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There are two main parameters which will determine whether or not any particular interloper can give rise to a significant. effect in terms of Aa/a: column density ane the position in wavelength. with respect to the “host” line of interest. | There are two main parameters which will determine whether or not any particular interloper can give rise to a significant effect in terms of $\da$: column density and the position in wavelength with respect to the `host' line of interest. |
In. order to search for a potential interloper. we explore the range in parameter space through numerica simulation. generating trial interlopers. blended with a single stronger ‘host’ line. and examining the resulting shift in the combined. centroid in terms of λαζα. | In order to search for a potential interloper, we explore the range in parameter space through numerical simulation, generating trial interlopers, blended with a single stronger `host' line, and examining the resulting shift in the combined centroid in terms of $\da$. |
Having establishe the allowed. characteristics of a potential interloper. we use photoionization equilibrium mocels to search for candidate atomic species. | Having established the allowed characteristics of a potential interloper, we use photoionization equilibrium models to search for candidate atomic species. |
We ignore molecular species. | We ignore molecular species. |
We restrict the following discussion to blending with A2796. since Aafa is particularly sensitive to blending with this anchor line in the sample. | We restrict the following discussion to blending with $\lambda$ 2796, since $\da$ is particularly sensitive to blending with this anchor line in the sample. |
We later generalize our discussion to include blending with all other relevan transitions. | We later generalize our discussion to include blending with all other relevant transitions. |
Consider an interloper a spectral line of a blending species .X which is separated from the fitted line centroic wavelength. Ag. by AX (AXAc 0) in the frame of the cloud. | Consider an interloper – a spectral line of a blending species $X$ – which is separated from the fitted line centroid wavelength, $\lambda_0$, by $-\Delta\lambda$ $\Delta\lambda > 0$ ) in the frame of the cloud. |
Let the separation between the actual A2796 wavelength and the fitted line position be dÀ (i.e. dÀτε 0) in the frame of the cloud. | Let the separation between the actual $\lambda$ 2796 wavelength and the fitted line position be $d\lambda$ (i.e. $d\lambda > 0$ ) in the frame of the cloud. |
That is. the line is fit as a single component. despite the presence of the interloper. | That is, the line is fit as a single component, despite the presence of the interloper. |
The interloper has a column density ICX). | The interloper has a column density $N(X)$. |
However. as the species Vis not knownprivrt. we may only determine the quantity NON)fy where fxis the oscillator strength of the interloping transition. | However, as the species $X$ is not known, we may only determine the quantity $N(X)f_X$ where $f_X$is the oscillator strength of the interloping transition. |
We generated a svnthetic optically thin Me A2796 line and matched this against à composite Me A2796. profile which included: an additional weak blended: component. representing our candidate interloper. | We generated a synthetic optically thin Mg $\lambda$ 2796 line and matched this against a composite Mg $\lambda$ 2796 profile which included an additional weak blended component, representing our candidate interloper. |
Phe model was fitted to the ‘data’ usingΡ | The model was fitted to the `data' using. |
ΗΤΗ The svnthetio spectrum. was generated using a column density of 4.1077em.7? and a b- of 5.0kms| as these were representative values for the lines in MOla anc WOL (Churchill 1997). | The synthetic spectrum was generated using a column density of $4
\times 10^{12}{\rm ~cm}^{-2}$ and a $b$ -parameter of $5.0{\rm ~kms}^{-1}$ as these were representative values for the lines in M01a and W01 (Churchill 1997). |
We restricted. the range of f-paramcters for. the interloper using the following physical considerations. | We restricted the range of $b$ -parameters for the interloper using the following physical considerations. |
Hf we consider all lines to be thermally broadened then the. b-parameter varies inversely as the square root of the atomic mass. | If we consider all lines to be thermally broadened then the $b$ -parameter varies inversely as the square root of the atomic mass. |
Any species lighter than Ale will have a larger. b- parameter. | Any species lighter than Mg will have a larger $b$ -parameter. |
