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| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0704.3501 | Jerome Darmont | J\'er\^ome Darmont (ERIC), Fadila Bentayeb (ERIC), Omar Boussa\"id
(ERIC) | Conception d'un banc d'essais d\'ecisionnel | 20 pages | 20\`emes Journ\'ees Bases de Donn\'ees Avanc\'ees (BDA 04),
Montpellier (19/10/2004) 493-511 | null | null | cs.DB | null | We present in this paper a new benchmark for evaluating the performances of
data warehouses. Benchmarking is useful either to system users for comparing
the performances of different systems, or to system engineers for testing the
effect of various design choices. While the TPC (Transaction Processing
Performance Council) standard benchmarks address the first point, they are not
tuneable enough to address the second one. Our Data Warehouse Engineering
Benchmark (DWEB) allows to generate various ad-hoc synthetic data warehouses
and workloads. DWEB is fully parameterized. However, two levels of
parameterization keep it easy to tune. Since DWEB mainly meets engineering
benchmarking needs, it is complimentary to the TPC standard benchmarks, and not
a competitor. Finally, DWEB is implemented as a Java free software that can be
interfaced with most existing relational database management systems.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 09:13:04 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Darmont",
"Jérôme",
"",
"ERIC"
],
[
"Bentayeb",
"Fadila",
"",
"ERIC"
],
[
"Boussaïd",
"Omar",
"",
"ERIC"
]
] |
0704.3502 | Cyril Houdayer | Cyril Houdayer | Construction of type ${\rm II_1}$ factors with prescribed countable
fundamental group | 33 pages | J. reine angew Math. 634 (2009), 169-207 | null | null | math.OA math.GR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the context of Free Probability Theory, we study two different
constructions that provide new examples of factors of type ${\rm II_1}$ with
prescribed fundamental group. First we investigate state-preserving group
actions on the almost periodic free Araki-Woods factors satisfying both a
condition of mixing and a condition of free malleability in the sense of Popa.
Typical examples are given by the free Bogoliubov shifts. Take an ICC $w$-rigid
group $G$ such that $\mathcal{F}(L(G)) = \{1\}$ (e.g. $G = \Z^2 \rtimes \SL(2,
\Z)$). For any countable subgroup $S \subset \R^*_+$, we show that there exists
an action of $G$ on $L(\F_\infty)$ such that $L(\F_\infty) \rtimes G$ is a type
${\rm II_1}$ factor and its fundamental group is $S$. The second construction
is based on a free product. Take $(B(H), \psi)$ any factor of type ${\rm I}$
endowed with a faithful normal state and denote by $\Gamma \subset \R^*_+$ the
subgroup generated by the point spectrum of $\psi$. We show that the
centralizer $(L(G) \ast B(H))^{\tau \ast \psi}$ is a type ${\rm II_1}$ factor
and its fundamental group is $\Gamma$. Our proofs rely on Popa's
deformation/rigidity strategy using his intertwining-by-bimodules technique.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 19:36:47 GMT"
},
{
"version": "v2",
"created": "Mon, 31 Aug 2009 12:16:39 GMT"
}
] | 2009-08-31T00:00:00 | [
[
"Houdayer",
"Cyril",
""
]
] |
0704.3503 | Jianjun He Dr | J.J. He, A.St.J. Murphy | A consistent formalism for the Thomas-Ehrman Level Displacement | 4 pages, 2 figures and 1 table | null | null | null | nucl-th | null | Usage of the Thomas-Ehrman Level Displacement formalism has been examined.
Mistakes and inconsistencies are found in several papers, being repeated in
subsequent works. Here, we present a complete formalism with a consistent set
of definitions. Full algorithms are made available, both as a {\tt FORTRAN}
source file and as a user-friendly Visual Basic executable tool, available for
download on the World Wide Web.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 09:24:05 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"He",
"J. J.",
""
],
[
"Murphy",
"A. St. J.",
""
]
] |
0704.3504 | Berry Schoenmakers | Berry Schoenmakers, Jilles Tjoelker, Pim Tuyls and Evgeny Verbitskiy | Smooth R\'enyi Entropy of Ergodic Quantum Information Sources | 5 pages, no figures, ISIT 2007 | null | null | null | quant-ph cs.IT math.IT | null | We prove that the average smooth Renyi entropy rate will approach the entropy
rate of a stationary, ergodic information source, which is equal to the Shannon
entropy rate for a classical information source and the von Neumann entropy
rate for a quantum information source.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 09:28:58 GMT"
}
] | 2018-02-13T00:00:00 | [
[
"Schoenmakers",
"Berry",
""
],
[
"Tjoelker",
"Jilles",
""
],
[
"Tuyls",
"Pim",
""
],
[
"Verbitskiy",
"Evgeny",
""
]
] |
0704.3505 | Satoshi Moriyama | Satoshi Moriyama, Tomoko Fuse, Tomohiro Yamaguchi, and Koji Ishibashi | Spin effects in single-electron transport through carbon nanotube
quantum dots | 5pages, 5figures, accepted for publication in Phys. Rev. B | Physical Review B 76, 045102 (2007) | 10.1103/PhysRevB.76.045102 | null | cond-mat.mes-hall | null | We investigate the total spin in an individual single-wall carbon nanotube
quantum dot with various numbers of electrons in a shell by using the ratio of
the saturation currents of the first steps of Coulomb staircases for positive
and negative biases. The current ratio reflects the total-spin transition that
is increased or decreased when the dot is connected to strongly asymmetric
tunnel barriers. Our results indicate that total spin states with and without
magnetic fields can be traced by this method.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 09:35:34 GMT"
},
{
"version": "v2",
"created": "Tue, 3 Jul 2007 06:27:23 GMT"
}
] | 2012-06-22T00:00:00 | [
[
"Moriyama",
"Satoshi",
""
],
[
"Fuse",
"Tomoko",
""
],
[
"Yamaguchi",
"Tomohiro",
""
],
[
"Ishibashi",
"Koji",
""
]
] |
0704.3506 | Doron Cohen | Maya Chuchem and Doron Cohen | Counting statistics in multiple path geometries and the fluctuations of
the integrated current in a quantum stirring device | 11 pages, 2 figures, published version, Latex Eq# corrected | J. Phys. A 41, 075302 (2008) | 10.1088/1751-8113/41/7/075302 | null | quant-ph cond-mat.mes-hall | null | The amount $Q$ of particles that are transported via a path of motion is
characterized by its expectation value $<Q>$ and by its variance $Var(Q)$. We
analyze what happens if a particle has two optional paths available to get from
one site to another site, and in particular what is $Var(Q)$ for the current
which is induced in a quantum stirring device. It turns out that coherent
splitting and the stirring effect are intimately related and cannot be
understood within the framework of the prevailing probabilistic theory.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:38:09 GMT"
},
{
"version": "v2",
"created": "Fri, 31 Aug 2007 09:51:56 GMT"
},
{
"version": "v3",
"created": "Thu, 13 Dec 2007 12:27:42 GMT"
},
{
"version": "v4",
"created": "Tue, 5 Feb 2008 12:55:04 GMT"
}
] | 2008-02-05T00:00:00 | [
[
"Chuchem",
"Maya",
""
],
[
"Cohen",
"Doron",
""
]
] |
0704.3507 | Janusz Kaluzny | J. Kaluzny, S.M. Rucinski, I.B. Thompson, W. Pych, W. Krzeminski | The Clusters AgeS Experiment (CASE). I. V209 omega Cen - An Eclipsing
Post-Common Envelope Binary in the Globular Cluster omega Cen | 24 pages, 9 figures, AJ, in press | Astron.J.133:2457-2464,2007 | 10.1086/516637 | null | astro-ph | null | We use photometric and spectroscopic observations of the detached eclipsing
binary V209 omega Cen to derive the masses, radii, and luminosities of the
component stars. The system exhibits total eclipses and, based on the measured
systemic velocity and the derived distance, is a member of the globular cluster
omega Cen. We obtain 0.945 +/- 0.043 Msun, 0.983 +/- 0.015 Rsun and 6.68 +/-
0.88 Lsun for the cooler, but larger and more luminous primary component. The
secondary component has 0.144 +/- 0.008 Msun, 0.425 +/- 0.008 Rsun and 2.26 +/-
0.28 Lsun. The effective temperatures are estimated at 9370 K for the primary
and at 10866 K for the secondary. On the color-magnitude diagram of the
cluster, the primary component occupies a position between the tip of the blue
straggler region and the extended horizontal branch while the secondary
component is located close to the red border of the area occupied by hot
subdwarfs. However, its radius is too large and its effective temperature is
too low for it to be an sdB star. We propose a scenario leading to the
formation of a system with such unusual properties with the primary component
``re-born'' from a former white dwarf which accreted a new envelope through
mass transfer from its companion. The secondary star has lost most of its
envelope while starting its ascent onto the sub-giant branch. It failed to
ignite helium in its core and is currently powered by a hydrogen burning shell.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 10:55:33 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kaluzny",
"J.",
""
],
[
"Rucinski",
"S. M.",
""
],
[
"Thompson",
"I. B.",
""
],
[
"Pych",
"W.",
""
],
[
"Krzeminski",
"W.",
""
]
] |
0704.3508 | Janusz Kaluzny | J. Kaluzny, I.B. Thompson, S.M. Rucinski, W. Pych, G. Stachowski, W.
Krzeminski, G.S. Burley | The Clusters AgeS Experiment (CASE). II. The Eclipsing Blue Straggler
OGLEGC-228 in the Globular Cluster 47 Tuc | 19 pages, 5 figures, AJ, in press | Astron.J.134:541-546,2007 | 10.1086/519023 | null | astro-ph | null | We use photometric and spectroscopic observations of the eclipsing binary
OGLEGC-228 (V228) to derive the masses, radii, and luminosities of the
component stars. Based on measured systemic velocity, proper motion and
distance, the system is a blue straggler member of the globular cluster 47 Tuc.
Our analysis shows that V228 is a semi-detached Algol. We obtain M=1.512 +/-
0.022 Msun, R=1.357 +/- 0.019 Rsun, L=7.02 +/- 0.050 Lsun for the hotter and
more luminous primary component and M=0.200 +/- 0.007 Msun, R=1.238 +/- 0.013
Rsun, L=1.57 +/- 0.09 Lsun for the Roche lobe filling secondary.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 09:56:44 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kaluzny",
"J.",
""
],
[
"Thompson",
"I. B.",
""
],
[
"Rucinski",
"S. M.",
""
],
[
"Pych",
"W.",
""
],
[
"Stachowski",
"G.",
""
],
[
"Krzeminski",
"W.",
""
],
[
"Burley",
"G. S.",
""
]
] |
0704.3509 | Matteo Silimbani | Marilena Barnabei, Flavio Bonetti, and Matteo Silimbani | The descent statistic on involutions is not log-concave | 10 pages | null | null | null | math.CO | null | We establish a combinatorial connection between the sequence $(i_{n,k})$
counting the involutions on $n$ letters with $k$ descents and the sequence
$(a_{n,k})$ enumerating the semistandard Young tableaux on $n$ cells with $k$
symbols. This allows us to show that the sequences $(i_{n,k})$ are not
log-concave for some values of $n$, hence answering a conjecture due to F.
Brenti.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 10:36:32 GMT"
},
{
"version": "v2",
"created": "Fri, 20 Jul 2007 10:03:07 GMT"
},
{
"version": "v3",
"created": "Fri, 14 Mar 2008 08:55:40 GMT"
}
] | 2008-03-14T00:00:00 | [
[
"Barnabei",
"Marilena",
""
],
[
"Bonetti",
"Flavio",
""
],
[
"Silimbani",
"Matteo",
""
]
] |
0704.3510 | Junghoon Kim | Jung Hoon Kim, Jung Hoon Han | Coupling of phonons and spin waves in triangular antiferromagnet | 6 pages, 5 figures; references added, minor text revisions, submitted
to PRB | Physical Review B 76, 054431 (2007) | 10.1103/PhysRevB.76.054431 | null | cond-mat.str-el | null | We investigate the influence of the spin-phonon coupling in the triangular
antiferromagnet where the coupling is of the exchange-striction type. The
magnon dispersion is shown to be modified significantly at wave vector (2pi,0)
and its symmetry-related points, exhibiting a roton-like minimum and an
eventual instability in the dispersion. Various correlation functions such as
equal-time phonon correlation, spin-spin correlation, and local magnetization
are calculated in the presence of the coupling.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:37:32 GMT"
},
{
"version": "v2",
"created": "Mon, 2 Jul 2007 10:19:42 GMT"
}
] | 2011-11-09T00:00:00 | [
[
"Kim",
"Jung Hoon",
""
],
[
"Han",
"Jung Hoon",
""
]
] |
0704.3511 | Dirk Toeben | Steven Hurder, Dirk Toeben | Transverse LS-Category for Riemannian Foliations | null | null | null | null | math.DG | null | We study the transverse Lusternik-Schnirelmann category of a Riemannian
foliation on a compact manifold. We obtain a necessary and sufficient condition
when the transverse LS category is finite. We also introduce a variation on the
concept of transverse LS category, the essential transverse category, and show
that this is finite for every Riemannian foliation and coincides with the
transverse category if the latter is finite. Moreover we prove that the
essential transverse category is a lower bound for the number of critical leaf
closures of a basic differentiable function on M.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:55:34 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hurder",
"Steven",
""
],
[
"Toeben",
"Dirk",
""
]
] |
0704.3512 | Bobroff | J. Bobroff, S. Hebert, G. Lang, P. Mendels, D. Pelloquin, A. Maignan | Interplay between magnetic properties and thermoelectricity in misfit
and Na cobaltates | 4 pages | published in Phys. Rev. B Rapid Com Vol. 76, 100407 (R) (2007) | 10.1103/PhysRevB.76.100407 | null | cond-mat.str-el cond-mat.mtrl-sci | null | We present a comparative study of CoO2 layers in the Bi-misfit and NaxCoO2
cobaltates. Co NMR measures the intrinsic susceptibility of the Co layers and
is not affected by spurious contributions. At low dopings where
room-temperature thermopower (TEP) is large, Curie-Weiss susceptibilities are
observed in both materials. But NMR and muSR experiments find neither charge
nor spin order down to low temperatures in Bi-misfit, in contrast to the case
of NaxCoO2. This demonstrates that metallicity, charge and magnetic orders are
specific of the Na layers in NaxCoO2 whereas strong correlations are generic of
the cobaltates physics and could explain the large TEP.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:04:56 GMT"
},
{
"version": "v2",
"created": "Mon, 1 Oct 2007 13:19:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bobroff",
"J.",
""
],
[
"Hebert",
"S.",
""
],
[
"Lang",
"G.",
""
],
[
"Mendels",
"P.",
""
],
[
"Pelloquin",
"D.",
""
],
[
"Maignan",
"A.",
""
]
] |
0704.3513 | Dirk Toeben | Steven Hurder, Dirk Toeben | The Equivariant LS-Category of Polar Actions | null | null | null | null | math.DG | null | We will provide a lower bound for the equivariant Lusternik-Schnirelmann
category of an arbitrary proper action in terms of the stratification by orbit
types, and an upper bound for proper polar actions in terms of the equivariant
Lusternik-Schnirelmann category of its generalized Weyl group. As an
application we reprove a theorem of Singhof that determines the classical
Lusternik-Schnirelmann category for U(n) and SU(n).
