July 2009 arXiv papers — page 43

V. Cirigliano, G. Ecker, A. Pich

We re-investigate the impact of isospin violation for extracting the s-wave pion pion scattering phase shift difference delta_0(M_K) - delta_2(M_K) from K -> pi pi decays. Compared to our previous analysis in 2003, more precise experimental data and improved knowledge of low-energy constants are used. In addition, we employ a more robust data-driven method t

Bjoern H. Wellegehausen, Andreas Wipf, Christian Wozar

Based on the strong coupling expansion we obtain effective 3-dimensional models for the Polyakov loop in finite-temperature G_2 gluodynamics. The Svetitsky-Jaffe conjecture relates the resulting continuous spin models with G_2 gluodynamics near phase transition points. In the present work we analyse the effective theory in leading order with the help of a ge

Yveline Lebreton, Josefina Montalban, Melanie Godart, Pierre Morel

Saio et al. (2006) have shown that the presence of an intermediate convective zone (ICZ) in post-main sequence models could prevent the propagation of g-modes in the radiative interior and hence avoid the corresponding radiative damping. The development of such a convective region highly depends on the structure of the star in the mu-gradient region surround

Matt J. Jarvis, Hanifa Teimourian, Chris Simpson, Daniel J. B. Smith

In this letter we report the discovery of a z=4.88 radio galaxy discovered with a new technique which does not rely on pre-selection of a sample based on radio properties such as steep-spectral index or small angular size. This radio galaxy was discovered in the Elais-N2 field and has a spectral index of alpha = 0.75, i.e. not ultra-steep spectrum. It also h

D. Spirkoska, J. Arbiol, A. Gustafsson, S. Conesa-Boj

The structural and optical properties of 3 different kinds of GaAs nanowires with 100% zinc-blende structure and with an average of 30% and 70% wurtzite are presented. A variety of shorter and longer segments of zinc-blende or wurtzite crystal phases are observed by transmission electron microscopy in the nanowires. Sharp photoluminescence lines are observed

D. Jack, P. H. Hauschildt, E. Baron

Aims. We present first results and tests of a time-dependent extension to the general purpose model atmosphere code PHOENIX. We aim to produce light curves and spectra of hydro models for all types of supernovae. Methods. We extend our model atmosphere code PHOENIX to solve time-dependent non-grey, NLTE, radiative transfer in a special relativistic framework

Li Ma, Liang Cheng

In this short note, we study the gradient estimate of positive solutions to Poisson equation and the non-homogeneous heat equation in a compact Riemannian manifold (M^n,g). Our results extend the gradient estimate for positive harmonic functions and positive solutions to heat equations.

Z. Ahmed, D. S. Akerib, S. Arrenberg, C. N. Bailey

We report on the analysis of the low-energy electron-recoil spectrum from the CDMS II experiment using data with an exposure of 443.2 kg-days. The analysis provides details on the observed counting rate and possible background sources in the energy range of 2 - 8.5 keV. We find no significant excess in the counting rate above background, and compare this obs

R. Zhao, J. Zhou, Th. Koschny, E. N. Economou

We demonstrate theoretically that one can obtain repulsive Casimir forces and stable nanolevitations by using chiral metamaterials. By extending the Lifshitz theory to treat chiral metamaterials, we find that a repulsive force and a minimum of the interaction energy exist for strong chirality, under realistic frequency dependencies and correct limiting value

Da-Chuang Li, Zhuo-Liang Cao

We investigate the entanglement in a two-qubit Heisenberg XYZ system with different Dzyaloshinskii-Moriya(DM) interaction and inhomogeneous magnetic field. It is found that the control parameters ($D_{x}$, $B_{x}$ and $b_{x}$) are remarkably different with the common control parameters ($D_{z}$,$B_{z}$ and $b_{z}$) in the entanglement and the critical temper

Adnan Raja, Vinod M. Prabhakaran, Pramod Viswanath

The linear deterministic model has been used recently to get a first order understanding of many wireless communication network problems. In many of these cases, it has been pointed out that the capacity regions of the network and its reciprocal (where the communication links are reversed and the roles of the sources and the destinations are swapped) are the

Vladimir Bogachev, Giuseppe Da Prato, Michael Röckner

We consider a stochastic differential equation in a Hilbert space with time-dependent coefficients for which no general existence and uniqueness results are known. We prove, under suitable assumptions, existence and uniqueness of a measure valued solution, for the corresponding Fokker--Planck equation. In particular, we verify the Chapman--Kolmogorov equatio

