October 2008 arXiv papers — page 4
Showing 301–400 of 5,765 papers
Stability of the vanishing of the $\overline\partial_b$-cohomology under small horizontal perturbations of the CR structure in compact abstract q-concave CR manifolds
math.CVChristine Laurent-Thiébaut
We consider perturbations of CR structures which preserve the complex tangent bundle. For a compact generic CR manifold its concavity properties and hence the finiteness of some $\overline\partial_b$-cohomology groups are also preserved by such perturbations of the CR structure. Here we study the stability of the vanishing of these groups.
Effect of Sm-, Gd- codoping on structural modifications in aluminoborosilicate glasses under beta-irradiation
cond-mat.mtrl-sciEvguenia Malchukova, Bruno Boizot, Guillaume Petite, Dominique Ghaleb
Two series of Sm-, Gd-codoped aluminoborosilicate glasses with different total rare earth content have been studied in order to examine the codoping effect on the structural modifications of beta-irradiated glasses. The data obtained by Electron Paramagnetic Resonance spectroscopy indicated that relative amount of Gd3+ ions located in network former position
Jeffrey Boerner
We construct an infinite family of homology theories of framed links in thickened surfaces, as well as a homology theory whose graded Euler characteristic is exactly the Kauffman bracket of the link in the surface. Both theories are based on ideas coming from Asaeda, Przytycki and Sikora's categorification of the Kauffman bracket skein module of I-bundle
Omar El-Dakkak
In this paper, we obtain some uniform laws of large numbers and functional central limit theorems for sequential empirical measure processes indexed by classes of product functions satisfying appropriate Vapnik-Chervonenkis properties.
Didier Clamond
A robust, fast and accurate method for solving the Colebrook-like equations is presented. The algorithm is efficient for the whole range of parameters involved in the Colebrook equation. The computations are not more demanding than simplified approximations, but they are much more accurate. The algorithm is also faster and more robust than the Colebrook solu
Sophie Morier-Genoud, Valentin Ovsienko
We show that the classical algebra of quaternions is a commutative $\Z_2\times\Z_2\times\Z_2$-graded algebra. A similar interpretation of the algebra of octonions is impossible.
Sloane J. Wiktorowicz, Keith Matthews
We present commissioning data for the POLISH instrument obtained on the Hale 5-m telescope. The goal of this high precision polarimeter is to constrain orbital inclination of high mass X-ray binaries and to therefore obtain independent mass estimates for their black hole companions. We have obtained photon shot noise limited precision on standard stars, and
Pat Scott, Malcolm Fairbairn, Joakim Edsjö
The presence of large amounts of WIMP dark matter in stellar cores has been shown to have significant effects upon models of stellar evolution. We present a series of detailed grids of WIMP-influenced stellar models for main sequence stars, computed using the DarkStars code. We describe the changes in stellar structure and main sequence evolution which occur
Vladlen Timorin
Regluing is a topological operation that helps to construct topological models for rational functions on the boundaries of certain hyperbolic components. It also has a holomorphic interpretation, with the flavor of infinite dimensional Thurston--Teichm\"uller theory. We will discuss a topological theory of regluing, and trace a direction in which a holomorph
A spectroscopic survey of dwarf galaxies in the Coma Cluster: Stellar populations, environment and downsizing
astro-phRussell J. Smith, John R. Lucey, Michael J. Hudson, Steven P. Allanson
We investigate the stellar populations in a sample of 89 faint (M*+2 to M*+4) red galaxies in the Coma cluster, using high S/N spectroscopy from the MMT. Our sample is drawn from two 1-degree fields, one centred on the cluster core and the other located a degree to the south west of the cluster centre. For a comparison sample we use published high-S/N data f
V. Luridiana, S. Simon-Diaz, M. Cervino, R. Gonzalez Delgado
(abridged) Non-ionizing stellar continua are a source of photons for continuum pumping in the hydrogen Lyman transitions. In the environments where these transitions are optically thick, deexcitation occurs through higher series lines, so that the flux in these lines has a fluorescent contribution in addition to recombination; in particular, Balmer emissivit
G. Ghisellini, F. Tavecchio, G. Bodo, A. Celotti
Recent Cerenkov observations of the two BL Lac objects PKS 2155-304 and Mkn 501 revealed TeV flux variability by a factor ~2 in just 3-5 minutes. Even accounting for the effects of relativistic beaming, such short timescales are challenging simple and conventional emitting models, and call for alternative ideas. We explore the possibility that extremely fast
LISA detection of massive black hole binaries: imprint of seed populations and of exterme recoils
astro-phA. Sesana, M. Volonteri, F. Haardt
All the physical processes involved in the formation, merging, and accretion history of massive black holes along the hierarchical build--up of cosmic structures are likely to leave an imprint on the gravitational waves detectable by future space--borne missions, such as LISA. We report here the results of recent studies, carried out by means of dedicated si
Sergio Iguri
A generalization of Selberg's beta integral involving Schur polynomials associated with partitions with entries not greater than 2 is explicitly computed. The complex version of this integral is given after proving a general statement concerning the complex extensions of Selberg-Schur integrals. All these results have interesting applications in both mat
