id
stringlengths 9
16
| submitter
stringlengths 1
64
⌀ | authors
stringlengths 3
36.7k
| title
stringlengths 1
382
| comments
stringlengths 1
1.15k
⌀ | journal-ref
stringlengths 1
557
⌀ | doi
stringlengths 7
153
⌀ | report-no
stringlengths 1
479
⌀ | categories
stringlengths 5
125
| license
stringclasses 9
values | abstract
stringlengths 6
6.09k
| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0707.1530 | Hongki Min | Hongki Min, Giovanni Borghi, Marco Polini, A.H. MacDonald | Pseudospin Magnetism in Graphene | 5 pages, 4 figures; added figure 1, modified introduction and
discussion; updated references | Phys. Rev. B 77, 041407(R) (2008) | 10.1103/PhysRevB.77.041407 | null | cond-mat.str-el | null | We predict that neutral graphene bilayers are pseudospin magnets in which the
charge density-contribution from each valley and spin spontaneously shifts to
one of the two layers. The band structure of this system is characterized by a
momentum-space vortex which is responsible for unusual competition between band
and kinetic energies leading to symmetry breaking in the vortex core. We
discuss the possibility of realizing a pseudospin version of ferromagnetic
metal spintronics in graphene bilayers based on hysteresis associated with this
broken symmetry.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 21:40:56 GMT"
},
{
"version": "v2",
"created": "Wed, 17 Oct 2007 19:07:33 GMT"
},
{
"version": "v3",
"created": "Fri, 18 Jan 2008 01:18:36 GMT"
}
] | 2008-01-18T00:00:00 | [
[
"Min",
"Hongki",
""
],
[
"Borghi",
"Giovanni",
""
],
[
"Polini",
"Marco",
""
],
[
"MacDonald",
"A. H.",
""
]
] |
0707.1531 | Mayeul d'Avezac | Mayeul d'Avezac and Nicola Marzari and Francesco Mauri | Spin and orbital magnetic response in metals: susceptibility and NMR
shifts | null | null | 10.1103/PhysRevB.76.165122 | null | cond-mat.mtrl-sci | null | A DFT-based method is presented which allows the computation of all-electron
NMR shifts of metallic compounds with periodic boundary conditions. NMR shifts
in metals measure two competing physical phenomena. Electrons interact with the
applied magnetic field (i) as magnetic dipoles (or spins), resulting in the
Knight shift, (ii) as moving electric charges, resulting in the chemical (or
orbital) shift. The latter is treated through an extension to metals of the
Gauge Invariant Projector Augment Wave(GIPAW) developed for insulators. The
former is modeled as the hyperfine interaction between the electronic spin
polarization and the nuclear dipoles. NMR shifts are obtained with respect to
the computed shieldings of reference compounds, yielding fully ab-initio
quantities which are directly comparable to experiment. The method is validated
by comparing the magnetic susceptibility of interacting and non-interacting
homogeneous gas with known analytical results, and by comparing the computed
NMR shifts of simple metals with experiment.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 21:51:18 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"d'Avezac",
"Mayeul",
""
],
[
"Marzari",
"Nicola",
""
],
[
"Mauri",
"Francesco",
""
]
] |
0707.1532 | Samantha Riesenfeld | Constantinos Daskalakis (1), Richard M. Karp (1), Elchanan Mossel (1),
Samantha Riesenfeld (1), Elad Verbin (2) ((1) U.C. Berkeley, (2) Tel Aviv
University) | Sorting and Selection in Posets | 24 pages | null | null | null | cs.DS cs.DM | null | Classical problems of sorting and searching assume an underlying linear
ordering of the objects being compared. In this paper, we study a more general
setting, in which some pairs of objects are incomparable. This generalization
is relevant in applications related to rankings in sports, college admissions,
or conference submissions. It also has potential applications in biology, such
as comparing the evolutionary fitness of different strains of bacteria, or
understanding input-output relations among a set of metabolic reactions or the
causal influences among a set of interacting genes or proteins. Our results
improve and extend results from two decades ago of Faigle and Tur\'{a}n.
A measure of complexity of a partially ordered set (poset) is its width. Our
algorithms obtain information about a poset by queries that compare two
elements. We present an algorithm that sorts, i.e. completely identifies, a
width w poset of size n and has query complexity O(wn + nlog(n)), which is
within a constant factor of the information-theoretic lower bound. We also show
that a variant of Mergesort has query complexity O(wn(log(n/w))) and total
complexity O((w^2)nlog(n/w)). Faigle and Tur\'{a}n have shown that the sorting
problem has query complexity O(wn(log(n/w))) but did not address its total
complexity.
For the related problem of determining the minimal elements of a poset, we
give efficient deterministic and randomized algorithms with O(wn) query and
total complexity, along with matching lower bounds for the query complexity up
to a factor of 2. We generalize these results to the k-selection problem of
determining the elements of height at most k. We also derive upper bounds on
the total complexity of some other problems of a similar flavor.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 21:52:17 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Daskalakis",
"Constantinos",
""
],
[
"Karp",
"Richard M.",
""
],
[
"Mossel",
"Elchanan",
""
],
[
"Riesenfeld",
"Samantha",
""
],
[
"Verbin",
"Elad",
""
]
] |
0707.1533 | Hugo Martel | Paramita Barai, William Brito, and Hugo Martel | The Fate of Dwarf Galaxies in Clusters and the Origin of Intracluster
Stars. I. Isolated Clusters | 21 pages, submitted to Journal of Astrophysics and Astronomy | null | null | null | astro-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The main goal of this paper is to compare the relative importance of
destruction by tides, vs. destruction by mergers, in order to assess if tidal
destruction of dwarf galaxies in clusters is a viable scenario for explaining
the origin of intracluster stars. We have designed a simple algorithm for
simulating the evolution of isolated clusters. The distribution of galaxies in
the cluster is evolved using a direct gravitational N-body algorithm combined
with a subgrid treatment of physical processes such as mergers, tidal
disruption, and galaxy harassment. Using this algorithm, we have performed a
total of 227 simulations. Our main results are (1) destruction of dwarf
galaxies by mergers dominates over destruction by tides, and (2) the
destruction of dwarf galaxies by tides is sufficient to explain the observed
intracluster light in clusters.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 21:59:18 GMT"
},
{
"version": "v2",
"created": "Wed, 2 Jul 2008 19:34:39 GMT"
}
] | 2008-07-02T00:00:00 | [
[
"Barai",
"Paramita",
""
],
[
"Brito",
"William",
""
],
[
"Martel",
"Hugo",
""
]
] |
0707.1534 | Kamel Aouiche | J\'er\^ome Darmont, Omar Boussaid, Jean-Christian Ralaivao and Kamel
Aouiche | An Architecture Framework for Complex Data Warehouses | null | null | null | null | cs.DB | null | Nowadays, many decision support applications need to exploit data that are
not only numerical or symbolic, but also multimedia, multistructure,
multisource, multimodal, and/or multiversion. We term such data complex data.
Managing and analyzing complex data involves a lot of different issues
regarding their structure, storage and processing, and metadata are a key
element in all these processes. Such problems have been addressed by classical
data warehousing (i.e., applied to "simple" data). However, data warehousing
approaches need to be adapted for complex data. In this paper, we first propose
a precise, though open, definition of complex data. Then we present a general
architecture framework for warehousing complex data. This architecture heavily
relies on metadata and domain-related knowledge, and rests on the XML language,
which helps storing data, metadata and domain-specific knowledge altogether,
and facilitates communication between the various warehousing processes.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 22:01:40 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Darmont",
"Jérôme",
""
],
[
"Boussaid",
"Omar",
""
],
[
"Ralaivao",
"Jean-Christian",
""
],
[
"Aouiche",
"Kamel",
""
]
] |
0707.1535 | Alexander Lenz | Alexander Lenz | Unparticle physics effects in B_s mixing | 12 pages, 4 figures, typos corrected, references added | Phys.Rev.D76:065006,2007 | 10.1103/PhysRevD.76.065006 | null | hep-ph hep-ex | null | We investigate unparticle effects in B_s mixing. In particular we discuss the
possibility of reproducing the experimental result of \Delta M_s, while having
large effects on the mixing phase \phi_s, which might be visible in current
experiments.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 22:17:46 GMT"
},
{
"version": "v2",
"created": "Tue, 17 Jul 2007 10:26:44 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Lenz",
"Alexander",
""
]
] |
0707.1536 | Michael E. Peskin | Michael E. Peskin | Dark Matter and Particle Physics | 13 pages, 5 figures; minor typo corrections | J.Phys.Soc.Jap.76:111017,2007 | 10.1143/JPSJ.76.111017 | SLAC-PUB-12493 | hep-ph astro-ph | null | [A brief review intended for a general physics colloquium audience.]
Astrophysicists now know that 80% of the matter in the universe is `dark
matter', composed of neutral and weakly interacting elementary particles that
are not part of the Standard Model of particle physics. I will summarize the
evidence for dark matter. I will explain why I expect dark matter particles to
be produced at the CERN LHC. We will then need to characterize the new weakly
interacting particles and demonstrate that they are the same particles that are
found in the cosmos. I will describe how this might be done.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 23:01:52 GMT"
},
{
"version": "v2",
"created": "Sun, 29 Jul 2007 23:48:46 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Peskin",
"Michael E.",
""
]
] |
0707.1537 | Masanori Nakamura | Masanori Nakamura, Hui Li, Steven Diehl, Shengtai Li (LANL) | Numerical Modeling of AGN Jets: Formation of Magnetically Dominated
Lobes and Stability Properties of Current-carrying Jets | 5 pages; to appear in "Extragalactic Jets: Theory and Observation
from Radio to Gamma Ray", eds. T. A. Rector and D. S. De Young, ASP
conference series | null | null | LA-UR-06-4099, LA-UR-06-4688 | astro-ph | null | We argue the behavior of Poynting flux-dominated outflows from AGN in the
galactic cluster systems by performing three-dimensional MHD simulations within
the framework of the "magnetic tower" model. Of particular interests are the
structure of MHD waves, the cylindrical radial force balance, the
(de)collimation, and the stability properties of magnetic tower jets.
Transition between the jet/lobe and the formation of wiggling jet by growing
current-driven instability are discussed.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 23:23:36 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Nakamura",
"Masanori",
"",
"LANL"
],
[
"Li",
"Hui",
"",
"LANL"
],
[
"Diehl",
"Steven",
"",
"LANL"
],
[
"Li",
"Shengtai",
"",
"LANL"
]
] |
0707.1538 | Sang-Hoon Kim | Sang-Hoon Kim | Transition temperature of the homogeneous and dilute Bose gas in
D-dimensions | 4 pages, 2 figure | null | null | null | cond-mat.stat-mech | null | The phase transition temperature of the homogeneous and dilute Bose gas in
D-dimensions ($2 \le D \le 3$) is calculated by a mean field-based statistical
method. The shift of the phase transition temperature is written up to the
leading order as $\Delta T_c/T_c^0 = c \gam^{\al}$, where $\gam=n^{1/3}a$.
We derived Huang's result of the phase transition temperature in the
generalized dimensions. We show that $ c(D)$ is positive and
$\al(D)=2(D/2-1)^2$ in the short-wavelength range. The origin of the difference
between $\al=1/2$ and $\al=1$ at D=3 is discussed. The $T_c$ at D=2 is
calculated in the same scheme. The result is compared with Fisher and
Hohenberg's KT temperature.
| [
{
"version": "v1",
"created": "Tue, 10 Jul 2007 23:48:25 GMT"
},
{
"version": "v2",
"created": "Mon, 23 Jul 2007 00:58:10 GMT"
},
{
"version": "v3",
"created": "Tue, 11 Dec 2007 06:28:45 GMT"
}
] | 2007-12-11T00:00:00 | [
[
"Kim",
"Sang-Hoon",
""
]
] |
0707.1539 | William Heinzer | Jebrel M. Habeb, Mowaffaq Hajja and William J. Heinzer | Conjugacy classes and invariant subrings of R-automorphisms of R[x] | 30 pages | null | null | null | math.AC | null | We consider the group G of R-automorphisms of the polynomial ring R[x]
especially in the case where R is the ring of integers modulo n. We describe
conjugacy classes in G, and in the case where n = 4, we describe more
explicitly the structure of G and determine all rings of invariants of R[x]
with respect to subgroups of G.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 00:05:05 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Habeb",
"Jebrel M.",
""
],
[
"Hajja",
"Mowaffaq",
""
],
[
"Heinzer",
"William J.",
""
]
] |
0707.1540 | Albert Fannjiang | Albert C. Fannjiang | Two-Frequency Radiative Transfer. II: Maxwell Equations in Random
Dielectrics | Change certain notations throughout the paper | Journal of Optical Society of America A (2007) | 10.1364/JOSAA.24.003680 | null | physics.optics | null | The paper addresses the space-frequency correlations of electromagnetic waves
in general random, bi-anisotropic media whose constitutive tensors are complex
Hermitian matrices. The two-frequency Wigner distribution (2f-WD) for polarized
waves is introduced to describe the space-frequency correlations and the closed
form Wigner-Moyal equation is derived from the Maxwell equations. Two-frequency
radiative transfer (2f-RT) equations is then derived from the Wigner-Moyal
equation by using the multiple scale expansion. For the simplest isotropic
medium, the result coincides with Chandrasekhar's transfer equation. In
birefringent media, the 2f-RT equations take the scalar form due to the absence
of depolarization. A number of birefringent media such as the chiral, uniaxial
and gyrotropic media are examined. For the unpolarized wave in the isotropic
medium the 2f-RT equations reduces to the Fokker-Planck equation previously
derived in Part I. A similar Fokker-Planck equation is derived from the scalar
2f-RT equation for the birefringent media.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 00:39:53 GMT"
},
{
"version": "v2",
"created": "Tue, 14 Aug 2007 23:53:33 GMT"
},
{
"version": "v3",
"created": "Fri, 17 Aug 2007 00:03:51 GMT"
},
{
"version": "v4",
"created": "Wed, 29 Aug 2007 22:33:39 GMT"
},
{
"version": "v5",
"created": "Mon, 1 Oct 2007 16:12:33 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Fannjiang",
"Albert C.",
""
]
] |
0707.1541 | Sarah McKagan | S. B. McKagan, K. K. Perkins, and C. E. Wieman | Why we should teach the Bohr model and how to teach it effectively | accepted by Physical Review Special Topics: Physics Education
Research; v2 includes more extensive analysis of data and responses to
reviewers | Physical Review Special Topics: PER 4, 010103 (2008) | 10.1103/PhysRevSTPER.4.010103 | null | physics.ed-ph | null | Some education researchers have claimed that we should not teach the Bohr
model of the atom because it inhibits students' ability to learn the true
quantum nature of electrons in atoms. Although the evidence for this claim is
weak, many have accepted it. This claim has implications for how to present
atoms in classes ranging from elementary school to graduate school. We present
results from a study designed to test this claim by developing a curriculum on
models of the atom, including the Bohr and Schrodinger models. We examine
student descriptions of atoms on final exams in transformed modern physics
classes using various versions of this curriculum. We find that if the
curriculum does not include sufficient connections between different models,
many students still have a Bohr-like view of atoms, rather than a more accurate
Schrodinger model. However, with an improved curriculum designed to develop
model-building skills and with better integration between different models, it
is possible to get most students to describe atoms using the Schrodinger model.
In comparing our results with previous research, we find that comparing and
contrasting different models is a key feature of a curriculum that helps
students move beyond the Bohr model and adopt Schrodinger's view of the atom.
