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0704.0401
Modelling the Near-IR Spectra of Red Supergiant-dominated Populations
We report on recent progress in the modelling of the near-IR spectra of young stellar populations, i.e. populations in which red supergiants (RSGs) are dominant. First, we discuss the determination of fundamental parameters of RSGs using fits to their near-IR spectra with new PHOENIX model spectra; RSG-specific surfa...
astro-ph
0704.0402
Locating the peaks of least-energy solutions to a quasilinear elliptic Neumann problem
In this paper we study the shape of least-energy solutions to a singularly perturbed quasilinear problem with homogeneous Neumann boundary condition. We use an intrinsic variation method to show that at limit, the global maximum point of least-energy solutions goes to a point on the boundary faster than the linear ra...
math.AP
0704.0403
Review: Semiconductor Quantum Light Sources
Lasers and LEDs display a statistical distribution in the number of photons emitted in a given time interval. New applications exploiting the quantum properties of light require sources for which either individual photons, or pairs, are generated in a regulated stream. Here we review recent research on single-photon ...
quant-ph
0704.0404
To the origin of the difference of FSI phases in $B\to\pi\pi$ and $B\to\rho\rho$ decays
The final state interactions (FSI) model in which soft rescattering of low mass intermediate states dominates is suggested. It explains why the strong interaction phases are large in the $B_d\to\pi\pi$ channel and are considerably smaller in the $B_d\to\rho\rho$ one. Direct CP asymmetries of $B_d\to\pi\pi$ decays whi...
hep-ph hep-ex
0704.0405
An invariance principle for semimartingale reflecting Brownian motions in domains with piecewise smooth boundaries
Semimartingale reflecting Brownian motions (SRBMs) living in the closures of domains with piecewise smooth boundaries are of interest in applied probability because of their role as heavy traffic approximations for some stochastic networks. In this paper, assuming certain conditions on the domains and directions of r...
math.PR
0704.0406
Finite Drude weight for 1D low temperature conductors
We apply well established finite temperature Quantum Monte Carlo techniques to one dimensional Bose systems with soft and hardcore constraint, as well as to spinless fermion systems. We give clear and robust numerical evidence that, as expected, no superfluid density for Bosons or Meissner fraction for fermions. is p...
cond-mat.str-el cond-mat.supr-con
0704.0407
Density dependent hadronic models and the relation between neutron stars and neutron skin thickness
In the present work we investigate the main differences in the lead neutron skin thickness, binding energy, surface energy and density profiles obtained with two different density dependent relativistic hadronic models, within the Thomas-Fermi approximation. We show that the asymmetry parameter for low momentum trans...
nucl-th
0704.0408
Photoconductance of organic single-molecule contacts
We study the dc conductance of organic single-molecule contacts in the presence of external electromagnetic radiation (photoconductance). In agreement with previous predictions, we find that the radiation can lead to large enhancements of the conductance of such contacts by bringing off-resonant levels into resonance...
cond-mat.mes-hall
0704.0409
On the over-barrier reflection in quantum mechanics with multiple degrees of freedom
We present an analytic example of two dimensional quantum mechanical system, where the exponential suppression of the probability of over-barrier reflection changes non-monotonically with energy. The suppression is minimal at certain "optimal" energies where reflection occurs with exponentially larger probability tha...
quant-ph hep-th nlin.CD physics.atom-ph physics.chem-ph
0704.0410
Cyclotron Resonance study of the electron and hole velocity in graphene monolayers
We report studies of cyclotron resonance in monolayer graphene. Cyclotron resonance is detected using the photoconductive response of the sample for several different Landau level occupancies. The experiments measure an electron velocity at the K- (Dirac) point of $c_{K}^{*}$ = 1.093 x 10$^{6}$ ms$^{-1}$ and in addit...
cond-mat.mes-hall
0704.0411
Molecular circuits based on graphene nano-ribbon junctions
Graphene nano-ribbons junctions based electronic devices are proposed in this Letter. Non-equilibrium Green function calculations show that nano-ribbon junctions tailored from single layer graphene with different edge shape and width can act as metal-semiconductor junctions and quantum dots can be implemented. In vir...
cond-mat.mes-hall cond-mat.mtrl-sci
0704.0412
Unit groups of integral finite group rings with no noncyclic abelian finite subgroups
It is shown that in the units of augmentation one of an integral group ring $\mathbb{Z} G$ of a finite group $G$, a noncyclic subgroup of order $p^{2}$, for some odd prime $p$, exists only if such a subgroup exists in $G$. The corresponding statement for $p=2$ holds by the Brauer--Suzuki theorem, as recently observed...
