95% CI = 0.61–0.94). In men, we observed inverse relations of both low intensity (= 0.017; RR = 0.81, 95% CI = 0.65–1.00 for ≥7 h/week) and moderate to vigorous intensity activity (= 0.037; RR = 0.82, 95% CI = 0.67–0.99 for ≥7 h/week) to colon cancer risk. In contrast, sedentary behavior (time spent watching television/videos) was positively associated with colon cancer (< 0.001; RR = 1.61, 95% CI = 1.14–2.27 for ≥9 h/day) among men. Similar, but less pronounced relations were observed in women.
### Conclusion
Engaging in physical activity of any intensity is associated with reductions in colon and rectal cancer risk. Conversely, time spent sedentary is associated with increased colon cancer risk. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.837601363658905, "perplexity": 6565.429639956676}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-14/segments/1427131302318.88/warc/CC-MAIN-20150323172142-00013-ip-10-168-14-71.ec2.internal.warc.gz"} |
http://mathoverflow.net/questions/70981/martingale-representation-theorem-for-levy-processes | # Martingale representation theorem for Levy processes
Is there an equivalent of martingale representation theorem for Levy processes in some form? I believe there is no such theorem in generality, but maybe there are some specific cases?
-
Have you taken a look at www2.imperial.ac.uk/~mdavis/docs/MARTREPBBL.PDF ? There seems to be some kind of result for jump processes. – Paul Tupper Jul 24 '11 at 3:29
Hi,
Here is a theorem that might answer your question (it is coming from Chesnay, Jeanblanc-Piqué and Yor's book "Mathematical Methods for Financial Markets").
It is theorem (11.2.8.1 page 621) here it is :
(edit note : be carefull as mentioned by G. Lowther there's a typo in the book regarding the domain of integration in the conditions over $\psi$ (defined hereafter) )
Let $X$ be an $R^d$ valued Lévy Process and $F^X$ its natural filtration. Let $M$ be an $F^X$-local Martingale. Then there exist an $R^d$-valued predictable process $\phi$ and an predictable function $\psi : R^+ \times \Omega \times R^d\to R$ such that :
-$\int_0^t \phi^i(s)^2ds <\infty$ almost surely
-$\int_0^t \int_{|x|> 1} |\psi(s,x)|ds\nu(dx) <\infty$ almost surely
-$\int_0^t \int_{|x|\le 1} \psi(s,x)^2ds\nu(dx) <\infty$ almost surely
and
$M_t=M_0+ \sum_{i=0}^d \int_0^t \phi^i(s)dW^i_s + \int_0^t \int_{R^d} \psi(s,x)\tilde{N}(ds,dx)$
Where $\tilde{N}(ds,dx)$ is the compensated measure of the Lévy process $X$ and $\nu$ the associated Lévy measure.
Moreover if $(M_t)$ is square integrable martingale then we have :
$E[(\int_0^t \phi^i(s)dW^i_s)^2]=E[\int_0^t \phi^i(s)^2ds]<\infty$
and
$E[(\int_0^t \int_{R^d} \psi(s,x)\tilde{N}(ds,dx))^2]=E[ \int_0^t ds \int_{R^d} \psi(s,x)^2\nu(dx)]<\infty$
and $\phi$ and $\psi$ are essentially unique.
The theorem is not proved in the book but there is a reference to the following parpers :
1/H. Kunita and S. Watanabe. On square integrable martingales. Nagoya J. Math., 30:209–245, 1967
2/H. Kunita. Representation of martingales with jumps and applications to mathematical finance. In H. Kunita, S. Watanabe, and Y. Takahashi, editors, Stochastic Analysis and Related Topics in Kyoto. In honour of Kiyosi Itô, Advanced studies in Pure mathematics, pages 209–233. Oxford University Press, 2004.
Regards
-
That sounds perfectly reasonable, except I think you might the inequalities $\vert x\vert\le1$ and $\vert x\vert > 1$ the wrong way round in the conditions for $\psi$. – George Lowther Jul 25 '11 at 17:37
Also, this answer does not seem to directly answer the question, although you can use the result you state to give a necessary and sufficient condition for a Levy process to satisfy the martingale representation property (satisfied by Brownian motion and by compensated Poisson processes, but not by general Levy processes). – George Lowther Jul 25 '11 at 17:40
@George Lowther : Hello George unless there's a typo in the book I quote I think I got it right. – The Bridge Jul 26 '11 at 10:05
@The Bridge: If that's what it says, then I think there must be a typo. The sum of squares of the jumps of a martingale is finite, $\sum\_{s\le t}(\Delta M_s)^2 < \infty$, because it has finite quadratic variation. That should correspond to $\int\_0^t\int\_{\vert x\vert\le1}\psi(s,x)^2ds\nu(dx) < \infty$. Also, the integrability of the martingale should correspond to $\int\_0^t\int\_{\vert x\vert > 1}\vert\psi(s,x)\vert ds\nu(dx) < \infty$. This is also required so that $\psi$ is $\tilde N$ integrable (almost-surely). – George Lowther Jul 26 '11 at 22:08
Actually, I think it does answer the question fully (once the possible typo is sorted), as it is the correct form of the martingale representation theorem for Levy processes. I was just thinking he meant representation as a stochastic integral wrt the original process, which is clearly not possible except for special cases. But he does say "in some form", and this seems to be the best form. – George Lowther Jul 26 '11 at 23:12 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9027352929115295, "perplexity": 228.56573426322868}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398474527.16/warc/CC-MAIN-20151124205434-00102-ip-10-71-132-137.ec2.internal.warc.gz"} |
https://www.mariakzurek.com/tags/central-exclusive-production/ | # Central Exclusive Production
## Diffractive interaction of protons at CDF
Central exclusive production processes are characterized by large regions in forward rapidity devoid of hadrons, and a centrally produced state, in our case pairs of charged mesons. This class of reactions measured at TeV energies has an important role in meson spectroscopy, favoring states having valence gluons, such as glueballs. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9397639036178589, "perplexity": 5966.744468543166}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590347432237.67/warc/CC-MAIN-20200603050448-20200603080448-00308.warc.gz"} |
https://pdglive.lbl.gov/DataBlock.action?node=M009M2&home=sumtabM | # ${{\boldsymbol \rho}{(770)}}$ MASS
We no longer list ${\mathit S}{\mathrm -wave}$ Breit-Wigner fits, or data with high combinatorial background.
# CHARGED ONLY, HADROPRODUCED INSPIRE search
VALUE (MeV) EVTS DOCUMENT ID TECN CHG COMMENT
$\bf{ 766.5 \pm1.1}$ OUR AVERAGE
$763.7$ $\pm3.2$
1997
CBAR ${{\overline{\mathit p}}}$ ${{\mathit n}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}$
$768$ $\pm9$
1991
EHS 400 ${{\mathit p}}{{\mathit p}}$
$767$ $\pm3$ 2935 1
1987
SPEC - 200 ${{\mathit \pi}^{-}}$ ${}^{}\mathrm {Cu}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{}^{}\mathrm {Cu}$
$761$ $\pm5$ 967 1
1987
SPEC - 200 ${{\mathit \pi}^{-}}$ ${}^{}\mathrm {Pb}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{}^{}\mathrm {Pb}$
$771$ $\pm4$
1986
SPEC + 202 ${{\mathit \pi}^{+}}$ ${}^{}\mathrm {A}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{0}}{}^{}\mathrm {A}$
$766$ $\pm7$ 6500 2
1973
OSPK - 5 ${{\mathit \pi}^{-}}{{\mathit p}}$
$766.8$ $\pm1.5$ 9650 3
1968
RVUE - 1.7$-$3.2 ${{\mathit \pi}^{-}}{{\mathit p}}$ , $\mathit t$ $<$10
$767$ $\pm6$ 900 1
1967
HBC - 4.2 ${{\mathit \pi}^{-}}{{\mathit p}}$ , $\mathit t$ $<$10
1 Mass errors enlarged by us to $\Gamma /\sqrt {\mathit N }$; see the note with the ${{\mathit K}^{*}{(892)}}$ mass.
2 Phase shift analysis. Systematic errors added corresponding to spread of different fits.
3 From fit of 3-parameter relativistic ${\mathit P}{\mathrm -wave}$ Breit-Wigner to total mass distribution. Includes BATON 1968 , MILLER 1967B, ALFF-STEINBERGER 1966 , HAGOPIAN 1966 , HAGOPIAN 1966B, JACOBS 1966B, JAMES 1966 , WEST 1966 , BLIEDEN 1965 and CARMONY 1964 .