Saul D. Cohen, Huey-Wen Lin, Jozef Dudek, Robert G. Edwards
We present a study of two-photon decays of light mesons, focusing on the neutral pion decay. This important process highlights the effects of the axial anomaly in QCD but has been little studied on the lattice. By applying the Lehmann-Symanzik-Zimmermann (LSZ) reduction formula, we reconstruct the electromagnetic matrix elements from three-point vector-vecto
Kaushik Choudhury, Joseph Thomas Andrews, Pranay Kumar Sen, Pratima Sen
Forces on a nanoparticle in an optical trap are analysed. Brownian motion is found to be one of the major challenges to trap a nanoparticle. Accordingly, suitable spatial electric field distribution of laser beam is suggested to enhance the trapping force on a nanoparticle. Theoretical analysis is carried out to obtain conditions for stable optical trap by i
Andreas Glatz, I. S. Beloborodov
We investigate thermopower and thermoelectric coefficient of nano-granular materials at large tunneling conductance between the grains, g_{T} >> 1. We show that at intermediate temperatures, T >= g_{T}δ, where δis the mean energy level spacing for a single grain, electron-electron interaction leads to an increase of the thermopower with decreasing grain size
Geraldo Botelho, Pablo Galindo, Leonardo Pellegrini
For each ideal of multilinear mappings $\cal M$ we explicitly construct a corresponding ideal $^{a}{\cal M}$ such that multilinear forms in $^{a}{\cal M}$ are exactly those which can be approximated, in the uniform norm, by multilinear forms in ${\cal M}$. This construction is then applied to finite type, compact, weakly compact and absolutely summing multil
Jean-Noël Aqua, Michael E. Fisher
To enable the study of criticality in multicomponent fluids, the standard spherical model is generalized to describe an $\ns$-species hard core lattice gas. On introducing $\ns$ spherical constraints, the free energy may be expressed generally in terms of an $\ns\times\ns$ matrix describing the species interactions. For binary systems, thermodynamic properti
Matias I. Jones
We used early time photometry and spectroscopy of 12 Type II plateau Supernovae (SNe IIP) to derive their distances using the Expanding Photosphere Method (EPM). We performed this study using two sets of Type II supernovae (SNe II) atmosphere models (E96, D05), three filter subsets (BV, BVI, VI) and two methods for the host galaxy extinctions, which led to 1
Benedetta Noris, Hugo Tavares, Susanna Terracini, Gianmaria Verzini
For the positive solutions of the competitive Gross-Pitaevskii system of two equations, we prove that L^\infty boundedness implies uniform Hölder boundedness as the competition parameter goes to infinity. Moreover we prove that the limiting profile is Lipschitz continuous. The proof relies upon the blow-up technique and the monotonicity formulae by Almgren a
Henryk Borowczyk
A new combinatorial-probabilistic diagnostic entropy has been introduced. It describes the pair-wise sum of probabilities of system conditions that have to be distinguished during the diagnosing process. The proposed measure describes the uncertainty of the system conditions, and at the same time complexity of the diagnosis problem. Treating the assumed comb
Roy van Boekel
This contribution reviews results from interferometric observations of circumstellar disks around young stars of $\lesssim$3 M$_{\odot}$, performed with the MIDI instrument operating in the 10 $μ$m spectral region. Two main topics, the disk structure on $\sim$1-10 AU scales and the dust properties in the same region, are illustrated with several examples of
Multilayer Adsorption of Polyatomic Species on Homogeneous and Heterogeneous Surfaces
cond-mat.mtrl-sciF. O. Sanchez-Varretti, G. D. Garcia, A. J. Ramirez-Pastor, F. Roma
In this work we study the multilayer adsorption of polyatomic species on homogeneous and heterogeneous bivariate surfaces. A new approximate analytic isotherm is obtained and validated by comparing with Monte Carlo simulation. Then, we use the well-known Brunauer-Emmet-Teller's (BET) approach to analyze these isotherms and to estimate the monolayer volum
Michael McDonald, Stephane Courteau, R. Brent Tully
We present bulge and disk (B/D) decompositions of existing K'-band surface brightness profiles for 65 Ursa Major cluster spiral galaxies. This improves upon the disk-only fits of Tully et al. (1996). The 1996 disk fits were used by Tully & Verheijen (1997) for their discovery of the bimodality of structural parameters in the UMa cluster galaxies. It is s
Ulrich W. Heinz
The Relativistic Heavy Ion Collider (RHIC) was built to re-create and study in the laboratory the extremely hot and dense matter that filled our entire universe during its first few microseconds. Its operation since June 2000 has been extremely successful, and the four large RHIC experiments have produced an impressive body of data which indeed provide compe
C. M. Copperwheat, T. R. Marsh, V. S. Dhillon, S. P. Littlefair
In this paper we present high time-resolution observations of GW Librae and SDSS J161033.64-010223.3 -- two cataclysmic variables which have shown periodic variations attributed to non-radial pulsations of the white dwarf. We observed both these systems in their quiescent states and detect the strong pulsations modes reported by previous authors. The identif
Marina Nielsen
I discuss some recent discoveries in the spectroscopy of the charmonium-like resonances, and some of their theoretical interpretations are reviewed.