math.RT math.RA
0704.0413
Exotic Hadron in Pole-dominated QCD Sum Rules
We study pentaquark $\Theta^{+} (I=0,J=1/2)$ in the QCD sum rules emphasizing that we can not extract any properties of the pentaquark outside of the Borel window. To find the appropriate Borel window, we prepare a favorable set up of the correlators and carry out the operator product expansion up to dimension 15 wit...
hep-ph
0704.0414
Leaky modes of a left-handed slab
Using complex plane analysis we show that left-handed slab may support either leaky slab waves, which are backward because of negative refraction, or leaky surface waves, which are backward or forward depending on the propagation direction of the surface wave itself. Moreover, there is a general connection between th...
physics.optics
0704.0415
Coulomb blockade of field emission from nanoscale conductors
Theoretical description of the field emission of electrons from nanoscale objects weakly coupled to the cathode is presented. It is shown that the field- emission current increases in a step-like fashion due to single-electron charging which leads to abrupt changes of the effective electric field responsible for the ...
cond-mat.mes-hall
0704.0416
Origamis with non congruence Veech groups
As main result we show that for each g > 1 there is some translation surface of genus g whose Veech group is a non congruence subgroup of SL(2,Z). We use origamis/square-tiled surfaces to produce our examples. The article is divided into two parts: In the first part we introduce translation surfaces, origamis, Veech ...
math.GT math.AG
0704.0417
Thermodynamic Stability - A note on a footnote in Ruelle's book
Thermodynamic stable interaction pair potentials which are not of the form ``positive function + real continuous function of positive type'' are presented in dimension one. Construction of such a potential in dimension two is sketched. These constructions use only elementary calculations. The mathematical background ...
math-ph math.MP
0704.0418
Entanglement entropy at infinite randomness fixed points in higher dimensions
The entanglement entropy of the two-dimensional random transverse Ising model is studied with a numerical implementation of the strong disorder renormalization group. The asymptotic behavior of the entropy per surface area diverges at, and only at, the quantum phase transition that is governed by an infinite randomne...
cond-mat.dis-nn quant-ph
0704.0419
Ultrasound attenuation of superfluid $^{3}$He in aerogel
We have performed longitudinal ultrasound (9.5 MHz) attenuation measurements in the B-phase of superfluid $^3$He in 98% porosity aerogel down to the zero temperature limit for a wide range of pressures at zero magnetic field. The absolute attenuation was determined by direct transmission of sound pulses. Compared to ...
cond-mat.supr-con
0704.0420
The Hourglass - Consequences of Pure Hamiltonian Evolution of a Radiating System
Hourglass is the name given here to a formal isolated quantum system that can radiate. Starting from a time when it defines the system it represents clearly and no radiation is present, it is given straightforward Hamiltonian evolution. The question of what significance hourglasses have is raised, and this question i...
quant-ph
0704.0421
The Sigma-D Relation for Planetary Nebulae: Preliminary Analysis
An analysis of the relation between radio surface brightness and diameter, so-called Sigma-D relation, for planetary nebulae (PNe) is presented: i) the theoretical Sigma-D relation for the evolution of bremsstrahlung surface brightness is derived; ii) contrary to the results obtained earlier for the Galactic supernov...
astro-ph
0704.0422
Polarization conversion in a silica microsphere
We experimentally demonstrate controlled polarization-selective phenomena in a whispering gallery mode resonator. We observed efficient ($\approx 75 %$) polarization conversion of light in a silica microsphere coupled to a tapered optical fiber with proper optimization of the polarization of the propagating light. A ...
physics.optics
0704.0423
Limits on WIMP-nucleon interactions with CsI(Tl) crystal detectors
The Korea Invisible Mass Search(KIMS) experiment presents new limits on WIMP-nucleon cross section using the data from an exposure of 3409 kgd taken with low background CsI(Tl) crystals at Yangyang underground laboratory. The most stringent limit on the spin dependent interaction for pure proton case is obtained. The...
astro-ph
0704.0424
Stopping effects in U+U collisions with a beam energy of 520 MeV/nucleon
A Relativistic Transport Model (ART1.0) is applied to simulate the stopping effects in tip-tip and body-body U+U collisions, at a beam kinetic energy of 520 MeV/nucleon. Our simulation results have demonstrated that both central collisions of the two extreme orientations can achieve full stopping, and also form a bul...
nucl-ex
0704.0425
QED for fields obeying a square root operator equation
Instead of using local field equations - like the Dirac equation for spin-1/2 and the Klein-Gordon equation for spin-0 particles - one could try to use non-local field equations in order to describe scattering processes. The latter equations can be obtained by means of the relativistic energy together with the corres...