We find that understanding the reasons for the development of models is much
more difficult for students than understanding the features of the models. We
also present interactive computer simulations designed to help students build
models of the atom more effectively.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 17:59:56 GMT"
},
{
"version": "v2",
"created": "Sat, 1 Mar 2008 21:36:46 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"McKagan",
"S. B.",
""
],
[
"Perkins",
"K. K.",
""
],
[
"Wieman",
"C. E.",
""
]
] |
0707.1542 | Tomasz Maszczyk | Tomasz Maszczyk | Noncommutative geometry through monoidal categories I | This paper has been withdrawn by the author, due a multiple
submission caused by a minor change in the title | null | null | null | math.AG math.KT | null | After introducing a noncommutative counterpart of commutative algebraic
geometry based on monoidal categories of quasi-coherent sheaves we show that
various constructions in noncommutative geometry (e.g. Morita equivalences,
Hopf-Galois extensions) can be given geometric meaning extending their
geometric interpretations in the commutative case. On the other hand, we show
that some constructions in commutative geometry (e.g. faithfully flat descent
theory, principal fibrations, equivariant and infinitesimal geometry) can be
interpreted as noncommutative geometric constructions applied to commutative
objects. For such generalized geometry we define global invariants constructing
cyclic objects from which we derive Hochschild, cyclic and periodic cyclic
homology (with coefficients) in the standard way.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:04:22 GMT"
},
{
"version": "v2",
"created": "Mon, 16 Jul 2007 11:18:26 GMT"
}
] | 2007-07-16T00:00:00 | [
[
"Maszczyk",
"Tomasz",
""
]
] |
0707.1543 | Daniel M. Kaplan | Daniel M. Kaplan | A New Experiment to Study Hyperon CP Violation and the Charmonium System | 16 pages, 3 figures, to appear in Proceedings of CTP symposium on
Supersymmetry at LHC: Theoretical and Experimental Perspectives, The British
University in Egypt, Cairo, Egypt, 11-14 March 2007 | Int.J.Mod.Phys.A22:5958-5972,2007 | 10.1142/S0217751X07039158 | null | hep-ex | null | Fermilab operates the world's most intense antiproton source, now exclusively
dedicated to serving the needs of the Tevatron Collider. The anticipated 2009
shutdown of the Tevatron presents the opportunity for a world-leading low- and
medium-energy antiproton program. We summarize the status of the Fermilab
antiproton facility and review physics topics for which a future experiment
could make the world's best measurements.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 01:57:45 GMT"
}
] | 2010-11-03T00:00:00 | [
[
"Kaplan",
"Daniel M.",
""
]
] |
0707.1544 | Stefano Scopel | Eung Jin Chun (Korea Inst. Advanced Study, Seoul & Michigan U., MCTP),
Stefano Scopel (Korea Inst. Advanced Study, Seoul) | Quintessential Kination and Leptogenesis | 13 pages, 8 figures | JCAP 0710:011,2007 | 10.1088/1475-7516/2007/10/011 | KIAS-P07031, MCTP-07-18 | astro-ph hep-ph | null | Thermal leptogenesis induced by the CP-violating decay of a right-handed
neutrino (RHN) is discussed in the background of quintessential kination, i.e.,
in a cosmological model where the energy density of the early Universe is
assumed to be dominated by the kinetic term of a quintessence field during some
epoch of its evolution. This assumption may lead to very different
observational consequences compared to the case of a standard cosmology where
the energy density of the Universe is dominated by radiation. We show that,
depending on the choice of the temperature T_r above which kination dominates
over radiation, any situation between the strong and the super--weak wash--out
regime are equally viable for leptogenesis, even with the RHN Yukawa coupling
fixed to provide the observed atmospheric neutrino mass scale ~ 0.05 eV. For M<
T_r < M/100, i.e., when kination stops to dominate at a time which is not much
later than when leptogenesis takes place, the efficiency of the process,
defined as the ratio between the produced lepton asymmetry and the amount of CP
violation in the RHN decay, can be larger than in the standard scenario of
radiation domination. This possibility is limited to the case when the neutrino
mass scale is larger than about 0.01 eV. The super--weak wash--out regime is
obtained for T_r << M/100, and includes the case when T_r is close to the
nucleosynthesis temperature ~ 1 MeV. Irrespective of T_r, we always find a
sufficient window above the electroweak temperature T ~ 100 GeV for the
sphaleron transition to thermalize, so that the lepton asymmetry can always be
converted to the observed baryon asymmetry.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 04:45:40 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Chun",
"Eung Jin",
"",
"Korea Inst. Advanced Study, Seoul & Michigan U., MCTP"
],
[
"Scopel",
"Stefano",
"",
"Korea Inst. Advanced Study, Seoul"
]
] |
0707.1545 | Ludmila Joukovskaya | Liudmila Joukovskaya | Dynamics in Nonlocal Cosmological Models Derived from String Field
Theory | 21 pages, 7 figures, v3: updated to match PRD version | Phys.Rev.D76:105007,2007 | 10.1103/PhysRevD.76.105007 | DAMTP-2007-67 | hep-th astro-ph gr-qc | null | A general class of nonlocal cosmological models is considered. A new method
for solving nonlocal Friedmann equations is proposed, and solutions of the
Friedmann equations with nonlocal operator are presented. The cosmological
properties of these solutions are discussed. Especially indicated is $p$-adic
cosmological model in which we have obtained nonsingular bouncing solution and
string field theory tachyon model in which we have obtained full solution of
nonlocal Friedmann equations with $w=-1$ at large times. The possibility of
obtaining realistic value of cosmological constant from nonlocal cosmological
models is also discussed.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 01:54:44 GMT"
},
{
"version": "v2",
"created": "Fri, 17 Aug 2007 22:57:46 GMT"
},
{
"version": "v3",
"created": "Thu, 29 Nov 2007 23:58:42 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Joukovskaya",
"Liudmila",
""
]
] |
0707.1546 | Daniel M. Kaplan | D. M. Kaplan, T. Hart, P. Allport | Producing an Intense, Cool Muon Beam via e+e- Annihilation | 7 pages, 2 figures, prepared for Proceedings of the NuFact06
Workshop, Irvine, CA, 23-30 August 2006 | null | null | null | physics.acc-ph | null | We consider a highly unconventional approach to generating muon and antimuon
bunches for a neutrino factory or muon collider: electron-positron annihilation
just above muon-antimuon threshold. This approach can produce low-emittance
bunches at high energy, easing the muon-cooling and acceleration challenges in
such facilities. However, the small (< 1 $\mu$b) useable production cross
section means that extraordinary beam-power and targeting challenges would have
to be met. We speculate on what this might entail.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 02:06:56 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Kaplan",
"D. M.",
""
],
[
"Hart",
"T.",
""
],
[
"Allport",
"P.",
""
]
] |
0707.1547 | Jules P. Halpern | J.P. Halpern, F. Camilo, E.V. Gotthelf | The Next Geminga: Search for Radio and X-ray Pulsations from the Neutron
Star Identified with 3EG J1835+5918 | 4 pages, 1 figure, to appear in The Astrophysical Journal | null | 10.1086/521355 | null | astro-ph | null | We report unsuccessful searches for pulsations from the neutron star RX
J1836.2+5925 identified with the EGRET source 3EG J1835+5918. A 24 hr
observation with the NRAO Green Bank Telescope at 820 MHz placed an upper limit
on flux density of 17 uJy for P > 10 ms, and gradually increasing limits for 1
< P < 10 ms. The equivalent luminosity is lower than that of any known pulsar
with the possible exception of the radio-quiet gamma-ray pulsar Geminga. A set
of observations with the Chandra X-ray Observatory HRC totaling 118 ks revealed
no pulsar with 1 ms < P < 10 s. The upper limit on its pulsed fraction is 35%
assuming a sinusoidal pulse shape. The position of RX J1836.2+5925 in Chandra
observations separated by 3 years is unchanged within errors, leading to an
upper limit on its proper motion of <0.14"/yr, or v < 530 km/s at d = 800 pc, a
maximum distance estimated from its thermal X-ray spectrum. With these null
results, the properties of 3EG J1835+5918 and its X-ray counterpart RX
J1836.2+5925 are consistent with a more distant or older version of Geminga, or
perhaps a recycled pulsar. Having nearly exhausted the capabilities of current
instrumentation at all wavelengths, it will likely fall to the Gamma-ray Large
Area Space Telescope to discover pulsations from 3EG J1835+5918.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 02:16:14 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Halpern",
"J. P.",
""
],
[
"Camilo",
"F.",
""
],
[
"Gotthelf",
"E. V.",
""
]
] |
0707.1548 | Kamel Aouiche | Kamel Aouiche and J\'er\^ome Darmont | Data Mining-based Materialized View and Index Selection in Data
Warehouses | null | null | null | null | cs.DB | null | Materialized views and indexes are physical structures for accelerating data
access that are casually used in data warehouses. However, these data
structures generate some maintenance overhead. They also share the same storage
space. Most existing studies about materialized view and index selection
consider these structures separately. In this paper, we adopt the opposite
stance and couple materialized view and index selection to take view-index
interactions into account and achieve efficient storage space sharing.
Candidate materialized views and indexes are selected through a data mining
process. We also exploit cost models that evaluate the respective benefit of
indexing and view materialization, and help select a relevant configuration of
indexes and materialized views among the candidates. Experimental results show
that our strategy performs better than an independent selection of materialized
views and indexes.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 02:45:10 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Aouiche",
"Kamel",
""
],
[
"Darmont",
"Jérôme",
""
]
] |
0707.1549 | James Storey | J.G. Storey, J.L. Tallon, G.V.M. Williams, J.W. Loram | Fermi arcs in cuprate superconductors: tracking the pseudogap below Tc
and above T* | 5 pages, 6 figures, accepted for publication as a Rapid Communication
in Physical Review B | null | 10.1103/PhysRevB.76.060502 | null | cond-mat.supr-con | null | Using an energy-momentum dispersion for Bi2Sr2CaCu2O8 obtained from
angle-resolved photoelectron spectroscopy we show that the shrinking Fermi arc
model of the pseudogap is inconsistent with Raman scattering below Tc and
specific heat near T*. By simulating the quasiparticle energy dispersion curves
we show that Fermi arcs are an artifact of a T-dependent scattering rate.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 02:55:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Storey",
"J. G.",
""
],
[
"Tallon",
"J. L.",
""
],
[
"Williams",
"G. V. M.",
""
],
[
"Loram",
"J. W.",
""
]
] |
0707.1550 | Shabnam Jabeen | S. Jabeen (for the D0 Collaboration) | Search for Single Top Quark Production Using Likelihood Discriminants at
D0 in Run II | 3 pages, 13 figures, to appear in proceeding of The Hadron Collider
Physics Symposium 2006, Durham, North Carolina, USA | null | null | null | hep-ex | null | We present an improved search for single top quarks in two production modes,
s-channel (tb) and t-channel (tqb). The search is performed in the
electron+jets and muon+jets decay channels, with one or more b-tagged jets, on
nearly 370 pb^{-1} of D0 Run II data collected between August 2002 and October
2004. Impact-parameter based b-quark tagging is used to select signal-like
events. We use a likelihood discriminant method to separate signals from
backgrounds. The resulting expected/observed 95% confidence level upper limits
on the single top quark production cross sections are 3.3/5.0pb (s-channel) and
4.3/4.4pb (t-channel).
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 03:33:11 GMT"
}
] | 2019-08-14T00:00:00 | [
[
"Jabeen",
"S.",
"",
"for the D0 Collaboration"
]
] |
0707.1551 | Edgardo Ugalde | Anne Cros, Antonio Morante, Edgardo Ugalde | Regulatory Dynamics on Random Networks: Asymptotic Periodicity and
Modularity | 23 pages, 3 figures | null | 10.1088/0951-7715/21/3/009 | null | math.DS | null | We study the dynamics of discrete-time regulatory networks on random
digraphs. For this we define ensembles of deterministic orbits of random
regulatory networks, and introduce some statistical indicators related to the
long-term dynamics of the system. We prove that, in a random regulatory
network, initial conditions converge almost surely to a periodic attractor. We
study the subnetworks, which we call modules, where the periodic asymptotic
oscillations are concentrated. We proof that those modules are dynamically
equivalent to independent regulatory networks.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 03:10:00 GMT"
},
{
"version": "v2",
"created": "Fri, 3 Aug 2007 23:08:47 GMT"
},
{
"version": "v3",
"created": "Fri, 1 Feb 2008 03:32:54 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cros",
"Anne",
""
],
[
"Morante",
"Antonio",
""
],
[
"Ugalde",
"Edgardo",
""
]
] |
0707.1552 | Michael Zieve | Robert M. Beals, Joseph L. Wetherell and Michael E. Zieve | Polynomials with a common composite | 20 pages; various minor changes, and some alternate proofs suggested
by the referee | Israel J. Math. 174 (2009) 93-117 | null | null | math.AG math.NT | null | Let f and g be nonconstant polynomials over an arbitrary field K. In this
paper we study the intersection of the polynomial rings K[f] and K[g], and in
particular we ask whether this intersection is larger than K. We completely
resolve this question when K has characteristic zero, and in positive
characteristic we present various results, examples, and algorithms.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:17:33 GMT"
},
{
"version": "v2",
"created": "Mon, 7 Apr 2008 21:41:38 GMT"
}
] | 2013-10-08T00:00:00 | [
[
"Beals",
"Robert M.",
""
],
[
"Wetherell",
"Joseph L.",
""
],
[
"Zieve",
"Michael E.",
""
]
] |
0707.1553 | Rajesh R. Parwani | Wei-Khim Ng and Rajesh R. Parwani | Nonlinear Dirac Equations | null | SIGMA 5 (2009), 023, 20 pages | 10.3842/SIGMA.2009.023 | null | hep-th quant-ph | http://creativecommons.org/licenses/by-nc-sa/3.0/ | We construct nonlinear extensions of Dirac's relativistic electron equation
that preserve its other desirable properties such as locality, separability,
conservation of probability and Poincar\'e invariance. We determine the
constraints that the nonlinear term must obey and classify the resultant
non-polynomial nonlinearities in a double expansion in the degree of
nonlinearity and number of derivatives. We give explicit examples of such
nonlinear equations, studying their discrete symmetries and other properties.
Motivated by some previously suggested applications we then consider nonlinear
terms that simultaneously violate Lorentz covariance and again study various
explicit examples. We contrast our equations and construction procedure with
others in the literature and also show that our equations are not gauge
equivalent to the linear Dirac equation. Finally we outline various physical
applications for these equations.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 03:40:40 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Feb 2009 06:01:21 GMT"
}
] | 2009-02-27T00:00:00 | [
[
"Ng",
"Wei-Khim",
""
],
[
"Parwani",
"Rajesh R.",
""
]
] |
0707.1554 | Philip Phillips | Ting-Pong Choy, Robert G. Leigh, Philip Phillips, and Philip D. Powell | Exact Integration of the High Energy Scale in Doped Mott Insulators | Published verison | Phys. Rev. B, vol. 77, 14512 (2008) | 10.1103/PhysRevB.77.014512 | null | cond-mat.str-el cond-mat.supr-con | null | We expand on our earlier work (cond-mat/0612130, Phys. Rev. Lett. {\bf 99},
46404 (2007)) in which we constructed the exact low-energy theory of a doped
Mott insulator by explicitly integrating (rather than projecting) out the
degrees of freedom far away from the chemical potential. The exact low-energy
theory contains degrees of freedom that cannot be obtained from projective
schemes. In particular a new charge $\pm 2e$ bosonic field emerges at low
energies that is not made out of elemental excitations. Such a field accounts
for dynamical spectral weight transfer across the Mott gap. At half-filling, we
show that two such excitations emerge which play a crucial role in preserving
the Luttinger surface along which the single-particle Green function vanishes.
