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| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0708.1349 | Anwar Hasmy | A. Hasmy, L. Rincon, R. Hernandez, V. Mujica, M. Marquez and C.
Gonzalez | On the formation and the stability of suspended transition metal
monatomic chains | null | null | null | null | cond-mat.mtrl-sci | null | We present a Tight-Binding Molecular Dynamics investigation of the stability,
the geometrical and the electronic structure of suspended monatomic transition
metal chains. We show that linear and stable monatomic chains are formed at
temperature equal or smaller than 500 K for Au, 200 K for Ag and 4 K for Cu. We
also evidence that such stability is associated with the persisting sd orbital
hybridization along the chains. The study highlight fundamental limitations of
conductance measurement experiments to detect these chains in the breaking
process of nanowires.
| [
{
"version": "v1",
"created": "Thu, 9 Aug 2007 22:47:48 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Hasmy",
"A.",
""
],
[
"Rincon",
"L.",
""
],
[
"Hernandez",
"R.",
""
],
[
"Mujica",
"V.",
""
],
[
"Marquez",
"M.",
""
],
[
"Gonzalez",
"C.",
""
]
] |
0708.1350 | Timothy Wallstrom | Timothy C. Wallstrom | The marginalization paradox and the formal Bayes' law | Presented at Maxent 2007, Saratoga Springs, NY, July 2007 | null | 10.1063/1.2821304 | LANL technical report, LAUR 07-4666 | math.ST math.PR stat.TH | null | It has recently been shown that the marginalization paradox (MP) can be
resolved by interpreting improper inferences as probability limits. The key to
the resolution is that probability limits need not satisfy the formal Bayes'
law, which is used in the MP to deduce an inconsistency. In this paper, I
explore the differences between probability limits and the more familiar
pointwise limits, which do imply the formal Bayes' law, and show how these
differences underlie some key differences in the interpretation of the MP.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 06:26:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wallstrom",
"Timothy C.",
""
]
] |
0708.1351 | Anne Pellerin | Anne Pellerin, Carmelle Robert | Physical Properties of Young Stellar Populations in 24 Starburst
Galaxies Observed with FUSE | 24 pages including figures. Accepted for publication in MNRAS | null | 10.1111/j.1365-2966.2007.12250.x | STScI e-print #1772 | astro-ph | null | We presents the main physical properties of very young stellar populations
seen with FUSE in 24 individual starbursts. These characteristics have been
obtained using the evolutionary spectral synthesis technique in the
far-ultraviolet range with the LavalSB code. For each starburst, quantitative
values for age, metallicity, initial mass function slope, stellar mass, and
internal extinction have been obtained and discussed in details. Limits of the
code have been tested. One main conclusion is that most starbursts (and
probably all of them) cannot be represented by any continuous star formation
burst in the far-ultraviolet. Also, quantitative values of various optical
diagnostics related to these stellar populations have been predicted.
Underlying stellar populations, dominated by B-type stars, have been detected
in NGC 1140, NGC 4449, and possibly NGC 3991. We characterized the young
stellar populations of less than 5 Myr in Seyfert 2 nuclei.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 19:55:17 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Pellerin",
"Anne",
""
],
[
"Robert",
"Carmelle",
""
]
] |
0708.1352 | Jonathan Kirby | Jonathan Kirby | The theory of the exponential differential equations of semiabelian
varieties | 53 pages; v3: Substantial changes, including a completely new
introduction | Selecta Mathematica 15, (2009) no. 3, 445--486 | 10.1007/s00029-009-0001-7 | null | math.AG math.LO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The complete first order theories of the exponential differential equations
of semiabelian varieties are given. It is shown that these theories also arises
from an amalgamation-with-predimension construction in the style of Hrushovski.
The theory includes necessary and sufficient conditions for a system of
equations to have a solution. The necessary condition generalizes Ax's
differential fields version of Schanuel's conjecture to semiabelian varieties.
There is a purely algebraic corollary, the "Weak CIT" for semiabelian
varieties, which concerns the intersections of algebraic subgroups with
algebraic varieties.
| [
{
"version": "v1",
"created": "Thu, 9 Aug 2007 23:18:56 GMT"
},
{
"version": "v2",
"created": "Mon, 17 Dec 2007 13:46:39 GMT"
},
{
"version": "v3",
"created": "Tue, 9 Jun 2009 11:24:54 GMT"
}
] | 2009-10-16T00:00:00 | [
[
"Kirby",
"Jonathan",
""
]
] |
0708.1353 | Ken Amos | P. Fraser, K. Amos, S. Karataglidis, L. Canton, G. Pisent, J. P.
Svenne | Non-localities in nucleon-nucleus potentials | 12 pages, 11 figures, submitted to EPJA | Eur.Phys.J.A35:69-80,2008 | 10.1140/epja/i2007-10524-1 | null | nucl-th | null | Two causes of non-locality inherent in nucleon-nucleus scattering are
considered. They are the results of two-nucleon antisymmetry of the projectile
with each nucleon in the nucleus and the dynamic polarization potential
representation of channel coupling. For energies $\sim 40 - 300$ MeV, a
g-folding model of the optical potential is used to show the influence of the
knock-out process that is a result of the two-nucleon antisymmetry. To explore
the dynamic polarization potential caused by channel coupling, a multichannel
algebraic scattering model has been used for low-energy scattering.
| [
{
"version": "v1",
"created": "Thu, 9 Aug 2007 23:44:57 GMT"
}
] | 2008-12-18T00:00:00 | [
[
"Fraser",
"P.",
""
],
[
"Amos",
"K.",
""
],
[
"Karataglidis",
"S.",
""
],
[
"Canton",
"L.",
""
],
[
"Pisent",
"G.",
""
],
[
"Svenne",
"J. P.",
""
]
] |
0708.1354 | Ken Amos | K. Amos, P. Fraser, D. van der Knijff, L. Canton, G. Pisent, S.
Karataglidis, J. P. Svenne | Multi-channel algebraic scattering theory and the structure of exotic
compound nuclei | 8 pages, 4 figures, conference paper to ispun07 Vietnam | null | null | null | nucl-th | null | A Multi-Channel Algebraic Scattering (MCAS) theory is presented with which
the properties of a compound nucleus are found from a coupled-channel problem.
The method defines both the bound states and resonances of the compound
nucleus, even if the compound nucleus is particle unstable. All resonances of
the system are found no matter how weak and/or narrow. Spectra of mass-7 nuclei
and of {}^{15}F, and MCAS results for a radiative capture cross section are
presented.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 00:11:11 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Amos",
"K.",
""
],
[
"Fraser",
"P.",
""
],
[
"van der Knijff",
"D.",
""
],
[
"Canton",
"L.",
""
],
[
"Pisent",
"G.",
""
],
[
"Karataglidis",
"S.",
""
],
[
"Svenne",
"J. P.",
""
]
] |
0708.1355 | Herman Julio Mosquera Cuesta | Herman J. Mosquera Cuesta, Habib Dumet M. and Cristina Furlanetto | Confronting the Hubble Diagram of Gamma-Ray Bursts with Cardassian
Cosmology | Revtex4 format, 17 pages, 13 figures, 5 tables | JCAP 0807:004,2008 | 10.1088/1475-7516/2008/07/004 | null | astro-ph gr-qc hep-ex hep-th | null | We construct the Hubble diagram (HD) of Gamma-Ray Bursts (GRBs) with
redshifts reaching up to $z \sim 6$, by using five luminosity vs. luminosity
indicator relations calibrated with the Cardassian cosmology. This model has a
major interesting feature: despite of being matter-dominated and flat, it can
explain the present accelerate expansion of the universe. This is the first
study of this class of models using high redshift GRBs. We have performed a
$\chi$-square statistical analysis of the GRBs calibrated with the Cardassian
model, and also combined them with both the current Cosmic Microwave Background
and Baryonic Acoustic Oscillation data. Our results show consistency between
the current observational data and the model predictions. In particular, the
best-fit parameters obtained from the $\chi^2$-analysis are in agreement with
those obtained from the Concordance Cosmology ($\Lambda$-CDM). We determine the
redshift at which the universe would start to follow the Cardassian expansion,
i. e., \zc, and both the redshift at which the universe had started to
accelerate, i. e., \zac, and the age-redshift relation $H_0t_0$. Our results
also show that the universe, from the point of view of GRBs, had undergo a
transition to acceleration at a redshift $z \approx 0.2-0.7$, which agrees with
the SNIa results. Hence, after confronting the Cardassian scenario with the
GRBs HD and proving its consistency with it, we conclude that GRBs should
indeed be considered a complementary tool to several other astronomical
observations for studies of high accuracy in cosmology.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 18:00:59 GMT"
}
] | 2011-05-24T00:00:00 | [
[
"Cuesta",
"Herman J. Mosquera",
""
],
[
"M.",
"Habib Dumet",
""
],
[
"Furlanetto",
"Cristina",
""
]
] |
0708.1356 | Re-Bing Wu | Rebing Wu, Herschel Rabitz, Michael Hsieh | Characterization of the Critical Submanifolds in Quantum Ensemble
Control Landscapes | 13 pages. submitted to Journal of Physics A | null | 10.1088/1751-8113/41/1/015006 | null | quant-ph | null | A quantum control landscape is defined as the physical objective as a
function of the control variables to be optimized. Analyzing the topology of
these landscapes is important for understanding the origins of the increasing
number of laboratory successes in the optimal control of quantum processes.
This paper proposes a simple scheme to compute the characteristics of the
critical topology of the quantum ensemble control landscapes for observables,
showing that the set of disjoint critical submanifolds one-to-one corresponds
to a finite number of contingency tables that solely depend on the degeneracy
structure of the eigenvalues of the initial system density matrix and the
observable to be controlled. The landscape characteristics can be calculated as
functions of the table entries, including the dimensions and the numbers of
positive and negative eigenvalues of the Hessian quadratic form of each of the
connected components of the critical submanifolds. Typical examples are given
to illustrate the effectiveness of this method.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 01:41:27 GMT"
},
{
"version": "v2",
"created": "Wed, 19 Mar 2008 17:05:55 GMT"
}
] | 2013-04-01T00:00:00 | [
[
"Wu",
"Rebing",
""
],
[
"Rabitz",
"Herschel",
""
],
[
"Hsieh",
"Michael",
""
]
] |
0708.1357 | Toufik Mansour Dr. | Mark Dukes, Vit Jel\'inek, Toufik Mansour, and Astrid Reifegerste | New equivalences for pattern avoiding involutions | 11 pages, 2 Tables | null | null | null | math.CO | null | We complete the Wilf classification of signed patterns of length 5 for both
signed permutations and signed involutions. New general equivalences of
patterns are given which prove Jaggard's conjectures concerning involutions in
the symmetric group avoiding certain patterns of length 5 and 6. In this way,
we also complete the Wilf classification of S_5, S_6, and S_7 for both
permutations and involutions.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 01:36:19 GMT"
},
{
"version": "v2",
"created": "Thu, 16 Aug 2007 14:42:33 GMT"
},
{
"version": "v3",
"created": "Tue, 22 Jan 2008 18:55:18 GMT"
}
] | 2008-01-22T00:00:00 | [
[
"Dukes",
"Mark",
""
],
[
"Jelínek",
"Vit",
""
],
[
"Mansour",
"Toufik",
""
],
[
"Reifegerste",
"Astrid",
""
]
] |
0708.1358 | Chul Kim | Chul Kim, S. R. Park, C. S. Leem, D. J. Song, H. U. Jin, H.-D. Kim, F.
Ronning, C. Kim | Electron Removal Self Energy and its application to Ca2CuO2Cl2 | 5 pages, 3 figures | Physical Review B 76, 104505 (2007) | 10.1103/PhysRevB.76.104505 | null | cond-mat.supr-con cond-mat.str-el | null | We propose using the self energy defined for the electron removal Green's
function. Starting from the electron removal Green's function, we obtained
expressions for the removal self energy Sigma^ER (k,omega) that are applicable
for non-quasiparticle photoemission spectral functions from a single band
system. Our method does not assume momentum independence and produces the self
energy in the full k-omega space. The method is applied to the angle resolved
photoemission from Ca_2CuO_2Cl_2 and the result is found to be compatible with
the self energy value from the peak width of sharp features. The self energy is
found to be only weakly k-dependent. In addition, the Im Sigma shows a maximum
at around 1 eV where the high energy kink is located.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 02:04:29 GMT"
}
] | 2009-09-29T00:00:00 | [
[
"Kim",
"Chul",
""
],
[
"Park",
"S. R.",
""
],
[
"Leem",
"C. S.",
""
],
[
"Song",
"D. J.",
""
],
[
"Jin",
"H. U.",
""
],
[
"Kim",
"H. -D.",
""
],
[
"Ronning",
"F.",
""
],
[
"Kim",
"C.",
""
]
] |
0708.1359 | Sang-Koog Kim | Konstantin Yu. Guslienko, Ki-Suk Lee, and Sang-Koog Kim | Dynamic Origin of Vortex Core Switching in Soft Magnetic Nanodots | 17 pages and 3 figures | Phys. Rev. Lett. 100, 027203 (2008) | 10.1103/PhysRevLett.100.027203 | null | cond-mat.mtrl-sci | null | The magnetic vortex with the in-plane curling magnetization and the
out-of-plane magnetization at the core is a unique ground state in nanoscale
magnetic elements. This kind of magnetic vortex can be used as a memory unit
for information storage, through its downward or upward core-orientation and,
thus, controllable core switching deserves some special attention. Our
analytical and micromagnetic calculations reveal that the origin of the vortex
core reversal is a gyrotropic field. This field is induced by vortex dynamic
motion and is proportional to the velocity of the moving vortex. Our
calculations elucidate the physical origin of the vortex core dynamic reversal
and offer a key to effective manipulation of the vortex-core orientation.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 02:04:43 GMT"
}
] | 2010-02-03T00:00:00 | [
[
"Guslienko",
"Konstantin Yu.",
""
],
[
"Lee",
"Ki-Suk",
""
],
[
"Kim",
"Sang-Koog",
""
]
] |
0708.1360 | Yoji Kawamura | Yoji Kawamura | Hole Structures in Nonlocally Coupled Noisy Phase Oscillators | 4 pages, 4 figures, to appear in Phys. Rev. E | Phys. Rev. E 76, 047201 (2007) | 10.1103/PhysRevE.76.047201 | null | nlin.PS | null | We demonstrate that a system of nonlocally coupled noisy phase oscillators
can collectively exhibit a hole structure, which manifests itself in the
spatial phase distribution of the oscillators. The phase model is described by
a nonlinear Fokker-Planck equation, which can be reduced to the complex
Ginzburg-Landau equation near the Hopf bifurcation point of the uniform
solution. By numerical simulations, we show that the hole structure clearly
appears in the space-dependent order parameter, which corresponds to the
Nozaki-Bekki hole solution of the complex Ginzburg-Landau equation.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 02:14:34 GMT"
}
] | 2007-10-03T00:00:00 | [
[
"Kawamura",
"Yoji",
""
]
] |
0708.1361 | Sumiyoshi Abe | Yuichi Itto (1) and Sumiyoshi Abe (1)(2)((1)Mie University,
Japan,(2)Institut Superieur des Materiaux et Mecaniques Avances, Le Mans,
France) | Stationary photon-atom entanglement and flow equation | 21 pages, no figures | null | 10.1016/j.physa.2007.10.005 | null | quant-ph cond-mat.other | null | Stationary photon-atom entanglement is discussed by applying the method of
flow equation to the Jaynes-Cummings model. A nonlocal continuous unitary
transformation is explicitly constructed and the associated positive
operator-valued measures for the photons and atom are obtained. Then, flow of
the entanglement entropy is analyzed. A comment is also made on implementing
the unitary operation in the method of flow equation. This method may offer a
new strategy for quantum-state engineering.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 02:32:11 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Itto",
"Yuichi",
""
],
[
"Abe",
"Sumiyoshi",
""
]
] |
0708.1362 | David Wolpert | David H. Wolpert | Physical limits of inference | 43 pages, updated version of Physica D version, which originally
appeared in 2007 CNLS conference on unconventional computation | PhysicaD237:1257-1281,2008 | 10.1016/j.physd.2008.03.040 | null | cond-mat.stat-mech cs.CC cs.IT gr-qc math.IT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I show that physical devices that perform observation, prediction, or
recollection share an underlying mathematical structure. I call devices with
that structure "inference devices". I present a set of existence and
impossibility results concerning inference devices. These results hold
independent of the precise physical laws governing our universe. In a limited
sense, the impossibility results establish that Laplace was wrong to claim that
even in a classical, non-chaotic universe the future can be unerringly
predicted, given sufficient knowledge of the present. Alternatively, these
impossibility results can be viewed as a non-quantum mechanical "uncertainty
principle". Next I explore the close connections between the mathematics of
inference devices and of Turing Machines. In particular, the impossibility
results for inference devices are similar to the Halting theorem for TM's.