hep-th
0704.0426
Feedback from first radiation sources: H- photodissociation
During the epoch of reionization, the formation of radiation sources is accompanied by the growth of a H- photodissociating flux. We estimate the impact of this flux on the formation of molecular hydrogen and cooling in the first galaxies, assuming different types of radiation sources (e.g. Pop II and Pop III stars, ...
astro-ph
0704.0427
The 3D +-J Ising model at the ferromagnetic transition line
We study the critical behavior of the three-dimensional $\pm J$ Ising model [with a random-exchange probability $P(J_{xy}) = p \delta(J_{xy} - J) + (1-p) \delta(J_{xy} + J)$] at the transition line between the paramagnetic and ferromagnetic phase, which extends from $p=1$ to a multicritical (Nishimori) point at $p=p_...
cond-mat.dis-nn cond-mat.stat-mech
0704.0428
Star Formation in the Bok Globule CB54
We present mid-infrared (10.4 \micron, 11.7 \micron, and 18.3 \micron) imaging intended to locate and characterize the suspected protostellar components within the Bok globule CB54. We detect and confirm the protostellar status for the near-infrared source CB54YC1-II. The mid-infrared luminosity for CB54YC1-II was fo...
astro-ph
0704.0429
Quantitative Resolution to some "Absolute Discrepancies" in Cancer Theories: a View from Phage lambda Genetic Switch
Is it possible to understand cancer? Or more specifically, is it possible to understand cancer from genetic side? There already many answers in literature. The most optimistic one has claimed that it is mission-possible. Duesberg and his colleagues reviewed the impressive amount of research results on cancer accumula...
q-bio.SC q-bio.CB
0704.0430
Reduced phase space and toric variety coordinatizations of Delzant spaces
In this note we describe the natural coordinatizations of a Delzant space defined as a reduced phase space (symplectic geometry view-point) and give explicit formulas for the coordinate transformations. For each fixed point of the torus action on the Delzant polytope, we have a maximal coordinatization of an open cel...
math.SG math.AG
0704.0431
Fragmentation of general relativistic quasi-toroidal polytropes
We investigate the role of rotational instabilities in the context of black hole formation in relativistic stars. In addition to the standard scenario - an axially symmetric dynamical instability forming a horizon at the star's center - the recently found low-$T/|W|$ instabilities are shown to lead to fragmentation a...
gr-qc astro-ph.HE
0704.0432
A Survey of Huebschmann and Stasheff's Paper: Formal Solution of the Master Equation via HPT and Deformation Theory
These notes, based on the paper "Formal Solution of the Master Equation via HPT and Deformation Theory" by Huebschmann and Stasheff, were prepared for a series of talks at Illinois State University with the intention of applying Homological Perturbation Theory to the derived bracket constructions of Kosmann-Schwarzba...
math.QA
0704.0433
A variational formulation of electrodynamics with external sources
We present a variational formulation of electrodynamics using de Rham even and odd differential forms. Our formulation relies on a variational principle more complete than the Hamilton principle and thus leads to field equations with external sources and permits the derivation of the constitutive relations. We interp...
math-ph math.DG math.MP
0704.0434
Protein and ionic surfactants - promoters and inhibitors of contact line pinning
We report a new effect of surfactants in pinning a drop contact line, specifically that lysozyme promotes while lauryl sulfate inhibits pinning. We explain the pinning disparity assuming difference in wetting: the protein-laden drop wets a "clean" surface and the surfactant-laden drop wets an auto-precursored surface...
physics.chem-ph physics.flu-dyn
0704.0435
Type D Einstein spacetimes in higher dimensions
We show that all static spacetimes in higher dimensions are of Weyl types G, I_i, D or O. This applies also to stationary spacetimes if additional conditions are fulfilled, as for most known black hole/ring solutions. (The conclusions change when the Killing generator becomes null, such as at Killing horizons.) Next ...
gr-qc hep-th
0704.0436
Eigen Equation of the Nonlinear Spinor
How to effectively solve the eigen solutions of the nonlinear spinor field equation coupling with some other interaction fields is important to understand the behavior of the elementary particles. In this paper, we derive a simplified form of the eigen equation of the nonlinear spinor, and then propose a scheme to so...
physics.gen-ph
0704.0437
Measurement of B(D_S^+ --> ell^+ nu) and the Decay Constant f_D_{S^+}
We examine e+e- --> Ds- Ds*+ and Ds*- Ds+ interactions at 4170 MeV using the CLEO-c detector in order to measure the decay constant fDs+. We use the Ds+ --> l+ nu channel, where the l+ designates either a mu+ or a tau+, when the tau+ --> pi+ nu. Analyzing both modes independently, we determine B(Ds+ --> mu+ nu) = (0....