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:15:42 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hurder",
"Steven",
""
],
[
"Toeben",
"Dirk",
""
]
] |
0704.3514 | Mikhail Danilov | M.Danilov (representing the CALICE collaboration) | Scintillator Tile Hadron Calorimeter with Novel SiPM Readout | Prepared for the Vienna Conference on Instrumentation 2007. 4 pages,
6 figures | Nucl.Instrum.Meth.A582:451-456,2007 | 10.1016/j.nima.2007.08.025 | null | physics.ins-det | null | The CALICE collaboration is presently constructing a test hadron calorimeter
(HCAL) with 7620 scintillator tiles read out by novel photo-detectors - Silicon
Photomultipliers (SiPMs). This prototype is the first device which uses SiPMs
on a large scale. We present the design of the HCAL and report on measured
properties of more than 10 thousand SiPMs. We discuss the SiPM efficiency,
gain, cross-talk, and noise rate dependence on bias voltage and temperature,
including the spread in these parameters. We analyze the reasons for SiPM
rejection and present the results of the long term stability studies. The first
measurements of the SiPM radiation hardness are presented. We compare
properties of SiPM with the properties of similar devices, MRS APD and MPPC. A
possibility to make the tiles thinner and to read them out without WLS fibers
has been studied.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:29:02 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Danilov",
"M.",
"",
"representing the CALICE collaboration"
]
] |
0704.3515 | Jegor Uglov Mr | J. Uglov, V. Schetinin, C. Maple | Comparing Robustness of Pairwise and Multiclass Neural-Network Systems
for Face Recognition | null | null | 10.1155/2008/468693 | null | cs.AI | null | Noise, corruptions and variations in face images can seriously hurt the
performance of face recognition systems. To make such systems robust,
multiclass neuralnetwork classifiers capable of learning from noisy data have
been suggested. However on large face data sets such systems cannot provide the
robustness at a high level. In this paper we explore a pairwise neural-network
system as an alternative approach to improving the robustness of face
recognition. In our experiments this approach is shown to outperform the
multiclass neural-network system in terms of the predictive accuracy on the
face images corrupted by noise.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:29:19 GMT"
}
] | 2016-02-17T00:00:00 | [
[
"Uglov",
"J.",
""
],
[
"Schetinin",
"V.",
""
],
[
"Maple",
"C.",
""
]
] |
0704.3516 | Marcel van Kessel | M.T.M. van Kessel | Cancelling Quadratic Divergences Without Supersymmetry | 19 pages | Nucl.Phys.B800:330-348,2008 | 10.1016/j.nuclphysb.2008.03.018 | null | hep-th | null | We construct a theory which has the same particle content as softly broken
minimal supersymmetric QED (MSQED) and is free of quadratic divergences up to
two loops. Also this theory is completely gauge invariant. It appears that
MSQED is not at all the only theory without these quadratic divergences. This
proves that there exist non supersymmetric theories in which there are no
quadratic divergences up to two loops.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:31:34 GMT"
},
{
"version": "v2",
"created": "Fri, 2 Nov 2007 10:19:52 GMT"
},
{
"version": "v3",
"created": "Tue, 18 Mar 2008 14:39:34 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"van Kessel",
"M. T. M.",
""
]
] |
0704.3517 | Wlodek Bednarek | W. Bednarek | Gamma-ray production in young open clusters: Berk 87, Cyg OB2 and
Westerlund 2 | 12 pages, 7 figures, accepted to MNRAS | Mon.Not.Roy.Astron.Soc.382:367,2007 | 10.1111/j.1365-2966.2007.12373.x | null | astro-ph | null | Young open clusters are likely sites of cosmic ray acceleration as indicated
by recent detections of the TeV gamma-ray sources in the directions of two open
clusters (Cyg OB2 and Westerlund 2) and their directional proximity to some
unidentified EGRET sources. In fact, up to now a few different scenarios for
acceleration of particles inside open clusters have been considered, i.e.
shocks in massive star winds, pulsars and their nebulae, supernova shocks,
massive compact binaries. Here we consider in detail the radiation processes
due to both electrons and hadrons accelerated inside the open cluster. As a
specific scenario, we apply the acceleration process at the shocks arising in
the winds of WR type stars. Particles diffuse through the medium of the open
cluster during the activity time of the acceleration scenario defined by the
age of the WR star. They interact with the matter and radiation, at first
inside the open cluster and, later in the dense surrounding clouds. We
calculate the broad band spectrum in different processes for three example open
clusters (Berk 87, Cyg OB2, Westerlund 2) for which the best observational
constraints on the spectra are at present available. It is assumed that the
high energy phenomena, observed from the X-ray up to the GeV-TeV gamma-ray
energies, are related to each other. We conclude that the most likely
description of the radiation processes in these objects is achieved in the
hybrid (leptonic-hadronic) model in which leptons are responsible for the
observed X-ray and GeV gamma-ray emission and hadrons are responsible for the
TeV gamma-ray emission, which is produced directly inside and in dense clouds
surrounding the open cluster.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:34:54 GMT"
},
{
"version": "v2",
"created": "Mon, 20 Aug 2007 13:34:14 GMT"
}
] | 2013-06-21T00:00:00 | [
[
"Bednarek",
"W.",
""
]
] |
0704.3518 | Lorenzo Calibbi | L. Calibbi, Y. Mambrini, S. K. Vempati | SUSY-GUTs, SUSY-Seesaw and the Neutralino Dark Matter | 18 pages, 7 figures; references added, figure added, improved
discussions in text, to appear in JHEP | JHEP 0709:081,2007 | 10.1088/1126-6708/2007/09/081 | null | hep-ph astro-ph | null | We will consider a SUSY-SU(5) with one right-handed neutrino with a large top
like Yukawa coupling. Assuming universal soft masses at high scale we compute
the low-energy spectrum and subsequently the neutralino LSP relic density
taking also into consideration SU(5) as well as the see-saw running effects
above the gauge coupling unification scale. We found that there exists no
viable region in parameter space for $\tan\beta \ler ~35$. The $\tilde{\tau}$
coannihilation process starts becoming efficient for $\tan\beta \ger 35-40$.
However, this process is significantly constrained by the limited range in
which the stau is lighter than the neutralino. In fact, for a given $\tan\beta$
we find that there exists an upper bound on the lightest neutralino mass
($M_{\chi_1^0}$) in this region. The A-pole funnel region appears at very large
$\tan\beta \simeq 45-50$, while the focus-point region does not make an
appearance till large ($m_0,M_{1/2}$), namely a few TeV. Large $A_0$ terms at
high scale can lead to extended regions consistent with WMAP constraints and
remove the upper bounds in the stau coannihilation regions.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:39:08 GMT"
},
{
"version": "v2",
"created": "Mon, 17 Sep 2007 09:56:30 GMT"
}
] | 2009-01-06T00:00:00 | [
[
"Calibbi",
"L.",
""
],
[
"Mambrini",
"Y.",
""
],
[
"Vempati",
"S. K.",
""
]
] |
0704.3519 | Thomas Simon | Aim\'e Lachal (ICJ, DP), Thomas Simon (ICJ, DP) | Chung's law for homogeneous Brownian functionals | Revised version, to appear in the Rocky Mountain Journal of
Mathematics | null | null | null | math.PR | null | Consider the first exit time $T_{a,b}$ from a finite interval $[-a,b]$ for an
homogeneous fluctuating functional $X$ of a linear Brownian motion. We show the
existence of a finite positive constant $\k$ such that
$$\lim_{t\to\infty}t^{-1}\log \p[ T_{ab} > t] = -\k.$$ Following Chung's
original approach, we deduce a "liminf" law of the iterated logarithm for the
two-sided supremum of $X$. This extends and gives a new point of view on a
result of Khoshnevisan and Shi.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:46:09 GMT"
},
{
"version": "v2",
"created": "Tue, 23 Oct 2007 15:50:04 GMT"
}
] | 2007-10-23T00:00:00 | [
[
"Lachal",
"Aimé",
"",
"ICJ, DP"
],
[
"Simon",
"Thomas",
"",
"ICJ, DP"
]
] |
0704.3520 | Jerome Darmont | Kamel Aouiche (ERIC), J\'er\^ome Darmont (ERIC) | Vers l'auto-administration des entrep\^ots de donn\'ees | Version courte de 4 pages | XXXV\`emes Journ\'ees de Statistique, Session sp\'eciale
Entreposage et Fouille de Donn\'ees, Lyon (02/06/2003) 105-108 | null | null | cs.DB | null | With the wide development of databases in general and data warehouses in
particular, it is important to reduce the tasks that a database administrator
must perform manually. The idea of using data mining techniques to extract
useful knowledge for administration from the data themselves has existed for
some years. However, little research has been achieved. The aim of this study
is to search for a way of extracting useful knowledge from stored data to
automatically apply performance optimization techniques, and more particularly
indexing techniques. We have designed a tool that extracts frequent itemsets
from a given workload to compute an index configuration that helps optimizing
data access time. The experiments we performed showed that the index
configurations generated by our tool allowed performance gains of 15% to 25% on
a test database and a test data warehouse.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:47:35 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Aouiche",
"Kamel",
"",
"ERIC"
],
[
"Darmont",
"Jérôme",
"",
"ERIC"
]
] |
0704.3521 | You-gang Feng | You-gang Feng | Duality of momentum-energy and space-time on an almost complex manifold | 12pages | null | null | null | physics.gen-ph | null | We proved that under quantum mechanics a momentum-energy and a space-time are
dual vector spaces on an almost complex manifold in position representation,
and the minimal uncertainty relations are equivalent to the inner-product
relations of their bases. In a microscopic sense, there exist locally a
momentum-energy conservation and a space-time conservation. The minimal
uncertainty relations refer to a local equilibrium state for a stable system,
and the relations will be invariable in the special relativity. A supposition
about something having dark property is proposed, which relates to a breakdown
of time symmetry.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 11:58:56 GMT"
}
] | 2007-09-03T00:00:00 | [
[
"Feng",
"You-gang",
""
]
] |
0704.3522 | Aharon Gero | A. Gero and E. Akkermans | Superradiance and multiple scattering of photons in atomic gases | 12 pages, 7 figures | Phys. Rev. A 75, 053413 (2007) | 10.1103/PhysRevA.75.053413 | null | cond-mat.mes-hall | null | We study the influence of cooperative effects such as superradiance and
subradiance, on the scattering properties of dilute atomic gases. We show that
cooperative effects lead to an effective potential between pairs of atoms that
decays like $1/r$. In the case of superradiance, this potential is attractive
for close enough atoms and can be interpreted as a coherent mesoscopic effect.
We consider a model of multiple scattering of a photon among superradiant pairs
and calculate the elastic mean free path and the group velocity. We study first
the case of a scalar wave which allows to obtain and to understand basic
features of cooperative effects and multiple scattering. We then turn to the
general problem of a vector wave. In both cases, we obtain qualitatively
similar results and derive, for the case of a scalar wave, analytic expressions
of the elastic mean free path and of the group velocity for an arbitrary (near
resonance) detuning.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:07:32 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Gero",
"A.",
""
],
[
"Akkermans",
"E.",
""
]
] |
0704.3523 | Aleksandra Nowel | Iwona Karolkiewicz, Aleksandra Nowel, Zbigniew Szafraniec | Immersions of spheres and algebraically constructible functions | 17 pages | null | null | null | math.AG | null | Let L be an algebraic set and let g : R^(n+1) \times L --> R^(2n) (n is even)
be a polynomial mapping such that for each l in L there is r(l)>0 such that the
mapping g_l = g(.,l) restricted to the sphere S^n(r) is an immersion for every
0<r<(l), so that the intersection number I(g_l|S^n(r)) is defined. Then the
function which maps l in L to I(g_l|S^n(r)) is algebraically constructible.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:21:23 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Karolkiewicz",
"Iwona",
""
],
[
"Nowel",
"Aleksandra",
""
],
[
"Szafraniec",
"Zbigniew",
""
]
] |
0704.3524 | Richard White Mr. | R J White, H J Rose, S M Bradbury, P Marshall | Parallel Distribution of Asynchronous Optical Signals | 14 pages, 5 figures | Nucl.Instrum.Meth.A577:708-714,2007 | 10.1016/j.nima.2007.04.138 | null | astro-ph | null | An eleven channel digital asynchronous transceiver (DAT) employing parallel
optical link technology has been developed for trigger signal distribution
across the Very Energetic Radiation Imaging Telescope Array System (VERITAS).
Combinatorial logic functions are implemented in Xilinx Spartan 3 FPGAs,
providing a versatile solution adaptable for use in future atmospheric Cerenkov
detectors and other high-energy astroparticle experiments. The device is
dead-time free and introduces a minimal skew of 1.6 ns between channels. The
jitter on each DAT channel is less than 0.8 ns 95% of the time, allowing
communication between telescopes and a central trigger system separated by
hundreds of meters, without limiting array performance.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:35:10 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"White",
"R J",
""
],
[
"Rose",
"H J",
""
],
[
"Bradbury",
"S M",
""
],
[
"Marshall",
"P",
""
]
] |
0704.3525 | Uzy Smilansky | Uzy Smilansky | Quantum chaos on discrete graphs | null | null | null | null | math-ph math.MP | null | Adapting a method developed for the study of quantum chaos on {\it quantum
(metric)} graphs \cite {KS}, spectral $\zeta$ functions and trace formulae for
{\it discrete} Laplacians on graphs are derived. This is achieved by expressing
the spectral secular equation in terms of the periodic orbits of the graph, and
obtaining functions which belongs to the class of $\zeta$ functions proposed
originally by Ihara \cite {Ihara}, and expanded by subsequent authors \cite
{Stark,Sunada}. Finally, a model of "classical dynamics" on the discrete graph
is proposed. It is analogous to the corresponding classical dynamics derived
for quantum graphs \cite {KS}.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:24:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Smilansky",
"Uzy",
""
]
] |
0704.3526 | Nikolai Zhigadlo | J. Karpinski, N. Zhigadlo, S. Katrych, B. Batlogg, M. Tortello, K.
Rogacki, R. Puzniak | MgB2 single crystals substituted with Li and with Li-C: Structural and
superconducting properties | 22 pages, 17 figures, submitted to PRB | Phys. Rev. B 77, 214507 (2008) | 10.1103/PhysRevB.77.214507 | null | cond-mat.supr-con cond-mat.mtrl-sci | null | The effect of Li substitution for Mg and of Li-C co-substitution on the
superconducting properties and crystal structure of MgB2 single crystals has
been investigated. It has been found that hole doping with Li decreases the
superconducting transition temperature Tc, but at a slower rate than electron
doping with C or Al. Tc of MgB2 crystals with simultaneously substituted Li for
Mg and C for B decreases more than in the case where C is substituted alone.
This means that holes introduced by Li cannot counterbalance the effect of
decrease of Tc caused by introduction of electrons coming from C. The possible
reason of it can be that holes coming from Li occupy the pi band while
electrons coming from C fill the sigma band. The temperature dependences of the
upper critical field Hc2 for Al and Li substituted crystals with the same Tc
show a similar dHc2/dT slope at Tc and a similar Hc2(T) behavior, despite of
much different substitution level. This indicates that the mechanism
controlling Hc2 and Tc is similar in both hole and electron doped crystals.