Milan Jirasek, Jan Zeman, Jaroslav Vondrejc

Localization of plastic strain induced by softening can be objectively described by a regularized plasticity model that postulates a dependence of the current yield stress on a nonlocal softening variable defined by a differential (gradient) expression. This paper presents analytical solutions of the one-dimensional localization problem under certain special

L. Gasparov, A. Rush, G. Guntherodt, H. Berger

We report Raman scattering data of single crystals of magnetite (Fe3O4) with Verwey transition temperatures (Tv) of 123 and 117K, respectively. Both single crystals reveal broad electronic background extending up to 900 wavenumbers (~110 meV). Redistribution of this background is observed when samples are cooled below Tv. In particular, spectra of the low te

M. Auriere, G. A. Wade, R. Konstantinova-Antova, C. Charbonnel

Aims: We observe the nearby, weakly-active single giant, Pollux, in order to directly study and infer the nature of its magnetic field. Methods: We used the new generation spectropolarimeters ESPaDOnS and NARVAL to observe and detect circular polarization within the photospheric absorption lines of Pollux. Our observations span 18 months from 2007-2009. We t

S. Veilleux, D. S. N. Rupke, R. Swaters

We report the detection of a complex of extraplanar warm H_2 knots and filaments extending more than ~3 kpc above and below the galactic plane of M82, roughly coincident with the well-known galactic wind in this system. Comparisons of these data with published results at other wavelengths provide quantitative constraints on the topology, excitation, heating,

Koichiro Umetsu

We present the derivation of Hawking radiation by using the tunneling mechanism in a rotating and charged black hole background. We show that the 4-dimensional Kerr-Newman metric, which has a spherically nonsymmetric geometry, becomes an effectively 2-dimensional spherically symmetric metric by using the technique of the dimensional reduction near the horizo

Rodolfo H. Barba, Jesus Maiz Apellaniz, Enrique Perez, Monica Rubio

We present the first high-spatial resolution near-infrared (NIR) imaging of NGC 604, obtained with the NICMOS camera aboard the Hubble Space Telescope (HST). These NICMOS broadband images reveal new NIR point sources, clusters, and diffuse structures. We found an excellent spatial correlation between the 8.4 GHz radio continuum and the 2.2mu-m nebular emissi

A. K. Singh, M. Snure, A. Tiwari, S. Patnaik

We report synthesis of phase pure multiferroic YMnO3 thin films on sapphire (0001)with conducting ZnGaO buffer contact layer. Films were prepared by using pulsed laser deposition technique and characterized using x-ray diffraction(XRD), Scanning electron microscopy (SEM), Energy dispersive absorption spectroscopy (EDAX) and magnetic field dependent dielectri

W. A. Dziembowski, R. Smolec

Data on multimode Cepheids from OGLE-III catalog of the LMC Cepheids are confronted with results from model calculations. Models whose radial mode periods are consistent with observation are not always in agreement with published evolutionary models. Nonradial mode interpretation is considered for the cases of unusual period ratios. The greatest challenge fo

C. Martin Gaskell, Elizabeth S. Klimek

Some progress in understanding AGN variability is reviewed. Reprocessing of X-ray radiation to produce significant amounts of longer-wavelength continua seems to be ruled out. In some objects where there has been correlated X-ray and optical variability, the amplitude of the optical variability has exceeded the amplitude of X-ray variability. We suggest that

Narayanankutty Karuppath, P. Achuthan

The notion of Non-Locality (NL) in physics has great epistemological implications and impact on the perceptive of Reality. Numerous counter intuitive experimental results that clearly violate Bell's inequality have prompted several physicists to believe in 'mysterious' non-local correlations particularly in quantum systems of EPR type. Not commen

G. Raimondo

Surface brightness fluctuations have been proved to be a very powerful technique to determine the distance and characterize the stellar content in extragalactic systems. Nevertheless, before facing the problem of stellar content in distant galaxies, we need to calibrate the method onto nearby well-known systems. In this paper we analyze the properties at $J$

P. A. Evans, A. P. Beardmore, J. P. Osborne, G. A. Wynn

The 2006 outburst of GK Perseii differed significantly at optical and ultraviolet wavelengths from typical outbursts of this object. We present multi-wavelength (X-ray, UV and optical) Swift and AAVSO data, giving unprecedented broad-band coverage of the outburst, allowing us to follow the evolution of the longer-than-normal 2006 outburst across these wavele

Omar Aboura

In this paper, we are dealing with the approximation of the process (Y,Z) solution to the backward doubly stochastic differential equation with the forward process X . After proving the L2-regularity of Z, we use the Euler scheme to discretize X and the Zhang approach in order to give a discretization scheme of the process (Y,Z).