Denis P. Ilyutko, Vassily O. Manturov
The present paper is an introduction to a combinatorial theory arising as a natural generalisation of classical and virtual knot theory. There is a way to encode links by a class of `realisable' graphs. When passing to generic graphs with the same equivalence relations we get `graph-links'. On one hand graph-links generalise the notion of virtual lin
M. S. Paoletti, Michael E. Fisher, D. P. Lathrop
By analyzing trajectories of solid hydrogen tracers in superfluid $^4$He, we identify tens of thousands of individual reconnection events between quantized vortices. We characterize the dynamics by the minimum separation distance $δ(t)$ between the two reconnecting vortices both before and after the events. Applying dimensional arguments, this separation has
Jonathan Browder
Let $sigma$ be a complete simplicial fan in finite dimensional real Euclidean space $V$, and let $G$ be a cyclic subgroup of $GL(V)$ which acts properly on $σ$. We show that the representation of $G$ carried by the cohomology of $X_{sigma}$, the toric variety associated to $sigma$, is a permutation representation.
Meservey-Tedrow-Fulde effect in a quantum dot embedded between metallic and superconducting electrodes
cond-mat.supr-conT. Domanski, A. Donabidowicz, K. I. Wysokinski
Magnetic field applied to the quantum dot coupled between one metallic and one superconducting electrode can produce a similar effect as has been experimentally observed by Meservey, Tedrow and Fulde [Phys. Rev. Lett. 25, 1270 (1970)] for the planar normal metal -- superconductor junctions. We investigate the tunneling current and show that indeed the square
Felipe Olivares
In this thesis we study the "standardized candle method" using a sample of 37 nearby (redshift < 0.06) Type II-plateau supernovae with BVRI photometry and optical spectroscopy. An analytic procedure is implemented to fit light, color, and velocity curves. We find that the V-I color toward the end of the plateau can be used to estimate host-galaxy red
Wilmari Bekker, Valentin Goranko
We introduce the class of rational Kripke models and study symbolic model checking of the basic tense logic Kt and some extensions of it in models from that class. Rational Kripke models are based on (generally infinite) rational graphs, with vertices labeled by the words in some regular language and transitions recognized by asynchronous two-head finite aut
Probing the Improbable: Methodological Challenges for Risks with Low Probabilities and High Stakes
physics.soc-phToby Ord, Rafaela Hillerbrand, Anders Sandberg
Some risks have extremely high stakes. For example, a worldwide pandemic or asteroid impact could potentially kill more than a billion people. Comfortingly, scientific calculations often put very low probabilities on the occurrence of such catastrophes. In this paper, we argue that there are important new methodological problems which arise when assessing gl
Maksim Kitsak, Massimo Riccaboni, Shlomo Havlin, Fabio Pammolli
We study the structure of business firm networks and scale-free models with degree distribution $P(q) \propto (q+c)^{-λ}$ using the method of $k$-shell decomposition.We find that the Life Sciences industry network consist of three components: a ``nucleus,'' which is a small well connected subgraph, ``tendrils,'' which are small subgraphs cons
C. Ryan Vinroot
We prove that Alvis-Curtis duality preserves the Frobenius-Schur indicators of characters of connected reductive groups of Lie type with connected center. This allows us to extend a result of D. Prasad which relates the Frobenius-Schur indicator of a regular real-valued character to its central character. We apply these results to compute the Frobenius-Schur
Terrence Draper, Takumi Doi, Keh-Fei Liu, Devdatta Mankame
We study the a_0 and K_0^* light scalar mesons in 2+1 flavor full QCD. Particular attention is paid to fitting excited states, with an eye toward determining whether scattering states are revealed. An ultimate goal will be to see how dynamical quarks affect the picture outlined with an earlier quenched study using overlap fermions, namely, that it is the a_0