Furthermore, one can define an analog of Universal TM's (UTM's) for inference
devices. I call those analogs "strong inference devices". I use strong
inference devices to define the "inference complexity" of an inference task,
which is the analog of the Kolmogorov complexity of computing a string. However
no universe can contain more than one strong inference device. So whereas the
Kolmogorov complexity of a string is arbitrary up to specification of the UTM,
there is no such arbitrariness in the inference complexity of an inference
task. I end by discussing the philosophical implications of these results,
e.g., for whether the universe "is" a computer.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 03:19:38 GMT"
},
{
"version": "v2",
"created": "Thu, 23 Oct 2008 22:11:34 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Wolpert",
"David H.",
""
]
] |
0708.1363 | Monica Nevins | Monica Nevins | On Rational Nilpotent Orbits of $SL_{n}$ and $Sp_{2n}$ over a Local
Non-Archimedean Field | v2, 27 pages. Reduced to single-spacing (from double-spaced first
version of 35 pages); typos corrected in Section 2; Corollary 4.5
strengthened | null | null | null | math.RT | null | We relate the partition-type parametrization of rational (arithmetic)
nilpotent adjoint orbits of the split classical groups $SL_n$ and $Sp_{2n}$
over local non-Archimedean fields with a parametrization, introduced by
DeBacker in 2002, which uses the associated Bruhat-Tits building to relate the
question to one over the residue field.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 04:12:28 GMT"
},
{
"version": "v2",
"created": "Tue, 15 Jan 2008 17:14:05 GMT"
}
] | 2008-01-15T00:00:00 | [
[
"Nevins",
"Monica",
""
]
] |
0708.1364 | Christopher Stubbs | Christopher W. Stubbs, F. William High, Matthew R. George, Kimberly L.
DeRose, and Stephane Blondin, John L. Tonry, Kenneth C. Chambers, Benjamin R.
Granett, David L. Burke, and R. Chris Smith | Towards More Precise Survey Photometry for PanSTARRS and LSST: Measuring
Directly the Optical Transmission Spectrum of the Atmosphere | 41 pages, 14 figures. Accepted PASP | Publ.Astron.Soc.Pac.119:1163-1178,2007 | 10.1086/522208 | null | astro-ph | null | Motivated by the recognition that variation in the optical transmission of
the atmosphere is probably the main limitation to the precision of ground-based
CCD measurements of celestial fluxes, we review the physical processes that
attenuate the passage of light through the Earth's atmosphere. The next
generation of astronomical surveys, such as PanSTARRS and LSST, will greatly
benefit from dedicated apparatus to obtain atmospheric transmission data that
can be associated with each survey image. We review and compare various
approaches to this measurement problem, including photometry, spectroscopy, and
LIDAR. In conjunction with careful measurements of instrumental throughput,
atmospheric transmission measurements should allow next-generation imaging
surveys to produce photometry of unprecedented precision. Our primary concerns
are the real-time determination of aerosol scattering and absorption by water
along the line of sight, both of which can vary over the course of a night's
observations.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 04:43:57 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Stubbs",
"Christopher W.",
""
],
[
"High",
"F. William",
""
],
[
"George",
"Matthew R.",
""
],
[
"DeRose",
"Kimberly L.",
""
],
[
"Blondin",
"Stephane",
""
],
[
"Tonry",
"John L.",
""
],
[
"Chambers",
"Kenneth C.",
""
],
[
"Granett",
"Benjamin R.",
""
],
[
"Burke",
"David L.",
""
],
[
"Smith",
"R. Chris",
""
]
] |
0708.1365 | Chin-Fei Lee | Chin-Fei Lee, Paul T.P. Ho, Aina Palau, Naomi Hirano, Tyler L. Bourke,
Hsien Shang and Qizhou Zhang | Submillimeter arcsecond-resolution mapping of the highly collimated
protostellar jet HH 211 | 24 pages, 11 figures | null | 10.1086/522333 | null | astro-ph | null | We have mapped the protostellar jet HH 211 in 342 GHz continuum, SiO
($J=8-7$), and CO ($J=3-2$) emission at $\sim$ \arcs{1} resolution with the
Submillimeter Array (SMA). Thermal dust emission is seen in continuum at the
center of the jet, tracing an envelope and a possible optically thick compact
disk (with a size $<$ 130 AU) around the protostar. A knotty jet is seen in CO
and SiO as in \H2{}, but extending closer to the protostar. It consists of a
chain of knots on each side of the protostar, with an interknot spacing of
$\sim$ \arcs{2}$-$\arcs{3} or 600$-$900 AU and the innermost pair of knots at
only $\sim$ \arcsa{1}{7} or 535 AU from the protostar. These knots likely trace
unresolved internal (bow) shocks (i.e., working surfaces) in the jet, with a
velocity range up to $\sim$ 25 \vkm{}. The two-sided mass-loss rate of the jet
is estimated to be $\sim (0.7-2.8)\times 10^{-6}$ \solarmass{} yr$^{-1}$. The
jet is episodic, precessing, and bending. A velocity gradient is seen
consistently across two bright SiO knots (BK3 and RK2) perpendicular to the jet
axis, with $\sim$ 1.5$\pm$0.8 \vkm{} at $\sim$ 30$\pm$15 AU, suggesting a
presence of a jet rotation. The launching radius of the jet, derived from the
potential jet rotation, is $\sim$ 0.15$-$0.06 AU in the inner disk.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 04:57:21 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Lee",
"Chin-Fei",
""
],
[
"Ho",
"Paul T. P.",
""
],
[
"Palau",
"Aina",
""
],
[
"Hirano",
"Naomi",
""
],
[
"Bourke",
"Tyler L.",
""
],
[
"Shang",
"Hsien",
""
],
[
"Zhang",
"Qizhou",
""
]
] |
0708.1366 | Hyun C. Lee | S.-R. Eric Yang and Hyun C. Lee | X-ray edge problem of graphene | 7 pages, 1 figure | Physical Review B, Vol. 76, 245411 (2007). | 10.1103/PhysRevB.76.245411 | null | cond-mat.str-el | null | The X-ray edge problem of graphene with the Dirac fermion spectrum is
studied. At half-filling the linear density of states suppresses the singular
response of the Fermi liquid, while away from half-filling the singular
features of the Fermi liquid reappear. The crossover behavior as a function of
the Fermi energy is examined in detail. The exponent of the power-law
absorption rate depends both on the intra- and inter-valley scattering, and it
changes as a function of the Fermi energy, which may be tested experimentally.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 05:29:12 GMT"
},
{
"version": "v2",
"created": "Wed, 14 Nov 2007 03:08:41 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Yang",
"S. -R. Eric",
""
],
[
"Lee",
"Hyun C.",
""
]
] |
0708.1367 | Atsushi Taruya | Atsushi Taruya, Takashi Hiramatsu | A Closure Theory for Non-linear Evolution of Cosmological Power Spectra | 22 pages, 4 figures, accepted for publication in ApJ | null | 10.1086/526515 | null | astro-ph | null | We apply a non-linear statistical method in turbulence to the cosmological
perturbation theory and derive a closed set of evolution equations for matter
power spectra. The resultant closure equations consistently recover the
one-loop results of standard perturbation theory and beyond that, it is still
capable of treating the non-linear evolution of matter power spectra. We find
the exact integral expressions for the solutions of closure equations. These
analytic expressions coincide with the renormalized one-loop results presented
by Crocce & Scoccimarro (2006,2007). By constructing the non-linear propagator,
we analytically evaluate the non-linear matter power spectra based on the
first-order Born approximation of the integral expressions and compare it with
those of the renormalized perturbation theory.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 05:46:38 GMT"
},
{
"version": "v2",
"created": "Wed, 14 Nov 2007 11:49:53 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Taruya",
"Atsushi",
""
],
[
"Hiramatsu",
"Takashi",
""
]
] |
0708.1368 | Takeshi Oota | Tsuyoshi Houri, Takeshi Oota and Yukinori Yasui | Closed conformal Killing-Yano tensor and Kerr-NUT-de Sitter spacetime
uniqueness | 7 pages, LaTeX | Phys.Lett.B656:214-216,2007 | 10.1016/j.physletb.2007.09.034 | OCU-PHYS 273 | hep-th | null | We study spacetimes with a closed conformal Killing-Yano tensor. It is shown
that the D-dimensional Kerr-NUT-de Sitter spacetime constructed by Chen-Lu-Pope
is the only spacetime admitting a rank-2 closed conformal Killing-Yano tensor
with a certain symmetry.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 05:47:50 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Houri",
"Tsuyoshi",
""
],
[
"Oota",
"Takeshi",
""
],
[
"Yasui",
"Yukinori",
""
]
] |
0708.1369 | Seong-Gon Kim | J. Houze, Sungho Kim, Seong-Jin Park, Randall M. German, M. F.
Horstemeyer, and Seong-Gon Kim | The effect of Fe atoms on the adsorption of a W atom on W(100) surface | 9 pages, 2 figures | null | 10.1063/1.2924411 | null | cond-mat.mtrl-sci | null | We report a first-principles calculation that models the effect of iron (Fe)
atoms on the adsorption of a tungsten (W) atom on W(100) surfaces. The
adsorption of a W atom on a clean W(100) surface is compared with that of a W
atom on a W(100) surface covered with a monolayer of Fe atoms. The total energy
of the system is computed as the function of the height of the W adatom. Our
result shows that the W atom first adsorbs on top of the Fe monolayer. Then the
W atom can replace one of the Fe atoms through a path with a moderate energy
barrier and reduce its energy further. This intermediate site makes the
adsorption (and desorption) of W atoms a two-step process in the presence of Fe
atoms and lowers the overall adsorption energy by nearly 2.4 eV. The Fe atoms
also provide a surface for W atoms to adsorb facilitating the diffusion of W
atoms. The combination of these two effects result in a much more efficient
desorption and diffusion of W atoms in the presence of Fe atoms. Our result
provides a fundamental mechanism that can explain the activated sintering of
tungsten by Fe atoms.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 05:58:29 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Houze",
"J.",
""
],
[
"Kim",
"Sungho",
""
],
[
"Park",
"Seong-Jin",
""
],
[
"German",
"Randall M.",
""
],
[
"Horstemeyer",
"M. F.",
""
],
[
"Kim",
"Seong-Gon",
""
]
] |
0708.1370 | Kohta Murase | Kohta Murase, Kunihito Ioka | Closure Relations for Electron-Positron Pair-Signatures in Gamma-Ray
Bursts | 7 pages, 4 figures, accepted for publication in ApJ, with extended
discussions. Conclusions unchanged | Astrophys.J. 676 (2008) 1123 | 10.1086/527667 | YITP-08-103, KEK-TH-1403, KEK-Cosmo-13 | astro-ph | null | We present recipes to diagnose the fireball of gamma-ray bursts (GRBs) by
combining observations of electron-positron pair-signatures (the
pair-annihilation line and the cutoff energy due to the pair-creation process).
Our recipes are largely model-independent and extract information even from the
non-detection of either pair-signature. We evaluate physical quantities such as
the Lorentz factor, optical depth and pair-to-baryon ratio, only from the
observable quantities. In particular, we can test whether the prompt emission
of GRBs comes from the pair/baryonic photosphere or not. The future-coming
Gamma-Ray Large Area Space Telescope (GLAST) satellite will provide us with
good chances to use our recipes by detecting or non-detecting pair-signatures.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:20:38 GMT"
},
{
"version": "v2",
"created": "Mon, 3 Dec 2007 18:47:37 GMT"
}
] | 2015-04-23T00:00:00 | [
[
"Murase",
"Kohta",
""
],
[
"Ioka",
"Kunihito",
""
]
] |
0708.1371 | Masao Yano | M. Yano, A. Sekiyama, H. Fujiwara, Y. Amano, S. Imada, T. Muro, M.
Yabashi, K. Tamasaku, A. Higashiya, T. Ishikawa, Y. Onuki, and S. Suga | Electronic structures of CeRu$_2X_2$ ($X$ = Si, Ge) in the paramagnetic
phase studied by soft X-ray ARPES and hard X-ray photoelectron spectroscopy | 8figures | null | 10.1103/PhysRevB.77.035118 | null | cond-mat.str-el cond-mat.mtrl-sci | null | Soft and hard X-ray photoelectron spectroscopy (PES) has been performed for
one of the heavy fermion system CeRu$_2$Si$_2$ and a $4f$-localized ferromagnet
CeRu$_2$Ge$_2$ in the paramagnetic phase. The three-dimensional band structures
and Fermi surface (FS) shapes of CeRu$_2$Si$_2$ have been determined by soft
X-ray $h\nu$-dependent angle resolved photoelectron spectroscopy (ARPES). The
differences in the Fermi surface topology and the non-$4f$ electronic
structures between CeRu$_2$Si$_2$ and CeRu$_2$Ge$_2$ are qualitatively
explained by the band-structure calculation for both $4f$ itinerant and
localized models, respectively. The Ce valences in CeRu$_2X_2$ ($X$ = Si, Ge)
at 20 K are quantitatively estimated by the single impurity Anderson model
calculation, where the Ce 3d hard X-ray core-level PES and Ce 3d X-ray
absorption spectra have shown stronger hybridization and signature for the
partial $4f$ contribution to the conduction electrons in CeRu$_2$Si$_2$.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 07:34:45 GMT"
},
{
"version": "v2",
"created": "Fri, 14 Dec 2007 10:41:45 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Yano",
"M.",
""
],
[
"Sekiyama",
"A.",
""
],
[
"Fujiwara",
"H.",
""
],
[
"Amano",
"Y.",
""
],
[
"Imada",
"S.",
""
],
[
"Muro",
"T.",
""
],
[
"Yabashi",
"M.",
""
],
[
"Tamasaku",
"K.",
""
],
[
"Higashiya",
"A.",
""
],
[
"Ishikawa",
"T.",
""
],
[
"Onuki",
"Y.",
""
],
[
"Suga",
"S.",
""
]
] |
0708.1372 | Maarten Solleveld | Eric Opdam and Maarten Solleveld | Homological algebra for affine Hecke algebras | 54 pages | Advances in Mathematics 220 (2009), 1549-1601 | null | null | math.RT | null | In this paper we study homological properties of modules over an affine Hecke
algebra H. In particular we prove a comparison result for higher extensions of
tempered modules when passing to the Schwartz algebra S, a certain topological
completion of the affine Hecke algebra. The proof is self-contained and based
on a direct construction of a bounded contraction of certain standard
resolutions of H-modules.
This construction applies for all positive parameters of the affine Hecke
algebra. This is an important feature since it is an ingredient to analyse how
the irreducible discrete series representations of H arise in generic families
over the parameter space of H. For irreducible non-simply laced affine Hecke
algebras this will enable us to give a complete classification of the discrete
series characters for all positive parameters (we will report on this
application in a separate article).