Martin Lemoine, Eli Waxman

This paper proposes and discusses a test of the chemical composition of ultra-high energy cosmic rays that relies on the anisotropy patterns measured as a function of energy. In particular, we show that if one records an anisotropy signal produced by heavy nuclei of charge Z above an energy E_{thr}, one should record an even stronger (possibly much stronger)

L. Gaudreau, A. Kam, G. Granger, S. A. Studenikin

In this paper we report on a tuneable few electron lateral triple quantum dot design. The quantum dot potentials are arranged in series. The device is aimed at studies of triple quantum dot properties where knowing the exact number of electrons is important as well as quantum information applications involving electron spin qubits. We demonstrate tuning stra

J. S. Dowker

The Ray-Singer isospectral theorem (1971) is applied to a general spectral function for Laplacians of twisted p-forms (say) on homogeneous Clifford-Klein factors of the three-sphere. The inducing formulae necessary to express any spectral quantity for any twisting in terms of those for cyclic subgroups of the tetrahedral, octahedral and icosahedral deck grou

Tomas Hruz, Michal Natora, Madhuresh Agrawal

We study stochastic processes that generate non-growing complex networks without self-loops and multiple edges (simple graphs). The work concentrates on understanding and formulation of constraints which keep the rewiring stochastic processes within the class of simple graphs. To formulate these constraints a new concept of wedge distribution (paths of lengt

Jean Dolbeault, Maria J. Esteban, Michael Loss, Gabriella Tarantello

In this paper we prove some new symmetry results for the extremals of the Caffarelli-Kohn-Nirenberg inequalities, in any dimension larger or equal than two.

Sébastien Gouëzel

We prove the almost sure invariance principle for stationary R^d--valued processes (with dimension-independent very precise error terms), solely under a strong assumption on the characteristic functions of these processes. This assumption is easy to check for large classes of dynamical systems or Markov chains, using strong or weak spectral perturbation argu

Viviane Baladi, Sebastien Gouezel

We consider piecewise cone hyperbolic systems satisfying a bunching condition and we obtain a bound on the essential spectral radius of the associated weighted transfer operators acting on anisotropic Sobolev spaces. The bunching condition is always satisfied in dimension two, and our results give a unifying treatment of the work of Demers-Liverani and our p

Richard Walters, Stephen R. Clark, Dieter Jaksch

We study the quantum dynamics of a single qubit coupled to a bath of interacting spins as a model for decoherence in solid state quantum memories. The spin bath is described by the Lipkin-Meshkov-Glick model and the bath spins are subjected to a transverse magnetic field. We investigate the qubit interacting via either an Ising- or an XY-type coupling term t

Agelos Georgakopoulos

We prove that a lamplighter graph of a locally finite graph over a finite graph does not admit a non-constant harmonic function of finite Dirichlet energy.

Garcia de Andrade

A plasma loop twisted Riemannian model is applied to torus dynamos twisted flows it leading to a slow dynamo such as in Moebius strip dynamo, recently considered by Shukurov, Stepanov and Sokoloff [Phys. Rev. \textbf{E 78},025301,(2008)] to modelling Perm dynamo torus in liquid sodium. Since diffusion and advection (stretching), are competing effects for dyn

Alexander Mustill, Mark Wyatt

Detectable debris discs are thought to require dynamical excitation (`stirring'), so that planetesimal collisions release large quantities of dust. We investigate the effects of the secular perturbations of a planet, which may lie at a significant distance from the planetesimal disc, to see if these perturbations can stir the disc, and if so over what ti

E. O. Iltan

We consider a standard model singlet which is accessible to a single extra dimension and its zero mode is localized with Gaussian profile around a point different than the origin. This zero mode scalar is a possible candidate for the dark matter and its annihilation rate is sensitive to the compactification radius of the extra dimension, the localization wid

M. Marchi, S. Azadi, M. Casula, S. Sorella

We introduce a method for accurate quantum chemical calculations based on a simple variational wave function, defined by a single geminal that couples all the electrons into singlet pairs, combined with a real space correlation factor. The method uses a constrained variational optimization, based on an expansion of the geminal in terms of molecular orbitals.