In addition, the interactions with the bosonic fields defeat the artificial
local SU(2) symmetry that is present in the Heisenberg model. We also apply
this method to the Anderson-U impurity and show that in addition to the Kondo
interaction, bosonic degrees of freedom appear as well. Finally, we show that
as a result of the bosonic degree of freedom, the electron at low energies is
in a linear superposition of two excitations--one arising from the standard
projection into the low-energy sector and the other from the binding of a hole
and the boson.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 03:53:47 GMT"
},
{
"version": "v2",
"created": "Fri, 24 Aug 2007 05:42:16 GMT"
},
{
"version": "v3",
"created": "Thu, 6 Mar 2008 21:00:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Choy",
"Ting-Pong",
""
],
[
"Leigh",
"Robert G.",
""
],
[
"Phillips",
"Philip",
""
],
[
"Powell",
"Philip D.",
""
]
] |
0707.1555 | Dr. Alok Banerjee | K. Mukherjee and A. Banerjee | Changeover from Glassy ferromagnetism of the orbital domain state to
long range ferromagnetic ordering in La{_{0.9}}Sr_{0.1}MnO{_3} | null | Phys. Rev. B 77, 024430 (2008). | 10.1103/PhysRevB.77.024430 | null | cond-mat.str-el cond-mat.mtrl-sci | null | An attempt is made to resolve the controversy related to the low temperature
phase (ground state) of the low-doped ferromagnetic (FM)- insulator(I)
manganite through bulk magnetic measurements on La${_{0.9}}$Sr$_{0.1}$MnO${_3}$
sample. It is shown that the FM phase, formed out of well defined transition in
the low-doped system, becomes inhomogeneous with decrease in temperature. This
inhomogeniety is considered to be an outcome of the formation of orbital domain
state of e$_g$-electrons having hole rich (metallic) walls separating the hole
deficient (insulating) regions. The resulting complexity brings in
metastability and glassy behaviour within the FM phase at low temperature,
however, with no resemblance to spin glass, cluster glass or reentrant phases.
It shows ageing effect without memory but magnetic relaxation shows signatures
of inter-cluster interaction. The energy landscape picture of this glassy phase
is described in terms of hierarchical model. Further, it is shown that this
inhomogeneity disappear in La${_{0.9}}$Sr$_{0.1}$MnO$_{3.08}$ where, the
orbital domain state is destroyed by self doping resulting in reduction of
Mn$^{3+}$ and hence e$_g$-electrons. The ferromagnetic phase of the
non-stoichiometric sample, does not show glassy behaviour. It neither follows
'hierarchical model' nor 'droplet model' generally used to explain glassy or
inhomogeneous systems. Its magnetic response can be explained simply from the
domain wall dynamics of otherwise homogeneous ferromagnet.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 04:05:39 GMT"
}
] | 2008-02-15T00:00:00 | [
[
"Mukherjee",
"K.",
""
],
[
"Banerjee",
"A.",
""
]
] |
0707.1556 | Nicole F. Bell | Nicole F. Bell | How Magnetic is the Neutrino? | 9 pages, 6 figures. Talk given at Festschrift in honour of B. H. J
McKellar and G. C. Joshi | Int.J.Mod.Phys.A22:4891-4899,2007 | 10.1142/S0217751X07038256 | null | hep-ph | null | The existence of a neutrino magnetic moment implies contributions to the
neutrino mass via radiative corrections. We derive model-independent
"naturalness" upper bounds on the magnetic moments of Dirac and Majorana
neutrinos, generated by physics above the electroweak scale. For Dirac
neutrinos, the bound is several orders of magnitude more stringent than present
experimental limits. However, for Majorana neutrinos the magnetic moment bounds
are weaker than present experimental limits if $\mu_\nu$ is generated by new
physics at ~ 1 TeV, and surpass current experimental sensitivity only for new
physics scales > 10 -- 100 TeV. The discovery of a neutrino magnetic moment
near present limits would thus signify that neutrinos are Majorana particles.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 04:23:11 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bell",
"Nicole F.",
""
]
] |
0707.1557 | Ant\'igona Segura | A. Segura, V. S. Meadows, J. F. Kasting, D. Crisp and M. Cohen | Abiotic formation of O2 and O3 in high-CO2 terrestrial atmospheres | 27 pages, 15 figures, Astronomy & Astrophysics accepted | Astron.Astrophys.472:665-679,2007 | 10.1051/0004-6361:20066663 | null | astro-ph | null | Previous research has indicated that high amounts of ozone (O3) and oxygen
(O2) may be produced abiotically in atmospheres with high concentrations of
CO2. The abiotic production of these two gases, which are also characteristic
of photosynthetic life processes, could pose a potential "false-positive" for
remote-sensing detection of life on planets around other stars.We show here
that such false positives are unlikely on any planet that possesses abundant
liquid water, as rainout of oxidized species onto a reduced planetary surface
should ensure that atmospheric H2 concentrations remain relatively high, and
that O2 and O3 remain low. Our aim is to determine the amount of O3 and O2
formed in a high CO2 atmosphere for a habitable planet without life. We use a
photochemical model that considers hydrogen (H2) escape and a detailed hydrogen
balance to calculate the O2 and O3 formed on planets with 0.2 of CO2 around the
Sun, and 0.02, 0.2 and 2 bars of CO2 around a young Sun-like star with higher
UV radiation. The concentrations obtained by the photochemical model were used
as input in a radiative transfer model that calculated the spectra of the
modeled planets. The O3 and O2 concentrations in the simulated planets are
extremely small, and unlikely to produce a detectable signature in the spectra
of those planets. We conclude that with a balanced hydrogen budget, and for
planets with an active hydrological cycle, abiotic formation of O2 and O3 is
unlikely to create a possible false positive for life detection in either the
visible/near-infrared or mid-infrared wavelength regimes.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 05:07:10 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Segura",
"A.",
""
],
[
"Meadows",
"V. S.",
""
],
[
"Kasting",
"J. F.",
""
],
[
"Crisp",
"D.",
""
],
[
"Cohen",
"M.",
""
]
] |
0707.1558 | Eric Sanchis | Eric Sanchis (LGC) | Autonomy with regard to an Attribute | null | null | null | null | cs.MA | null | This paper presents a model of autonomy called autonomy with regard to an
attribute applicable to cognitive and not cognitive artificial agents. Three
criteria (global / partial, social / nonsocial, absolute / relative) are
defined and used to describe the main characteristics of this type of autonomy.
A software agent autonomous with regard to the mobility illustrates a possible
implementation of this model.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 05:05:57 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Sanchis",
"Eric",
"",
"LGC"
]
] |
0707.1559 | Rachid Touzani | Gunther H. Peichl, Rachid Touzani | An accurate finite element method for elliptic interface problems | null | null | null | null | math.NA | null | A finite element method for elliptic problems with discontinuous coefficients
is presented. The discontinuity is assumed to take place along a closed smooth
curve. The proposed method allows to deal with meshes that are not adapted to
the discontinuity line. The (nonconforming) finite element space is enriched
with local basis functions. We prove an optimal convergence rate in the
$H^1$--norm. Numerical tests confirm the theoretical results.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 05:07:27 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Peichl",
"Gunther H.",
""
],
[
"Touzani",
"Rachid",
""
]
] |
0707.1560 | Jan Jurcak | Jan Jur\v{c}\'ak, Luis Bellot Rubio, Kiyoshi Ichimoto, Yukio
Katsukawa, Bruce Lites, Shin'ichi Nagata, Toshifumi Shimizu, Yoshinori
Suematsu, Theodore Tarbell, Alan Title, Saku Tsuneta | The Analysis of Penumbral Fine Structure Using an Advanced Inversion
Technique | 7 pages, 6 figures, submitted to PASJ | null | 10.1093/pasj/59.sp3.S601 | null | astro-ph | null | We present a method to study the penumbral fine structure using data obtained
by the spectropolarimeter onboard HINODE. For the first time, the penumbral
filaments can be considered as resolved in spectropolarimetric measurements.
This enables us to use inversion codes with only one-component model
atmospheres, and thus assign the obtained stratifications of plasma parameters
directly to the penumbral fine structure. This approach is applied to the
limb-side part of the penumbra in active region NOAA 10923. The preliminary
results show a clear dependence of the plasma parameters on continuum intensity
in the inner penumbra, i.e. weaker and horizontal magnetic field along with
increased line-of-sight velocity are found in the low layers of the bright
filaments. The results in the mid penumbra are ambiguous and future analyses
are necessary to unveil the magnetic field structure and other plasma
parameters there.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 05:10:57 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Jurčák",
"Jan",
""
],
[
"Rubio",
"Luis Bellot",
""
],
[
"Ichimoto",
"Kiyoshi",
""
],
[
"Katsukawa",
"Yukio",
""
],
[
"Lites",
"Bruce",
""
],
[
"Nagata",
"Shin'ichi",
""
],
[
"Shimizu",
"Toshifumi",
""
],
[
"Suematsu",
"Yoshinori",
""
],
[
"Tarbell",
"Theodore",
""
],
[
"Title",
"Alan",
""
],
[
"Tsuneta",
"Saku",
""
]
] |
0707.1561 | Kazuaki Ota | Kazuaki Ota, Masanori Iye, Nobunari Kashikawa, Kazuhiro Shimasaku,
Masakazu A.R. Kobayashi, Tomonori Totani, Masahiro Nagashima, Tomoki
Morokuma, Hisanori Furusawa, Takashi Hattori, Yuichi Matsuda, Tetsuya
Hashimoto, Masami Ouchi | The Reionization and Galaxy Evolution Probed by z=7 Lyman Alpha Emitters | published in Astrophysical Journal | The Astrophysical Journal, Volume 677, Issue 1, pp. 12-26 (2008) | 10.1086/529006 | null | astro-ph | null | We made a narrowband NB973 (bandwidth of 200A at 9755A) imaging of the Subaru
Deep Field (SDF) and found two z=7 Lyman alpha emitter (LAE) candidates down to
NB973=24.9. Carrying out deep follow-up spectroscopy, we identified one of them
as a real z=6.96 LAE. This has shown that galaxy formation was in progress just
750 Myr after the Big Bang. Meanwhile, the Lyman alpha line luminosity function
of LAE is known to decline from z=5.7 to 6.6 in the SDF. L* at z=6.6 is 40-60%
of that at z=5.7. We also confirm that the number density of z=7 LAE is only
17% of the density at z=6.6 comparing the latest SDF LAE samples. This series
of significant decreases in LAE density with increasing redshift can be the
result of galaxy evolution during these epochs. However, using the UV continuum
luminosity functions of LAEs, those of Lyman break galaxies, and a LAE
evolution model based on the hierarchical clustering, we find that galaxy
evolution alone cannot explain all the decrease in density. This extra density
deficit can be interpreted as the attenuation of the Lyman alpha photons from
LAEs due to a rapid evolution of neutral hydrogen fraction during the ongoing
cosmic reionization at z~6.6-7.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 07:02:44 GMT"
},
{
"version": "v2",
"created": "Tue, 22 Apr 2008 07:14:27 GMT"
}
] | 2012-07-25T00:00:00 | [
[
"Ota",
"Kazuaki",
""
],
[
"Iye",
"Masanori",
""
],
[
"Kashikawa",
"Nobunari",
""
],
[
"Shimasaku",
"Kazuhiro",
""
],
[
"Kobayashi",
"Masakazu A. R.",
""
],
[
"Totani",
"Tomonori",
""
],
[
"Nagashima",
"Masahiro",
""
],
[
"Morokuma",
"Tomoki",
""
],
[
"Furusawa",
"Hisanori",
""
],
[
"Hattori",
"Takashi",
""
],
[
"Matsuda",
"Yuichi",
""
],
[
"Hashimoto",
"Tetsuya",
""
],
[
"Ouchi",
"Masami",
""
]
] |
0707.1562 | Mais Suleymanov | M.K. Suleymanov, E. U. Khan, K. Ahmed, Mahnaz Q. Haseeb, Farida Tahir
and Y. H. Huseynaliyev | Percolation cluster formation at ultrarelativistic heavy ion collisions | 2 pages | Acta Phys.Polon.Supp.1:405-406,2008 | null | null | nucl-ex | null | We expect that the experimental study of percolation cluster formation and
appearance of the critical transparency of the strongly interacting matter can
give the information about the onset state of deconfinement.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 05:35:17 GMT"
}
] | 2009-06-12T00:00:00 | [
[
"Suleymanov",
"M. K.",
""
],
[
"Khan",
"E. U.",
""
],
[
"Ahmed",
"K.",
""
],
[
"Haseeb",
"Mahnaz Q.",
""
],
[
"Tahir",
"Farida",
""
],
[
"Huseynaliyev",
"Y. H.",
""
]
] |
0707.1563 | Ashoke Sen | Ashoke Sen | Rare Decay Modes of Quarter BPS Dyons | LaTeX file, 9 pages; v2: a minor logical error corrected with no
change in the results | JHEP 0710:059,2007 | 10.1088/1126-6708/2007/10/059 | null | hep-th | null | The degeneracy of quarter BPS dyons in N=4 supersymmetric string theories is
known to jump across walls of marginal stability on which a quarter BPS dyon
can decay into a pair of half BPS dyons. We show that as long as the electric
and magnetic charges of the original dyon are primitive elements of the charge
lattice, the subspaces of the moduli space on which a quarter BPS dyon becomes
marginally unstable against decay into a pair of quarter BPS dyons or a half
BPS dyon and a quarter BPS dyon are of codimension two or more. As a result any
pair of generic points in the moduli space can be connected by a path avoiding
these subspaces and there is no jump in the spectrum associated with these
subspaces.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 06:21:42 GMT"
},
{
"version": "v2",
"created": "Thu, 12 Jul 2007 16:00:34 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Sen",
"Ashoke",
""
]
] |
0707.1564 | Soon Jae Moon | S.J. Moon, W.S. Choi, S.J. Kim, Y.S. Lee, P.G. Khalifah, D. Mandrus,
and T.W. Noh | Orbital-Driven Electronic Structure Changes and the Resulting Optical
Anisotropy of the Quasi-Two-Dimensional Spin Gap Compound La4Ru2O10 | null | null | 10.1103/PhysRevLett.100.116404 | null | cond-mat.str-el | null | We investigated the electronic response of the quasi-two-dimensional spin gap
compound La4Ru2O10 using optical spectroscopy. We observed drastic changes in
the optical spectra as the temperature decreased, resulting in anisotropy in
the electronic structure of the spin-singlet ground state. Using the
orbital-dependent hopping analysis, we found that orbital ordering plays a
crucial role in forming the spin gap state in the non-one-dimensional material.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 05:57:55 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Moon",
"S. J.",
""
],
[
"Choi",
"W. S.",
""
],
[
"Kim",
"S. J.",
""
],
[
"Lee",
"Y. S.",
""
],
[
"Khalifah",
"P. G.",
""
],
[
"Mandrus",
"D.",
""
],
[
"Noh",
"T. W.",
""
]
] |
0707.1565 | Nicolas Treps | Tania Golubeva (V.A. Fock Physics Institute), Yuri Golubev (V.A. Fock
Physics Institute), Claude Fabre (LKB - Jussieu), Nicolas Treps (LKB -
Jussieu) | Quantum state of an injected TROPO above threshold : purity, Glauber
function and photon number distribution | null | null | 10.1140/epjd/e2007-00290-6 | null | quant-ph | null | In this paper we investigate several properties of the full signal-idler-pump
mode quantum state generated by a triply resonant non-degenerate Optical
Parametric Oscillator operating above threshold, with an injected wave on the
signal and idler modes in order to lock the phase diffusion process. We
determine and discuss the spectral purity of this state, which turns out not to
be always equal to 1 even though the three interacting modes have been taken
into account at the quantum level. We have seen that the purity is essentially
dependent on the weak intensity of the injected light and on an asymmetry of
the synchronization. We then derive the expression of its total three-mode
Glauber P-function, and calculate the joint signal-idler photon number
probability distribution and investigate their dependence on the injection.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 06:31:32 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Golubeva",
"Tania",
"",
"V.A. Fock Physics Institute"
],
[
"Golubev",
"Yuri",
"",
"V.A. Fock\n Physics Institute"
],
[
"Fabre",
"Claude",
"",
"LKB - Jussieu"
],
[
"Treps",
"Nicolas",
"",
"LKB -\n Jussieu"
]
] |
0707.1566 | Parameswaran Sankaran | Parameswaran Sankaran | K theory of smooth complete toric varieties and related spaces | 11 pages, no figures | null | null | null | math.AT math.AG | null | The K-rings of non-singular complex pro jective varieties as well as quasi-
toric manifolds were described in terms of generators and relations in an
earlier work of the author with V. Uma. In this paper we obtain a similar
description for complete non-singular toric varieties. Indeed, our approach
enables us to obtain such a description for the more general class of torus
manifolds with locally standard torus action and orbit space a homology
polytope.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 06:35:00 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Sankaran",
"Parameswaran",
""
]
] |
0707.1567 | Julia Unterhinninghofen | J. Unterhinninghofen, D. Manske, and A. Knorr | Theory for ultrafast nonequilibrium dynamics in d-wave superconductors | 4 pages, 4 figures | null | 10.1103/PhysRevB.77.180509 | null | cond-mat.supr-con cond-mat.str-el | null | We use density-matrix theory to calculate the ultrafast dynamics of
unconventional superconductors from a microscopic viewpoint. We calculate the
time evolution of the optical conductivity as well as pump-probe spectra for a
d-wave order parameter. Three regimes can be distinguished in the spectra. The
Drude response at low photon energies is the only one of those which has been
measured experimentally so far. At higher energies, we predict two more
regimes: the pair-breaking peak, which is reduced as Cooper-pairs are broken up
by the exciting pulse; and a suppression above the pair-breaking peak due to
nonequilibrium quasiparticles. Furthermore, we consider the influence of the
electron-phonon coupling, and derive rate equations which have been widely used
so far.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 06:55:19 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Unterhinninghofen",
"J.",
""
],
[
"Manske",
"D.",
""
],
[
"Knorr",
"A.",
""
]
] |
0707.1568 | Michele Correggi | M. Correggi, T. Rindler-Daller, J. Yngvason | Rapidly Rotating Bose-Einstein Condensates in Homogeneous Traps | LaTex2e, 16 pages | J. Math. Phys. 48, 102103 (2007) | 10.1063/1.2789557 | null | math-ph cond-mat.other cond-mat.stat-mech math.MP | null | We extend the results of a previous paper on the Gross-Pitaevskii description
of rotating Bose-Einstein condensates in two-dimensional traps to confining
potentials of the form V(r) = r^s, $2<s <\infty$. Writing the coupling constant
as $1/\epsilon^2$ we study the limit $\epsilon \to 0$. We derive rigorously the
leading asymptotics of the ground state energy and the density profile when the
rotation velocity \Omega tends to infinity as a power of $1/\epsilon$. The case
of asymptotically homogeneous potentials is also discussed.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 06:56:32 GMT"
}
] | 2007-10-11T00:00:00 | [
[
"Correggi",
"M.",
""
],
[
"Rindler-Daller",
"T.",
""
],
[
"Yngvason",
"J.",
""
]
] |
0707.1569 | Subhadip Raychaudhuri | S. Raychaudhuri, E. Willgohs, T. Nguyen, E. M. Khan, T. Goldkorn | Cell-to-Cell stochastic fluctuations in apoptotic signaling can decide
between life and death | 6 pages, 3 figures | Biophysical Journal, 95:3559-3562 (2008) | 10.1529/biohysj.108.135483 | null | q-bio.MN physics.bio-ph physics.med-ph | null | Apoptosis, or genetically programmed cell death, is a crucial cellular
process that maintains the balance between life and death in cells. The precise
molecular mechanism of apoptosis signaling and how these two pathways are
differentially activated under distinct apoptotic stimuli is poorly understood.