hep-ex hep-lat hep-ph
0704.0438
Broadening the Higgs Boson with Right-Handed Neutrinos and a Higher Dimension Operator at the Electroweak Scale
The existence of certain TeV suppressed higher-dimension operators may open up new decay channels for the Higgs boson to decay into lighter right-handed neutrinos. These channels may dominate over all other channels if the Higgs boson is light. For a Higgs boson mass larger than $2 m_W$ the new decays are subdominant...
hep-ph
0704.0439
Coulomb blockade of anyons
Coulomb interaction turns anyonic quasiparticles of a primary quantum Hall liquid with filling factor $\nu =1/(2m+1)$ into hard-core anyons. We have developed a model of coherent transport of such quasiparticles in systems of multiple antidots by extending the Wigner-Jordan description of 1D abelian anyons to tunneli...
cond-mat.mes-hall
0704.0440
Dynamics of a quantum phase transition in a ferromagnetic Bose-Einstein condensate
We discuss dynamics of a slow quantum phase transition in a spin-1 Bose-Einstein condensate. We determine analytically the scaling properties of the system magnetization and verify them with numerical simulations in a one dimensional model.
cond-mat.other hep-th quant-ph
0704.0441
Evidence for a planetary companion around a nearby young star
We report evidence for a planetary companion around the nearby young star HD 70573. The star is a G type dwarf located at a distance of 46 pc with age estimation between 20 and 300 Myrs. We carried out spectroscopic observations of this star with FEROS at the 2.2 m MPG/ESO telescope at La Silla. Our spectroscopic ana...
astro-ph
0704.0442
Quantum electromagnetic X-waves
We show that two distinct quantum states of the electromagnetic field can be associated to a classical vector X wave or a propagation-invariant solution of Maxwell equations. The difference between the two states is of pure quantum mechanical origin since they are internally entangled and disentangled, respectively a...
physics.optics physics.gen-ph quant-ph
0704.0443
Neutron-neutron scattering length from the reaction gamma d --> pi^+ nn employing chiral perturbation theory
We discuss the possibility to extract the neutron-neutron scattering length a_{nn} from experimental spectra on the reaction gamma d --> pi^+ nn. The transition operator is calculated to high accuracy from chiral perturbation theory. We argue that for properly chosen kinematics, the theoretical uncertainty of the met...
nucl-th nucl-ex
0704.0444
Multiple Unfoldings of Orbifold Singularities: Engineering Geometric Analogies to Unification
Katz and Vafa showed how charged matter can arise geometrically by the deformation of ADE-type orbifold singularities in type IIa, M-theory, and F-theory compactifications. In this paper we use those same basic ingredients, used there to geometrically engineer specific matter representations, here to deform the compa...
hep-th
0704.0445
Geometrically Engineering the Standard Model: Locally Unfolding Three Families out of E8
This paper extends and builds upon the results of an earlier paper, in which we described how to use the tools of geometrical engineering to deform geometrically-engineered grand unified models into ones with lower symmetry. This top-down unfolding has the advantage that the relative positions of singularities giving...
hep-th
0704.0446
The classification of surfaces with p_g=q=1 isogenous to a product of curves
A projective surface S is said to be isogenous to a product if there exist two smooth curves C, F and a finite group G acting freely on C \times F so that S=(C \times F)/G. In this paper we classify all surfaces with p_g=q=1 which are isogenous to a product.
math.AG math.GR
0704.0447
Manipulating the rotational properties of a two-component Bose gas
A rotating, two-component Bose-Einstein condensate is shown to exhibit vortices of multiple quantization, which are possible due to the interatomic interactions between the two species. Also, persistent currents are absent in this system. Finally, the order parameter has a very simple structure for a range of angular...
cond-mat.mes-hall
0704.0448
Giant Planet Migration in Viscous Power-Law Discs
Many extra-solar planets discovered over the past decade are gas giants in tight orbits around their host stars. Due to the difficulties of forming these `hot Jupiters' in situ, they are generally assumed to have migrated to their present orbits through interactions with their nascent discs. In this paper, we present...
astro-ph
0704.0449
Worldsheet Instantons and Torsion Curves, Part B: Mirror Symmetry
We apply mirror symmetry to the problem of counting holomorphic rational curves in a Calabi-Yau threefold X with Z_3 x Z_3 Wilson lines. As we found in Part A [hep-th/0703182], the integral homology group H_2(X,Z)=Z^3 + Z_3 + Z_3 contains torsion curves. Using the B-model on the mirror of X as well as its covering sp...
hep-th
0704.0450
Disorder screening near the Mott-Anderson transition
Correlation-driven screening of disorder is studied within the typical-medium dynamical mean-field theory (TMT-DMFT) of the Mott-Anderson transition. In the strongly correlated regime, the site energies epsilon_R^i characterizing the effective disorder potential are strongly renormalized due to the phenomenon of Kond...