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:24:54 GMT"
}
] | 2009-05-20T00:00:00 | [
[
"Opdam",
"Eric",
""
],
[
"Solleveld",
"Maarten",
""
]
] |
0708.1373 | Philipp Schmidt-Wellenburg | P. Schmidt-Wellenburg, P. Geltenbort, V.V. Nesvizhevsky, C. Plonka, T.
Soldner, F. Vezzu, O. Zimmer | A source of ultra-cold neutrons for the gravitational spectrometer
GRANIT | ISINN 15 conference proceeding Article has been replaced due to minor
orthographic changes | null | null | null | nucl-ex | null | We present the status of the development of a dedicated high density
ultra-cold neutron (UCN) source dedicated to the gravitational spectrometer
GRANIT. The source employs superthermal conversion of cold neutrons to UCN in
superfluid helium. Tests have shown that UCN produced inside the liquid can be
extracted into vacuum. Furthermore a dedicated neutron selection channel was
tested to maintain high initial density and extract only neutrons with a
vertical velocity component 20 cm/s for the spectrometer. This new source would
have a phase-space density of 0.18 cm-3(m/s)-3 for the spectrometer.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 07:57:00 GMT"
},
{
"version": "v2",
"created": "Tue, 21 Aug 2007 13:47:49 GMT"
}
] | 2007-08-21T00:00:00 | [
[
"Schmidt-Wellenburg",
"P.",
""
],
[
"Geltenbort",
"P.",
""
],
[
"Nesvizhevsky",
"V. V.",
""
],
[
"Plonka",
"C.",
""
],
[
"Soldner",
"T.",
""
],
[
"Vezzu",
"F.",
""
],
[
"Zimmer",
"O.",
""
]
] |
0708.1374 | Georgi Ganchev | Georgi Ganchev, Nikolai Nikolov | Isogonal Conjugacy and Fermat Problems | 11 pages, 8 figures | null | null | null | math.GM | null | We consider three types of isogonal conjugacy of two points with respect to a
given triangle and characterize any of these types by a geometric equality. As
an application to the Fermat problem with positive weights, we prove that in
the general case the given weights determine uniquely a point X and the
solution to the Fermat problem is the point Y, which is isogonally conjugate of
type I to the point X. We obtain a similar characterization of the solution to
the Fermat problem in the case of mixed weights as well.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:03:02 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Ganchev",
"Georgi",
""
],
[
"Nikolov",
"Nikolai",
""
]
] |
0708.1375 | Igor Karnaukhov | Igor N. Karnaukhov | Luttinger Liquid State with Effective Attractive Hare-Core Interaction | 4 pages, 5 figures | null | null | null | cond-mat.str-el | null | An exact solvable 'zig-zag' ladder model of degenerated spinless fermions is
proposed and solved exactly by the means of the Bethe ansatz. An effective
attractive hard-core interaction and direct Coulomb repulsion of fermions on
the nearest-neighbor sites of different chains induce a new phase state of the
ladder. We give a detailed analysis of the exact phase diagram at zero
temperature, that is characterized by two phases at the filling exceeding 2/3:
itinerant and 'frozen' fermions, for which two different species reside in
spatially separate regions. The critical exponents describing asymptotic
behavior of the correlation functions are calculated using the Bethe ansatz and
conformal field theory. It is shown also, that the density of the magnetization
of the corresponding zig-zag spin-1/2 ladder has a jump equal to 1/3 at the
magnetic field equal to zero.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:21:41 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Karnaukhov",
"Igor N.",
""
]
] |
0708.1376 | Shaun Cole | Shaun Cole, John Helly, Carlos S. Frenk, Hannah Parkinson | The statistical properties of LCDM halo formation | Replaced to match MNRAS accepted version | null | 10.1111/j.1365-2966.2007.12516.x | null | astro-ph | null | We present a comparison of the statistical properties of dark matter halo
merger trees extracted from the Millennium Simulation with Extended
Press-Schechter (EPS) formalism and the related GALFORM Monte-Carlo method for
generating ensembles of merger trees. The volume, mass resolution and output
frequency make the Millennium Simulation a unique resource for the study of the
hierarchical growth of structure. We construct the merger trees of present day
friends-of-friends groups and calculate a variety of statistics that quantify
the masses of their progenitors as a function of redshift; accretion rates; and
the redshift distribution of their most recent major merger. We also look in
the forward direction and quantify the present day mass distribution of halos
into which high redshift progenitors of a specific mass become incorporated. We
find that EPS formalism and its Monte-Carlo extension capture the qualitative
behaviour of all these statistics but, as redshift increases they
systematically underestimate the masses of the most massive progenitors. This
shortcoming is worst for the Monte-Carlo algorithm. We present a fitting
function to a scaled version of the progenitor mass distribution and show how
it can be used to make more accurate predictions of both progenitor and final
halo mass distributions.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:24:01 GMT"
},
{
"version": "v2",
"created": "Wed, 26 Sep 2007 16:04:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cole",
"Shaun",
""
],
[
"Helly",
"John",
""
],
[
"Frenk",
"Carlos S.",
""
],
[
"Parkinson",
"Hannah",
""
]
] |
0708.1377 | Johan Bijnens | Johan Bijnens (Lund) | Quark Mass dependence at Two Loops for Meson Properties | 15 pages, plenary talk at T he XXV International Symposium on Lattice
Field Theory, July 30 - August 4 2007, Regensburg, Germany. v2: some
clarifying statements added | PoSLAT2007:004,2007 | null | LU TP 07-22 | hep-lat hep-ph | null | This talks contains a short introduction to Chiral Perturbation Theory and
the existing calculations to two-loop order in the mesonic sector. I include a
discussion on which quantities the expansion can be organized in. The present
best values of the Low-Energy-Constants as determined from continuum physics
are given as well as the assumptions underlying the fits to experimental data.
I present plots of masses, decay constants and $f_+(0)$ in $K_{\ell3}$ as a
function of quark or meson masses. The talk ends with a list of things for
which it would be extremely useful to have good results from lattice QCD
calculations.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:50:21 GMT"
},
{
"version": "v2",
"created": "Tue, 28 Aug 2007 09:38:26 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bijnens",
"Johan",
"",
"Lund"
]
] |
0708.1378 | Vernet Joel | Robert Fosbury, Carlos De Breuck, Vincenzo Mainieri, Gordon Robertson
and Joel Vernet | Report on the ESO Workshop "Obscured AGN Across Cosmic Time" held at
Kloster Seeon, Bavaria, 5 to 8 June 2007 | To appear in the ESO Messenger, Sep 2007 | null | null | null | astro-ph | null | While the radio-loud, obscured quasars (the radio galaxies) have been known
and studied for decades, new and sensitive X-ray and mid-infrared surveys are
now beginning to reveal large numbers of their radio-quiet counterparts beyond
the local Universe. Consequently, we are approaching the compilation of a
relatively complete census of AGN of all types coving a large fraction of
cosmic time. This is revealing a remarkably intimate connection between the
supermassive black hole and its host galaxy. The workshop reported here was
designed to explore the results of these rapid observational developments and
the nature of the relationships between the stellar and AGN components.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:24:37 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Fosbury",
"Robert",
""
],
[
"De Breuck",
"Carlos",
""
],
[
"Mainieri",
"Vincenzo",
""
],
[
"Robertson",
"Gordon",
""
],
[
"Vernet",
"Joel",
""
]
] |
0708.1379 | Sachindeo Vaidya | A. P. Balachandran, A. Pinzul, B. A. Qureshi and S. Vaidya | S-Matrix on the Moyal Plane: Locality versus Lorentz Invariance | 15 pages, LaTeX, 1 figure | Phys.Rev.D77:025020,2008 | 10.1103/PhysRevD.77.025020 | SU-4252-861, IISc/CHEP/12/07 | hep-th gr-qc hep-ph math-ph math.MP math.QA | null | Twisted quantum field theories on the Groenewold-Moyal plane are known to be
non-local. Despite this non-locality, it is possible to define a generalized
notion of causality. We show that interacting quantum field theories that
involve only couplings between matter fields, or between matter fields and
minimally coupled U(1) gauge fields are causal in this sense. On the other
hand, interactions between matter fields and non-abelian gauge fields violate
this generalized causality. We derive the modified Feynman rules emergent from
these features. They imply that interactions of matter with non-abelian gauge
fields are not Lorentz- and CPT-invariant.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:25:57 GMT"
},
{
"version": "v2",
"created": "Thu, 16 Aug 2007 04:18:27 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Balachandran",
"A. P.",
""
],
[
"Pinzul",
"A.",
""
],
[
"Qureshi",
"B. A.",
""
],
[
"Vaidya",
"S.",
""
]
] |
0708.1380 | Andrea Messina | Andrea Messina (for the CDF Collaboration) | Measurement of the W + Jet Cross Section at CDF | 3 pages, Presented at the XXXVI international Symposium on
Multiparticle Dynamics (ISMD 2006), Rio De Janeiro, Brazil, 2-8 Sept 2006 | Braz.J.Phys.37:840-842,2007 | 10.1590/S0103-97332007000500043 | null | hep-ex | null | A measurement of W->e nu + n-jet cross sections in ppbar collisions at
sqrt(s)=1.96 TeV using the Collider Detector at Fermilab in Run II is
presented. The measurement is based on an integrated luminosity of 320 pb-1,
and includes events with jet multiplicity from >= 1 to >= 4. In each jet
multiplicity sample the differential and cumulative cross sections with respect
to the transverse energy of the n^(th)-leading jet are measured. For W+>=2 jets
the differential cross section with respect to the 2-leading jets invariant
mass m_(j_(1)j_(2)) and angular separation Delta R_(j_(1)j_(2)) is also
reported. The data are compared to predictions from Monte Carlo simulations.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:51:20 GMT"
}
] | 2019-08-13T00:00:00 | [
[
"Messina",
"Andrea",
"",
"for the CDF Collaboration"
]
] |
0708.1381 | Claudia Filippi | Felipe Cordova, L. Joubert Doriol, Andrei Ipatov, Mark E. Casida,
Claudia Filippi, and Alberto Vela | Troubleshooting Time-Dependent Density-Functional Theory for
Photochemical Applications: Oxirane | 19 pages, 17 figures, submitted to the Journal of Chemical Physics | Felipe Cordova, L. Joubert Doriol, Andrei Ipatov, Mark E. Casida,
Claudia Filippi, and Alberto Vela, J. Chem. Phys. 127, 164111 (2007) | 10.1063/1.2786997 | null | cond-mat.other | null | The development of analytic-gradient methodology for excited states within
conventional time-dependent density-functional theory (TDDFT) would seem to
offer a relatively inexpensive alternative to better established
quantum-chemical approaches for the modeling of photochemical reactions.
However, even though TDDFT is formally exact, practical calculations involve
the use of approximate functionals, in particular the TDDFT adiabatic
approximation, whose use in photochemical applications must be further
validated. Here, we investigate the prototypical case of the symmetric CC ring
opening of oxirane. We demonstrate by direct comparison with the results of
high-quality quantum Monte Carlo calculations that, far from being an
approximation on TDDFT, the Tamm-Dancoff approximation (TDA) is a practical
necessity for avoiding triplet instabilities and singlet near instabilities,
thus helping maintain energetically reasonable excited-state potential energy
surfaces during bond breaking. Other difficulties one would encounter in
modeling oxirane photodynamics are pointed out but none of these is likely to
prevent a qualitatively correct TDDFT/TDA description of photochemistry in this
prototypical molecule.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 08:55:27 GMT"
}
] | 2010-08-11T00:00:00 | [
[
"Cordova",
"Felipe",
""
],
[
"Doriol",
"L. Joubert",
""
],
[
"Ipatov",
"Andrei",
""
],
[
"Casida",
"Mark E.",
""
],
[
"Filippi",
"Claudia",
""
],
[
"Vela",
"Alberto",
""
]
] |
0708.1382 | Shaun Cole | Hannah Parkinson, Shaun Cole, John Helly | Generating Dark Matter Halo Merger Trees | We thank Yu Lu for spotting errors in the appendix and helping
identify an error in the coded algorithm. The (online) code and typos have
been corrected. The fits and plots in the paper have been redone and match
the (in press) MNRAS version | null | 10.1111/j.1365-2966.2007.12517.x | null | astro-ph | null | We present a new Monte-Carlo algorithm to generate merger trees describing
the formation history of dark matter halos. The algorithm is a modification of
the algorithm of Cole et al (2000) used in the GALFORM semi-analytic galaxy
formation model. As such, it is based on the Extended Press-Schechter theory
and so should be applicable to hierarchical models with a wide range of power
spectra and cosmological models. It is tuned to be in accurate agreement with
the conditional mass functions found in the analysis of merger trees extracted
from the LCDM Millennium N-body simulation. We present a comparison of its
predictions not only with these conditional mass functions, but also with
additional statistics of the Millennium Simulation halo merger histories. In
all cases we find it to be in good agreement with the Millennium Simulation and
thus it should prove to be a very useful tool for semi-analytic models of
galaxy formation and for modelling hierarchical structure formation in general.
We have made our merger tree generation code and code to navigate the trees
available at http://star-www.dur.ac.uk/~cole/merger_trees .
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:00:25 GMT"
},
{
"version": "v2",
"created": "Wed, 26 Sep 2007 16:12:41 GMT"
},
{
"version": "v3",
"created": "Thu, 22 Nov 2007 11:05:12 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Parkinson",
"Hannah",
""
],
[
"Cole",
"Shaun",
""
],
[
"Helly",
"John",
""
]
] |
0708.1383 | Cristiano Guidorzi | C. Guidorzi, S.D. Vergani, S. Sazonov, S. Covino, D. Malesani, S.
Molkov, E. Palazzi, P. Romano, S. Campana, G. Chincarini, D. Fugazza, A.
Moretti, G. Tagliaferri, A. Llorente, J. Gorosabel, L.A. Antonelli, M.
Capalbi, G. Cusumano, P. D'Avanzo, V. Mangano, N. Masetti, E. Meurs, T.
Mineo, E. Molinari, D.C. Morris, L. Nicastro, K.L. Page, M. Perri, B.
Sbarufatti, G. Stratta, R. Sunyaev, E. Troja, F.M. Zerbi | GRB 070311: a direct link between the prompt emission and the afterglow | 14 pages, 11 figures, 4 tables, accepted to A&A | Astron.Astrophys. 474 (2007) 793-805 | 10.1051/0004-6361:20078254 | null | astro-ph | null | We present prompt gamma-ray, early NIR/optical, late optical and X-ray
observations of the peculiar GRB 070311 discovered by INTEGRAL, in order to
gain clues on the mechanisms responsible for the prompt gamma-ray pulse as well
as for the early and late multi-band afterglow of GRB 070311. We fitted with
empirical functions the gamma-ray and optical light curves and scaled the
result to the late time X-rays. The H-band light curve taken by REM shows two
pulses peaking 80 and 140 s after the peak of the gamma-ray burst and possibly
accompanied by a faint gamma-ray tail. Remarkably, the late optical and X-ray
afterglow underwent a major rebrightening between 3x10^4 and 2x10^5 s after the
burst with an X-ray fluence comparable with that of the prompt emission
extrapolated in the same band. Notably, the time profile of the late
rebrightening can be described as the combination of a time-rescaled version of
the prompt gamma-ray pulse and an underlying power law. This result supports a
common origin for both prompt and late X-ray/optical afterglow rebrightening of
GRB 070311 within the external shock scenario. The main fireball would be
responsible for the prompt emission, while a second shell would produce the
rebrightening when impacting the leading blastwave in a refreshed shock
(abridged).