References:
ABELE 1997
PL B391 191 High Mass ${{\mathit \rho}}$ Meson States from ${{\overline{\mathit p}}}{{\mathit d}}$ Annihilation at Rest into ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}{{\mathit p}}_{spect.}$
AGUILAR-BENITEZ 1991
ZPHY C50 405 Inclusive Particle Production in 400 ${\mathrm {GeV/}}\mathit c$ ${{\mathit p}}{{\mathit p}}$ Interactions
CAPRARO 1987
NP B288 659 The ${{\mathit \rho}{(770)}}$ Radiative Decay Width: A Measurement at 200 GeV
HUSTON 1986
PR D33 3199 Measurement of the Resonance Parameters and Radiative Width of the ${{\mathit \rho}{(770)}^{+}}$
BYERLY 1973
PR D7 637 ${{\mathit \rho}{(770)}^{-}}$ Production and Decay in the Reaction ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit p}}$ at 5 ${\mathrm {GeV/}}\mathit c$
PISUT 1968
NP B6 325 ${{\mathit \rho}}$ Meson Shape
EISNER 1967
PR 164 1699 ${{\mathit \pi}^{-}}{{\mathit p}}$ Two Prong Interactions at 4.16 ${\mathrm {GeV/}}\mathit c$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8425818085670471, "perplexity": 10725.003570429972}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178366477.52/warc/CC-MAIN-20210303073439-20210303103439-00613.warc.gz"} |
https://waseda.pure.elsevier.com/en/publications/experimental-investigation-of-loading-due-to-debris-dams-on-struc | Gabriella Mauti*, Jacob Stolle, Tomoyuki Takabatake, Ioan Nistor, Nils Goseberg, Abdolmajid Mohammadian
*Corresponding author for this work
Research output: Contribution to journalArticlepeer-review
1 Citation (Scopus)
## Abstract
The entrainment of debris in tsunami-induced floods and storm surges can result in their accumulation on structures, a phenomenon known as debris damming. Such dams can decrease the stability of the affected structures by increasing the area of the flow obstruction, resulting in increased resistance forces. The formation of debris dams can also result in upstream water level rise. This study investigated the influence of idealized debris dam geometry on induced loads and changes in the free surface surrounding a circular column in steady-state flow conditions. Additionally, it investigated the resistance force coefficient of the debris dams. Results show that the presence of debris dams results in a significant increase of loading on structures. The increase in the resistance force was up to 7.7 times greater than the resistance force acting on the column with no debris present. The resistance force coefficients and the change in water depth were functions of the relative dam height and the Froude number, while the porosity had an insignificant impact on the effective resistance force coefficients.
Original language English 04020029 Journal of Hydraulic Engineering 146 5 https://doi.org/10.1061/(ASCE)HY.1943-7900.0001731 Published - 2020 May 1
## ASJC Scopus subject areas
• Civil and Structural Engineering
• Water Science and Technology
• Mechanical Engineering
## Fingerprint
Dive into the research topics of 'Experimental Investigation of Loading due to Debris Dams on Structures'. Together they form a unique fingerprint. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8414083123207092, "perplexity": 4128.486948393763}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662584398.89/warc/CC-MAIN-20220525085552-20220525115552-00247.warc.gz"} |
http://mathhelpforum.com/calculus/108084-finding-normal-tangent-curve-print.html | # Finding normal and tangent of a curve
• October 14th 2009, 04:38 PM
Finding normal and tangent of a curve
Ok, i generally know how to find a tangent and it's normal by applying the f(a+h)+f(a)/h formula, but this equation apparently has tan(trig) and I have no idea how to deal with it:
y=2tan(pix/4) at x =1
• October 14th 2009, 04:50 PM
skeeter
Quote:
Ok, i generally know how to find a tangent and it's normal by applying the f(a+h)+f(a)/h formula, but this equation apparently has tan(trig) and I have no idea how to deal with it:
y=2tan(pix/4) at x =1
are you aware of the general formula for the derivative of the tangent function ?
$\frac{d}{dx} \tan{u} = \sec^2{u} \cdot \frac{du}{dx}$
finding the value of the derivative using the limit definition is going to be a bit long and overwhelming algebra-wise. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 1, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8005995154380798, "perplexity": 526.9834203390883}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398468233.50/warc/CC-MAIN-20151124205428-00047-ip-10-71-132-137.ec2.internal.warc.gz"} |
http://dml.cz/dmlcz/104159 | # Article
Full entry | PDF (0.5 MB)
Keywords:
system reliability; unit reliability; unit importance; essential unit
Summary:
The availability of a system with dependent units is obtained in the case where the system fails when one of the essential units fails. Markov model is assumed. The system considered consists of $n$ dependent units of which $r\leq n$ units are essential units. A unit is said to be essential if its failure causes the system to fail. The mean and variance of time to system failure are given. Unit reliability is also discussed.
References:
[1] John G. Kemeny J. Laurie Snell: Finite Markov Chain. D. Van Nostrand Company Inc., New York (1960). MR 0115196
Partner of | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9665179252624512, "perplexity": 2089.749902194131}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988719041.14/warc/CC-MAIN-20161020183839-00431-ip-10-171-6-4.ec2.internal.warc.gz"} |
https://hal-lara.archives-ouvertes.fr/hal-02102345 | # A Doubling dimension Threshold $\Theta(\log\log n)$ for augmented graph navigability
Abstract : In his seminal work, Kleinberg showed how to augment meshes using randomedges, so that they become navigable; that is, greedy routing computes pathsof polylogarithmic expected length between any pairs of nodes. This yields thecrucial question of determining wether such an augmentation is possible for allgraphs. In this paper, we answer negatively to this question by exhibiting athreshold on the doubling dimension, above which an infinite family of graphscannot be augmented to become navigable whatever the distribution of randomedges is. Precisely, it was known that graphs of doubling dimension at mostO(log log n) are navigable. We show that for doubling dimension >> log log n,an infinite family of graphs cannot be augmented to become navigable. Finally,we complete our result by studying square meshes, that we prove to always beaugmentable to become navigable.
Keywords :
Document type :
Reports
Domain :
Cited literature [24 references]
https://hal-lara.archives-ouvertes.fr/hal-02102345
Contributor : Colette Orange <>
Submitted on : Wednesday, April 17, 2019 - 11:23:29 AM
Last modification on : Thursday, November 21, 2019 - 2:38:40 AM
### File
RR2006-16.pdf
Files produced by the author(s)
### Identifiers
• HAL Id : hal-02102345, version 1
### Citation
Pierre Fraigniaud, Emmanuelle Lebhar, Zvi Lotker. A Doubling dimension Threshold $\Theta(\log\log n)$ for augmented graph navigability. [Research Report] LIP RR-2006-16, Laboratoire de l'informatique du parallélisme. 2006, 2+7p. ⟨hal-02102345⟩
Record views | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.23258663713932037, "perplexity": 7995.933445033661}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575540488870.33/warc/CC-MAIN-20191206145958-20191206173958-00275.warc.gz"} |
http://mathoverflow.net/questions/32752/the-comparison-between-the-square-of-the-functional-value-and-the-sum-of-squares/32811 | # The comparison between the square of the functional value and the sum of squares of the L^2 norms of function and its Laplacian
I was reading a paper where I came across the following argument :
For any x in M and for a geodesic ball B(x; epsilon) in a compact Riemannian manifold M with injectivity radius bigger than or equal to epsilon, and for any smooth eigenfunction f of Laplacian on M, we have :
the square of f(x) is <= C times ( the square of L^2 norm of f over B(x;epsilon) + square of L^2 norm of L(f) over B(x:epsilon)),
where L(f)= Laplacian of f, where C is independent of the Riemannian metric on M.