We developed a Monte Carlo-based stochastic simulation model that can
characterize distinct signaling behaviors in the two major pathways of
apoptotic signaling using a novel probability distribution-based approach.
Specifically, we show that for a weak death signal, such as low levels of death
ligand Fas (CD95) binding or under stress conditions, the type 2 mitochondrial
pathway dominates apoptotic signaling. Our results also show signaling in the
type 2 pathway is stochastic, where the population average over many cells does
not capture the cell-to-cell fluctuations in the time course (~1 - 10 hours) of
downstream caspase-3 activation. On the contrary, the probability distribution
of caspase-3 activation for the mitochondrial pathway shows a distinct bimodal
behavior that can be used to characterize the stochastic signaling in type 2
apoptosis. Interestingly, such stochastic fluctuations in apoptosis signaling
happen even in the presence of large numbers of signaling molecules. In a
fluctuating environment, such stochasticity in the timecourse of caspase-3
activation may be an adaptive mechanism for allowing a competing survival
signal to win over a weak death trigger before the critical cell fate decision
is made and thus minimizes the risk of pathologies.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 19:40:51 GMT"
}
] | 2009-02-06T00:00:00 | [
[
"Raychaudhuri",
"S.",
""
],
[
"Willgohs",
"E.",
""
],
[
"Nguyen",
"T.",
""
],
[
"Khan",
"E. M.",
""
],
[
"Goldkorn",
"T.",
""
]
] |
0707.1570 | David Alonso-Gutierrez | David Alonso-Gutierrez | About the isotropy constant of random convex sets | 8 pages | null | null | null | math.MG math.FA | null | Let K be the symmetric convex hull of m independent random vectors uniformly
distributed on the unit sphere of R^n. We prove that, for every $\delta>0$, the
isotropy constant of K is bounded by a constant $c(\delta)$ with high
probability, provided that $m\geq (1+\delta)n$.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 07:09:16 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Alonso-Gutierrez",
"David",
""
]
] |
0707.1571 | Chandru Iyer | Chandru Iyer | Observations on the motion of a Tachyon | Two Pages, Two references | null | null | null | physics.gen-ph | null | Some aspects of the motion of a tachyon is discussed. It is shown that the
inertial frame Sigma-Prime around which the tachyon switches the direction of
its motion, does not observe any movement of the tachyon at all. Inertial
frames on either side of Sigma-Prime observe the tachyon to be moving at very
large speeds but in opposite direction. Sigma-Prime itself observes only a
sudden appearance and immediate disappearance of a long rod like object. Thus
unbounded speeds in either direction give the same result in the limit. This
suggests that negative numbers as a physical quantity are not meaningful.
Subtraction can be used integral to a formula but the final result has to be
interpreted with a positive answer. This means the abstract quantity -infinity
indicating an unbounded negative number is not meaningful. The situation is
also compared with Tan (Pi/2)+ and Tan(Pi/2)-. The conclusion is that in the
limit, travel at unbounded speed is direction independent and gives the
connotation of many identities to the same particle.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 19:16:23 GMT"
},
{
"version": "v2",
"created": "Fri, 13 Jul 2007 07:12:07 GMT"
}
] | 2011-11-10T00:00:00 | [
[
"Iyer",
"Chandru",
""
]
] |
0707.1572 | Navin Khaneja | Navin Khaneja | Switched Control of Electron Nuclear Spin Systems | null | null | 10.1103/PhysRevA.76.032326 | null | quant-ph | null | In this article, we study control of electron-nuclear spin dynamics at
magnetic field strengths where the Larmor frequency of the nucleus is
comparable to the hyperfine coupling strength. The quantization axis for the
nuclear spin differs from the static B_0 field direction and depends on the
state of the electron spin. The quantization axis can be switched by flipping
the state of electron spin, allowing for universal control on nuclear spin
states. We show that by performing a sequence of flips (each followed by a
suitable delay), we can perform any desired rotation on the nuclear spins,
which can also be conditioned on the state of the electron spin. These
operations, combined with electron spin rotations can be used to synthesize any
unitary transformation on the coupled electron-nuclear spin system. We discuss
how these methods can be used for design of experiments for transfer of
polarization from the electron to the nuclear spins.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 07:58:44 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Khaneja",
"Navin",
""
]
] |
0707.1573 | Wolfgang Kapferer | W. Kapferer (1), T. Kronberger (1), J. Weratschnig (1), and S.
Schindler (1) ((1) Institut fuer Astro- und Teilchenphysik, Universitaet
Innsbruck) | X-ray measured metallicities of the intra-cluster medium: a good measure
for the metal mass? | 7 pages, 9 figures, accepted for publication in A&A | null | 10.1051/0004-6361:20077563 | null | astro-ph | null | Aims. We investigate whether X-ray observations map heavy elements in the
Intra-Cluster Medium (ICM) well and whether the X-ray observations yield good
estimates for the metal mass, with respect to predictions on transport mech-
anisms of heavy elements from galaxies into the ICM. We further test the
accuracy of simulated metallicity maps. Methods. We extract synthetic X-ray
spectra from N-body/hydrodynamic simulations including metal enrichment pro-
cesses, which we then analyse with the same methods as are applied to
observations. By changing the metal distribution in the simulated galaxy
clusters, we investigate the dependence of the overall metallicity as a
function of the metal distribution. In addition we investigate the difference
of X-ray weighted metal maps produced by simulations and metal maps extracted
from artifcial X-ray spectra, which we calculate with SPEX2.0 and analyse with
XSPEC12.0. Results. The overall metallicity depends strongly on the
distribution of metals within the galaxy cluster. The more inhomogeneously the
metals are distributed within the cluster, the less accurate is the metallicity
as a measure for the true metal mass. The true metal mass is generally
underestimated by X-ray observations. The difference between the X-ray weighted
metal maps and the metal maps from synthetic X-ray spectra is on average less
than 7% in the temperature regime above T > 3E7 K, i.e. X-ray weighted metal
maps can be well used for comparison with observed metal maps. Extracting the
metal mass in the central parts (r < 500 kpc) of galaxy clusters with X-ray
observations results in metal mass underestimates up to a factor of three.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:08:44 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kapferer",
"W.",
""
],
[
"Kronberger",
"T.",
""
],
[
"Weratschnig",
"J.",
""
],
[
"Schindler",
"S.",
""
]
] |
0707.1574 | Matteo Beccaria | Matteo Beccaria | Three loop anomalous dimensions of twist-3 gauge operators in N=4 SYM | 20 pages, JHEP style | JHEP 0709:023,2007 | 10.1088/1126-6708/2007/09/023 | null | hep-th | null | We propose a closed expression for the three loop anomalous dimension of a
class of twist-3 operators built with gauge fields and covariant derivatives.
To this aim, we solve the long-range Bethe Ansatz equations at finite spin and
provide a consistent analytical formula obtained assuming maximal
transcendentality violation as suggested by the known one-loop anomalous
dimension. The final result reproduces the universal cusp anomalous dimension
and obeys recursion relations inspired by the principle of reciprocity
invariance.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:12:17 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Beccaria",
"Matteo",
""
]
] |
0707.1575 | Lech Jakobczyk | L. Derkacz, L. Jakobczyk | Entanglement of a class of mixed two - qutrit states | 4 pages, 4 figures | null | 10.1103/PhysRevA.76.042304 | null | quant-ph | null | We compute the measure of entanglement for some classes of states belonging
to the simplex of Bell - diagonal states of two qutrits.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:15:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Derkacz",
"L.",
""
],
[
"Jakobczyk",
"L.",
""
]
] |
0707.1576 | Osman Teoman Turgut | Burak Tevfik Kaynak, O. Teoman Turgut | Symbol calculus and zeta--function regularized determinants | Added references, some typos corrected, published version | J.Math.Phys.48:113501,2007 | 10.1063/1.2801883 | null | math-ph math.MP | null | In this work, we use semigroup integral to evaluate zeta-function regularized
determinants. This is especially powerful for non--positive operators such as
the Dirac operator. In order to understand fully the quantum effective action
one should know not only the potential term but also the leading kinetic term.
In this purpose we use the Weyl type of symbol calculus to evaluate the
determinant as a derivative expansion. The technique is applied both to a
spin--0 bosonic operator and to the Dirac operator coupled to a scalar field.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:20:18 GMT"
},
{
"version": "v2",
"created": "Fri, 7 Dec 2007 09:11:09 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kaynak",
"Burak Tevfik",
""
],
[
"Turgut",
"O. Teoman",
""
]
] |
0707.1577 | Deryk Osthus | Daniela K\"uhn, Deryk Osthus and Andrew Young | k-Ordered Hamilton cycles in digraphs | null | null | null | null | math.CO | null | Given a digraph D, the minimum semi-degree of D is the minimum of its minimum
indegree and its minimum outdegree. D is k-ordered Hamiltonian if for every
ordered sequence of k distinct vertices there is a directed Hamilton cycle
which encounters these vertices in this order. Our main result is that every
digraph D of sufficiently large order n with minimum semi-degree at least
(n+k)/2 -1 is k-ordered Hamiltonian. The bound on the minimum semi-degree is
best possible. An undirected version of this result was proved earlier by
Kierstead, S\'ark\"ozy and Selkow.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:35:24 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Kühn",
"Daniela",
""
],
[
"Osthus",
"Deryk",
""
],
[
"Young",
"Andrew",
""
]
] |
0707.1578 | Heng Fan | Heng Fan, Yong-Cheng Ou, and Vwani Roychowdhury | Entangled multi-qubit states without higher-tangle | 4 pages, 1 figure | null | null | null | quant-ph | null | We analyze mixed multi-qubit states composed of a W class state and a product
state with all qubit in |0>. We find the optimal pure state decomposition and
convex roofs for higher-tangle with bipartite partition between one qubit and
the rest qubits for those mixed states. The optimality of the decomposition is
ensured by the Coffman-Kundu-Wootters (CKW) inequality which describes the
monogamy of quantum entanglement. The generalized monogamy inequality is found
to be true for W class states with arbitrary partitions between one qubit and
multi-qubit.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:48:20 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Fan",
"Heng",
""
],
[
"Ou",
"Yong-Cheng",
""
],
[
"Roychowdhury",
"Vwani",
""
]
] |
0707.1579 | Yurie Okabe | Yurie Okabe and Masaki Sasai | Stable stochastic dynamics in yeast cell cycle | main text, 2 supporting texts, 3 supplementary tables | null | 10.1529/biophysj.107.109991 | null | q-bio.MN | null | Chemical reactions in cell are subject to intense stochastic fluctuations. An
important question is how the fundamental physiological behavior of cell is
kept stable against those noisy perturbations. In this paper a stochastic model
of cell cycle of budding yeast is constructed to analyze the effects of noise
on the cell cycle oscillation. The model predicts intense noise in levels of
mRNAs and proteins, and the simulated protein levels explain the observed
statistical tendency of noise in populations of synchronous and asynchronous
cells. In spite of intense noise in levels of proteins and mRNAs, cell cycle is
stable enough to bring the largely perturbed cells back to the physiological
cyclic oscillation. The model shows that consecutively appearing fixed points
are the origin of this stability of cell cycle.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:50:50 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Okabe",
"Yurie",
""
],
[
"Sasai",
"Masaki",
""
]
] |
0707.1580 | Stafford Withington Prof. | S. Withington, G. Saklatvala and M. P. Hobson | Theoretical Analysis of Astronomical Phased Arrays | null | null | null | null | astro-ph | null | Low-noise phased arrays are essential for the next generation of microwave
and submillimetre wave astronomy. We analyze their behaviour from a functional
perspective, and show that their operation is intimately related to the
mathematical theory of frames. No assumptions are made about the orthogonality
or linear independence of the synthesised beams. Frame theory allows an
unambiguous assessment of whether the outputs of an array can be used to
observe a field or brightness distribution within a given class. Image
reconstruction is carried out using dual beams. We identify the natural modes
of phased arrays, and carry out an analysis of noise. The scheme allows the
expectation values, the mean-square fluctuations, and the correlations between
fluctuations at the output ports of a phased array to be determined for a
source in any state of spatial coherence. Both classical and photon-counting
statistics are included. Our model is conceptually powerful, and suggests many
simulation and image recovery techniques.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:02:37 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Withington",
"S.",
""
],
[
"Saklatvala",
"G.",
""
],
[
"Hobson",
"M. P.",
""
]
] |
0707.1581 | Tony Ladd | Burkhard Duenweg, Ulf D. Schiller and Anthony J. C. Ladd | Statistical Mechanics of the Fluctuating Lattice Boltzmann Equation | Submitted to Physical Review E-11 pages Corrected Author(s) field on
submittal form | null | 10.1103/PhysRevE.76.036704 | null | cond-mat.soft | null | We propose a new formulation of the fluctuating lattice Boltzmann equation
that is consistent with both equilibrium statististical mechanics and
fluctuating hydrodynamics. The formalism is based on a generalized lattice-gas
model, with each velocity direction occupied by many particles. We show that
the most probable state of this model corresponds to the usual equilibrium
distribution of the lattice Boltzmann equation. Thermal fluctuations about this
equilibrium are controlled by the mean number of particles at a lattice site.