Rieuwert Blok, Corneliu Hoffman

A celebrated theorem of Curtis and Tits on groups with finite BN-pair shows that roughly speaking these groups are determined by their local structure. This result was later extended to Kac-Moody groups by P.~Abramenko and B.~Mühlherr. Their theorem states that a Kac-Moody group $G$ is the universal completion of an amalgam of rank two (Levi) subgroups, as t

Machabeli George, Osmanov Zaza

We have examined the recently detected very high energy (VHE) pulsed radiation from the Crab pulsar. According to the observational evidence, the observed emission (>25GeV) peaks at the same phase with the optical spectrum. Considering the cyclotron instability, we show that the pitch angle becomes non-vanishing leading to the efficient synchrotron mechanism

A. Limosani

Using 605/fb of data collected at the Upsilon(4S) resonance we present a measurement of the inclusive radiative B-meson decay channel, B to X_s gamma. For the lower photon energy thresholds of 1.7, 1.8, 1.9 and 2.0GeV, as defined in the rest frame of the B-meson, we measure the partial branching fraction and the mean and variance of the photon energy spectru

Miron J. Cristea

The current-voltage p-n junction characteristics were mainly analyzed until now at low injection levels and high level injection separately. This work unifies the low injection, medium injection, high injection levels and the ohmic region of the I/V characteristics. Keywords: p-n junctions, current-voltage characteristics, low injection and high injection le

Piotr Gawron

The influence of spontaneous emission channel and generalized Pauli channel on quantum Monty Hall Game is analysed. The scheme of Flittney and Abbott is reformulated using the formalism of density matrices. Optimal classical strategies for given quantum strategies are found. The whole presented scheme illustrates how quantum noise may change the odds of a ze

V. I. Pupyshev, E. A. Pazyuk, A. V. Stolyarov, M. Tamanis

Conventional one-dimensional oscillation theorem is found to be violated for multi-component Schrödinger equations in a general case while for two-component eigenstates coupled by the sign-constant potential operator the following statements are valid: (1) the ground state ($v = 0$) is not degenerate; and (2) the arithmetic mean of nodes $n_1$, $n_2$ for the

Mate Matolcsi, Carlos Vinuesa

We give a slight improvement of the best known lower bound for the supremum of autoconvolutions of nonnegative functions supported in a compact interval. Also, by means of explicit examples we disprove a long standing natural conjecture of Schinzel and Schmidt concerning the extremal function for such autoconvolutions.

Ales Drapal, Carlo Hamalainen, Dan Rosendorf

A latin bitrade (T1, T2) is a pair of partial latin squares which are disjoint, occupy the same set of non-empty cells, and whose corresponding rows and columns contain the same set of entries. A genus may be associated to a latin bitrade by constructing an embedding of the underlying graph in an oriented surface. We report computational enumeration results

Taro Kimura, Tatsuhiro Misumi

We study minimal-doubling fermion actions on hyperdiamond and deformed hyperdiamond lattices, with emphasis on the real-space construction of them and Lorentz covariance of excitations from fermion poles. We propose the improved spatial construction of Creutz fermion action on a deformed hyperdiamond lattice, and discuss conditions for a hyperdiamond-lattice

Darko Mitrovic, Nenad Antonic

We use the continuity of Fourier multiplier operators on $L^p$ to introduce the $H$-distributions --- an extension of $H$-measures in the $L^p$ framework. We apply the $H$-distributions to obtain an $L^p$ version of the localisation principle, and reprove the $L^p$---$L^q$ variant of the Murat--Tartar div-curl lemma.

C. Favre, J. Vitorio Pereira

We give a classification of pairs (F, f) where F is a holomorphic foliation on a projective surface and f is a non-invertible dominant rational map preserving F. We prove that both the map and the foliation are integrable in a suitable sense.

Joseph P. Conlon, Eran Palti

We study gauge threshold corrections for local GUT models in IIB/F-theory. Consistency with holomorphy requirements of supergravity and the Kaplunovsky-Louis formula implies that the unification scale is enhanced by the bulk radius R from the string scale to M_X =RM_S. We argue that the stringy interpretation of this is via a locally uncancelled tadpole sour

Dinesh Kumar Srivastava, Rupa Chatterjee

We explore the intensity correlations for thermal photons having $K_T\leq$ 2 GeV/$c$, for central collisions of heavy nuclei at RHIC and LHC energies. These photons get competing contributions from the quark and the hadronic phases. This competition gives rise to a unique structure, especially in the outward correlation function, due to the interference betw

Nicola Gambino, Gabriele Lobbia

We contribute to the formal theory of pseudomonads, i.e. the analogue for pseudomonads of the formal theory of monads. In particular, we solve a problem posed by Steve Lack by proving that, for every Gray-category K, there is a Gray-category Psm(K) of pseudomonads, pseudomonad morphisms, pseudomonad transformations and pseudomonad modifications in K. We then

R. Versaci

New KLOE results on scalar mesons, $\gamma\gamma$ physics and $\eta$ physics are presented.