I was unable to see, with my limited Analysis knowledge, why this is true, but they mentioned that it follows from Sobolev's and Garding's inequality, for which they referred to S. Agmon's "Lectures on Elliptic boundary value problems"... still it is unclear to me.
N.B.: ihe injectivity radius of a manifold is the smallest of all numbers r such that I can have a geodesic ball of radius r around each point of M. e.g. injectivity radius of the sphere of radius 1 with standard metric is pi, injectivity radius of R^n is infinity etc.
Any help ? Thanks in adavance !
-
I would guess that the "eigenfunction" hypothesis is probably redundant,probably it should hold for any smooth function f on compact M, at least that is apparent from the way the steps are written in the paper. I cannot attach the paper here, because it is not available from mathscinet etc. – Analysis Now Jul 21 '10 at 6:45
You should probably make the title more descriptive if you want answers. – Harry Gindi Jul 21 '10 at 6:47
Just now I have done it, thanks ! – Analysis Now Jul 21 '10 at 6:55
The dimension of M is not larger than 3, is it? – Pietro Majer Jul 21 '10 at 7:12
Too add to Pietro's comment: roughly speaking Garding allows you to control the Sobolev norm $\|f\|_{H^2}$ by $\|f\|_{L^2} + \|\triangle_g f\|_{L^2}$. And in dimensions $\leq 3$ Sobolev controls $L^\infty$ by $H^2$. If there's any reason why they specify it only for eigenfucntions, it would most likely be for the fact that they want $C$ to be independent of the metric. – Willie Wong Jul 21 '10 at 10:07
You are working on a Riemann surface. That bit of information is rather important, as Sobolev inequalites depends rather much on the dimension of the space. The basic Sobolev inequality is $$\| f \|_{L^q(\Omega)} \leq C (\| \partial f \|_{L^p(\Omega)} + \| f\|_{L^p(\Omega)})$$ where the condition $\frac1p \geq\frac1q \geq \frac1p - \frac1n$ is satisfied (and $\Omega$ needs to be suitably regular). and $C$ depends on the set $\Omega$ and the coefficients $p,q$. If you want the sup norm on the left hand side, you can morally speaking replace $q$ by $\infty$ (so $1/q = 0$ and ask that the second inequality be strict).
In any case, in two dimensions by iterating the derivatives, you can actually show that for smooth $f$ $$|f| \leq C( \|f\|_{L^2} + \|\partial^2 f\|_{L^2})$$ using that $0 > 1/2 - 2/2$. (The 2 in the numerator is the number of derivatives. In the denominator in the first term is the Lebesgue exponent, and in the second term is the dimension.)
Now, a consequence of Garding's inequality states that for an uniformly elliptic differential operator $L$ of order $k$, one has that $$\| \partial^k f\|_{L^2} \leq C (\| Lf\|_{L^2} + \| f\|_{L^2})$$ so using that the Laplacian is uniformly elliptic of order 2, you can plug Garding's inequality into Sobolev inequality and square the whole expression to get what the authors claim.
As to the actual dependence of the constant $C$ on various parameters: off the top of my head I can't remember the details. So I suggest you look it up either in Agmon's book as the authors suggest, or in Gilbarg & Trudinger Elliptic Partial Differential Equations of Second Order or Adams Sobolev Spaces
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Oh, and by the way, the fact that $f$ is an eigenfunction is not used in this step. It is used in the next step where the Laplacian $\triangle_g f$ is replaced by $\lambda^2 f$, the eigenvalue. – Willie Wong Jul 21 '10 at 16:19
Thanks very much Mr. Willie Wong, I really appreciate your answer ! – Analysis Now Jul 21 '10 at 16:26
It seems to me that more needs to be said about the constant $C$. As far as I can tell, the constant $C$ depends on the metric $g$ and its Christoffel symbols with respect to local co-ordinates, and I don't think just knowing that the domain is within the injectivity radius is enough to get uniform ellipticity or uniform bounds on the Christoffel symbol. However, the paper in question appears to assume that the metric is hyperbolic (constant Gauss curvature equal to -1). That would be enough. – Deane Yang Jul 21 '10 at 16:49
Deane: is it not enough that $\epsilon$ is sufficiently small? Suppose we have a compact Riemann surface, the Gauss curvature is everywhere bounded, so on geodesic balls of size $\epsilon$ we can bound the Christoffel symbols (in geodesic normal coordinates, say) by something like $\epsilon R$, where $R$ is the upper bound of the Gauss curvature, and so the variations in the metric is bounded by roughly $\epsilon^2 R$ and so in the patch we have uniform ellipticity. I hope I am not missing something obvious. Of course, I agree with you that just "within injectivity radius" is not enough. – Willie Wong Jul 21 '10 at 17:12
Willie, your comment is essentially on the mark, but I didn't see any mention of curvature in either the question or your answer. If you have upper and lower bounds on the Gauss curvature, then you can definitely find co-ordinates in which you get full control over the constant $C$. Surprisingly, geodesic normal co-ordinates don't seem to work, but Jost and Karcher showed that "almost linear co-ordinates" do. But everything is a lot easier, if you just assume the metric is hyperbolic. – Deane Yang Jul 21 '10 at 18:14 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9718057513237, "perplexity": 217.7882270678841}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1413507443451.12/warc/CC-MAIN-20141017005723-00216-ip-10-16-133-185.ec2.internal.warc.gz"} |
http://tex.stackexchange.com/questions/110045/automatically-include-an-se-flair-in-output-document/110055 | # Automatically include an SE flair in output document [duplicate]
Under the assumption that my machine is connected to the Internet, how can I automatically include my TeX.SE flair in my output document at compile time?
My understanding is that an SE flair is just a .png generated server-side when queried; at least, that's what I gather from the HTML code on my flair page.
Note that I want the process to be automated; I do not want to "manually" download the flair and then "manually" include it with \includegraphics.
Therefore, the problem reduces to including an image from the Web, as in Can I use an image located on the web in a LaTeX document?.
However, I cannot get that solution to work for my flair. I use the following command (in TeXmaker 4.0.1, with TeXlive, on Mac OS 10.8.3):
"/usr/texbin/pdflatex" -synctex=1 --shell-escape -interaction=nonstopmode %.tex
Here is my code:
\documentclass{article}
\usepackage{graphicx}
\begin{document}
\write18{wget http://tex.stackexchange.com/users/flair/21891.png}
\includegraphics{21891.png}
\end{document}
and here is my output:
Subsidiary question: I haven't researched this very much, but is there an easy way to produce a pdf that will automatically query SE servers for an up-to-date flair? I'm guessing this would probably involve some Javascript (which the pdf reader should enable), as in How can I typeset the date/time at compile time?, but I'm not sure how to do it.
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## marked as duplicate by Jubobs, Werner, doncherry, clemens, GuidoApr 22 '13 at 20:30
Everything works fine here. I'm using Lubuntu 11.10 with TeX live 2011. – Sigur Apr 22 '13 at 13:44
@Jubobs: take a look at tex.stackexchange.com/questions/88430/… – Papiro Apr 22 '13 at 14:22
When I try it it works the second time (making wgert fetch it again to a renamed _ version. I assume there is a timing issue that the file is not available for reading quick enough due to the buffering somewhere. Simpler just to run wget before pdflatex:-) – David Carlisle Apr 22 '13 at 14:48
may be @Papiro should make an answer to gain weight if he is interested – texenthusiast Apr 22 '13 at 14:48
@Papiro As texenthusiast wrote, feel free to post your own answer, and I'll delete mine. – Jubobs Apr 22 '13 at 15:01
This solution worked for me (with -shell-escape enabled).