Kaon condensation in the color-flavor-locked phase of quark matter, the Goldstone theorem, and the 2PI Hartree approximation
hep-phJens O. Andersen, Lars E. Leganger
At very high densities, QCD is in the color-flavor locked phase, which is a color-superconducting phase. The diquark condensates break chiral symmetry in the same way as it is broken in vacuum QCD and gives rise to an octet of pseudo-Goldstone bosons and a superfluid mode. The lightest of these are the charged and neutral kaons. For energies below the superc
Duccio Fanelli, Alan J. McKane
We describe the growth of vesicles, due to the accretion of lipid molecules to their surface, in terms of linear irreversible thermodynamics. Our treatment differs from those previously put forward by consistently including the energy of the membrane in the thermodynamic description. We calculate the critical radius at which the spherical vesicle becomes uns
Yaroslav V. Kartashov, Boris A. Malomed, Victor A. Vysloukh, Lluis Torner
We introduce a new species of gap solitons (GSs) supported by an azimuthally modulated guiding ring in defocusing cubic media. The periodicity in the azimuthal direction strongly modifies properties and existence domains of GSs. In addition to the fundamental solitons, we report even and twisted bound states. The former type is found to be stable, while the
Timoteo Carletti, Duccio Fanelli
We here discuss the outcome of an hypothetic experiments of populations dynamics, where a set of independent realizations is made available. The importance of ensemble average is clarified with reference to the registered time evolution of key collective indicators. The problem is here tackled for the logistic case study. Theoretical prediction are compared
Hannes-Sebastian Zechlin, Dieter Horns, Javier Redondo
Extensions of the standard model of particle physics, in particular those based on string theory, often predict a new U(1) gauge symmetry in a hidden sector. The corresponding gauge boson, called hidden photon, naturally interacts with the ordinary photon via gauge kinetic mixing, leading to photon - hidden photon oscillations. In this framework, one expects
Wolfgang Lucha
The most popular 3-dimensional reduction of the Bethe-Salpeter formalism for the description of bound states within quantum field theory is the Salpeter equation, found as the instantaneous limit of the Bethe-Salpeter framework if allowing, in addition, for free propagation of the bound-state constituents. Unfortunately, depending on the Lorentz nature of th
S. Temporin, P. -A. Duc, O. Ilbert, the XMM-LSS/SWIRE Collaboration
We present an investigation of the dust-enshrouded activity in a sample of X-ray selected clusters drawn from the XMM-LSS survey in the redshift range z ~ 0.05 - 1.05. By taking advantage of the contiguous mid-IR coverage of the XMM-LSS field by the Spitzer SWIRE legacy survey, we examined the distribution and number density of mid-IR bright sources out to t
Yves Gallot, Pieter Moree
A cyclotomic polynomial Phi_n(x) is said to be ternary if n=pqr with p,q and r distinct odd prime factors. Ternary cyclotomic polynomials are the simplest ones for which the behaviour of the coefficients is not completely understood. Eli Leher showed in 2007 that neighboring ternary cyclotomic coefficients differ by at most four. We show that, in fact, they
A problem in the Kourovka notebook concerning the number of conjugacy classes of a finite group
math.GRColin Reid
In this paper, we consider Problem 14.44 in the Kourovka notebook, which is a conjecture about the number of conjugacy classes of a finite group. While elementary, this conjecture is still open and appears to elude any straightforward proof, even in the soluble case. However, we do prove that a minimal soluble counterexample must have certain properties, in
Seok-Jin Kang, Masaki Kashiwara, Olivier Schiffmann
We provide a geometric realization of the crystal $B(\infty)$ for quantum generalized Kac-Moody algebras in terms of the irreducible components of certain Lagrangian subvarieties in the representation spaces of a quiver.