E. Nakano, B. -J. Schaefer, B. Stokic, B. Friman

Isentropic trajectories crossing the chiral phase transition near the critical endpoint (CEP) are studied for two light quark flavors. The calculations are performed within an effective chiral model with quark-meson interactions, belonging to the same universality class as QCD. We confront mean-field thermodynamics with the functional renormalization group a

Ki-Seok Kim

We find new mechanism of superconductivity beyond the spin-fluctuation theory, the standard model for unconventional superconductivity in the weak coupling approach, where Kondo fluctuations result in multi-gap superconductivity around an antiferromagnetic quantum critical point of the slave-fermion theory. Fingerprints of the hybridization mechanism are two

Inna, Capdeboscq, Anne Thomas

Let Λbe a minimal Kac-Moody group of rank 2 defined over the finite field F_q, where q = p^a with p prime. Let G be the topological Kac-Moody group obtained by completing Λ. An example is G=SL_2(K), where K is the field of formal Laurent series over F_q. The group G acts on its Bruhat-Tits building X, a tree, with quotient a single edge. We construct new exa

Xiang Liu, Hong-Wei Ke

In this work, we study the radiative open-charm decays $Y(4140)\to {D}_s^{\ast+} D_s^- γ$ and $Y(3930)\to{D}^{\ast+} D^-γ$ under the assignments of $D_{s}^*\bar{D}_s^*$ and $D^*\bar{D}^*$ as molecular states for Y(4140) and Y(3930) respectively. Based on our numerical result, we propose the experimental measurement of the photon spectrum of $Y(4140)\to {D}_s

J. Kroha, M. Klein, A. Nuber, F. Reinert

We propose a new criterion for distinguishing the Hertz-Millis (HM) and the local quantum critical (LQC) mechanism in heavy fermion systems with a magnetic quantum phase transition (QPT). The criterion is based on our finding that the spin screening of Kondo ions can be completely suppressed by the RKKY coupling to the surrounding magnetic ions even without

Sangjib Kim, Soo Teck Lee

We study the structure of a family of algebras which encodes a generalization of the Pieri Rule for the complex orthogonal group. In particular, we show that each of these algebras has a standard monomial basis and has a flat deformation to a Hibi algebra. There is also a parallel theory for the complex symplectic group.

Masaaki Homma, Seon Jeong Kim

We settle the conjecture posed by Sziklai on the number of points of a plane curve over a finite field under the assumption that the curve is nonsingular.

Christopher A. Doran, Leopoldo A. Pando Zayas, Vincent G. J. Rodgers, Kory Stiffler

The leading term for the energy of a bound state of k-quarks and k-antiquarks is proportional to its separation L. These k-string configurations have a Luscher term associated with their quantum fluctuations which is typically a 1/L correction to the energy. We review the status of tensions and Luscher terms in the context of lattice gauge theory, Hamiltonia

E. Shoko, M. F. Smith, Ross H. McKenzie

Understanding the electronic charge distribution around oxygen vacancies in transition metal and rare earth oxides is a scientific challenge of considerable technological importance. We show how significant information about the charge distribution around vacancies in cerium oxide can be gained from a study of high resolution crystal structures of higher ord

Duan Peng-Fei, Ma Wen-Gan, Zhang Ren-You, Han Liang

We report on the next-to-leading order(NLO) QCD computation of top-quark pair production in association with a photon at the Fermilab Tevatron RUN II and CERN Large Hadron Collider(LHC). We describe the impact of the complete NLO QCD radiative corrections to this process, and provide the predictions of the leading order(LO) and NLO integrated cross sections,

Daniel Pertot, Daniel Greif, Stephan Albert, Bryce Gadway

We describe a versatile and simple scheme for producing magnetically and optically-trapped Rb-87 Bose-Einstein condensates, based on a moving-coil transporter apparatus. The apparatus features a TOP trap that incorporates the movable quadrupole coils used for magneto-optical trapping and long-distance magnetic transport of atomic clouds. As a stand-alone dev

