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| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0707.0530 | Hideki Maeda | Hideki Maeda, Tomohiro Harada and B.J. Carr | Self-similar cosmological solutions with dark energy. II: black holes,
naked singularities and wormholes | 12 pages, 19 figures, 1 table, final version to appear in Physical
Review D | Phys.Rev.D77:024023,2008 | 10.1103/PhysRevD.77.024023 | CECS-PHY-07/16 | gr-qc astro-ph hep-th | null | We use a combination of numerical and analytical methods, exploiting the
equations derived in a preceding paper, to classify all spherically symmetric
self-similar solutions which are asymptotically Friedmann at large distances
and contain a perfect fluid with equation of state $p=(\gamma -1)\mu$ with
$0<\gamma<2/3$. The expansion of the Friedmann universe is accelerated in this
case. We find a one-parameter family of self-similar solutions representing a
black hole embedded in a Friedmann background. This suggests that, in contrast
to the positive pressure case, black holes in a universe with dark energy can
grow as fast as the Hubble horizon if they are not too large. There are also
self-similar solutions which contain a central naked singularity with negative
mass and solutions which represent a Friedmann universe connected to either
another Friedmann universe or some other cosmological model. The latter are
interpreted as self-similar cosmological white hole or wormhole solutions. The
throats of these wormholes are defined as two-dimensional spheres with minimal
area on a spacelike hypersurface and they are all non-traversable because of
the absence of a past null infinity.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 02:42:46 GMT"
},
{
"version": "v2",
"created": "Sat, 6 Oct 2007 02:02:37 GMT"
},
{
"version": "v3",
"created": "Wed, 2 Jan 2008 19:02:25 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Maeda",
"Hideki",
""
],
[
"Harada",
"Tomohiro",
""
],
[
"Carr",
"B. J.",
""
]
] |
0707.0531 | Daun Jeong | Daun Jeong, M.Y. Choi, Hyunggyu Park | Construction of equilibrium networks with an energy function | To appear in J. Phys. A | null | 10.1088/1751-8113/40/32/001 | null | cond-mat.stat-mech | null | We construct equilibrium networks by introducing an energy function depending
on the degree of each node as well as the product of neighboring degrees. With
this topological energy function, networks constitute a canonical ensemble,
which follows the Boltzmann distribution for given temperature. It is observed
that the system undergoes a topological phase transition from a random network
to a star or a fully-connected network as the temperature is lowered. Both
mean-field analysis and numerical simulations reveal strong first-order phase
transitions at temperatures which decrease logarithmically with the system
size. Quantitative discrepancies of the simulation results from the mean-field
prediction are discussed in view of the strong first-order nature.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 02:51:31 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Jeong",
"Daun",
""
],
[
"Choi",
"M. Y.",
""
],
[
"Park",
"Hyunggyu",
""
]
] |
0707.0532 | Mirjana Vuleti\'c | Mirjana Vuleti\'c | A generalization of MacMahon's formula | 19 pages, 5 figures | Trans. Amer. Math. Soc. 361 (2009), 2789-2804 | null | null | math.CO math-ph math.MP | null | We generalize the generating formula for plane partitions known as MacMahon's
formula as well as its analog for strict plane partitions. We give a
2-parameter generalization of these formulas related to Macdonald's symmetric
functions. The formula is especially simple in the Hall-Littlewood case. We
also give a bijective proof of the analog of MacMahon's formula for strict
plane partitions.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 03:06:43 GMT"
}
] | 2009-03-11T00:00:00 | [
[
"Vuletić",
"Mirjana",
""
]
] |
0707.0533 | Hiroto Kuninaka | Hiroto Kuninaka and Hisao Hayakawa | Super-elastic collisions in a thermally activated system | 4 pages, 5 figures, submitted to Prog. Theor. Phys. Suppl. as a
proceeding of "Symposium on the 50th anniversary of Alder transition" (2007,
http://stat.system.nitech.ac.jp/Alder50/) | Prog. Theor. Phys. No.178, 157-162 (2009). | 10.1143/PTPS.178.157 | null | cond-mat.stat-mech | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Impact phenomena of small clusters subject to thermal fluctuations are
numerically investigated. From the molecular dynamics simulation for colliding
two identical clusters, it is found that the restitution coefficient for
head-on collisions can exceed unity when the colliding speed is smaller than
the thermal velocity of one ``atom'' of the clusters. The averaged behavior can
be understood by the quasi-static theory of impact phenomena. It is also
confirmed that our result is governed by the fluctuation theorem.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 03:18:41 GMT"
},
{
"version": "v2",
"created": "Thu, 31 Jul 2008 03:16:39 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Kuninaka",
"Hiroto",
""
],
[
"Hayakawa",
"Hisao",
""
]
] |
0707.0534 | Zuo-Tang Liang | Ye Chen, Zuo-tang Liang, Ernst Sichtermann, Qing-hua Xu and Shan-shan
Zhou | Anti-Hyperon polarization in high energy pp collisions with polarized
beams | 17 pages, 9 figures,version to appear in PRD | Phys.Rev.D78:054007,2008 | 10.1103/PhysRevD.78.054007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the longitudinal polarization of the Sigma_bar and Xi_bar
anti-hyperons in polarized high energy pp collisions at large transverse
momenta, extending a recent study for the Lambda_bar anti-hyperon. We make
predictions by using different parametrizations of the polarized parton
densities and models for the polarized fragmentation functions. Similar to the
Lambda_bar polarization, the Xi_bar0 and Xi_bar+ polarizations are found to be
sensitive to the polarized anti-strange sea in the nucleon. The Sigma_bar- and
Sigma_bar+ polarizations show sensitivity to the light sea quark polarizations,
\Delta \bar u(x) and \Delta \bar d(x), and their asymmetry.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 04:11:58 GMT"
},
{
"version": "v2",
"created": "Sun, 31 Aug 2008 06:33:58 GMT"
}
] | 2009-01-09T00:00:00 | [
[
"Chen",
"Ye",
""
],
[
"Liang",
"Zuo-tang",
""
],
[
"Sichtermann",
"Ernst",
""
],
[
"Xu",
"Qing-hua",
""
],
[
"Zhou",
"Shan-shan",
""
]
] |
0707.0535 | Naoki Seto | Naoki Seto, Atsushi Taruya | Measuring a Parity Violation Signature in the Early Universe via
Ground-based Laser Interferometers | 6 pages, 3 figures, accepted for publication in PRL | Phys.Rev.Lett.99:121101,2007 | 10.1103/PhysRevLett.99.121101 | UTAP-576, RESCEU-3/07 | astro-ph gr-qc | null | We show that pairs of widely separated interferometers are advantageous for
measuring the Stokes parameter V of a stochastic background of gravitational
waves. This parameter characterizes asymmetry of amplitudes of right- and
left-handed waves and generation of the asymmetry is closely related to parity
violation in the early universe. The advantageous pairs include
LIGO(Livingston)-LCGT and AIGO-Virgo that are relatively insensitive to
Omega_GW (the simple intensity of the background). Using at least three
detectors, information of the intensity Omega_GW and the degree of asymmetry V
can be separately measured.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 04:14:02 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Seto",
"Naoki",
""
],
[
"Taruya",
"Atsushi",
""
]
] |
0707.0536 | Etienne Roquain | Gilles Blanchard (FIRST.IDA), Etienne Roquain (LPMA) | Adaptive FDR control under independence and dependence | null | null | null | null | math.ST stat.TH | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the context of multiple hypotheses testing, the proportion $\pi_0$ of true
null hypotheses in the pool of hypotheses to test often plays a crucial role,
although it is generally unknown a priori. A testing procedure using an
implicit or explicit estimate of this quantity in order to improve its
efficency is called adaptive. In this paper, we focus on the issue of False
Discovery Rate (FDR) control and we present new adaptive multiple testing
procedures with control of the FDR. First, in the context of assuming
independent $p$-values, we present two new procedures and give a unified review
of other existing adaptive procedures that have provably controlled FDR. We
report extensive simulation results comparing these procedures and testing
their robustness when the independence assumption is violated. The new proposed
procedures appear competitive with existing ones. The overall best, though, is
reported to be Storey's estimator, but for a parameter setting that does not
appear to have been considered before. Second, we propose adaptive versions of
step-up procedures that have provably controlled FDR under positive dependences
and unspecified dependences of the $p$-values, respectively. While simulations
only show an improvement over non-adaptive procedures in limited situations,
these are to our knowledge among the first theoretically founded adaptive
multiple testing procedures that control the FDR when the $p$-values are not
independent.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 04:44:45 GMT"
},
{
"version": "v2",
"created": "Tue, 8 Apr 2008 14:37:49 GMT"
},
{
"version": "v3",
"created": "Tue, 17 Feb 2009 12:58:57 GMT"
}
] | 2009-02-17T00:00:00 | [
[
"Blanchard",
"Gilles",
"",
"FIRST.IDA"
],
[
"Roquain",
"Etienne",
"",
"LPMA"
]
] |
0707.0537 | Valentine Genon-Catalot | Mireille Chaleyat-Maurel (MAP5, PMA), Valentine Genon-Catalot (MAP5) | Filtering the Wright-Fisher diffusion | 24 pages | null | null | null | math.PR | null | We consider a Wright-Fisher diffusion (x(t)) whose current state cannot be
observed directly. Instead, at times t1 < t2 < . . ., the observations y(ti)
are such that, given the process (x(t)), the random variables (y(ti)) are
independent and the conditional distribution of y(ti) only depends on x(ti).
When this conditional distribution has a specific form, we prove that the model
((x(ti), y(ti)), i 1) is a computable filter in the sense that all
distributions involved in filtering, prediction and smoothing are exactly
computable. These distributions are expressed as finite mixtures of parametric
distributions. Thus, the number of statistics to compute at each iteration is
finite, but this number may vary along iterations.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 04:45:44 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Chaleyat-Maurel",
"Mireille",
"",
"MAP5, PMA"
],
[
"Genon-Catalot",
"Valentine",
"",
"MAP5"
]
] |
0707.0538 | Ken-iti Sato | Ken-iti Sato | Transformations of infinitely divisible distributions via improper
stochastic integrals | 44 pages | null | null | null | math.PR | null | Let $X^{(\mu)}(ds)$ be an $\mathbb{R}^d$-valued homogeneous independently
scattered random measure over $\mathbb{R}$ having $\mu$ as the distribution of
$X^{(\mu)}((t,t+1])$. Let $f(s)$ be a nonrandom measurable function on an open
interval $(a,b)$ where $-\infty\leqslant a<b\leqslant\infty$. The improper
stochastic integral $\int_{a+}^{b-} f(s)X^{(\mu)}(ds)$ is studied. Its
distribution $\Phi_f(\mu)$ defines a mapping from $\mu$ to an infinitely
divisible distribution on $\mathbb{R}^d$. Three modifications (compensated,
essential, and symmetrized) and absolute definability are considered. After
their domains are characterized, necessary and sufficient conditions for the
domains to be very large (or very small) in various senses are given. The
concept of the dual in the class of purely non-Gaussian infinitely divisible
distributions on $\mathbb{R}^d$ is introduced and employed in studying some
examples. The $\tau$-measure $\tau$ of function $f$ is introduced and whether
$\tau$ determines $\Phi_f$ is discussed. Related transformations of L\'evy
measures are also studied.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 04:59:37 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Sato",
"Ken-iti",
""
]
] |
0707.0539 | Naoko Iida | N. Iida, J. Flanagan, Y. Funakoshi and K. Oide | Synchrotron Radiation Interferometer Calibration Check by Use of A Size
Control Bump in KEKB | 3 pages, 4 figures, Particle Accelerator Conference 07, Albuquerque | null | null | null | physics.acc-ph | null | In KEKB, synchrotron radiation interferometers (SRMs) are used for measuring
the transverse beam sizes. There is also a tool for enlarging the vertical beam
size intentionally by making an asymmetric bump, called an ``iSize'' bump, at
one of the strongest non-interleaved sextupole magnets in each KEKB ring. The
calibrations of the SRMs were checked by comparing the measured vertical beam
sizes with those calculated using the computer code ``SAD''. The obtained
correction factors are 1.000$\pm$0.045 for HER and 0.971$\pm$0.060 for LER,
which are consistent with the calibration factors of SRMs\cite{SRMcalib} within
errors. Using the obtained calibration factor, x-y coupling of each ring was
calculated .
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 05:07:28 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Iida",
"N.",
""
],
[
"Flanagan",
"J.",
""
],
[
"Funakoshi",
"Y.",
""
],
[
"Oide",
"K.",
""
]
] |
0707.0540 | Tao Zhou | Tao Zhou, Jie Ren, Matus Medo, Yi-Cheng Zhang | How to project a bipartite network? | 7 pages, 4 figures | Physical Review E 76, 046115 (2007) | 10.1103/PhysRevE.76.046115 | null | physics.soc-ph physics.data-an | null | The one-mode projecting is extensively used to compress the bipartite
networks. Since the one-mode projection is always less informative than the
bipartite representation, a proper weighting method is required to better
retain the original information. In this article, inspired by the network-based
resource-allocation dynamics, we raise a weighting method, which can be
directly applied in extracting the hidden information of networks, with
remarkably better performance than the widely used global ranking method as
well as collaborative filtering. This work not only provides a creditable
method in compressing bipartite networks, but also highlights a possible way
for the better solution of a long-standing challenge in modern information
science: How to do personal recommendation?
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 05:09:34 GMT"
},
{
"version": "v2",
"created": "Tue, 31 Jul 2007 20:28:21 GMT"
}
] | 2011-11-10T00:00:00 | [
[
"Zhou",
"Tao",
""
],
[
"Ren",
"Jie",
""
],
[
"Medo",
"Matus",
""
],
[
"Zhang",
"Yi-Cheng",
""
]
] |
0707.0541 | In-Ok Song | In-Ok Song, J. McCombie, T.H. Kerr and P.J. Sarre | The 3.3 $\mu$m PAH emission band of the Red Rectangle | 8 pages, 12 figures, MNRAS accepted | null | 10.1111/j.1365-2966.2007.12197.x | null | astro-ph | null | A new analysis of long-slit CGS4 (UKIRT) spectra of the 3.3 $\mu$m feature of
the Red Rectangle and its evolution with offset along the NW whisker of the
nebula is presented. The results support a proposed two-component
interpretation for the 3.3 $\mu$m feature with peak wavelengths near 3.28
$\mu$m and 3.30 $\mu$m. Both components exhibit a small shift to shorter
wavelength with increasing offset from the central star which, by comparison
with laboratory studies, is consistent with a decrease in temperature of the
carriers with distance from HD 44179. The two-component approach is also
applied to 3.3 $\mu$m data for the Red Rectangle, Orion Bar D2 and Orion Bar
H2S1 from ISO SWS studies.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 05:30:49 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Song",
"In-Ok",
""
],
[
"McCombie",
"J.",
""
],
[
"Kerr",
"T. H.",
""
],
[
"Sarre",
"P. J.",
""
]
] |
0707.0542 | Wang Wei | W. Wang (1), X.-W. Liu (1 and 2) ((1) Department of Astronomy, Peking
University, Beijing, China (2) Kavli Institute for Astronomy and
Astrophysics, Peking University, Beijing China) | Elemental abundances of Galactic bulge planetary nebulae from optical
recombination lines | 35 pages, 27 figures and 16 tables, accepted for publication in MNRAS | null | 10.1111/j.1365-2966.2007.12198.x | null | astro-ph | null | (abridged) Deep long-slit optical spectrophotometric observations are
presented for 25 Galactic bulge planetary nebulae (GBPNe) and 6 Galactic disk
planetary nebulae (GDPNe). The spectra, combined with archival ultraviolet
spectra obtained with the International Ultraviolet Explorer (IUE) and infrared
spectra obtained with the Infrared Space Observatory (ISO), have been used to
carry out a detailed plasma diagnostic and element abundance analysis utilizing
both collisional excited lines (CELs) and optical recombination lines (ORLs).
Comparisons of plasma diagnostic and abundance analysis results obtained from
CELs and from ORLs reproduce many of the patterns previously found for GDPNe.
In particular we show that the large discrepancies between electron
temperatures (Te's) derived from CELs and from ORLs appear to be mainly caused
by abnormally low values yielded by recombination lines and/or continua.