Andre C. Barato, Haye Hinrichsen
We consider a nonequilibrium process on a timeline with discrete sites which evolves by a non-Markovian update rule in such a way that an active site at time t activates one or several sites in the future at time t+dt. The time intervals dt are distributed algebraically as dt^(-1-kappa), where 0<kappa<1 is a control paramter. Depending on the activation rate
A. N. W. Hone, M. Petrera
Recently Hirota and Kimura presented a new discretization of the Euler top with several remarkable properties. In particular this discretization shares with the original continuous system the feature that it is an algebraically completely integrable bi-Hamiltonian system in three dimensions. The Hirota-Kimura discretization scheme turns out to be equivalent
S. Blanes, F. Casas, J. A. Oteo, J. Ros
Approximate resolution of linear systems of differential equations with varying coefficients is a recurrent problem shared by a number of scientific and engineering areas, ranging from Quantum Mechanics to Control Theory. When formulated in operator or matrix form, the Magnus expansion furnishes an elegant setting to built up approximate exponential represen
Eric Rosen
We prove a differential analog of a theorem of Chevalley on extending homomorphisms for rings with commuting derivations, generalizing a theorem of Kac. As a corollary, we establish that, under suitable hypotheses, the image of a differential scheme under a finite morphism is a constructible set. We also obtain a new algebraic characterization of differentia
L. Quiroga, C. Tejedor
We study in detail the generation and relaxation of quantum coherences (entanglement) in a system of coupled polariton traps. By exploiting a Lie algebraic based super-operator technique we provide an analytical exact solution for the Markovian dissipative dynamics (Master equation) of such system which is valid for arbitrary cluster size, polariton-polarito
Qiang Li, Yan He, Jing-ping Jiang
We introduce a modified model of random walk, and then develop two novel clustering algorithms based on it. In the algorithms, each data point in a dataset is considered as a particle which can move at random in space according to the preset rules in the modified model. Further, this data point may be also viewed as a local control subsystem, in which the co
Maarten Baes
Cosmological simulations suggest that dark matter haloes are not spherical, but typically moderately to strongly triaxial systems. We investigate methods to convert spherical potential-density pairs into axisymmetric ones, in which the basic characteristics of the density profile (such as the slope at small and large radii) are retained. We achieve this goal
Adrien Richard
We consider a boolean network whose interaction graph has no circuit of length >1. Under this hypothesis, we establish an upper bound on the length of the attractors of the network which only depends on its interaction graph.
E. Schwamberger, R. Vogt
Numerably contractible spaces play an important role in the theory of homotopy pushouts and pullbacks. The corresponding results imply that a number of well known weak homotopy equivalences are genuine ones if numerably contractible spaces are involved. In this paper we give a first systematic investigation of numerably contractible spaces. We list the eleme
B. G. Sidharth
In this paper we argue that it is possible to model the Universe along thermodynamic lines, using oscillators in the background Dark Energy at the Planck scale. This leads to meaningful results in agreement with observation.
Andrew Twigg
We give a simple algorithm for decremental graph connectivity that handles edge deletions in worst-case time $O(k \log n)$ and connectivity queries in $O(\log k)$, where $k$ is the number of edges deleted so far, and uses worst-case space $O(m^2)$. We use this to give an algorithm for $k$-edge witness (``does the removal of a given set of $k$ edges disconnec
K. Doll, J. C. Schoen, M. Jansen
Possible crystalline modifications of chemical compounds at low temperatures correspond to local minima of the energy landscape. Determining these minima via simulated annealing is one method for the prediction of crystal structures, where the number of atoms per unit cell is the only information used. It is demonstrated that this method can be applied to co
Maurizio Falanga
The outbursts of low mass X-ray binaries are prolonged relative to those of dwarf nova cataclysmic variables as a consequence of X-ray irradiation of the disc. We show that the time-scale of the decay light curve and its luminosity at a characteristic time are linked to the radius of the accretion disc. Hence a good X-ray light curve permits two independent
David J. Nott, Robert J. Kohn, Mark Fielding
Model selection is an important activity in modern data analysis and the conventional Bayesian approach to this problem involves calculation of marginal likelihoods for different models, together with diagnostics which examine specific aspects of model fit. Calculating the marginal likelihood is a difficult computational problem. Our article proposes some ex
N. J. Nunes, D. J. Mulryne
Non-local equations of motion contain an infinite number of derivatives and commonly appear in a number of string theory models. We review how these equations can be rewritten in the form of a diffusion-like equation with non-linear boundary conditions. Moreover, we show that this equation can be solved as an initial value problem once a set of non-trivial i
INTEGRAL and XMM-Newton Spectroscopy of GX 339-4 During Hard/Soft Intermediate and High/Soft States in the 2007 Outburst
astro-phM. D. Caballero-Garcia, J. M. Miller, M. Diaz Trigo, E. Kuulkers
We present simultaneous XMM-Newton and INTEGRAL observations of the luminous black hole transient and relativistic jet source GX 339-4. GX 339-4 started an outburst on November of 2006 and our observations were undertaken from January to March of 2007. We triggered five INTEGRAL and three XMM-Newton target of Opportunity observations within this period. Our
A. Lambrecht, I. G. Pirozhenko
We investigate the Casimir force between two dissimilar plane mirrors the material properties of which are described by Drude or Lorentz models. We calculate analytically the short and long distance asymptote of the force and relate its behavior to the influence of interacting surface plasmons. In particular we discuss conditions under which Casimir repulsio
Taikan Suehara, Masahiro Oroku, Takashi Yamanaka, Hakutaro Yoda
We developed an electron beam size monitor for extremely small beam sizes. It uses a laser interference fringe for a scattering target with the electron beam. Our target performance is < 2 nm systematic error for 37 nm beam size and < 10% statistical error in a measurement using 90 electron bunches for 25 - 6000 nm beam size. A precise laser interference fri
Slow relaxation of magnetoresistance in doped p -GaAs/AlGaAs layers with partially filled upper Hubbard band
cond-mat.dis-nnN. V. Agrinskaya, V. I. Kozub, D. V. Shamshur, A. Shumilin
We observed slow relaxation of magnetoresistance in quantum well structures GaAs-AlGaAs with a selective doping of both wells and barrier regions which allowed partial filling of the upper Hubbard band. Such a behavior is explained as related to magnetic-field driven redistribution of the carriers between sites with different occupation numbers due to spin c
Christoph Walker
We consider the well-posedness of models involving age structure and non-linear diffusion. Such problems arise in the study of population dynamics. It is shown how diffusion and age boundary conditions can be treated that depend non-linearly and possibly non-locally on the density itself. The abstract approach is depicted with examples.