Jerome Dedecker, Sebastien Gouezel, Florence Merlevede

We consider a large class of piecewise expanding maps T of [0,1] with a neutral fixed point, and their associated Markov chain Y_i whose transition kernel is the Perron-Frobenius operator of T with respect to the absolutely continuous invariant probability measure. We give a large class of unbounded functions f for which the partial sums of f\circ T^i satisf

A. Foertig, A. Baumann, D. Rauh, V. Dyakonov

We performed temperature dependent transient photovoltage and photocurrent measurements on poly(3-hexylthiophene):[6,6]-phenyl-C61 butyric acid methylester bulk heterojuction solar cells. We found a strongly charge carrier concentration and temperature dependent Langevin recombination prefactor. The observed recombination mechanism is discussed in terms of b

Xavier Sauvage, Cécile Genevois, Gérald Da Costa, Viktor Pantsyrny

The microstructure of a Cu/V nanocomposite wire processed by cold drawing was investigated by high resolution transmission electron microscopy and atom probe tomography. The experimental data clearly reveal some deformation induced interfacial mixing where the vanadium filaments are nanoscaled. The mixed layer is a 2nm wide vanadium gradient in the fcc Cu ph

V. Skokov, A. Illarionov, V. Toneev

Magnetic fields created in the noncentral heavy-ion collision are studied within a microscopic transport model, namely the Ultrarelativistic Quantum Molecular Dynamics model (UrQMD). Simulations were carried out for different impact parameters within the SPS energy range ($E_{lab} = 10 - 158 A$ GeV) and for highest energies accessible for RHIC. We show that

J. Haidenbauer, U. -G. Meißner

The leading order strangeness S=-3 and -4 baryon-baryon interactions are analyzed within chiral effective field theory. The chiral potentials consist of contact terms without derivatives and of one-pseudoscalar-meson exchanges. Assuming SU(3) flavor symmetry those contact terms and the couplings of the pseudoscalar mesons to the baryons are related to the co

Pabitra Pal Choudhury, Swapan Kumar Dutta, Sk. Sarif Hassan, Sudhakar Sahoo

In this paper, we have first given an intuitive definition of "Consciousness" as realized by us. Next, from this intuitive definition we derived the physical definition of quantum consciousness (Quantum Consciousness Parameter or QCP). This QCP is the elementary level of consciousness in quantum particles, which are the most elementary particles in n

G. Lesur, P-Y. Longaretti

(abriged) MRI turbulence is a leading mechanism for the generation of an efficient turbulent transport of angular momentum in an accretion disk through a turbulent viscosity effect. It is believed that the same process could also transport large-scale magnetic fields in disks, reshaping the magnetic structures in these objects. This process, known as turbule

P. G. Kevrekidis, G. J. Herring, S. Lafortune, Q. E. Hoq

We propose a consideration of the properties of the two-dimensional Ablowitz-Ladik discretization of the ubiquitous nonlinear Schrodinger (NLS) model. We use singularity confinement techniques to suggest that the relevant discretization should not be integrable. More importantly, we identify the prototypical solitary waves of the model and examine their stab

I. V. Stasyuk, T. S. Mysakovych

The phase transitions in the Bose-Hubbard model are investigated. A single-particle Green's function is calculated in the random phase approximation and the formalism of the Hubbard operators is used. The regions of existence of the superfluid and Mott insulator phases are established and the $(μ,t)$ (the chemical potential -- transfer parameter) phase d

Cédric Chevalier, François Pellegrini

The parallel ordering of large graphs is a difficult problem, because on the one hand minimum degree algorithms do not parallelize well, and on the other hand the obtainment of high quality orderings with the nested dissection algorithm requires efficient graph bipartitioning heuristics, the best sequential implementations of which are also hard to paralleli

M. G. Ryskin, A. D. Martin, V. A. Khoze, A. G. Shuvaev

We recall the main features of the Regge approach used to understand soft interactions at LHC and higher energies. Unitarity tames the power growth of the elastic proton-proton scattering amplitude with energy, and leads to the migration of the secondary particles produced in high-energy proton-proton collisions to larger transverse momenta. We discuss, in q

B. Cedres, J. Iglesias-Paramo, J. M. Vilchez, D. Reverte

This paper presents the first results of an Halpha imaging survey of galaxies in the central regions of the A2151 cluster. A total of 50 sources were detected in Halpha. The morphologies of the 43 H$α$ selected galaxies range from grand design spirals and interacting galaxies to blue compacts and tidal dwarfs or isolated extragalactic HII regions, spanning a