Thanks to @Papiro for his link!
Of course, you'll have to substitute your user number for mine, if you want to include your own flair :)
\documentclass{article}
\usepackage{graphicx}
\newcommand*{\grabto}[1]{%
\IfFileExists{#1.png}{}{%
\immediate\write18{%
curl \detokenize{http://tex.stackexchange.com/users/flair/}#1.png -o #1.png%
}%
}%
}
\grabto{21891}
\begin{document}
\includegraphics{21891.png}
\end{document}
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Does that make this question a duplicate? – doncherry Apr 22 '13 at 18:58
Yes, I suppose, although my subsidiary question remains open. – Jubobs Apr 22 '13 at 19:28
@Jubos Your subsidiary question is about a pdf with an image that updates after compiling, if I understand correctly? I guess the cleanest way of handling this we close this question as a duplicate and you ask the subsidiary question as a follow-up question. – doncherry Apr 22 '13 at 20:15 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6805369257926941, "perplexity": 1865.3574206205278}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-30/segments/1469257824204.27/warc/CC-MAIN-20160723071024-00095-ip-10-185-27-174.ec2.internal.warc.gz"} |
http://adamdennett.co.uk/category/uncategorized/ | London’s Real Centre Point
So yesterday afternoon, just before I was about to go out to a meeting and then home, London Live contacted the CASA offices to see if someone was available to talk about a story appearing in Today’s Evening Standard about someone from an Estate Agents deciding that London had a new centre point!! Oh, and it was some bench on Victoria Embankment.
They wanted someone with a bit of spatial nous to come and talk at some ungodly hour this morning, about whether or not this really was the new centre of London. Sadly they contacted us too late in the day (plea to media people – 3.30 in the afternoon for something the morning after is not enough time given meetings and general living of life!) for anyone to appear, but had they have gotten to us a bit earlier in the day, this is what they would have got from me!
Short answer – NO IT`S BLOODY WELL NOT THE NEW CENTRE OF LONDON!!!
Let me explain…
So in the article, apparently Knight Frank “using techniques developed by Army cartographers” (no less!!) have decided that the centre of London is at 51°30’37.6”N 0°06’56.3”W, and this, indeed, is on the Embankment just behind Somerset House, probably near the bench in question.
“But how the hell did these advanced Army techniques arrive at this location?” I hear you ask. Well, London Live sent us through the original press release from Knight Frank, which reveals their methodology. In their release is this picture:
And next to the picture they explain that their calculation is in fact based upon ‘central London’s inner ring road’ (highlighted in red here). So in fact what Knight Frank have done is create a polygon from the central ring road, take the geometric centroid of that polygon and then decide that this is the new centre of London!
Excuse me while I let out a little WTF?!
OK, so the new centre of London is now based on one tiny bit of the central London road network, not the rest of the road network, or the M25 or on any of the other features of the city such as its population or its built up area, or the boundaries of its boroughs or anything like that, just one little section of road? Yes.
I can be sure this is what they’ve done because I have been able to use the same advanced Army mapping techniques (which are remarkably similar to the basic undergraduate GIS techniques I am also familiar with) to reproduce their work:
Here I took some data from Open Street Map on the central London road network, filtered by ‘Trunk Roads’ and selected the central ring road bit I was interested in. Converting this road segment into a polygon (quite easy using the ‘dissolve’ feature in ArcGIS) I could then calculate the geometric centroid of the shape – hey presto the new centre of London!!
Or not. Now I don’t know about you, but I’m not too happy with defining the centre of a massive city like London just by some arbitrarily chosen section of road, that just happens to be sort of circular and sort of in the middle. I think we can be a little more sophisticated with our advanced army techniques!!
What about if we argue that the extent of London is actually all of the Boroughs (and the City of London) that make up the Greater London area? What if we use our army calculation machine (otherwise known as basic maths – seriously, try it here with a triangle) to work out the geometric centroid of the London Boroughs? Surely this would be better?
Ooh look, the centre of London has changed! It’s now on Waterloo road just South East of Waterloo station!
But what if geometric centroids aren’t the best way of measuring the centre of gravity of a place. I mean, sure, they are great for shapes, but London is a bit more than a shape. It’s a city full of people. Are London’s people not important in all of this? Fortunately there are things we can do to take account of London’s people when trying to define a true centre – something that our army friends in all their wisdom failed to explain to Knight Frank!
Us geographers quite often use things call ‘Population Weighted Centroids’ – these take account of where people actually live in an area, and shift the geometric centroid accordingly.
Results from the 2011 Census (probably best estimate of London’s population distribute we have) are released for zones of around 300 people called Output Areas. The Office for National Statistics has very kindly calculated a whole set of population weighted centroids for these areas across England and Wales. What I have done here then, is calculate the mean centre of all of the population weighted centroids for all of the output areas in all of the London Boroughs. Do we get a different centre of London? You bet!!
So as you can see, if we take population into account the centre of London moves yet again and can this time be found somewhere in the Shell Centre just off the entrance ramp to Waterloo Bridge.
Now I could go on – essentially there are any number of ways that we can calculate the centre of London (I could go into the London Travel to Work area, the extent of the Oyster Card zone, the postcodes we use in London, the built up area, but I won’t – for every definition of London Ollie O’Brien talks about in his discussion of ‘Where is London?’, we could define a new centre quite easily), but I would argue that the Knight Frank Centre, being as it is just based upon the geometric centroid of some arbitrary bit of circular road, is certainly NOT the centre of London.
It’s also worth noting that, in case you’d not guessed from my tone, these are not techniques developed by army cartographers, these are basic techniques that anyone who studies an undergraduate geography degree in the UK will learn. And as an undergraduate geography student will be able to tell you, drawing a map or creating a centroid from a polygon is easy once you’ve been shown how – thinking about what you are showing and justifying the decisions you make is the hard bit!
———————————————————————————————-
A post-script
Since I originally wrote the little rant above, I’ve been in contact with Ian McGuinness at Knight Frank who did the original analysis (pre the Chinese-Whisper-Mill that can be the press office, the journalist, the editor, the TV report off the back of the story) – he was understandably a little put out by the tone of the piece above, and this made me realise that perhaps the direction of my ire was not as clear as I though as I thought when writing the blog.
Just to be clear, my beef is with the press hanging on the ‘army techniques’ thing and using this as a lever in the old argument from authority ploy to assert that this is categorically the new centre of London. No Evening Standard and London Live, this is not the new centre of London, this is just one of a number of possible centres of the city which could be defined in a whole range of different ways, depending on what you think is the most important feature of the city. Implying that ‘this is’ rather than ‘this could be’ the new centre by invoking the technical prowess and accuracy of the army is bad form and something that will rattle the cages of academics all day long!
The techniques are standard, the results are subjective, but of course this doesn’t make for a good news story! I know that the headline – “One of many new alternative centres to London proposed” is not as catchy as “London’s real centre point is next to bench on the Victoria Embankment by the Thames” but if you had maybe waited a day before running with the story, I would have been available then to explain this on your TV show!
Cartograms!!
About 6 months ago I did a bit of work for the conference which became colloquially known as the ‘Two Tonys’ conference – it was a bit of a jamboree held at the Royal Geographical Society to celebrate the long and illustrious careers of Tony Champion and Tony Fielding – if you’re interested the conference website is here. If you’re totally mental, then you can actually listen to my whole presentation on that site, although I really wouldn’t recommend it!