Erik Darpö
Vector products can be defined on spaces of dimensions 0, 1, 3 and 7 only, and their isomorphism types are determined entirely by their adherent symmetric bilinear forms. We present a short and elementary proof for this classical result.
L. Ducci, L. Sidoli, A. Paizis, S. Mereghetti
INTEGRAL monitoring of the Galactic Plane in the last 5 years revealed a new subclass of High Mass X-ray Binaries (HMXBs), the Supergiant Fast X-ray Transients (SFXTs). They display flares lasting from minutes to hours, with peak luminosity of 1E36-1E37 erg/s and a frequent long term flaring activity reaching an X-ray luminosity of 1E33-1E34 erg/s, as recent
Electron- and phonon transport in silicon nanowires: an atomistic approach to thermoelectric properties
cond-mat.mes-hallTroels Markussen, Antti-Pekka Jauho, Mads Brandbyge
We compute both electron- and phonon transmissions in thin disordered silicon nanowires. Our atomistic approach is based on tight-binding and empirical potential descriptions of the electronic and phononic systems, respectively. Surface disorder is modeled by including surface silicon vacancies. It is shown that the average phonon- and electron transmissions
D. J. Urminsky, D. C. Heggie
In this study we consider the relationship between the survival time and the Lyapunov time for 3-body systems. It is shown that the Sitnikov problem exhibits a two-part power law relationship as demonstrated previously for the general 3-body problem. Using an approximate Poincare map on an appropriate surface of section, we delineate escape regions in a doma
Slow Relaxation and Equilibrium Dynamics in a 2 D Coulomb Glass: Demonstration of Stretched Exponential Energy Correlations
cond-mat.otherM. Kirkengen, J. Bergli
We have simulated energy relaxation and equilibrium dynamics in Coulomb Glasses using the random energy lattice model. We show that in a temperature range where the Coulomb Gap is already well developed, (T=0.03-0.1) the system still relaxes to an equilibrium behavior within the simulation time scale. For all temperatures T, the relaxation is slower than exp
A. Kurkela
It is expected that incorporating the center symmetry in the conventional dimensionally reduced effective theory for high-temperature SU(N) Yang-Mills theory, EQCD, will considerably extend its applicability towards the deconfinement transition. The construction of such a center-symmetric effective theory for the case of two colors is reviewed and lattice si
Gonca L. Aki, Peter A. Markowich, Christof Sparber
We consider the three-dimensional semi-relativistic Hartree model for fast quantum mechanical particles moving in a self-consistent field. Under appropriate assumptions on the initial density matrix as a (fully) mixed quantum state we prove, using Wigner transformation techniques, that its classical limit yields the well known relativistic Vlasov-Poisson sys
Jaroslav Bielcik
The strong suppression of hadrons with high transverse momenta in central Au+Au collisions observed at RHIC is generally interpreted as a consequence of energy loss of energetic partons in the hot and dense matter before fragmenting. The study of heavy quark production tests our understanding of energy loss mechanisms. Heavy quarks were expected to lose less
J. M. Paredes, J. Marti, C. H. Ishwara-Chandra, J. R. Sanchez-Sutil
MGRO J2019+37 is an unidentified source of very high energy gamma-rays originally reported by the MILAGRO collaboration as the brightest TeV source in the Cygnus region. Despite the poor angular resolution of MILAGRO, this object seems to be most likely an extended source or, alternatively, a superposition of point-like TeV sources. In order to contribute to
L. Ducci, L. Sidoli, A. Paizis, S. Mereghetti
We performed a detailed study of the 2007 outburst of the 352s pulsar SAXJ2103.5+4545, a Be/X-ray transient observed by INTEGRAL, to study its spectral and temporal properties during the evolution of the outburst. SAXJ2103.5+4545 was observed with IBIS/ISGRI from 25 to 27 April 2007 and from 6 to 8 May 2007. The 20-100keV spectrum is well described by a brem
Hiroyuki Abe, Tetsutaro Higaki, Tatsuo Kobayashi, Kazutoshi Ohta
We study the duality cascade of softly broken supersymmetric theories. We investigate the renormalization group (RG) flow of SUSY breaking terms as well as supersymmetric couplings. It is found that the magnitudes of SUSY breaking terms are suppressed in most regimes of the RG flow through the duality cascade. At one stage of cascading, the gaugino mass of t
High resolution in z-direction: The simulation of disc-bulge-halo galaxies using the particle-mesh code SUPERBOX
astro-phR. Bien, A. Just, P. Berczik, I. Berentzen