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:02:01 GMT"
}
] | 2007-10-27T00:00:00 | [
[
"Guidorzi",
"C.",
""
],
[
"Vergani",
"S. D.",
""
],
[
"Sazonov",
"S.",
""
],
[
"Covino",
"S.",
""
],
[
"Malesani",
"D.",
""
],
[
"Molkov",
"S.",
""
],
[
"Palazzi",
"E.",
""
],
[
"Romano",
"P.",
""
],
[
"Campana",
"S.",
""
],
[
"Chincarini",
"G.",
""
],
[
"Fugazza",
"D.",
""
],
[
"Moretti",
"A.",
""
],
[
"Tagliaferri",
"G.",
""
],
[
"Llorente",
"A.",
""
],
[
"Gorosabel",
"J.",
""
],
[
"Antonelli",
"L. A.",
""
],
[
"Capalbi",
"M.",
""
],
[
"Cusumano",
"G.",
""
],
[
"D'Avanzo",
"P.",
""
],
[
"Mangano",
"V.",
""
],
[
"Masetti",
"N.",
""
],
[
"Meurs",
"E.",
""
],
[
"Mineo",
"T.",
""
],
[
"Molinari",
"E.",
""
],
[
"Morris",
"D. C.",
""
],
[
"Nicastro",
"L.",
""
],
[
"Page",
"K. L.",
""
],
[
"Perri",
"M.",
""
],
[
"Sbarufatti",
"B.",
""
],
[
"Stratta",
"G.",
""
],
[
"Sunyaev",
"R.",
""
],
[
"Troja",
"E.",
""
],
[
"Zerbi",
"F. M.",
""
]
] |
0708.1384 | Wilfried Domainko | W. Domainko, W. Benbow, J. A. Hinton, O. Martineau-Huynh, M. de
Naurois, D. Nedbal, G. Pedaletti, G. Rowell (for the H.E.S.S. Collaboration) | H.E.S.S. observations of galaxy clusters | Contribution to the 30th ICRC, Merida Mexico, July 2007 | null | null | null | astro-ph | null | Clusters of galaxies, the largest gravitationally bound objects in the
universe, are expected to contain a significant population of hadronic and
leptonic cosmic rays. Potential sources for these particles are merger and
accretion shocks, starburst driven galactic winds and radio galaxies.
Furthermore, since galaxy clusters confine cosmic ray protons up to energies of
at least 1 PeV for a time longer than the Hubble time they act as storehouses
and accumulate all the hadronic particles which are accelerated within them.
Consequently clusters of galaxies are potential sources of VHE (> 100 GeV)
gamma rays. Motivated by these considerations, promising galaxy clusters are
observed with the H.E.S.S. experiment as part of an ongoing campaign. Here,
upper limits for the VHE gamma ray emission for the Abell 496 and Coma cluster
systems are reported.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:02:26 GMT"
}
] | 2019-08-14T00:00:00 | [
[
"Domainko",
"W.",
"",
"for the H.E.S.S. Collaboration"
],
[
"Benbow",
"W.",
"",
"for the H.E.S.S. Collaboration"
],
[
"Hinton",
"J. A.",
"",
"for the H.E.S.S. Collaboration"
],
[
"Martineau-Huynh",
"O.",
"",
"for the H.E.S.S. Collaboration"
],
[
"de Naurois",
"M.",
"",
"for the H.E.S.S. Collaboration"
],
[
"Nedbal",
"D.",
"",
"for the H.E.S.S. Collaboration"
],
[
"Pedaletti",
"G.",
"",
"for the H.E.S.S. Collaboration"
],
[
"Rowell",
"G.",
"",
"for the H.E.S.S. Collaboration"
]
] |
0708.1385 | Ryo Okamoto | Tomohisa Nagata, Ryo Okamoto, Jeremy L. O'Brien, Keiji Sasaki, and
Shigeki Takeuchi | Beating the Standard Quantum Limit with Four Entangled Photons | 5 pages, 4 figures Author name was slightly modified | Science 316, 726-729 (2007) | 10.1126/science.1138007 | null | quant-ph | null | Precision measurements are important across all fields of science. In
particular, optical phase measurements can be used to measure distance,
position, displacement, acceleration and optical path length. Quantum
entanglement enables higher precision than would otherwise be possible. We
demonstrate an optical phase measurement with an entangled four photon
interference visibility greater than the threshold to beat the standard quantum
limit--the limit attainable without entanglement. These results open the way
for new high-precision measurement applications.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:18:44 GMT"
},
{
"version": "v2",
"created": "Mon, 22 Oct 2007 22:31:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Nagata",
"Tomohisa",
""
],
[
"Okamoto",
"Ryo",
""
],
[
"O'Brien",
"Jeremy L.",
""
],
[
"Sasaki",
"Keiji",
""
],
[
"Takeuchi",
"Shigeki",
""
]
] |
0708.1386 | Etienne Brion | E. Brion, K. Moelmer and M. Saffman | Quantum computing with collective ensembles of multi-level systems | 4 pages, 4 figures | null | 10.1103/PhysRevLett.99.260501 | null | quant-ph | null | We propose a new physical approach for encoding and processing of quantum
information in ensembles of multi-level quantum systems, where the different
bits are not carried by individual particles but associated with the collective
population of different internal levels. One- and two-bit gates are implemented
by collective internal state transitions taking place in the presence of an
excitation blockade mechanism which restricts the population of each internal
state to the values zero and unity. 10-20 bit quantum computers can be built
via this scheme in single trapped clouds of ground state atoms subject to the
Rydberg excitation blockade mechanism, and the linear dependence between
register size and the number of internal quantum states in atoms offers
realistic means to reach larger registers.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:31:58 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Brion",
"E.",
""
],
[
"Moelmer",
"K.",
""
],
[
"Saffman",
"M.",
""
]
] |
0708.1387 | Hiroki Wadati | H. Wadati, A. Maniwa, A. Chikamatsu, I. Ohkubo, H. Kumigashira, M.
Oshima, A. Fujimori, M. Lippmaa, M. Kawasaki, H. Koinuma | In-situ photoemission study of Pr_{1-x}Ca_xMnO_3 epitaxial thin films
with suppressed charge fluctuations | 5 pages, 4 figures | Phys. Rev. Lett. 100, 026402 (2008) | 10.1103/PhysRevLett.100.026402 | null | cond-mat.str-el cond-mat.mtrl-sci | null | We have performed an {\it in-situ} photoemission study of Pr_{1-x}Ca_xMnO_3
(PCMO) thin films grown on LaAlO_3 (001) substrates and observed the effect of
epitaxial strain on the electronic structure. We found that the chemical
potential shifted monotonically with doping, unlike bulk PCMO, implying the
disappearance of incommensurate charge fluctuations of bulk PCMO. In the
valence-band spectra, we found a doping-induced energy shift toward the Fermi
level (E_F) but there was no spectral weight transfer, which was observed in
bulk PCMO. The gap at E_F was clearly seen in the experimental band dispersions
determined by angle-resolved photoemission spectroscopy and could not be
explained by the metallic band structure of the C-type antiferromagnetic state,
probably due to localization of electrons along the ferromagnetic chain
direction or due to another type of spin-orbital ordering.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:55:17 GMT"
},
{
"version": "v2",
"created": "Fri, 17 Aug 2007 15:51:17 GMT"
}
] | 2008-01-17T00:00:00 | [
[
"Wadati",
"H.",
""
],
[
"Maniwa",
"A.",
""
],
[
"Chikamatsu",
"A.",
""
],
[
"Ohkubo",
"I.",
""
],
[
"Kumigashira",
"H.",
""
],
[
"Oshima",
"M.",
""
],
[
"Fujimori",
"A.",
""
],
[
"Lippmaa",
"M.",
""
],
[
"Kawasaki",
"M.",
""
],
[
"Koinuma",
"H.",
""
]
] |
0708.1388 | A. de Visser | N.T. Huy, A. Gasparini, D.E. de Nijs, Y. Huang, J.C.P. Klaasse, T.
Gortenmulder, A. de Visser, A. Hamann, T. Gorlach, H. v. Lohneysen | Superconductivity on the border of weak itinerant ferromagnetism in
UCoGe | 4 pages, 4 figures; PRL, in print | Phys. Rev. Lett. 99, 067006-1:4 (2007) | 10.1103/PhysRevLett.99.067006 | null | cond-mat.supr-con cond-mat.str-el | null | We report the coexistence of ferromagnetic order and superconductivity in
UCoGe at ambient pressure. Magnetization measurements show that UCoGe is a weak
ferromagnet with a Curie temperature T_{C}= 3 K and a small ordered moment
$m_{0}$= 0.03 $\mu_B$. Superconductivity is observed with a resistive
transition temperature T_{s} = 0.8 K for the best sample. Thermal-expansion and
specific-heat measurements provide solid evidence for bulk magnetism and
superconductivity. The proximity to a ferromagnetic instability, the defect
sensitivity of T_{s}, and the absence of Pauli limiting, suggest triplet
superconductivity mediated by critical ferromagnetic fluctuations.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:42:08 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Huy",
"N. T.",
""
],
[
"Gasparini",
"A.",
""
],
[
"de Nijs",
"D. E.",
""
],
[
"Huang",
"Y.",
""
],
[
"Klaasse",
"J. C. P.",
""
],
[
"Gortenmulder",
"T.",
""
],
[
"de Visser",
"A.",
""
],
[
"Hamann",
"A.",
""
],
[
"Gorlach",
"T.",
""
],
[
"Lohneysen",
"H. v.",
""
]
] |
0708.1389 | Sean McNamara | S. McNamara, R. Garc\'ia-Rojo, H.J. Herrmann | Microscopic origin of granular ratcheting | 13 pages, 18 figures | null | 10.1103/PhysRevE.77.031304 | null | cond-mat.soft | null | Numerical simulations of assemblies of grains under cyclic loading exhibit
``granular ratcheting'': a small net deformation occurs with each cycle,
leading to a linear accumulation of deformation with cycle number. We show that
this is due to a curious property of the most frequently used models of the
particle-particle interaction: namely, that the potential energy stored in
contacts is path-dependent. There exist closed paths that change the stored
energy, even if the particles remain in contact and do not slide. An
alternative method for calculating the tangential force removes granular
ratcheting.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:50:08 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"McNamara",
"S.",
""
],
[
"García-Rojo",
"R.",
""
],
[
"Herrmann",
"H. J.",
""
]
] |
0708.1390 | Stefano Zippilli | Sonia Fern\'andez-Vidal, Stefano Zippilli, and Giovanna Morigi | Non-linear optics with two trapped atoms | 11 pages, 8 figures | Phys. Rev. A 76, 053829 (2007) | 10.1103/PhysRevA.76.053829 | null | quant-ph | null | We show theoretically that two atomic dipoles in a resonator constitute a
non-linear medium, whose properties can be controlled through the relative
position of the atoms inside the cavity and the detuning and intensity of the
driving laser. We identify the parameter regime where the system operates as a
parametric amplifier, based on the cascade emission of the collective dipole of
the atoms, and determine the corresponding spectrum of squeezing of the field
at the cavity output. This dynamics could be observed as a result of
self-organization of laser-cooled atoms in resonators.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:54:42 GMT"
}
] | 2007-12-17T00:00:00 | [
[
"Fernández-Vidal",
"Sonia",
""
],
[
"Zippilli",
"Stefano",
""
],
[
"Morigi",
"Giovanna",
""
]
] |
0708.1391 | Olaf Hohm | Johan Engquist, Olaf Hohm | Geometry and dynamics of higher-spin frame fields | 30 pages, uses youngtab.sty, v2: minor changes, references added | JHEP 0804:101,2008 | 10.1088/1126-6708/2008/04/101 | ITP-UU-07/40, SPIN-07/28 | hep-th | null | We give a systematic account of unconstrained free bosonic higher-spin fields
on D-dimensional Minkowski and (Anti-)de Sitter spaces in the frame formalism.
The generalized spin connections are determined by solving a chain of
torsion-like constraints. Via a generalization of the vielbein postulate these
allow to determine higher-spin Christoffel symbols, whose relation to the de
Wit--Freedman connections is discussed. We prove that the generalized Einstein
equations, despite being of higher-derivative order, give rise to the AdS
Fronsdal equations in the compensator formulation. To this end we derive
Damour-Deser identities for arbitrary spin on AdS. Finally we discuss the
possibility of a geometrical and local action principle, which is manifestly
invariant under unconstrained higher-spin symmetries.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 09:58:09 GMT"
},
{
"version": "v2",
"created": "Tue, 30 Oct 2007 13:38:28 GMT"
}
] | 2009-06-11T00:00:00 | [
[
"Engquist",
"Johan",
""
],
[
"Hohm",
"Olaf",
""
]
] |
0708.1392 | Dieter Heiss | W.D. Heiss | Chirality of wave functions for three coalescing levels | Manuscript has been discussed in June 2007 with the experimental
group under Professor Achim Richter at the TU Darmstadt. It has been
presented at the 6th International Workshop on Pseudo Hermitian Hamiltonians,
London, 16-18 July 2007. An expanded version is being prepared for
publication. 3 Figures, 11 pages | null | 10.1088/1751-8113/41/24/244010 | null | quant-ph | null | The coalescence of three levels has particular attractive features. Even
though it may be difficult to realise such event in the laboratory (three
additional real parameters must be adjusted), to take up the challenge seems
worthwhile. In the same way as the chiral behaviour of a usual EP can give a
direction on a line, the state vectors in the vicinity of an EP3 provide an
orientation in the plane. The distinction between left and right handedness
depends on the distribution of the widths of the three levels in the vicinity
of the point of coalescence.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:10:26 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Heiss",
"W. D.",
""
]
] |
0708.1393 | Taichiro Kugo | Makoto Kobayashi, Taichiro Kugo and Tatsuya Tokunaga | Electric Dipole Moments of Dyon and `Electron' | 16pages, no figures, PTPTeX, typos corrected, published version | Prog.Theor.Phys.118:921-934,2007 | 10.1143/PTP.118.921 | KEK-TH-1166, YITP-07-48 | hep-th | null | The electric and magnetic dipole moments of dyon fermions are calculated
within N=2 supersymmetric Yang-Mills theory including the theta-term. It is
found, in particular, that the gyroelectric ratio deviates from the canonical
value of 2 for the monopole fermion (n_m=1,n_e=0) in the case theta\not=0.