cond-mat.str-el
0704.0451
Electromigrated nanoscale gaps for surface-enhanced Raman spectroscopy
Single-molecule detection with chemical specificity is a powerful and much desired tool for biology, chemistry, physics, and sensing technologies. Surface-enhanced spectroscopies enable single molecule studies, yet reliable substrates of adequate sensitivity are in short supply. We present a simple, scaleable substra...
cond-mat.mes-hall
0704.0452
Dramatic Variability of X-ray Absorption Lines in the Black Hole Candidate Cygnus X-1
We report results from a 30 ks observation of Cygnus X-1 with the High Energy Transmission Grating Spectrometer (HETGS) on board the {\em Chandra X-ray Observatory}. Numerous absorption lines were detected in the HETGS spectrum. The lines are associated with highly ionized Ne, Na, Mg, Al, Si, S, and Fe, some of which...
astro-ph
0704.0453
Antiferromagnetism-superconductivity competition in electron-doped cuprates triggered by oxygen reduction
We have performed a systematic angle-resolved photoemission study of as-grown and oxygen-reduced Pr$_{2-x}$Ce$_x$CuO$_4$ and Pr$_{1-x}$LaCe$_{x}$CuO$_4$ electron-doped cuprates. In contrast to the common belief, neither the band filling nor the band parameters are significantly affected by the oxygen reduction proces...
cond-mat.supr-con cond-mat.str-el
0704.0454
An Extrasolar Planet Census with a Space-based Microlensing Survey
A space-based gravitational microlensing exoplanet survey will provide a statistical census of exoplanets with masses down to 0.1 Earth-masses and orbital separations ranging from 0.5AU to infinity. This includes analogs to all the Solar System's planets except for Mercury, as well as most types of planets predicted ...
astro-ph
0704.0455
USco1606-1935: An Unusually Wide Low-Mass Triple System?
We present photometric, astrometric, and spectroscopic observations of USco160611.9-193532 AB, a candidate ultrawide (~1600 AU), low-mass (M_tot~0.4 M_sun) multiple system in the nearby OB association Upper Scorpius. We conclude that both components are young, comoving members of the association; we also present high...
astro-ph
0704.0456
Particle propagation in cosmological backgrounds
We study the quantum propagation of particles in cosmological backgrounds, by considering a doublet of massive scalar fields propagating in an expanding universe, possibly filled with radiation. We focus on the dissipative effects related to the expansion rate. At first order, we recover the expected result that the ...
gr-qc
0704.0457
Quantum analysis of a linear DC SQUID mechanical displacement detector
We provide a quantum analysis of a DC SQUID mechanical displacement detector within the sub-critical Josephson current regime. A segment of the SQUID loop forms the mechanical resonator and motion of the latter is transduced inductively through changes in the flux threading the loop. Expressions are derived for the d...
cond-mat.supr-con cond-mat.mes-hall quant-ph
0704.0458
Rotation Measures of Extragalactic Sources Behind the Southern Galactic Plane: New Insights into the Large-Scale Magnetic Field of the Inner Milky Way
We present new Faraday rotation measures (RMs) for 148 extragalactic radio sources behind the southern Galactic plane (253o < l < 356o, |b| < 1.5o), and use these data in combination with published data to probe the large-scale structure of the Milky Way's magnetic field. We show that the magnitudes of these RMs osci...
astro-ph
0704.0459
On iterated image size for point-symmetric relations
Let $\Gamma =(V,E)$ be a point-symmetric reflexive relation and let $v\in V$ such that $|\Gamma (v)|$ is finite (and hence $|\Gamma (x)|$ is finite for all $x$, by the transitive action of the group of automorphisms). Let $j\in \N$ be an integer such that $\Gamma ^j(v)\cap \Gamma ^{-}(v)=\{v\}$. Our main result sta...
math.CO
0704.0460
The Kilodegree Extremely Little Telescope (KELT): A Small Robotic Telescope for Large-Area Synoptic Surveys
The Kilodegree Extremely Little Telescope (KELT) project is a survey for planetary transits of bright stars. It consists of a small-aperture, wide-field automated telescope located at Winer Observatory near Sonoita, Arizona. The telescope surveys a set of 26 x 26 degree fields, together covering about 25% of the Nort...
astro-ph
0704.0461
Entanglement increase from local interactions with not-completely-positive maps
Simple examples are constructed that show the entanglement of two qubits being both increased and decreased by interactions on just one of them. One of the two qubits interacts with a third qubit, a control, that is never entangled or correlated with either of the two entangled qubits and is never entangled, but beco...