Similarly, the large discrepancies between heavy element abundances deduced
from ORLs and from CELs are largely caused by abnormally high values obtained
from ORLs, up to tens of solar in extreme cases. It appears that whatever
mechanisms are causing the ubiquitous dichotomy between CELs and ORLs, their
main effects are to enhance the emission of ORLs, but hardly affect that of
CELs. It seems that heavy element abundances deduced from ORLs may not reflect
the bulk composition of the nebula. Rather, our analysis suggests that ORLs of
heavy element ions mainly originate from a previously unseen component of
plasma of Te's of just a few hundred Kelvin, which is too cool to excite any
optical and UV CELs.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 05:44:16 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wang",
"W.",
"",
"1 and 2"
],
[
"Liu",
"X. -W.",
"",
"1 and 2"
]
] |
0707.0543 | Tomohiro Matsuda | Tomohiro Matsuda | Cosmological perturbations from inhomogeneous preheating and multi-field
trapping | 18pages, 2 figures, to appear in JHEP | JHEP0707:035,2007 | 10.1088/1126-6708/2007/07/035 | null | hep-th astro-ph hep-ph | null | We consider inhomogeneous preheating in a multi-field trapping model. The
curvature perturbation is generated by inhomogeneous preheating which induces
multi-field trapping at the enhanced symmetric point (ESP), and results in
fluctuation in the number of e-foldings. Instead of considering simple
reheating after preheating, we consider a scenario of shoulder inflation
induced by the trapping. The fluctuation in the number of e-foldings is
generated during this weak inflationary period, when the additional light
scalar field is trapped at the local maximum of its potential. The situation
may look similar to locked or thermal inflation or even to hybrid inflation,
but we will show that the present mechanism of generating the curvature
perturbation is very different from these others. Unlike the conventional
trapped inflationary scenario, we do not make the assumption that an ESP
appears at some unstable point on the inflaton potential. This assumption is
crucial in the original scenario, but it is not important in the multi-field
model. We also discuss inhomogeneous preheating at late-time oscillation, in
which the magnitude of the curvature fluctuation can be enhanced to accommodate
low inflationary scale.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 06:04:08 GMT"
},
{
"version": "v2",
"created": "Wed, 11 Jul 2007 04:31:02 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Matsuda",
"Tomohiro",
""
]
] |
0707.0544 | Qingzhong Liu | Q.Z. Liu, J. van Paradijs, and E.P.J. van den Heuvel | A catalogue of low-mass X-ray binaries in the Galaxy, LMC, and SMC
(Fourth edition) | 45 pages, catalogue included | Astron.Astrophys.469:807,2007 | 10.1051/0004-6361:20077303 | null | astro-ph | null | We present a new edition of the catalogue of the low-mass X-ray binaries in
the Galaxy and the Magellanic Clouds. The catalogue contains source name(s),
coordinates, finding chart, X-ray luminosity, system parameters, and stellar
parameters of the components and other characteristic properties of 187
low-mass X-ray binaries, together with a comprehensive selection of the
relevant literature. The aim of this catalogue is to provide the reader with
some basic information on the X-ray sources and their counterparts in other
wavelength ranges ($\gamma$-rays, UV, optical, IR, and radio). Some sources,
however, are only tentatively identified as low-mass X-ray binaries on the
basis of their X-ray properties similar to the known low-mass X-ray binaries.
Further identification in other wavelength bands is needed to finally determine
the nature of these sources. In cases where there is some doubt about the
low-mass nature of the X-ray binary this is mentioned. Literature published
before 1 October 2006 has, as far as possible, been taken into account.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 06:41:45 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Liu",
"Q. Z.",
""
],
[
"van Paradijs",
"J.",
""
],
[
"Heuvel",
"E. P. J. van den",
""
]
] |
0707.0545 | Tsunehiko Kato | Tsunehiko N. Kato | Relativistic Collisionless Shocks in Unmagnetized Electron-Positron
Plasmas | 6 pages, 13 figures. Accepted for publication in The Astrophysical
Journal | Astrophys.J. 668 (2007) 974-979 | 10.1086/521297 | null | astro-ph | null | It is shown that collisionless shock waves can be driven in unmagnetized
electron-positron plasmas by performing a two-dimensional particle-in-cell
simulation. At the shock transition region, strong magnetic fields are
generated by a Weibel-like instability. The generated magnetic fields are
strong enough to deflect the incoming particles from upstream of the shock at a
large angle and provide an effective dissipation mechanism for the shock. The
structure of the collisionless shock propagates at an almost constant speed.
There is no linear wave corresponding to the shock wave and therefore this can
be regarded as a kind of ``instability-driven'' shock wave. The generated
magnetic fields rapidly decay in the downstream region. It is also observed
that a fraction of the thermalized particles in the downstream region return
upstream through the shock transition region. These particles interact with the
upstream incoming particles and cause the generation of charge-separated
current filaments in the upstream of the shock as well as the electrostatic
beam instability. As a result, electric and magnetic fields are generated even
upstream of the shock transition region. No efficient acceleration processes of
particles were observed in our simulation.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 07:02:00 GMT"
}
] | 2008-03-31T00:00:00 | [
[
"Kato",
"Tsunehiko N.",
""
]
] |
0707.0546 | Juli\'an Mestre | Juli\'an Mestre | Weighted Popular Matchings | 14 pages, 3 figures. A preliminary version appeared in the
Proceedings of the 33rd International Colloquium on Automata, Languages and
Programming (ICALP) | null | null | null | cs.DS | null | We study the problem of assigning jobs to applicants. Each applicant has a
weight and provides a preference list ranking a subset of the jobs. A matching
M is popular if there is no other matching M' such that the weight of the
applicants who prefer M' over M exceeds the weight of those who prefer M over
M'. This paper gives efficient algorithms to find a popular matching if one
exists.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 06:55:43 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Mestre",
"Julián",
""
]
] |
0707.0547 | Kazuhiko Kurano | Kazuhiko Kurano (Meiji University) and Vasudevan Srinivas (Tata
Institute) | A local ring such that the map between Grothendieck groups with rational
coefficient induced by completion is not injective | 15pages | null | null | null | math.AC math.KT | null | In this paper, we construct a local ring $A$ such that the kernel of the map
$G_0(A)\subq \to G_0(\hat{A})\subq$ is not zero, where $\hat{A}$ is the
comletion of $A$ with respect to the maximal ideal, and $G_0()\subq$ is the
Grothendieck group of finitely generated modules with rational coefficient. In
our example, $A$ is a two-dimensional local ring which is essentially of finite
type over ${\Bbb C}$, but it is not normal.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 06:56:33 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Kurano",
"Kazuhiko",
"",
"Meiji University"
],
[
"Srinivas",
"Vasudevan",
"",
"Tata\n Institute"
]
] |
0707.0548 | Sebastien Verel | Michael Defoin Platel (I3S), Sebastien Verel (I3S), Manuel Clergue
(I3S), Philippe Collard (I3S) | From Royal Road to Epistatic Road for Variable Length Evolution
Algorithm | null | Lecture notes in computer science (Lect. notes comput. sci.) ISSN
0302-9743 (27/10/2003) 3-14 | null | null | cs.NE | null | Although there are some real world applications where the use of variable
length representation (VLR) in Evolutionary Algorithm is natural and suitable,
an academic framework is lacking for such representations. In this work we
propose a family of tunable fitness landscapes based on VLR of genotypes. The
fitness landscapes we propose possess a tunable degree of both neutrality and
epistasis; they are inspired, on the one hand by the Royal Road fitness
landscapes, and the other hand by the NK fitness landscapes. So these
landscapes offer a scale of continuity from Royal Road functions, with
neutrality and no epistasis, to landscapes with a large amount of epistasis and
no redundancy. To gain insight into these fitness landscapes, we first use
standard tools such as adaptive walks and correlation length. Second, we
evaluate the performances of evolutionary algorithms on these landscapes for
various values of the neutral and the epistatic parameters; the results allow
us to correlate the performances with the expected degrees of neutrality and
epistasis.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 06:57:52 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Platel",
"Michael Defoin",
"",
"I3S"
],
[
"Verel",
"Sebastien",
"",
"I3S"
],
[
"Clergue",
"Manuel",
"",
"I3S"
],
[
"Collard",
"Philippe",
"",
"I3S"
]
] |
0707.0549 | Qingzhong Liu | Q.Z. Liu, J. van Paradijs, and E.P.J. van den Heuvel | Catalogue of high-mass X-ray binaries in the Galaxy ($4^{th}$ edition) | 25 pages, table included | Astron.Astrophys.455:1165,2006 | 10.1051/0004-6361:20064987 | null | astro-ph | null | We present a new edition of the catalogue of high-mass X-ray binaries in the
Galaxy. The catalogue contains source name(s), coordinates, finding chart,
X-ray luminosity, system parameters, and stellar parameters of the components
and other characteristic properties of 114 high-mass X-ray binaries, together
with a comprehensive selection of the relevant literature. The aim of this
catalogue is to provide the reader with some basic information on the X-ray
sources and their counterparts in other wavelength ranges ($\gamma$-rays, UV,
optical, IR, radio). About 60% of the high-mass X-ray binary candidates are
known or suspected Be/X-ray binaries, while 32% are supergiant/X-ray binaries.
Some sources, however, are only tentatively identified as high-mass X-ray
binaries on the basis of their X-ray properties similar to the known high-mass
X-ray binaries. Further identification in other wavelength bands is needed to
finally determine the nature of these sources. In cases where there is some
doubt about the high-mass nature of the X-ray binary this is mentioned.
Literature published before 1 October 2005 has, as far as possible, been taken
into account.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 07:02:15 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Liu",
"Q. Z.",
""
],
[
"van Paradijs",
"J.",
""
],
[
"Heuvel",
"E. P. J. van den",
""
]
] |
0707.0550 | Martin C. Smith | Martin C. Smith (1), Przemyslaw Wozniak (2), Shude Mao (3), Takahiro
Sumi (4,5) ((1) Kapteyn Astronomical Institute; (2) Los Alamos National
Laboratory; (3) Univ. of Manchester; (4) Princeton University Observatory;
(5) Nagoya University) | Blending in Gravitational Microlensing Experiments: Source Confusion And
Related Systematics | 18 pages, 10 figures. MNRAS (in press) | null | 10.1111/j.1365-2966.2007.12130.x | null | astro-ph | null | Gravitational microlensing surveys target very dense stellar fields in the
local group. As a consequence the microlensed source stars are often blended
with nearby unresolved stars. The presence of `blending' is a cause of major
uncertainty when determining the lensing properties of events towards the
Galactic centre. After demonstrating empirical cases of blending we utilize
Monte Carlo simulations to probe the effects of blending. We generate
artificial microlensing events using an HST luminosity function convolved to
typical ground-based seeing, adopting a range of values for the stellar density
and seeing. We find that a significant fraction of bright events are blended,
contrary to the oft-quoted assumption that bright events should be free from
blending. We probe the effect that this erroneous assumption has on both the
observed event timescale distribution and the optical depth, using realistic
detection criteria relevent to the different surveys. Importantly, under this
assumption the latter quantity appears to be reasonably unaffected across our
adopted values for seeing and density. The timescale distribution is however
biased towards smaller values, even for the least dense fields. The dominant
source of blending is from lensing of faint source stars, rather than lensing
of bright source stars blended with nearby fainter stars. We also explore other
issues, such as the centroid motion of blended events and the phenomena of
`negative' blending. Furthermore, we breifly note that blending can affect the
determination of the centre of the red clump giant region from an observed
luminosity function. This has implications for a variety of studies, e.g.
mapping extinction towards the bulge and attempts to constrain the parameters
of the Galactic bar through red clump giant number counts. (Abridged)
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 19:26:08 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Smith",
"Martin C.",
""
],
[
"Wozniak",
"Przemyslaw",
""
],
[
"Mao",
"Shude",
""
],
[
"Sumi",
"Takahiro",
""
]
] |
0707.0551 | Ofer Yuli | Ofer Yuli, Itay Asulin, Gad Koren and Oded Millo | Scanning tunneling spectroscopy characterization of the pseudogap and
the x = 1/8 anomaly in La2-xSrxCuO4 thin films | 15 pages, 6 figures | Physical Review B 75, 184521 (2007) | 10.1103/PhysRevB.75.184521 | null | cond-mat.supr-con cond-mat.str-el | null | Using scanning tunneling spectroscopy we examined the local density of states
of thin c-axis La2-xSrxCuO4 films, over wide doping and temperature ranges. We
found that the pseudogap exists only at doping levels lower than optimal. For x
= 0.12, close to the 'anomalous' x = 1/8 doping level, a zero bias conductance
peak was the dominant spectral feature, instead of the excepted V- shaped
(c-axis tunneling) gap structure. We have established that this surprising
effect cannot be explained by tunneling into (110) facets. Possible origins for
this unique behavior are discussed.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 07:34:25 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Yuli",
"Ofer",
""
],
[
"Asulin",
"Itay",
""
],
[
"Koren",
"Gad",
""
],
[
"Millo",
"Oded",
""
]
] |
0707.0552 | Brihaye Yves | Y. Brihaye, E. Radu and D. H. Tchrakian | AdS$_5$ rotating non-Abelian black holes | 14 pages, 7 figures | Phys.Rev.D76:105005,2007 | 10.1103/PhysRevD.76.105005 | null | hep-th | null | We present arguments for the existence of charged, rotating black holes with
equal magnitude angular momenta in $d=5$ Einstein-Yang-Mills theory with
negative cosmological constant. These solutions posses a regular horizon of
spherical topology and approach asymptotically the Anti-de Sitter spacetime
background. The black hole solutions have also an electric charge and a
nonvanishing magnetic flux through the sphere at infinity. Different from the
static case, no regular solution with a nonvanishing angular momenta is found
for a vanishing event horizon radius.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 07:17:51 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Brihaye",
"Y.",
""
],
[
"Radu",
"E.",
""
],
[
"Tchrakian",
"D. H.",
""
]
] |
0707.0553 | S. M. Gerasyuta | S. M. Gerasyuta, V. I. Kochkin | Relativistic five-quark equations and a narrow N(1688) resonance | 9 pages, pdf | null | null | null | hep-ph | null | The relativistic five-quark equations are found in the framework of the
dispersion relation technique. The five-quark amplitude for the N(1688)
resonance including u-, d- quarks is calculated. The pole of this amplitude
determines the mass of non-strange pentaquark M=1686 MeV and the width about
7MeV. The results are in good agreement with the evidence for a narrow N(1688)
resonance.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 07:26:31 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Gerasyuta",
"S. M.",
""
],
[
"Kochkin",
"V. I.",
""
]
] |
0707.0554 | John Fredsted Mr. | John Fredsted | Natural octonionic generalization of general relativity | null | null | null | null | math-ph math.MP | null | An intriguingly natural generalization, using complex octonions, of general
relativity is pointed out. The starting point is the vierbein-based double dual
formulation of the Einstein-Hilbert action. In terms of two natural structures
on the (complex) quaternions and (complex) octonions, the inner product and the
cross products, respectively, this action is linked with the complex
quaternionic structure constants, and subsequently generalized to an
achtbein-based 'double chi-dual' action in terms of the complex octonionic
structure constants.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 07:39:09 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Fredsted",
"John",
""
]
] |
0707.0555 | W.D. van Suijlekom | Walter D. van Suijlekom | Multiplicative renormalization and Hopf algebras | 13 pages; uses feynmp | null | null | null | hep-th | null | We derive the existence of Hopf subalgebras generated by Green's functions in
the Hopf algebra of Feynman graphs of a quantum field theory. This means that
the coproduct closes on these Green's functions. It allows us for example to
derive Dyson's formulas in quantum electrodynamics relating the renormalized
and bare proper functions via the renormalization constants and the analogous
formulas for non-abelian gauge theories. In the latter case, we observe the
crucial role played by Slavnov--Taylor identities.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 08:23:42 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"van Suijlekom",
"Walter D.",
""
]
] |
0707.0556 | Roberto Amadio | Roberto Amadio (PPS), Mehdi Dogguy (PPS) | Determinacy in a synchronous pi-calculus | To appear in the book `From semantics to computer science: essays in
honor of Gilles Kahn', Cambridge University Press | From semantics to computer science: essays in honor of Gilles
Kahn, Y. Bertot et al. (Ed.) (2009) 1-27 | null | null | cs.LO | null | The S-pi-calculus is a synchronous pi-calculus which is based on the SL
model. The latter is a relaxation of the Esterel model where the reaction to
the absence of a signal within an instant can only happen at the next instant.
In the present work, we present and characterise a compositional semantics of
the S-pi-calculus based on suitable notions of labelled transition system and
bisimulation. Based on this semantic framework, we explore the notion of
determinacy and the related one of (local) confluence.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 08:12:17 GMT"
},
{
"version": "v2",
"created": "Mon, 11 Feb 2008 18:58:19 GMT"
}
] | 2010-07-01T00:00:00 | [
[
"Amadio",
"Roberto",
"",
"PPS"
],
[
"Dogguy",
"Mehdi",
"",
"PPS"
]
] |
0707.0557 | Charles M. Marcus | E. A. Laird, C. Barthel, E. I. Rashba, C. M. Marcus, M. P. Hanson, A.