Stochastic collision rules are described by a Monte Carlo process satisfying
detailed balance. This allows for a straightforward derivation of discrete
Langevin equations for the fluctuating modes. It is shown that all
non-conserved modes should be thermalized, as first pointed out by Adhikari et
al.; any other choice violates the condition of detailed balance. A
Chapman-Enskog analysis is used to derive the equations of fluctuating
hydrodynamics on large length and time scales; the level of fluctuations is
shown to be thermodynamically consistent with the equation of state of an
isothermal, ideal gas. We believe this formalism will be useful in developing
new algorithms for thermal and multiphase flows.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:09:05 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Duenweg",
"Burkhard",
""
],
[
"Schiller",
"Ulf D.",
""
],
[
"Ladd",
"Anthony J. C.",
""
]
] |
0707.1582 | Politi Paolo | Alessandro Vindigni, Niculin Saratz, Oliver Portmann, Danilo Pescia,
Paolo Politi | Stripe width and non-local domain walls in the two-dimensional Dipolar
Frustrated Ising Ferromagnet | 5 pages, the manuscript has been rewritten in several parts and
figures have been modified. To be published in Physical Review B | Phys. Rev. B 77, 092414 (2008) | 10.1103/PhysRevB.77.092414 | null | cond-mat.stat-mech cond-mat.mtrl-sci | null | We describe a novel type of magnetic domain wall which, in contrast to Bloch
or Neel walls, is non-localized and, in a certain temperature range,
non-monotonic. The wall appears as the mean-field solution of the
two-dimensional ferromagnetic Ising model frustrated by the long-ranged dipolar
interaction. We provide experimental evidence of this wall delocalization in
the stripe-domain phase of perpendicularly magnetized ultrathin magnetic films.
In agreement with experimental results, we find that the stripe width decreases
with increasing temperature and approaches a finite value at the
Curie-temperature following a power law. The same kind of wall and a similar
temperature dependence of the stripe width is expected in the mean-field
approximation of the two-dimensional Coulomb frustrated Ising ferromagnet.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:20:19 GMT"
},
{
"version": "v2",
"created": "Fri, 29 Feb 2008 13:01:40 GMT"
}
] | 2008-03-31T00:00:00 | [
[
"Vindigni",
"Alessandro",
""
],
[
"Saratz",
"Niculin",
""
],
[
"Portmann",
"Oliver",
""
],
[
"Pescia",
"Danilo",
""
],
[
"Politi",
"Paolo",
""
]
] |
0707.1583 | Carlo Pierleoni | Carlo Pierleoni (1), Barbara Capone (2), Jean-Pierre Hansen (2) ((1)
INFM CRS-SOFT and Physics Dept. University of L'Aquila, Italy, (2) University
Chemical Laboratory, Cambridge, United Kingdom) | A multi-blob representation of semi-dilute polymer solutions | 4 pages, 4 figures | null | 10.1063/1.2803421 | null | cond-mat.soft cond-mat.stat-mech | null | A coarse-grained multi-blob description of polymer solutions is presented,
based on soft, transferable effective interactions between bonded and
non-bonded blobs. The number of blobs is chosen such that the blob density does
not exceed their overlap threshold, allowing polymer concentrations to be
explored deep into the semi-dilute regime. This quantitative multi-blob
description is shown to preserve known scaling laws of polymer solutions and
provides accurate estimates of amplitudes, while leading to orders of magnitude
increase of simulation efficiency and allowing analytic calculations of
structural and thermodynamic properties.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:34:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Pierleoni",
"Carlo",
""
],
[
"Capone",
"Barbara",
""
],
[
"Hansen",
"Jean-Pierre",
""
]
] |
0707.1584 | Vladimir Tarasov | V. E. Tarasov, V. V. Khabarov, A. E. Kudryavtsev, V. M. Weinberg | On the K^+D Interaction at Low Energies | 22 pages, 5 figures | Phys.Atom.Nucl.71:1410-1423,2008 | 10.1134/S1063778808080127 | null | nucl-th | null | The Kd reactions are considered in the impulse approximation with NN
final-state interactions (NN FSI) taken into account. The realistic parameters
for the KN phase shifts are used. The "quasi-elastic" energy region, in which
the elementary KN interaction is predominantly elastic, is considered. The
theoretical predictions are compared with the data on the K^+d->K^+pn,
K^+d->K^0pp, K^+d->K^+d and K^+d total cross sections. The NN FSI effect in the
reaction K^+d->K^+pn has been found to be large. The predictions for the Kd
cross sections are also given for slow kaons, produced from phi(1020) decays,
as the functions of the isoscalar KN scattering length a_0. These predictions
can be used to extract the value of a_0 from the data.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:59:32 GMT"
},
{
"version": "v2",
"created": "Wed, 28 Nov 2007 18:47:23 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Tarasov",
"V. E.",
""
],
[
"Khabarov",
"V. V.",
""
],
[
"Kudryavtsev",
"A. E.",
""
],
[
"Weinberg",
"V. M.",
""
]
] |
0707.1585 | Peter Schattschneider | L. Calmels, F. Houdellier, B. Warot-Fonrose, C. Gatel, M.J. H\"ytch,
V. Serin, E. Snoeck, P. Schattschneider | Experimental application of sum rules for electron energy loss magnetic
chiral dichroism | 11 pages, 2 figures | null | 10.1103/PhysRevB.76.060409 | null | cond-mat.other | null | We present a derivation of the orbital and spin sum rules for magnetic
circular dichroic spectra measured by electron energy loss spectroscopy in a
transmission electron microscope. These sum rules are obtained from the
differential cross section calculated for symmetric positions in the
diffraction pattern. Orbital and spin magnetic moments are expressed explicitly
in terms of experimental spectra and dynamical diffraction coefficients. We
estimate the ratio of spin to orbital magnetic moments and discuss first
experimental results for the Fe L_{2,3} edge.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 10:20:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Calmels",
"L.",
""
],
[
"Houdellier",
"F.",
""
],
[
"Warot-Fonrose",
"B.",
""
],
[
"Gatel",
"C.",
""
],
[
"Hÿtch",
"M. J.",
""
],
[
"Serin",
"V.",
""
],
[
"Snoeck",
"E.",
""
],
[
"Schattschneider",
"P.",
""
]
] |
0707.1586 | Ali Murat Guler | The CHORUS Collaboration | Charged-Particle Multiplicities in Charged-Current Neutrino-- and
Anti-Neutrino--Nucleus Interactions | 17 pages, 5 figures | Eur.Phys.J.C51:775-785,2007 | 10.1140/epjc/s10052-007-0366-8 | null | hep-ex | null | The CHORUS experiment, designed to search for $\nu_{\mu}\to\nu_{\tau}$
oscillations, consists of a nuclear emulsion target and electronic detectors.
In this paper, results on the production of charged particles in a small sample
of charged-current neutrino-- and anti-neutrino--nucleus interactions at high
energy are presented. For each event, the emission angle and the ionization
features of the charged particles produced in the interaction are recorded,
while the standard kinematic variables are reconstructed using the electronic
detectors. The average multiplicities for charged tracks, the pseudo-rapidity
distributions, the dispersion in the multiplicity of charged particles and the
KNO scaling are studied in different kinematical regions. A study of
quasi-elastic topologies performed for the first time in nuclear emulsions is
also reported. The results are presented in a form suitable for use in the
validation of Monte Carlo generators of neutrino--nucleus interactions.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:45:50 GMT"
},
{
"version": "v2",
"created": "Tue, 21 Aug 2007 15:12:51 GMT"
}
] | 2012-08-27T00:00:00 | [
[
"The CHORUS Collaboration",
"",
""
]
] |
0707.1587 | Ulrich Langenfeld | Ulrich Langenfeld | Constraints on Neutralino masses and mixings from Cosmology and Collider
Physics | PhD-Thesis, 101 pages | null | null | null | hep-ph | null | Bounds on cross section measurements of chargino pair production at LEP yield
a bound on the chargino mass. If the GUT relation is assumed, the lightest
neutralino must be heavier than $\approx 45 -50\GeV$. If no GUT relation is
assumed, no lower bound on the neutralino mass exists. I derive mass bounds on
the lightest neutralino from relic density measurements for relativistic and
non-relativistic neutralinos and I derive bounds on the selectron mass from the
observed limits on the cross section of the neutralino pair production process
$e^+e^-\to \x{1}\x{2}$ at LEP, if the lightest neutralino is massless. I
further discuss radiative neutralino production and its background at the
future ILC. Finally, I present a method to determine the neutralino couplings
to right and left handed selectrons and Z bosons from cross section
measurements of radiative neutralino production and neutralino pair production
at the ILC.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 09:53:47 GMT"
},
{
"version": "v2",
"created": "Thu, 9 Aug 2007 09:03:41 GMT"
}
] | 2007-08-09T00:00:00 | [
[
"Langenfeld",
"Ulrich",
""
]
] |
0707.1588 | Khoa Nguyen | Khoa D. Nguyen, Albert Guillen i Fabregas, Lars K. Rasmussen | A Tight Lower Bound to the Outage Probability of Discrete-Input
Block-Fading Channels | 22 pages, 4 figures. This work has been accepted for IEEE
Transactions on Information Theory and has been presented in part at the 2007
IEEE International Symposium on Information Theory, Nice, France, June 2007 | null | 10.1109/TIT.2007.907520 | null | cs.IT math.IT | null | In this correspondence, we propose a tight lower bound to the outage
probability of discrete-input Nakagami-m block-fading channels. The approach
permits an efficient method for numerical evaluation of the bound, providing an
additional tool for system design. The optimal rate-diversity trade-off for the
Nakagami-m block-fading channel is also derived and a tight upper bound is
obtained for the optimal coding gain constant.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 11:23:10 GMT"
}
] | 2016-11-15T00:00:00 | [
[
"Nguyen",
"Khoa D.",
""
],
[
"Fabregas",
"Albert Guillen i",
""
],
[
"Rasmussen",
"Lars K.",
""
]
] |
0707.1589 | Yonatan Sivan | Y. Sivan, G. Fibich, N.K. Efremidis, S. Bar-Ad | Analytic theory of narrow lattice solitons | null | null | 10.1088/0951-7715/21/3/008 | null | nlin.PS | null | The profiles of narrow lattice solitons are calculated analytically using
perturbation analysis. A stability analysis shows that solitons centered at a
lattice (potential) maximum are unstable, as they drift toward the nearest
lattice minimum. This instability can, however, be so weak that the soliton is
``mathematically unstable'' but ``physically stable''. Stability of solitons
centered at a lattice minimum depends on the dimension of the problem and on
the nonlinearity. In the subcritical and supercritical cases, the lattice does
not affect the stability, leaving the solitons stable and unstable,
respectively. In contrast, in the critical case (e.g., a cubic nonlinearity in
two transverse dimensions), the lattice stabilizes the (previously unstable)
solitons. The stability in this case can be so weak, however, that the soliton
is ``mathematically stable'' but ``physically unstable''.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 10:22:54 GMT"
},
{
"version": "v2",
"created": "Wed, 25 Jul 2007 11:46:35 GMT"
},
{
"version": "v3",
"created": "Mon, 21 Jan 2008 08:05:06 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sivan",
"Y.",
""
],
[
"Fibich",
"G.",
""
],
[
"Efremidis",
"N. K.",
""
],
[
"Bar-Ad",
"S.",
""
]
] |
0707.1590 | Tam\'as Borkovits | T. Borkovits, E. Forg\'acs-Dajka and Zs. Reg\'aly | Tidal and rotational effects in the perturbations of hierarchical triple
stellar systems. II. Eccentric systems - the case of AS Camelopardalis | 33 pages, 12 figures (reduced quality!), accepted for publication for
Astronomy and Astrophysics | null | 10.1051/0004-6361:20077793 | null | astro-ph | null | We study the perturbations of a relatively close third star on a tidally
distorted eccentric eclipsing binary. We consider both the observational
consequences of the variations of the orbital elements and the interactions of
the stellar rotation with the orbital revolution in the presence of
dissipation. We concentrate mainly on the effect of a hypothetical third
companion on both the real, and the observed apsidal motion period. We
investigate how the observed period derived mainly from some variants of the
O-C relates to the real apsidal motion period. We carried out both analytical
and numerical investigations and give the time variations of the orbital
elements of the binary both in the dynamical and the observational reference
frames. We give the direct analytical form of an eclipsing O-C affected
simultaneously by the mutual tidal forces and the gravitational interactions
with a tertiary. We also integrated numerically simultaneously the orbital and
rotational equations for the possible hierarchical triple stellar system AS
Camelopardalis. We find that there is a significant domain of the possible
hierarchical triple system configurations, where both the dynamical and the
observational effects tend to measure longer apsidal advance rate than is
expected theoretically. This happens when the mutual inclination of the close
and the wide orbits is large, and the orbital plane of the tertiary almost
coincides with the plane of the sky. We also obtain new numerical results on
the interaction of the orbital evolution and stellar rotation in such triplets.
The most important fact is that resonances might occur as the stellar
rotational rate varies during the dissipation-driven synchronization process...