Since we are considering .X to have transitions in the ultraviolet. we may assume that it probably. has a mass greater than or comparable to that of Ale. | Since we are considering $X$ to have transitions in the ultraviolet, we may assume that it probably has a mass greater than or comparable to that of Mg. |
We therefore place an upper limit of 6X)<6.0kms|. | We therefore place an upper limit of $b(X) <
6.0{\rm ~kms}^{-1}$. |
Also. we did not consider any species with atomic number greater than ~ 100 and so we adopted a lower limit of b(.N)20.5kms | Also, we did not consider any species with atomic number greater than $\sim$ 100 and so we adopted a lower limit of $b(X) >
0.5{\rm ~kms}^{-1}$. |
ὃν comparing sets of model and synthetic blended lines in this way. we can constrain the range of possible values of αλ. given some apparent afa. | By comparing sets of model and synthetic blended lines in this way, we can constrain the range of possible values of $d\lambda$, given some apparent $\da$. |
We present the results of the simulation in Fig. | We present the results of the simulation in Fig. |
3 where we define Exi=logyNCX)ZNGlgH4)] and. Fx=ogy fx. | 3 where we define $\Gamma_{X,{\rm Mg}{\sc \,ii}} \equiv \log_{10}[N(X)/N({\rm Mg}{\sc
\,ii})]$ and $F_X \equiv \log_{10}f_X$ . |
Phe ripples on the three surface rellect errors (z.0.1dex in Pasar) introduced. due to the restrictive upper limit placed on b(X). | The ripples on the three surface reflect errors $\la 0.1{\rm ~dex}$ in $\Gamma_{X,{\rm Mg}{\sc \,ii}}$ ) introduced due to the restrictive upper limit placed on $b(X)$. |
Using Fig. | Using Fig. |
3. we can now specify a certain value of Aafa (i.c. we specify dA) and an interloping transition of a species X (Le. we specify AA) and find thelower bound on the column density which that species must have in order to rave caused the said shift in Aefe. | 3, we can now specify a certain value of $\da$ (i.e. we specify $d\lambda$ ) and an interloping transition of a species $X$ (i.e. we specify $\Delta\lambda$ ) and find thelower bound on the column density which that species must have in order to have caused the said shift in $\da$. |
For example. if we are concerned with Aafa10 "hen dA—5010TA and the section of Fig. | For example, if we are concerned with $\da \sim 10^{-5}$ then $d\lambda \sim 50
\times 10^{-4}$ and the section of Fig. |
3 with dAx;5010Xcontains information which restricts. the candidateinterlopers. | 3 with $d\lambda \la 50
\times 10^{-4}$contains information which restricts the candidateinterlopers. |
Given a species. .X. what is an upper limit on the column density in any given cloud? | Given a species, $X$ , what is an upper limit on the column density in any given cloud? |
To answer this. we mocdelled the absorption clouds with a grid of models (Ferland 1903). | To answer this, we modelled the absorption clouds with a grid of models (Ferland 1993). |
estimates the photoionization conditions | estimates the photoionization conditions |
Iu this paper we continue our investigations iuto the faint surface brightucss distributions of edec-on ealaxies using data obtained as part of the Beijing-Arizoua-Taipei-ConnecticutQos (BATC) ALulti-Color Survey of Sky (cf. | In this paper we continue our investigations into the faint surface brightness distributions of edge-on galaxies using data obtained as part of the Beijing-Arizona-Taipei-Connecticut (BATC) Multi-Color Survey of Sky (cf. |
Fan et al. | Fan et al. |
1996. Yan ct al. | 1996, Yan et al. |
2000). | 2000). |
In previous papers detailing our investigations of NCC 5907 (Shane ct al. | In previous papers detailing our investigations of NGC 5907 (Shang et al. |
1998: Zheug et al. | 1998; Zheng et al. |
1999). we showed that this galaxy does not have a luminous halo. counter to what was previously suggested (Sackett et al. | 1999), we showed that this galaxy does not have a luminous halo, counter to what was previously suggested (Sackett et al. |
19901: Morrison. Doroson. Harding 1991). | 1994; Morrison, Boroson, Harding 1994). |
Rather. our inuages showed a faint ring around. NCC 5907. likely the result of the tidal disruption of a dwart galaxy. | Rather, our images showed a faint ring around NGC 5907, likely the result of the tidal disruption of a dwarf galaxy. |
The existence of very faint surface briehtuess features around edee-on spiral galaxies is further investigated here with BATC observations of the well-known galaxy NGC 1565. | The existence of very faint surface brightness features around edge-on spiral galaxies is further investigated here with BATC observations of the well-known galaxy NGC 4565. |
As opposed to NGC 5907. NGC 1565 is at high Galactic latitude (86.117). implying that its halo should be less contanunated by bright Galactic stars than are our observations of NGC 5907. | As opposed to NGC 5907, NGC 4565 is at high Galactic latitude $86.44^\circ$ ), implying that its halo should be less contaminated by bright Galactic stars than are our observations of NGC 5907. |