C. Gossard | Hyperfine-mediated gate-driven electron spin resonance | related papers available at http://marcuslab.harvard.edu | Phys. Rev. Lett. 99 246601 (2007) | 10.1103/PhysRevLett.99.246601 | null | cond-mat.mes-hall | null | An all-electrical spin resonance effect in a GaAs few-electron double quantum
dot is investigated experimentally and theoretically. The magnetic field
dependence and absence of associated Rabi oscillations are consistent with a
novel hyperfine mechanism. The resonant frequency is sensitive to the
instantaneous hyperfine effective field, and the effect can be used to detect
and create sizable nuclear polarizations. A device incorporating a micromagnet
exhibits a magnetic field difference between dots, allowing electrons in either
dot to be addressed selectively.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 08:19:53 GMT"
},
{
"version": "v2",
"created": "Wed, 19 Dec 2007 13:08:11 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Laird",
"E. A.",
""
],
[
"Barthel",
"C.",
""
],
[
"Rashba",
"E. I.",
""
],
[
"Marcus",
"C. M.",
""
],
[
"Hanson",
"M. P.",
""
],
[
"Gossard",
"A. C.",
""
]
] |
0707.0558 | Yoshiharu Asaki | Yoshiharu Asaki, Hiroshi Sudou, Yusuke Kono, Akihiro Doi, Richard
Dodson, Nicolas Pradel, Yasuhiro Murata, Nanako Mochizuki, Philip G. Edwards,
Tetsuo Sasao, Edward B. Fomalont | Verification of the Effectiveness of VSOP-2 Phase Referencing with a
Newly Developed Simulation Tool, ARIS | about 30 pages, 18 figures | Publ.Astron.Soc.Jap.59:397,2007 | 10.1093/pasj/59.2.397 | null | astro-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The next-generation space VLBI mission, VSOP-2, is expected to provide
unprecedented spatial resolutions at 8.4, 22, and 43GHz. In this report, phase
referencing with VSOP-2 is examined in detail based on a simulation tool called
ARIS. The criterion for successful phase referencing was to keep the phase
errors below one radian. Simulations with ARIS reveal that phase referencing
achieves good performance at 8.4GHz, even under poor tropospheric conditions.
At 22 and 43GHz, it is recommended to conduct phase referencing observations
under good or typical tropospheric conditions. The satellite is required to
have an attitude-switching capability with a one-minute or shorter cycle, and
an orbit determination accuracy higher than about 10cm at apogee; the phase
referencing calibrators are required to have a signal-to-noise ratio larger
than four for a single scan. The probability to find a suitable phase
referencing calibrator was estimated by using VLBI surveys. From the viewpoint
of calibrator availability, VSOP-2 phase referencing at 8.4GHz is promising.
However, the change of finding suitable calibrators at 22 and 43GHz is
significantly reduced; it is important to conduct specific investigations for
each target at those frequencies.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 08:58:15 GMT"
},
{
"version": "v2",
"created": "Wed, 28 Jul 2010 03:18:06 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Asaki",
"Yoshiharu",
""
],
[
"Sudou",
"Hiroshi",
""
],
[
"Kono",
"Yusuke",
""
],
[
"Doi",
"Akihiro",
""
],
[
"Dodson",
"Richard",
""
],
[
"Pradel",
"Nicolas",
""
],
[
"Murata",
"Yasuhiro",
""
],
[
"Mochizuki",
"Nanako",
""
],
[
"Edwards",
"Philip G.",
""
],
[
"Sasao",
"Tetsuo",
""
],
[
"Fomalont",
"Edward B.",
""
]
] |
0707.0559 | Shiyong Liu | S. Y. Liu, X. L. Lei and Norman J. M. Horing | Diffusive transport in graphene: the role of interband correlation | 7 pages, 1 figure; discussion concerning the effects of interband
correlation added | null | 10.1063/1.2969787 | null | cond-mat.mtrl-sci | null | We present a kinetic equation approach to investigate dc transport properties
of graphene in the diffusive regime considering long-range electron-impurity
scattering. In our study, the effects of interband correlation (or
polarization) on conductivity are taken into account. We find that the
conductivity contains not only the usual term inversely proportional to
impurity density $N_i$, but also an anomalous term that is linear in $N_i$.
This leads to a minimum in the density dependence of conductivity when the
electron density $N_{\rm e}$ is equal to a critical value, $N_c$. For $N_{\rm
e}>N_c$ the conductivity varies almost linearly with the electron density,
while it is approximately inversely proportional to $N_{\rm e}$ when $N_{\rm
e}<N_c$ in the diffusive regime. The effects of various scattering potentials
on the conductivity minimum are also analyzed. Using typical experimental
parameters, we find that for RPA screened electron-impurity scattering the
minimum conductivity is about $5.1 e^2/h$ when $N_{\rm e}\approx 0.32N_i$.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:02:41 GMT"
},
{
"version": "v2",
"created": "Sun, 15 Jul 2007 02:56:20 GMT"
},
{
"version": "v3",
"created": "Wed, 5 Dec 2007 04:11:57 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Liu",
"S. Y.",
""
],
[
"Lei",
"X. L.",
""
],
[
"Horing",
"Norman J. M.",
""
]
] |
0707.0560 | Jae Dong Noh | Jae Dong Noh (UOS) | Percolation and Loop Statistics in Complex Networks | 4 pages and 2 figures; A major revision has been made | Eur. Phys. J. B 66, 251 (2008) | 10.1140/epjb/e2008-00401-9 | null | cond-mat.stat-mech | null | Complex networks display various types of percolation transitions. We show
that the degree distribution and the degree-degree correlation alone are not
sufficient to describe diverse percolation critical phenomena. This suggests
that a genuine structural correlation is an essential ingredient in
characterizing networks. As a signature of the correlation we investigate a
scaling behavior in $M_N(h)$, the number of finite loops of size $h$, with
respect to a network size $N$. We find that networks, whose degree
distributions are not too broad, fall into two classes exhibiting $M_N(h)\sim
({constant})$ and $M_N(h) \sim (\ln N)^\psi$, respectively. This classification
coincides with the one according to the percolation critical phenomena.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:03:15 GMT"
},
{
"version": "v2",
"created": "Tue, 14 Aug 2007 06:35:33 GMT"
}
] | 2008-11-27T00:00:00 | [
[
"Noh",
"Jae Dong",
"",
"UOS"
]
] |
0707.0561 | Pascale Jablonka | P. Jablonka, J. Gorgas, and P. Goudfrooij | Stellar Population Gradients in Bulges along the Hubble Sequence: II.
Relations with Galaxy Properties | Accepted for publication in A&A | null | 10.1051/0004-6361:20066691 | null | astro-ph | null | We present the analysis of the radial gradients of stellar absorption lines
in a sample of 32 bulges of edge-on spiral galaxies, spanning nearly the full
Hubble sequence (from S0 to Sc types), and a large range of velocity dispersion
(from about 60 to 300 km/s). Different diagnostics such as index-index,
gradient-gradient diagrams, and simple stellar population models are used to
tackle the origin of the variation of the bulge stellar population. We find
that the vast majority of bulges show older age, lower metallicity and higher
[alpha/Fe] in their outer regions than in their central parts. The radial
gradients in [Fe/H] are 2 to 3 times larger than in Log(age). The relation
between gradient and bulge velocity dispersion is interpreted as a gradual
build up of the gradient mean values and their dispersions from high to low
velocity dispersion, rather than a pure correlation. The bulge effective radii
and the Hubble type of the parent galaxies seem to play a more minor role in
causing the observed spatial distributions. At a given velocity dispersion,
bulges and ellipticals share common properties.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:15:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Jablonka",
"P.",
""
],
[
"Gorgas",
"J.",
""
],
[
"Goudfrooij",
"P.",
""
]
] |
0707.0562 | Stefan G\"oller | Stefan G\"oller and Dirk Nowotka | On a Non-Context-Free Extension of PDL | null | null | null | null | cs.LO | null | Over the last 25 years, a lot of work has been done on seeking for decidable
non-regular extensions of Propositional Dynamic Logic (PDL). Only recently, an
expressive extension of PDL, allowing visibly pushdown automata (VPAs) as a
formalism to describe programs, was introduced and proven to have a
satisfiability problem complete for deterministic double exponential time.
Lately, the VPA formalism was extended to so called k-phase multi-stack visibly
pushdown automata (k-MVPAs). Similarly to VPAs, it has been shown that the
language of k-MVPAs have desirable effective closure properties and that the
emptiness problem is decidable. On the occasion of introducing k-MVPAs, it has
been asked whether the extension of PDL with k-MVPAs still leads to a decidable
logic. This question is answered negatively here. We prove that already for the
extension of PDL with 2-phase MVPAs with two stacks satisfiability becomes
\Sigma_1^1-complete.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:33:21 GMT"
},
{
"version": "v2",
"created": "Wed, 18 Jul 2007 10:11:01 GMT"
}
] | 2007-07-18T00:00:00 | [
[
"Göller",
"Stefan",
""
],
[
"Nowotka",
"Dirk",
""
]
] |
0707.0563 | Markus Janousch | M. Janousch, G. I. Meijer, U. Staub, B. Delley, S. F. Karg, B. P.
Andreasson | Role of oxygen vacancies in Cr-doped SrTiO3 for resistance-change memory | 13 pages, 3 figures | null | null | null | cond-mat.mtrl-sci cond-mat.str-el | null | Transition-metal oxides exhibiting a bistable resistance state are attractive
for non-volatile memory applications. The relevance of oxygen vacancies (VO)
for the resistance-change memory was investigated with x-ray fluorescence,
infrared microscopy, and x-ray absorption spectroscopy using Cr-doped SrTiO3 as
example. We propose that the microscopic origin of resistance switching in this
class of materials is due to an oxygen-vacancy drift occurring in close
proximity to one of the electrodes.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:26:57 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Janousch",
"M.",
""
],
[
"Meijer",
"G. I.",
""
],
[
"Staub",
"U.",
""
],
[
"Delley",
"B.",
""
],
[
"Karg",
"S. F.",
""
],
[
"Andreasson",
"B. P.",
""
]
] |
0707.0564 | Nicolas Borghini | Nicolas Borghini, Urs Achim Wiedemann | Predictions for the LHC heavy ion programme | 37 pages, 6 figures; invited topical review for Journal of Physics G | J.Phys.G35:023001,2008 | 10.1088/0954-3899/35/2/023001 | BI-TP 2007/10, CERN-PH-TH/2007-102 | hep-ph nucl-ex nucl-th | null | Apparently universal trends have been observed in relativistic
nucleus-nucleus collisions up to RHIC energies. Here, we review these trends
and we discuss their agnostic extrapolation to heavy ion collisions at the LHC.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:50:37 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Borghini",
"Nicolas",
""
],
[
"Wiedemann",
"Urs Achim",
""
]
] |
0707.0565 | Emilio Kropff | Emilio Kropff and Alessandro Treves | Uninformative memories will prevail: the storage of correlated
representations and its consequences | 24 pages, 3 Figures. Submitted to HFSP Journal. New version has .EPS
figures. Now accepted in the HFSP Journal. New version includes deep
structural changes following reviewers suggestions | null | null | null | cond-mat.dis-nn cond-mat.other | null | Autoassociative networks were proposed in the 80's as simplified models of
memory function in the brain, using recurrent connectivity with hebbian
plasticity to store patterns of neural activity that can be later recalled.
This type of computation has been suggested to take place in the CA3 region of
the hippocampus and at several levels in the cortex. One of the weaknesses of
these models is their apparent inability to store correlated patterns of
activity. We show, however, that a small and biologically plausible
modification in the `learning rule' (associating to each neuron a plasticity
threshold that reflects its popularity) enables the network to handle
correlations. We study the stability properties of the resulting memories (in
terms of their resistance to the damage of neurons or synapses), finding a
novel property of autoassociative networks: not all memories are equally
robust, and the most informative are also the most sensitive to damage. We
relate these results to category-specific effects in semantic memory patients,
where concepts related to `non-living things' are usually more resistant to
brain damage than those related to `living things', a phenomenon suspected to
be rooted in the correlation between representations of concepts in the cortex.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:29:57 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 10:56:51 GMT"
},
{
"version": "v3",
"created": "Fri, 21 Sep 2007 13:35:45 GMT"
}
] | 2011-11-10T00:00:00 | [
[
"Kropff",
"Emilio",
""
],
[
"Treves",
"Alessandro",
""
]
] |
0707.0566 | Christophe Adami | C. Adami, J. P. Picat, F. Durret, A. Mazure, R. Pello, M. West | Coma cluster object populations down to M_R~-9.5 | To be published in A&A | null | 10.1051/0004-6361:20077446 | null | astro-ph | null | This study follows a recent analysis of the galaxy luminosity functions and
colour-magnitude red sequences in the Coma cluster (Adami et al. 2007). We
analyze here the distribution of very faint galaxies and globular clusters in
an east-west strip of $\sim 42 \times 7$ arcmin$^2$ crossing the Coma cluster
center (hereafter the CS strip) down to the unprecedented faint absolute
magnitude of M$_R \sim -9.5$. This work is based on deep images obtained at the
CFHT with the CFH12K camera in the B, R, and I bands. The analysis shows that
the observed properties strongly depend on the environment, and thus on the
cluster history. When the CS is divided into four regions, the westernmost
region appears poorly populated, while the regions around the brightest
galaxies NGC 4874 and NGC 4889 (NGC 4874 and NGC 4889 being masked) are
dominated by faint blue galaxies. They show a faint luminosity function slope
of -2, very significantly different from the field estimates. Results are
discussed in the framework of galaxy destruction (which can explain part of the
very faint galaxy population) and of structures infalling on to Coma.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:01:07 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Adami",
"C.",
""
],
[
"Picat",
"J. P.",
""
],
[
"Durret",
"F.",
""
],
[
"Mazure",
"A.",
""
],
[
"Pello",
"R.",
""
],
[
"West",
"M.",
""
]
] |
0707.0567 | Nicolas Pollet | Ana C Fierro (DE), Rapha\"el Thuret (DE), Laurent Coen (ERE, LPGC),
Muriel Perron (DE), Barbara A Demeneix (ERE, LPGC), Maurice Wegnez (DE),
Gabor Gyapay (SEG), Jean Weissenbach (SEG), Patrick Wincker (SEG), Andr\'e
Mazabraud (DE), Nicolas Pollet (DE) | Exploring nervous system transcriptomes during embryogenesis and
metamorphosis in Xenopus tropicalis using EST analysis | null | BMC Genomics 8 (2007) 118 | 10.1186/1471-2164-8-118 | null | q-bio.GN q-bio.QM | null | Xenopus tropicalis is an anuran amphibian species used as model in vertebrate
comparative genomics. It provides the same advantages as Xenopus laevis but is
diploid and has a smaller genome of 1.7 Gbp. Therefore X. tropicalis is more
amenable to systematic transcriptome surveys. We initiated a large-scale
partial cDNA sequencing project to provide a functional genomics resource on
genes expressed in the nervous system during early embryogenesis and
metamorphosis in X. tropicalis. A gene index was defined and analysed after the
collection of over 48,785 high quality sequences. Partial cDNA sequences were
obtained from an embryonic head and retina library (30,272 sequences) and from
a metamorphic brain and spinal cord library (27,602 sequences). These ESTs are
estimated to represent 9,693 transcripts derived from an estimated 6,000 genes.
An estimated 46% of these cDNA sequences contain their start codon. Further
annotation included Gene Ontology functional classification, InterPro domain
analysis, alternative splicing and non-coding RNA identification. Gene
expression profiles were derived from EST counts and used to define transcripts
specific to metamorphic stages of development. Moreover, these ESTs allowed
identification of a set of 225 polymorphic microsatellites that can be used as
genetic markers. These cDNA sequences permit in silico cloning of numerous
genes and will facilitate studies aimed at deciphering the roles of cognate
genes expressed in the nervous system during neural development and
metamorphosis. The genomic resources developed to study X. tropicalis biology
will accelerate exploration of amphibian physiology and genetics.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:02:36 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Fierro",
"Ana C",
"",
"DE"
],
[
"Thuret",
"Raphaël",
"",
"DE"
],
[
"Coen",
"Laurent",
"",
"ERE, LPGC"
],
[
"Perron",
"Muriel",
"",
"DE"
],
[
"Demeneix",
"Barbara A",
"",
"ERE, LPGC"
],
[
"Wegnez",
"Maurice",
"",
"DE"
],
[
"Gyapay",
"Gabor",
"",
"SEG"
],
[
"Weissenbach",
"Jean",
"",
"SEG"
],
[
"Wincker",
"Patrick",
"",
"SEG"
],
[
"Mazabraud",
"André",
"",
"DE"
],
[
"Pollet",
"Nicolas",
"",
"DE"
]
] |
0707.0568 | Gesualdo Scutari | Gesualdo Scutari, D.P. Palomar, S. Barbarossa | Optimal Linear Precoding Strategies for Wideband Non-Cooperative Systems
based on Game Theory-Part I: Nash Equilibria | Paper submitted to IEEE Transactions on Signal Processing, September
22, 2005. Revised March 14, 2007. Accepted June 5, 2007. To be published on
IEEE Transactions on Signal Processing, 2007. To appear on IEEE Transactions
on Signal Processing, 2007 | null | 10.1109/TSP.2007.907807 | null | cs.IT cs.GT math.IT | null | In this two-parts paper we propose a decentralized strategy, based on a
game-theoretic formulation, to find out the optimal precoding/multiplexing
matrices for a multipoint-to-multipoint communication system composed of a set
of wideband links sharing the same physical resources, i.e., time and
bandwidth. We assume, as optimality criterion, the achievement of a Nash
equilibrium and consider two alternative optimization problems: 1) the
competitive maximization of mutual information on each link, given constraints
on the transmit power and on the spectral mask imposed by the radio spectrum
regulatory bodies; and 2) the competitive maximization of the transmission
rate, using finite order constellations, under the same constraints as above,
plus a constraint on the average error probability. In Part I of the paper, we
start by showing that the solution set of both noncooperative games is always
nonempty and contains only pure strategies. Then, we prove that the optimal
precoding/multiplexing scheme for both games leads to a channel diagonalizing
structure, so that both matrix-valued problems can be recast in a simpler
unified vector power control game, with no performance penalty. Thus, we study
this simpler game and derive sufficient conditions ensuring the uniqueness of
the Nash equilibrium. Interestingly, although derived under stronger
constraints, incorporating for example spectral mask constraints, our
uniqueness conditions have broader validity than previously known conditions.