Anyway, for some reason I totally forgot to post the pretty little maps I produced for my presentation, so here they are now…
For those of you who are not down with some of the trickery us geographers get up to when amusing ourselves on dark, lonely, winters evenings, these little blighters are called CARTOGRAMS. Yes, that’s CART-O-GRAM-Z. They’re made by force-feeding digital boundaries, foie-gras style, until those that have been really bad are totally bloated and ready to burst, and those that have been even more bad are neglected and become shrivelled shadows of their former selves (good boundaries are left relatively physically unscathed by this process, but are often mentally anguished at the treatment of their peers).
But why do us sadistic geographers from time-to-time subject these poor boundaries to such inhumane treatment? No, we’re not all closet feeders – it’s actually a pretty nice way to deal with the distorting effects of area size when presenting data for discrete geographical zones. Very often the interesting stuff happening in London, for example, gets lost as London Boroughs are very much smaller than other local authorities in the UK – cartograms help counteract this visual trickery a little bit.
So, after skillfully dodging boundary-rights activists (yes, an occupational hazard for us geographers) and subjecting a selection of local authority areas to some inhumane treatment, here are the results:
Firstly, those who have a holiday home second address are disproportionately located in rich London boroughs (City of London, Kensington and Chelsea)
And where do the stinking rich go on holiday…? Here:
Yes, they all go swanning off to the coast – very nice I’m sure! Well, that is apart from those who go on holiday in the City of London. Yes, I’ve heard it’s really nice there and nothing at all to do with council tax dodging or anything like that.
What? You mean to say that there might be people in England and Wales who take advantage of the generous 50% discount given on second homes by some local authorities who might not be telling the whole truth about what constitutes their second home? That, for example, someone living in a small pied-à-terre in the City of London a couple of days a week (with low council tax) might be trying to fob off their massive country pad (with high council tax) as their second home? Surely no upstanding City employee would be so deceitful? Well, the data might suggest otherwise!
Some of this ‘creative’ home ownership may also be evident in the location of second homes for work:
Well all of this England and Wales holiday home talk is very nice, but what about the serious loads-a-money’s who don’t want to take a chance with the dodgy British weather – where do they all live?
Oh yeah, of course, they all live in London – duh!
So what can we conclude from all of these lovely maps? Well,
• London is the driver of second address activity in England and Wales
• Richest boroughs (City, Kens/Chelsea, Westm, Ham/Ful) are both:
–main address for people with holiday home second addresses elsewhere
–and second address work locations for people with a main address elsewhere in the country
• Home counties dwellers very unlikely to have second home work address elsewhere
• South-West and Wales most popular locations for holiday homes and main home owners with second address elsewhere
• The system appears to be driven by those living (either mainly or partially) in wealthy central London boroughs
• The release of interaction data (Q3 2013?) and small area statistics (Q1-3 2013?) will allow for more detailed analysis:
–Which small areas experience highest rates of multiple address dwelling and what are the socio-economic impacts?
–What are the socio-economic characteristics of those who own holiday homes / second work addresses?
–What are the flow patterns associated with second addresses? Not just second home owners, but split family relations and detailed student mobility patterns
** No area boundaries were harmed in the making of this blog post **
London’s Changing Population
A few weeks ago I was approached by BBC London to carry out a bit of analysis in relation to London’s ever-changing and growing immigrant population. Obviously something more interesting came along in the world of London-based topical news, as the stuff I did never made it to air (or at least, even if it did, they didn’t tell me about it)!
Well, the BBC’s loss is the blogosphere’s gain as you lucky people can now get the full, unabridged juicy findings – I hope you enjoy (most of the maps come at the bottom map fans)!
I should probably point out that given the limitations of the data released so far from the 2011 Census (univariate tables in the main), this is pretty light on analysis, heavy on presentation of data. That said, the facts on their own are pretty interesting.
——————————————————————————————————————
All of the observations below have been made using data from the 2011 and 2001 Censuses, administered (in England and Wales) by the Office for National Statistics (ONS). These data are available under the Open Government Licence – http://www.nationalarchives.gov.uk/doc/open-government-licence/open-government-licence.htm
Summary
London is a growing city with over 1 million more inhabitants than there were 10 years ago. A significant amount of this growth has been fuelled by international migration (although even more people arrive each year from other parts of the UK). Consequently, our Capital is now an even more international city than it was ten years ago with 37% of its population not born in the UK (compared to 27% then). Most of the foreign born living in London are from the rest of Europe, but there are significant populations from all parts of the globe.
Examining changes in London’s foreign born population from 2001, people born in Poland show the largest gross increase in numbers, up 136,076 (900%) to 158,300 people. Changes in the numbers of foreign born have also altered the structure of the city’s population, with areas across the city becoming slightly more polarised – foreign born now more likely to located in areas with other foreign born and UK born more likely to be located in areas with other UK born than they were in 2001.
While London can be described as a young immigrant city with almost 20% of the population arriving from overseas in the last 10 years and most of these in their 20s; it can also be described as a city of assimilation – people living in London are only slightly less likely than those in the rest of England and Wales to have a UK passport.
London is a multilingual city with English the main language of only 78% of Londoners (compared to 92% of the rest of England and Wales). After English, South Asian languages are spoken most widely (some 6.5 of the population) with Polish the main language of almost 2% of the population. Of the 22% of Londoners who don’t speak English as their main language, 18% can speak English well or very well. Only 4% have poor English skills, although these people are not spread evenly across the city – in Newham, Tower Hamlets and Brent around 8% of the population have poor English language skills.
Analysis
Country of Birth
London’s Population Composition by Region of Birth
• London’s population has increased by 14% (1,001,850 people) between 2001 and 2011
• While most of London’s population have been born in Europe (76% – which includes those born in the UK) and there has been an 8% increase in the total number of Europeans, the proportion of Londoners born in Europe has declined from 80% to 76%, driven mainly by a reduction in UK born.
• Almost 1 million Londoners were born in Asia in 2011, up 52% from 2001
• UK born (not shown in table) are now 63% of the London population, compared to 73% in 2001.
Top Ten % Increases in Population by Country of Birth
• In terms of the % increase in population (i.e. the number of people in 2011 compared to the number of people in 2001), those born in Romania have the largest increase, followed closely by those born in Poland, those born in China and those born in Scotland.
• The number of people born in Romania in the Capital is not very large at only 44,848 (0.6% of the population). The % increase is large as in 2001 there were only 3,049.
• The largest increase in those born abroad has been those born in Poland – an additional 136,076 are now living in the Capital. A rise since 2001 from 0.3% of the population to almost 2%
• The numbers of foreign born people have risen across England and Wales since 2001, but compared to the rest of England and Wales, the proportions of foreign born in London have increased by more.
• There are fewer UK born people living in London now (5,175,677) than there were in 2001 (5,231,701). The largest decrease has been those born in Northern Ireland (75,908 fewer).
The maps below show the location quotients of the UK born population within London – these show population concentrations with areas >1 above the average for the city and <1 below average.
UK born population are more heavily concentrated in the outer boroughs, with a below average presence in the ‘Inner London’ boroughs.
• Between 2001 and 2011, these spatial concentrations have become more polarised, with concentrations becoming even heavier in the outer boroughs and even less heavy in the inner boroughs (see the animation .wmv file below for animated transition). This is partially a consequence of the far lower proportion of UK born in the city acting to intensify concentrations, although even when accounting for this, the gap between lowest and highest concentrations is increasing slightly.
LQTransition
• The change map above shows how and where the concentrations of UK born population are evolving in London. ‘Strong’ shows where above average concentrations of UK born were in 2001; weak, where concentrations were below average.
Passports Held
• London’s proportion of people with UK passports (71.2%) is not dissimilar to that of the rest of England and Wales (75.7%), despite a larger % of people being born abroad. This suggests that whilst London is a city of immigrants, it is also a city of assimilation.
• Less than half of the people in London compared to the rest of England and Wales (7.8 vs. 16.9) have no passport – indicative of the volume of internationally mobile people within the city.