SUPERBOX is known as a very efficient particle-mesh code with highly-resolving sub-grids. Nevertheless, the height of a typical galactic disc is small compared to the size of the whole system. Consequently, the numerical resolution in z-direction, i.e. vertically with respect to the plane of the disc, remains poor. Here, we present a new version of SUPERBOX
Temperature dependence investigation of dissipation processes in strongly anisotropic high-temperature superconductors of Bi-Pb-Sr-Ca-Cu-O system synthesized using solar energy
cond-mat.supr-conJ. G. Chigvinadze, J. V. Acrivos, S. M. Ashimov, D. D. Gulamova
The investigation of temperature dependence of damping and period of vibrations of HTSC superconductive cylinder of Bi-Pb-Sr-Ca-Cu-O system suspended by a thin elastic thread and performing axial-torsional vibrations in a magnetic field at temperatures above the critical one for the main phase Tc=107 K were carried out. It was observed some "chaos" t
Supersolid phases of hardcore bosons on the square lattice: Correlated hopping, next-nearest neighbor hopping and frustration
cond-mat.str-elF. Mila, J. Dorier, K. P. Schmidt
We discuss the appearance of supersolid phases for interacting hardcore bosons on the square lattice when, in addition to the standard nearest neighbor hopping and repulsion, correlated or next-nearest neighbor hopping is present. Having in mind dimer-based quantum magnets in a field described by effective bosonic models of this kind, we put special emphasis
Swift monitoring of Supergiant Fast X-ray Transients: the out-of-outburst behaviour and the flares from IGRJ17544-2916 and XTEJ1739-302
astro-phL. Sidoli, P. Romano, G. Cusumano, V. Mangano
Supergiant Fast X-ray Transients (SFXTs) are a sub-class of High Mass X-ray Binaries (HMXBs) associated with OB supergiant companions and displaying transient X-ray activity. This behaviour is quite surprising since HMXBs hosting supergiants were known to be persistent sources, until the INTEGRAL discoveries obtained by means of the monitoring of the Galacti
H. J. Trodahl, N. Klein, D. Damjanovic, N. Setter
A Raman scattering spectroscopy study is reported through all four phases of a (K0.5Na0.5)NbO3 crystal and ((K0.5Na0.5)1-xLix)NbO3 for x=0.02 and 0.03. The transitions among the ferroelectric phases in the Li-free crystal are homogeneous and strongly hysteretic, with no evidence of a mixed-phase region between the rhombohedral and orthorhombic phases. The Ra
Lior Bary-Soroker
We generalize the notion of a projective profinite group to a projective pair of a profinite group and a closed subgroup. We establish the connection with Pseudo Algebraically Closed (PAC) extensions of PAC fields: Let M be an algebraic extension of a PAC field K. Then M/K is PAC if and only if the corresponding pair of absolute Galois groups (Gal(M),Gal(K))
Peter Tröger
Since the very beginning of hardware development, computer processors were invented with ever-increasing clock frequencies and sophisticated in-build optimization strategies. Due to physical limitations, this 'free lunch' of speedup has come to an end. The following article gives a summary and bibliography for recent trends and challenges in CMP arch
N G Fytas, A Malakis
We investigate and contrast, via the Wang-Landau (WL) algorithm, the effects of quenched bond randomness on the self-averaging properties of two Ising spin models in 2d. The random bond version of the superantiferromagnetic (SAF) square model with nearest- and next-nearest-neighbor competing interactions and the corresponding version of the simple ferromagne
Anthony G. A. Brown
The Gaia mission is reviewed together with the expected contents of the final catalogue. It is then argued that the ultimate goal of Galactic structure studies with Gaia astrometry should be to build a dynamical model of our galaxy which is capable of explaining the contents of the Gaia catalogue. This will be possible only by comparing predicted catalogue d
B. Basu, P. Bandyopadhyay
We have shown that the non-Abelian spin-orbit gauge field strength of the Rashba and Dresselhaus interactions, when split into two Abelian field strengths, the Hamiltonian of the system can be re-expressed as a Landau level problem with a particular relation between the two coupling parameters. The quantum levels are created with up and down spins with oppos
Patrick Cattiaux, Arnaud Guillin, Liming Wu
We give by simple arguments sufficient conditions, so called Lyapunov conditions, for Talagrand's transportation information inequality and for the logarithmic Sobolev inequality. Those sufficient conditions work even in the case where the Bakry-Emery curvature is not lower bounded. Several new examples are provided.