Finally, we assess the goodness of the proposed decentralized strategy by
comparing its performance with the performance of a Pareto-optimal centralized
scheme. To reach the Nash equilibria of the game, in Part II, we propose
alternative distributed algorithms, along with their convergence conditions.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:33:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Scutari",
"Gesualdo",
""
],
[
"Palomar",
"D. P.",
""
],
[
"Barbarossa",
"S.",
""
]
] |
0707.0569 | Roberto Monaco | R. Monaco, M. Aaroe, J. Mygind, R.J. Rivers and V.P. Koshelets | Spontaneous Fluxon Production in Annular Josephson Tunnel Junctions in
the Presence of a Magnetic Field | Submitted to Phys. Rev. B with 5 figures on Nov. 15, 2007 | Phys. Rev. B 77, 054509, 2008 | 10.1103/PhysRevB.77.054509 | null | cond-mat.supr-con | null | We report on the spontaneous production of fluxons in the presence of a
symmetry-breaking magnetic field for annular Josephson tunnel junctions during
a thermal quench. The dependence on field intensity $B$ of the probability
$\bar{f_1}$ to trap a single defect during the N-S phase transition drastically
depends on the sample circumferences. We show that the data can be understood
in the framework of the Kibble-Zurek picture of spontaneous defect formation
controlled by causal bounds.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:37:30 GMT"
},
{
"version": "v2",
"created": "Thu, 15 Nov 2007 15:46:50 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Monaco",
"R.",
""
],
[
"Aaroe",
"M.",
""
],
[
"Mygind",
"J.",
""
],
[
"Rivers",
"R. J.",
""
],
[
"Koshelets",
"V. P.",
""
]
] |
0707.0570 | Yurii A. Neretin | Yuri Neretin | Gauss--Berezin integral operators and spinors over supergroups
$\mathrm{OSp}(2p|2q)$, and Lagrangian super-Grasmannians | 60pp, extended version, typos are corrected | null | null | ESI-1968 | math.RT math-ph math.MP | http://creativecommons.org/licenses/by/4.0/ | We obtain explicit formulas for the spinor representation $\rho$ of the real
orthosymplectic supergroup $\mathrm{OSp}(2p|2q,\mathbb{R})$ by integral
'Gauss--Berezin' operators. Next, we extend $\rho$ to a complex domain and get
a representation of a larger semigroup, which is a counterpart of Olshanski
subsemigroups in semisimple Lie groups. Further, we show that $\rho$ can be
extended to an operator-valued function on a certain domain in the Lagrangian
super-Grassmannian (graphs of elements of the supergroup
$\mathrm{OSp}(2p|2q,\mathbb{C})$ are Lagrangian super-subspaces) and show that
this function is a 'representation' in the following sense: we consider
Lagrangian subspaces as linear relations and composition of two Lagrangian
relations in general position corresponds to a product of Gauss--Berezin
operators
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:41:32 GMT"
},
{
"version": "v2",
"created": "Tue, 8 Apr 2008 19:42:43 GMT"
},
{
"version": "v3",
"created": "Fri, 12 Jun 2009 12:23:26 GMT"
},
{
"version": "v4",
"created": "Fri, 6 Oct 2023 19:58:39 GMT"
}
] | 2023-10-10T00:00:00 | [
[
"Neretin",
"Yuri",
""
]
] |
0707.0571 | Alexander Olshanskiy | A.Yu.Olshanskii | Linear automorphism groups of relatively free groups | 4 pages | null | null | null | math.GR math.RT | null | Let G be a free group in a variety of groups, but G is not absolutely free.
We prove that the group of automorphisms Aut(G) is linear iff G is a virtually
nilpotent group.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:42:07 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Olshanskii",
"A. Yu.",
""
]
] |
0707.0572 | Mauro Sereno | M. Sereno (Univ. Zurich) | On the deprojection of clusters of galaxies combining X-ray,
Sunyaev-Zeldovich temperature decrement and gravitational lensing maps | 13 pages, 8 figures; accepted for publication in MNRAS | null | 10.1111/j.1365-2966.2007.12171.x | null | astro-ph | null | Knowledge of the intrinsic shape of galaxy clusters is very important in
investigating cosmic structure formation and astrophysical processes. The
reconstruction of the 3-dimensional structure usually relies on deprojecting
2-dimensional X-ray, Sunyaev-Zeldovich (SZ) and/or gravitational lensing
observations. As known, a joint analysis of these data sets can provide the
elongation of the cluster along the line of sight together with its length and
width in the plane of the sky. An unbiased measurement of the Hubble constant
can be also inferred. Due to some intrinsic degeneracies, the observational
constraints obtained from such projected data-sets are not enough to allow an
unique inversion. In general, the projected maps can be at the same time
compatible with prolate, oblate and with many triaxial configurations. Even a
prolate cluster might be interpreted as an oblate system and vice versa.
Assuming that the cluster is axially symmetric is likely to overestimate the
intrinsic ellipticity, whereas the system always looks rounder performing the
inversion under the hypothesis of a triaxial cluster aligned with the line of
sight. In general, analysing triaxial clusters under the prolate or oblate
assumption may introduce strong biases even when the clusters are actually near
to axial symmetry whereas the systematics introduced assuming the cluster to be
aligned with the line of sight are more under control.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:46:46 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sereno",
"M.",
"",
"Univ. Zurich"
]
] |
0707.0573 | Valentina Bianchin | G. Di Cocco, V. Bianchin, L. Foschini, F. Gianotti, P. Laurent, G.
Malaguti, L. Natalucci, F. Schiavone | Ibis/Picsit Status | 4 pages, 5 figures. Proceedings of the 6th INTEGRAL Workshop, to be
published in ESA SP-622 | null | null | null | astro-ph | null | We report about the status of the PICsIT layer of the imager IBIS. The
instrument has been tested in both Spectral Imaging and Spectral Timing Mode.
PICsIT Single Events, Multiple and ISGRI data of the Crab are simultaneously
fitted to a power law model and fit parameters are compared with the standard
values. We present a joint fit of SPI, ISGRI, PICsIT data of the long
GRB041219, that was seen by the PICsIT instrument in both Spectral Imaging and
Spectral Timing acquisition modes. This allowed us to generate a preliminary
version of the instrumental response matrices for the PICsIT Spectral Timing
mode.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:46:58 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Di Cocco",
"G.",
""
],
[
"Bianchin",
"V.",
""
],
[
"Foschini",
"L.",
""
],
[
"Gianotti",
"F.",
""
],
[
"Laurent",
"P.",
""
],
[
"Malaguti",
"G.",
""
],
[
"Natalucci",
"L.",
""
],
[
"Schiavone",
"F.",
""
]
] |
0707.0574 | Alberto Bernacchia | Alberto Bernacchia, Philippe Naveau | Detecting spatial patterns with the cumulant function. Part I: The
theory | 9 pages, 3 figures | null | 10.5194/npg-15-159-2008 | null | math.ST stat.TH | null | In climate studies, detecting spatial patterns that largely deviate from the
sample mean still remains a statistical challenge. Although a Principal
Component Analysis (PCA), or equivalently a Empirical Orthogonal Functions
(EOF) decomposition, is often applied on this purpose, it can only provide
meaningful results if the underlying multivariate distribution is Gaussian.
Indeed, PCA is based on optimizing second order moments quantities and the
covariance matrix can only capture the full dependence structure for
multivariate Gaussian vectors. Whenever the application at hand can not satisfy
this normality hypothesis (e.g. precipitation data), alternatives and/or
improvements to PCA have to be developed and studied. To go beyond this second
order statistics constraint that limits the applicability of the PCA, we take
advantage of the cumulant function that can produce higher order moments
information. This cumulant function, well-known in the statistical literature,
allows us to propose a new, simple and fast procedure to identify spatial
patterns for non-Gaussian data. Our algorithm consists in maximizing the
cumulant function. To illustrate our approach, its implementation for which
explicit computations are obtained is performed on three family of of
multivariate random vectors. In addition, we show that our algorithm
corresponds to selecting the directions along which projected data display the
largest spread over the marginal probability density tails.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 11:03:17 GMT"
}
] | 2020-01-29T00:00:00 | [
[
"Bernacchia",
"Alberto",
""
],
[
"Naveau",
"Philippe",
""
]
] |
0707.0575 | Vladimir S. Gerdjikov | N. A. Kostov (Institute of Electronics, Bulgarian Academy of Sciences,
Sofia, Bulgaria), R. Dandoloff (Universit\'e de Cergy-Pontoise,
Cergy-Pontoise, France), V. S. Gerdjikov (Institute for Nuclear Research and
Nuclear Energy, Bulgarian Academy of Sciences, Sofia, Bulgaria), G. G.
Grahovski (Institute for Nuclear Research and Nuclear Energy, Bulgarian
Academy of Sciences, Sofia, Bulgaria) | The Manakov system as two moving interacting curves | In the Proceedings of the International Workshop "Complex structures
and vector fields", August 21--26, 2006, Sofia, Bulgaria. Eds.: K. Sekigawa,
S. Dimiev. World Scientific (2007) | null | null | null | nlin.SI | null | The two time-dependent Schrodinger equations in a potential V(s,u), $u$
denoting time, can be interpreted geometrically as a moving interacting curves
whose Fermi-Walker phase density is given by -dV/ds. The Manakov model appears
as two moving interacting curves using extended da Rios system and two Hasimoto
transformations.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 10:50:59 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Kostov",
"N. A.",
"",
"Institute of Electronics, Bulgarian Academy of Sciences,\n Sofia, Bulgaria"
],
[
"Dandoloff",
"R.",
"",
"Université de Cergy-Pontoise,\n Cergy-Pontoise, France"
],
[
"Gerdjikov",
"V. S.",
"",
"Institute for Nuclear Research and\n Nuclear Energy, Bulgarian Academy of Sciences, Sofia, Bulgaria"
],
[
"Grahovski",
"G. G.",
"",
"Institute for Nuclear Research and Nuclear Energy, Bulgarian\n Academy of Sciences, Sofia, Bulgaria"
]
] |
0707.0576 | Dmitri A. Uzdensky | Dmitri A. Uzdensky (Princeton University) and Andrew I. MacFadyen (IAS
and NYU) | Magnetically-dominated jets inside collapsing stars as a model for
gamma-ray bursts and supernova explosions | Invited paper in the "Physics of Plasmas" (May 2007 special issue),
based on an invited talk at the 48th Annual Meeting of the APS Division of
Plasma Physics (Oct. 30 - Nov. 3, 2006, Philadelphia, PA); 24 pages, 7
figures | Phys.Plasmas14:056506,2007 | 10.1063/1.2721969 | null | astro-ph physics.plasm-ph | null | It has been suggested that magnetic fields play a dynamically-important role
in core-collapse explosions of massive stars. In particular, they may be
important in the collapsar scenario for gamma-ray bursts (GRB), where the
central engine is a hyper-accreting black hole or a millisecond magnetar. The
present paper is focussed on the magnetar scenario, with a specific emphasis on
the interaction of the magnetar magnetosphere with the infalling stellar
envelope. First, the ``Pulsar-in-a-Cavity'' problem is introduced as a paradigm
for a magnetar inside a collapsing star. The basic set-up of this fundamental
plasma-physics problem is described, outlining its main features, and simple
estimates are derived for the evolution of the magnetic field. In the context
of a collapsing star, it is proposed that, at first, the ram pressure of the
infalling plasma acts to confine the magnetosphere, enabling a gradual build-up
of the magnetic pressure. At some point, the growing magnetic pressure
overtakes the (decreasing) ram pressure of the gas, resulting in a
magnetically-driven explosion. The explosion should be highly anisotropic, as
the hoop-stress of the toroidal field, confined by the surrounding stellar
matter, collimates the magnetically-dominated outflow into two beamed
magnetic-tower jets. This creates a clean narrow channel for the escape of
energy from the central engine through the star, as required for GRBs. In
addition, the delayed onset of the collimated-explosion phase can explain the
production of large quantities of Nickel-56, as suggested by the GRB-Supernova
connection. Finally, the prospects for numerical simulations of this scenario
are discussed.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 19:55:37 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Uzdensky",
"Dmitri A.",
"",
"Princeton University"
],
[
"MacFadyen",
"Andrew I.",
"",
"IAS\n and NYU"
]
] |
0707.0577 | Irina Sagert | I. Sagert, J. Schaffner-Bielich | Pulsar kicks by anisotropic neutrino emission from quark matter | 6 pages, 3 figures, poster contribution at the conference "Nuclear
Physics in Astrophysics III",Dresden,March 26-31,2007 | J.Phys.G35:014062,2008 | 10.1088/0954-3899/35/1/014062 | null | astro-ph | null | We discuss an acceleration mechanism for pulsars out of their supernova
remnants based on asymmetric neutrino emission from quark matter in the
presence of a strong magnetic field. The polarized electron spin fixes the
neutrino emission from the direct quark Urca process in one direction along the
magnetic field. We calculate the magnetic field strength which is required to
polarize the electron spin as well as the required initial proto-neutron star
temperature for a successfull acceleration mechanism. In addition we discuss
the neutrino mean free paths in quark as well as in neutron matter which turn
out to be very small. Consequently, the high neutrino interaction rates will
wash out the asymmetry in neutrino emission. As a possible solution to this
problem we take into account effects from colour superconductivity.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 11:15:37 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Sagert",
"I.",
""
],
[
"Schaffner-Bielich",
"J.",
""
]
] |
0707.0578 | Manoranjan P. Singh | S. Raj Mohan, M. P. Joshi, and Manoranjan P. Singh | Charge transport in disordered organic solids: A Monte Carlo simulation
study on the effects of film morphology | 27 pages, 7 figures | null | null | null | cond-mat.dis-nn cond-mat.mtrl-sci | null | The influence of ordered regions (micro crystallites and aggregates) in the
other wise disordered polymer host matrix on field and temperature dependence
of mobility (\mu) has been simulated. Increase in concentration of ordered
regions leads to increase in magnitude of mobility and in high field regime the
saturation of the mobility occurs at lower electric field strength. The
influence of different mean and standard deviation of Gaussian density of
states (DOS) of ordered regions on the field dependence of mobility was studied
and found to be significant only at higher concentrations. Weak influence of
these parameters at low concentrations are attributed to the strong interface
effects due to the difference in the standard deviation of DOS of two regions
(host and ordered region) and shallow trapping effect by ordered regions. For
all the parameters of ordered regions under investigation the temperature
dependence of mobility (log{\mu}) and the slope of log{\mu} Vs E^{1/2} plot
show 1/T^2 dependence.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 11:25:21 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Mohan",
"S. Raj",
""
],
[
"Joshi",
"M. P.",
""
],
[
"Singh",
"Manoranjan P.",
""
]
] |
0707.0579 | Vincenzo Galdi | Vincenzo Pierro, Vincenzo Galdi, Giuseppe Castaldi, Innocenzo M.
Pinto, Juri Agresti, and Riccardo DeSalvo | Perspectives on Beam-Shaping Optimization for Thermal-Noise Reduction in
Advanced Gravitational-Wave Interferometric Detectors: Bounds, Profiles, and
Critical Parameters | 12 pages, 9 figures, 2 tables | Phys.Rev.D76:122003,2007 | 10.1103/PhysRevD.76.122003 | LIGO-P070066-01-Z | gr-qc | null | Suitable shaping (in particular, flattening and broadening) of the laser beam
has recently been proposed as an effective device to reduce internal (mirror)
thermal noise in advanced gravitational wave interferometric detectors. Based
on some recently published analytic approximations (valid in the
infinite-test-mass limit) for the Brownian and thermoelastic mirror noises in
the presence of arbitrary-shaped beams, this paper addresses certain
preliminary issues related to the optimal beam-shaping problem. In particular,
with specific reference to the Laser Interferometer Gravitational-wave
Observatory (LIGO) experiment, absolute and realistic lower-bounds for the
various thermal noise constituents are obtained and compared with the current
status (Gaussian beams) and trends ("mesa" beams), indicating fairly ample
margins for further reduction. In this framework, the effective dimension of
the related optimization problem, and its relationship to the critical design
parameters are identified, physical-feasibility and model-consistency issues
are considered, and possible additional requirements and/or prior information
exploitable to drive the subsequent optimization process are highlighted.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 15:31:10 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Pierro",
"Vincenzo",
""
],
[
"Galdi",
"Vincenzo",
""
],
[
"Castaldi",
"Giuseppe",
""
],
[
"Pinto",
"Innocenzo M.",
""
],
[
"Agresti",
"Juri",
""
],
[
"DeSalvo",
"Riccardo",
""
]
] |
0707.0580 | Felix Ritort | J.-D. Wen, M. Manosas, P. T. X. Li, S. B. Smith, C. Bustamante, F.