Electrical transport measurements show an increase of resistivity both in Li
substituted crystals and in Li and C co-substituted crystals. This indicates
enhanced scattering due to defects introduced by substitutions including
distortion of the lattice. The observed behavior can be explained as a result
of two effects, influencing both Tc and Hc2. The first one is doping related to
the changes in the carrier concentration, which may lead to the decrease or to
the increase of Tc. The second one is related to the introduction of new
scattering centers leading to the modification of the interband and/or
intraband scattering and therefore, to changes in the superconducting gaps and
to the reduction of Tc.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:30:39 GMT"
}
] | 2008-10-16T00:00:00 | [
[
"Karpinski",
"J.",
""
],
[
"Zhigadlo",
"N.",
""
],
[
"Katrych",
"S.",
""
],
[
"Batlogg",
"B.",
""
],
[
"Tortello",
"M.",
""
],
[
"Rogacki",
"K.",
""
],
[
"Puzniak",
"R.",
""
]
] |
0704.3527 | Fabio Cipriani | Fabio Cipriani, Gabriele Grillo | Hypercontractivity, Nash inequalities, and subordination for classes of
nonlinear semigroups | 19 pages | Semigroup Forum 78 (2009), no. 1 | null | null | math.FA | null | A suitable notion of hypercontractivity for a nonlinear semigroup $\{T_t\}$
is shown to imply Gagliardo--Nirenberg inequalities for its generator $H$,
provided a subhomogeneity property holds for the energy functional $(u,Hu)$. We
use this fact to prove that, for semigroups generated by operators of
$p$--Laplacian--type, hypercontractivity implies ultracontractivity. We then
introduce the notion of subordinated nonlinear semigroups when the
corresponding Bernstein function is $f(x)=x^\alpha$, and write down an explicit
formula for the associated generator. It is shown that, in certain cases,
hypercontractivity still holds for the subordinated semigroup and, hence, that
Nash--type inequalities holds as well for the subordinated generator.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:33:07 GMT"
},
{
"version": "v2",
"created": "Wed, 30 Apr 2008 14:45:27 GMT"
}
] | 2021-06-01T00:00:00 | [
[
"Cipriani",
"Fabio",
""
],
[
"Grillo",
"Gabriele",
""
]
] |
0704.3528 | Norberto Castro Rodriguez | A. Herrero | Spectroscopic Analyses of Massive Blue Stars (Galactic or Extragalactic) | 7 pages, 5 figures, conference proceedings | null | null | null | astro-ph | null | We review recent advances in our understanding of massive stars through the
analysis of their spectra. Improvements in model atmospheres and analysis
methods are briefly discussed. Results obtained for stars in the Local Group
are compared and the present status of different open questions, like the
temperature scale of OB stars, the Wind Momentum-Luminosity Relation or the
stellar rotation, is outlined.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:24:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Herrero",
"A.",
""
]
] |
0704.3529 | Hellmut Baumgaertel | Hellmut Baumgaertel | Remarks related to the paper of Rafael de la Madrid: "On the
inconsistency of the Bohm-Gadella theory with quantum mechanics", JPhysA 39,
No. 29, 9255-9268 (2006) | 4 pages | null | null | null | math-ph math.MP | null | The paper contains critical comments to the paper mentioned in the title from
the mathematical point of view
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:49:14 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Baumgaertel",
"Hellmut",
""
]
] |
0704.3530 | Diego Conti | Diego Conti | Invariant forms, associated bundles and Calabi-Yau metrics | 36 pages. v2: changed title, added new examples in 7.2 | Journal of Geometry and Physics N. 57 (12), 2007, pp. 2483-2508 | 10.1016/j.geomphys.2007.08.010 | null | math.DG | null | We develop a method, initially due to Salamon, to compute the space of
``invariant'' forms on an associated bundle X=P\times_G V, with a suitable
notion of invariance. We determine sufficient conditions for this space to be
d-closed. We apply our method to the construction of Calabi-Yau metrics on
TCP^1 and TCP^2.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:33:09 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Oct 2007 14:49:08 GMT"
}
] | 2007-11-12T00:00:00 | [
[
"Conti",
"Diego",
""
]
] |
0704.3531 | Roman Mizuk | M. Danilov and R. Mizuk | Experimental Review on Pentaquarks | Update of the review given at the ITEP Winter School of Physics and
at the 19th Rencontres de Physique de la Vallee d'Aoste: Results and
Perspectives in Particle Physics, La Thuile, Aosta Valley, Italy, 27 Feb - 5
Mar 2005. 25 pages, 15 figures. Discussion of new DIANA results is corrected
and supplemented | null | 10.1134/S1063778808040029 | ITEP-06-07 | hep-ex | null | The experimental evidence for pentaquarks is reviewed and compared with the
experiments that do not see any sign of pentaquarks. This paper is based on a
lecture given at the 33rd ITEP Winter School of Physics in the beginning of
2005. Results obtained since then are summarized in the epilogue.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 12:58:59 GMT"
},
{
"version": "v2",
"created": "Tue, 24 Jul 2007 14:20:06 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Danilov",
"M.",
""
],
[
"Mizuk",
"R.",
""
]
] |
0704.3532 | Guohuai Zhu | Mingxing Luo, Guohuai Zhu | Some Phenomenologies of Unparticle Physics | Version to appear in Phys. Letts. B. 9 pages, 3 figures | Phys.Lett.B659:341-344,2008 | 10.1016/j.physletb.2007.10.058 | null | hep-ph hep-th | null | Fermionic unparticles are introduced and their basic properties are
discussed. Some phenomenologies related are exploited, such as their effects on
charged Higgs boson decays and anomalous magnetic moments of leptons. Also, it
has been found that measurements of $B^0-\bar B^0$ mixing could yield
interesting constraints on couplings between unparticle operators and standard
model fields.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:19:33 GMT"
},
{
"version": "v2",
"created": "Tue, 15 May 2007 02:00:42 GMT"
},
{
"version": "v3",
"created": "Thu, 3 Jan 2008 02:38:01 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Luo",
"Mingxing",
""
],
[
"Zhu",
"Guohuai",
""
]
] |
0704.3533 | Thoudam Satyendra mr | S. V. Godambe (a), R. C. Rannot (a), K. S. Baliyan (b), A. K. Tickoo
(a), S. Thoudam (a), V. K. Dhar (a), P. Chandra (a), K. K. Yadav (a), K.
Venugopal (a), N. Bhatt (a), S. Bhattacharyya (a), K. Chanchalani (a),
S.Ganesh (a), H. C. Goyal (a), U. C. Joshi (b), R. K. Kaul (a), M. Kothari
(a), S. Kotwal (a), M.K. Koul (a), R. Koul (a), S. Sahaynathan (a), C. Shah
(b), M. Sharma (a) ((a) Astrophysical Sciences Division, Bhabha Atomic
Research Centre, Trombay, Mumbai, India (b) Physical Research Laboratory,
Ahmedabad, India) | Very High Energy $\gamma$-ray and Near Infrared observations of
1ES2344+514 during 2004-05 | 15 pages, 6 figures, 4 tables, accepted for publication in Journal of
Physics G | J.Phys.G34:1683-1696,2007 | 10.1088/0954-3899/34/7/009 | null | astro-ph | null | We have observed the BL Lac object 1ES2344+514 (z = 0.044) in Very High
Energy (VHE) gamma-ray and near-infrared wavelength bands with TACTIC and MIRO
telescopes respectively. The observations were made from 18th October to 9th
December 2004 and 27th October 2005 to 1st January 2006. Detailed analysis of
the TACTIC data indicates absence of a statistically significant gamma-ray
signal both in overall data and on a nightly basis from the source direction.
We estimate an upper limit of I($\geq$1.5 TeV)$\leq 3.84 \times 10^{-12}$
photons cm$^{-2}$ s$^{-1}$ at a 3$\sigma$ confidence level on the integrated
$\gamma$-ray flux. In addition, we have also compared TACTIC TeV light curves
with those of the RXTE ASM (2-12keV) for the contemporary period and find that
there are no statistically significant increases in the signal strengths from
the source in both these energy regions. During 2004 IR observations,
1ES2344+514 shows low level (~0.06 magnitude) day-to-day variation in both, J &
H bands. However, during 2005 observation epoch, the source brightens up by
about 0.41 magnitude from its October 2005 level J magnitude= 12.64 to J =
12.23 on December 6, 2005. It then fades by about 0.2 magnitude during 6 to 10
December, 2005. The variation is seen in both, J & H, bands simultaneously. The
light travel time arguments suggest that the emission region size is of the
order of $10^{17}$ cms.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:04:16 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Godambe",
"S. V.",
"",
"a"
],
[
"Rannot",
"R. C.",
"",
"a"
],
[
"Baliyan",
"K. S.",
"",
"b"
],
[
"Tickoo",
"A. K.",
"",
"a"
],
[
"Thoudam",
"S.",
"",
"a"
],
[
"Dhar",
"V. K.",
"",
"a"
],
[
"Chandra",
"P.",
"",
"a"
],
[
"Yadav",
"K. K.",
"",
"a"
],
[
"Venugopal",
"K.",
"",
"a"
],
[
"Bhatt",
"N.",
"",
"a"
],
[
"Bhattacharyya",
"S.",
"",
"a"
],
[
"Chanchalani",
"K.",
"",
"a"
],
[
"Ganesh",
"S.",
"",
"a"
],
[
"Goyal",
"H. C.",
"",
"a"
],
[
"Joshi",
"U. C.",
"",
"b"
],
[
"Kaul",
"R. K.",
"",
"a"
],
[
"Kothari",
"M.",
"",
"a"
],
[
"Kotwal",
"S.",
"",
"a"
],
[
"Koul",
"M. K.",
"",
"a"
],
[
"Koul",
"R.",
"",
"a"
],
[
"Sahaynathan",
"S.",
"",
"a"
],
[
"Shah",
"C.",
"",
"b"
],
[
"Sharma",
"M.",
"",
"a"
]
] |
0704.3534 | Rennan Barkana | Rennan Barkana (Tel Aviv University) | On Correlated Random Walks and 21-cm Fluctuations During Cosmic
Reionization | 10 pages, 4 figures, published in MNRAS | Mon.Not.Roy.Astron.Soc.376:1784-1792,2007 | 10.1111/j.1365-2966.2007.11569.x | null | astro-ph | null | Analytical approaches to galaxy formation and reionization are based on the
mathematical problem of random walks with barriers. The statistics of a single
random walk can be used to calculate one-point distributions ranging from the
mass function of virialized halos to the distribution of ionized bubble sizes
during reionization. However, an analytical calculation of two-point
correlation functions or of spatially-dependent feedback processes requires the
joint statistics of random walks at two different points. An accurate
analytical expression for the statistics of two correlated random walks has
been previously found only for the case of a constant barrier height. However,
calculating bubble sizes or accurate statistics for halo formation involves
more general barriers that can often be approximated as linear barriers. We
generalize the two-point solution with constant barriers to linear barriers,
and apply it as an illustration to calculate the correlation function of
cosmological 21-cm fluctuations during reionization.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:04:31 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Barkana",
"Rennan",
"",
"Tel Aviv University"
]
] |
0704.3535 | Lutz Petersen | Lutz Petersen | Quantum Simulations in Ion Traps -- Towards Simulating the Early
Expanding Universe | diploma thesis; 154 pages, 79 figures; v2: added references for
introduction | null | null | null | quant-ph | null | This thesis provides an overview of an approach to quantum simulations using
magnesium-25 ions stored in a linear Paul trap as the carriers of quantum
information. Their quantum state is manipulated and read out using ultraviolet
laser beams. Several important steps towards realising the first experiments
have been undertaken, the most striking of which is cooling the ions to their
motional ground state. We describe a first experiment simulating cosmological
particle creation in the Early Universe and discuss the expected results.
| [
{
"version": "v1",
"created": "Wed, 25 Apr 2007 21:53:30 GMT"
},
{
"version": "v2",
"created": "Mon, 7 May 2007 14:14:12 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Petersen",
"Lutz",
""
]
] |
0704.3536 | Carlos Galindo | C. Galindo and F.Monserrat | $\delta$-sequences and Evaluation Codes defined by Plane Valuations at
Infinity | null | null | null | null | cs.IT math.IT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We introduce the concept of $\delta$-sequence. A $\delta$-sequence $\Delta$
generates a well-ordered semigroup $S$ in $\mathbb{Z}^2$ or $\mathbb{R}$. We
show how to construct (and compute parameters) for the dual code of any
evaluation code associated with a weight function defined by $\Delta$ from the
polynomial ring in two indeterminates to a semigroup $S$ as above. We prove
that this is a simple procedure which can be understood by considering a
particular class of valuations of function fields of surfaces, called plane
valuations at infinity. We also give algorithms to construct an unlimited
number of $\delta$-sequences of the different existing types, and so this paper
provides the tools to know and use a new large set of codes.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:18:53 GMT"
},
{
"version": "v2",
"created": "Mon, 14 Jul 2008 09:17:57 GMT"
}
] | 2008-07-14T00:00:00 | [
[
"Galindo",
"C.",
""
],
[
"Monserrat",
"F.",
""
]
] |
0704.3537 | Antoni Szczurek | Antoni Szczurek, Anna Rybarska and Gabriela Slipek | Dijet correlations at RHIC, leading-order $k_t$-factorization approach
versus next-to-leading order collinear approach | 26 pages, 17 figures | Phys.Rev.D76:034001,2007 | 10.1103/PhysRevD.76.034001 | null | hep-ph | null | We compare results of $k_t$-factorization approach and next-to-leading order
collinear-factorization approach for dijet correlations in proton-proton
collisions at RHIC energies. We discuss correlations in azimuthal angle as well
as correlations in two-dimensional space of transverse momenta of two jets.
Some $k_t$-factorization subprocesses are included for the first time in the
literature. Different unintegrated gluon/parton distributions are used in the
$k_t$-factorization approach. The results depend on UGDF/UPDF used. For
collinear NLO case the situation depends significantly on whether we consider
correlations of any two jets or correlations of leading jets only. In the first
case the $2 \to 2$ contributions associated with soft radiations summed up in
the $k_t$-factorization approach dominate at $\phi \sim \pi$ and at equal
moduli of jet transverse momenta. The collinear NLO $2 \to 3$ contributions
dominate over $k_t$-factorization cross section at small relative azimuthal
angles as well as for asymmetric transverse momentum configurations. In the
second case the NLO contributions vanish at small relative azimuthal angles
and/or large jet transverse-momentum disbalance due to simple kinematical
constraints. There are no such limitations for the $k_t$-factorization
approach. All this makes the two approaches rather complementary. The role of
several cuts is discussed and quantified.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:23:43 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Szczurek",
"Antoni",
""
],
[
"Rybarska",
"Anna",
""
],
[
"Slipek",
"Gabriela",
""
]
] |
0704.3538 | Yasushi Watanabe | T. Mori, et al (for the Belle Collaboration) | High statistics measurement of the cross sections of gamma gamma -> pi^+
pi^- production | 20pages, 11 fig | J.Phys.Soc.Jap.76:074102,2007 | 10.1143/JPSJ.76.074102 | null | hep-ex | null | We report on a high statistics measurement of the total and differential
cross sections of the process gamma gamma -> pi^+ pi^- in the pi^+ pi^-
invariant mass range 0.8 GeV/c^2 < W < 1.5 GeV/c^2 with 85.9 fb^{-1} of data
collected at sqrt{s}=10.58 GeV and 10.52 GeV with the Belle detector. A clear
signal of the f_0(980) resonance is observed in addition to the f_2(1270)
resonance. An improved 90% confidence level upper limit Br.(eta'(958) -> pi^+
pi^-) < 2.9 x 10^{-3} is obtained for P- and CP-violating decay of the
eta'(958) meson using the most conservative assumption about the interference
with the background.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 07:35:39 GMT"
}
] | 2019-08-12T00:00:00 | [
[
"Mori",
"T.",
""
]
] |
0704.3539 | Pavol Schwartz | P. Schwartz (1), B. Schmieder (2), P. Heinzel (1) ((1) Astronomical
Institute AS, Ondrejov, Czech Republic, (2) Observatoire de Paris, Section
Meudon, LESIA, Meudon, France) | Non-LTE Analysis of Lyman-Line Observations of a Filament with SUMER | In press,"Physics of Chromospheric Plasmas" (Coimbra), ASP 368, 359
(2007) | null | null | null | astro-ph | null | We present non-LTE diagnostics of the filament observed by SOHO/SUMER on May
27, 2005 in the whole Lyman series. The filament was situated close to the disk
center. The Ly_alpha observations were carried out with normal voltage of
detector A. The slit was placed at the central part of the detector -- outside
the Ly_alpha attenuator. Therefore, the observed profiles of this line could be
calibrated reliably.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:44:50 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Schwartz",
"P.",
""
],
[
"Schmieder",
"B.",
""
],
[
"Heinzel",
"P.",
""
]
] |
0704.3540 | Jerome Martin | Jerome Martin | Inflationary Perturbations: the Cosmological Schwinger Effect | 49 pages, 6 figures, to appear in a LNP volume "Inflationary
Cosmology" | Lect.NotesPhys.738:193-241,2008 | 10.1007/978-3-540-74353-8_6 | null | hep-th astro-ph gr-qc hep-ph | null | This pedagogical review aims at presenting the fundamental aspects of the
theory of inflationary cosmological perturbations of quantum-mechanical origin.
The analogy with the well-known Schwinger effect is discussed in detail and a
systematic comparison of the two physical phenomena is carried out. In
particular, it is demonstrated that the two underlying formalisms differ only
up to an irrelevant canonical transformation. Hence, the basic physical
mechanisms at play are similar in both cases and can be reduced to the
quantization of a parametric oscillator leading to particle creation due to the
interaction with a classical source: pair production in vacuum is therefore
equivalent to the appearance of a growing mode for the cosmological
fluctuations. The only difference lies in the nature of the source: an electric
field in the case of the Schwinger effect and the gravitational field in the
case of inflationary perturbations. Although, in the laboratory, it is
notoriously difficult to produce an electric field such that pairs extracted
from the vacuum can be detected, the gravitational field in the early universe
can be strong enough to lead to observable effects that ultimately reveal
themselves as temperature fluctuations in the Cosmic Microwave Background.