Manjish Pal

The {\sc $c$-Balanced Separator} problem is a graph-partitioning problem in which given a graph $G$, one aims to find a cut of minimum size such that both the sides of the cut have at least $cn$ vertices. In this paper, we present new directions of progress in the {\sc $c$-Balanced Separator} problem. More specifically, we propose a new family of mathematica

Marie Cottrell, Patrice Gaubert, Cédric Eloy, Damien François

Aircraft engines are designed to be used during several tens of years. Their maintenance is a challenging and costly task, for obvious security reasons. The goal is to ensure a proper operation of the engines, in all conditions, with a zero probability of failure, while taking into account aging. The fact that the same engine is sometimes used on several air

R H Colman, T Fennell, C Ritter, G Lau

Ni2SiO4, Liebenbergite, is an example of a quasi-one-dimensional magnet made up of frustrated corner sharing triangles of Ni2+ (S = 1) ions that propagate parallel to the b axis. Ni2SiO4 is isostructural with olivine, a common mineral of varying composition Fe2-xMgxSiO4, and is described in the orthorhombic space group Pnma. A synthetic polycrystalline sampl

L. Jelinek, R. Marques

It is shown that artificial magnetism with relatively large frequency bandwidth can be obtained from periodic arrangements of dielectric rings. Combined with dielectric rods, dielectric rings can provide 3D isotropic left-handed metamaterials being an advantageous alternative to metallic split ring resonators and/or metallic wires when un-detectability by lo

Yiping Wang, Toru Yamada, Ichi Tanaka, Masanori Iye

We have obtained deep images in the BVRIJHKs bands of the field centered on QSO 1508+5714 (z_{em} =4.28) with the Suprime camera, FOCAS and MOIRCS cameras on Subaru telescope. We report here the detection of a B-dropout galaxy, which is $3\secpoint 5$ north-west of the QSO sightline. A photometric redshift analysis is presented to complement the color select

A Poole, A S Wills, P J Brown

The electric-field dependence of the magnetic structure of multiferroic MnWO4 has been investigated using spherical neutron polarimetry as a function of temperature. The application of an electric field drives the magnetic structure to a single chiral domain. The magnitude of the field required to do this is shown to increase with temperature. The link betwe

Marko Bračko

Belle and BaBar experiments at the KEKB and PEP-II B-factories provide also an excellent environment for spectroscopy studies. In this report we present recent results in the field of charmonium spectroscopy, focusing on new charmonium-like states observed in B decays, and on $J^{PC}=1^{--}$ resonances created in $e^+ e^-$ annihilation through the photon rad

Jean-François Couchot, Alain Giorgetti, Nicolas Stouls

Increasing the automaticity of proofs in deductive verification of C programs is a challenging task. When applied to industrial C programs known heuristics to generate simpler verification conditions are not efficient enough. This is mainly due to their size and a high number of irrelevant hypotheses. This work presents a strategy to reduce program verificat

Yves Gallot, Pieter Moree, Wadim Zudilin

If the equation of the title has an integer solution with $k\ge2$, then $m>10^{9.3\cdot10^6}$. This was the current best result and proved using a method due to L. Moser (1953). This approach cannot be improved to reach the benchmark $m>10^{10^7}$. Here we achieve $m>10^{10^9}$ by showing that $2k/(2m-3)$ is a convergent of $\log2$ and making an extensive co

Dirk-Gunnar Welsch, Werner Vogel, Tomas Opatrny

A review is given on phase-sensitive measurements, such as homodyne detection, for radiation fields and material systems. Methods of quantum-state reconstruction are considered for radiation fields, including multimode and pulsed radiation. For matter systems, methods are reported for the reconstruction of quantum states of molecular vibrations, the quantize

Raimar Wulkenhaar

In order to extend the spectral action principle to non-compact spaces, we propose a framework for spectral triples where the algebra may be non-unital but the resolvent of the Dirac operator remains compact. We show that an example is given by the supersymmetric harmonic oscillator which, interestingly, provides two different Dirac operators. This leads to

A. A. Bukharov, A. S. Ovchinnikov, N. V. Baranov, K. Inoue

Motivated by recent experimental results reporting giant coercive fields in Co(II)-based molecular magnets we present a theory of hysteresis phenomena based on the Glauber stochastic dynamics. Unusual form of hysteresis loops is similar to those of found in Co-based quasi-one-dimensional ferrimagnet CoPhOMe at low temperatures. Temperature dependence of the