quant-ph
0704.0462
Extended solar emission - an analysis of the EGRET data
The Sun was recently predicted to be an extended source of gamma-ray emission, produced by inverse-Compton scattering of cosmic-ray electrons with the solar radiation. The emission was predicted to contribute to the diffuse extragalactic background even at large angular distances from the Sun. While this emission is ...
astro-ph
0704.0463
Mass and Temperature of the TWA 7 Debris Disk
We present photometric detections of dust emission at 850 and 450 micron around the pre-main sequence M1 dwarf TWA 7 using the SCUBA camera on the James Clerk Maxwell Telescope. These data confirm the presence of a cold dust disk around TWA 7, a member of the TW Hydrae Association. Based on the 850 micron flux, we es...
astro-ph
0704.0464
Annealed importance sampling of dileucine peptide
Annealed importance sampling is a means to assign equilibrium weights to a nonequilibrium sample that was generated by a simulated annealing protocol. The weights may then be used to calculate equilibrium averages, and also serve as an ``adiabatic signature'' of the chosen cooling schedule. In this paper we demonstra...
q-bio.BM
0704.0465
A General Nonlinear Fokker-Planck Equation and its Associated Entropy
A recently introduced nonlinear Fokker-Planck equation, derived directly from a master equation, comes out as a very general tool to describe phenomenologically systems presenting complex behavior, like anomalous diffusion, in the presence of external forces. Such an equation is characterized by a nonlinear diffusion...
cond-mat.stat-mech cond-mat.other
0704.0466
Conduction electron spin-lattice relaxation time in the MgB2 superconductor
The spin-lattice relaxation time, $T_{1}$, of conduction electrons is measured as a function of temperature and magnetic field in MgB$_2$. The method is based on the detection of the $z$ component of the conduction electron magnetization under electron spin resonance conditions with amplitude modulated microwave exci...
cond-mat.supr-con cond-mat.str-el
0704.0467
Modeling Accretion Disk X-ray Continuum of Black Hole Candidates
We critically examine issues associated with determining the fundamental properties of the black hole and the surrounding accretion disk in an X-ray binary based on modeling the disk X-ray continuum of the source. We base our work mainly on two XMM-Newton observations of GX 339-4, because they provided high-quality d...
astro-ph
0704.0468
Inapproximability of Maximum Weighted Edge Biclique and Its Applications
Given a bipartite graph $G = (V_1,V_2,E)$ where edges take on {\it both} positive and negative weights from set $\mathcal{S}$, the {\it maximum weighted edge biclique} problem, or $\mathcal{S}$-MWEB for short, asks to find a bipartite subgraph whose sum of edge weights is maximized. This problem has various applicati...
cs.CC cs.DS
0704.0469
On line arrangements with applications to 3-nets
We show a one-to-one correspondence between arrangements of d lines in the projective plane, and lines in P^{d-2}. We apply this correspondence to classify (3,q)-nets over the complex numbers for all q<=6. When q=6, we have twelve possible combinatorial cases, but we prove that only nine of them are realizable. This ...
math.AG math.CO
0704.0470
Testing turbulence model at metric scales with mid-infrared VISIR images at the VLT
We probe turbulence structure from centimetric to metric scales by simultaneous imagery at mid-infrared and visible wavelengths at the VLT telescope and show that it departs significantly from the commonly used Kolmogorov model. The data can be fitted by the von Karman model with an outer scale of the order of 30 m a...
astro-ph
0704.0471
Density dependence of the symmetry energy and the nuclear equation of state: A Dynamical and Statistical model perspective
The density dependence of the symmetry energy in the equation of state of isospin asymmetric nuclear matter is of significant importance for studying the structure of systems as diverse as the neutron-rich nuclei and the neutron stars. A number of reactions using the dynamical and the statistical models of multifragm...
nucl-ex nucl-th
0704.0472
Competitive nucleation and the Ostwald rule in a generalized Potts model with multiple metastable phases
We introduce a simple nearest-neighbor spin model with multiple metastable phases, the number and decay pathways of which are explicitly controlled by the parameters of the system. With this model we can construct, for example, a system which evolves through an arbitrarily long succession of metastable phases. We als...
cond-mat.stat-mech cond-mat.mtrl-sci cond-mat.soft
0704.0473
Contrasting Two Transformation-Based Methods for Obtaining Absolute Extrema
In this note we contrast two transformation-based methods to deduce absolute extrema and the corresponding extremizers. Unlike variation-based methods, the transformation-based ones of Carlson and Leitmann and the recent one of Silva and Torres are direct in that they permit obtaining solutions by inspection.
math.OC
0704.0474
Application of Ewald summations to long-range dispersion forces
We present results illustrating the effects of using explicit summation terms for the $r^{-6}$ dispersion term on the interfacial properties of a Lennard-Jones fluid and SPC/E water. For the Lennard-Jones fluid, we find that the use of long-range summations, even with a short ``crossover radius,'' yields results that...