Ritort, I. Tinoco Jr | Force unfolding kinetics of RNA using optical tweezers. I. Effects of
experimental variables on measured results | PDF file, 30 pages, 7 figures | Biophysical Journal, 92 (2007) 2996-3009 | 10.1529/biophysj.106.094052 | null | physics.bio-ph cond-mat.soft cond-mat.stat-mech q-bio.BM | null | Experimental variables of optical tweezers instrumentation that affect RNA
folding/unfolding kinetics were investigated. A model RNA hairpin, P5ab, was
attached to two micron-sized beads through hybrid RNA/DNA handles; one bead was
trapped by dual-beam lasers and the other was held by a micropipette. Several
experimental variables were changed while measuring the unfolding/refolding
kinetics, including handle lengths, trap stiffness, and modes of force applied
to the molecule. In constant-force mode where the tension applied to the RNA
was maintained through feedback control, the measured rate coefficients varied
within 40% when the handle lengths were changed by 10 fold (1.1 to 10.2 Kbp);
they increased by two- to three-fold when the trap stiffness was lowered to one
third (from 0.1 to 0.035 pN/nm). In the passive mode, without feedback control
and where the force applied to the RNA varied in response to the end-to-end
distance change of the tether, the RNA hopped between a high-force folded-state
and a low-force unfolded-state. In this mode, the rates increased up to
two-fold with longer handles or softer traps. Overall, the measured rates
remained with the same order-of-magnitude over the wide range of conditions
studied. In the companion paper (1), we analyze how the measured kinetics
parameters differ from the intrinsic molecular rates of the RNA, and thus how
to obtain the molecular rates.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 11:28:47 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wen",
"J. -D.",
""
],
[
"Manosas",
"M.",
""
],
[
"Li",
"P. T. X.",
""
],
[
"Smith",
"S. B.",
""
],
[
"Bustamante",
"C.",
""
],
[
"Ritort",
"F.",
""
],
[
"Tinoco",
"I.",
"Jr"
]
] |
0707.0581 | Thomas Peternell | Jean-Pierre Demailly, Jun-Muk Hwang, Thomas Peternell | Compact Manifolds Covered by a Torus | final version, to appear in Journal of Geometric Analysis | null | null | null | math.AG | null | Let $X$ be a connected compact complex manifold admitting a finite surjective
map $A \to X$ from a complex torus $A.$ We prove that up to finite \'etale
cover, $X$ is a product of projective spaces and a torus.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 11:35:54 GMT"
},
{
"version": "v2",
"created": "Mon, 12 Nov 2007 11:03:37 GMT"
},
{
"version": "v3",
"created": "Mon, 25 Feb 2008 08:21:21 GMT"
}
] | 2008-02-25T00:00:00 | [
[
"Demailly",
"Jean-Pierre",
""
],
[
"Hwang",
"Jun-Muk",
""
],
[
"Peternell",
"Thomas",
""
]
] |
0707.0582 | Nazario Tantalo | G.M. de Divitiis, E. Molinaro, R. Petronzio, N. Tantalo | Quenched lattice calculation of the B --> D l nu decay rate | 5 pages, 4 figures, accepted for publication on Phys. Lett. B,
corrected one typo | Phys.Lett.B655:45-49,2007 | 10.1016/j.physletb.2007.08.085 | null | hep-lat hep-ph | null | We calculate, in the continuum limit of quenched lattice QCD, the form factor
that enters in the decay rate of the semileptonic decay B --> D l nu. Making
use of the step scaling method (SSM), previously introduced to handle two scale
problems in lattice QCD, and of flavour twisted boundary conditions we extract
G(w) at finite momentum transfer and at the physical values of the heavy quark
masses. Our results can be used in order to extract the CKM matrix element Vcb
by the experimental decay rate without model dependent extrapolations.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:16:38 GMT"
},
{
"version": "v2",
"created": "Wed, 3 Oct 2007 07:54:24 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"de Divitiis",
"G. M.",
""
],
[
"Molinaro",
"E.",
""
],
[
"Petronzio",
"R.",
""
],
[
"Tantalo",
"N.",
""
]
] |
0707.0583 | Oliver Burmeister | A. Bunkowski, O. Burmeister, P. Beyersdorf, K. Danzmann, R. Schnabel,
T. Clausnitzer, E.-B. Kley, and A. T\"unnermann | Low-loss grating for coupling to a high-finesse cavity | null | Optics Letters 29, 2342 (2004) | 10.1364/OL.29.002342 | null | physics.optics | null | A concept for a low loss all-reflective cavity coupler is experimentally
demonstrated at a wavelength of 1064 nm. A 1450 nm period dielectric reflection
grating with a diffraction efficiency of 0.58 % in the -1st order is used in
2nd order Littrow configuration as a coupler to form a cavity with a finesse of
400. The application of such reflective low-loss cavity couplers in future
generations of gravitational-wave detectors as well as some implementation
issues are discussed.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:39:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bunkowski",
"A.",
""
],
[
"Burmeister",
"O.",
""
],
[
"Beyersdorf",
"P.",
""
],
[
"Danzmann",
"K.",
""
],
[
"Schnabel",
"R.",
""
],
[
"Clausnitzer",
"T.",
""
],
[
"Kley",
"E. -B.",
""
],
[
"Tünnermann",
"A.",
""
]
] |
0707.0584 | A. Sherman | Alexei Sherman and Michael Schreiber | Magnetic susceptibility of the two-dimensional Hubbard model using a
power series for the hopping constant | 12 pages, 11 figures | Phys. Rev. B 76, 245112 (2007) | 10.1103/PhysRevB.76.245112 | null | cond-mat.str-el | null | The magnetic susceptibility of the two-dimensional repulsive Hubbard model
with nearest-neighbor hopping is investigated using the diagram technique
developed for the case of strong correlations. In this technique a power series
in the hopping constant is used. At half-filling the calculated zero-frequency
susceptibility and the square of the site spin reproduce adequately results of
Monte Carlo simulations. Also in agreement with numerical simulations no
evidence of ferromagnetic correlations was found in the considered range of
electron concentrations $0.8\alt\bar{n}\alt 1.2$ for the repulsion parameters
$8|t|\leq U\leq 16|t|$. However, for larger $U/|t|$ and $|1-\bar{n}|\approx
0.2$ the nearest neighbor correlations become ferromagnetic. For $\bar{n}\alt
0.94$ and $\bar{n}\agt 1.06$ the imaginary part of the real-frequency
susceptibility becomes incommensurate for small frequencies. The
incommensurability parameter grows with departure from half-filling and
decreases with increasing the frequency. This behavior of the susceptibility
can explain the observed low-frequency incommensurate response observed in
normal-state lanthanum cuprates.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 11:53:17 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Oct 2007 07:47:28 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sherman",
"Alexei",
""
],
[
"Schreiber",
"Michael",
""
]
] |
0707.0585 | Sergei Maydanyuk | Sergei P. Maydanyuk | Wave function of the Universe in the early stage of its evolution | 19 pages, 21 files for 10 EPS figures, LaTeX svjour style. The Sec.2
(formalism of Wheeler-De Witt equation) is reduced. In Sec.3.1 definition of
the outgoing wave from barrier is defined more accurately. In Sec.4.1
semiclassical calculations of wavew function and penetrability are performed
and comparison with results in fully quantum approach is added | Eur.Phys.J.C57:769-784,2008 | 10.1140/epjc/s10052-008-0723-2 | null | gr-qc astro-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In quantum cosmological models, constructed in the framework of
Friedmann-Robertson-Walker metrics, a nucleation of the Universe with its
further expansion is described as a tunneling transition through an effective
barrier between regions with small and large values of the scale factor $a$ at
non-zero (or zero) energy. The approach for describing this tunneling consists
of constructing a wave function satisfying an appropriate boundary condition.
There are various ways for defining the boundary condition that lead to
different estimates of the barrier penetrability and the tunneling time.
In order to describe the escape from the tunneling region as accurately as
possible and to construct the total wave function on the basis of its two
partial solutions unambiguously, we use the tunneling boundary condition that
the total wave function must represent only the outgoing wave at the point of
escape from the barrier, where the following definition for the wave is
introduced: the wave is represented by the wave function whose modulus changes
minimally under a variation of the scale factor $a$. We construct a new method
for a direct non-semiclassical calculation of the total stationary wave
function of the Universe, analyze the behavior of this wave function in the
tunneling region, near the escape point and in the asymptotic region, and
estimate the barrier penetrability. We observe oscillations of modulus of wave
function in the external region starting from the turning point which decrease
with increasing of $a$ and which are not shown in semiclassical calculations.
The period of such an oscillation decreases uniformly with increasing $a$ and
can be used as a fully quantum dynamical characteristic of the expansion of the
Universe.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 15:38:16 GMT"
},
{
"version": "v2",
"created": "Mon, 18 Aug 2008 07:13:20 GMT"
},
{
"version": "v3",
"created": "Fri, 28 Nov 2008 08:33:21 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Maydanyuk",
"Sergei P.",
""
]
] |
0707.0586 | Csaba Toke Dr. | Csaba Toke, Nicolas Regnault, Jainendra K. Jain | Numerical studies of the Pfaffian model of the nu=5/2 fractional quantum
Hall effect | one column removed from Table II. Solid State Communications, in
press | Solid State Communications, 144, 504 (2007) | 10.1016/j.ssc.2007.03.061 | null | cond-mat.mes-hall cond-mat.str-el | null | The Pfaffian model has been proposed for the fractional quantum Hall effect
(FQHE) at nu=5/2. We examine it for the quasihole excitations by comparison
with exact diagonalization results. Specifically, we consider the structure of
the low-energy spectrum, accuracy of the microscopic wave functions,
particle-hole symmetry, splitting of the degeneracies, and off-diagonal long
range order. We also review how the 5/2 FQHE can be understood without
appealing to the Pfaffian model. Implications for nonabelian braiding
statistics will be mentioned.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:07:14 GMT"
},
{
"version": "v2",
"created": "Wed, 18 Jul 2007 07:57:59 GMT"
}
] | 2010-06-24T00:00:00 | [
[
"Toke",
"Csaba",
""
],
[
"Regnault",
"Nicolas",
""
],
[
"Jain",
"Jainendra K.",
""
]
] |
0707.0587 | Nazario Tantalo | G.M. de Divitiis, R. Petronzio, N. Tantalo | Quenched lattice calculation of semileptonic heavy-light meson form
factors | 16 pages, 10 figures, version accepted for publication on JHEP | JHEP0710:062,2007 | 10.1088/1126-6708/2007/10/062 | null | hep-lat hep-ph | null | We calculate, in the continuum limit of quenched lattice QCD, the matrix
elements of the heavy-heavy vector current between heavy-light pseudoscalar
meson states. We present the form factors for different values of the initial
and final meson masses at finite momentum transfer. In particular, we calculate
the non-perturbative correction to the differential decay rate of the process B
--> D l nu including the case of a non-vanishing lepton mass.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:10:47 GMT"
},
{
"version": "v2",
"created": "Wed, 3 Oct 2007 08:03:32 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"de Divitiis",
"G. M.",
""
],
[
"Petronzio",
"R.",
""
],
[
"Tantalo",
"N.",
""
]
] |
0707.0588 | Mairi Sakellariadou | William Nelson and Mairi Sakellariadou (King's College, London) | Lattice Refining LQC and the Matter Hamiltonian | 15 pages, 3 figures, revtex style; amended version to match
publication in Phys. Rev. D | Phys.Rev.D76:104003,2007 | 10.1103/PhysRevD.76.104003 | null | gr-qc astro-ph hep-ex hep-ph hep-th | null | In the context of loop quantum cosmology, we parametrise the lattice
refinement by a parameter, $A$, and the matter Hamiltonian by a parameter,
$\delta$. We then solve the Hamiltonian constraint for both a self-adjoint, and
a non-self-adjoint Hamiltonian operator. Demanding that the solutions for the
wave-functions obey certain physical restrictions, we impose constraints on the
two-dimensional, $(A,\delta)$, parameter space, thereby restricting the types
of matter content that can be supported by a particular lattice refinement
model.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:11:43 GMT"
},
{
"version": "v2",
"created": "Thu, 30 Aug 2007 11:17:33 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Nelson",
"William",
"",
"King's College, London"
],
[
"Sakellariadou",
"Mairi",
"",
"King's College, London"
]
] |
0707.0589 | Patrick Lukens | T. Aaltonen, et al (for the CDF Collaboration) | Observation and Mass Measurement of the Baryon $\Xi^-_b$ | Minor text changes for the second version. Accepted by Phys. Rev.
Lett | Phys.Rev.Lett.99:052002,2007 | 10.1103/PhysRevLett.99.052002 | Fermilab-Pub-07-336-E | hep-ex | null | We report the observation and measurement of the mass of the bottom, strange
baryon $\Xi^-_b$ through the decay chain $\Xi^-_b \to J/\psi \Xi^-$, where
$J/\psi \to \mu^+ \mu^-$, $\Xi^- \to \Lambda \pi^-$, and $\Lambda \to p \pi^-$.
Evidence for observation is based on a signal whose probability of arising from
the estimated background is 6.6 x 10^{-15}, or 7.7 Gaussian standard
deviations. The $\Xi^-_b$ mass is measured to be $5792.9\pm 2.5$ (stat.) $\pm
1.7$ (syst.) MeV/$c^2$.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:11:44 GMT"
},
{
"version": "v2",
"created": "Mon, 30 Jul 2007 16:44:54 GMT"
}
] | 2019-08-13T00:00:00 | [
[
"Aaltonen",
"T.",
""
]
] |
0707.0590 | Francesco Marzari Dr. | F. Marzari (Dept. Physics, Univ. Padova), M. Barbieri (LAM, Marseille,
France) | Dispersal of planets hosted in binaries, transitional members of
multiple star systems | 6 pages, 5 figures | null | null | null | astro-ph | null | This paper explains why planets in binary star systems might have a lower
frequency. A transient triple state of the binary causes the dispersal of
planets.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:13:56 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Marzari",
"F.",
"",
"Dept. Physics, Univ. Padova"
],
[
"Barbieri",
"M.",
"",
"LAM, Marseille,\n France"
]
] |
0707.0591 | Sandro Sozzo | Jaroslaw Pykacz and Piotr Frackiewicz | Arbiter as the Third Man in classical and quantum games | 4 pages | null | null | null | quant-ph | null | We study possible influence of not necessarily sincere arbiter on the course
of classical and quantum 2x2 games and we show that this influence in the
quantum case is much bigger than in the classical case. Extreme sensitivity of
quantum games on initial states of quantum objects used as carriers of
information in a game shows that a quantum game, contrary to a classical game,
is not defined by a payoff matrix alone but also by an initial state of objects
used to play a game. Therefore, two quantum games that have the same payoff
matrices but begin with different initial states should be considered as
different games.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:15:16 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Pykacz",
"Jaroslaw",
""
],
[
"Frackiewicz",
"Piotr",
""
]
] |
0707.0592 | Szabolcs Tengely | Szabolcs Tengely | Triangles with two given integral sides | null | null | null | null | math.NT | null | We study some Diophantine problems related to triangles with two given
integral sides. We solve two problems posed by Zolt\'an Bertalan and we also
provide some generalization.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:30:01 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Tengely",
"Szabolcs",
""
]
] |
0707.0593 | Szabolcs Tengely | Lajos Hajdu, Szabolcs Tengely | Arithmetic progressions of squares, cubes and $n$-th powers | null | null | null | null | math.NT | null | In this paper we continue the investigations about unlike powers in
arithmetic progression. We provide sharp upper bounds for the length of
primitive non-constant arithmetic progressions consisting of squares/cubes and
$n$-th powers.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:37:18 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Hajdu",
"Lajos",
""
],
[
"Tengely",
"Szabolcs",
""
]
] |
0707.0594 | Ian Howarth | Ian D. Howarth, Nolan R. Walborn, Danny J. Lennon, Joachim Puls, Yael
Naze, K. Annuk, I. Antokhin, D. Bohlender, H. Bond, J.-F. Donati, L.
Georgiev, D. Gies, D. Harmer, A. Herrero, I. Kolka, D. McDavid, T. Morel, I.