Length of Residence in the UK
• 63% of London’s population were born in the UK (compared to 87% in the whole of England and Wales)
• London is home to 40% of the people living in England and Wales who were not born in the UK
• 4.5% of people living in London arrived in the last 2 years, 10% in the last 5 years
Year of Arrival
• Year of arrival data confirms London’s status as a city of new arrivals – almost 20% of the population of the City arrived here in the last 10 years and almost 3 times that of the rest of England and Wales.
Main Language Spoken
• English (or Welsh) is the main language spoken by 78% of Londoners (compared to 92% in the rest of England and Wales).
• South Asian languages are, after English, the most frequently spoken with ½ a million Londoners (6.5%) defining it as their main language.
• Polish is the third most popular main language spoken with almost 2% of Londoners speaking as their main language.
**See the maps at the bottom of this post for the spatial concentrations of these languages in London**
Proficiency in English
• A higher proportion of people living in London cannot speak English well or at all, than in the rest of England and Wales (4% vs. 1.6%)
• There is a distinct geography to poor English language skills in the Capital…
• Three boroughs (Newham, Tower Hamlets and Brent) have over double the average rate of those who state in the Census that they cannot speak English well or at all – up to 8.2% of the population in these areas.
• Location Quotients compare distributions of a particular variable with the national average. A score greater than 1 indicates that the area has a greater share of that variable compared to average. The map below highlights areas of London where people with bad or no English language skills are concentrated:
• Poor English skills are particularly prevalent in Newham, East Haringey, South Waltham Forest, Tower Hamlets, South-East Enfield, Brent, Ealing, South Hillingdon and North-West Hounslow. Poor English skills are less prevalent in South London.
Age of arrival into the UK
• For those not born in the UK, the most common age group of arrival is the 20-24 age group (in line with the age of peak migration across the world). People in this age group comprise around 22% of all migrants arriving in the capital
• 41% of all migrants arriving in the capital are in their 20s – although this is not much higher than the 38% of migrants in the rest of England and Wales.
London’s Religious Concentrations – Part III
OK, I wasn’t going to spend any more time on this, but as always once you get started with something like this, it’s hard to put it down!
This post has been inspired by very similar questions posed by Nicola Shelton and Colin MacInnes on my Facebook wall – the gist was “this is all very nice, but have you thought about religious diversity?” i.e. where are the places with the most different religions and where are the places where it’s all pretty homogeneous?
After a bit of thinking out loud on my facebook wall about how to calculate such an index, I ended up doing what most sensible people do these days – I had a bit of a Google around! Several years in academia have taught me that if you have a bit of a conundrum, chances are, most of the time, someone else will have had a very similar problem and posted an answer on the web!
So it turns out, diversity is something ecologists are pretty into – they bloody love looking at whether or not areas contain a diversity of species and have developed/plundered from other disciplines (like us geographers love to do) a plethora of indices to quantify the diversity phenomenon. One of these is the Gini-Simpson index (sometimes described as just “the Simpson Diversity index” or similar – see this Wikipedia page for a description of the difference). I could’ve also used Shannon Entropy as a measure, but much of my life for the last 2 years has been to do with Entropy maximising, so I thought I’d leave it in the bag this time!
The Gini-Simpson index is a measure of the diversity of an area. It takes into account the number of different groups in the area as well as the relative abundance of those groups. The index can be calculated using the following formula:
$D_{i}=1-\left(\frac{{\displaystyle \sum_{j}}\left(n_{ij}\left(n_{ij}-1\right)\right)}{N_{i}\left(N_{i}-1\right)}\right)$
where $D_{i}$ is the Gini-Simpson diversity for area $i$
$n_{ij}$ is the total number of people in area $i$ who are classified in religion $j$
and where $N_{i}$ is the total number of people across all religions $j$ in area $i$, or:
$N_{i}={\displaystyle \sum_{j}\left(n_{ij}\right)}$
The index ranges between 0 and 1. 1 represents an infinite diversity, 0 represents no diversity (or complete homogeneity, if you’d rather).
I calculated this index for each output area in London, and it produces some rather pretty maps. In addition, I also calculated a standardised ratio which enables you to look at the religious diversity of an output area, compared to the average diversity for the whole City. Of course, the denominator need not be London, but could easily be England and Wales, or the whole UK.
I’ve not seen anyone talk about using a standardised ratio anywhere, so in honour of Colin sparking my interest, I shall dub it the ‘Colin-Gini-Simpson or Colin-Diversity Ratio’. If you like algebra, the equation for calculating the Colin-Diversity ($CD$) Ratio for area $i$ is:
$CD_{i}=\frac{D_{i}}{D}$
where
$D={\displaystyle \frac{\sum_{j}\left(N_{j}\left(N_{j}-1\right)\right)}{T\left(T-1\right)}}$
where
$N_{j}={\displaystyle \sum_{i}n_{ij}}$
or the total number of people in each religious group across the whole city.
And
$T={\displaystyle \sum_{i}\sum_{j}n_{ij}}$
or the total number of people in the city.
Yes, yes, I know, that’s enough tedious algebra – WHAT ABOUT THE MAPS?!?!?! OK, so here we are. First up is the standard Gini-Simpson map of religious diversity. Should probably note that the reference index for the whole of London is 0.699 (remember, 1 being infinitely diverse, 0 being completely homogeneous) – so pretty diverse, as we might expect. The range of values is quite large as well, with the least diverse output area (0.19) E00004097 – which is in Bromley in South London. The most religiously diverse OA is E00010619, which is the area to the South of Canons Park in Harrow, north London.
As might be expected, with the higher LQs for most religious groups in North London, the most religiously diverse areas are in this half of the city, with much less religious diversity in the South.
The next map is the Colin index, which shows quite neatly areas which are above or below the average diversity for London:
There’s a bit of negative skew in the data, with more OAs being less religiously diverse than the Gini-Simpson score for the whole city.
And one final map, just to finish this whole thing off – this map shows the most popular religion by OA, i.e. were you in that output area, this is the religion that most people you come across will be – enjoy!
***Oops, just spotted an error (mine!) Where it says Buddhist, is should really be Hindu – will fix the map on Monday, but the pub beckons now!!!)***
London’s Religious Concentrations – Part II
OK, as I still had ArcGIS cranked up on my machine and this appears to have been a popular blog topic, here are a few extra maps to finish off the London’s religions post.
So, in order of whether or not adherents are likely to enjoy all traditional flavours of monster munch, I shall proceed…
Jedi
Interesting patterns of concentration for the Jedi here – essentially they are not very concentrated at all. Not suffering from the internal dogma or external persecution which has led to the clustering of a number of other religious groups in the capital (plus their ability to employ rather useful ‘mind tricks’ on property gate-keepers who would have otherwise encouraged them to rent property in areas where ‘their lot’ were already starting to cluster) the Jedi are perhaps the least spatially concentrated religious group in the capital. A case study in diversity and multicultural integration if ever I have seen one!
Religion not stated
“Yeah, screw you Nanny State – I ain’t gonna give you my deets! You ain’t gonna know my shizzle!” Or something like that. Yes, some people would rather not say if they believe in any hocus pocus or not. How knows why this is? Maybe disdain for the government and its Census form. Maybe they are secretly embarrassed about believing that the words of 20th Century science fiction writer are anything other than a total load of rubbish. Either way WE STILL KNOW WHERE YOU LIVE! In Camden, Islington and Tower Hamlets, by all accounts… Yes, the ‘rather not say if you don’t mind’ brigade are real central London dwellers. I would suspect that those in Tower Hamlets may have different motivations for not saying than those in the leafier north London suburbs, but the patterns probably warrant some further investigation at some point.