NGC. 1565 as classified as Sb 19913). | NGC 4565 is classified as Sb \cite{RC3}) ). |
We place it at a distance eof 11.5 Apc. based on its distance iu the Mark IIT catalog (1013 kins i: Willicketal. 1996)) and a Ihibble coustant of 72 kins + Mpe| (Freedimanetal.20013). | We place it at a distance of 14.5 Mpc, based on its distance in the Mark III catalog (1043 km $^{-1}$; \cite{Will96}) ) and a Hubble constant of 72 km $^{-1}$ $\rm Mpc^{-1}$ \cite{Freed01}) ). |
It is known to have a Seyfert uucleus (Ilo«tal. L997)). auc has been much studied in the past iu terms of optical surface photometry (Jeuseun&Thuan1982.. hereafter JT: vauderνα1979:: vanderKeuit&Searle 1981.. hereafter KS: Ionueudy&Druzual1978: Tamabeetal. 1980: Nashiud&Jórsáter 1997.. hereafter NJ: Dettinar&Wiclebiuski 1986)). | It is known to have a Seyfert nucleus \cite{Ho97}) ), and has been much studied in the past in terms of optical surface photometry \cite{JT82}, hereafter JT; \cite{K79}; \cite{KS81}, hereafter KS; \cite{KB78}; \cite{H80}; \cite{NJ97}, hereafter NJ; \cite{DW86}) ). |
Most of those earlier sudies were based on photographic data. | Most of those earlier studies were based on photographic data. |
The V-baud data of NJ used a CCD with a relatively stall field of view. making it difficult for them to accurately determine sky backeround levels. | The V-band data of NJ used a CCD with a relatively small field of view, making it difficult for them to accurately determine sky background levels. |
Iufrared J. IT aud I& imaging bx Rice (1996) completes the existing photometric Muaging data on this ealaxy. | Infrared J, H and K imaging by Rice (1996) completes the existing photometric imaging data on this galaxy. |
Our observations and the details of our reduction of the data we have obtained for NGC 1565 are given in Section 2. | Our observations and the details of our reduction of the data we have obtained for NGC 4565 are given in Section 2. |
The measurement of the luminosity profiles auc error analysis are preseuted in Section 3. | The measurement of the luminosity profiles and error analysis are presented in Section 3. |
Mi Section { eives the results of model fitting. comparison and possible svstematic effects from PSF aud disk inchnation. | Section 4 gives the results of model fitting, comparison and possible systematic effects from PSF and disk inclination. |
The lIast section sunuuiauizcSs the main results of this paper. | The last section summarizes the main results of this paper. |
Observations of NGC [565 were otained with the 60/9060 Schmidt telescope at he Nineglong Station of the National Astronomy Observatories of China (NOAC). using a thick Ford 2018« CCD with 15 jn pixels at the £/3 prine focus. | Observations of NGC 4565 were obtained with the 60/90cm Schmidt telescope at the Xinglong Station of the National Astronomy Observatories of China (NOAC), using a thick Ford $\rm 2048\times2048$ CCD with 15 m pixels at the f/3 prime focus. |
The field of view of this CCD is 58&58% and the sca eis L7" /pixel. | The field of view of this CCD is $58' \times 58'$ and the scale is $''$ /pixel. |
With the nearly one degree field of view. there is sufficient skv iu a sinele frame such that «)bjects with visual sizes less than 30’ can have their «kx ekeround deteriined accurately. | With the nearly one degree field of view, there is sufficient sky in a single frame such that objects with visual sizes less than $'$ can have their sky background determined accurately. |
The Lick daa-taking svstena ds eniployed and all the CCD images are overscan-ubtracted (.c.. mitially bias-subtracted) diving the readout | The Lick data-taking system is employed and all the CCD images are overscan-subtracted (i.e., initially bias-subtracted) during the readout |
Interestingly. several studies (e.g. Maiolino et al. | Interestingly, several studies (e.g. Maiolino et al. |
2004) show that the extinction. curve in high redshift QSOs is similar to the one expected for a medium dominated by SN dust. | 2004) show that the extinction curve in high redshift QSOs is similar to the one expected for a medium dominated by SN dust. |
Indeed. some SNell (and possibly “prompt” SNela. see Mannucci et al. 2006) can provide the metal seeds out of which the QSO dust can condense. | Indeed, some SNeII (and possibly “prompt” SNeIa, see Mannucci et al, 2006) can provide the metal seeds out of which the QSO dust can condense. |
The effect of the QSO dust amount and composition on the spectral properties of high redshift spheroids can possibly constrain the above scheme and it will be the topic of a forthcoming paper. | The effect of the QSO dust amount and composition on the spectral properties of high redshift spheroids can possibly constrain the above scheme and it will be the topic of a forthcoming paper. |