Mihkail Roytberg, Anna Gambin, Laurent Noé, Slawomir Lasota
We apply the concept of subset seeds proposed in [1] to similarity search in protein sequences. The main question studied is the design of efficient seed alphabets to construct seeds with optimal sensitivity/selectivity trade-offs. We propose several different design methods and use them to construct several alphabets.We then perform an analysis of seeds bui
Degradation of organic compounds and production of activated species in Dielectric Barrier Discharges and Glidarc reactors
physics.plasm-phJean Marie Cormier, Olivier Aubry, Ahmed Khacef
Major sterilization mechanisms are related to atoms and radicals, charged parti-cles, excited molecules, ozone, and UV radiation. The ROS (Reactive Oxygen Species) are well known as evildoers. These species are easily created in ambient air and water and they live long enough to reach the cell and attack the organic matter. Test molecules conversion in dry a
Ahmed Khacef, Jean Marie Cormier, Jean Michel Pouvesle, Tiep Le Van
Results on the application of non thermal plasmas in two environmentally important fields: oxidative removal of VOC and NOx in excess of oxygen were presented. The synergetic application of a plasma-catalytic treatment of NOx in excess of oxygen is also described.
Martin Hairer
We study a model of two interacting Hamiltonian particles subject to a common potential in contact with two Langevin heat reservoirs: one at finite and one at infinite temperature. This is a toy model for 'extreme' non-equilibrium statistical mechanics. We provide a full picture of the long-time behaviour of such a system, including the existence / n
Laszlo Lempert
We consider a compact complex manifold $M$, and introduce the notion of two holomorphic Banach bundles $E,F$ over $M$ being compact perturbations of one another. Given two such bundles we show that if the cohomology groups $H^q(M,E)$ are finite dimensional then so are the cohomology groups $H^q(M,F)$; as well as a more precise result in the same spirit.
J. Näf, P. Jetzer, M. Sereno
We study the effect of a cosmological constant $Λ$ on the propagation and detection of gravitational waves. To this purpose we investigate the linearised Einstein's equations with terms up to linear order in $Λ$ in a de Sitter and an anti-de Sitter background spacetime. In this framework the cosmological term does not induce changes in the polarization s
Density of eigenvalues and its perturbation invariance in unitary ensembles of random matrices
math-phDang-Zheng Liu, Zheng-Dong Wang, Kui-Hua Yan
We generally study the density of eigenvalues in unitary ensembles of random matrices from the recurrence coefficients with regularly varying conditions for the orthogonal polynomials. First we calculate directly the moments of the density. Then, by studying some deformation of the moments, we get a family of differential equations of first order which the d
Huai-Xiang Huang, Ying Jiang, Guo-Hong Yang
By making use of renormalized mean-field theory, we investigate possible superconducting symmetries in the ground states of t1-t2-J1-J2 model on square lattice. The superconducting symmetries of the ground states are determined by the frustration amplitude t2/t1 and doping concentration. The phase diagram of this system in frustration-doping plane is given.
Properties of Discrete Analogue of the Differential Operator $\frac{d^{2m}}{dx^{2m}}-\frac{d^{2m-2}}{dx^{2m-2}}$
math.NAKh. M. Shadimetov, A. R. Hayotov
In the paper properties of the discrete analogue $D_m(hβ)$ of the differential operator $\frac{d^{2m}}{dx^{2m}}-\frac{d^{2m-2}}{dx^{2m-2}}$ are studied. It is known, that zeros of differential operator $\frac{d^{2m}}{dx^{2m}}-\frac{d^{2m-2}}{dx^{2m-2}}$ are functions $e^x$, $e^{-x}$ and $P_{2m-3}(x)$. It is proved that discrete analogue $D_m(hβ)$ of this dif
Complex extension of potentials and trajectories of poles of the S-matrix element in the complex momentum plane
quant-phM. Kawasaki, T. Maehara, M. Yonezawa
Searching for infrastructure of the quantum mechanical system, we study trajectories of the s-wave poles of the S-matrix element with respect to a real phase $α$ in the complex momentum plane for a complex extension of real potentials by a phase factor $e^{iα}$. This complex extension relates the pole spectrum of the physical system with a potential to the s