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 10:53:24 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Borkovits",
"T.",
""
],
[
"Forgács-Dajka",
"E.",
""
],
[
"Regály",
"Zs.",
""
]
] |
0707.1591 | Andreas Nyffeler | Raghavendra Srikanth Hundi, Biswarup Mukhopadhyaya and Andreas
Nyffeler (Harish-Chandra Research Institute) | Invisibly decaying Higgs boson in the Littlest Higgs model with T-parity | 4 pages, 2 figures, Latex (stylefiles included); Talk presented by
A.N. at the International Workshop on Theoretical High Energy Physics (IWTHEP
2007), Roorkee, India, 15-20 March 2007, to appear in the proceedings | AIPConf.Proc.939:59-62,2007 | 10.1063/1.2803787 | HRI-P-07-07-001 | hep-ph | null | We show that there are regions in the parameter space of the Littlest Higgs
model with T-parity, allowed by electroweak precision data, where the Higgs
boson can decay invisibly into a pair of heavy photons A_H with a substantial
branching ratio. For a symmetry breaking scale f in the range 450-600 GeV, the
BR(H -> A_H A_H) can be up to 95% for an intermediate mass Higgs, and from 20%
down to a few percents for a Higgs boson of mass 200 GeV or above. The total
decay width of the Higgs boson can thereby be enhanced by an order of magnitude
compared to the Standard Model for Higgs masses around 130 GeV.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 10:54:30 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hundi",
"Raghavendra Srikanth",
"",
"Harish-Chandra Research Institute"
],
[
"Mukhopadhyaya",
"Biswarup",
"",
"Harish-Chandra Research Institute"
],
[
"Nyffeler",
"Andreas",
"",
"Harish-Chandra Research Institute"
]
] |
0707.1592 | Kazem Azizi | T. M. Aliev, K. Azizi, A. Ozpineci | Light Cone QCD Sum Rules Analysis of the Axial N -> Delta Transition
Form Factors | 31 Pages, 9 Figures | Nucl.Phys.A799:105-126,2008 | 10.1016/j.nuclphysa.2007.11.006 | null | hep-ph | null | The axial N-> Delta(1232) transition form factors are calculated within the
light cone QCD sum rules method. A comparison of our results with predictions
of lattice theory and quark model calculations is pre- sented.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:34:32 GMT"
},
{
"version": "v2",
"created": "Tue, 28 Aug 2007 11:46:29 GMT"
},
{
"version": "v3",
"created": "Tue, 30 Oct 2007 09:22:06 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Aliev",
"T. M.",
""
],
[
"Azizi",
"K.",
""
],
[
"Ozpineci",
"A.",
""
]
] |
0707.1593 | A. Cooper-Sarkar | A M Cooper-Sarkar | Impact of and constraints on PDFs at LHC | 8 pages, 8 figures, to be published in the Proceedings of the XV
Workshop on Deep Inelastic Scattering, DIS07, Munich | null | null | null | hep-ph hep-ex | null | Uncertainties on parton distribution functions (PDFs) compromise discovery at
the LHC for any new physics which can be described as a contact-interaction.
PDF uncertainties also limit our ability to use W and Z cross-sections as an
accurate luminosity monitor. The impact of the current level of PDF uncertainty
on LHC physics is reviewed and the possibility of reducing this uncertainty
using LHC data is investigated.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 11:02:03 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Cooper-Sarkar",
"A M",
""
]
] |
0707.1594 | Peter Coles | Jun Pan (1,2), Peter Coles (2,3) and Istvan Szapudi (4) ((1) Purple
Mountain Observatory, Nanjing, China; (2) School of Physics & Astronomy,
University of Nottingham, UK; (3) School of Physics & Astronomy, Cardiff
University, UK; (4) Institute for Astronomy, University of Hawaii, USA) | Scale Transformations, Tree-level Perturbation Theory, and the
Cosmological Matter Bispectrum | 6 pages, 3 figures; revised version accepted for publication in MNRAS | null | 10.1111/j.1365-2966.2007.12494.x | null | astro-ph | null | Scale transformations have played an extremely successful role in studies of
cosmological large-scale structure by relating the non-linear spectrum of
cosmological density fluctuations to the linear primordial power at longer
wavelengths. Here we generalize this approach to investigate the usefulness of
scale transformations for nonlinear higher-order statistics, specifically the
bispectrum. We find that the bispectrum predicted by perturbation theory at
tree-level can be rescaled to match the results of full numerical simulations
in the weakly and intermediately nonlinear regimes, especially at high
redshifts, with an accuracy that is surprising given the simplicity of the
procedure used. This discovery not only offers a simple practical way of
calculating the matter bispectrum, but also suggests that scale transformations
may yet yield even deeper insights into the physics of hierarchical clustering.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 11:05:08 GMT"
},
{
"version": "v2",
"created": "Wed, 19 Sep 2007 13:16:56 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Pan",
"Jun",
""
],
[
"Coles",
"Peter",
""
],
[
"Szapudi",
"Istvan",
""
]
] |
0707.1595 | Eran Palti | Eran Palti | Low Energy Supersymmetry from Non-Geometry | 36pp; v2 references added, minor clarifications, JHEP version | JHEP 0710:011,2007 | 10.1088/1126-6708/2007/10/011 | null | hep-th | null | We study a class of flux compactifications that have all the moduli
stabilised, a high (GUT) string scale and a low (TeV) gravitino mass that is
generated dynamically. These non-geometric compactifications correspond to type
II string theories on SU(3)xSU(3) structure orientifolds. The resulting
superpotentials admit, excluding non-perturbative effects, supersymmetric
Minkowski vacua with any number of moduli stabilised. We argue that
non-perturbative effects are present and introduce terms in the superpotential
that are exponentially suppressed by the same moduli that appear
perturbatively. These deform the supersymmetric Minkowski vacua to
supersymmetric AdS vacua with an exponentially small gravitino mass. The
resulting vacua allow for low scale supersymmetry breaking which can be
realised by a number of mechanisms.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 11:15:51 GMT"
},
{
"version": "v2",
"created": "Mon, 1 Oct 2007 17:10:56 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Palti",
"Eran",
""
]
] |
0707.1596 | Ulrich Jentschura | E. Caliceti, M. Meyer-Hermann, P. Ribeca, A. Surzhykov, U. D.
Jentschura | From Useful Algorithms for Slowly Convergent Series to Physical
Predictions Based on Divergent Perturbative Expansions | 119 pages, LaTeX | Phys.Rep. 446 (2007) 1-96 | 10.1016/j.physrep.2007.03.003 | null | physics.comp-ph physics.atom-ph | null | This review is focused on the borderline region of theoretical physics and
mathematics. First, we describe numerical methods for the acceleration of the
convergence of series. These provide a useful toolbox for theoretical physics
which has hitherto not received the attention it actually deserves. The
unifying concept for convergence acceleration methods is that in many cases,
one can reach much faster convergence than by adding a particular series term
by term. In some cases, it is even possible to use a divergent input series,
together with a suitable sequence transformation, for the construction of
numerical methods that can be applied to the calculation of special functions.
This review both aims to provide some practical guidance as well as a
groundwork for the study of specialized literature. As a second topic, we
review some recent developments in the field of Borel resummation, which is
generally recognized as one of the most versatile methods for the summation of
factorially divergent (perturbation) series. Here, the focus is on algorithms
which make optimal use of all information contained in a finite set of
perturbative coefficients. The unifying concept for the various aspects of the
Borel method investigated here is given by the singularities of the Borel
transform, which introduce ambiguities from a mathematical point of view and
lead to different possible physical interpretations. The two most important
cases are: (i) the residues at the singularities correspond to the decay width
of a resonance, and (ii) the presence of the singularities indicates the
existence of nonperturbative contributions which cannot be accounted for on the
basis of a Borel resummation and require generalizations toward resurgent
expansions. Both of these cases are illustrated by examples.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:03:01 GMT"
}
] | 2013-09-10T00:00:00 | [
[
"Caliceti",
"E.",
""
],
[
"Meyer-Hermann",
"M.",
""
],
[
"Ribeca",
"P.",
""
],
[
"Surzhykov",
"A.",
""
],
[
"Jentschura",
"U. D.",
""
]
] |
0707.1597 | Stefan Groot Nibbelink | Stefan Groot Nibbelink, Tae-Won Ha, Michele Trapletti | Toric Resolutions of Heterotic Orbifolds | 1+34 pages LaTeX with 5 figures, some wording changed and references
added | Phys.Rev.D77:026002,2008 | 10.1103/PhysRevD.77.026002 | HD-THEP-07-18, SIAS-CMTP-07-4 | hep-th | null | We investigate resolutions of heterotic orbifolds using toric geometry. Our
starting point is provided by the recently constructed heterotic models on
explicit blowup of C^n/Z_n singularities. We show that the values of the
relevant integrals, computed there, can be obtained as integrals of divisors
(complex codimension one hypersurfaces) interpreted as (1,1)-forms in toric
geometry. Motivated by this we give a self contained introduction to toric
geometry for non-experts, focusing on those issues relevant for the
construction of heterotic models on toric orbifold resolutions. We illustrate
the methods by building heterotic models on the resolutions of C^2/Z_3, C^3/Z_4
and C^3/Z_2xZ_2'. We are able to obtain a direct identification between them
and the known orbifold models. In the C^3/Z_2xZ_2' case we observe that, in
spite of the existence of two inequivalent resolutions, fully consistent blowup
models of heterotic orbifolds can only be constructed on one of them.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:12:39 GMT"
},
{
"version": "v2",
"created": "Tue, 24 Jul 2007 12:48:32 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Nibbelink",
"Stefan Groot",
""
],
[
"Ha",
"Tae-Won",
""
],
[
"Trapletti",
"Michele",
""
]
] |
0707.1598 | Andrey Gorbach | A. V. Gorbach and D. V. Skryabin | Theory of radiation trapping by the accelerating solitons in optical
fibers | Several misprints in text and formulas corrected. 10 pages, 9
figures, submitted to Phys. Rev. A | null | 10.1103/PhysRevA.76.053803 | null | physics.optics nlin.PS | null | We present a theory describing trapping of the normally dispersive radiation
by the Raman solitons in optical fibers. Frequency of the radiation component
is continuously blue shifting, while the soliton is red shifting. Underlying
physics of the trapping effect is in the existence of the inertial gravity-like
force acting on light in the accelerating frame of reference. We present
analytical calculations of the rate of the opposing frequency shifts of the
soliton and trapped radiation and find it to be greater than the rate of the
red shift of the bare Raman soliton. Our findings are essential for
understanding of the continuous shift of the high frequency edge of the
supercontinuum spectra generated in photonic crystal fibers towards higher
frequencies.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:13:53 GMT"
},
{
"version": "v2",
"created": "Wed, 29 Aug 2007 07:53:51 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Gorbach",
"A. V.",
""
],
[
"Skryabin",
"D. V.",
""
]
] |
0707.1599 | Volker Puppe | Matthias Kreck and Volker Puppe | Involutions on 3-Manifolds and Self-dual, Binary Codes | 9 pages | null | null | null | math.AT | null | We study a correspondence between orientation reversing involutions on
compact 3-manifolds with only isolated fixed points and binary, self-dual
codes. We show in particular that every such code can be obtained from such an
involution. We further relate doubly even codes to Pin^- -structures and
Spin-manifolds.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:38:46 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Kreck",
"Matthias",
""
],
[
"Puppe",
"Volker",
""
]
] |
0707.1600 | Artur Lopes O. | B. P. Olbermann, Silvia R. C. Lopes and Artur O. Lopes | Parameter Estimation in Manneville-Pomeau Processes | null | null | null | null | math.ST math.DS stat.TH | null | In this work we study a class of stochastic processes $\{X_t\}_{t\in\N}$,
where $X_t = (\phi \circ T_s^t)(X_0)$ is obtained from the iterations of the
transformation T_s, invariant for an ergodic probability \mu_s on [0,1] and a
continuous by part function $\phi:[0,1] \to \R$. We consider here $T_s:[0,1]\to
[0,1]$ the Manneville-Pomeau transformation. The autocorrelation function of
the resulting process decays hyperbolically (or polynomially) and we obtain
efficient methods to estimate the parameter s from a finite time series. As a
consequence we also estimate the rate of convergence of the autocorrelation
decay of these processes. We compare different estimation methods based on the
periodogram function, on the smoothed periodogram function, on the variance of
the partial sum and on the wavelet theory.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:19:39 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Olbermann",
"B. P.",
""
],
[
"Lopes",
"Silvia R. C.",
""
],
[
"Lopes",
"Artur O.",
""
]
] |
0707.1601 | Pamela Morehouse | A. Lopez, et al, CLEO Collaboration | Measurement of Prominent eta Decay Branching Fractions | 11 pages postscript,also available through
http://www.lns.cornell.edu/public/CLNS/2007/, Submitted to PRL | Phys.Rev.Lett.99:122001,2007 | 10.1103/PhysRevLett.99.122001 | CLNS 07/2002, CLEO 07-10 | hep-ex | null | The decay psi(2S) --> eta J/psi is used to measure, for the first time, all
prominent eta-meson branching fractions with the same experiment in the same
dataset, thereby providing a consistent treatment of systematics across
branching fractions. We present results for eta decays to gamma gamma,
pi+pi-pi0, 3 pi0, pi+ pi- gamma, and e+ e- gamma, accounting for 99.9% of all
eta decays. The precisions for several of the branching fractions and their
ratios are improved. Two channels, pi+ pi- gamma and e+ e- gamma, show results
that differ at the level of three standard deviations from those previously
determined.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:19:50 GMT"
}
] | 2010-04-08T00:00:00 | [
[
"Lopez",
"A.",
""
],
[
"Collaboration",
"CLEO",
""
]
] |
0707.1602 | Jason W. T. Hessels | J.W.T. Hessels (Univ. of Amsterdam/McGill), S.M. Ransom (NRAO), I.H.