Then, applying the S-duality transformation to the result for the dyon
fermions, we obtain an explicit prediction for the electric dipole moment (EDM)
of the charged fermion (`electron'). It is thus seen that the approach
presented here provides a novel method for computing the EDM induced by the
theta-term.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:14:27 GMT"
},
{
"version": "v2",
"created": "Tue, 8 Jan 2008 00:46:06 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kobayashi",
"Makoto",
""
],
[
"Kugo",
"Taichiro",
""
],
[
"Tokunaga",
"Tatsuya",
""
]
] |
0708.1394 | Ferenc Jarai-Szabo | F. Jarai-Szabo, L. Nagy | Semiclassical description of the kinematically complete experiments | 9 pages, 6 figures | F. Jarai-Szabo, L. Nagy, J. Phys. B: At. Mol. Opt. Phys. 40 (2007)
4259 - 4267 | 10.1088/0953-4075/40/21/012 | null | physics.atom-ph | null | Based on the semiclassical, impact parameter method a theoretical model is
constructed to calculate totally differential cross sections for single
ionization of helium by impact with fast C$^{6+}$ ions. Good agreement with the
experiment is achieved in the scattering plane, while in the perpendicular
plane a similar structure to that observed experimentally is obtained. The
contribution of different partial waves to the cross section is also
investigated.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:29:17 GMT"
},
{
"version": "v2",
"created": "Mon, 22 Oct 2007 16:38:55 GMT"
}
] | 2007-10-22T00:00:00 | [
[
"Jarai-Szabo",
"F.",
""
],
[
"Nagy",
"L.",
""
]
] |
0708.1395 | Petr Marek | Petr Marek, Jaromir Fiurasek, Boris Hage, Alexander Franzen, James
DiGugliemo, Roman Schnabel | Multiple copy distillation and purification of phase diffused squeezed
states | 11 pages, 13 figures | Phys. Rev. A, 053820 (2007) | 10.1103/PhysRevA.76.053820 | null | quant-ph | null | We provide a detailed theoretical analysis of multiple copy purification and
distillation protocols for phase diffused squeezed states of light. The
standard iterative distillation protocol is generalized to a collective
purification of an arbitrary number of N copies. We also derive a
semi-analytical expression for the asymptotic limit of the iterative
distillation and purification protocol and discuss its properties.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:29:54 GMT"
},
{
"version": "v2",
"created": "Fri, 16 Nov 2007 10:24:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Marek",
"Petr",
""
],
[
"Fiurasek",
"Jaromir",
""
],
[
"Hage",
"Boris",
""
],
[
"Franzen",
"Alexander",
""
],
[
"DiGugliemo",
"James",
""
],
[
"Schnabel",
"Roman",
""
]
] |
0708.1396 | Jonn Miritzis | J. Miritzis | Oscillatory behavior of closed isotropic models in second order gravity
theory | 16 pages, 3 figures. With some minor improvements. To appear in
General Relativity and Gravitation | Gen.Rel.Grav.41:49-65,2009 | 10.1007/s10714-008-0651-3 | null | gr-qc | null | Homogeneous and isotropic models are studied in the Jordan frame of the
second order gravity theory. The late time evolution of the models is analysed
with the methods of the dynamical systems. The normal form of the dynamical
system has periodic solutions for a large set of initial conditions. This
implies that an initially expanding closed isotropic universe may exhibit
oscillatory behaviour.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:33:22 GMT"
},
{
"version": "v2",
"created": "Tue, 11 Mar 2008 09:09:28 GMT"
}
] | 2009-01-16T00:00:00 | [
[
"Miritzis",
"J.",
""
]
] |
0708.1397 | Naoko Kanaeda | Naoko Kanaeda, Tetsuo Deguchi | Diffusion of a ring polymer in good solution via the Brownian dynamics | 11 pages, 4 figures | J. Phys. A: Math. Theor. 41 (2008) 145004 | 10.1088/1751-8113/41/14/145004 | null | cond-mat.soft | null | Diffusion constants D_{R} and D_{L} of ring and linear polymers of the same
molecular weight in a good solvent, respectively, have been evaluated through
the Brownian dynamics with hydrodynamic interaction. The ratio $C=D_{R}/D_{L}$,
which should be universal in the context of the renormalization group, has been
estimated as $C= 1.11 \pm 0.01$ for the large-N limit. It should be consistent
with that of synthetic polymers, while it is smaller than that of DNAs such as
$C \approx 1.3$. Furthermore, the probability of the ring polymer being a
nontrivial knot is found to be very small, while bond crossings may occur at
almost all time steps in the present simulation that realizes the good solvent
conditions.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:34:23 GMT"
},
{
"version": "v2",
"created": "Mon, 21 Apr 2008 05:09:54 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kanaeda",
"Naoko",
""
],
[
"Deguchi",
"Tetsuo",
""
]
] |
0708.1398 | Chris Clarkson | Chris Clarkson (Cape Town) | A covariant approach for perturbations of rotationally symmetric
spacetimes | 13 pages | Phys.Rev.D76:104034,2007 | 10.1103/PhysRevD.76.104034 | null | gr-qc | null | We present a covariant decomposition of Einstein's Field Equations which is
particularly suitable for perturbations of spherically symmetric -- and general
locally rotationally symmetric -- spacetimes. Based upon the utility of the 1+3
covariant approach to perturbation theory in cosmology, the semi-tetrad, 1+1+2
approach presented here should be useful for analysing perturbations of a
variety of systems in a covariant and gauge-invariant manner. Such applications
range from stellar objects to cosmological models such as the spherically
symmetric Lemaitre-Tolman-Bondi solutions or the class of locally rotationally
symmetric Bianchi models.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 10:41:57 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Clarkson",
"Chris",
"",
"Cape Town"
]
] |
0708.1399 | Anastasios Petkou | A. Fotopoulos, N. Irges, A. C. Petkou and M. Tsulaia | Higher-Spin Gauge Fields Interacting with Scalars: The Lagrangian Cubic
Vertex | 26 pages, v2: references added | JHEP 0710:021,2007 | 10.1088/1126-6708/2007/10/021 | null | hep-th | null | We apply a recently presented BRST procedure to construct the Largangian
cubic vertex of higher-spin gauge field triplets interacting with massive free
scalars. In flat space, the spin-s triplet propagates the series of irreducible
spin-s, s-2,..,0/1 modes which couple independently to corresponding conserved
currents constructed from the scalars. The simple covariantization of the flat
space result is not enough in AdS, as new interaction vertices appear. We
present in detail the cases of spin-2 and spin-3 triplets coupled to scalars.
Restricting to a single irreducible spin-s mode we uncover previously obtained
results. We also present an alternative derivation of the lower spin results
based on the idea that higher-spin gauge fields arise from the gauging of
higher derivative symmetries of free matter Lagrangians. Our results can be
readily applied to holographic studies of higher-spin gauge theories.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:17:47 GMT"
},
{
"version": "v2",
"created": "Mon, 8 Oct 2007 15:42:39 GMT"
}
] | 2009-06-11T00:00:00 | [
[
"Fotopoulos",
"A.",
""
],
[
"Irges",
"N.",
""
],
[
"Petkou",
"A. C.",
""
],
[
"Tsulaia",
"M.",
""
]
] |
0708.1400 | JeongHyeong Park | Y. D. Chai, S. H. Chun, J. H. Park, and K. Sekigawa | Remarks on $\eta$-Einstein unit tangent bundles | 15 pages | null | null | null | math.DG | null | We study the geometric properties of the base manifold for the unit tangent
bundle satisfying the $\eta$-Einstein condition with the standard contact
metric structure. One of the main theorems is that the unit tangent bundle of
4-dimensional Einstein manifold, equipped with the canonical contact metric
structure, is $\eta$-Einstein manifold if and only if base manifold is the
space of constant sectional curvature 1 or 2.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:21:51 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Chai",
"Y. D.",
""
],
[
"Chun",
"S. H.",
""
],
[
"Park",
"J. H.",
""
],
[
"Sekigawa",
"K.",
""
]
] |
0708.1401 | Thomas Colignatus | Thomas Colignatus | Data selection and confounding in the court case of Lucia de Berk | 17 pages, PDF from Mathematica notebook | null | null | TCCE-2007-08-09 | stat.AP | null | The nurse Lucia de Berk was convicted by the Dutch courts as a serial killer
with 7 murders and 3 attempts at murder in three hospitals where she worked.
The nurse however always professed her innocence and indeed was never observed
in such an act of murder. The courts based their decision on circumstantial
evidence and upon the use of statistics. In the appeal court, the use of
statistical calculations was repealed but the use of "data" and "statistical
insights" were not excluded. The trial hinged importantly on the role of
statistics and data gathering. It appears that data selection and confounding
feature strongly in this case. The notion of "nominal correlation" can be used
to highlight those two features. This suggests a mistrial with the conviction
of an innocent person.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:28:07 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Colignatus",
"Thomas",
""
]
] |
0708.1402 | Pranab Ghosh | Sambaran Banerjee and Pranab Ghosh | Evolution of Compact-Binary Populations in Globular Clusters: A
Boltzmann Study. I. The Continuous Limit | 42 pages, 9 figures (1 color figure). Accepted for publication by the
Astrophysical Journal August 7, 2007 | null | 10.1086/522486 | null | astro-ph | null | We explore a Boltzmann scheme for studying the evolution of compact binary
populations of globular clusters. We include processes of compact-binary
formation by tidal capture and exchange encounters, binary destruction by
dissociation and other mechanisms, and binary hardening by encounters,
gravitational radiation and magnetic braking, as also the orbital evolution
during mass transfer, following Roche lobe contact. For the encounter processes
which are stochastic in nature, we study the probabilistic, continuous limit in
this introductory work, deferring the specific handling of the stochastic terms
to the next step. We focus on the evolution of (a) the number of X-ray sources
N_{XB} in globular clusters, and (b) the orbital-period distribution of the
X-ray binaries, as a result of the above processes. We investigate the
dependence of N_{XB} on two essential cluster properties, namely, the star-star
and star-binary encounter-rate parameters 'Gamma' and 'gamma', which we call
Verbunt parameters. We compare our model results with observation, showing that
the model values of N_{XB} and their expected scaling with the Verbunt
parameters are in good agreement with results from recent X-ray observations of
Galactic globular clusters, encouraging us to build more detailed models.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:31:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Banerjee",
"Sambaran",
""
],
[
"Ghosh",
"Pranab",
""
]
] |
0708.1403 | JeongHyeong Park | Y. Euh, J. Lee, J. H. Park, K. Sekigawa, and A. Yamada | Four-dimensional almost Hermitian manifolds with vanishing
Tricerri-Vanhecke Bochner curvature tensor | 16 pages | null | null | null | math.DG | null | We study curvature properties of four-dimensional almost Hermitian manifolds
with vanishing Bochner curvature tensor as defined by Tricerri and Vanhecke. We
give local structure theorems for such Kaehler manifolds, and find out several
examples related to the theorems.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:31:07 GMT"
},
{
"version": "v2",
"created": "Thu, 11 Oct 2007 10:33:15 GMT"
}
] | 2007-10-11T00:00:00 | [
[
"Euh",
"Y.",
""
],
[
"Lee",
"J.",
""
],
[
"Park",
"J. H.",
""
],
[
"Sekigawa",
"K.",
""
],
[
"Yamada",
"A.",
""
]
] |
0708.1404 | Steen Hannestad | Steen Hannestad, Georg Raffelt, Yvonne Y. Y. Wong | Unparticle constraints from SN1987A | 4 pages, 1 figure | Phys.Rev.D76:121701,2007 | 10.1103/PhysRevD.76.121701 | MPP-2007-108 | hep-ph astro-ph | null | The existence of an unparticle sector, weakly coupled to the standard model,
would have a profound impact on supernova (SN) physics. Emission of energy into
the unparticle sector from the core of SN1987A would have significantly
shortened the observed neutrino burst. The unparticle interaction with
nucleons, neutrinos, electrons and muons is constrained to be so weak that it
is unlikely to provide any missing-energy signature at colliders. One important
exception are models where scale invariance in the hidden sector is broken by
the Higgs vacuum expectation value. In this case the SN emission is suppressed
by threshold effects.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:54:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hannestad",
"Steen",
""
],
[
"Raffelt",
"Georg",
""
],
[
"Wong",
"Yvonne Y. Y.",
""
]
] |
0708.1405 | J\"urgen Rohrwild | J. Rohrwild | Determination of the magnetic susceptibility of the quark condensate
using radiative heavy meson decays | 21 pages, 4 figures, references added | JHEP 0709:073,2007 | 10.1088/1126-6708/2007/09/073 | null | hep-ph | null | We use a light-cone sum rule (LCSR) analysis of the branching ratios of
radiative meson decays to contrain the value of the magnetic susceptibility of
the quark condensate $\chi(\mu)$. For the first time, we use a complete set of
three-particle distribution amplitudes that enables us to give a consistent
prediction for the branching ratios. Furthermore we will make use of a very
recent update of several non-perturbative parameters. Our final result for
$\chi(\mu= 1 {\rm GeV})= 2.85 \pm 0.5 {\rm GeV}^{-2}$ (assuming asymptotic wave
functions) agrees with the currently used value of $3.15 \pm 0.3 {\rm
GeV}^{-2}$.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:35:52 GMT"
},
{
"version": "v2",
"created": "Thu, 23 Aug 2007 09:37:00 GMT"
}
] | 2009-01-06T00:00:00 | [
[
"Rohrwild",
"J.",
""
]
] |
0708.1406 | M. Sing | M. Sing, J. Meyer, M. Hoinkis, S. Glawion, P. Blaha, G. Gavrila, C. S.
Jacobsen, R. Claessen | Are the renormalized band widths in TTF-TCNQ of structural or electronic
origin? - An angular dependent NEXAFS study | 6 pages, 5 figures | Phys. Rev. B 76, 245119 (2007) | 10.1103/PhysRevB.76.245119 | null | cond-mat.str-el | null | We have performed angle-dependent near-edge x-ray absorption fine structure
measurements in the Auger electron yield mode on the correlated
quasi-one-dimensional organic conductor TTF-TCNQ in order to determine the
orientation of the molecules in the topmost surface layer. We find that the
tilt angles of the molecules with respect to the one-dimensional axis are
essentially the same as in the bulk. Thus we can rule out surface relaxation as
the origin of the renormalized band widths which were inferred from the
analysis of photoemission data within the one-dimensional Hubbard model.
Thereby recent theoretical results are corroborated which invoke long-range
Coulomb repulsion as alternative explanation to understand the spectral
dispersions of TTF-TCNQ quantitatively within an extended Hubbard model.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 11:45:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sing",
"M.",
""
],
[
"Meyer",
"J.",
""
],
[
"Hoinkis",
"M.",
""
],
[
"Glawion",
"S.",
""
],
[
"Blaha",
"P.",
""
],
[
"Gavrila",
"G.",
""
],
[
"Jacobsen",
"C. S.",
""
],
[
"Claessen",
"R.",
""
]
] |
0708.1407 | Olle Gunnarsson | O. Gunnarsson and O. R\"osch | Interplay between electron-phonon and Coulomb interactions in cuprates | 43 pages and 22 figures | J. Phys.: Condens. Matter 20, 043201 (2008) | 10.1088/0953-8984/20/04/043201 | null | cond-mat.str-el cond-mat.mtrl-sci | null | Evidence for strong electron-phonon coupling in high-Tc cuprates is reviewed,
with emphasis on the electron and phonon spectral functions. Effects due to the
interplay between the Coulomb and electron-phonon interactions are studied. For
weakly doped cuprates, the phonon self-energy is strongly reduced due to
correlation effects, while there is no corresponding strong reduction for the
electron self-energy. Polaron formation is studied, focusing on effects of
Coulomb interaction and antiferromagnetic correlations. It is argued that
experimental indications of polaron formation in undoped cuprates are due to a
strong electron-phonon interaction for these systems.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:46:18 GMT"
}
] | 2008-01-17T00:00:00 | [
[
"Gunnarsson",
"O.",
""
],
[
"Rösch",
"O.",
""
]
] |
0708.1408 | Xin Zhang | Xin Zhang | Can black holes be torn up by phantom dark energy in cyclic cosmology? | 6 pages, 2 figures; discussions added | Eur.Phys.J.C60:661-667,2009 | 10.1140/epjc/s10052-009-0967-5 | null | gr-qc astro-ph hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Infinitely cyclic cosmology is often frustrated by the black hole problem. It
has been speculated that this obstacle in cyclic cosmology can be removed by
taking into account a peculiar cyclic model derived from loop quantum cosmology
or the braneworld scenario, in which phantom dark energy plays a crucial role.
In this peculiar cyclic model, the mechanism of solving the black hole problem
is through tearing up black holes by phantom. However, using the theory of
fluid accretion onto black holes, we show in this paper that there exists
another possibility: that black holes cannot be torn up by phantom in this
cyclic model. We discussed this possibility and showed that the masses of black
holes might first decrease and then increase, through phantom accretion onto
black holes in the expanding stage of the cyclic universe.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:02:36 GMT"
},
{
"version": "v2",
"created": "Mon, 5 Nov 2007 12:37:24 GMT"
},
{
"version": "v3",
"created": "Tue, 10 Mar 2009 10:01:14 GMT"
}
] | 2009-04-24T00:00:00 | [
[
"Zhang",
"Xin",
""
]
] |
0708.1409 | Cord Axel M\"uller | Cord A. Mueller | Diffusive spin transport | Lecture notes, published in A. Buchleitner, C. Viviescas, and M.