Finally, the question of how quantum cosmological perturbations can be
considered as classical is discussed at the end of the article.
| [
{
"version": "v1",
"created": "Tue, 24 Apr 2007 11:06:46 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Martin",
"Jerome",
""
]
] |
0704.3541 | Sangam Banerjee Dr | S. Banerjee, K. Rajendran, N. Gayathri, M. Sardar, S. Senthilkumar and
V. Sengodan | Change in the room temperature magnetic property of ZnO upon Mn doping | 5 figures | null | 10.1063/1.2969945 | null | cond-mat.mtrl-sci | null | We present in this paper the changes in the room temperature magnetic
property of ZnO on Mn doping prepared using solvo-thermal process. The zero
field cooled (ZFC) and field cooled (FC) magnetisation of undoped ZnO showed
bifurcation and magnetic hysteresis at room temperature. Upon Mn doping the
magnetic hysteresis at room temperature and the bifurcation in ZFC-FC
magnetization vanishes. The results seem to indicate that undoped ZnO is
ferromagnetic while on the other hand the Mn doped ZnO is not a ferromagnetic
system. We observe that on addition of Mn atoms the system shows
antiferromagnetism with very giant magnetic moments.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:55:17 GMT"
},
{
"version": "v2",
"created": "Fri, 28 Sep 2007 12:54:59 GMT"
},
{
"version": "v3",
"created": "Tue, 15 Apr 2008 08:04:09 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Banerjee",
"S.",
""
],
[
"Rajendran",
"K.",
""
],
[
"Gayathri",
"N.",
""
],
[
"Sardar",
"M.",
""
],
[
"Senthilkumar",
"S.",
""
],
[
"Sengodan",
"V.",
""
]
] |
0704.3542 | Paul Zinn-Justin | A. V. Razumov, Yu. G. Stroganov and P. Zinn-Justin | Polynomial solutions of qKZ equation and ground state of XXZ spin chain
at Delta = -1/2 | v2: cosmetic changes, new section on refined TSSCPPs vs refined ASMs | null | 10.1088/1751-8113/40/39/009 | null | math-ph math.CO math.MP nlin.SI | null | Integral formulae for polynomial solutions of the quantum
Knizhnik-Zamolodchikov equations associated with the R-matrix of the six-vertex
model are considered. It is proved that when the deformation parameter q is
equal to e^{+- 2 pi i/3} and the number of vertical lines of the lattice is
odd, the solution under consideration is an eigenvector of the inhomogeneous
transfer matrix of the six-vertex model. In the homogeneous limit it is a
ground state eigenvector of the antiferromagnetic XXZ spin chain with the
anisotropy parameter Delta equal to -1/2 and odd number of sites. The obtained
integral representations for the components of this eigenvector allow to prove
some conjectures on its properties formulated earlier. A new statement relating
the ground state components of XXZ spin chains and Temperley-Lieb loop models
is formulated and proved.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:44:59 GMT"
},
{
"version": "v2",
"created": "Thu, 9 Aug 2007 14:46:44 GMT"
},
{
"version": "v3",
"created": "Mon, 1 Oct 2007 14:48:30 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Razumov",
"A. V.",
""
],
[
"Stroganov",
"Yu. G.",
""
],
[
"Zinn-Justin",
"P.",
""
]
] |
0704.3543 | Rita Bernabei | R. Bernabei (Univ. and INFN Roma Tor Vergata) | Results on Dark Matter and beta beta decay modes by DAMA at Gran Sasso | Contributed paper to Neutrinoless Double Beta Decay (NDBD07),
Ahmedabad (India), February 2007 | null | null | null | astro-ph hep-ex | null | DAMA is an observatory for rare processes and it is operative deep
underground at the Gran Sasso National Laboratory of the I.N.F.N. (LNGS). Here
some arguments will be presented on the investigation on dark matter particles
by annual modulation signature and on some of the realized double beta decay
searches.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:47:58 GMT"
},
{
"version": "v2",
"created": "Mon, 21 May 2007 09:11:55 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bernabei",
"R.",
"",
"Univ. and INFN Roma Tor Vergata"
]
] |
0704.3544 | Christoph Sieg | Christoph Sieg | Holographic flavour in the N=1 Polchinski-Strassler background | LaTeX, 46 pages, 6 figures, 2 tables | JHEP0708:031,2007 | 10.1088/1126-6708/2007/08/031 | IFUM-891-FT | hep-th | null | To endow the N=1* SYM theory with quarks, we embed D7-brane probes into its
gravity dual, known as the Polchinski-Strassler background. The non-vanishing
3-form flux G_3 in the background is dual to mass terms for the three adjoint
chiral superfields, deforming the N=4 SYM theory to the N=1* SYM theory. We
keep its three mass parameters independent. This generalizes our analysis in
hep-th/0610276 for the N=2* SYM theory. We work at second order in the mass
perturbation, i.e. G_3 and its backreaction on the background are considered
perturbatively up to this order. We find analytic solutions for the embeddings
which in general depend also on angular variables. We discuss the properties of
the solutions and give error estimates on our approximation. By applying the
method of holographic renormalization, we show that in all cases the embeddings
are at least consistent with supersymmetry.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:21:32 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Sieg",
"Christoph",
""
]
] |
0704.3545 | Renyue Cen | Renyue Cen and Mario A. Riquelme (Princeton University Observatory) | Lower Metal Enrichment of Virialized Gas in Minihalos | 22 pages, 7 figures, submitted to ApJ, comments welcome | null | 10.1086/524724 | null | astro-ph | null | We differentiate between the metal enrichment of the gas in virialized
minihalos and that of the intergalactic medium at high redshift, pertinent to
cosmological reionization, with the initial expectation that gas in the high
density regions within formed dark matter halos may be more robust thus
resistant to mixing with lower density intergalactic medium. Using detailed
hydrodynamic simulations of gas clouds in minihalos subject to destructive
processes associated with the encompassing intergalactic shocks carrying
metal-enriched gas, we find, as an example, that, for realistic shocks of
velocities of 10-100km/s, more than (90%,65%) of the high density gas with
rho>500 rhob inside a minihalo virialized at z=10 of mass (10^7,10^6)Msun
remains at a metallicity lower than 3% of that of the intergalactic medium by
redshift z=6. It may be expected that the high density gas in minihalos becomes
fuel for subsequent star formation, when they are incorporated into larger
halos where efficient atomic cooling can induce gas condensation hence star
formation. Since minihalos virialize at high redshift when the universe is not
expected to have been significantly reionized, the implication is that gas in
virialized minihalos may provide an abundant reservoir of primordial gas to
possibly allow for the formation of Population-III metal-free stars to extend
to much lower redshift than otherwise expected based on the enrichment of
intergalactic medium.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 13:50:07 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cen",
"Renyue",
"",
"Princeton University Observatory"
],
[
"Riquelme",
"Mario A.",
"",
"Princeton University Observatory"
]
] |
0704.3546 | Zakaria Moktadir Dr | Z. Moktadir, H. Wensink and M. Kraft | Scaling properties of pyrex and silicon surfaces blasted with sharp
particles | null | null | 10.1016/j.physa.2007.11.026 | null | cond-mat.stat-mech | null | The blasting of brittle materials with sharp particles is an important
fabrication technology in many industrial processes. In particular, for
micro-systems, it allows the production of devices with feature sizes down to
few tens of microns. An important parameter of this process is the surface
roughness of post-blasted surfaces. In this work the scaling properties of
Pyrex glass and silicon surfaces after bombardment with alumina particles is
investigated. The targets were bombarded at normal incidence using alumina
particles with two different average sizes, $29\mu m$ and $9\mu m$,
respectively. This investigation indicates that the resulting surfaces have
multifractal properties. Applying multifractal detrended fluctuation analysis
(MFDFA) allowed us to determine the singularity spectrum of the surfaces. This
spectrum did not depend on the target material or on the size of the particles.
Several parameters quantifying relevant quantities were determined. We argue
that for scales below $5 \mu m$, fracture processes are dominant while at large
scales long range correlations are responsible for the multifractal behaviour.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:05:16 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Moktadir",
"Z.",
""
],
[
"Wensink",
"H.",
""
],
[
"Kraft",
"M.",
""
]
] |
0704.3547 | Anton Ilderton | Thomas Heinzl and Anton Ilderton | Noncommutativity from spectral flow | 31 pages, one Postscript figure | J.Phys.A40:9097-9125,2007 | 10.1088/1751-8113/40/30/029 | null | hep-th | null | We investigate the transition from second to first order systems. This
transforms configuration space into phase space and hence introduces
noncommutativity in the former. Quantum mechanically, the transition may be
described in terms of spectral flow. Gaps in the energy or mass spectrum may
become large which effectively truncates the available state space. Using both
operator and path integral languages we explicitly discuss examples in quantum
mechanics, (light-front) quantum field theory and string theory.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:06:42 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Heinzl",
"Thomas",
""
],
[
"Ilderton",
"Anton",
""
]
] |
0704.3548 | Paolo G. Radaelli | E. Montanari, G. Calestani, L. Righi, E. Gilioli, F. Bolzoni, K.S.
Knight, P.G. Radaelli | Structural anomalies at the magnetic transition in centrosymmetric
BiMnO$_3$ | 4 pages, 4 figures | null | 10.1103/PhysRevB.75.220101 | null | cond-mat.str-el | null | The structural properties of BiMn$O_3$ were determined from neutron powder
diffraction data as a function of temperature and magnetic field. The structure
at all temperatures was found to be centrosymmetric with space group $C2/c$,
which is incompatible with ferroelectricity. At T$_C\simeq 100 K$, we observed
the onset of a large magnetoelastic strain, proportional to the square of the
magnetization. We interpret this structural rearrangement, together with the
previously observed magnetodielectric anomalies, as due to the need to optimize
the partially frustrated magnetic interactions.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:24:17 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Montanari",
"E.",
""
],
[
"Calestani",
"G.",
""
],
[
"Righi",
"L.",
""
],
[
"Gilioli",
"E.",
""
],
[
"Bolzoni",
"F.",
""
],
[
"Knight",
"K. S.",
""
],
[
"Radaelli",
"P. G.",
""
]
] |
0704.3549 | Celal Harabati | Celal Harabati, Kenneth G. Kay | Semiclassical initial value calculations of collinear helium atom | 24 pages, 3 figures. Submitted to J. Phys. B | The Journal of Chemical Physics, 127, 084104, (2007) | 10.1063/1.2771173 | null | quant-ph | null | Semiclassical calculations using the Herman-Kluk initial value treatment are
performed to determine energy eigenvalues of bound and resonance states of the
collinear helium atom. Both the $eZe$ configuration (where the classical motion
is fully chaotic) and the $Zee$ configuration (where the classical dynamics is
nearly integrable) are treated. The classical motion is regularized to remove
singularities that occur when the electrons collide with the nucleus. Very good
agreement is obtained with quantum energies for bound and resonance states
calculated by the complex rotation method.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:17:11 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Harabati",
"Celal",
""
],
[
"Kay",
"Kenneth G.",
""
]
] |
0704.3550 | Alessandro Nagar | Thibault Damour, Alessandro Nagar | Final spin of a coalescing black-hole binary: an Effective-One-Body
approach | 8 pages, two figures. To appear in Phys. Rev. D | Phys.Rev.D76:044003,2007 | 10.1103/PhysRevD.76.044003 | null | gr-qc | null | We update the analytical estimate of the final spin of a coalescing
black-hole binary derived within the Effective-One-Body (EOB) approach. We
consider unequal-mass non-spinning black-hole binaries. It is found that a more
complete account of relevant physical effects (higher post-Newtonian accuracy,
ringdown losses) allows the {\it analytical} EOB estimate to `converge towards'
the recently obtained {\it numerical} results within 2%. This agreement
illustrates the ability of the EOB approach to capture the essential physics of
coalescing black-hole binaries. Our analytical approach allows one to estimate
the final spin of the black hole formed by coalescing binaries in a mass range
($\nu=m_1m_2/(m_1+m_2)^2 < 0.16 $) which is not presently covered by numerical
simulations.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:22:01 GMT"
},
{
"version": "v2",
"created": "Thu, 26 Jul 2007 15:30:22 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Damour",
"Thibault",
""
],
[
"Nagar",
"Alessandro",
""
]
] |
0704.3551 | J\"org Langowski | Annika Wedemeier, Holger Merlitz, Chen-Xu Wu, and J\"org Langowski | Modelling diffusional transport in the interphase cell nucleus | 9 pages, 8 figures | null | 10.1063/1.2753158 | null | physics.bio-ph physics.comp-ph | null | In this paper a lattice model for diffusional transport of particles in the
interphase cell nucleus is proposed. Dense networks of chromatin fibers are
created by three different methods: randomly distributed, non-interconnected
obstacles, a random walk chain model, and a self avoiding random walk chain
model with persistence length. By comparing a discrete and a continuous version
of the random walk chain model, we demonstrate that lattice discretization does
not alter particle diffusion. The influence of the 3D geometry of the fiber
network on the particle diffusion is investigated in detail, while varying
occupation volume, chain length, persistence length and walker size. It is
shown that adjacency of the monomers, the excluded volume effect incorporated
in the self avoiding random walk model, and, to a lesser extent, the
persistence length, affect particle diffusion. It is demonstrated how the
introduction of the effective chain occupancy, which is a convolution of the
geometric chain volume with the walker size, eliminates the conformational
effects of the network on the diffusion, i.e., when plotting the diffusion
coefficient as a function of the effective chain volume, the data fall onto a
master curve.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:25:09 GMT"
},
{
"version": "v2",
"created": "Fri, 8 Jun 2007 11:53:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wedemeier",
"Annika",
""
],
[
"Merlitz",
"Holger",
""
],
[
"Wu",
"Chen-Xu",
""
],
[
"Langowski",
"Jörg",
""
]
] |
0704.3552 | Fausto Vagnetti | D. Trevese, F. Vagnetti, S. Puccetti, F. Fiore, M. Tomei, M. A.
Bershady | An X-ray Survey in SA 57 with XMM-Newton | 13 pages, 6 figures, 4 tables, A&A in press | null | 10.1051/0004-6361:20077359 | null | astro-ph | null | The maximum number density of Active Galactic Nuclei (AGNs), as deduced from
X-ray studies, occurs at z<~1, with lower luminosity objects peaking at smaller
redshifts. Optical studies lead to a different evolutionary behaviour, with a
number density peaking at z~2 independently of the intrinsic luminosity, but
this result is limited to active nuclei brighter than the host galaxy. A
selection based on optical variability can detect low luminosity AGNs (LLAGNs),
where the host galaxy light prevents the identification by non-stellar colours.