Negueruela, G. Rauw, P. Reig | Towards an understanding of the Of?p star HD 191612: optical
spectroscopy | Accepted for MNRAS | MNRAS, 381, 433-446 (2007) | 10.1111/j.1365-2966.2007.12178.x | null | astro-ph | null | We present extensive optical spectroscopy of the early-type magnetic star HD
191612 (O6.5f?pe-O8fp). The Balmer and HeI lines show strongly variable
emission which is highly reproducible on a well-determined 538-d period. Metal
lines and HeII absorptions (including many selective emission lines but
excluding He II 4686A emission) are essentially constant in line strength, but
are variable in velocity, establishing a double-lined binary orbit with P(orb)
= 1542d, e=0.45. We conduct a model-atmosphere analysis of the primary, and
find that the system is consistent with a O8: giant with a B1: main-sequence
secondary. Since the periodic 538-d changes are unrelated to orbital motion,
rotational modulation of a magnetically constrained plasma is strongly favoured
as the most likely underlying `clock'. An upper limit on the equatorial
rotation is consistent with this hypothesis, but is too weak to provide a
strong constraint.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:39:14 GMT"
}
] | 2020-12-10T00:00:00 | [
[
"Howarth",
"Ian D.",
""
],
[
"Walborn",
"Nolan R.",
""
],
[
"Lennon",
"Danny J.",
""
],
[
"Puls",
"Joachim",
""
],
[
"Naze",
"Yael",
""
],
[
"Annuk",
"K.",
""
],
[
"Antokhin",
"I.",
""
],
[
"Bohlender",
"D.",
""
],
[
"Bond",
"H.",
""
],
[
"Donati",
"J. -F.",
""
],
[
"Georgiev",
"L.",
""
],
[
"Gies",
"D.",
""
],
[
"Harmer",
"D.",
""
],
[
"Herrero",
"A.",
""
],
[
"Kolka",
"I.",
""
],
[
"McDavid",
"D.",
""
],
[
"Morel",
"T.",
""
],
[
"Negueruela",
"I.",
""
],
[
"Rauw",
"G.",
""
],
[
"Reig",
"P.",
""
]
] |
0707.0595 | Geetanjali Sarkar (Gauba) | G. Sarkar, M. Parthasarathy, P. Garcia-Lario | High resolution spectroscopy of the high velocity hot post-AGB star LS
III +52 24 (IRAS 22023+5249) | This article is superseded by arXiv:1112.1326 to appear in MNRAS | null | null | null | astro-ph | null | Aims: To investigate the first high resolution optical spectrum of the B-type
star, LS III +52 24, identified as the optical counterpart of the hot post-AGB
candidate IRAS 22023+5249 (I22023).
Methods: We carried out detailed identifications of the observed absorption
and emission features in the high resolution spectrum (4290 - 9015 A) of I22023
obtained with the Utrecht Echelle Spectrograph on the 4.2m William Herschel
Telescope. Using Kurucz's WIDTH9 program and the spectrum synthesis code,
SYNSPEC, we determined the atmospheric parameters and abundances. The
photospheric abundances were derived under the LTE approximation. The NEBULAR
package under IRAF was used to estimate the electron temperature (T_e) and the
electron density (N_e) from the [N II] and [S II] lines.
Results: We estimated T_eff=24000 K, log g=3.0, xi_t=7 kms^{-1}. The derived
CNO abundances suggest an evolved star with C/O < 1. P-Cygni profiles of
hydrogen and helium indicate ongoing post-AGB mass loss. The presence of [N II]
and [S II] lines and the non-detection of [O III] indicate that photoionisation
has just started. The derived nebular parameters T_e=7000 K, N_e=1.2X10^{4}
cm^{-3} are comparable to those measured in young, compact planetary nebulae
(PNe). The nebular expansion velocity was estimated to be 17.5 kms^{-1}.
Conclusions: The observed spectral features, large heliocentric radial
velocity (-148.31 +/- 0.60 kms^{-1}), atmospheric parameters and chemical
composition indicate that I22023, at a distance of 1.95 kpc, is an evolved
post-AGB star belonging to the old disk population. The nebular parameters
suggest that the central star may be evolving into a compact, young PN, similar
to Hen3-1357.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:45:46 GMT"
},
{
"version": "v2",
"created": "Fri, 30 Dec 2011 17:51:26 GMT"
}
] | 2012-01-04T00:00:00 | [
[
"Sarkar",
"G.",
""
],
[
"Parthasarathy",
"M.",
""
],
[
"Garcia-Lario",
"P.",
""
]
] |
0707.0596 | Szabolcs Tengely | Szabolcs Tengely | Note on a paper "An Extension of a Theorem of Euler" by Hirata-Kohno et
al | null | null | 10.4064/aa134-4-3 | null | math.NT | null | In this paper we extend a result of Hirata-Kohno, Laishram, Shorey and
Tijdeman on the Diophantine equation $n(n+d)...(n+(k-1)d)=by^2,$ where
$n,d,k\geq 2$ and $y$ are positive integers such that $\gcd(n,d)=1.$
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:46:36 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Tengely",
"Szabolcs",
""
]
] |
0707.0597 | Neil Seshadri | Neil Seshadri | Approximately Einstein ACH metrics, volume renormalization, and an
invariant for contact manifolds | Minor typographical corrections | Bull. Soc. Math. France 137 (2009) 63--91 | null | null | math.DG | null | To any smooth compact manifold $M$ endowed with a contact structure $H$ and
partially integrable almost CR structure $J$, we prove the existence and
uniqueness, modulo high-order error terms and diffeomorphism action, of an
approximately Einstein ACH (asymptotically complex hyperbolic) metric $g$ on
$M\times (-1,0)$.
We consider the asymptotic expansion, in powers of a special defining
function, of the volume of $M\times (-1,0)$ with respect to $g$ and prove that
the log term coefficient is independent of $J$ (and any choice of contact form
$\theta$), i.e., is an invariant of the contact structure $H$.
The approximately Einstein ACH metric $g$ is a generalisation of, and
exhibits similar asymptotic boundary behaviour to, Fefferman's approximately
Einstein complete K\"ahler metric $g_+$ on strictly pseudoconvex domains. The
present work demonstrates that the CR-invariant log term coefficient in the
asymptotic volume expansion of $g_+$ is in fact a contact invariant. We discuss
some implications this may have for CR $Q$-curvature.
The formal power series method of finding $g$ is obstructed at finite order.
We show that part of this obstruction is given as a one-form on $H^*$. This is
a new result peculiar to the partially integrable setting.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:46:48 GMT"
},
{
"version": "v2",
"created": "Wed, 10 Oct 2007 10:09:25 GMT"
}
] | 2009-04-04T00:00:00 | [
[
"Seshadri",
"Neil",
""
]
] |
0707.0598 | Jerzy Lukasik | J. Lukasik, P. Adrich, T. Aumann, C.O. Bacri, T. Barczyk, R. Bassini,
S. Bianchin, C. Boiano, A.S. Botvina, A. Boudard, J. Brzychczyk, A. Chbihi,
J. Cibor, B. Czech, J.-E. Ducret, H. Emling, J. Frankland, M. Hellstroem, D.
Henzlova, G. Imme, I. Iori, H. Johansson, K. Kezzar, A. Lafriakh, A. Le
Fevre, E. Le Gentil, Y. Leifels, J. Luehning, W.G. Lynch, U. Lynen, Z. Majka,
M. Mocko, W.F.J. Mueller, A. Mykulyak, M. De Napoli, H. Orth, A.N. Otte, R.
Palit, P. Pawlowski, A. Pullia, G. Raciti, E. Rapisarda, H. Sann, C. Schwarz,
C. Sfienti, H. Simon, K. Summerer, W. Trautmann, M.B. Tsang, G. Verde, C.
Volant, M. Wallace, H. Weick, J. Wiechula, A. Wieloch, B. Zwieglinski (The
ALADIN'2000 Collaboration) | Discriminant Analysis and Secondary-Beam Charge Recognition | 6 pages, 7 eps figures, elsart, submitted to Nucl. Instr. and Meth. A | null | 10.1016/j.nima.2008.01.071 | null | nucl-ex | null | The discriminant-analysis method has been applied to optimize the exotic-beam
charge recognition in a projectile fragmentation experiment. The experiment was
carried out at the GSI using the fragment separator (FRS) to produce and select
the relativistic secondary beams, and the ALADIN setup to measure their
fragmentation products following collisions with Sn target nuclei. The beams of
neutron poor isotopes around 124La and 107Sn were selected to study the isospin
dependence of the limiting temperature of heavy nuclei by comparing with
results for stable 124Sn projectiles. A dedicated detector to measure the
projectile charge upstream of the reaction target was not used, and alternative
methods had to be developed. The presented method, based on the multivariate
discriminant analysis, allowed to increase the efficacy of charge recognition
up to about 90%, which was about 20% more than achieved with the simple scalar
methods.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:46:11 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Lukasik",
"J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Adrich",
"P.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Aumann",
"T.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Bacri",
"C. O.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Barczyk",
"T.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Bassini",
"R.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Bianchin",
"S.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Boiano",
"C.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Botvina",
"A. S.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Boudard",
"A.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Brzychczyk",
"J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Chbihi",
"A.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Cibor",
"J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Czech",
"B.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Ducret",
"J. -E.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Emling",
"H.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Frankland",
"J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Hellstroem",
"M.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Henzlova",
"D.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Imme",
"G.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Iori",
"I.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Johansson",
"H.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Kezzar",
"K.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Lafriakh",
"A.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Fevre",
"A. Le",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Gentil",
"E. Le",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Leifels",
"Y.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Luehning",
"J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Lynch",
"W. G.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Lynen",
"U.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Majka",
"Z.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Mocko",
"M.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Mueller",
"W. F. J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Mykulyak",
"A.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"De Napoli",
"M.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Orth",
"H.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Otte",
"A. N.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Palit",
"R.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Pawlowski",
"P.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Pullia",
"A.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Raciti",
"G.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Rapisarda",
"E.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Sann",
"H.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Schwarz",
"C.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Sfienti",
"C.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Simon",
"H.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Summerer",
"K.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Trautmann",
"W.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Tsang",
"M. B.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Verde",
"G.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Volant",
"C.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Wallace",
"M.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Weick",
"H.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Wiechula",
"J.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Wieloch",
"A.",
"",
"The\n ALADIN'2000 Collaboration"
],
[
"Zwieglinski",
"B.",
"",
"The\n ALADIN'2000 Collaboration"
]
] |
0707.0599 | Francois Ducastelle | P\'erine Jaffrennou (LEM, DMPH, LPQM), Julien Barjon (GEMAC),
Jean-S\'ebastien Lauret (LPQM), Brigitte Attal-Tr\'etout (DMPH), Fran\c{c}ois
Ducastelle (LEM), Annick Loiseau (LEM) | Origin of the excitonic recombinations in hexagonal boron nitride by
spatially resolved cathodoluminescence spectroscopy | null | null | 10.1063/1.2821413 | null | cond-mat.mtrl-sci | null | The excitonic recombinations in hexagonal boron nitride (hBN) are
investigated with spatially resolved cathodoluminescence spectroscopy in the UV
range. Cathodoluminescence images of an individual hBN crystallite reveals that
the 215 nm free excitonic line is quite homogeneously emitted along the
crystallite whereas the 220 nm and 227 nm excitonic emissions are located in
specific regions of the crystallite. Transmission electron microscopy images
show that these regions contain a high density of crystalline defects. This
suggests that both the 220 nm and 227 nm emissions are produced by the
recombination of excitons bound to structural defects.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:48:12 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Jaffrennou",
"Périne",
"",
"LEM, DMPH, LPQM"
],
[
"Barjon",
"Julien",
"",
"GEMAC"
],
[
"Lauret",
"Jean-Sébastien",
"",
"LPQM"
],
[
"Attal-Trétout",
"Brigitte",
"",
"DMPH"
],
[
"Ducastelle",
"François",
"",
"LEM"
],
[
"Loiseau",
"Annick",
"",
"LEM"
]
] |
0707.0600 | Marc Artzrouni | Marc Artzrouni (LMA - PAU), Vivient Kamla (LMA - PAU) | Does heterosexual transmission drive the HIV/AIDS epidemic in
Sub-Saharan Africa (or elsewhere)? | null | null | null | null | stat.AP | null | A two-sex Basic Reproduction Number (BRN) is used to investigate the
conditions under which the Human Immunodeficiency Virus (HIV) may spread
through heterosexual contacts in Sub-Saharan Africa. (The BRN is the expected
number of new infections generated by one infected individual; the disease
spreads if the BRN is larger than 1). A simple analytical expression for the
BRN is derived on the basis of recent data on survival rates, transmission
probabilities, and levels of sexual activity. Baseline results show that in the
population at large (characterized by equal numbers of men and women) the BRN
is larger than 1 if every year each person has 82 sexual contacts with
different partners. the BRN is also larger than 1 for commercial sex workers
(CSWs) and their clients (two populations of different sizes) if each CSW has
about 256 clients per year and each client visits one CSW every two weeks. A
sensitivity analysis explores the effect on the BRN of a doubling (or a
halving) of the transmission probabilities. Implications and extensions are
discussed.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:48:46 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Artzrouni",
"Marc",
"",
"LMA - PAU"
],
[
"Kamla",
"Vivient",
"",
"LMA - PAU"
]
] |
0707.0601 | Keun-young Kim | Keun-Young Kim, Sang-Jin Sin, Ismail Zahed | Diffusion in an Expanding Plasma using AdS/CFT | 19 pages, 2 figures, minor corrections, version to appear in JHEP | JHEP0804:047,2008 | 10.1088/1126-6708/2008/04/047 | null | hep-th hep-ph | null | We consider the diffusion of a non-relativistic heavy quark of fixed mass M,
in a one-dimensionally expanding and strongly coupled plasma using the AdS/CFT
duality. The Green's function constructed around a static string embedded in a
background with a moving horizon, is identified with the noise correlation
function in a Langevin approach. The (electric) noise decorrelation is of order
1/T(\tau) while the velocity de-correlation is of order MD(\tau)/T(\tau). For
MD>1, the diffusion regime is segregated and the energy loss is Langevin-like.
The time dependent diffusion constant D(\tau) asymptotes its adiabatic limit
2/\pi\sqrt{\lambda} T(\tau) when \tau/\tau_0=(1/3\eta_0\tau_0)^3 where \eta_0
is the drag coefficient at the initial proper time \tau_0.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 12:57:24 GMT"
},
{
"version": "v2",
"created": "Wed, 9 Apr 2008 19:21:51 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kim",
"Keun-Young",
""
],
[
"Sin",
"Sang-Jin",
""
],
[
"Zahed",
"Ismail",
""
]
] |
0707.0602 | Isabelle Bouchoule | Isabelle Bouchoule (LCFIO), Jean-Baptiste Trebbia (LCFIO), Carlos L.
Garrido Alzar (LCFIO) | Limitation of the modulation method to smooth wire guide roughness | 11 pages | Physical Review A: Atomic, Molecular and Optical Physics 77 (2008)
023624 | 10.1103/PhysRevA.77.023624 | null | cond-mat.other | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It was recently demonstrated that wire guide roughness can be suppressed by
modulating the wire currents so that the atoms experience a time-averaged
potential without roughness. We theoretically study the limitations of this
technique. At low modulation frequency, we show that the longitudinal potential
modulation produces a heating of the cloud and we compute the heating rate. We
also give a quantum derivation of the rough conservative potential associated
with the micro-motion of the atoms. At large modulation frequency, we compute
the loss rate due to non adiabatic spin flip and show it presents resonnances
at multiple modulation frequencies. These studies show that the modulation
technique works for a wide range of experimental parameters. We also give
conditions to realise radio-frequency evaporative cooling in such a modulated
trap.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:00:57 GMT"
},
{
"version": "v2",
"created": "Thu, 18 Nov 2010 09:00:49 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Bouchoule",
"Isabelle",
"",
"LCFIO"
],
[
"Trebbia",
"Jean-Baptiste",
"",
"LCFIO"
],
[
"Alzar",
"Carlos L. Garrido",
"",
"LCFIO"
]
] |
0707.0603 | Bassano Vacchini | Bassano Vacchini | Covariant Mappings for the Description of Measurement, Dissipation and
Decoherence in Quantum Mechanics | Comments: 38 pages, to appear in Lecture Notes in Physics,
Springer-Verlag | Lecture Notes in Physics, vol. 787, pp. 39-77 (2010) | 10.1007/978-3-642-02871-7 | null | quant-ph | null | The general formalism of quantum mechanics for the description of statistical
experiments is briefly reviewed, introducing in particular position and
momentum observables as POVM characterized by their covariance properties with
respect to the isochronous Galilei group. Mappings describing state
transformations both as a consequence of measurement and of dynamical evolution
for a closed or open system are considered with respect to the general
constraints they have to obey and their covariance properties with respect to
symmetry groups. In particular different master equations are analyzed in view
of the related symmetry group, recalling the general structure of mappings
covariant under the same group. This is done for damped harmonic oscillator,
two-level system and quantum Brownian motion. Special attention is devoted to
the general structure of translation-covariant master equations. Within this
framework a recently obtained quantum counterpart of the classical linear
Boltzmann equation is considered, as well as a general theoretical framework
for the description of different decoherence experiments, pointing to a
connection between different possible behaviours in the description of
decoherence and the characteristic functions of classical L\'evy processes.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:08:52 GMT"
}
] | 2009-10-27T00:00:00 | [
[
"Vacchini",
"Bassano",
""
]
] |
0707.0604 | Michael M. Wolf | Michael M. Wolf | Not-so-normal mode decomposition | 4 pages, 2 figures, published version | Phys. Rev. Lett. 100, 070505 (2008) | 10.1103/PhysRevLett.100.070505 | null | quant-ph math-ph math.MP | null | We provide a generalization of the normal mode decomposition for
non-symmetric or locality constrained situations. This allows for instance to
locally decouple a bipartitioned collection of arbitrarily correlated
oscillators up to elementary pairs into which all correlations are condensed.