From the discovery of LBGs (see Steidel et al. | From the discovery of LBGs (see Steidel et al. |
1996a.b). only a handful of objects whose abundance pattern has been studied in great detail. | 1996a,b), only a handful of objects whose abundance pattern has been studied in great detail. |
One of the first of such objects for which abundance measurements were available is MS 1512-cB58. studied by Pettini et al. ( | One of the first of such objects for which abundance measurements were available is MS 1512-cB58, studied by Pettini et al. ( |
2002). | 2002). |
Owing to its. gravitationally lensed nature. MS 1512-cB58 is one of the brightest known LBGs. | Owing to its gravitationally lensed nature, MS 1512-cB58 is one of the brightest known LBGs. |
This object is at z~2.73 and has a luminous mass of 10?M... a star formation rate Wry)~30M.yr! (Pettinietal..2002) and an effective radius of rj~2kpe (Seitz et al. | This object is at $z \sim 2.73$ and has a luminous mass of $\sim 10^{10}M_{\odot}$, a star formation rate $\psi (t_{sf})\sim 40 \,\rm M_{\odot}yr^{-1}$ \citep{pettini02_cb58} and an effective radius of $r_{L}\sim 2 \rm \, kpc$ (Seitz et al. |
1998). for à Q,,=0.3.040.1.10.70 cosmology. | 1998), for a $\Omega_m= 0.3,\Omega_{\Lambda}=0.7, h=0.70$ cosmology. |
Pettini et al. ( | Pettini et al. ( |
2002) concluded that the abundances of O. Mg and Si are ~2/5 of their solar values. whereas This underabundance i$. probably caused by depletion into dust. | 2002) concluded that the abundances of O, Mg and Si are $\sim 2/5$ of their solar values, whereas This underabundance is probably caused by depletion into dust. |
Pettini et al. ( | Pettini et al. ( |
2002) took into account the effect of dust depletion on Fe-peak elements anc suggested that is of the order of a factor of two. | 2002) took into account the effect of dust depletion on Fe-peak elements and suggested that is of the order of a factor of two. |
Matteucci Pipino (2002) modeled the chemical abundances of such a galaxy by taking into account the dust depletion. as suggested by Pettini et al. ( | Matteucci Pipino (2002) modeled the chemical abundances of such a galaxy by taking into account the dust depletion, as suggested by Pettini et al. ( |
2002) and concluded that this galaxy is a small young elliptical undergoing a burst of star formation anc a galactic wind. | 2002) and concluded that this galaxy is a small young elliptical undergoing a burst of star formation and a galactic wind. |
We suggested an age of 35 Myr for this object. | We suggested an age of 35 Myr for this object. |
However. that original formulation of the chemical evolutior model did not take into account the dust evolution as we have here. | However, that original formulation of the chemical evolution model did not take into account the dust evolution as we have here. |
Further confirmation of the presence of the dust came from 3D Lye transfer models (Schaerer&Verhamme.2008) and dust emission models (Takeuchi&Ishi.2004). | Further confirmation of the presence of the dust came from 3D $Ly{\alpha}$ transfer models \citep{3dly_lbg} and dust emission models \citep{dust_em_lbg}. |
More recently. other lensed LBGs have been observed (e.g.. Quider et al.. | More recently, other lensed LBGs have been observed (e.g., Quider et al., |
2009. 2010. Dessauges-Zavadsky et al.. | 2009, 2010, Dessauges-Zavadsky et al., |
2010) but the presence of either line emission or intervening systems. as well as the different spectral coverage. hampered | 2010) but the presence of either line emission or intervening systems, as well as the different spectral coverage, hampered |
binary svstem. | binary system. |
We suggest that the major Huctuations in the brightness of the star are due to events of intense accretion [rom " giant star onto its hot companion. | We suggest that the major fluctuations in the brightness of the star are due to events of intense accretion from the giant star onto its hot companion. |
Between 1889 and pu) Mthese events took place periodically with a period of 131: binary After 1972. they are occurring in the system at the orbital frequency. | Between 1889 and 1940 these events took place periodically with a period of 1373 d. After 1972, they are occurring in the system at the binary orbital frequency. |
We acknowledge with thanks the variable star observations from the AAVSO International Database. contributed by observers worldwide and used in this research. | We acknowledge with thanks the variable star observations from the AAVSO International Database contributed by observers worldwide and used in this research. |