Stairs (UBC), V.M. Kaspi (McGill), P.C.C. Freire (NAIC) | A 1.4-GHz Arecibo Survey for Pulsars in Globular Clusters | 27 pages, 6 tables, 5 figures Submitted to ApJ, includes referee
comments | null | 10.1086/521780 | null | astro-ph | null | We have surveyed all 22 known Galactic globular clusters observable with the
Arecibo radio telescope and within 70kpc of the Sun for radio pulsations at
~1.4GHz. Data were taken with the Wideband Arecibo Pulsar Processor, which
provided the large bandwidth and high time and frequency resolution needed to
detect fast-spinning, faint pulsars. We have also employed advanced search
techniques to maintain sensitivity to short orbital period binaries. These
searches have discovered 11 new millisecond pulsars and 2 promising candidates
in 5 clusters, almost doubling the population of pulsars in the Arecibo-visible
globular clusters. Ten of these new pulsars are in binary systems, and 3 are
eclipsing. This survey has discovered significantly more very fast-spinning
pulsars (P_spin <~ 4ms) and short orbital period systems (P_orb <~ 6hr) than
previous surveys of the same clusters. We discuss some properties of these
systems, as well as some characteristics of the globular cluster pulsar
population in general, particularly its luminosity distribution.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:59:05 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Hessels",
"J. W. T.",
"",
"Univ. of Amsterdam/McGill"
],
[
"Ransom",
"S. M.",
"",
"NRAO"
],
[
"Stairs",
"I. H.",
"",
"UBC"
],
[
"Kaspi",
"V. M.",
"",
"McGill"
],
[
"Freire",
"P. C. C.",
"",
"NAIC"
]
] |
0707.1603 | Luiz Agostinho Ferreira | L. A. Ferreira and Wojtek J. Zakrzewski | A simple formula for the conserved charges of soliton theories | 26 pages, plain latex, 1 eps figure, In this second version the
example of the mKdV equation was added in section 4.1, and a paragraph was
added in the introduction. Version to be published in JHEP (Journal of High
Energy Physics) | JHEP 0709:015,2007 | 10.1088/1126-6708/2007/09/015 | null | hep-th math-ph math.MP nlin.SI | null | We present a simple formula for all the conserved charges of soliton
theories, evaluated on the solutions belonging to the orbit of the vacuum under
the group of dressing transformations. For pedagogical reasons we perform the
explicit calculations for the case of the sine-Gordon model, taken as a
prototype of soliton theories. We show that the energy and momentum are
boundary terms for all the solutions on the orbit of the vacuum. That orbit
includes practically all the solutions of physical interest, namely solitons,
multi-solitons, breathers, and combinations of solitons and breathers. The
example of the mKdV equation is also given explicitly.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:48:12 GMT"
},
{
"version": "v2",
"created": "Mon, 27 Aug 2007 20:13:46 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Ferreira",
"L. A.",
""
],
[
"Zakrzewski",
"Wojtek J.",
""
]
] |
0707.1604 | Zhiqiang Li | Z. Q. Li, V. Podzorov, N. Sai, M. C. Martin, M. E. Gershenson, M. Di
Ventra, and D. N. Basov | Light Quasiparticles Dominate Electronic Transport in Molecular Crystal
Field-Effect Transistors | 4 pages, 4 figures | Phys. Rev. Lett. 99, 016403 (2007) | 10.1103/PhysRevLett.99.016403 | null | cond-mat.mtrl-sci cond-mat.soft | null | We report on an infrared spectroscopy study of mobile holes in the
accumulation layer of organic field-effect transistors based on rubrene single
crystals. Our data indicate that both transport and infrared properties of
these transistors at room temperature are governed by light quasiparticles in
molecular orbital bands with the effective masses m* comparable to free
electron mass. Furthermore, the m* values inferred from our experiments are in
agreement with those determined from band structure calculations. These
findings reveal no evidence for prominent polaronic effects, which is at
variance with the common beliefs of polaron formation in molecular solids.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 00:14:44 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Li",
"Z. Q.",
""
],
[
"Podzorov",
"V.",
""
],
[
"Sai",
"N.",
""
],
[
"Martin",
"M. C.",
""
],
[
"Gershenson",
"M. E.",
""
],
[
"Di Ventra",
"M.",
""
],
[
"Basov",
"D. N.",
""
]
] |
0707.1605 | Jan Draisma | Karin Baur and Jan Draisma | Secant dimensions of low-dimensional homogeneous varieties | 25 pages, many pictures | Adv. Geom. 10 (2010), no. 1, 1-29 | null | null | math.AG math.RT | null | We completely describe the higher secant dimensions of all connected
homogeneous projective varieties of dimension at most 3, in all possible
equivariant embeddings. In particular, we calculate these dimensions for all
Segre-Veronese embeddings of P^1 * P^1, P^1 * P^1 * P^1, and P^2 * P^1, as well
as for the variety F of incident point-line pairs in P^2. For P^2 * P^1 and F
the results are new, while the proofs for the other two varieties are more
compact than existing proofs. Our main tool is the second author's tropical
approach to secant dimensions.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 12:51:40 GMT"
}
] | 2010-11-18T00:00:00 | [
[
"Baur",
"Karin",
""
],
[
"Draisma",
"Jan",
""
]
] |
0707.1606 | Rui Dong | Rui Dong | Exchangeable partitions derived from Markovian coalescents with
simultaneous multiple collisions | null | null | null | null | math.PR | null | Kingman derived the Ewens sampling formula for random partitions from the
genealogy model defined by a Poisson process of mutations along lines of
descent governed by a simple coalescent process. M\"ohle described the
recursion which determines the generalization of the Ewens sampling formula
when the lines of descent are governed by a coalescent with multiple
collisions. In a recent work by Dong, Gnedin and Pitman, authors exploit an
analogy with the theory of regenerative composition and partition structures,
and provide various characterizations of the associated exchangeable random
partitions. This paper gives parallel results for the further generalized model
with lines of descent following a coalescent with simultaneous multiple
collisions.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:23:28 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Dong",
"Rui",
""
]
] |
0707.1607 | Erik Schnetter | Erik Schnetter, Christian D. Ott, Gabrielle Allen, Peter Diener, Tom
Goodale, Thomas Radke, Edward Seidel, John Shalf | Cactus Framework: Black Holes to Gamma Ray Bursts | 16 pages, 4 figures. To appear in Petascale Computing: Algorithms and
Applications, Ed. D. Bader, CRC Press LLC (2007) | null | null | null | cs.DC | null | Gamma Ray Bursts (GRBs) are intense narrowly-beamed flashes of gamma-rays of
cosmological origin. They are among the most scientifically interesting
astrophysical systems, and the riddle concerning their central engines and
emission mechanisms is one of the most complex and challenging problems of
astrophysics today. In this article we outline our petascale approach to the
GRB problem and discuss the computational toolkits and numerical codes that are
currently in use and that will be scaled up to run on emerging petaflop scale
computing platforms in the near future.
Petascale computing will require additional ingredients over conventional
parallelism. We consider some of the challenges which will be caused by future
petascale architectures, and discuss our plans for the future development of
the Cactus framework and its applications to meet these challenges in order to
profit from these new architectures.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:01:50 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Schnetter",
"Erik",
""
],
[
"Ott",
"Christian D.",
""
],
[
"Allen",
"Gabrielle",
""
],
[
"Diener",
"Peter",
""
],
[
"Goodale",
"Tom",
""
],
[
"Radke",
"Thomas",
""
],
[
"Seidel",
"Edward",
""
],
[
"Shalf",
"John",
""
]
] |
0707.1608 | Roberto Giambo' | Roberto Giamb\'o, Sara Quintavalle | Dimensional dependence of naked singularity formation in spherical
gravitational collapse | 11 pages, to appear with minor modifications on Class. Quantum Grav | Class.Quant.Grav.25:145003,2008 | 10.1088/0264-9381/25/14/145003 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The complete spectrum of the endstates - naked singularities, or blackholes -
of gravitational collapse is analyzed for a wide class of $N$-dimensional
spacetimes in spherical symmetry, which includes and generalizes the dust
solutions and the case of vanishing radial stresses. The final fate of the
collapse is shown to be fully determined by the local behavior of a single
scalar function and by the dimension $N$ of the spacetime. In particular, the
``critical'' behavior of the N=4 spacetimes, where a sort of phase transition
from black hole to naked singularity can occur, is still present if N=5 but
does not occur if $N > 5$, independently from the initial data of the collapse.
Physically, the results turn out to be related to the kinematical properties of
the considered solutions.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:04:18 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jun 2008 17:12:52 GMT"
}
] | 2010-03-24T00:00:00 | [
[
"Giambó",
"Roberto",
""
],
[
"Quintavalle",
"Sara",
""
]
] |
0707.1609 | Zoran Skoda | Zoran \v{S}koda | Equivariant monads and equivariant lifts versus a 2-category of
distributive laws | preliminary version | null | null | null | math.CT | null | Fix a monoidal category C. The 2-category of monads in the 2-category of
C-actegories, colax C-equivarant functors, and C-equivariant natural
transformations of colax functors, may be recast in terms of pairs consisting
of a usual monad and a distributive law between the monad and the action of C,
morphisms of monads respecting the distributive law, and transformations of
monads satisfying some compatibility with the actions and distributive laws
involved. The monads in this picture may be generalized to actions of monoidal
categories, and actions of PRO-s in particular. If C is a PRO as well, then in
special cases one gets various distributive laws of a given classical type, for
example between a comonad and an endofunctor or between a monad and a comonad.
The usual pentagons are in general replaced by multigons, and there are also
``mixed'' multigons involving two distinct distributive laws. Beck's bijection
between the distributive laws and lifts of one monad to the Eilenberg-Moore
category of another monad is here extended to an isomorphism of 2-categories.
The lifts of maps of above mentioned pairs are colax C-equivariant. We finish
with a short treatment of relative distributive laws between two pseudoalgebra
structures which are relative with respect to the distributivity of two
pseudomonads involved, what gives a hint toward the generalizations.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:06:00 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Škoda",
"Zoran",
""
]
] |
0707.1610 | Ayse Ozlem Sezerman | C. Atilgan, A. O. Aykut, A. R. Atilgan | How a Vicinal Layer of Solvent Modulates the Dynamics of Proteins | null | Biophys. J. 2008 94: 79-89 | 10.1529/biophysj.107.116426 | null | cond-mat.soft | null | The dynamics of a folded protein is studied in water and glycerol at a series
of temperatures below and above their respective dynamical transition. The
system is modeled in two distinct states whereby the protein is decoupled from
the bulk solvent at low temperatures, and communicates with it through a
vicinal layer at physiological temperatures. A linear viscoelastic model
elucidates the less-than-expected increase in the relaxation times observed in
the backbone dynamics of the protein. The model further explains the increase
in the flexibility of the protein once the transition takes place and the
differences in the flexibility under the different solvent environments.
Coupling between the vicinal layer and the protein fluctuations is necessary to
interpret these observations. The vicinal layer is postulated to form once a
threshold for the volumetric fluctuations in the protein to accommodate
solvents of different sizes is reached. Compensation of entropic-energetic
contributions from the protein-coupled vicinal layer quantifies the scaling of
the dynamical transition temperatures in various solvents. The protein adapts
different conformational routes for organizing the required coupling to a
specific solvent, which is achieved by adjusting the amount of conformational
jumps in the surface-group dihedrals.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:09:43 GMT"
}
] | 2008-09-23T00:00:00 | [
[
"Atilgan",
"C.",
""
],
[
"Aykut",
"A. O.",
""
],
[
"Atilgan",
"A. R.",
""
]
] |
0707.1611 | Tamas Budavari | Tamas Budavari and Alexander S. Szalay | Probabilistic Cross-Identification of Astronomical Sources | Accepted for publication in the Astrophysical Journal, 8 pages, 1
figure, emulateapj w/ apjfonts | null | 10.1086/587156 | null | astro-ph | null | We present a general probabilistic formalism for cross-identifying
astronomical point sources in multiple observations. Our Bayesian approach,
symmetric in all observations, is the foundation of a unified framework for
object matching, where not only spatial information, but physical properties,
such as colors, redshift and luminosity, can also be considered in a natural
way. We provide a practical recipe to implement an efficient recursive
algorithm to evaluate the Bayes factor over a set of catalogs with known
circular errors in positions. This new methodology is crucial for studies
leveraging the synergy of today's multi-wavelength observations and to enter
the time-domain science of the upcoming survey telescopes.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:10:52 GMT"
},
{
"version": "v2",
"created": "Thu, 20 Sep 2007 16:59:34 GMT"
},
{
"version": "v3",
"created": "Mon, 11 Feb 2008 20:06:07 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Budavari",
"Tamas",
""
],
[
"Szalay",
"Alexander S.",
""
]
] |
0707.1612 | Julien Malzac | Julien Malzac | Accretion disc coronae in black hole binaries | 8 pages, 1 figure; invited review at the 'Coronae of Stars and
Accretion Disks' conference, Bonn, 12-13 December 2006 | Mem.Soc.Ast.It.78:382,2007 | null | null | astro-ph | null | Most of the luminosity of accreting black hole is emitted in the X-ray band.
This radiation is believed to emerge, through inverse Compton process, from a
hot (Te ~ 10^8 -10^9 K) optically thin (Thomson optical depth ~ 1) plasma
probably located in the immediate vicinity of the black hole. The mechanisms at
work in this so called Compton corona can be unveiled through hard X-ray
observations which have revealed a rich phenomenology. Depending on luminosity
different spectral states are observed suggesting that the nature and geometry
of the corona depends on mass accretion rate. In many instances the spectral
behaviour as a function of luminosity shows some degree of hysteresis. The
mechanisms triggering the transition between spectral states is very unclear
although it could be related to an evaporation/condensation equilibrium in an
accretion disc corona system. From the observation of correlation between the
X-ray and radio band, it appears that the Compton corona is intimately related
to the formation of compact jets and probably constitutes the base of the jet.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:20:38 GMT"
}
] | 2009-06-25T00:00:00 | [
[
"Malzac",
"Julien",
""
]
] |
0707.1613 | Priya Hasan | Priya Hasan | Morphologies of AGN host galaxies using HST/ACS in the CDFS-GOODS field | pdflatex, accepted in ApSS. revisions in text | Astrophys.Space Sci.312:63-77,2007 | 10.1007/s10509-007-9648-8 | null | astro-ph | null | Using HST/ACS images in four bands F435W, F606W, F775W and F850LP, we
identify optical counterparts to the X-ray sources in the Chandra Deep Field
South in the GOODS South field. A detailed study has been made of these sources
to study their morphological types. We use methods like decomposition of galaxy
luminosity profiles, color maps and visual inspection of 192 galaxies which are
identified as possible optical counterparts of Chandra X-ray sources in the
CDFS-GOODS field. We find that most moderate luminosity AGN hosts are bulge
dominated in the redshift range (z \approx 0.4-1.3), but not
merging/interacting galaxies. This implies probable fueling of the moderate
luminosity AGN by mechanisms other than those merger driven.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 06:03:20 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Jul 2007 06:21:38 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Hasan",
"Priya",
""
]
] |
0707.1614 | Antonios Zagaris | A. Zagaris, C. W. Gear, T. J. Kaper, I. G. Kevrekidis | Analysis of the accuracy and convergence of equation-free projection to
a slow manifold | null | null | 10.1051/m2an/2009026 | null | math.DS math.NA | null | In [C.W. Gear, T.J. Kaper, I.G. Kevrekidis, and A. Zagaris, Projecting to a
Slow Manifold: Singularly Perturbed Systems and Legacy Codes, SIAM J. Appl.
Dyn. Syst. 4 (2005) 711-732], we developed a class of iterative algorithms
within the context of equation-free methods to approximate low-dimensional,
attracting, slow manifolds in systems of differential equations with multiple
time scales. For user-specified values of a finite number of the observables,
the m-th member of the class of algorithms (m = 0, 1, ...) finds iteratively an
approximation of the appropriate zero of the (m+1)-st time derivative of the
remaining variables and uses this root to approximate the location of the point
on the slow manifold corresponding to these values of the observables. This
article is the first of two articles in which the accuracy and convergence of
the iterative algorithms are analyzed. Here, we work directly with explicit
fast--slow systems, in which there is an explicit small parameter, epsilon,
measuring the separation of time scales. We show that, for each m = 0, 1, ...,
the fixed point of the iterative algorithm approximates the slow manifold up to
and including terms of O(epsilon^m). Moreover, for each m, we identify
explicitly the conditions under which the m-th iterative algorithm converges to
this fixed point. Finally, we show that when the iteration is unstable (or
converges slowly) it may be stabilized (or its convergence may be accelerated)
by application of the Recursive Projection Method. Alternatively, the
Newton-Krylov Generalized Minimal Residual Method may be used. In the
subsequent article, we will consider the accuracy and convergence of the
iterative algorithms for a broader class of systems-in which there need not be
an explicit small parameter-to which the algorithms also apply.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:24:26 GMT"
}
] | 2010-09-17T00:00:00 | [
[
"Zagaris",
"A.",
""
],
[
"Gear",
"C. W.",
""
],
[
"Kaper",
"T. J.",
""
],
[
"Kevrekidis",
"I. G.",
""
]
] |
0707.1615 | Hong Jiang | Hong Jiang and Eberhard Engel | Random-phase-approximation-based correlation energy functionals:
Benchmark results for atoms | 11 pages, 7 figures | null | 10.1063/1.2795707 | null | cond-mat.other | null | The random phase approximation (RPA) for the correlation energy functional of
density functional theory has recently attracted renewed interest. Formulated
in terms of the Kohn-Sham (KS) orbitals and eigenvalues, it promises to resolve
some of the fundamental limitations of the local density and generalized
gradient approximations, as for instance their inability to account for
dispersion forces. First results for atoms, however, indicate that the RPA
overestimates correlation effects as much as the orbital-dependent functional
obtained by a second order perturbation expansion on the basis of the KS
Hamiltonian. In this contribution, three simple extensions of the RPA are
examined, (a) its augmentation by an LDA for short-range correlation, (b) its
combination with the second order exchange term, and (c) its combination with a
partial resummation of the perturbation series including the second order
exchange. It is found that the ground state and correlation energies as well as
the ionization potentials resulting from the extensions (a) and (c) for closed
sub-shell atoms are clearly superior to those obtained with the unmodified RPA.