Tiersch (Eds.), "Entanglement and Decoherence. Foundations and Modern
Trends", Lecture Notes in Physics 768, Springer, Berlin (2009) | Lect. Notes Phys. 768, 277-314 (2009) | 10.1007/978-3-540-88169-8_6 | null | quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Information to be stored and transported requires physical carriers. The
quantum bit of information (qubit) can for instance be realised as the spin 1/2
degree of freedom of a massive particle like an electron or as the spin 1
polarisation of a massless photon. In this lecture, I first use irreducible
representations of the rotation group to characterise the spin dynamics in a
least redundant manner. Specifically, I describe the decoherence dynamics of an
arbitrary spin S coupled to a randomly fluctuating magnetic field in the
Liouville space formalism. Secondly, I discuss the diffusive dynamics of the
particle's position in space due to the presence of randomly placed impurities.
Combining these two dynamics yields a coherent, unified picture of diffusive
spin transport, as applicable to mesoscopic electronic devices or photons
propagating in cold atomic clouds.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:09:39 GMT"
},
{
"version": "v2",
"created": "Sun, 15 Mar 2009 10:39:38 GMT"
}
] | 2009-03-15T00:00:00 | [
[
"Mueller",
"Cord A.",
""
]
] |
0708.1410 | Frank Ferrari | Frank Ferrari, Stanislav Kuperstein and Vincent Wens (U.L. Bruxelles
and Intl. Solvay Inst.) | Glueball operators and the microscopic approach to N=1 gauge theories | 38 pages, 1 figure and 1 appendix included; v2: typos and the list of
references corrected, version to appear in JHEP | JHEP 0710:101,2007 | 10.1088/1126-6708/2007/10/101 | LPTENS-07/34 | hep-th | null | We explain how to generalize Nekrasov's microscopic approach to N=2 gauge
theories to the N=1 case, focusing on the typical example of the U(N) theory
with one adjoint chiral multiplet X and an arbitrary polynomial tree-level
superpotential Tr W(X). We provide a detailed analysis of the generalized
glueball operators and a non-perturbative discussion of the Dijkgraaf-Vafa
matrix model and of the generalized Konishi anomaly equations. We compute in
particular the non-trivial quantum corrections to the Virasoro operators and
algebra that generate these equations. We have performed explicit calculations
up to two instantons, that involve the next-to-leading order corrections in
Nekrasov's Omega-background.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:22:26 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Oct 2007 14:09:34 GMT"
}
] | 2009-06-11T00:00:00 | [
[
"Ferrari",
"Frank",
"",
"U.L. Bruxelles\n and Intl. Solvay Inst."
],
[
"Kuperstein",
"Stanislav",
"",
"U.L. Bruxelles\n and Intl. Solvay Inst."
],
[
"Wens",
"Vincent",
"",
"U.L. Bruxelles\n and Intl. Solvay Inst."
]
] |
0708.1411 | Sajad Sadough | Sajad Sadough (LSS), Pablo Piantanida (LSS), Pierre Duhamel (LSS) | Achievable Outage Rates with Improved Decoding of Bicm Multiband Ofdm
Under Channel Estimation Errors | null | Dans 40th Asilomar Conference on Signals, Systems, and Computers -
40th Asilomar Conference on Signals, Systems, and Computers, Monterey :
\'Etats-Unis d'Am\'erique (2007) | null | null | cs.NI | null | We consider the decoding of bit interleaved coded modulation (BICM) applied
to multiband OFDM for practical scenarios where only a noisy (possibly very
bad) estimate of the channel is available at the receiver. First, a decoding
metric based on the channel it a posteriori probability density, conditioned on
the channel estimate is derived and used for decoding BICM multiband OFDM.
Then, we characterize the limits of reliable information rates in terms of the
maximal achievable outage rates associated to the proposed metric. We also
compare our results with the outage rates of a system using a theoretical
decoder. Our results are useful for designing a communication system where a
prescribed quality of service (QoS), in terms of achievable target rates with
small error probability, must be satisfied even in the presence of imperfect
channel estimation. Numerical results over both realistic UWB and theoretical
Rayleigh fading channels show that the proposed method provides significant
gain in terms of BER and outage rates compared to the classical mismatched
detector, without introducing any additional complexity.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:13:51 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Sadough",
"Sajad",
"",
"LSS"
],
[
"Piantanida",
"Pablo",
"",
"LSS"
],
[
"Duhamel",
"Pierre",
"",
"LSS"
]
] |
0708.1412 | Sefi Ladkani | Sefi Ladkani | Which canonical algebras are derived equivalent to incidence algebras of
posets? | 8 pages; slight revision; to appear in Comm. Algebra | Communications in Algebra 36 (2008), 4599-4606 | 10.1080/00927870802185989 | null | math.RT math.RA | null | We give a full description of all the canonical algebras over an
algebraically closed field that are derived equivalent to incidence algebras of
finite posets. These are the canonical algebras whose number of weights is
either 2 or 3.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:16:05 GMT"
},
{
"version": "v2",
"created": "Thu, 3 Jan 2008 18:40:02 GMT"
}
] | 2009-08-08T00:00:00 | [
[
"Ladkani",
"Sefi",
""
]
] |
0708.1413 | Sajad Sadough | Sajad Sadough (LSS), Pierre Duhamel (LSS) | On Optimal Turbo Decoding of Wideband MIMO-OFDM Systems Under Imperfect
Channel State Information | null | COST2100 Meeting, Lisbon : Portugal (2007) | null | null | cs.NI | null | We consider the decoding of bit interleaved coded modulation (BICM) applied
to both multiband and MIMO OFDM systems for typical scenarios where only a
noisy (possibly very bad) estimate of the channel is provided by sending a
limited number of pilot symbols. First, by using a Bayesian framework involving
the channel a posteriori density, we adopt a practical decoding metric that is
robust to the presence of channel estimation errors. Then this metric is used
in the demapping part of BICM multiband and MIMO OFDM receivers. We also
compare our results with the performance of a mismatched decoder that replaces
the channel by its estimate in the decoding metric. Numerical results over both
realistic UWB and theoretical Rayleigh fading channels show that the proposed
method provides significant gain in terms of bit error rate compared to the
classical mismatched detector, without introducing any additional complexity.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:16:55 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Sadough",
"Sajad",
"",
"LSS"
],
[
"Duhamel",
"Pierre",
"",
"LSS"
]
] |
0708.1414 | Sajad Sadough | Sajad Sadough (LSS), Mahieddine Ichir (LSS), Emmanuel Jaffrot, Pierre
Duhamel (LSS) | Wavelet Based Semi-blind Channel Estimation For Multiband OFDM | null | Dans European Wireless - European Wireless, Paris : France (2007) | null | null | cs.NI | null | This paper introduces an expectation-maximization (EM) algorithm within a
wavelet domain Bayesian framework for semi-blind channel estimation of
multiband OFDM based UWB communications. A prior distribution is chosen for the
wavelet coefficients of the unknown channel impulse response in order to model
a sparseness property of the wavelet representation. This prior yields, in
maximum a posteriori estimation, a thresholding rule within the EM algorithm.
We particularly focus on reducing the number of estimated parameters by
iteratively discarding ``unsignificant'' wavelet coefficients from the
estimation process. Simulation results using UWB channels issued from both
models and measurements show that under sparsity conditions, the proposed
algorithm outperforms pilot based channel estimation in terms of mean square
error and bit error rate and enhances the estimation accuracy with less
computational complexity than traditional semi-blind methods.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:18:36 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Sadough",
"Sajad",
"",
"LSS"
],
[
"Ichir",
"Mahieddine",
"",
"LSS"
],
[
"Jaffrot",
"Emmanuel",
"",
"LSS"
],
[
"Duhamel",
"Pierre",
"",
"LSS"
]
] |
0708.1415 | Alessio Bonato | ZEUS Collaboration: S. Chekanov, et al | Dijet production in diffractive deep inelastic scattering at HERA | 41 pages, 10 figures, 13 tables. Typos corrected in Table 11 | Eur.Phys.J.C52:813-832,2007 | 10.3360/dis.2007.112 | DESY-07-126 | hep-ex | null | The production of dijets in diffractive deep inelastic scattering has been
measured with the ZEUS detector at HERA using an integrated luminosity of $61
\pbi$. The dijet cross section has been measured for virtualities of the
exchanged virtual photon, $5 < Q^2 < 100 \gev^2$, and $\gamma^{*} p$
centre-of-mass energies, 100 < W < 250 GeV. The jets, identified using the
inclusive k_{T} algorithm in the $\gamma^* p$ frame, were required to have a
transverse energy $E^*_{T, \rm jet} > 4 \gev$ and the jet with the highest
transverse energy was required to have $E^*_{T,\rm jet} > 5 \gev$. All jets
were required to be in the pseudorapidity range $-3.5 < \eta^*_{\rm jet} < 0$.
The differential cross sections are compared to leading-order predictions and
next-to-leading-order QCD calculations based on recent diffractive parton
densities extracted from inclusive diffractive deep inelastic scattering data.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:34:20 GMT"
},
{
"version": "v2",
"created": "Tue, 13 Nov 2007 10:41:58 GMT"
}
] | 2010-05-19T00:00:00 | [
[
"ZEUS Collaboration",
"",
""
],
[
"Chekanov",
"S.",
""
]
] |
0708.1416 | Sajad Sadough | Sajad Sadough (LSS), Pablo Piantanida (LSS), Pierre Duhamel (LSS) | MIMO-OFDM Optimal Decoding and Achievable Information Rates Under
Imperfect Channel Estimation | null | Dans The VIII IEEE Workshop on Signal Processing Advances in
Wireless Communications - The VIII IEEE Workshop on Signal Processing
Advances in Wireless Communications, Finlande (2007) | null | null | cs.NI | null | Optimal decoding of bit interleaved coded modulation (BICM) MIMO-OFDM where
an imperfect channel estimate is available at the receiver is investigated.
First, by using a Bayesian approach involving the channel a posteriori density,
we derive a practical decoding metric for general memoryless channels that is
robust to the presence of channel estimation errors. Then, we evaluate the
outage rates achieved by a decoder that uses our proposed metric. The
performance of the proposed decoder is compared to the classical mismatched
decoder and a theoretical decoder defined as the best decoder in the presence
of imperfect channel estimation. Numerical results over Rayleigh block fading
MIMO-OFDM channels show that the proposed decoder outperforms mismatched
decoding in terms of bit error rate and outage capacity without introducing any
additional complexity.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:40:08 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Sadough",
"Sajad",
"",
"LSS"
],
[
"Piantanida",
"Pablo",
"",
"LSS"
],
[
"Duhamel",
"Pierre",
"",
"LSS"
]
] |
0708.1417 | Andras I. Stipsicz | David T. Gay and Andras I. Stipsicz | Symplectic surgeries and normal surface singularities | In the main result additional hypotheses were added and the proof has
been modified accordingly | null | null | null | math.SG math.GT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that every negative definite configuration of symplectic surfaces in
a symplectic 4--manifold has a strongly symplectically convex neighborhood. We
use this to show that, if a negative definite configuration satisfies an
additional negativity condition at each surface in the configuration, and if
the complex singularity with resolution diffeomorphic to a neighborhood of the
configuration has a smoothing, then the configuration can be symplectically
replaced by the smoothing of the singularity. This generalizes the symplectic
rational blowdown procedure used in recent constructions of small exotic
4--manifolds.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:40:50 GMT"
},
{
"version": "v2",
"created": "Tue, 9 Dec 2008 20:45:25 GMT"
}
] | 2008-12-09T00:00:00 | [
[
"Gay",
"David T.",
""
],
[
"Stipsicz",
"Andras I.",
""
]
] |
0708.1418 | Thomas Niehaus | T.A. Niehaus, S. Suhai, N.H. March | Dynamical generalization of a solvable family of two-electron model
atoms with general interparticle repulsion | 5 pages, submitted to J. Phys. A | null | 10.1088/1751-8113/41/8/085304 | null | quant-ph | null | Holas, Howard and March [Phys. Lett. A {\bf 310}, 451 (2003)] have obtained
analytic solutions for ground-state properties of a whole family of
two-electron spin-compensated harmonically confined model atoms whose different
members are characterized by a specific interparticle potential energy
u($r_{12}$). Here, we make a start on the dynamic generalization of the
harmonic external potential, the motivation being the serious criticism
levelled recently against the foundations of time-dependent density-functional
theory (e.g. [J. Schirmer and A. Dreuw, Phys. Rev. A {\bf 75}, 022513 (2007)]).
In this context, we derive a simplified expression for the time-dependent
electron density for arbitrary interparticle interaction, which is fully
determined by an one-dimensional non-interacting Hamiltonian. Moreover, a
closed solution for the momentum space density in the Moshinsky model is
obtained.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 12:45:32 GMT"
},
{
"version": "v2",
"created": "Tue, 30 Oct 2007 14:47:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Niehaus",
"T. A.",
""
],
[
"Suhai",
"S.",
""
],
[
"March",
"N. H.",
""
]
] |
0708.1419 | Arne Lorenz | Arne Lorenz | On Local Integrability Conditions Of Jet Groupoids | 11 pages | null | null | null | math.DG | null | A Jet groupoid R_q over a manifold X is a special Lie groupoid consisting of
q-jets of local diffeomorphisms from X to X. As a subbundle of the q-th order
jet bundle of the trivial bundle X times X, a jet groupoid can be considered as
a nonlinear system of partial differential equations (PDE). This leads to the
concept of formal integrability. On the other hand, each jet groupoid is the
symmetry groupoid of a geometric object, modelled as a section of a natural
bundle. Using the jet groupoids, we give a local characterisation of formal
integrability for transitive jet groupoids in terms of their corresponding
geometric objects.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 16:27:08 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Lorenz",
"Arne",
""
]
] |
0708.1420 | Ralf Aurich | Ralf Aurich, Holger S. Janzer, Sven Lustig, Frank Steiner | Do we Live in a "Small Universe"? | null | Class.Quant.Grav.25:125006,2008 | 10.1088/0264-9381/25/12/125006 | null | astro-ph | null | We compute the effects of a compact flat universe on the angular correlation
function, the angular power spectrum, the circles-in-the-sky signature, and the
covariance matrix of the spherical harmonics coefficients of the cosmic
microwave background radiation using the full Boltzmann physics. Our analysis
shows that the Wilkinson Microwave Anisotropy Probe (WMAP) three-year data are
well compatible with the possibility that we live in a flat 3-torus with volume
~5x10^3 Gpc^3.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:03:31 GMT"
},
{
"version": "v2",
"created": "Tue, 8 Apr 2008 12:53:57 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Aurich",
"Ralf",
""
],
[
"Janzer",
"Holger S.",
""
],
[
"Lustig",
"Sven",
""
],
[
"Steiner",
"Frank",
""
]
] |
0708.1421 | Sadataka Furui | Sadataka Furui and Hideo Nakajima | Roles of the quark field in the infrared lattice Coulomb gauge and
Landau gauge QCD | 7 pages, 9 figures, Lattice2007 proceedings (use PoS.cls) | PoSLAT2007:301,2007 | null | null | hep-lat | null | The effective coupling of QCD is measured by using the gauge configurations
produced by the MILC collaboration in which the Kogut Susskind (KS) fermion is
incorporated and by using that produced by the QCDOC collaboration in which the
domain wall fermion (DWF) is incorporated. We fix the gauge to the Landau gauge
and to the Coulomb gauge. The infrared effective coupling in the Coulomb gauge
agrees with the recent extraction at JLab, but that in the Landau gauge shows
infrared suppression. The suppression is expected to be due to the color
anti-symmetric ghost propagator which in the unquenched configurations has
stronger infrared singularity than the color diagonal ghost propagator. The
Coulomb form factor in the infrared depends on the kind of the fermion
incorporated in the system and the temperature. The quark has the effect of
quenching randomness and the fluctuation of the color anti-symmetric ghost
propagator is reduced in the unquenched configuration, and the Kugo-Ojima
parameter c is closer to 1 in the unquenched configuration than in the quenched
configuration.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:12:38 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Furui",
"Sadataka",
""
],
[
"Nakajima",
"Hideo",
""
]
] |
0708.1422 | Brian Kent | Brian R. Kent | HI Clouds detected towards Virgo with the Arecibo Legacy Fast ALFA
Survey | To appear in Proceedings of IAU Symp #244, "Dark Galaxies and Lost
Baryons", June 2007, 10 pages including 7 figures and 1 table | null | 10.1017/S1743921307013877 | null | astro-ph | null | The Arecibo Legacy Fast ALFA survey is in the process of yielding a complete
HI dataset of the Virgo Cluster and its environs (Giovanelli et al. 2007, Kent
et al., in preparation). Assuming a distance to Virgo of 16.7 Mpc, the minimum
detectable HI mass by ALFALFA is of order 2 x 10^7 Msun. A number of the HI
detections appear to have interesting properties. Some appear associated with,
but offset from, low surface brightness optical counterparts; others, at larger
spatial offsets, may be tidally related to optical counterparts. Yet another
class includes detections which are not identifiable with any optical
counterparts. We present the ALFALFA results on these objects in the Virgo
region, as well as followup aperture synthesis observations obtained with the
VLA.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:22:31 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kent",
"Brian R.",
""
]
] |
0708.1423 | Giovanni Falcone | Giovanni Falcone | A property of cyclotomic polynomials | 4 pages, Problem 10914 in Amer. Math. Monthly 109 (Jan 2002) | null | null | null | math.NT | null | Given two cyclotomic polynomials $\Phi_n(x)$ and $\Phi_m(x)$, $n\not= m$, we
determine the minimal natural number k such that we can write $$k=a(x)\Phi_n
(x)+b(x)\Phi_m(x),$$ with a(x) and b(x) integer polynomials.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:16:12 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Falcone",
"Giovanni",
""
]
] |
0708.1424 | Patrick Pl\"otz | Patrick Pl\"otz | Charge and spin response functions for the Tomonaga model with quadratic
dispersion and different interactions | 10 pages, 6 figures | null | null | null | cond-mat.str-el | null | We derive expressions for the charge and spin response function for the
Tomonaga model with quadratic dispersion and arbitrary (but finite for zero
momentum) interaction. For constant interaction these expressions are analytic
and for other types of interaction only a simple matrix has to be diagonalised.