cond-mat.mtrl-sci cond-mat.stat-mech
0704.0475
Possible non-thermal nature of the soft-excess emission in the cluster of galaxies Sersic 159-03
We present an analysis of new Suzaku data and archival data from XMM-Newton of the cluster of galaxies Sersic 159-03, which has a strong soft X-ray excess emission component. The Suzaku observation confirms the presence of the soft excess emission, but it does not confirm the presence of redshifted OVII lines in the ...
astro-ph
0704.0476
Geometric phase of an atom inside an adiabatic radio frequency potential
We investigate the geometric phase of an atom inside an adiabatic radio frequency (rf) potential created from a static magnetic field (B-field) and a time dependent rf field. The spatial motion of the atomic center of mass is shown to give rise to a geometric phase, or Berry's phase, to the adiabatically evolving ato...
quant-ph
0704.0477
The Transition from the First Stars to the Second Stars in the Early Universe
We observe a sharp transition from a singular, high-mass mode of star formation, to a low-mass dominated mode, in numerical simulations, at a metallicity of 10^-3 Zsolar. We incorporate a new method for including the radiative cooling from metals into adaptive mesh-refinement hydrodynamic simulations. Our results ill...
astro-ph
0704.0478
Super Star Cluster Velocity Dispersions and Virial Masses in the M82 Nuclear Starburst
We use high-resolution near-infrared spectroscopy from Keck Observatory to measure the stellar velocity dispersions of 19 super star clusters (SSCs) in the nuclear starburst of M82. The clusters have ages on the order of 10 Myr, which is many times longer than the crossing times implied by their velocity dispersions ...
astro-ph
0704.0479
The affine part of the Picard scheme
We describe the maximal torus and maximal unipotent subgroup of the Picard variety of a proper scheme over a perfect field.
math.AG math.KT
0704.0480
Enhanced quantum Zeno effect and bunching in the decay of interacting bosons from an unstable state
paper withdrawn due to the possible error in numerical eigenfunction calculation
cond-mat.mes-hall
0704.0481
The few scales of nuclei and nuclear matter
The well-known correlations of low-energy three and four-nucleon observables with a typical three-nucleon scale (e.g., the Tjon line) is extended to light nuclei and nuclear matter. Evidence for the scaling between light nuclei binding energies and the triton one are pointed out. We argue that the saturation energy a...
nucl-th
0704.0482
Implementation of holonomic quantum computation through engineering and manipulating environment
We consider an atom-field coupled system, in which two pairs of four-level atoms are respectively driven by laser fields and trapped in two distant cavities that are connected by an optical fiber. First, we show that an effective squeezing reservoir can be engineered under appropriate conditions. Then, we show that a...
quant-ph
0704.0483
Vortex state in a Fulde-Ferrell-Larkin-Ovchinnikov superconductor based on the quasiclassical theory
We investigate the vortex state with Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) modulations suggested for a high field phase of CeCoIn_5. On the basis of the quasiclassical Eilenberger theory, we calculate the three dimensional structure of pair potentials, internal magnetic fields, paramagnetic moments, and electronic ...
cond-mat.supr-con
0704.0484
Search for Chaotic Behavior in a Flapping Flag
We measured the correlation of the times between successive flaps of a flag for a variety of wind speeds and found no evidence of low dimensional chaotic behavior in the return maps of these times. We instead observed what is best modeled as random times determined by an exponential distribution. This study was done ...
physics.ed-ph physics.gen-ph
0704.0485
Optimal Shape Design for Stokes Flow Via Minimax Differentiability
This paper is concerned with a shape sensitivity analysis of a viscous incompressible fluid driven by Stokes equations with nonhomogeneous boundary condition. The structure of shape gradient with respect to the shape of the variable domain for a given cost function is established by using the differentiability of a m...
math.OC
0704.0486
Kinematic Decoupling of Globular Clusters with Extended Horizontal-Branch
About 25% of the Milky Way globular clusters (GCs) exhibit unusually extended color distribution of stars in the horizontal-branch (HB) phase. This phenomenon is now best understood as due to the presence of helium enhanced second generation subpopulations, which has raised a possibility that these peculiar GCs might...
astro-ph
0704.0487
Scalar potential model progress
Because observations of galaxies and clusters have been found inconsistent with General Relativity (GR), the focus of effort in developing a Scalar Potential Model (SPM) has been on the examination of galaxies and clusters. The SPM has been found to be consistent with cluster cellular structure, the flow of IGM from ...