M. Mirea

A dynamical pair breaking effect is evidenced at very low excitation energies. For this purpose, a new set of time-dependent coupled channel equations for pair-breaking in superfluid systems are deduced from the variational principle. These equations give the probability to destroy or to create a Cooper pair under the action of some perturbations or when the

Y. Tsutsumi, K. Machida

Motivated by the on-going rotating cryostat experiments in ISSP, Univ. of Tokyo, we explore the textures and vortices in superfluid 3He-A phase confined in narrow cylinders, whose radii are R=50mum and 115mum. The calculations are based on the Ginzburg-Landau (GL) framework, which fully takes into account the orbital (l-vector) and spin (d-vector) degrees of

M. Hayashida, G. Bonnoli, A. Stamerra, E. Lindfors

We performed simultaneous multiwavelength observations of OJ 287 with the Nobeyama Millimeter Array for radio, the KANATA telescope and the KVA telescope for optical, the Suzaku satellite for X-ray and the MAGIC telescope for very high energy (VHE) gamma-ray in 2007. The observations were conducted for a quiescent state in April and in a flaring state in Nov

Francesc Ferrer

In string gas cosmology, the extra dimensions of the underlying theory are kept at a microscopic scale by a gas of strings. In the matter-dominated era, however, dust pressure can lead to oscillations of the extra dimensions and to acceleration in the three visible dimensions, even with a vanishing cosmological term. We review the resulting oscillating expan

Xueliang Li, Hongping Ma

The energy $E(G)$ of a graph $G$ is defined as the sum of the absolute values of its eigenvalues. Let $S_2$ be the star of order 2 (or $K_2$) and $Q$ be the graph obtained from $S_2$ by attaching two pendent edges to each of the end vertices of $S_2$. Majstorović et al. conjectured that $S_2$, $Q$ and the complete bipartite graphs $K_{2,2}$ and $K_{3,3}$ are

Grigoriy Blekherman

We study dimensions of the faces of the cone of nonnegative polynomials and the cone of sums of squares; we show that there are dimensional differences between corresponding faces of these cones. These dimensional gaps occur in all cases where there exist nonnegative polynomials that are not sums of squares. As either the degree or the number of variables gr

Joy Morris, Cheryl E. Praeger, Pablo Spiga

In this paper, we examine the structure of vertex- and edge-transitive strongly regular graphs, using normal quotient reduction. We show that the irreducible graphs in this family have quasiprimitive automorphism groups, and prove (using the Classification of Finite Simple Groups) that no graph in this family has a holomorphic simple automorphism group. We a

Mario Castagnino, Sebastian Fortin, Roberto Laura, Olimpia Lombardi

A general theoretical framework for decoherence is proposed, which encompasses formalisms originally devised to deal just with open or with closed systems. The conditions for decoherence are clearly stated and the relaxation and decoherence times are compared. Finally, the spin-bath model is developed in detail from the new perspective.

I. V. Bondarev, L. M. Woods, K. Tatur

We study theoretically the interactions of excitonic states with surface electromagnetic modes of small-diameter (~1 nm) semiconducting single-walled carbon nanotubes. We show that these interactions can result in strong exciton-surface-plasmon coupling. The exciton absorption line shape exhibits Rabi splitting ~0.1 eV as the exciton energy is tuned to the n

Xiaotie Deng, Qi Qi, Amin Saberi

We study the envy-free cake-cutting problem for $d+1$ players with $d$ cuts, for both the oracle function model and the polynomial time function model. For the former, we derive a $θ(({1\overε})^{d-1})$ time matching bound for the query complexity of $d+1$ player cake cutting with Lipschitz utilities for any $d> 1$. When the utility functions are given by a

T. J. Haigh, A. J. Ferris, M. K. Olsen

The availability of Bose-Einstein condensates as mesoscopic or macroscopic quantum objects has aroused new interest in the possiblity of making and detecting coherent superpositions involving many atoms. In this article we show that it may be possible to generate such a superposition state in a reasonably short time using Feshbach resonances to tune the inte

Kaden R. A. Hazzard, Erich J. Mueller

We calculate the radio-frequency spectrum of a trapped cloud of cold bosonic atoms in an optical lattice. Using random phase and local density approximations we produce both trap averaged and spatially resolved spectra, identifying simple features in the spectra that reveal information about both superfluidity and correlations. Our approach is exact in the d