Similarly, it enables us to decouple the interaction parts of multi-mode
channels into single-mode and pair-interactions where the latter are shown to
be a clear signature of squeezing between system and environment. In
mathematical terms the result is a canonical matrix form with respect to real
symplectic equivalence transformations.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:17:42 GMT"
},
{
"version": "v2",
"created": "Mon, 10 Mar 2008 18:32:56 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wolf",
"Michael M.",
""
]
] |
0707.0605 | Richard Parker | Richard J. Parker and Simon P. Goodwin (Sheffield) | Do O-stars form in isolation? | 6 pages, 5 figures, MNRAS in press | null | 10.1111/j.1365-2966.2007.12179.x | null | astro-ph | null | Around 4% of O-stars are observed in apparent isolation, with no associated
cluster, and no indication of having been ejected from a nearby cluster. We
define an isolated O-star as a star > 17.5 M_\odot in a cluster with total mass
<100 M_\odot which contains no other massive (>10 M_\odot) stars. We show that
the fraction of apparently isolated O-stars is reproduced when stars are
sampled (randomly) from a standard initial mass function and a standard cluster
mass function of the form N(M) \propto M^-2.
This result is difficult to reconcile with the idea that there is a
fundamental relationship between the mass of a cluster and the mass of the most
massive star in that cluster. We suggest that such a relationship is a typical
result of star formation in clusters, and that `isolated O-stars' are low-mass
clusters in which massive stars have been able to form.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:12:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Parker",
"Richard J.",
"",
"Sheffield"
],
[
"Goodwin",
"Simon P.",
"",
"Sheffield"
]
] |
0707.0606 | Federica Masiero | Giuseppina Guatteri, Federica Masiero | Infinite Horizon and Ergodic Optimal Quadratic Control for an Affine
Equation with Stochastic Coefficients | null | Siam Journal on Control and Optimization 48 Issue: 3 (2009)
1600-1631 | null | null | math.PR | null | We study quadratic optimal stochastic control problems with control dependent
noise state equation perturbed by an affine term and with stochastic
coefficients. Both infinite horizon case and ergodic case are treated. To this
purpose we introduce a Backward Stochastic Riccati Equation and a dual backward
stochastic equation, both considered in the whole time line. Besides some
stabilizability conditions we prove existence of a solution for the two
previous equations defined as limit of suitable finite horizon approximating
problems. This allows to perform the synthesis of the optimal control.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:16:26 GMT"
},
{
"version": "v2",
"created": "Mon, 28 Apr 2008 08:59:42 GMT"
}
] | 2013-04-10T00:00:00 | [
[
"Guatteri",
"Giuseppina",
""
],
[
"Masiero",
"Federica",
""
]
] |
0707.0607 | Dominique Manchon | Kurusch Ebrahimi-Fard, Dominique Manchon | A Magnus- and Fer-type formula in dendriform algebras | 13 pages, LaTeX. Terminology issues fixed. Page setup problems fixed
on pdf file. Final version as to appear in Foundations of Computational
Mathematics | Foundations of Computational Mathematics, Volume 9, Issue3 (2009),
295. | 10.1007/s10208-008-9023-3 | null | math.CO math-ph math.CA math.MP math.RA | null | We provide a refined approach to the classical Magnus and Fer expansion,
unveiling a new structure by using the language of dendriform and pre-Lie
algebras. The recursive formula for the logarithm of the solutions of the
equations X=1+ta<X and Y=1-tY> a in A[[t]] is provided, where (A,<,>) is a
dendriform algebra. Then, we present the solutions to these equations as an
infinite product expansion of exponentials. Both formulae involve the pre-Lie
product naturally associated with the dendriform structure. Several
applications are presented.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:16:38 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 13:15:07 GMT"
},
{
"version": "v3",
"created": "Thu, 10 Jan 2008 12:48:59 GMT"
}
] | 2009-04-11T00:00:00 | [
[
"Ebrahimi-Fard",
"Kurusch",
""
],
[
"Manchon",
"Dominique",
""
]
] |
0707.0608 | Matthew J. Case | Matthew J. Case and Vlad Dobrosavljevic | Fluctuation-induced first order transition due to Griffiths anomalies of
the Cluster glass phase | 11 pages, 5 figures, paper to appear in the Proceedings of SPIE
International Conference "Fluctuations and Noise 2007", Florence, Italy,
20-24 May, 2007 | Proc. SPIE Vol. 6600, 66001D (2007) | 10.1117/12.724572 | null | cond-mat.dis-nn | null | In itinerant magnetic systems with disorder, the quantum Griffiths phase at
T=0 is unstable to formation of a cluster glass (CG) of frozen droplet degrees
of freedom. In the absence of the fluctuations associated with these degrees of
freedom, the transition from the paramagnetic Fermi liquid (PMFL) to the
ordered phase proceeds via a conventional second-order quantum phase
transition. However, when the Griffiths anomalies due to the broad distribution
of local energy scales are included, the transition is driven first-order via a
novel mechanism for a fluctuation induced first-order transition. At higher
temperatures, thermal effects restore the transition to second-order.
Implications of the enhanced non-Ohmic dissipation in the CG phase are briefly
discussed.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 19:56:11 GMT"
}
] | 2007-10-22T00:00:00 | [
[
"Case",
"Matthew J.",
""
],
[
"Dobrosavljevic",
"Vlad",
""
]
] |
0707.0609 | Martin Rosvall | M. Rosvall and C. T. Bergstrom | Maps of random walks on complex networks reveal community structure | 7 pages and 4 figures plus supporting material. For associated source
code, see http://www.tp.umu.se/~rosvall/ | PNAS 105, 1118-1123 (2008) | 10.1073/pnas.0706851105 | null | physics.soc-ph cond-mat.dis-nn physics.data-an | null | To comprehend the multipartite organization of large-scale biological and
social systems, we introduce a new information theoretic approach that reveals
community structure in weighted and directed networks. The method decomposes a
network into modules by optimally compressing a description of information
flows on the network. The result is a map that both simplifies and highlights
the regularities in the structure and their relationships. We illustrate the
method by making a map of scientific communication as captured in the citation
patterns of more than 6000 journals. We discover a multicentric organization
with fields that vary dramatically in size and degree of integration into the
network of science. Along the backbone of the network -- including physics,
chemistry, molecular biology, and medicine -- information flows
bidirectionally, but the map reveals a directional pattern of citation from the
applied fields to the basic sciences.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:23:03 GMT"
},
{
"version": "v2",
"created": "Wed, 8 Aug 2007 18:31:02 GMT"
},
{
"version": "v3",
"created": "Mon, 12 Nov 2007 05:46:58 GMT"
}
] | 2008-02-13T00:00:00 | [
[
"Rosvall",
"M.",
""
],
[
"Bergstrom",
"C. T.",
""
]
] |
0707.0610 | Joseph O'Rourke | Joseph O'Rourke | Unfolding Orthogonal Terrains | 7 pages, 7 figures, 5 references. First revision adds Figure 7, and
improves Figure 6. Second revision further improves Figure 7, and adds one
clarifying sentence. Third corrects label in Figure 7. Fourth revision
corrects a sentence in the conclusion about the class of shapes now known to
be grid-unfoldable | null | null | Smith Technical Report 084 | cs.CG | null | It is shown that every orthogonal terrain, i.e., an orthogonal (right-angled)
polyhedron based on a rectangle that meets every vertical line in a segment,
has a grid unfolding: its surface may be unfolded to a single non-overlapping
piece by cutting along grid edges defined by coordinate planes through every
vertex.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 15:04:33 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 18:11:20 GMT"
},
{
"version": "v3",
"created": "Fri, 6 Jul 2007 12:39:04 GMT"
},
{
"version": "v4",
"created": "Thu, 12 Jul 2007 13:16:38 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"O'Rourke",
"Joseph",
""
]
] |
0707.0611 | Erin K. S. Hicks | E. K. S. Hicks (1,2), M. A. Malkan (1) ((1) University of California,
Los Angeles, (2) Max Planck Institut fuer extraterrestrische Physik) | Circumnuclear Gas in Seyfert 1 Galaxies: Morphology, Kinematics, and
Direct Measurement of Black Hole Masses | 43 pages, including 47 figures; Accepted for publication in ApJ. All
2-D maps (in high resolution) are available at
http://www.astro.ucla.edu/~ehicks . Minor changes to the text and updated
reverberation mapped black hole mass estimates; the conclusions are unchanged | null | 10.1086/521650 | null | astro-ph | null | (Abridged) The two-dimensional distribution and kinematics of the molecular,
ionized, and highly ionized gas in the nuclear regions of Seyfert 1 galaxies
have been measured using high spatial resolution (~0''.09) near-infrared
spectroscopy from NIRSPEC with adaptive optics on the Keck telescope. Molecular
hydrogen, H2, is detected in all nine Seyfert 1 galaxies and, in the majority
of galaxies, has a spatially resolved flux distribution. In contrast, the
narrow component of the BrG emission has a distribution consistent with that of
the K-band continuum. In general, the kinematics of H2 are consistent with thin
disk rotation, with a velocity gradient of over 100 km/s measured across the
central 0''.5 in three galaxies, and across the central 1''.5 in two galaxies.
The kinematics of BrG are in agreement with the H2 rotation, except in all four
cases the central 0''.5 is either blue- or redshifted by more than 75 km/s. The
highly ionized gas, measured with the [Ca VIII] and [Si VII] coronal lines, is
spatially and kinematically consistent with BrG in the central 0''.5. Dynamical
models have been fitted to the two-dimensional H2 kinematics, taking into
account the stellar mass distribution, the emission line flux distribution, and
the point spread function. For NGC 3227 the modeling indicates a black hole
mass of Mbh = 2.0{+1.0/-0.4} x 10^7 Msun, and for NGC 4151 Mbh =
3.0{+0.75/-2.2} x 10^7 Msun. In NGC 7469 the best fit model gives Mbh < 5.0 x
10^7 Msun. In all three galaxies, modeling suggests a near face-on disk
inclination angle, which is consistent with the unification theory of active
galaxies. The direct black hole mass estimates verify that masses determined
from the technique of reverberation mapping are accurate to within a factor of
three with no additional systematic errors.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 16:51:21 GMT"
},
{
"version": "v2",
"created": "Fri, 14 Dec 2007 16:23:06 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Hicks",
"E. K. S.",
""
],
[
"Malkan",
"M. A.",
""
]
] |
0707.0612 | Ross Pinsky | Iddo Ben Ari and Ross Pinsky | Spectral Analysis of a Family of Second-Order Elliptic Operators with
Nonlocal Boundary Condition Indexed by a Probabilty Measure | To appear in the Journal of Functional Analysis | null | null | null | math.SP math.AP | null | Let $D\subset R^d$ be a bounded domain and let \[ L=\frac12\nabla\cdot
a\nabla +b\cdot\nabla \] %\[
%L=\frac12\sum_{i,j=1}^da_{i,j}\frac{\partial^2}{\partial x_i\partial
x_j}+\sum_{i=1}^db_i\frac{\partial}{\partial x_i}, %\] be a second order
elliptic operator on $D$. Let $\nu$ be a probability measure on $D$.
Denote by ${\mathcal L}$ the differential operator whose domain is specified
by the following non-local boundary condition: $$ {\mathcal D_{{\mathcal
L}}}=\{f\in C^2(\ol{D}): \int_D f d\nu = f|_{\partial D}\}, $$ and which
coincides with $L$ on its domain. It is known that $\mathcal L$ possesses an
infinite sequence of eigenvalues, and that with the exception of the zero
eigenvalue, all eigenvalues have negative real part. Define the spectral gap of
$\mathcal {L}$, indexed by $\nu$, by
\gamma_1(\nu)\equiv\sup\{\re \lambda:0\neq \lambda is an eigenvalue for
{\mathcal L}\}.
In this paper we investigate the eigenvalues of $\mathcal L$ in general and
the spectral gap $\gamma_1(\nu)$ in particular. The operator $\mathcal L$ is
the generator of a diffusion process with random jumps from the boundary, and
$\gamma_1(\nu)$ measures the exponential rate of convergence of this process to
its invariant measure.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:51:20 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Ari",
"Iddo Ben",
""
],
[
"Pinsky",
"Ross",
""
]
] |
0707.0613 | Murray Batchelor | X.-W. Guan, M.T. Batchelor and M. Takahashi | Ferromagnetic behaviour in the strongly interacting two-component Bose
gas | 15 pages, 6 figures, revised version, references added, minor
corrections | Phys. Rev. A 76 (2007) 043617 | 10.1103/PhysRevA.76.043617 | null | cond-mat.stat-mech cond-mat.str-el | null | We investigate the low temperature behaviour of the integrable 1D
two-component spinor Bose gas using the thermodynamic Bethe ansatz. We find
that for strong coupling the characteristics of the thermodynamics at low
temperatures are quantitatively affected by the spin ferromagnetic states,
which are described by an effective ferromagnetic Heisenberg chain. The free
energy, specific heat, susceptibility and local pair correlation function are
calculated for various physical regimes in terms of temperature and interaction
strength. These thermodynamic properties reveal spin effects which are
significantly different than those of the spinless Bose gas. The zero-field
susceptibility for finite strong repulsion exceeds that of a free spin
paramagnet. The critical exponents of the specific heat $c_v \sim T^{1/2}$ and
the susceptibility $\chi \sim T^{-2}$ are indicative of the ferromagnetic
signature of the two-component spinor Bose gas. Our analytic results are
consistent with general arguments by Eisenberg and Lieb for polarized spinor
bosons.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:58:13 GMT"
},
{
"version": "v2",
"created": "Tue, 18 Sep 2007 04:58:15 GMT"
}
] | 2007-10-22T00:00:00 | [
[
"Guan",
"X. -W.",
""
],
[
"Batchelor",
"M. T.",
""
],
[
"Takahashi",
"M.",
""
]
] |
0707.0614 | Samson Saneblidze | Samson Saneblidze | The bitwisted Cartesian model for the free loop fibration | 19 pages, 3 figures, Published in "Topology and Its Applications,"
156 (2009), 897-910 | null | null | null | math.AT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the notion of truncating twisting function from a simplicial set to a
cubical set a special, bitwisted, Cartesian product of these sets is defined.
For the universal truncating twisting function, the (co)chain complex of the
corresponding bitwisted Cartesian product agrees with the standard Cartier
(Hochschild) chain complex of the simplicial (co)chains. The modelling
polytopes $F_n$ are constructed. An explicit diagonal on $F_n$ is defined and a
multiplicative model for the free loop fibration $\Omega Y\to \Lambda Y\to Y$
is obtained. As an application we establish an algebra isomorphism $H^*(\Lambda
Y;\mathbb{Z}) \approx S(U)\otimes \Lambda(s^{_{-1}}U)$ for the polynomial
cohomology algebra $H^*(Y;\mathbb{Z})=S(U).$
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:02:00 GMT"
},
{
"version": "v2",
"created": "Fri, 6 Jul 2007 12:54:06 GMT"
},
{
"version": "v3",
"created": "Sat, 7 Jul 2007 16:23:03 GMT"
},
{
"version": "v4",
"created": "Fri, 26 Oct 2007 12:20:15 GMT"
},
{
"version": "v5",
"created": "Sun, 28 Oct 2007 15:20:33 GMT"
},
{
"version": "v6",
"created": "Tue, 18 Mar 2008 15:57:38 GMT"
},
{
"version": "v7",
"created": "Tue, 28 Oct 2008 17:55:53 GMT"
},
{
"version": "v8",
"created": "Fri, 15 May 2009 18:10:23 GMT"
}
] | 2009-05-15T00:00:00 | [
[
"Saneblidze",
"Samson",
""
]
] |
0707.0615 | Claus Kiefer | Claus Kiefer, Gerhard Kolland | Gibbs' paradox and black-hole entropy | Contribution to Mashhoon festschrift, 13 pages, 4 figures | Gen.Rel.Grav.40:1327-1339,2008 | 10.1007/s10714-008-0609-5 | null | gr-qc | null | In statistical mechanics Gibbs' paradox is avoided if the particles of a gas
are assumed to be indistinguishable. The resulting entropy then agrees with the
empirically tested thermodynamic entropy up to a term proportional to the
logarithm of the particle number. We discuss here how analogous situations
arise in the statistical foundation of black-hole entropy. Depending on the
underlying approach to quantum gravity, the fundamental objects to be counted
have to be assumed indistinguishable or not in order to arrive at the
Bekenstein--Hawking entropy. We also show that the logarithmic corrections to
this entropy, including their signs, can be understood along the lines of
standard statistical mechanics. We illustrate the general concepts within the
area quantization model of Bekenstein and Mukhanov.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:02:55 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kiefer",
"Claus",
""
],
[
"Kolland",
"Gerhard",
""
]
] |
0707.0616 | Pawe{\l} Pre\'s | P. Pre\'s and S. Ko{\l}oma\'nski | Geometrical and Physical Properties of SXR Loop-Top Flare Kernels | null | null | null | null | astro-ph | null | We investigate how the geometrical and physical properties of soft X-ray
flare kernels change with their altitude above the photosphere. We analyze limb
flares well observed by {\em Yohkoh}/SXT showing clear geometry with well
separated loop-top kernels. Our analysis concerns relations between kernel
size, plasma pressure, energy release and the kernel altitude. We define
scaling laws describing how the sizes and its physical properties of kernels
vary with the altitude above the photosphere. We interpret the observed
relations in terms of the general magnetic structure of active regions.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:16:46 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Preś",
"P.",
""
],
[
"Kołomański",
"S.",
""
]
] |
0707.0617 | Francesco Marzari Dr. | F. Marzari (Dept. of Physics, Univ. of Padova, Italy), H. Scholl (Obs.
de la Cote d'Azur, Nice, France) | Dynamics of Jupiter Trojans during the 2:1 mean motion resonance
crossing of Jupiter and Saturn | 10 pages, 17 figures | null | 10.1111/j.1365-2966.2007.12095.x | null | astro-ph | null | We study the dynamics of Jupiter Trojans in the early phase of the Solar
system while the outer planets migrated due to their interaction with the
planetesimal disk.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 13:05:36 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Marzari",
"F.",
"",
"Dept. of Physics, Univ. of Padova, Italy"
],
[
"Scholl",
"H.",
"",
"Obs.\n de la Cote d'Azur, Nice, France"
]
] |
0707.0618 | Howard Baer | Howard Baer, Andrew Box, Eun-Kyung Park and Xerxes Tata | Implications of Compressed Supersymmetry for Collider and Dark Matter
Searches | 22 pages including 24 eps figures | JHEP 0708:060,2007 | 10.1088/1126-6708/2007/08/060 | FSU-HEP-070704, UH-511-1108-07 | hep-ph | null | Martin has proposed a scenario dubbed ``compressed supersymmetry'' (SUSY)
where the MSSM is the effective field theory between energy scales M_{\rm weak}
and M_{\rm GUT}, but with the GUT scale SU(3) gaugino mass M_3<< M_1 or M_2. As
a result, squark and gluino masses are suppressed relative to slepton, chargino
and neutralino masses, leading to a compressed sparticle mass spectrum, and
where the dark matter relic density in the early universe may be dominantly
governed by neutralino annihilation into ttbar pairs via exchange of a light
top squark. We explore the dark matter and collider signals expected from
compressed SUSY for two distinct model lines with differing assumptions about
GUT scale gaugino mass parameters. For dark matter signals, the compressed
squark spectrum leads to an enhancement in direct detection rates compared to
models with unified gaugino masses. Meanwhile, neutralino halo annihilation
rates to gamma rays and anti-matter are also enhanced relative to related
scenarios with unified gaugino masses but, depending on the halo dark matter
distribution, may yet be below the sensitivity of indirect searches underway.