We want to collect X-ray data in a field where it exists an optically-selected
sample of "variable galaxies'', i.e. variable objects with diffuse appearance,
to investigate the X-ray and optical properties of the population of AGNs,
particularly of low luminosity ones, where the host galaxy is visible. We
observed a field of 0.2 deg^2 in the Selected Area 57, for 67ks with
XMM-Newton. We detected X-ray sources, and we correlated the list with a
photographic survey of SA 57, complete to B_J~23 and with available
spectroscopic data. We obtained a catalogue of 140 X-ray sources to limiting
fluxes 5x10^-16, 2x10^-15 erg/cm^2/s in the 0.5-2 keV and 2-10 keV
respectively, 98 of which are identified in the optical bands. The X-ray
detection of part of the variability-selected candidates confirms their AGN
nature. Diffuse variable objects populate the low luminosity side of the
sample. Only 25/44 optically-selected QSOs are detected in X-rays. 15% of all
QSOs in the field have X/O<0.1.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:26:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Trevese",
"D.",
""
],
[
"Vagnetti",
"F.",
""
],
[
"Puccetti",
"S.",
""
],
[
"Fiore",
"F.",
""
],
[
"Tomei",
"M.",
""
],
[
"Bershady",
"M. A.",
""
]
] |
0704.3553 | Jean-Yves Ollitrault | Hans-Joachim Drescher, Adrian Dumitru, Clement Gombeaud and Jean-Yves
Ollitrault | The centrality dependence of elliptic flow, the hydrodynamic limit, and
the viscosity of hot QCD | 5 pages, 2 figures. Extended discussion of the results, in particular
of lower viscosity and sound velocity required by CGC initial conditions | Phys.Rev.C76:024905,2007 | 10.1103/PhysRevC.76.024905 | SPhT-T07/049 | nucl-th | null | We show that the centrality and system-size dependence of elliptic flow
measured at RHIC are fully described by a simple model based on eccentricity
scaling and incomplete thermalization. We argue that the elliptic flow is at
least 25% below the (ideal) ``hydrodynamic limit'', even for the most central
Au-Au collisions. This lack of perfect equilibration allows for estimates of
the effective parton cross section in the Quark-Gluon Plasma and of its
viscosity to entropy density ratio. We also show how the initial conditions
affect the transport coefficients and thermodynamic quantities extracted from
the data, in particular the viscosity and the speed of sound.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 18:20:59 GMT"
},
{
"version": "v2",
"created": "Thu, 28 Jun 2007 12:17:46 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Drescher",
"Hans-Joachim",
""
],
[
"Dumitru",
"Adrian",
""
],
[
"Gombeaud",
"Clement",
""
],
[
"Ollitrault",
"Jean-Yves",
""
]
] |
0704.3554 | Rohta Takahashi | Rohta Takahashi | Advection-dominated accretion flows with causal viscosity | Takahashi R., 2007, A&A, 461, 393 | Astron.Astrophys.461:393,2007 | 10.1051/0004-6361:20066197 | null | astro-ph | null | We present the basic equations and sample solutions for the steady-state
global transonic solutions of the advection-dominated accretion flows (ADAFs)
with a causal viscosity prescription. The procedures for the stable numerical
calculations and all explicit formula for obtaining the solutions of ADAFs are
also presented. We solve the transonic solutions of ADAFs by using the explicit
numerical integrations, as in the Runge-Kutta method. In this calculation
method, we first solve the physical values at the sonic radius where
L'Hopital's rule is used. Then, we numerically solve the coupled differential
equations of the radial velocity, the angular momentum, and the sound speed
from the sonic radius in the inward and outward directions. By the calculation
procedures presented in this paper, we can cover all parameter spaces of the
transonic solutions of ADAFs. Sample transonic solutions for ADAF-thick disk
and ADAF-thin disk are presented. The explicit formula for the analytical
expansion around the singular points, the sonic and the viscous points, are
presented. If we set the diffusion timescale to null, the formalism in this
study becomes the formalism of the acausal viscosity that is usually used in
past studies for calculating of the ADAF structure.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:32:47 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Takahashi",
"Rohta",
""
]
] |
0704.3555 | Danyal Winters | H.-J. Kluge, W. Quint and D.F.A. Winters | Atomic physics experiments with trapped and cooled highly charged ions | 8 pages, 5 figures, 1 table. accepted for Journal of Physics
Conference Series (2006) | null | 10.1088/1742-6596/58/1/002 | null | physics.atom-ph physics.gen-ph | null | Trapping and cooling techniques have become very important for many
fundamental experiments in atomic physics. When applied to highly charged ions
confined in Penning traps, these procedures are very effective for testing
quantum electrodynamics in extreme electromagnetic fields produced by heavy
highly charged ions such as uranium U$^{91+}$. In addition, fundamental
constants or nuclear ground state properties can be determined with high
accuracy in these simple systems. Finally, by studying a single trapped
radioactive ion, its nuclear decay can be studied in detail by observing the
disappearance of the signal of the mother and the appearance of that of the
daughter isotope. Such experiments on highly charged ions at extremely low
energy will become possible by the HITRAP facility which is currently being
built up at GSI. Also the future Facility for Antiproton and Ion Research
(FAIR) will be briefly described which is expected to be operational by 2014.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:37:41 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Kluge",
"H. -J.",
""
],
[
"Quint",
"W.",
""
],
[
"Winters",
"D. F. A.",
""
]
] |
0704.3556 | Simon Moulin | Simon Moulin (LMJL) | Low frequency dispersive estimates for the wave equation in higher
dimensions | 10 pages | Asymptotic Analysis 60, 1-2 (2008) 15-27 | null | null | math.AP | null | We prove dispersive estimates at low frequency in dimensions n greater or
equal to 4 for the wave equation for a very large class of real-valued
potentials, provided the zero is neither an eigenvalue nor a resonance.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:37:50 GMT"
},
{
"version": "v2",
"created": "Fri, 6 Jul 2007 15:21:36 GMT"
},
{
"version": "v3",
"created": "Mon, 16 Jul 2007 18:58:46 GMT"
},
{
"version": "v4",
"created": "Mon, 17 Sep 2007 12:19:23 GMT"
}
] | 2009-02-11T00:00:00 | [
[
"Moulin",
"Simon",
"",
"LMJL"
]
] |
0704.3557 | Jan Forbrich | Jan Forbrich, Maria Massi, Eduardo Ros, Andreas Brunthaler, Karl
Menten (Max-Planck-Institut f\"ur Radioastronomie, Bonn) | Searching for coronal radio emission from protostars using
Very-Long-Baseline Interferometry | 8 pages, 4 figures, accepted for publication in A&A | null | 10.1051/0004-6361:20077113 | null | astro-ph | null | In order to directly study the role of magnetic fields in the immediate
vicinity of protostars, we use Very-Long-Baseline Interferometry (VLBI), aiming
at the detection of non-thermal centimetric radio emission. This is technically
the only possibility to study coronal emission at sub-AU resolution. We
performed VLBI observations of the four nearby protostars HL Tau, LDN 1551
IRS5, EC 95, and YLW 15 in order to look for compact non-thermal centimetric
radio emission. For maximum sensitivity, we used the High Sensitivity Array
(HSA) where possible, involving the Very Long Baseline Array (VLBA), the phased
Very Large Array (VLA), as well as the Arecibo, Green Bank, and Effelsberg
radio telescopes. While all four protostars were detected in VLA-only data,
only one source (YLW 15 VLA 2) was detected in the VLBI data. The possibility
of non-detections due to free-free absorption, possibly depending on source
geometry, is considered. For YLW 15 VLA 2, the prospects for an accurate orbit
determination appear to be good.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:54:22 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Forbrich",
"Jan",
"",
"Max-Planck-Institut für Radioastronomie, Bonn"
],
[
"Massi",
"Maria",
"",
"Max-Planck-Institut für Radioastronomie, Bonn"
],
[
"Ros",
"Eduardo",
"",
"Max-Planck-Institut für Radioastronomie, Bonn"
],
[
"Brunthaler",
"Andreas",
"",
"Max-Planck-Institut für Radioastronomie, Bonn"
],
[
"Menten",
"Karl",
"",
"Max-Planck-Institut für Radioastronomie, Bonn"
]
] |
0704.3558 | Eliahu Levy | Eliahu Levy | Weakly Compact "Matrices", Fubini-Like Property and Extension of Densely
Defined Semigroups of Operators | 8 pages. v2: the exposition has been somewhat improved and
unnecessary restrictions removed. v3: added references and acknowledgment | null | null | null | math.FA math.OA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Taking matrix as a synonym for a numerical function on the Cartesian product
of two (in general, infinite) sets, a simple purely algebraic "reciprocity
property" says that the set of rows spans a finite-dim space iff the set of
columns does so. Similar topological reciprocity properties serve to define
strongly compact and weakly compact matrices, featured in the well-known basic
facts about almost periodic functions and about compact operators. Some
properties, especially for the weak compact case, are investigated, such as the
connection with the matrix having a Fubini-like property for general means.
These are applied to prove possibility of extension to the entire semigroup of
bounded densely defined semigroups of operators in a Banach space with weak
continuity properties.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:45:46 GMT"
},
{
"version": "v2",
"created": "Sun, 17 Feb 2008 18:41:10 GMT"
},
{
"version": "v3",
"created": "Thu, 28 Aug 2008 21:32:14 GMT"
}
] | 2008-08-29T00:00:00 | [
[
"Levy",
"Eliahu",
""
]
] |
0704.3559 | Andr\'e Ploegh | E.A. Bergshoeff, J. Hartong, A. Ploegh, J. Rosseel and D. Van den
Bleeken | Pseudo-supersymmetry and a Tale of Alternate Realities | 32 pages | JHEP0707:067,2007 | 10.1088/1126-6708/2007/07/067 | UG-07-02, KUL-TF-07/08 | hep-th | null | We discuss how all variant 10d and 11d maximal supergravities, including star
supergravities and supergravities in different signatures, can be obtained as
different real slices of three complex actions. As an application we study the
recently introduced domain-wall/cosmology correspondence in this approach. We
give an example in 9d and 10d where the domain-wall and corresponding cosmology
can be viewed as different real slices of the same complex solution. We argue
how in this case the pseudo-supersymmetry of the cosmological solutions can be
understood as the invariance under supersymmetry of a variant supergravity.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:47:46 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bergshoeff",
"E. A.",
""
],
[
"Hartong",
"J.",
""
],
[
"Ploegh",
"A.",
""
],
[
"Rosseel",
"J.",
""
],
[
"Bleeken",
"D. Van den",
""
]
] |
0704.3560 | Christian Blum | Christian Blum, Willem L. Vos, and Vinod Subramaniam | Tuning Spontaneous Emission versus Forster Energy Transfer in Biological
Systems by Manipulating the Density of Photonic States | 12 pages, 3 figures, pdf | null | null | null | physics.chem-ph physics.bio-ph | null | We theoretically discuss how to tune the competition between Forster transfer
and spontaneous emission in a continuous and nondestructive fashion. The
proposed approach is especially suitable for delicate biological systems like
light harvesting complexes and fluorescent protein oligomers. We demonstrate
that the manipulation of the density of photonic states at the emission
frequency of the energy donor results in a change of the quantum efficiencies
of the competing energy transfer and spontaneous emission processes. This
change will be manifested in a modification of the donor and acceptor emission
intensities. Thus, by controlling the local density of photonic states Forster
coupled systems can be manipulated and analyzed without the need to physically
separate donor and acceptor chromophores for individual analysis, which is of
interest, for example, for oligomeric reef coral fluorescent proteins.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:49:20 GMT"
},
{
"version": "v2",
"created": "Tue, 19 Jun 2007 12:41:39 GMT"
}
] | 2007-06-19T00:00:00 | [
[
"Blum",
"Christian",
""
],
[
"Vos",
"Willem L.",
""
],
[
"Subramaniam",
"Vinod",
""
]
] |
0704.3561 | Martin Bays | Martin Bays and Boris Zilber | Covers of Multiplicative Groups of Algebraically Closed Fields of
Arbitrary Characteristic | Version accepted by the Bull. London Math. Soc | Bull. Lond. Math. Soc. 43 (2011), no. 4, 689-702 | 10.1112/blms/bdq131 | null | math.LO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that algebraic analogues of universal group covers, surjective group
homomorphisms from a $\mathbb{Q}$-vector space to $F^{\times}$ with "standard
kernel", are determined up to isomorphism of the algebraic structure by the
characteristic and transcendence degree of $F$ and, in positive characteristic,
the restriction of the cover to finite fields. This extends the main result of
"Covers of the Multiplicative Group of an Algebraically Closed Field of
Characteristic Zero" (B. Zilber, JLMS 2007), and our proof fills a hole in the
proof given there.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:53:18 GMT"
},
{
"version": "v2",
"created": "Tue, 1 Jul 2008 10:55:34 GMT"
},
{
"version": "v3",
"created": "Fri, 30 Jan 2009 20:19:51 GMT"
},
{
"version": "v4",
"created": "Tue, 4 Jan 2011 17:53:13 GMT"
}
] | 2021-07-14T00:00:00 | [
[
"Bays",
"Martin",
""
],
[
"Zilber",
"Boris",
""
]
] |
0704.3562 | Luis Labarga | ZEUS Collaboration: S. Chekanov, et al | Measurement of D mesons Production in Deep Inelastic Scattering at HERA | 46 pages, 9 figures, 10 tables, accepted for publication in JHEP | JHEP 0707:074,2007 | 10.1088/1126-6708/2007/07/074 | DESY-07-052 | hep-ex | null | Charm production in deep inelastic scattering has been measured with the ZEUS
detector at HERA using an integrated luminosity of 82 pb^{-1}. Charm has been
tagged by reconstructing D^{*+}, D^0, D^{+} and D_s^+ (+ c.c.) charm mesons.
The charm hadrons were measured in the kinematic range p_T(D^{*+},D^0,D^{+}) >
3 GeV, p_T(D_s^+)>2 GeV and |\eta(D)| < 1.6 for 1.5 < Q^2 < 1000 GeV^2 and 0.02
< y < 0.7. The production cross sections were used to extract charm
fragmentation ratios and the fraction of c quarks hadronising into a particular
charm meson in the kinematic range considered. The cross sections were compared
to the predictions of next-to-leading-order QCD, and extrapolated to the full
kinematic region in p_T(D) and \eta(D) in order to determine the open-charm
contribution, F_2^{c\bar{c}}(x,Q^2), to the proton structure function F_2.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:56:27 GMT"
},
{
"version": "v2",
"created": "Wed, 18 Jul 2007 15:34:42 GMT"
}
] | 2012-08-03T00:00:00 | [
[
"ZEUS Collaboration",
"",
""
],
[
"Chekanov",
"S.",
""
]
] |
0704.3563 | Jean Alexandre | Jean Alexandre and Konstantinos Farakos | Path integral quantization of scalar fluctuations above a kink | Comments added | J.Phys.A41:015401,2008 | 10.1088/1751-8113/41/1/015401 | null | hep-th hep-ph | null | We quantize scalar fluctuations in 1+1 dimensions above a classical
background kink. The properties of the effective action for the corresponding
classical field are studied with an exact functional method, alternative to
exact Wilsonian renormalization, where the running parameter is a bare mass,
and the regulator of the quantum theory is fixed. We extend this approach, in
an appendix, to a Yukawa interaction in higher dimension.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:56:30 GMT"
},
{
"version": "v2",
"created": "Mon, 12 Nov 2007 17:16:51 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Alexandre",
"Jean",
""
],
[
"Farakos",
"Konstantinos",
""
]
] |
0704.3564 | Robert Seiringer | Rupert L. Frank, Christian Hainzl, Serguei Naboko, Robert Seiringer | The critical temperature for the BCS equation at weak coupling | Revised Version. To appear in J. Geom. Anal | J. Geom. Anal. 17, 559-568 (2007) | null | null | cond-mat.supr-con cond-mat.other math-ph math.MP | null | For the BCS equation with local two-body interaction $\lambda V(x)$, we give
a rigorous analysis of the asymptotic behavior of the critical temperature as
$\lambda \to 0$. We derive necessary and sufficient conditions on $V(x)$ for
the existence of a non-trivial solution for all values of $\lambda>0$.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 14:59:09 GMT"
},
{
"version": "v2",
"created": "Wed, 24 Oct 2007 20:13:38 GMT"
}
] | 2008-02-06T00:00:00 | [
[
"Frank",
"Rupert L.",
""
],
[
"Hainzl",
"Christian",
""
],
[
"Naboko",
"Serguei",
""
],
[
"Seiringer",
"Robert",
""
]
] |
0704.3565 | Antonio Bernini | Antonio Bernini, Elisa Pergola | Enumerating permutations avoiding more than three Babson - Steingr\'\i
msson patterns | null | null | null | null | math.CO | null | Not long ago, Claesson and Mansour proposed some conjectures about the
enumeration of the permutations avoiding more than three Babson - Steingr\'\i
msson patterns (generalized patterns of type $(1,2)$ or $(2,1)$). The avoidance
of one, two or three patterns has already been considered. Here, the cases of
four and five forbidden patterns are solved and the exact enumeration of the
permutations avoiding them is given, confirming the conjectures of Claesson and
Mansour. The approach we use can be easily extended to the cases of more than
five forbidden patterns.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:03:48 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bernini",
"Antonio",
""
],
[
"Pergola",
"Elisa",
""
]
] |
0704.3566 | Martin Plumer | M.L. Plumer | Biquadratic antisymmetric exchange and the magnetic phase diagram of
magnetoelectric CuFeO$_2$ | 7 pages, 9 figures | null | 10.1103/PhysRevB.76.144411 | null | cond-mat.str-el | null | Biquadratic {\it antisymmetric} exchange terms of the form $ - [C_{ij}
e^{\alpha}_{ij}({\bf s}_i\times{\bf s}_j)_z]^2$, where ${\bf e}_{ij}$ is the
unit vector connecting sites $i$ and $j$ and $\alpha = x,y$, due partially to
magnetoelectric coupling effects, are shown to be responsible for the spin-flop
helical phase in CuFeO$_2$ at low magnetic field and temperature. Usual
biquadratic {\it symmetric} exchange, likely due to magnetoelastic coupling, is
found to support the stability of axial magnetic states at higher fields in
this nearly-Heisenberg like stacked triangular antiferromagnet. A model
Hamiltonian which also includes substantial interplane and higher-neighbor
intraplane exchange interactions, reproduces the unique series of observed
commensurate and incommensurate periodicity phases with increasing applied
magnetic field in this highly frustrated system. The magnetic field-temperature
phase diagram is discussed in terms of a Landau-type free energy.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:04:57 GMT"
},
{
"version": "v2",
"created": "Wed, 4 Jul 2007 13:21:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Plumer",
"M. L.",
""
]
] |
0704.3567 | Gernot Maier | Gernot Maier, Johannes Knapp | Cosmic-Ray Events as Background in Imaging Atmospheric Cherenkov
Telescopes | Accepted by Journal of Astroparticle Physics | Astropart.Phys.28:72-81,2007 | 10.1016/j.astropartphys.2007.04.009 | null | astro-ph | null | The dominant background for observations of gamma-rays in the energy region
above 50 GeV with Imaging Atmospheric Cherenkov telescopes are cosmic-ray
events. The images of most of the cosmic ray showers look significantly
different from those of gamma-rays and are therefore easily discriminated.