Quite some effort is made to ensure highly converged RPA data, so that the
results may serve as benchmark data. The numerical techniques developed in this
context, in particular for the inherent frequency integration, should also be
useful for applications of RPA-type functionals to more complex systems.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:28:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Jiang",
"Hong",
""
],
[
"Engel",
"Eberhard",
""
]
] |
0707.1616 | Michael J. Barber | Michael J. Barber | Modularity and community detection in bipartite networks | RevTex 4, 11 pages, 3 figures, 1 table; modest extensions to content | Phys. Rev. E 76, 066102 (2007) | 10.1103/PhysRevE.76.066102 | null | physics.data-an cond-mat.stat-mech physics.soc-ph | null | The modularity of a network quantifies the extent, relative to a null model
network, to which vertices cluster into community groups. We define a null
model appropriate for bipartite networks, and use it to define a bipartite
modularity. The bipartite modularity is presented in terms of a modularity
matrix B; some key properties of the eigenspectrum of B are identified and used
to describe an algorithm for identifying modules in bipartite networks. The
algorithm is based on the idea that the modules in the two parts of the network
are dependent, with each part mutually being used to induce the vertices for
the other part into the modules. We apply the algorithm to real-world network
data, showing that the algorithm successfully identifies the modular structure
of bipartite networks.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:16:51 GMT"
},
{
"version": "v2",
"created": "Tue, 11 Sep 2007 12:35:13 GMT"
},
{
"version": "v3",
"created": "Mon, 5 Nov 2007 13:21:27 GMT"
}
] | 2007-12-12T00:00:00 | [
[
"Barber",
"Michael J.",
""
]
] |
0707.1617 | Hallouin Emmanuel | Emmanuel Hallouin | Computation of the cover of Shimura curves $X_0(2) \to X(1)$ for the
cyclic cubic field of discriminant 13^2 | null | null | null | null | math.NT math.AG | null | We compute the canonical model of the cover of Shimura curves $X_0(2) \to
X(1)$ for the cubic field of discriminant 13^2 described at the end of Elkies'
paper "Shimura curves for level 3 subgroups of the (2,3,7) triangle group".
Last, we list the coordinates of some rational CM points on X(1).
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:30:57 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Hallouin",
"Emmanuel",
""
]
] |
0707.1618 | Per Ola Kristensson | Per Ola Kristensson, Nils Dahlback, Daniel Anundi, Marius Bjornstad,
Hanna Gillberg, Jonas Haraldsson, Ingrid Martensson, Matttias Nordvall,
Josefin Stahl | The Trade-offs with Space Time Cube Representation of Spatiotemporal
Patterns | null | null | null | null | cs.HC cs.GR | null | Space time cube representation is an information visualization technique
where spatiotemporal data points are mapped into a cube. Fast and correct
analysis of such information is important in for instance geospatial and social
visualization applications. Information visualization researchers have
previously argued that space time cube representation is beneficial in
revealing complex spatiotemporal patterns in a dataset to users. The argument
is based on the fact that both time and spatial information are displayed
simultaneously to users, an effect difficult to achieve in other
representations. However, to our knowledge the actual usefulness of space time
cube representation in conveying complex spatiotemporal patterns to users has
not been empirically validated. To fill this gap we report on a
between-subjects experiment comparing novice users error rates and response
times when answering a set of questions using either space time cube or a
baseline 2D representation. For some simple questions the error rates were
lower when using the baseline representation. For complex questions where the
participants needed an overall understanding of the spatiotemporal structure of
the dataset, the space time cube representation resulted in on average twice as
fast response times with no difference in error rates compared to the baseline.
These results provide an empirical foundation for the hypothesis that space
time cube representation benefits users when analyzing complex spatiotemporal
patterns.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:39:34 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Kristensson",
"Per Ola",
""
],
[
"Dahlback",
"Nils",
""
],
[
"Anundi",
"Daniel",
""
],
[
"Bjornstad",
"Marius",
""
],
[
"Gillberg",
"Hanna",
""
],
[
"Haraldsson",
"Jonas",
""
],
[
"Martensson",
"Ingrid",
""
],
[
"Nordvall",
"Matttias",
""
],
[
"Stahl",
"Josefin",
""
]
] |
0707.1619 | Doug Welch | D. L. Welch, Geoffrey C. Clayton, Amy Campbell, M. J. Barlow, Ben E.
K. Sugerman, Margaret Meixner, and S. H. R. Bank | An Extremely Bright Echo Associated With SN 2002hh | 24 pages, 6 figures. Accepted for publication in the ApJ | null | 10.1086/521542 | null | astro-ph | null | We present new, very late-time optical photometry and spectroscopy of the
interesting Type II-P supernova, SN 2002hh, in NGC 6946. Gemini/GMOS-N has been
used to acquire visible spectra at six epochs between 2004 August and 2006
July, following the evolution of the SN from age 661 to 1358 days. Few optical
spectra of Type II supernovae with ages greater than one year exist. In
addition, g'r'i' images were acquired at all six epochs. The spectral and
photometric evolution of SN 2002hh has been very unusual. Measures of the
brightness of this SN, both in the R and I bands as well as in the H-alpha
emission flux, show no significant fading over an interval of nearly two years.
The most straightforward explanation for this behavior is that the light being
measured comes not only from the SN itself but also from an echo off of nearby
dust. Echoes have been detected previously around several SNe but these echoes,
at their brightest, were ~8 mag below the maximum brightness of the SN. At V~21
mag, the putative echo dominates the light of SN 2002hh and is only ~4 mag
below the outburst's peak brightness. There is an estimated 6 magnitudes of
total extinction in V towards SN 2002hh. The proposed explanation of a
differential echo/SN absorption is inconsistent with the observed BVRI colors.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:50:25 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Welch",
"D. L.",
""
],
[
"Clayton",
"Geoffrey C.",
""
],
[
"Campbell",
"Amy",
""
],
[
"Barlow",
"M. J.",
""
],
[
"Sugerman",
"Ben E. K.",
""
],
[
"Meixner",
"Margaret",
""
],
[
"Bank",
"S. H. R.",
""
]
] |
0707.1620 | Harold U. Baranger | D. Herman, T. T. Ong, Gonzalo Usaj, H. Mathur, and H. U. Baranger | Level Spacings in Random Matrix Theory and Coulomb Blockade Peaks in
Quantum Dots | 15 pages, minor changes, published version | Phys. Rev. B 76, 195448 (2007) | 10.1103/PhysRevB.76.195448 | null | cond-mat.mes-hall | null | We obtain analytic formulae for the spacing between conductance peaks in the
Coulomb blockade regime, based on the universal Hamiltonian model of quantum
dots. New random matrix theory results are developed in order to treat
correlations between two and three consecutive spacings in the energy level
spectrum. These are generalizations of the Wigner surmise for the probability
distribution of single level spacing. The analytic formulae are shown to be in
good agreement with numerical evaluation.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:02:58 GMT"
},
{
"version": "v2",
"created": "Mon, 4 Feb 2008 21:40:52 GMT"
}
] | 2008-02-04T00:00:00 | [
[
"Herman",
"D.",
""
],
[
"Ong",
"T. T.",
""
],
[
"Usaj",
"Gonzalo",
""
],
[
"Mathur",
"H.",
""
],
[
"Baranger",
"H. U.",
""
]
] |
0707.1621 | Troels Harmark | Troels Harmark, Kristjan R. Kristjansson and Marta Orselli | Decoupling limits of N=4 super Yang-Mills on R x S^3 | 48 pages, 1 figure; added references, published version | JHEP 0709:115,2007 | 10.1088/1126-6708/2007/09/115 | null | hep-th | null | We find new decoupling limits of N=4 super Yang-Mills (SYM) on R x S^3 with
gauge group SU(N). These decoupling limits lead to decoupled theories that are
much simpler than the full N=4 SYM but still contain many of its interesting
features. The decoupling limits correspond to being in a near-critical region,
near a point with zero temperature and critical chemical potentials. The new
decoupling limits are found by generalizing the limits of hep-th/0605234 to
include not only the chemical potentials for the SU(4) R-symmetry of N=4 SYM
but also the chemical potentials corresponding to the SO(4) symmetry. In the
decoupled theories it is possible to take a strong coupling limit in a
controllable manner since the full effective Hamiltonian is known. For planar
N=4 SYM on R x S^3 all the decoupled theories correspond to fully integrable
spin chains. We study the thermodynamics of the decoupled theories and find the
Hagedorn temperature for small and large values of the effective coupling. We
find an alternative formulation of the decoupling limits in the microcanonical
ensemble. This leads to a characterization of certain regimes of weakly coupled
N=4 SYM in which there are string-like states. Finally, we find a similar
decoupling limit for pure Yang-Mills theory, which for the planar limit leads
to a fully integrable decoupled theory.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:53:12 GMT"
},
{
"version": "v2",
"created": "Fri, 28 Sep 2007 09:20:10 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Harmark",
"Troels",
""
],
[
"Kristjansson",
"Kristjan R.",
""
],
[
"Orselli",
"Marta",
""
]
] |
0707.1622 | Eran Bouchbinder | Eran Bouchbinder, Ting-Shek Lo and Itamar Procaccia | Dynamic Failure in Amorphous Solids via a Cavitation Instability | 4 pages, 4 figures | Phys. Rev. E 77, 025101(R) (2008) | 10.1103/PhysRevE.77.025101 | null | cond-mat.mtrl-sci cond-mat.dis-nn | null | The understanding of dynamic failure in amorphous materials via the
propagation of free boundaries like cracks and voids must go beyond elasticity
theory, since plasticity intervenes in a crucial and poorly understood manner
near the moving free boundary. In this Letter we focus on failure via a
cavitation instability in a radially-symmetric stressed material, set up the
free boundary dynamics taking both elasticity and visco-plasticity into
account, using the recently proposed athermal Shear Transformation Zone theory.
We demonstrate the existence (in amorphous systems) of fast cavitation modes
accompanied by extensive plastic deformations and discuss the revealed physics.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:53:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bouchbinder",
"Eran",
""
],
[
"Lo",
"Ting-Shek",
""
],
[
"Procaccia",
"Itamar",
""
]
] |
0707.1623 | Sumio Wada | Sumio Wada | Derivation of the Quantum Probability Rule without the Frequency
Operator | 12 pages | J.Phys.Soc.Jpn, Vol.76,094004(2007) | 10.1143/JPSJ.76.094004 | null | quant-ph | null | We present an alternative frequencists' proof of the quantum probability rule
which does not make use of the frequency operator, with expectation that this
can circumvent the recent criticism against the previous proofs which use it.
We also argue that avoiding the frequency operator is not only for technical
merits for doing so but is closely related to what quantum mechanics is all
about from the viewpoint of many-world interpretation.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 08:49:17 GMT"
}
] | 2007-10-01T00:00:00 | [
[
"Wada",
"Sumio",
""
]
] |
0707.1624 | Menachem Tsindlekht | M.E. Perel'man | Sound beyond the speed of light: destructive interference, anomalous
dispersion and nonlocality of near field | 5 pages | null | null | null | physics.class-ph physics.optics | null | Experimentally fixed sound pulse beyond of light speed in the region of
anomalous dispersion [W. M. Robertson, e. a. Appl. Phys. Lett, 90, 014102
(2007)] can be explained, as well as the similar superluminal phenomena, by
"the nonlocality in the small" of near electromagnetic field at transferring of
relevanted excitations.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:55:36 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Perel'man",
"M. E.",
""
]
] |
0707.1625 | Ilya Tipunin | G. Mutafyan, I. Yu. Tipunin | Double affine Hecke algebra in logarithmic conformal field theory | null | null | null | null | math.QA hep-th | null | We construct the representation of Double Affine Hecke Algebra whose
symmetrization gives the center of the quantum group U_q(sl(2)) and by
Kazhdan--Lusztig duality the Verlinde algebra of (1,p) models of logarithmic
conformal field theory.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 13:59:49 GMT"
}
] | 2007-07-16T00:00:00 | [
[
"Mutafyan",
"G.",
""
],
[
"Tipunin",
"I. Yu.",
""
]
] |
0707.1626 | Laurentiu Leustean | Ulrich Kohlenbach and Laurentiu Leustean | Asymptotically nonexpansive mappings in uniformly convex hyperbolic
spaces | to appear in Journal of the European Mathematical Society; minor
revision | null | null | null | math.FA math.LO | null | This paper provides a fixed point theorem for asymptotically nonexpansive
mappings in uniformly convex hyperbolic spaces as well as new effective results
on the Krasnoselski-Mann iterations of such mappings. The latter were found
using methods from logic and the paper continues a case study in the general
program of extracting effective data from prima-facie ineffective proofs in the
fixed point theory of such mappings.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:00:51 GMT"
},
{
"version": "v2",
"created": "Wed, 26 Mar 2008 16:52:17 GMT"
}
] | 2008-03-26T00:00:00 | [
[
"Kohlenbach",
"Ulrich",
""
],
[
"Leustean",
"Laurentiu",
""
]
] |
0707.1627 | Sang-Koog Kim | Dae-Eun Jeong and Sang-Koog Kim | Soft X-ray Circular Reflectivity from Ferromagnetic Transition-Metal
Films Near the Brewster's Angle: Theoretical and Numerical X-ray Resonant
Magnetic Scattering Study | 16 pages, 3 figures, 1 table | Phys Rev B 78, 012412 (2008) | 10.1103/PhysRevB.78.012412 | null | cond-mat.other | null | We first report a novel phenomenon that manifests itself in a colossal
difference in soft x-ray reflectivity from ferromagnetic transition-metal films
between the left- and right-handed circular polarization (LCP and RCP) modes at
a resonance near normal Brewster's angle. Theoretical and numerical studies of
sft x-ray resonant magnetic scattering using the circular-polarization-mode
basis reveal that this effect arises from a totally destructive interference of
photons scattered individually from chargem orbital, and spin degrees of
freedom in magnetized thin films that selectively occurs only for one helicity
of the opposite circular modes when the required criteria are fulfilled. Across
the normal Brewster's angle. the polarization state of scattered soft x-ray is
continuously variable from the RCP to the LCP mode (or vice versa) through the
linear s polarization mode by changing the incidence angle of linear
p-polarized x rays at the resonance.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:02:38 GMT"
}
] | 2010-02-03T00:00:00 | [
[
"Jeong",
"Dae-Eun",
""
],
[
"Kim",
"Sang-Koog",
""
]
] |
0707.1628 | Bernard Brighi | Mohamed A\"iboudi, Bernard Brighi (LMIA) | On the solutions of a boundary value problem arising in free convection
with prescribed heat flux | null | null | null | null | math.DS | null | For given $a\in\R$, c<0, we are concerned with the solution $f^{}_b$ of the
differential equation
$f^{\prime\prime\prime}+ff^{\prime\prime}+\g(f^{\prime})=0$, satisfying the
initial conditions $f(0)=a$, $f'(0)=b$, $f''(0)=c< 0$, where g is some
nonnegative subquadratic locally Lipschitz function. It is proven that there
exists $b_*>0$ such that $f^{}_b$ exists on $[0,+\infty)$ and is such that
$f'_b(t)\to 0$ as $t\to+\infty$, if and only if $b\geq b_*$. This allows to
answer questions about existence, uniqueness and boundedness of solutions to a
boundary value problem arising in fluid mechanics, and especially in boundary
layer theory.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:10:27 GMT"
}
] | 2007-07-12T00:00:00 | [
[
"Aïboudi",
"Mohamed",
"",
"LMIA"
],
[
"Brighi",
"Bernard",
"",
"LMIA"
]
] |
0707.1629 | Miled Moussa H Y | M. A. de Ponte, S. S. Mizrahi, and M. H. Y. Moussa | Storing quantum states in bosonic dissipative networks | null | null | 10.1088/0953-4075/41/21/215506 | null | quant-ph | null | Considering a network of dissipative quantum harmonic oscillators we deduce
and analyze the optimum topologies which are able to store, for the largest
period of time, a quantum superposition previously prepared in one of the
network oscillators. The storage of the superposition is made dynamically, in
that the state to be protected evolves through the network before being
retrieved back in the oscillator where it was prepared. The decoherence time
during the dynamic storage process is computed and we demonstrate that it is
proportional to the number of oscillators in the network for a particular
regime of parameters.
| [
{
"version": "v1",
"created": "Wed, 11 Jul 2007 14:28:18 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"de Ponte",
"M. A.",
""
],
[
"Mizrahi",
"S. S.",
""
],
[
"Moussa",
"M. H. Y.",
""
]
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.