Buddhists
Buddhists are a bit like the Jedis – all over the place! Lets just hope the Jedi don’t start training the buddhists (they’re both a bit Zen, so probably would find some common ground) or the number of light-sabre related admissions in London A&E departments may rise quite rapidly…
Sikhs
Still some pretty high concentrations in West London (Hounslow, Ealing) and in the Redbridge – areas with traditionally high concentrations of this group…
Hindus
Similar concentrations to Sikhs in Redbridge, but also high concentrations in Brent and Harrow.
Jews
Jewish population in London are still heavily concentrated in the Northern-most boroughs. Location quotients are particularly high at their highest (well over 20 and up to 60, compared to only about 7 at the maximum for the Muslim population in London)
So that’s it folks – hope you’ve enjoyed the maps! Until my next period of procrastination…
New Census data – London’s religious concentrations
So, today the ONS treated us with some brand spanking new Census data, all the way down to Output Area level (zones of about 150 to 500 people).
The data contains some interesting headline facts and some fascinating spatial patterns…
For example, fact fans, in London there are 173 people for whom ‘Heavy Metal’ is their religion. There are 85 Druids. Only 64 Scientologists (which is surprising considering how often they bug me as I walk down Tottenham Court Road!). 5,637 Jedi Knights (although no Sith). 27 total nut-jobs who are into Witchcraft – exactly half the number who are Satanists.
As always, it’s a bit of a race for the geography geeks to get their maps out first – I’m sure James Cheshire has probably already beaten me to this and got his map in the Evening Standard already, but here are some of my first rough and ready efforts…
What have I chosen to map? Religion of course (what else?!)! It’s always quite an interesting thing to look at, especially in London and especially since the enlightened now count for a much larger percentage of the population than ever before!
I’ve decided to use Location Quotients – First introduced to me quite a few years ago now by the legendary Phil Rees (the actual material he used can still be found online here if you’re interested) – as they are quite a nice way of getting to grips with the relative concentrations of different groups across an area.
The LQs I’ve calculated here use the whole of London as a base, with values <1 (grey) indicating a lower concentration in that particular OA for the variable in question, and values >1 indicating a higher concentration.
So what have we got? Well, as a card-carrying atheist of course I’m going to be interested in where the godless are concentrated:
Far more godless in South London by the looks of things…
And Christians?
Not very many in Islington and Camden – not sure how this compares with the concentrations of Satanists and Heavy Metallers (and I doubt a causal link!)
And the last one for now – Muslims…
Apologies for no real analysis as such, but I’m sure we’ll see plenty emerge as more people get their mitts on the data… I may also post a few more tomorrow if I have time!
Working paper fun
Just to prove that I’ve not been twiddling my thumbs for the last 12 months, here’s the first (of hopefully many) working papers to come out of the ENFOLDing Migration stable…
Alan Wilson and I have been working on a new family of Spatial Interaction Models for estimating inter-regional migration flows in Europe. We’ve developed a new multi-level model which uses internal migration data at the regional level and international migration data at the country level to model international regional level flows.
Once I’ve finished tidying up the code, I’ll post the full model here too for people to play with – at the moment though, you’ll just have to make do with the paper, which can be found here:
http://www.bartlett.ucl.ac.uk/casa/pdf/paper175.pdf
And here’s a pretty picture from it!
New paper from me and the sad end of an era…
Yes, British migration classification fans, it’s the moment you’ve all been waiting for – publication of the CIDER Migration Classification paper! *Cue delirious cheering, whooping, hollering and cries of ‘get in the hole!!’*
This most recent product of my blood, sweat and tears – co-authored by John Stillwell – can be found in the latest edition of Population Trends. I say latest, but I should also say final, as sadly after 36 years of publication Population Trends is from today, no more. In 2010 the Office for National Statistics took the decision to cease regular publication of all of its journal titles – I can only speculate the victim of the severe cuts being enforced across the public sector currently.
The Autumn 2011 issue really does mark the end of an era and I will be sad to see it go, especially as I think I can safely say that it is the journal, above all others, that has been the source of useful and practical research during my academic career.
Iterative Proportional Nitwit
Iterative Proportional Fitting? That old chestnut? Haven’t people been banging on about that for hundreds of years?! Well, about 70, but I guess some of the old ones are the best ones… (Deming and Stephan for all those pub quiz fans out there!)
Anyway, I recently stumbled across IPF again in the way that people who work with data matrices do from time to time. I also realised that there’s not a whole lot of useful generic programmes out there for you to carry out this pretty useful procedure, and like a total nit, I’ve been doing it the hard way for a long time. Therefore I have spent the last day or so writing a nice little bit of VBA (arrghh, not Microsoft?! Yes! And it even runs in the much maligned but fantastic Excel). The program will take in data in either matrix or paired list format and will run IPF to update the interior cell values to a new set of column and row margins whilst maintaining the original ratio structure of the table.
I think Paul Norman produced a similar program in Excel a few years ago, but if you can find it anywhere on the web you’re a better Googler than me! Hopefully this programme improves Paul’s a little with the flexibility for matrices and paired lists and with it taking advantage of the increased number of columns available in the latest versions of Excel. Also, this will be freely available to download from here from now on. If you’d like to use the program, it can be downloaded from the link below:
http://dl.dropbox.com/u/8649795/DESKTOP_IPF.xlsm
Enjoy!
Oh and here’s a nice picture that my ENFOLD-ing colleagues will enjoy! | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 16, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.203545942902565, "perplexity": 1596.735435185987}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-35/segments/1440644060173.6/warc/CC-MAIN-20150827025420-00235-ip-10-171-96-226.ec2.internal.warc.gz"} |
http://mathhelpforum.com/differential-geometry/82731-homeomorphism-metrizability.html | # Math Help - Homeomorphism and metrizability
1. ## Homeomorphism and metrizability
Prove that if X is a metrizable topological space and Y is homeomorphic to X, then Y is metrizable
2. Originally Posted by Andreamet
Prove that if X is a metrizable topological space and Y is homeomorphic to X, then Y is metrizable
Since X is a metrizable topological space, we have a metric space (X, d).
Let Y be a topological space homeomorphic to X and $f:X \rightarrow Y$ be a homeomorphism.
Define d' on $Y \times Y$ such that
$d'(y_1, y_2) = d( f^{-1}(y_1), f^{-1}(y_2)), y_1, y_2 \in Y$.
I'll leave it to check d' is indeed a metric.
Since both $f$ and $f^{-1}$ are continuous bijection, we see that $f$ and $f^{-1}$ are isometries, which implies that an open ball of radius r >0 with respect to a metric d on space X corresponds to an open ball of radius r with respect to a metric d' on space Y, and vice versa. Now, the open balls in Y defined by d' can be given as a basis for a topological space Y. Thus, Y is metrizable. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 7, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9234822988510132, "perplexity": 260.2817610138693}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1405997901076.42/warc/CC-MAIN-20140722025821-00158-ip-10-33-131-23.ec2.internal.warc.gz"} |
http://math.stackexchange.com/questions/183601/on-the-definition-of-the-hausdorff-distance | # On the definition of the Hausdorff distance
$\newcommand{\dist}{\mathrm{dist}\,}$ Let $M$ be a metric space and $\emptyset\neq A,B\subset M$ bounded closed subsets. The Hausdorff distance is defined as $$h(A,B)=\max\{\dist(A,B),\dist(B,A)\},$$ where $$\dist(A,B)=\sup_{x\in A}\inf_{y\in B}d(x,y).$$
Why do we define $\dist(A,B)$ in this way? Is't it possible to replace the supremum by the infimum in the definition of $\dist\!$, that is, define $$\dist_{\mathrm{new}}(A,B)=\inf_{x\in A}\inf_{y\in B}d(x,y).$$
What is the impact of this 'new' definition on the 'Hausdorff distance' given by $$h_{\mathrm{new}}(A,B)=\max\{\dist_{\mathrm{new}}(A,B),\dist_{\mathrm{new}}(B,A)\}?$$
-
One problem that arises if you replace the sup by an inf is that the resulting distance function fails to be a pseudometric, as the triangle property fails to hold. For example, consider the sets $A=\{1\}$, $C = \{-1\}$ and $B=\{z\in\mathbb{C} | |z|=1 \}$ in $\mathbb{C}$ with the usual topology. We then have $d(A,B)=d(B,C)=0$, but $d(A,C)=2$. – Old John Aug 17 '12 at 12:16
Another problem (related to @Old John's observation) is that your suggested distance is zero already if $A$ and $B$ share a point while the Hausdorff distance is a genuine distance function. – t.b. Aug 17 '12 at 12:18
The intuition behind Hausdorff distance is to measure “how similar” two sets are in the metric sense. If two sets are in small Hausdorff distance, they are supposed to “look” almost the same.