However, a small fraction of events seems to be indistinguishable from
gamma-rays. This constitutes an irreducible background to the observation of
high-energy gamma-ray sources, and limits the sensitivity achievable with a
given instrument. Here, a Monte Carlo study of gamma-like cosmic-ray events is
presented. The nature of gamma-like cosmic-ray events, the shower particles
that are responsible for the gamma-like appearance, and the dependence of these
results on the choice of the hadronic interaction model are investigated. Most
of the gamma-like cosmic ray events are characterised by the production of
high-energy pi0's early in the shower development which dump most of the shower
energy into electromagnetic sub-showers. Also Cherenkov light from single muons
can mimic gamma-rays in close-by pairs of telescopes. Differences of up to 25%
in the collection area for gamma-like proton showers between QGSJet/FLUKA and
Sibyll/FLUKA simulations have been found.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:10:46 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Maier",
"Gernot",
""
],
[
"Knapp",
"Johannes",
""
]
] |
0704.3568 | Ilia Gogoladze | Ilia Gogoladze, Chin-Aik Lee, Tianjun Li, Qaisar Shafi | Fermion Masses and Mixings in GUTs with Non-Canonical U(1)_Y | 18 pages | Phys.Rev.D78:015024,2008 | 10.1103/PhysRevD.78.015024 | BA - 07 - 20, MAFP - 07 - 12 | hep-ph | null | We discuss fermion masses and mixings in models derived from orbifold GUTs
such that gauge coupling unification is achieved without low energy
supersymmetry by utilizing a non-canonical U(1)_Y. A gauged U(1)_X flavor
symmetry plays an essential role, and the Green-Schwarz mechanism is invoked in
anomaly cancellations. Models containing vector-like particles with masses
close to M_{GUT} are also discussed.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:11:33 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gogoladze",
"Ilia",
""
],
[
"Lee",
"Chin-Aik",
""
],
[
"Li",
"Tianjun",
""
],
[
"Shafi",
"Qaisar",
""
]
] |
0704.3569 | Osvaldo Civitarese | A. Ballesteros, O. Civitarese, F. J. Herranz, M. Reboiro | Generalized rotational hamiltonians from nonlinear angular momentum
algebras | 3 figures, 6 pages, 15 references. Phys. Rev. C (in press, ms
CZ10038) | Phys.Rev.C75:044316,2007 | 10.1103/PhysRevC.75.044316 | null | nucl-th | null | Higgs algebras are used to construct rotational Hamiltonians. The
correspondence between the spectrum of a triaxial rotor and the spectrum of a
cubic Higgs algebra is demonstrated. It is shown that a suitable choice of the
parameters of the polynomial algebra allows for a precise identification of
rotational properties. The harmonic limit is obtained by a contraction of the
algebra, leading to a linear symmetry.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:12:59 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Ballesteros",
"A.",
""
],
[
"Civitarese",
"O.",
""
],
[
"Herranz",
"F. J.",
""
],
[
"Reboiro",
"M.",
""
]
] |
0704.3570 | Matteo Beccaria | Matteo Beccaria | Anomalous dimensions at twist-3 in the sl(2) sector of N=4 SYM | 26 pages, JHEP style | JHEP 0706:044,2007 | 10.1088/1126-6708/2007/06/044 | null | hep-th | null | We consider twist-3 operators in the sl(2) sector of N=4 SYM built out of
three scalar fields with derivatives. We extract from the Bethe Ansatz
equations of this sector the exact lowest anomalous dimension gamma(s) of
scaling fields for several values of the operator spin s. We propose compact
closed expressions for the spin dependence of gamma(s) up to the four loop
level and show that they obey a simple new twist-3 transcendentality principle.
As a check, we reproduce the four loop universal cusp anomalous dimension
governing the logarithmic large spin limit of gamma(s).
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:46:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Beccaria",
"Matteo",
""
]
] |
0704.3571 | Joel Giedt | Maxime Gabella, Tony Gherghetta, Joel Giedt | A Gravity Dual and LHC Study of Single-Sector Supersymmetry Breaking | 35 pages, 6 figures, LaTeX | Phys.Rev.D76:055001,2007 | 10.1103/PhysRevD.76.055001 | UMN-TH-2542/07, FTPI-MINN-07/09 | hep-ph hep-th | null | We propose a gravitational dual of ``single-sector'' models of supersymmetry
breaking which contain no messenger sector and naturally explain the scale of
supersymmetry breaking and the fermion mass hierarchy. In five dimensions these
models can be given a simple interpretation. Inspired by flux-background
solutions of type IIB supergravity, a metric background that deviates from
AdS_5 in the IR breaks supersymmetry, while the fermion mass hierarchy results
from the wavefunction overlap of bulk fermions with a UV-confined Higgs field.
The first and second generation squarks and sleptons, which are localized near
the IR brane, directly feel the supersymmetry breaking and obtain masses of
order 10 TeV. These are interpreted as composite states of the dual 4D theory.
The gauginos and third generation squarks and sleptons are elementary states
that obtain soft masses of order 1 TeV at the loop level via direct gauge
mediation. This particle spectrum leads to distinctive signatures at the LHC,
similar to the usual gauge mediation with a neutralino NLSP that decays
promptly to a gravitino LSP, but with lower event rates. Nevertheless we show
that with 1-10 fb^{-1} of LHC data "single-sector" models can easily be
detected above background and distinguished from conventional gravity and gauge
mediation.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:41:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gabella",
"Maxime",
""
],
[
"Gherghetta",
"Tony",
""
],
[
"Giedt",
"Joel",
""
]
] |
0704.3572 | Patrick Weltevrede | P. Weltevrede, B.W. Stappers, R.T. Edwards | The subpulse modulation properties of pulsars at 92 cm and the frequency
dependence of subpulse modulation | 30 pages, 10 figures, accepted for publication in A&A, astro-ph
version is missing 191 figures due to file size restrictions. Please download
the appendix from
http://www.astron.nl/~stappers/wiki/doku.php?id=resources:publications | null | 10.1051/0004-6361:20066855 | null | astro-ph | null | A large sample of pulsars has been observed to study their subpulse
modulation at an observing wavelength (when achievable) of both 21 and 92 cm
using the Westerbork Synthesis Radio Telescope. In this paper we present the
92-cm data and a comparison is made with the already published 21-cm results.
We analysed 191 pulsars at 92 cm using fluctuation spectra. The sample of
pulsars is as unbiased as possible towards any particular pulsar
characteristics. For 15 pulsars drifting subpulses are discovered for the first
time and 26 of the new drifters found in the 21-cm data are confirmed. We
discovered nulling for 8 sources and 8 pulsars are found to intermittently emit
single pulses that have pulse energies similar to giant pulses. It is estimated
that at least half of the total population of pulsars have drifting subpulses
when observations with a high enough signal-to-noise ratio would be available.
It could well be that the drifting subpulse mechanism is an intrinsic property
of the emission mechanism itself, although for some pulsars it is difficult or
impossible to detect. Drifting subpulses are in general found at both
frequencies, although the chance of detecting drifting subpulses is possibly
slightly higher at 92 cm. It appears that the youngest pulsars have the most
disordered subpulses and the subpulses become more and more organized into
drifting subpulses as the pulsar ages. The correlations with the modulation
indices are argued to be consistent with the picture in which the radio
emission can be divided in a drifting subpulse signal plus a quasi-steady
signal which becomes, on average, stronger at high observing frequencies. The
measured values of P3 at the two frequencies are highly correlated, but there
is no evidence for a correlation with other pulsar parameters.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:45:22 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Weltevrede",
"P.",
""
],
[
"Stappers",
"B. W.",
""
],
[
"Edwards",
"R. T.",
""
]
] |
0704.3573 | Andrea Maiorano | F. Belletti, M. Cotallo, A. Cruz, L. A. Fern\'andez, A. Gordillo, A.
Maiorano, F. Mantovani, E. Marinari, V. Mart\'in-Mayor, A. Mu\~noz-Sudupe, D.
Navarro, S. P\'erez-Gaviro, J. J. Ruiz-Lorenzo, S. F. Schifano, D. Sciretti,
A. Taranc\'on, R. Tripiccione, J. L. Velasco | Simulating spin systems on IANUS, an FPGA-based computer | 19 pages, 8 figures; submitted to Computer Physics Communications | Computer Physics Communications, 178 (3), p.208-216, (2008) | 10.1016/j.cpc.2007.09.006 | null | cond-mat.dis-nn cs.AR | null | We describe the hardwired implementation of algorithms for Monte Carlo
simulations of a large class of spin models. We have implemented these
algorithms as VHDL codes and we have mapped them onto a dedicated processor
based on a large FPGA device. The measured performance on one such processor is
comparable to O(100) carefully programmed high-end PCs: it turns out to be even
better for some selected spin models. We describe here codes that we are
currently executing on the IANUS massively parallel FPGA-based system.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:49:47 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Belletti",
"F.",
""
],
[
"Cotallo",
"M.",
""
],
[
"Cruz",
"A.",
""
],
[
"Fernández",
"L. A.",
""
],
[
"Gordillo",
"A.",
""
],
[
"Maiorano",
"A.",
""
],
[
"Mantovani",
"F.",
""
],
[
"Marinari",
"E.",
""
],
[
"Martín-Mayor",
"V.",
""
],
[
"Muñoz-Sudupe",
"A.",
""
],
[
"Navarro",
"D.",
""
],
[
"Pérez-Gaviro",
"S.",
""
],
[
"Ruiz-Lorenzo",
"J. J.",
""
],
[
"Schifano",
"S. F.",
""
],
[
"Sciretti",
"D.",
""
],
[
"Tarancón",
"A.",
""
],
[
"Tripiccione",
"R.",
""
],
[
"Velasco",
"J. L.",
""
]
] |
0704.3574 | Paul Benioff | Paul Benioff | Space of Quantum Theory Representations of Natural Numbers, Integers,
and Rational Numbers | 32 pages, 2 figures | null | null | null | quant-ph hep-th math-ph math.MP | null | This paper extends earlier work on quantum theory representations of natural
numbers N, integers I, and rational numbers Ra to describe a space of these
representations and transformations on the space. The space is parameterized by
4-tuple points in a parameter set. Each point, (k,m,h,g), labels a specific
representation of X = N, I, Ra as a Fock space F^{X}_{k,m,h} of states of
finite length strings of qukits q and a string state basis B^{X}_{k,m,h,g}. The
pair (m,h) locates the q string in a square integer lattice I \times I, k is
the q base, and the function g fixes the gauge or basis states for each q. Maps
on the parameter set induce transformations on on the representation space.