In the case of collider signals, we compare the rates for the potentially
dominant decay modes of the stop_1 which may be expected to be produced in
cascade decay chains at the LHC: \tst_1\to c\tz_1 and \tst_1\to bW\tz_1. We
examine the extent to which multilepton signal rates are reduced when the
two-body decay mode dominates. For the model lines that we examine here, the
multi-lepton signals, though reduced, still remain observable at the LHC.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:07:18 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Baer",
"Howard",
""
],
[
"Box",
"Andrew",
""
],
[
"Park",
"Eun-Kyung",
""
],
[
"Tata",
"Xerxes",
""
]
] |
0707.0619 | Maria Jo\~ao Oliveira | Dmitri L. Finkelshtein, Yuri G. Kondratiev, Maria Joao Oliveira | Markov evolutions and hierarchical equations in the continuum I.
One-component systems | 47 pages | J. Evol. Equ. 9 (2) (2009), 197-233 | 10.1007/s00028-009-0007-9 | null | math-ph math.MP | null | General birth-and-death as well as hopping stochastic dynamics of infinite
particle systems in the continuum are considered. We derive corresponding
evolution equations for correlation functions and generating functionals.
General considerations are illustrated in a number of concrete examples of
Markov evolutions appearing in applications.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:14:10 GMT"
}
] | 2010-02-10T00:00:00 | [
[
"Finkelshtein",
"Dmitri L.",
""
],
[
"Kondratiev",
"Yuri G.",
""
],
[
"Oliveira",
"Maria Joao",
""
]
] |
0707.0620 | Jonathan Barrett | Howard Barnum, Jonathan Barrett, Matthew Leifer and Alexander Wilce | A generalized no-broadcasting theorem | 4 pages | Phys. Rev. Lett. 99:240501 (2007) | 10.1103/PhysRevLett.99.240501 | null | quant-ph | null | We prove a generalized version of the no-broadcasting theorem, applicable to
essentially \emph{any} nonclassical finite-dimensional probabilistic model
satisfying a no-signaling criterion, including ones with ``super-quantum''
correlations. A strengthened version of the quantum no-broadcasting theorem
follows, and its proof is significantly simpler than existing proofs of the
no-broadcasting theorem.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 19:59:54 GMT"
}
] | 2008-11-06T00:00:00 | [
[
"Barnum",
"Howard",
""
],
[
"Barrett",
"Jonathan",
""
],
[
"Leifer",
"Matthew",
""
],
[
"Wilce",
"Alexander",
""
]
] |
0707.0621 | Oliver Burmeister | A. Bunkowski, O. Burmeister, K. Danzmann, R. Schnabel, T. Clausnitzer,
E.-B. Kley, A. T\"unnermann | Diffractive Optics for Gravitational Wave Detectors | null | J.Phys.Conf.Ser.32:333-338,2006 | 10.1088/1742-6596/32/1/051 | null | physics.optics | null | All-reflective interferometry based on nano-structured diffraction gratings
offers new possibilities for gravitational wave detection. We investigate an
all-reflective Fabry-Perot interferometer concept in 2nd order Littrow mount.
The input-output relations for such a resonator are derived treating the
grating coupler by means of a scattering matrix formalism. A low loss
dielectric reflection grating has been designed and manufactured to test the
properties of such a grating cavity.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:16:26 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bunkowski",
"A.",
""
],
[
"Burmeister",
"O.",
""
],
[
"Danzmann",
"K.",
""
],
[
"Schnabel",
"R.",
""
],
[
"Clausnitzer",
"T.",
""
],
[
"Kley",
"E. -B.",
""
],
[
"Tünnermann",
"A.",
""
]
] |
0707.0622 | Leszek Roszkowski | Leszek Roszkowski (Sheffield), Roberto Ruiz de Austri (Autonoma
Madrid), Joe Silk (Oxford) and Roberto Trotta (Oxford) | On prospects for dark matter indirect detection in the Constrained MSSM | final PLB version, discussion of prior dependence added, paper based
on a new software tool SuperBayeS (available from http://superbayes.org) | Phys.Lett.B671:10-14,2009 | 10.1016/j.physletb.2008.11.061 | null | astro-ph hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of the Constrained MSSM we derive the most probable ranges
of the diffuse gamma radiation flux from the direction of the Galactic center
and of the positron flux from the Galactic halo due to neutralino dark matter
annihilation. We find that, for a given halo model, and assuming flat priors,
the 68% probability range of the integrated gamma-ray flux spans about one
order of magnitude, while the 95% probability range can be much larger and
extend over four orders of magnitude (even exceeding five for a tiny region at
small neutralino mass). The detectability of the signal by GLAST depending
primarily on the cuspiness of the halo profile. The positron flux, on the other
hand, appears to be too small to be detectable by PAMELA, unless the boost
factor is at least of order ten and/or the halo profile is extremely cuspy. We
also briefly discuss the sensitivity of our results to the choice of priors.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:17:18 GMT"
},
{
"version": "v2",
"created": "Fri, 14 Nov 2008 20:36:35 GMT"
}
] | 2009-01-16T00:00:00 | [
[
"Roszkowski",
"Leszek",
"",
"Sheffield"
],
[
"de Austri",
"Roberto Ruiz",
"",
"Autonoma\n Madrid"
],
[
"Silk",
"Joe",
"",
"Oxford"
],
[
"Trotta",
"Roberto",
"",
"Oxford"
]
] |
0707.0623 | Jan Kuipers | K. Brendel (1), J. Kuipers (1), G.T. Barkema (1), P. Hoyng (2) ((1)
Utrecht University, (2) SRON Netherlands Institute for Space Research) | An analysis of the fluctuations of the geomagnetic dipole | 11 pages, 6 figures | Phys. Earth Planet. Inter. 162 (2007) 249-255 | 10.1016/j.pepi.2007.05.005 | ITP-UU-07/33 | physics.geo-ph | null | The time evolution of the strength of the Earth's virtual axial dipole moment
(VADM) is analyzed by relating it to the Fokker-Planck equation, which
describes a random walk with VADM-dependent drift and diffusion coefficients.
We demonstrate first that our method is able to retrieve the correct shape of
the drift and diffusion coefficients from a time series generated by a test
model. Analysis of the Sint-2000 data shows that the geomagnetic dipole mode
has a linear growth time of 13 to 33 kyr, and that the nonlinear quenching of
the growth rate follows a quadratic function of the type [1-(x/x0)^2]. On
theoretical grounds, the diffusive motion of the VADM is expected to be driven
by multiplicative noise, and the corresponding diffusion coefficient to scale
quadratically with dipole strength. However, analysis of the Sint-2000 VADM
data reveals a diffusion which depends only very weakly on the dipole strength.
This may indicate that the magnetic field quenches the amplitude of the
turbulent velocity in the Earth's outer core.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:17:30 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Brendel",
"K.",
""
],
[
"Kuipers",
"J.",
""
],
[
"Barkema",
"G. T.",
""
],
[
"Hoyng",
"P.",
""
]
] |
0707.0624 | Andrew Barnes | A. D. Barnes, J. Casares, R. Cornelisse, P. A. Charles, D. Steeghs, R.
I. Hynes, K. O'Brien | Kinematical Studies of the Low Mass X-Ray Binary GR Mus (XB1254-690) | 10 pages, 14 figures, accepted for publication in MNRAS | null | 10.1111/j.1365-2966.2007.12174.x | null | astro-ph | null | We present simultaneous high-resolution optical spectroscopy and X-ray data
of the X-ray binary system GR Mus (XB1254-690), obtained over a full range of
orbital phases. The X-ray observations are used to re-establish the orbital
ephemeris for this source. The optical data includes the first spectroscopic
detection of the donor star in this system, through the use of the Doppler
Tomography technique on the Bowen fluorescence blend (~4630-4650 A). In
combination with an estimate for the orbital parameters of the compact object
using the wings of the He II 4686 emission line, dynamical mass constraints of
1.20 < M_X/M_{sun} < 2.64 for the neutron star and 0.45 < M_2/M_{sun} < 0.85
for the companion are derived.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:21:05 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Barnes",
"A. D.",
""
],
[
"Casares",
"J.",
""
],
[
"Cornelisse",
"R.",
""
],
[
"Charles",
"P. A.",
""
],
[
"Steeghs",
"D.",
""
],
[
"Hynes",
"R. I.",
""
],
[
"O'Brien",
"K.",
""
]
] |
0707.0625 | Oliver Burmeister | A. Bunkowski, O. Burmeister, K. Danzmann, and R. Schnabel | Input-output relations for a 3-port grating coupled Fabry-Perot cavity | null | Optics Letters 30, 1183 (2005) | 10.1364/OL.30.001183 | null | physics.optics | null | We analyze an optical 3-port reflection grating by means of a scattering
matrix formalism. Amplitude and phase relations between the 3 ports, i.e. the 3
orders of diffraction are derived. Such a grating can be used as an
all-reflective, low-loss coupler to Fabry-Perot cavities. We derive the input
output relations of a 3-port grating coupled cavity and find distinct
properties not present in 2-port coupled cavities. The cavity relations further
reveal that the 3-port coupler can be designed such that the additional cavity
port interferes destructively. In this case the all-reflective, low-loss,
single-ended Fabry-Perot cavity becomes equivalent to a standard transmissive,
2-port coupled cavity.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:22:27 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bunkowski",
"A.",
""
],
[
"Burmeister",
"O.",
""
],
[
"Danzmann",
"K.",
""
],
[
"Schnabel",
"R.",
""
]
] |
0707.0626 | Thomas Jarlborg | T. Jarlborg | The importance of thermal disorder and electronic occupation for the
T-dependence of the optical conductivity in FeSi and MnSi | (5 pages, 4 figures) | null | 10.1103/PhysRevB.76.205105 | null | cond-mat.mtrl-sci | null | The spectral weight (SW) for optical transitions in FeSi and MnSi are
calculated as function of temperature by means of LMTO-LDA band calculations.
The main effects, caused by structural disorder and electronic Fermi-Dirac
distribution, act oppositely on the T-dependence of the SW, while the variation
of the magnetic moment in MnSi has only a minor effect. The calculations agree
with the experimental findings of an increasing SW in FeSi and a decreasing SW
in MnSi as function of T. The results can be understood from the change of the
bandstructure with disorder.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:28:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Jarlborg",
"T.",
""
]
] |
0707.0627 | Fuwen Zhang Mr. | Fu-Wen Zhang, Yi-Ping Qin and Bin-Bin Zhang | Dependence of Temporal Properties on Energy in Long-Lag, Wide-Pulse
Gamma-Ray Bursts | 20 pages, 7 figures, added references, matched to published version,
accepted for publication in PASJ | Publ. Astron. Soc. Japan 59 (2007) 857-867 | 10.1093/pasj/59.4.857 | null | astro-ph | null | We employed a sample compiled by Norris et al. (2005, ApJ, 625, 324) to study
the dependence of the pulse temporal properties on energy in long-lag,
wide-pulse gamma-ray bursts. Our analysis shows that the pulse peak time, rise
time scale and decay time scale are power law functions of energy, which is a
preliminary report on the relationships between the three quantities and
energy. The power law indexes associated with the pulse width, rise time scale
and decay time scale are correlated and the correlation between the indexes
associated with the pulse width and the decay time scale is more obvious. In
addition, we have found that the pulse peak lag is strongly correlated with the
CCF lag, but the centroid lag is less correlated with the peak lag and CCF lag.
Based on these results and some previous investigations, we tend to believe
that all energy-dependent pulse temporal properties may come from the joint
contribution of both the hydrodynamic processes of the outflows and the
curvature effect, where the energy-dependent spectral lag may be mainly
dominated by the dynamic process and the energy-dependent pulse width may be
mainly determined by the curvature effect.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:35:26 GMT"
},
{
"version": "v2",
"created": "Fri, 28 Sep 2007 14:54:05 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Zhang",
"Fu-Wen",
""
],
[
"Qin",
"Yi-Ping",
""
],
[
"Zhang",
"Bin-Bin",
""
]
] |
0707.0628 | Genevieve Belanger | C.Hugonie, G.Belanger, A.Pukhov | Dark Matter in a Constrained NMSSM | 17 pages, 6 figures, references added, some comments added, version
to be published in JCAP | JCAP 0711:009,2007 | 10.1088/1475-7516/2007/11/009 | LAPTH-1193/07, LPTA/0729 | hep-ph | null | We explore the parameter space of a Constrained Next-to-Minimal
Supersymmetric Standard Model with GUT scale boundary conditions (CNMSSM) and
find regions where the relic density of the lightest neutralino is compatible
with the WMAP measurement. We emphasize differences with the MSSM: cases where
annihilation of the LSP occurs via a Higgs resonance at low values of tan\beta
and cases where the LSP has a large singlino component. The particle spectrum
as well as theoretical and collider constraints are calculated with NMSSMTools.
All neutralino annihilation and coannihilation processes are then computed with
micrOMEGAs, taking into account higher order corrections to the Higgs sector.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 16:36:05 GMT"
},
{
"version": "v2",
"created": "Sun, 8 Jul 2007 12:52:22 GMT"
},
{
"version": "v3",
"created": "Tue, 16 Oct 2007 08:53:08 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Hugonie",
"C.",
""
],
[
"Belanger",
"G.",
""
],
[
"Pukhov",
"A.",
""
]
] |
0707.0629 | Attila Szallas | Anuradha Jagannathan, Attila Szallas, Stefan Wessel, Michel Duneau | Penrose Quantum Antiferromagnet | 4 pages, 5 figures | Phys. Rev. B 75, 212407 (2007) | 10.1103/PhysRevB.75.212407 | null | cond-mat.str-el | null | The Penrose tiling is a perfectly ordered two dimensional structure with
fivefold symmetry and scale invariance under site decimation. Quantum spin
models on such a system can be expected to differ significantly from more
conventional structures as a result of its special symmetries. In one
dimension, for example, aperiodicity can result in distinctive quantum
entanglement properties. In this work, we study ground state properties of the
spin-1/2 Heisenberg antiferromagnet on the Penrose tiling, a model that could
also be pertinent for certain three dimensional antiferromagnetic
quasicrystals. We show, using spin wave theory and quantum Monte Carlo
simulation, that the local staggered magnetizations strongly depend on the
local coordination number z and are minimized on some sites of five-fold
symmetry. We present a simple explanation for this behavior in terms of
Heisenberg stars. Finally we show how best to represent this complex
inhomogeneous ground state, using the "perpendicular space" representation of
the tiling.
| [
{
"version": "v1",
"created": "Wed, 4 Jul 2007 14:36:54 GMT"
},
{
"version": "v2",
"created": "Fri, 16 Nov 2007 23:10:23 GMT"
}
] | 2011-11-10T00:00:00 | [
[
"Jagannathan",
"Anuradha",
""
],
[
"Szallas",
"Attila",
""
],
[
"Wessel",
"Stefan",
""
],
[
"Duneau",
"Michel",
""
]
] |
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