physics.gen-ph
0704.0488
Teleparallel Version of the Stationary Axisymmetric Solutions and their Energy Contents
This work contains the teleparallel version of the stationary axisymmetric solutions. We obtain the tetrad and the torsion fields representing these solutions. The tensor, vector and axial-vector parts of the torsion tensor are evaluated. It is found that the axial-vector has component only along $\rho$ and $z$ direc...
gr-qc
0704.0489
Relativistic treatment in D-dimensions to a spin-zero particle with noncentral equal scalar and vector ring-shaped Kratzer potential
The Klein-Gordon equation in D-dimensions for a recently proposed Kratzer potential plus ring-shaped potential is solved analytically by means of the conventional Nikiforov-Uvarov method. The exact energy bound-states and the corresponding wave functions of the Klein-Gordon are obtained in the presence of the noncent...
quant-ph
0704.0490
Long Distance Signaling Using Axion-like Particles
The possible existence of axion-like particles could lead to a new type of long distance communication. In this work, basic antenna concepts are defined and a Friis-like equation is derived to facilitate long-distance link calculations. An example calculation is presented showing that communication over distances of ...
hep-ph astro-ph hep-th
0704.0491
Weighted percolation on directed networks
We present an analysis of the percolation transition for general node removal strategies valid for locally tree-like directed networks. On the basis of heuristic arguments we predict that, if the probability of removing node $i$ is $p_i$, the network disintegrates if $p_i$ is such that the largest eigenvalue of the m...
cond-mat.soft cond-mat.dis-nn
0704.0492
Refuting the Pseudo Attack on the REESSE1+ Cryptosystem
We illustrate through example 1 and 2 that the condition at theorem 1 in [8] dissatisfies necessity, and the converse proposition of fact 1.1 in [8] does not hold, namely the condition Z/M - L/Ak < 1/(2 Ak^2) is not sufficient for f(i) + f(j) = f(k). Illuminate through an analysis and ex.3 that there is a logic error...
cs.CR
0704.0493
Phase structure of a surface model on dynamically triangulated spheres with elastic skeletons
We find three distinct phases; a tubular phase, a planar phase, and the spherical phase, in a triangulated fluid surface model. It is also found that these phases are separated by discontinuous transitions. The fluid surface model is investigated within the framework of the conventional curvature model by using the c...
cond-mat.stat-mech cond-mat.soft
0704.0494
Vortex Dynamics at the Initial Stage of Resistive Transition in Superconductors with Fractal Cluster Structure
The effect of fractal normal-phase clusters on vortex dynamics in a percolative superconductor is considered. The superconductor contains percolative superconducting cluster carrying a transport current and clusters of a normal phase, acting as pinning centers. A prototype of such a structure is YBCO film, containing...
cond-mat.supr-con cond-mat.mtrl-sci
0704.0495
The Veldkamp Space of Two-Qubits
Given a remarkable representation of the generalized Pauli operators of two-qubits in terms of the points of the generalized quadrangle of order two, W(2), it is shown that specific subsets of these operators can also be associated with the points and lines of the four-dimensional projective space over the Galois fie...
quant-ph math-ph math.MP
0704.0496
Fusion process studied with preequilibrium giant dipole resonance in time dependent Hartree-Fock theory
The equilibration of macroscopic degrees of freedom during the fusion of heavy nuclei, like the charge and the shape, are studied in the Time-Dependent Hartree-Fock theory. The pre-equilibrium Giant Dipole Resonance (GDR) is used to probe the fusion path. It is shown that such isovector collective state is excited in...
nucl-th
0704.0497
Penalization approach for mixed hyperbolic systems with constant coefficients satisfying a Uniform Lopatinski Condition
In this paper, we describe a new, systematic and explicit way of approximating solutions of mixed hyperbolic systems with constant coefficients satisfying a Uniform Lopatinski Condition via different Penalization approaches.
math.AP
0704.0498
A unified analysis of the reactor neutrino program towards the measurement of the theta_13 mixing angle
We present in this article a detailed quantitative discussion of the measurement of the leptonic mixing angle theta_13 through currently scheduled reactor neutrino oscillation experiments. We thus focus on Double Chooz (Phase I & II), Daya Bay (Phase I & II) and RENO experiments. We perform a unified analysis, includ...
hep-ex
0704.0499
Optimal Routing for Decode-and-Forward based Cooperation in Wireless Networks
We investigate cooperative wireless relay networks in which the nodes can help each other in data transmission. We study different coding strategies in the single-source single-destination network with many relay nodes. Given the myriad of ways in which nodes can cooperate, there is a natural routing problem, i.e., d...
cs.IT math.IT
0704.0500
On the polynomial automorphisms of a group
We prove that if a group is nilpotent (resp. metabelian), then so is the subgroup of its automorphism group generated by all polynomial automorphisms.
math.GR