We also thank an anonvmous referee for comments that enable considerable iniprovements in some parts of the paper. | We also thank an anonymous referee for comments that enable considerable improvements in some parts of the paper. |
This research is supported. by LSE - Israel Science Foundation of the Isracli Acacemy of Sciences. | This research is supported by ISF - Israel Science Foundation of the Israeli Academy of Sciences. |
(Ixaaretetal2001:Matsuuotoαἱ,2001: >1079 10AZ,<API0AF, (Colbert&XNushotzkyvishimaetal.2000) (INauu | \citep{Kaa01,Mat01,Zez02}, $> 10^{39}$ $10 \, M_\odot\! < \! M \! <\! 10^5
\,M_\odot$ \citep{Col99,Mak00}
\citep{Kaa01}. |
etctal,2OL).. Miley(2005). | \cite{Mil04} \cite{Mil05}. |
. (sineefef.2001)... (Beechuan2002) is bezuned from a ecometrically thick accretion disk (singcfal;2001). | \citep{Por02,Tan00,Mad01} \citep{Kin01}, \citep{Beg02} is beamed from a geometrically thick accretion disk \citep{Kin01}. |
. For the latter case. it has been argued that such thick "fuuucl shaped disks cuhance the observed flux bv just a factor of few (Misra&Syrian2003). | For the latter case, it has been argued that such thick "funnel" shaped disks enhance the observed flux by just a factor of few \citep{Mis03}. |
. Thus. it is important to ascertain whether ULX do indeed harbor IMDII or not. | Thus, it is important to ascertain whether ULX do indeed harbor IMBH or not. |
Since a more clirect measure of the lass such as spectroscopic mass function measurement of the binary. is nof possible for ULNA. indirect evidences have to be used. | Since a more direct measure of the mass such as spectroscopic mass function measurement of the binary, is not possible for ULX, indirect evidences have to be used. |
οre such wav is to look for simularitices iu the spectral and temporal properties of ULX aud black hole N-rav binaries. | One such way is to look for similarities in the spectral and temporal properties of ULX and black hole X-ray binaries. |
There are theoretica indications that the natire of the accretion flow shotld dejud on the Eddinet«n ratio L/L,dq rather than o ithe actual values of the leylometiic huninosity £ aud the Eddineton μπιτ Lrag. | There are theoretical indications that the nature of the accretion flow should depend on the Eddington ratio $L/L_{edd} $ rather than on the actual values of the bolometric luminosity $L$ and the Eddington limit $L_{Edd}$. |
Thus. à ULX should displav siwilar spectral aud temporal charactcristics as a black role N-rav binary accreting at a simular {πιω even thoieh the masses of the black holes are cliffereut. | Thus, a ULX should display similar spectral and temporal characteristics as a black hole X-ray binary accreting at a similar $L/L_{Edd}$, even though the masses of the black holes are different. |
Tf ULX harbor IMDBIT. they should disday analogues spectral states to N-rav binaries. | If ULX harbor IMBH, they should display analogues spectral states to X-ray binaries. |
Based on such a analogy. Yuanetal.(2007) modeled t1ο X-ray spectra detected by of the ULN X-1 i1 M82, within he framework of Advection Dominated Accreion Flows (ADAF) which successfully explains the hard state spectra of N-vav binaries. | Based on such a analogy, \cite{Yua07} modeled the X-ray spectrum detected by of the ULX X-1 in M82, within the framework of Advection Dominated Accretion Flows (ADAF) which successfully explains the hard state spectra of X-ray binaries. |
They found that if he source is likened to the low-huuinosity hard state then the black role dass should be AF~LOPAL, else it should be LOLAL.. if the system is to be compared wit1 the high muinosity hard state. | They found that if the source is likened to the low-luminosity hard state then the black hole mass should be $M \sim 10^5 M_\odot$ else it should be $\sim 10^4 M_\odot$ if the system is to be compared with the high luminosity hard state. |
This degeneracy occurs because he observed spectrum duriug au off axis «ervation wo { the source is affected bv. couif pile-up Or normal observations) was a featureless )owoer-Iwnw as it should be if it is analogues to the hard state. | This degeneracy occurs because the observed spectrum during an off axis observation by ( the source is affected by count pile-up for normal observations) was a featureless power-law as it should be if it is analogues to the hard state. |
XMM observations of the source reveal a more complex urnover at around ~8 keV (Aerawal&Misra 2006).. which could either be because the spectral statewas | XMM observations of the source reveal a more complex turnover at around $\sim 8$ keV \citep{Agr06}, , which could either be because the spectral statewas |
lens approaches the source. | lens approaches the source. |
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