We use a truncated expansion in particle-hole states with and without inclusion
of correlations in the ground state yielding an exact result for pure
intra-band interaction. We also discuss the possibility of power-laws in the
dynamic structure factor for the spinful and spinless model.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:52:36 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Plötz",
"Patrick",
""
]
] |
0708.1425 | Antoine Gloria | Roberto Alicandro (DAEIMI), Marco Cicalese, Antoine Gloria (INRIA
Rocquencourt) | Convergence analysis of the B\"ol-Reese discrete model for rubber | null | null | null | null | math-ph math.MP math.NA | null | In a recent work, B\"ol and Reese have introduced a discrete model for
polymer networks by means of a finite element modeling. They have also provided
a comparison with real experiments. A key parameter of their model is the size
h of the finite element mesh, that is meant to be small in practice. The aim of
the present work is to study the asymptotic behaviour (and the convergence of
the finite element method) when the meshsize goes to zero. In particular, we
address the properties satisfied by the model at the limit, depending on the
properties of the mesh.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:18:12 GMT"
},
{
"version": "v2",
"created": "Mon, 13 Aug 2007 08:43:38 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Alicandro",
"Roberto",
"",
"DAEIMI"
],
[
"Cicalese",
"Marco",
"",
"INRIA\n Rocquencourt"
],
[
"Gloria",
"Antoine",
"",
"INRIA\n Rocquencourt"
]
] |
0708.1426 | Francoise Heres-Renzetti | J. Mayandi, T. G. Finstad, C. L. Heng, Y. J. Li, A. Thogersen., S.
Foss, H. Klette | A Comparison between 1.5$\mu$m Photoluminescence from Er-Doped Si-Rich
Sio2 Films and (Er,Ge) Co-Doped Sio2 Films | Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions) | Dans European Nano Systems Worshop - ENS 2006, Paris : France
(2006) | null | null | cond-mat.mtrl-sci | null | We have studied the 1.5 $\mu$m photoluminescence (PL) from Er ions after
annealing two different sample sets in the temperature range 500 °C to 1100
°C. The different sample sets were made by magnetron sputtering from
composite targets of Si+SiO2+Er and Ge+SiO2+Er respectively for the different
sample sets. The annealing induces Si - and Ge-nanoclusters respectively in the
different film sets. The PL peak reaches its maximum intensity after annealing
at 700 °C for samples with Ge nanoclusters and after annealing at 800
°C for samples with Si. No luminescence from nanoclusters was detected in
neither sample sets. This is interpreted as an energy transfer from the
nanocluster to Er atoms. Transmission electron microscopy shows that after
annealing to the respective temperature yielding the maximum PL intensity both
the Ge and Si clusters are non-crystalline. Here we mainly compare the spectral
shape of Er luminescence emitted in these different nanostructured matrixes.
The PL spectral shapes are clearly different and witness a different local
environment for the Er ions.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:16:35 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Mayandi",
"J.",
""
],
[
"Finstad",
"T. G.",
""
],
[
"Heng",
"C. L.",
""
],
[
"Li",
"Y. J.",
""
],
[
"Thogersen.",
"A.",
""
],
[
"Foss",
"S.",
""
],
[
"Klette",
"H.",
""
]
] |
0708.1427 | Megan Donahue | Megan Donahue, Andres Jordan, Stefi A. Baum, Patrick Cote, Laura
Ferrarese, Paul Goudfrooij, Duccio Macchetto, Christopher P. O'Dea, James E.
Pringle, James E. Rhoads, William B. Sparks, G. Mark Voit | Infrared Emission from the Nearby Cool Core Cluster Abell 2597 | Accepted at ApJ | null | 10.1086/522575 | null | astro-ph | null | We observed the brightest central galaxy (BCG) in the nearby (z=0.0821) cool
core galaxy cluster Abell 2597 with the IRAC and MIPS instruments on board the
Spitzer Space Telescope. The BCG was clearly detected in all Spitzer
bandpasses, including the 70 and 160 micron wavebands. We report aperture
photometry of the BCG. The spectral energy distribution exhibits a clear excess
in the FIR over a Rayleigh-Jeans stellar tail, indicating a star formation rate
of ~4-5 solar masses per year, consistent with the estimates from the UV and
its H-alpha luminosity. This large FIR luminosity is consistent with that of a
starburst or a Luminous Infrared Galaxy (LIRG), but together with a very
massive and old population of stars that dominate the energy output of the
galaxy. If the dust is at one temperature, the ratio of 70 to 160 micron fluxes
indicate that the dust emitting mid-IR in this source is somewhat hotter than
the dust emitting mid-IR in two BCGs at higher-redshift (z~0.2-0.3) and higher
FIR luminosities observed earlier by Spitzer, in clusters Abell 1835 and Zwicky
3146.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:14:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Donahue",
"Megan",
""
],
[
"Jordan",
"Andres",
""
],
[
"Baum",
"Stefi A.",
""
],
[
"Cote",
"Patrick",
""
],
[
"Ferrarese",
"Laura",
""
],
[
"Goudfrooij",
"Paul",
""
],
[
"Macchetto",
"Duccio",
""
],
[
"O'Dea",
"Christopher P.",
""
],
[
"Pringle",
"James E.",
""
],
[
"Rhoads",
"James E.",
""
],
[
"Sparks",
"William B.",
""
],
[
"Voit",
"G. Mark",
""
]
] |
0708.1428 | Delio Mugnolo | Stefano Cardanobile, Delio Mugnolo | Qualitative properties of coupled parabolic systems of evolution
equations | null | Ann. Sc. Norm. Sup. Pisa, Cl. Sci, V Ser., VII (2008) | null | null | math.FA math.AP | null | We apply functional analytical and variational methods in order to study
well-posedness and qualitative properties of evolution equations on product
Hilbert spaces. To this aim we introduce an algebraic formalism for matrices of
sesquilinear mappings. We apply our results to parabolic problems of different
nature: a coupled diffusive system arising in neurobiology, a strongly damped
wave equation, a heat equation with dynamic boundary conditions, and a general
semilinear Hodgkin--Huxley sytem.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 13:57:30 GMT"
},
{
"version": "v2",
"created": "Wed, 23 Jan 2008 14:08:57 GMT"
}
] | 2010-05-13T00:00:00 | [
[
"Cardanobile",
"Stefano",
""
],
[
"Mugnolo",
"Delio",
""
]
] |
0708.1429 | Matthieu Tristram | Matthieu Tristram (LAL), Ken Ganga (APC) | Data analysis methods for the cosmic microwave background | 41 pages, 21 figures | Rept.Prog.Phys.70:899,2007 | 10.1088/0034-4885/70/6/R02 | LAL 07-81, APC-07-50 | astro-ph | null | In this review, we give an overview of some of the major aspects of data
reduction and analysis for the cosmic microwave background (CMB). Since its
prediction and discovery in the last century, the CMB radiation has proven
itself to be one of our most valuable tools for precision cosmology. Recently,
and especially when combined with complementary cosmological data, measurements
of the CMB anisotropies have provided us with a wealth of quantitive
information about the birth, evolution and structure of our Universe. We begin
with a simple, general introduction to the physics of the CMB, including a
basic overview of the experiments which record CMB data. The focus, however,
will be the data analysis treatment of CMB data sets.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:04:38 GMT"
},
{
"version": "v2",
"created": "Mon, 12 Nov 2007 14:32:48 GMT"
},
{
"version": "v3",
"created": "Tue, 10 Jun 2008 11:29:18 GMT"
}
] | 2009-09-29T00:00:00 | [
[
"Tristram",
"Matthieu",
"",
"LAL"
],
[
"Ganga",
"Ken",
"",
"APC"
]
] |
0708.1430 | Roland Bacher | Roland Bacher (IF) | Determinants related to Dirichlet characters modulo 2, 4 and 8 of
binomial coefficients and the algebra of recurrence matrices | Final version, to appear in International Journal of Algebra and
Computation | International Journal of Algebra and Computation 18, 3 (2008)
535-566 | null | null | math.NT math.RA | null | Using recurrence matrices, defined and described with some details, we study
a few determinants related to evaluations of binomial coefficients on Dirichlet
characters modulo 2, 4 and 8.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:05:35 GMT"
},
{
"version": "v2",
"created": "Wed, 28 Nov 2007 15:19:57 GMT"
},
{
"version": "v3",
"created": "Mon, 12 May 2008 19:41:51 GMT"
}
] | 2008-07-03T00:00:00 | [
[
"Bacher",
"Roland",
"",
"IF"
]
] |
0708.1431 | Philippe Lauren\c{c}ot | Jean-Philippe Bartier and Philippe Lauren\c{c}ot | Gradient estimates for a degenerate parabolic equation with gradient
absorption and applications | null | null | null | null | math.AP | null | Qualitative properties of non-negative solutions to a quasilinear degenerate
parabolic equation with an absorption term depending solely on the gradient are
shown, providing information on the competition between the nonlinear diffusion
and the nonlinear absorption. In particular, the limit as time goes to infinity
of the mass of integrable solutions is identified, together with the rate of
expansion of the support for compactly supported initial data. The persistence
of dead cores is also shown. The proof of these results strongly relies on
gradient estimates which are first established.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:13:28 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Bartier",
"Jean-Philippe",
""
],
[
"Laurençot",
"Philippe",
""
]
] |
0708.1432 | Robert J. McQueeney | J. M. Hill, R. J. McQueeney, Ruqian Wu, K. Dennis, R. W. McCallum, M.
Huang, T. A. Lograsso | Low temperature heat capacity of Fe_{1-x}Ga_{x} alloys with large
magneostriction | 14 pages, 6 figures | null | 10.1103/PhysRevB.77.014430 | null | cond-mat.mtrl-sci | null | The low temperature heat capacity C_{p} of Fe_{1-x}Ga_{x} alloys with large
magnetostriction has been investigated. The data were analyzed in the standard
way using electron ($\gamma T$) and phonon ($\beta T^{3}$) contributions. The
Debye temperature $\Theta_{D}$ decreases approximately linearly with increasing
Ga concentration, consistent with previous resonant ultrasound measurements and
measured phonon dispersion curves. Calculations of $\Theta_{D}$ from lattice
dynamical models and from measured elastic constants C_{11}, C_{12} and C_{44}
are in agreement with the measured data. The linear coefficient of electronic
specific heat $\gamma$ remains relatively constant as the Ga concentration
increases, despite the fact that the magnetoelastic coupling increases. Band
structure calculations show that this is due to the compensation of majority
and minority spin states at the Fermi level.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:15:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Hill",
"J. M.",
""
],
[
"McQueeney",
"R. J.",
""
],
[
"Wu",
"Ruqian",
""
],
[
"Dennis",
"K.",
""
],
[
"McCallum",
"R. W.",
""
],
[
"Huang",
"M.",
""
],
[
"Lograsso",
"T. A.",
""
]
] |
0708.1433 | Dumitru Baleanu | Dumitru Baleanu, Juan J. Trujillo | On exact solutions of a class of fractional Euler-Lagrange equations | 10 pages, LATEX. in press, Nonlinear Dynamics | null | null | null | math-ph math.MP | null | In this paper, first a class of fractional differential equations are
obtained by using the fractional variational principles. We find a fractional
Lagrangian $L(x(t)$, where $_a^cD_t^\alpha x(t))$ and $0<\alpha< 1$, such that
the following is the corresponding Euler-Lagrange %
\begin{equation}_tD_b^\alpha(_a^cD_t^\alpha) x(t)+ b(t,x(t))(_a^cD_t^\alpha
x(t))+f(t,x(t))=0. \end{equation} % At last, exact solutions for some
Euler-Lagrange equations are presented. In particular, we consider the
following equations % \begin{equation}_tD_b^\alpha(_a^cD_t^\alpha x(t))=\lambda
x(t), (\lambda\in R) \end{equation} %
\begin{equation}_tD_b^\alpha(_a^cD_t^\alpha x(t))+g(t)_a^cD_t^\alpha x(t)=f(t),
\end{equation} where g(t) and f(t) are suitable functions.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:15:11 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Baleanu",
"Dumitru",
""
],
[
"Trujillo",
"Juan J.",
""
]
] |
0708.1434 | Thorsten Poeschel | Thomas Schwager and Thorsten Poeschel | Coefficient of Restitution for Viscoelastic Spheres: The Effect of
Delayed Recovery | 11 pages, 2 figures | null | 10.1103/PhysRevE.78.051304 | null | cond-mat.mtrl-sci cond-mat.stat-mech | null | The coefficient of normal restitution of colliding viscoelastic spheres is
computed as a function of the material properties and the impact velocity. From
simple arguments it becomes clear that in a collision of purely repulsively
interacting particles, the particles loose contact slightly before the distance
of the centers of the spheres reaches the sum of the radii, that is, the
particles recover their shape only after they lose contact with their collision
partner. This effect was neglected in earlier calculations which leads
erroneously to attractive forces and, thus, to an underestimation of the
coefficient of restitution. As a result we find a novel dependence of the
coefficient of restitution on the impact rate.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:30:56 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Schwager",
"Thomas",
""
],
[
"Poeschel",
"Thorsten",
""
]
] |
0708.1435 | Jens Teifel | Jens Teifel, G\"unter Mahler | Model Studies on the Quantum Jarzynski Relation | 7 figures | Phys. Rev. E 76, 051126 (2007) | 10.1103/PhysRevE.76.051126 | null | cond-mat.stat-mech | null | We study the quantum Jarzynski relation for driven quantum models embedded in
various environments. We do so by generalizing a proof presented by Mukamel
[Phys. Rev. Lett 90, 170604 (2003)] for closed quantum systems. In this way, we
are able to prove that the Jarzynski relation also holds for a bipartite system
with microcanonical coupling. Furthermore, we show that, under the assumption
that the interaction energy remains constant during the whole process, the
relation is valid even for canonical coupling. The same follows for open
quantum systems at high initial temperatures up to third order of the inverse
temperature. Our analytical study is complemented by a numerical investigation
of a special model system.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:40:04 GMT"
},
{
"version": "v2",
"created": "Tue, 4 Dec 2007 10:39:38 GMT"
}
] | 2007-12-04T00:00:00 | [
[
"Teifel",
"Jens",
""
],
[
"Mahler",
"Günter",
""
]
] |
0708.1436 | Shidong Wang | Shidong Wang, Milena Grifoni | Transport properties of double-walled carbon nanotube quantum dots | 18 pages, 7 figures | null | 10.1103/PhysRevB.77.085431 | null | cond-mat.mes-hall | null | The transport properties of quantum dot (QD) systems based on double-walled
carbon nanotube (DWCNT) are investigated. The interplay between microscopic
structure and strong Coulomb interaction is treated within a bosonization
framework. The linear and nonlinear G-V-V_g characteristics of the QD system is
calculated by starting from the Liouville equation for the reduced density
matrix. Depending on the intershell couplings, an 8-electron periodicity of the
Coulomb blockade peak spacing in the case of commensurate DWCNT QDs and a
4-electron periodicity in the incommensurate case are predicted. The
contribution of excited states of DWCNTs to the nonlinear transport is
investigated as well.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:40:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wang",
"Shidong",
""
],
[
"Grifoni",
"Milena",
""
]
] |
0708.1437 | Marc Arnold Nieper-Wi{\ss}kirchen | Marc A. Nieper-Wisskirchen | Twisted cohomology of the Hilbert schemes of points on surfaces | 16 pages | null | null | null | math.AG math.AT | null | We calculate the cohomology spaces of the Hilbert schemes of points on
surfaces with values in locally constant systems. For that purpose, we
generalise I. Grojnoswki's and H. Nakajima's description of the ordinary
cohomology in terms of a Fock space representation to the twisted case. We
further generalise M. Lehn's work on the action of the Virasoro algebra to the
twisted case.