There are two shifts, a base change operator W_{k',k}, and a basis or gauge
transformation function U_{k}. The invariance of the axioms and theorems for N,
I, and Ra under any transformation is discussed along with the dependence of
the properties of W_{k',k} on the prime factors of k' and k. This suggests that
one consider prime number q's, q_{2}, q_{3}, q_{5}, etc. as elementary and the
base k q's as composites of the prime number q's.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:52:35 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Benioff",
"Paul",
""
]
] |
0704.3575 | Soeren Prell | Heavy Flavor Averaging Group (HFAG) (E. Barberio et al.) | Averages of b-hadron properties at the end of 2006 | null | null | null | null | hep-ex hep-ph | null | This article reports the world averages for measurements on b-hadron
properties obtained by the Heavy Flavor Averaging Group (HFAG) using the
available results at the end of 2006. In the averaging, the input parameters
used in the various analyses are adjusted (rescaled) to common values, and all
known correlations are taken into account. The averages include lifetimes,
neutral meson mixing parameters, parameters of semileptonic decays, branching
fractions of B decays to final states with open charm, charmonium and no charm,
and measurements related to CP asymmetries.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:18:25 GMT"
}
] | 2012-08-27T00:00:00 | [
[
"Heavy Flavor Averaging Group",
"",
""
]
] |
0704.3576 | Allal Ghanmi | Allal Ghanmi | A class of generalized complex Hermite polynomials | 13 pages. Minor corrections | J. Math. Anal. Appl., 340, no 2, (2008) 1395-1406 | 10.1016/j.jmaa.2007.10.001 | null | math.CA math-ph math.MP math.SP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A class of generalized complex polynomials of Hermite type, suggested by a
special magnetic Schrodinger operator, is introduced and some related basic
properties are discussed.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 18:48:54 GMT"
},
{
"version": "v2",
"created": "Mon, 20 Aug 2007 16:40:39 GMT"
},
{
"version": "v3",
"created": "Thu, 7 Aug 2008 11:27:24 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Ghanmi",
"Allal",
""
]
] |
0704.3577 | Odesskii Alexander | Alexander Odesskii | A family of (2+1)-dimensional hydrodynamic type systems possessing
pseudopotential | 16 pages, latex | null | null | null | math.AP hep-th math-ph math.MP nlin.SI | null | We construct a family of integrable hydrodynamic type systems with three
independent and n>1 dependent variables in terms of solutions of linear system
of PDEs with rational coefficients. We choose the existence of a
pseudopotential as a criterion of integrability. In the case n=2 this family is
a general solution of the classification problem for such systems. We give also
an elliptic analog of this family in the case n>2.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 15:57:31 GMT"
},
{
"version": "v2",
"created": "Sat, 12 May 2007 15:21:28 GMT"
},
{
"version": "v3",
"created": "Fri, 1 Jun 2007 13:02:36 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Odesskii",
"Alexander",
""
]
] |
0704.3578 | Ivan Sergienko | Silvia Picozzi, Kunihiko Yamauchi, Biplab Sanyal, Ivan A. Sergienko,
Elbio Dagotto | Dual nature of improper ferroelectricity in a magnetoelectric
multiferroic | 6 pages, 4 figures. Submitted for publication | null | 10.1103/PhysRevLett.99.227201 | null | cond-mat.mtrl-sci cond-mat.str-el | null | Using first principles calculations, we study the microscopic origin of
ferroelectricity (FE) induced by magnetic order in the orthorhombic HoMnO3. We
obtain the largest ferroelectric polarization observed in the whole class of
improper magnetic ferroelectrics to date. We find that the two proposed
mechanisms for FE in multiferroics, lattice- and electronic-based, are
simultaneously active in this compound: a large portion of the ferroelectric
polarization arises due to quantum-mechanical effects of electron orbital
polarization, in addition to the conventional polar atomic displacements. An
interesting mechanism for switching the magnetoelectric domains by an electric
field via a 180-degree coherent rotation of Mn spins is also proposed.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:20:42 GMT"
},
{
"version": "v2",
"created": "Tue, 8 May 2007 14:38:29 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Picozzi",
"Silvia",
""
],
[
"Yamauchi",
"Kunihiko",
""
],
[
"Sanyal",
"Biplab",
""
],
[
"Sergienko",
"Ivan A.",
""
],
[
"Dagotto",
"Elbio",
""
]
] |
0704.3579 | Jean-Pierre Luminet | Jean-Pierre Luminet | The Rise of Big Bang Models, from Myth to Theory and Observations | 15 pages, pdf only. Invited talk at conference "Antropogenesi :
Dall'energia al fenomeno umano", 19-21 october, Portogruaro (Italy). To
appear in Proceedings, eds. A. Pavan, E. Magno | null | null | null | astro-ph | null | We provide an epistemological analysis of the developments of relativistic
cosmology from 1917 to 2006, based on the seminal articles by Einstein, de
Sitter, Friedmann, Lemaitre, Hubble, Gamow and other main historical figures of
the field. It appears that most of the ingredients of the present-day standard
cosmological model, such as the accelation of the expansion due to a repulsive
dark energy, the interpretation of the cosmological constant as vacuum energy
or the possible non-trivial topology of space, had been anticipated by
Lemaitre, although his papers remain desperately unquoted.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:19:41 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Luminet",
"Jean-Pierre",
""
]
] |
0704.3580 | Richard L. Hall | Richard L. Hall and Wolfgang Lucha | Binding energies of semirelativistic N-boson systems | 11 pages | J.Phys.A40:6183-6192,2007 | 10.1088/1751-8113/40/23/012 | CUQM-120, HEPHY-PUB 836/07 | math-ph hep-th math.MP | null | General analytic energy bounds are derived for N-boson systems governed by
semirelativistic Hamiltonians of the form
H=\sum_{i=1}^N \sqrt(p_i^2+m^2) + \sum_{1=i<j}^N V(r_{ij}), where V(r) is a
static attractive pair potential. A translation-invariant model Hamiltonian H_c
is constructed. We conjecture that <H> \ge <H_c> generally, and we prove this
for N=3, and for N=4 when m=0. The conjecture is also valid generally for the
harmonic oscillator and in the nonrelativistic large-m limit. This formulation
allows reductions to scaled 3- or 4-body problems, whose spectral bottoms
provide energy lower bounds. The example of the ultrarelativistic linear
potential is studied in detail and explicit upper- and lower-bound formulas are
derived and compared with earlier bounds.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:33:19 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hall",
"Richard L.",
""
],
[
"Lucha",
"Wolfgang",
""
]
] |
0704.3581 | Santiago Garcia-Burillo | S. Garcia-Burillo, F. Combes, R. Neri, A. Fuente, A. Usero, S. Leon,
J. Lim | Fueling the central engine of radio galaxies. I. The molecular/dusty
disk of 4C 31.04 | 5 pages, 3 figures, Accepted (25/04/2007) in A&A Letters | null | 10.1051/0004-6361:20077599 | null | astro-ph | null | We report the detection of a massive (M(gas) > 5x10^9 Msun) molecular/dusty
disk of 1.4kpc-size fueling the central engine of the Compact Symmetric Object
(CSO) 4C31.04 based on high-resolution (0.5''--1.2'') observations done with
the IRAM Plateau de Bure interferometer (PdBI). These observations allow for
the first time to detect and map the continuum emission from dust at 218GHz in
the disk of a CSO. The case for a massive disk is confirmed by the detection of
strong HCO+(1--0) line emission and absorption. The molecular gas mass of
4C31.04 is in the range 0.5x10^10--5x10^10Msun. While the distribution and
kinematics of the gas correspond roughly to those of a rotating disk, we find
evidence of distortions and non-circular motions suggesting that the disk is
not in a dynamically relaxed state. We discuss the implications of these
results for the general understanding of the evolution of radio galaxies.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:29:47 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Garcia-Burillo",
"S.",
""
],
[
"Combes",
"F.",
""
],
[
"Neri",
"R.",
""
],
[
"Fuente",
"A.",
""
],
[
"Usero",
"A.",
""
],
[
"Leon",
"S.",
""
],
[
"Lim",
"J.",
""
]
] |
0704.3582 | T. Becher | Thomas Becher and Kirill Melnikov | Two-loop QED corrections to Bhabha scattering | 15 pages; minor changes; version to appear in JHEP | JHEP 0706:084,2007 | 10.1088/1126-6708/2007/06/084 | FERMILAB-PUB-07-060-T, UH-511-1103-07 | hep-ph | null | We obtain a simple relation between massless and massive scattering
amplitudes in gauge theories in the limit where all kinematic invariants are
large compared to particle masses. We use this relation to derive the two-loop
QED corrections to large-angle Bhabha scattering.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:42:05 GMT"
},
{
"version": "v2",
"created": "Tue, 1 May 2007 01:13:08 GMT"
},
{
"version": "v3",
"created": "Fri, 29 Jun 2007 20:12:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Becher",
"Thomas",
""
],
[
"Melnikov",
"Kirill",
""
]
] |
0704.3583 | Javier Graci\'a-Carpio | J. Gracia-Carpio (1), P. Planesas (1) and L. Colina (2) ((1) OAN,
Madrid, Spain, (2) IEM, CSIC, Madrid, Spain) | Sub-arcsecond CO(1-0) and CO(2-1) observations of the ultraluminous
infrared galaxy IRAS 10190+1322 | 4 pages, 3 figures. Accepted for publication in A&A Letters Special
Issue for the new extended configuration of the Plateau de Bure
Interferometer | null | 10.1051/0004-6361:20077448 | null | astro-ph | null | We present the results of high resolution mapping of the CO(1-0) and CO(2-1)
emission of the ultraluminous infrared galaxy (ULIRG) IRAS 10190+1322, with the
IRAM interferometer, down to an angular resolution of ~0.3 arcsec. This object
is composed of two interacting galaxies with a projected nuclear separation of
6 kpc, and was selected to analyze the physical and dynamical properties of the
molecular gas in each galaxy in order to study the conditions that lead a
galaxy pair to become ultraluminous in the infrared. With the exception of Arp
220, the closest ULIRG, this is the first time that the CO emission is
morphologically and kinematically resolved in the two interacting galaxies of a
ULIRG system. In one of the galaxies the molecular gas is highly concentrated,
distributed in a circumnuclear disk of 1.7 kpc in size. The molecular gas in
the presumably less infrared luminous galaxy is distributed in a more extended
disk of 7.4 kpc. The molecular gas mass accounts for ~10% of the dynamical mass
in each galaxy. Both objects are rich enough in molecular gas, Mgas ~ 4 10^9
Msun, as to experience an infrared ultraluminous phase.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:30:53 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Gracia-Carpio",
"J.",
""
],
[
"Planesas",
"P.",
""
],
[
"Colina",
"L.",
""
]
] |
0704.3584 | Leslie Hebb | Leslie Hebb, Larry Petro, Holland C. Ford, David R. Ardila, Ignacio
Toledo, Dante Minniti, David A. Golimowski, Mark Clampin | A Search for Planets Transiting the M Dwarf Debris Disk Host, AU
Microscopii | accepted to MNRAS | Mon.Not.Roy.Astron.Soc.379:63-72,2007 | 10.1111/j.1365-2966.2007.11904.x | null | astro-ph | null | We present high cadence, high precision multi-band photometry of the young,
M1Ve, debris disk star, AU Microscopii. The data were obtained in three
continuum filters spanning a wavelength range from 4500\AA to 6600\AA, plus
H$\alpha$, over 28 nights in 2005. The lightcurves show intrinsic stellar
variability due to starspots with an amplitude in the blue band of 0.051
magnitudes and a period of 4.847 days. In addition, three large flares were
detected in the data which all occur near the minimum brightness of the star.
We remove the intrinsic stellar variability and combine the lightcurves of all
the filters in order to search for transits by possible planetary companions
orbiting in the plane of the nearly edge-on debris disk. The combined final
lightcurve has a sampling of 0.35 minutes and a standard deviation of 6.8
millimags (mmag). We performed Monte Carlo simulations by adding fake transits
to the observed lightcurve and find with 95% significance that there are no
Jupiter mass planets orbiting in the plane of the debris disk on circular
orbits with periods, P $\le 5$ days. In addition, there are no young
Neptune-like planets (with radii 2.5$\times$ smaller than the young Jupiter) on
circular orbits with periods, P $\le 3$ days.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:05:11 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Hebb",
"Leslie",
""
],
[
"Petro",
"Larry",
""
],
[
"Ford",
"Holland C.",
""
],
[
"Ardila",
"David R.",
""
],
[
"Toledo",
"Ignacio",
""
],
[
"Minniti",
"Dante",
""
],
[
"Golimowski",
"David A.",
""
],
[
"Clampin",
"Mark",
""
]
] |
0704.3585 | Massimiliano Procura | Wolfram Weise, Claudia Ratti and Simon Roessner | Phases of QCD, Polyakov Loop and Quasiparticles | 9 pages, 8 figures. To appear in Proceedings YKIS2006, Prog. Theor.
Phys. Suppl. (Kyoto) | Prog.Theor.Phys.Suppl.168:435-443,2007 | 10.1143/PTPS.168.435 | TUM/T39-07-08, ECT*-07-09 | hep-ph | null | QCD thermodynamics is studied using a model which combines Polyakov loop
dynamics with spontaneous chiral symmetry breaking and its restoration (the
PNJL model). The input is fixed entirely by pure-gauge lattice QCD results and
by pion properties in vacuum. Successful comparisons with results from thermal
lattice QCD are achieved, including extrapolations to finite quark chemical
potential. The phase diagram and selected susceptibilities for two quark
flavors are investigated with inclusion of diquark degrees of freedom.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:51:16 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Weise",
"Wolfram",
""
],
[
"Ratti",
"Claudia",
""
],
[
"Roessner",
"Simon",
""
]
] |
0704.3586 | Matthias Staudacher | A.V. Kotikov, L.N. Lipatov, A. Rej, M. Staudacher and V.N. Velizhanin | Dressing and Wrapping | 20 pages, 2 tables, no figures; v2: references added, conjecture on
exact four-loop twist-two result stated | J.Stat.Mech.0710:P10003,2007 | 10.1088/1742-5468/2007/10/P10003 | AEI-2007-024 | hep-th hep-ph | null | We prove that the validity of the recently proposed dressed, asymptotic Bethe
ansatz for the planar AdS/CFT system is indeed limited at weak coupling by
operator wrapping effects. This is done by comparing the Bethe ansatz
predictions for the four-loop anomalous dimension of finite-spin twist-two
operators to BFKL constraints from high-energy scattering amplitudes in N=4
gauge theory. We find disagreement, which means that the ansatz breaks down for
length-two operators at four-loop order. Our method supplies precision tools
for multiple all-loop tests of the veracity of any yet-to-be constructed set of
exact spectral equations. Finally we present a conjecture for the exact
four-loop anomalous dimension of the family of twist-two operators, which
includes the Konishi field.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:11:24 GMT"
},
{
"version": "v2",
"created": "Wed, 4 Jul 2007 19:07:16 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kotikov",
"A. V.",
""
],
[
"Lipatov",
"L. N.",
""
],
[
"Rej",
"A.",
""
],
[
"Staudacher",
"M.",
""
],
[
"Velizhanin",
"V. N.",
""
]
] |
0704.3587 | Roberto Galv\'an-Madrid | Roberto Galv\'an-Madrid (1), Enrique V\'azquez-Semadeni (1), Jongsoo
Kim (2) and Javier Ballesteros-Paredes (1). ((1) Centro de Radioastronom\'ia
y Astrof\'isica. UNAM. (2) Korea Astronomy and Space Science Institute.) | Statistics of Core Lifetimes in Numerical Simulations of Turbulent,
Magnetically Supercritical Molecular Clouds | 25 pages, 8 figures, ApJ accepted. Fig.1 animation is at
http://www.astrosmo.unam.mx/~e.vazquez/turbulence/movies/Galvan_etal07/Galvan_etal07.html | null | 10.1086/522081 | null | astro-ph | null | We present measurements of the mean dense core lifetimes in numerical
simulations of magnetically supercritical, turbulent, isothermal molecular
clouds, in order to compare with observational determinations. "Prestellar"
lifetimes (given as a function of the mean density within the cores, which in
turn is determined by the density threshold n_thr used to define them) are
consistent with observationally reported values, ranging from a few to several
free-fall times. We also present estimates of the fraction of cores in the
"prestellar", "stellar'', and "failed" (those cores that redisperse back into
the environment) stages as a function of n_thr. The number ratios are measured
indirectly in the simulations due to their resolution limitations. Our approach
contains one free parameter, the lifetime of a protostellar object t_yso (Class
0 + Class I stages), which is outside the realm of the simulations. Assuming a
value t_yso = 0.46 Myr, we obtain number ratios of starless to stellar cores
ranging from 4-5 at n_thr = 1.5 x 10^4 cm^-3 to 1 at n_thr = 1.2 x 10^5 cm^-3,
again in good agreement with observational determinations. We also find that
the mass in the failed cores is comparable to that in stellar cores at n_thr =
1.5 x 10^4 cm^-3, but becomes negligible at n_thr = 1.2 x 10^5 cm^-3, in
agreement with recent observational suggestions that at the latter densities
the cores are in general gravitationally dominated. We conclude by noting that
the timescale for core contraction and collapse is virtually the same in the
subcritical, ambipolar diffusion-mediated model of star formation, in the model
of star formation in turbulent supercritical clouds, and in a model
intermediate between the previous two, for currently accepted values of the
clouds' magnetic criticality.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:19:05 GMT"
},
{
"version": "v2",
"created": "Wed, 8 Aug 2007 19:13:11 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Galván-Madrid",
"Roberto",
""
],
[
"Vázquez-Semadeni",
"Enrique",
""
],
[
"Kim",
"Jongsoo",
""
],
[
"Ballesteros-Paredes",
"Javier",
""
],
[
".",
"",
""
]
] |
0704.3588 | Cristina Comaniciu | Cristina Comaniciu and H. Vincent Poor | On Energy Efficient Hierarchical Cross-Layer Design: Joint Power Control
and Routing for Ad Hoc Networks | To appear in the EURASIP Journal on Wireless Communications and
Networking, Special Issue on Wireless Mobile Ad Hoc Networks | null | null | null | cs.IT math.IT | null | In this paper, a hierarchical cross-layer design approach is proposed to
increase energy efficiency in ad hoc networks through joint adaptation of
nodes' transmitting powers and route selection. The design maintains the
advantages of the classic OSI model, while accounting for the cross-coupling
between layers, through information sharing. The proposed joint power control
and routing algorithm is shown to increase significantly the overall energy
efficiency of the network, at the expense of a moderate increase in complexity.
Performance enhancement of the joint design using multiuser detection is also
investigated, and it is shown that the use of multiuser detection can increase
the capacity of the ad hoc network significantly for a given level of energy
consumption.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 16:33:55 GMT"
}
] | 2007-07-13T00:00:00 | [
[
"Comaniciu",
"Cristina",
""
],
[
"Poor",
"H. Vincent",
""
]
] |
0704.3589 | Lee Anne Willson | L. A. Willson | What do we really know about mass loss on the AGB? | Conference: Why do Galaxies care about AGB stars? Vienna 2006.