For example, if $A$ was some arbitrary compact set on the plane and $B$ was its countable dense subset, then the Hausdorff distance between them would be zero, which is to be expected, since they “look” pretty much the same, if you don't look too close. You might want to take a look at the picture in the Wikipedia article, I found that it is quite helpful to intuitively see how the distance works.
Furthermore, if we take a locally compact metric space $X$, Hausdorff distance turns the set $\mathcal K(X)$ of non-empty compact subsets of $X$ into a well-behaved metric space (into which $X$ naturally isometrically embeds). Your definition could not do such a thing, because it would fail pretty much all axioms of metric except nonnegativity and symmetry.
That's not to say that what you defined does not make sense (though, as suggested by t.b., the symmetrisation is unnecessary, because $\inf_{x\in A}\inf_{y\in B}d(x,y)=\inf_{(x,y)\in A\times B} d(x,y)=\inf_{y\in B}\inf_{x\in A}d(x,y)$). It does measure how “close” sets are to one another. It's just that it's not what Hausdorff distance is about.
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More specifically, the suggested distance measures the minimal distance of points $(a,b)$ with $a \in A$ and $b \in B$. The symmetrization is unnecessary, since the suggested "distance" simply is $\operatorname{dist}_{\rm new}(A,B) = \inf_{a \in A, b \in B} d(a,b)$ which is already symmetric in $A$ and $B$. – t.b. Aug 17 '12 at 12:40
@t.b.: good point, I incorporated that comment into the answer. – tomasz Aug 17 '12 at 12:47
Here's my intuition on how you could have invented the Hausdorff distance. Hopefully it helps.
You want a metric that tells you how far two compact sets are from being the same. And since these sets happen to be subsets of a metric space, you ought to define your metric in terms of the distances between the points of $A$ and $B$.
Suppose $A\ne B$. Then either there is a point in $A$ that is not in $B$, or there is a point in $B$ that is not in $A$ (or both).
Let's say there is an $a\in A$ with $a\not\in B$. How far is $a$ from being in $B$? Well, the least you have to move $a$ to get it into $B$ is the distance to the closest point in $B$, which is $\inf_{b\in B} d(a,b)$. So that's the distance from $a$ to $B$, which we might as well call $d(a,B)$. Observe that if $a\in B$ then $d(a,B)=0$, and because $B$ is compact, if $a\not\in B$ then $d(a,B)>0$.
Now there are lots of points $a\in A$, some of which may be in $B$, and some may not. As long as there exists any $a\not\in B$, that is, any $a$ such that $d(a,B)>0$, we want to know about it. So we ought to take the supremum: $d_1(A,B)=\sup_{a\in A}d(a,B)$. This also means that every point in $A$ is at most $d_1(A,B)$ away from $B$.
Finally, $d_1(A,B)$ only tells us if there is a point in $A$ that is far from $B$. We want the Hausdorff distance $d_H(A,B)$ to be large if either there is a point in $A$ far from $B$, or there is a point in $B$ far from $A$. So we define it to be the maximum of both $d_1(A,B)$ and $d_1(B,A)$. And we're done.
- | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9851895570755005, "perplexity": 139.46232249754465}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-18/segments/1429246662032.70/warc/CC-MAIN-20150417045742-00186-ip-10-235-10-82.ec2.internal.warc.gz"} |
https://math.stackexchange.com/questions/1841645/smooth-structure-in-reconstruction-theorem | # Smooth structure in reconstruction theorem
Let $M,F$ be smooth manifolds, $\{U_i:i\in I\}$ an open cover of $M$ and a cocycle $\{t_{ij}:U_i\cap U_j\to\mathrm{Diff}(F)\}$. In almost any book which discusses fibre bundles, one can find the theorem that says that you can construct a smooth fibre bundle with fibre $F$ from these data, but no one proves it explicitly. So I thought, let's prove it.
We take the disjoint union $\coprod_{i\in I}U_i\times F$ and the equivalence relation which relates $(p,f)\in U_i\times F$ and $(q,g)\in U_j\times F$ iff $p=q$ and $f=t_{ij}(p)g$. Then $E$ is the quotient space equipped with the quotient topology, and the map $\pi:E\to M$ sending $\overline{(p,f)}$ to $p$ is continuous. The restrictions $q|_{U_i\times F}:U_i\times F\to q(U_i\times F)=\pi^{-1}(U_i)$ are homeomorphisms, and should become the local trivialisations. It remains to show that $E$ is a smooth manifold, that $\pi$ is smooth and that these local trivialisations are smooth (and that the topology on $E$ is Hausdorff/second countable), and this is where I got stuck. Does anyone have any idea how the smooth structure on $E$ is defined? It should be defined by the smooth structure on $M$ and $F$, but I don't see how.
Edit: obviously $E$ is Hausdorff and second countable because $M$ is and $\pi$ is continuous.
Edit 2: a smooth athlas for each $U_i\times F$ is given by $\mathcal{A}_i\{((U\cap U_i)\times V,\phi|_{U\cap U_i}\times\psi)\,|\,(U,\phi)\in\mathcal{A}_M,(V,\psi)\in\mathcal{A}_F\}$, clearly. How is then the atlas for the infinite coproduct defined? Is it just $\{(\coprod_{i\in I}W_i,\prod_{i\in I}\Phi_i)\,|\,(W_i,\Phi_i)\in\mathcal{A}_i\}$? I still don't see how this descends to $E$.
As for the transition functions, these are given by $\phi_i\circ\phi_j^{-1}:U_i\cap U_j\times F\to U_i\cap U_j\times F$, and $(\phi_i\circ\phi_j^{-1})(p,f)=(p,t_{ij}(p)f)$, which are smooth.
• You give each of the $U_i \times F$ the smooth structure of a product. Since the bundle is covered by such things this suffices to define the smooth structure. – user98602 Jun 27 '16 at 18:39
• Does it not matter that you have an infinite product of these? And how does this smooth structure descend to E? – B. Pasternak Jun 27 '16 at 18:41
• Infinite coproduct, aka disjoint union. Just do one at a time. You just need to see that the transition maps are smooth. – user98602 Jun 27 '16 at 18:42
• Please see my edit. – B. Pasternak Jun 27 '16 at 19:00 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9655975103378296, "perplexity": 133.26748192806116}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-30/segments/1563195527204.71/warc/CC-MAIN-20190721205413-20190721231413-00103.warc.gz"} |
https://www.black-holes.org/explore/glossary/30-e/42-epicycle | ## Epicycle
A secondary circle centered on another, usually larger, circle. Its center moves along the circumference of the main circle.
## Inspiration
No amount of experimentation can ever prove me right; a single experiment can prove me wrong.
Albert Einstein | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9073979258537292, "perplexity": 4574.27251803523}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376830305.92/warc/CC-MAIN-20181219005231-20181219031231-00407.warc.gz"} |
http://www.ck12.org/algebra/Write-an-Equation-Given-the-Slope-and-a-Point/enrichment/Writing-Linear-Equations-in-Point-Slope-Form-Given-Information-Overview/r1/ | <img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" />
# Write an Equation Given the Slope and a Point
## Solving y=mx+b for 'b'
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