Building on work by M. Lehn and Ch. Sorger, we then give an explicit
description of the cup-product in the twisted case whenever the surface has a
numerically trivial canonical divisor.
We formulate our results in a way that they apply to the projective and
non-projective case in equal measure.
As an application of our methods, we give explicit models for the cohomology
rings of the generalised Kummer varieties and of a series of certain even
dimensional Calabi--Yau manifolds.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:47:04 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Nieper-Wisskirchen",
"Marc A.",
""
]
] |
0708.1438 | Athina Meli | A. Meli, J. Becker, J. J. Quenby, J. Luenemann | Particle acceleration in relativistic subluminal shock environments | 4 pages, 2 figures, proceedings of the 30th ICRC, Merida, Mexico 2007 | null | null | null | astro-ph | null | The understanding of the particle spectra resulting from acceleration in
relativistic shocks as they occur in extragalactic sources, is essential for
the interpretation of the cosmic ray spectrum above the ankle ($E_p>3\cdot
10^{18}$ eV). It is believed that extragalactic sources like Active Galactic
Nuclei and Gamma Ray Bursts can produce particle spectra up to $E_p\sim
10^{21}$ eV. In this contribution, subluminal shocks are investigated with
respect to different shock boost factors $\Gamma$ and the inclination angle
between the shock normal and the magnetic field $\psi$. A correlation between
the boost factor and the spectral behavior of the emitted particles is found.
The results are compared to Active Galactic Nuclei and Gamma Ray Burst diffuse
cosmic ray contribution and the observed cosmic ray spectrum at the highest
energies.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:51:52 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Meli",
"A.",
""
],
[
"Becker",
"J.",
""
],
[
"Quenby",
"J. J.",
""
],
[
"Luenemann",
"J.",
""
]
] |
0708.1439 | Walton Gutierrez | Walton R. Gutierrez | The Optimal Form of Distribution Networks Applied to the Kidney and Lung | 12 pages, 6 figures | null | null | null | q-bio.TO q-bio.QM | null | A model is proposed to minimize the total volume of the main distribution
networks of fluids in relation to the organ form. The minimization analysis
shows that the overall exterior form of distribution networks is a modified
ellipsoid, a geometric form that is a good approximation to the external
anatomy of the kidney and lung. The variational procedure implementing this
minimization is similar to the traditional isoperimetric theorems of geometry.
A revised version of this preprint that expands Section 4 will be published
in the Journal of Biological Systems, World Scientific Publishing.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:53:39 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Gutierrez",
"Walton R.",
""
]
] |
0708.1440 | Paolo Salucci | Paolo Salucci, Irina A. Yegorova, Niv Drory | The Disk Mass of Spiral Galaxies | 5 pages, 4 Figures accepted to MN | null | 10.1111/j.1365-2966.2008.13295.x | null | astro-ph | null | We derive the disk masses of 18 spiral galaxies of different luminosity and
Hubble Type, both by mass modelling their rotation curves and by fitting their
SED with spectro-photometric models. The good agreement of the estimates
obtained from these two different methods allows us to quantify the reliability
of their performance and to derive very accurate stellar mass-to-light ratio vs
color (and stellar mass) relationships.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:56:39 GMT"
},
{
"version": "v2",
"created": "Fri, 4 Apr 2008 16:39:57 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Salucci",
"Paolo",
""
],
[
"Yegorova",
"Irina A.",
""
],
[
"Drory",
"Niv",
""
]
] |
0708.1441 | Rien van de Weygaert | Rien van de Weygaert, Willem Schaap (Kapteyn Astronomical Institute,
University Groningen, the Netherlands) | The Cosmic Web: Geometric Analysis | 128 pp., 52+1 figures, lecture notes summerschool "Data Analysis in
Cosmology" (Valencia), eds. V. Martinez, E. Saar, E. Martinez-Gonzalez, M.
Pons-Borderia, Springer-Verlag. For high-res version see
http://www.astro.rug.nl/~weygaert/tim1publication/weyval2004.pdf | null | 10.1007/978-3-540-44767-2_11 | null | astro-ph | null | The lecture notes describe the Delaunay Tessellation Field Estimator for
Cosmic Web analysis. The high sensitivity of Voronoi/Delaunay tessellations to
the local point distribution is used to obtain estimates of density and related
quantities. The adaptive and minimum triangulation properties of Delaunay
tessellations are utilized for interpolation to continuous volume-covering
density and velocity fields. The adaptivity to the local density and geometry
preserves three key characteristics of the cosmic matter distribution: 1) its
hierarchical nature,2) its anisotropic weblike morphology, 3) the presence and
structure of voids. The lecture notes discuss the mathematical context and
background of the DTFE method, in essence a first order version of Natural
Neighbour methods, smooth and higher order spatial interpolation techniques.
This is followed by an outline of the DTFE procedure. A series of tests on
spatially complex point distributions provides quantitative information on its
performance and noise characteristics. We conclude with a few cosmological
applications. The reconstruction of the spatial weblike patterns in N-body
simulations and in the 2dFGRS provide a visual impression of DTFE's
performance. The analysis of the velocity divergence pdf and maps obtained of
the velocity flow in the Local Universe (implied by PSCz) illustrate its
promise for probing the dynamics of cosmic structure. The Watershed Void Finder
(Platen et al. 2007), for the study of voids, and Multiscale Morphology Filter
(Aragon-Calvo et al. 2007), for identifying and analyzing weblike networks of
filaments, sheets and clusters, are based upon DTFE density fields. We also
mention SimpleX, a related random lattice radiative transfer formalism
(Ritzerveld & Icke 2006).
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:24:57 GMT"
}
] | 2017-03-08T00:00:00 | [
[
"van de Weygaert",
"Rien",
"",
"Kapteyn Astronomical Institute,\n University Groningen, the Netherlands"
],
[
"Schaap",
"Willem",
"",
"Kapteyn Astronomical Institute,\n University Groningen, the Netherlands"
]
] |
0708.1442 | Athina Meli | A. Meli, P. L. Biermann, S. Dimitrakoudis | Cosmic ray acceleration at modified shocks | 4 pages, 2 figures, proceedings of the 30th ICRC, Merida, Mexico 2007 | null | null | null | astro-ph | null | The non-linear back reaction of accelerated cosmic rays at the shock fronts,
leads to the formation of a smooth precursor with a length scale corresponding
to the diffusive scale of the energetic particles. Past works claimed that
shocklets could be created in the precursor region of a specific shock width,
which might energize few thermal particles to sufficient acceleration and
furthermore this precursor region may act as confining large angle scatterer
for very high energy cosmic rays. On the other hand, it has been shown that the
smoothing of the shock front could lower the acceleration efficiency. These
controversies motivated us to investigate numerically by Monte Carlo
simulations the particle acceleration efficiency in oblique modified shocks.
The results show flatter spectra compared to the spectra of the pressumed sharp
discontinuity shock fronts. The findings are in accordance with theoretical
predictions, since the scattering inside the precursor confines high energy
particles to further scattering, resulting in higher energies making the whole
acceleration process more efficient.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:58:13 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Meli",
"A.",
""
],
[
"Biermann",
"P. L.",
""
],
[
"Dimitrakoudis",
"S.",
""
]
] |
0708.1443 | Peter Krizan | The HERA-B Collaboration | Measurement of D^0, D^+, D_s^+ and D^{*+} Production in Fixed Target 920
GeV Proton-Nucleus Collisions | Submitted to EPJ C | Eur.Phys.J.C52:531-542,2007 | 10.1140/epjc/s10052-007-0427-z | null | hep-ex | null | The inclusive production cross sections of the charmed mesons D^0, D^+, D_s^+
and D^{*+} have been measured in interactions of 920 GeV protons on C, Ti, and
W targets with the HERA-B detector at the HERA storage ring. Differential cross
sections as a function of transverse momentum and Feynman's x variable are
given for the central rapidity region and for transverse momenta up to
$\pT=3.5$ GeV/$c$. The atomic mass number dependence and the leading to
non-leading particle production asymmetries are presented as well.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 14:58:53 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"B Collaboration",
"",
""
]
] |
0708.1444 | Athina Meli | A. Meli, A. Mastichiadis | Efficiency limits of diffusive shock acceleration | 4 pages, 4 figures, proceedings of the 30th ICRC, Merida, Mexico 2007 | null | null | null | astro-ph | null | It is well accepted today that diffusive acceleration in shocks results to
the cosmic ray spectrum formation. This is in principle true for
non-relativistic shocks, since there is a detailed theory covering a large
range of their properties and the resulting power-law spectrum, which is
nevertheless not as efficient to reach the very high energies observed in the
cosmic ray spectrum. On the other hand, the cosmic ray maximum energy and the
resulting spectra from relativistic shocks, are still under investigation and
debate concerning their contribution to the features of the cosmic ray spectrum
and the measured, or implied, cosmic ray radiation from candidate astrophysical
sources. Here, we discuss the efficiency of the first order Fermi (diffusive)
acceleration mechanism up to relativistic shock speeds, presenting Monte Carlo
simulations.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:00:35 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Meli",
"A.",
""
],
[
"Mastichiadis",
"A.",
""
]
] |
0708.1445 | Francoise Heres-Renzetti | P. Kervalishvili | Nanostructures, Magnetic Semiconductors and Spinelectronics | Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions) | Dans European Nano Systems Worshop - ENS 2006, Paris : France
(2006) | null | null | cond-mat.mtrl-sci | null | A short overview is given of recent advances in the field of
nanosemiconductors, which are suitable as materials for spin polarized
transport of charge carriers. On the basis of last theoretical and experimental
achievements it is shown that development of diluted and wide forbidden zone
semiconductors with controlled disorders as well as their molecular structures
is the very prospective way for magnetic semiconductors preparation.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:08:22 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Kervalishvili",
"P.",
""
]
] |
0708.1446 | Eric Falcon | Claudio Falcon (LPS), Eric Falcon (MSC), Umberto Bortolozzo (LPS,
MSC), St\'ephan Fauve (LPS) | Capillary wave turbulence on a spherical fluid surface in low gravity | null | Europhysics Letters (EPL) 86 (2009) 14002 | 10.1209/0295-5075/86/14002 | null | cond-mat.other nlin.CD physics.class-ph physics.flu-dyn | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We report the observation of capillary wave turbulence on the surface of a
fluid layer in a low-gravity environment. In such conditions, the fluid covers
all the internal surface of the spherical container which is submitted to
random forcing. The surface wave amplitude displays power-law spectrum over two
decades in frequency, corresponding to wavelength from $mm$ to a few $cm$. This
spectrum is found in roughly good agreement with wave turbulence theory. Such a
large scale observation without gravity waves has never been reached during
ground experiments. When the forcing is periodic, two-dimensional spherical
patterns are observed on the fluid surface such as subharmonic stripes or
hexagons with wavelength satisfying the capillary wave dispersion relation.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:05:15 GMT"
},
{
"version": "v2",
"created": "Mon, 9 Feb 2009 19:13:11 GMT"
}
] | 2009-05-06T00:00:00 | [
[
"Falcon",
"Claudio",
"",
"LPS"
],
[
"Falcon",
"Eric",
"",
"MSC"
],
[
"Bortolozzo",
"Umberto",
"",
"LPS,\n MSC"
],
[
"Fauve",
"Stéphan",
"",
"LPS"
]
] |
0708.1447 | Francoise Heres-Renzetti | F. Gentile, A. Granaldi, P. Decuzzi | On the adhesion of particles to a cell layer under flow | Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions) | Dans European Nano Systems Worshop - ENS 2006, Paris : France
(2006) | null | null | cond-mat.mtrl-sci | null | The non-specific adhesion of spherical particles to a cell substrate is
analyzed in a parallel plate flow chamber, addressing the effect of the
particle size. Differently from other experiments, the total volume of the
injected particles has been fixed, rather than the total number of particles,
as the diameter d of the particles is changed from 500 nm up to 10 $\mu$m. From
the analysis of the experimental data, simple and instructive scaling adhesion
laws have been derived showing that (i) the number of particles adherent to the
cell layer per unit surface decreases with the size of the particle as d^(-1.7)
; and consequently (ii) the volume of the particles adherent per unit surface
increases with the size of the particles as d^(+1.3). These results are of
importance in the "rational design" of nanoparticles for drug delivery and
biomedical imaging.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:07:35 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Gentile",
"F.",
""
],
[
"Granaldi",
"A.",
""
],
[
"Decuzzi",
"P.",
""
]
] |
0708.1448 | Francoise Heres-Renzetti | F. Tafuri, A. Tagliacozzo, D. Born, D. Stornaiuolo, E. Gambale, D.
Dalena, P. Lucignano, B. Jouault (GES), F. Lombardi, A. Barone, B. L.
Altshuler | Coherent quasiparticle transport in grain boundary junctions employing
high-Tc superconductors | Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions) | Dans European Nano Systems Worshop - ENS 2006, Paris : France
(2006) | null | null | cond-mat.mtrl-sci | null | Magneto-fluctuations of the normal resistance RN have been reproducibly
observed in YBa2Cu3O7-d biepitaxial grain boundary junctions at low
temperatures. We attribute them to mesoscopic transport in narrow channels
across the grain boundary line, occurring in an unusual energy regime. The
Thouless energy appears to be the relevant energy scale. Possible implications
on the understanding of coherent transport of quasiparticles in HTS and of the
dissipation mechanisms are discussed.
| [
{
"version": "v1",
"created": "Fri, 10 Aug 2007 15:08:48 GMT"
}
] | 2007-08-13T00:00:00 | [
[
"Tafuri",
"F.",
"",
"GES"
],
[
"Tagliacozzo",
"A.",
"",
"GES"
],
[
"Born",
"D.",
"",
"GES"
],
[
"Stornaiuolo",
"D.",
"",
"GES"
],
[
"Gambale",
"E.",
"",
"GES"
],
[
"Dalena",
"D.",
"",
"GES"
],
[
"Lucignano",
"P.",
"",
"GES"
],
[
"Jouault",
"B.",
"",
"GES"
],
[
"Lombardi",
"F.",
""
],
[
"Barone",
"A.",
""
],
[
"Altshuler",
"B. L.",
""
]
] |
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