Editors Franz Kerschbaum, Corinne Charbonnel, and Bob Wing | null | null | null | astro-ph | null | Mass loss rate formulae are derived from observations or from suites of
models. For theoretical models, the following have all been identified as
factors greatly influencing the atmospheric structure and mass loss rates:
Pulsation with piston amplitude scaling appropriately with stellar L; dust
nucleation and growth, with radiation pressure and grain-gas interactions and
appropriate dependence on temperature and density; non-grey opacity with at
least 51 frequency samples; non-LTE and departures from radiative equilibrium
in the compressed and expanding flows; and non-equilibrium processes affecting
the composition (grain formation; molecular chemistry). No one set of models
yet includes all the factors known to be important. In fact, it is very
difficult to construct a model that can simultaneously include these factors
and be useful for computing spectra. Therefore, although theoretical model
grids are needed to separate the effects of M,L,R and/or $T_{\mathrm{eff}}$ or
Z on the mass loss rates, these models must be carefully checked against
observations. Getting the right order of magnitude for the mass loss rate is
only the first step in such a comparison, and is not sufficient to determine
whether the mass loss formula is correct. However, there are observables that
do test the validity of mass loss formulae as they depend directly on $d\log
\dot M/d\log L$, $d\log \dot M/d\log R$, or $d\log \dot M/d\log P$.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:44:59 GMT"
}
] | 2009-04-16T00:00:00 | [
[
"Willson",
"L. A.",
""
]
] |
0704.3590 | Gerard Le Caer | C. Male, G. Le Caer and R. Delannay | Spectral fluctuations of tridiagonal random matrices from the
beta-Hermite ensemble | 35 pages, 10 figures, corresponding author: G. Le Caer | null | 10.1103/PhysRevE.76.042101 | null | cond-mat.stat-mech | null | A time series delta(n), the fluctuation of the nth unfolded eigenvalue was
recently characterized for the classical Gaussian ensembles of NxN random
matrices (GOE, GUE, GSE). It is investigated here for the beta-Hermite ensemble
as a function of beta (zero or positive) by Monte Carlo simulations. The
fluctuation of delta(n) and the autocorrelation function vary logarithmically
with n for any beta>0 (1<<n<<N). The simple logarithmic behavior reported for
the higher-order moments of delta(n) for the GOE (beta=1) and the GUE (beta=2)
is valid for any positive beta and is accounted for by Gaussian distributions
whose variances depend linearly on ln(n). The 1/f noise previously demonstrated
for delta(n) series of the three Gaussian ensembles, is characterized by
wavelet analysis both as a function of beta and of N. When beta decreases from
1 to 0, for a given and large enough N, the evolution from a 1/f noise at
beta=1 to a 1/f^2 noise at beta=0 is heterogeneous with a ~1/f^2 noise at the
finest scales and a ~1/f noise at the coarsest ones. The range of scales in
which a ~1/f^2 noise predominates grows progressively when beta decreases.
Asymptotically, a 1/f^2 noise is found for beta=0 while a 1/f noise is the rule
for beta positive.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:02:51 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Male",
"C.",
""
],
[
"Caer",
"G. Le",
""
],
[
"Delannay",
"R.",
""
]
] |
0704.3591 | Peyman Razaghi | Marko Aleksic, Peyman Razaghi, Wei Yu | Capacity of a Class of Modulo-Sum Relay Channels | To be presented in IEEE Int. Symp. on Inform. Theory (ISIT) 2007 | null | null | null | cs.IT math.IT | null | This paper characterizes the capacity of a class of modulo additive noise
relay channels, in which the relay observes a corrupted version of the noise
and has a separate channel to the destination. The capacity is shown to be
strictly below the cut-set bound in general and achievable using a
quantize-and-forward strategy at the relay. This result confirms a conjecture
by Ahlswede and Han about the capacity of channels with rate limited state
information at the destination for this particular class of channels.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:13:17 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Aleksic",
"Marko",
""
],
[
"Razaghi",
"Peyman",
""
],
[
"Yu",
"Wei",
""
]
] |
0704.3592 | Gerhard Hensler | W. Vieser (1,2), G. Hensler (1)((1)Institute of Astronomy Vienna,
(2)Christoph-Probst-Gymnasium Gilching) | The evolution of interstellar clouds in a streaming hot plasma including
heat conduction | 19 pages, 12 figures, accepted in Astronomy and Astrophysics | null | 10.1051/0004-6361:20042120 | null | astro-ph | null | To examine the evolution of giant molecular clouds in the stream of a hot
plasma we performed two-dimensional hydrodynamical simulations that take full
account of self-gravity, heating and cooling effects and heat conduction by
electrons. We use the thermal conductivity of a fully ionized hydrogen plasma
proposed by Spitzer and a saturated heat flux according to Cowie & McKee in
regions where the mean free path of the electrons is large compared to the
temperature scaleheight. Significant structural and evolutionary differences
occur between simulations with and without heat conduction. Dense clouds in
pure dynamical models experience dynamical destruction by Kelvin-Helmholtz (KH)
instability. In static models heat conduction leads to evaporation of such
clouds. Heat conduction acting on clouds in a gas stream smooths out steep
temperature and density gradients at the edge of the cloud because the
conduction timescale is shorter than the cooling timescale. This diminishes the
velocity gradient between the streaming plasma and the cloud, so that the
timescale for the onset of KH instabilities increases, and the surface of the
cloud becomes less susceptible to KH instabilities. The stabilisation effect of
heat conduction against KH instability is more pronounced for smaller and less
massive clouds. As in the static case more realistic cloud conditions allow
heat conduction to transfer hot material onto the cloud's surface and to mix
the accreted gas deeper into the cloud.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 19:13:55 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Vieser",
"W.",
""
],
[
"Hensler",
"G.",
""
]
] |
0704.3593 | Kalanand Mishra | BABAR Collaboration, B. Aubert, et al | Amplitude Analysis of the decay D^0 --> K^- K^+ pi^0 | 8 pages, 10 postscript figues, submitted to Physical Review D (Rapid
Communications) | Phys.Rev.D76:011102,2007 | 10.1103/PhysRevD.76.011102 | BABAR-PUB-07/022, SLAC-PUB-12416 | hep-ex | null | Using 385 fb^-1 of e^+e^- collisions at the CM energies of around 10.6 GeV
recorded by the BaBar experiment, we study the amplitudes of the singly
Cabibbo-suppressed decay D^0 --> K^- K^+ pi^0. We measure the strong phase
difference between the D0bar and D0 decays to the K^*(892)^+ K^- state to be
-35.5 +/- 1.9 (stat) +/- 2.2 (syst) degrees, and their amplitude ratio to be
0.599 +/- 0.013 (stat) +/- 0.011 (syst). We observe significant contributions
from the Kpi and K^-K^+ scalar and vector amplitudes, and analyze the moments
of the cosine of the helicity angle in these systems. We find no evidence for
charged, scalar kappa(800) state, nor for higher spin states. We also perform a
model-independent partial wave analysis of the K^-K^+ system in a limited mass
range around 1 GeV/c^2. We study several models for Kpi S-wave amplitude, and
describe which one is favored by our data.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:17:33 GMT"
},
{
"version": "v2",
"created": "Wed, 11 Jul 2007 20:20:28 GMT"
}
] | 2010-04-12T00:00:00 | [
[
"BABAR Collaboration",
"",
""
],
[
"Aubert",
"B.",
""
]
] |
0704.3594 | Olaf Behnke | H1 Collaboration | Search for Baryonic Resonances Decaying to Xi pi in Deep-Inelastic
Scattering at HERA | 15 pages, 4 figures | Eur.Phys.J.C52:507-514,2007 | 10.1140/epjc/s10052-007-0407-3 | DESY 07-045 | hep-ex | null | A search for narrow baryonic resonances decaying into Xi- pi- or Xi- pi+ and
their antiparticles is carried out with the H1 detector using deep inelastic
scattering events at HERA in the range of negative photon four-momentum
transfer squared 2 < Q^2 < 100 GeV^2. No signal is observed for a new baryonic
state in the mass range 1600 - 2300 MeV in either the doubly charged or the
neutral decay channels. The known baryon Xi0 is observed through its decay mode
into Xi- pi+. Upper limits are given on the ratio of the production rates of
new baryonic states, such as the hypothetical pentaquark states Xi^{--}_{5q} or
Xi^{0}_{5q}, relative to the Xi0 baryon state.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:37:42 GMT"
}
] | 2012-08-27T00:00:00 | [
[
"H1 Collaboration",
"",
""
]
] |
0704.3595 | Eyo Ita III | Eyo Eyo Ita III | 4-Dimensional General Relativity from the instrinsic spatial geometry of
SO(3) Yang--Mills theory | 16 pages. Background material for revised journal article | Nucl. Phys. B, Vol. 852 (2011) pp.681-695 | 10.1016/j.nuclphysb.2011.07.004 | DAMTP-2007-38 | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we derive 4-dimensional General Relativity from three
dimensions, using the intrinsic spatial geometry inherent in Yang--Mills theory
which has been exposed by previous authors as well as as some properties of the
Ashtekar variables. We provide various interesting relations, including the
fact that General Relativity can be written as a Yang--Mills theory where the
antiself-dual Weyl curvature replaces the Yang--Mills coupling constant. We
have generalized the results of some previous authors, covering Einsteins
spaces, to include more general spacetime geometries.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:48:59 GMT"
},
{
"version": "v2",
"created": "Mon, 30 Apr 2007 05:07:12 GMT"
},
{
"version": "v3",
"created": "Wed, 15 Dec 2010 20:53:57 GMT"
},
{
"version": "v4",
"created": "Fri, 18 Mar 2011 06:45:03 GMT"
},
{
"version": "v5",
"created": "Thu, 22 Sep 2011 01:41:48 GMT"
}
] | 2012-02-20T00:00:00 | [
[
"Ita",
"Eyo Eyo",
"III"
]
] |
0704.3596 | Lun-Shin Yao | Lun-Shin Yao, Dan Hughes | Comment on "Time Step Sensitivity of Nonlinear Atmospheric Models:
Numerical Convergence, Truncation Error Growth, and Ensemble Design" Teixeira
et al. (2007) | 3 pages | null | 10.1175/2007JAS2495.1 | null | nlin.CD | null | Comment on "Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical
Convergence, Truncation Error Growth, and Ensemble Design" Teixeira et al.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 17:51:03 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Yao",
"Lun-Shin",
""
],
[
"Hughes",
"Dan",
""
]
] |
0704.3597 | Brenda Frye | B. L. Frye (1), D. Coe (2), D. V. Bowen (3), N. Benitez (2), T.
Broadhurst (4), P. Guhathakurta (5), G. Illingworth (5), F. Menanteau (6), K.
Sharon (4), R. Lupton (3), G. Meylan (7), K. Zekser (8), G. Meurer (8), and
M. Hurley (1) ((1) DCU; (2) CSIC; (3) Princeton University; (4) TAU; (5)
UCSC; (6) Rutgers University; (7) EPFL Observatoire; (8) JHU) | The Sextet Arcs: a Strongly Lensed Lyman Break Galaxy in the ACS
Spectroscopic Galaxy Survey towards Abell 1689 | Accepted for publication in ApJ | Astrophys.J.665:921-935,2007 | 10.1086/519244 | null | astro-ph | null | We present results of the HST Advanced Camera for Surveys spectroscopic
ground-based redshift survey in the field of A1689. We measure 98 redshifts,
increasing the number of spectroscopically confirmed objects by sixfold. We
present two spectra from this catalog of the Sextet Arcs, images which arise
from a strongly-lensed Lyman Break Galaxy (LBG) at a redshift of z=3.038.
Gravitational lensing by the cluster magnifies its flux by a factor of ~16 and
produces six separate images with a total r-band magnitude of r_625=21.7. The
two spectra, each of which represents emission from different regions of the
LBG, show H I and interstellar metal absorption lines at the systemic redshift.
Significant variations are seen in Ly-alpha profile across a single galaxy,
ranging from strong absorption to a combination of emission plus absorption. A
spectrum of a third image close to the brightest arc shows Ly-alpha emission at
the same redshift as the LBG, arising from either another spatially distinct
region of the galaxy, or from a companion galaxy close to the LBG. Taken as a
group, the Ly-alpha equivalent width in these three spectra decreases with
increasing equivalent width of the strongest interstellar absorption lines. We
discuss how these variations can be used to understand the physical conditions
in the LBG. Intrinsically, this LBG is faint, ~0.1L*, and forming stars at a
modest rate, ~4 solar masses per year. We also detect absorption line systems
toward the Sextet Arcs at z=2.873 and z=2.534. The latter system is seen across
two of our spectra.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 19:34:31 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Frye",
"B. L.",
""
],
[
"Coe",
"D.",
""
],
[
"Bowen",
"D. V.",
""
],
[
"Benitez",
"N.",
""
],
[
"Broadhurst",
"T.",
""
],
[
"Guhathakurta",
"P.",
""
],
[
"Illingworth",
"G.",
""
],
[
"Menanteau",
"F.",
""
],
[
"Sharon",
"K.",
""
],
[
"Lupton",
"R.",
""
],
[
"Meylan",
"G.",
""
],
[
"Zekser",
"K.",
""
],
[
"Meurer",
"G.",
""
],
[
"Hurley",
"M.",
""
]
] |
0704.3598 | Fabricio Macedo de Souza | F. M. Souza, S. A. Leao, R. M. Gester, and A. P. Jauho | Transient Charging and Discharging of Spin-polarized Electrons in a
Quantum Dot | 7 pages, 6 figures. Typos corrections corresponding to the published
version | Phys. Rev. B 76, 125318 (2007) | 10.1103/PhysRevB.76.125318 | null | cond-mat.mes-hall | null | We study spin-polarized transient transport in a quantum dot coupled to two
ferromagnetic leads subjected to a rectangular bias voltage pulse.
Time-dependent spin-resolved currents, occupations, spin accumulation, and
tunneling magnetoresistance (TMR) are calculated using both nonequilibrium
Green function and master equation techniques. Both parallel and antiparallel
leads' magnetization alignments are analyzed. Our main findings are: a
dynamical spin accumulation that changes sign in time, a short-lived pulse of
spin polarized current in the emitter lead (but not in the collector lead), and
a dynamical TMR that develops negative values in the transient regime. We also
observe that the intra-dot Coulomb interaction can enhance even further the
negative values of the TMR.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 18:06:07 GMT"
},
{
"version": "v2",
"created": "Fri, 28 Sep 2007 12:27:20 GMT"
}
] | 2011-11-09T00:00:00 | [
[
"Souza",
"F. M.",
""
],
[
"Leao",
"S. A.",
""
],
[
"Gester",
"R. M.",
""
],
[
"Jauho",
"A. P.",
""
]
] |
0704.3599 | Brant M. Johnson | PHENIX Collaboration, A. Adare, et al | Inclusive cross section and double helicity asymmetry for \pi^0
production in p+p collisions at sqrt(s)=200 GeV: Implications for the
polarized gluon distribution in the proton | 375 authors, 7 pages, 3 figures. Submitted to Phys. Rev. D, Rapid
Communications. Plain text data tables for the points plotted in figures for
this and previous PHENIX publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.html | Phys.Rev.D76:051106,2007 | 10.1103/PhysRevD.76.051106 | null | hep-ex | null | The PHENIX experiment presents results from the RHIC 2005 run with polarized
proton collisions at sqrt(s)=200 GeV, for inclusive \pi^0 production at
mid-rapidity. Unpolarized cross section results are given for transverse
momenta p_T=0.5 to 20 GeV/c, extending the range of published data to both
lower and higher p_T. The cross section is described well for p_T < 1 GeV/c by
an exponential in p_T, and, for p_T > 2 GeV/c, by perturbative QCD. Double
helicity asymmetries A_LL are presented based on a factor of five improvement
in uncertainties as compared to previously published results, due to both an
improved beam polarization of 50%, and to higher integrated luminosity. These
measurements are sensitive to the gluon polarization in the proton, and exclude
maximal values for the gluon polarization.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 18:31:40 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"PHENIX Collaboration",
"",
""
],
[
"Adare",
"A.",
""
]
] |
0704.3600 | Alexander Korzenev | A. Korzenev (for the COMPASS collaboration) | Valence Quarks Polarization from COMPASS | Talk given on XV Internetional Workshop on Deep-Inelastic Scattering
and Related Subjects, April 16-20, 2007, Munich, Germany | null | null | null | hep-ex | null | A first evaluation of the polarized valence quark distribution $\Delta
u_v(x)+\Delta d_v(x)$ from the COMPASS experiment (CERN/SPS) is presented. The
data were collected by COMPASS in the years 2002--2004 using a 160 GeV
polarized muon beam scattered off a large polarized $^6$LiD target and cover
the range $1< Q^2 < 100$ GeV$^2$ and $0.006<x<0.7$. The analysis is based on
the difference asymmetry, $A^{h^+ - h^-}$, for hadrons of opposite charges,
which gives a direct access to the polarization of valence quarks.
| [
{
"version": "v1",
"created": "Thu, 26 Apr 2007 18:25:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Korzenev",
"A.",
"",
"for the COMPASS collaboration"
]
] |
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