January 2004 arXiv papers — page 20

W. Krolikowski

In the framework of seesaw mechanism with three neutrino flavors, we propose tentatively an efficient parametrization for the spectra of Dirac and righthanded Majorana neutrino mass matrices in terms of three free parameters. Two of them are related to (and determined by) the corresponding parameters introduced previously for the mass spectra of charged lept

Ron-Chou Hsieh, Chuan-Hung Chen

We study the indication of large different branching ratios between $B^{-}\to D^{(*)0} K^{-} {K}^{0}$ and $\bar{B}_{d}\to D^{(*)+} K^{-} {K}^{0}$ observed by Belle. Interestingly, the same situation is not found in the decays $B\to D^{(*)} K^{-} {K}^{*0}$. If there exist no intermediate resonances in the decays $B^{-}\to D^{(*)0} K^{-} {K}^{0}$, a puzzle wil

Xavier Calmet

In this article we consider the bounds on the noncommutative nature of space-time. We argue that these bounds are extremely model dependent. In the only phenomenologically viable framework, i.e. when the fields are taken to be in the enveloping of the Lie algebra, the constraints are fairly loose and only of the order of a few TeV.

Jiao Lin Xu

From the Dirac sea concept and the Quark Model, we infer a phenomenological accompanying excitation concept. This concept will give an explanation for the confinement of quarks.

A. Rajantie

Thermal fluctuations of the gauge field lead to monopole formation at the grand unified phase transition in the early Universe, even if the transition is merely a smooth crossover. The dependence of the produced monopole density on various parameters is qualitatively different from theories with global symmetries, and the monopoles have a positive correlatio

Alain Bellerive

This paper reviews the constraints imposed on the solar neutrino mixing parameters by data collected by the Sudbury Neutrino Observatory (SNO). The SNO multivariate analysis is reviewed. The global solar neutrino analysis is emphasized in terms of matter-enhanced oscillation of two active flavors. An outline of how SNO uses the data to produce oscillation co

ZEUS Collaboration

The photoproduction of $D^{*\pm} (2010)$ mesons associated with a leading neutron has been observed with the ZEUS detector in $ep$ collisions at HERA using an integrated luminosity of 80 pb$^{-1}$. The neutron carries a large fraction, {$x_L>0.2$}, of the incoming proton beam energy and is detected at very small production angles, {$θ_n<0.8$ mrad}, an indica

D. Bandurin, N. Skachkov

The number of events suitable for a determination of the gluon distribution function g(x,Q^2) in a proton at the LHC for various intervals of x and Q^2 are estimated. The contributions of main background sources to ``direct photon+jet&#39;&#39; production processes are studied. The values of discrimination powers between quark and gluon jets as well as betwe

M. Sharif

We investigate matter symmetries of cylindrically symmetric static spacetimes. These are classified for both cases when the energy-momentum tensor is non-degenerate and also when it is degenerate. It is found that the non-degenerate energy-momentum tensor gives either three, four, five, six, seven or ten independent matter collineations in which three are is

G. M. Kremer

The evolution of a Universe confined onto a 3-brane embedded in a five-dimensional space-time is investigated where the cosmological fluid on the brane is modeled by the van der Waals equation of state. It is shown that the Universe on the brane evolves in such a manner that three distinct periods concerning its acceleration field are attained: (a) an initia

Yousuke Itoh

A third post-Newtonian (3 PN) equation of motion for two spherical compact stars in a harmonic coordinate has been derived based on the surface integral approach and the strong field point particle limit. The strong field point particle limit enables us to incorporate a notion of a self-gravitating regular star into general relativity. The resulting 3 PN equ

Simona Cocco, Remi Monasson

An analysis of the average-case complexity of solving random 3-Satisfiability (SAT) instances with backtrack algorithms is presented. We first interpret previous rigorous works in a unifying framework based on the statistical physics notions of dynamical trajectories, phase diagram and growth process. It is argued that, under the action of the Davis--Putnam-

Nicolas Christin, John Chuang

In this paper, we model the cost incurred by each peer participating in a peer-to-peer network. Such a cost model allows to gauge potential disincentives for peers to collaborate, and provides a measure of the ``total cost&#39;&#39; of a network, which is a possible benchmark to distinguish between proposals. We characterize the cost imposed on a node as a f

M. Dejmek, R. Folch, A. Parisi, M. Plapp

The phase-field method has become in recent years the method of choice for simulating microstructural pattern formation during solidification. One of its main advantages is that time-dependent three-dimensional simulations become feasible. This makes it possible to address long-standing questions of pattern stability. Here, we investigate the stability of he

J. D. Lee

We study the dynamics of spins in the canted antiferromagnetic hematite nanoparticles $α$-Fe$_2$O$_3$. The system includes an antiferromagnetic exchange ($J$) between two sublattices as well as the potential dominated by a uniaxial anisotropy and dissipates through the thermally triggered spin-phonon mechanism. The exchange $J$ is found to reduce the superpa

Z. Wu, D. J. Singh, R. E. Cohen

We report calculations of the electronic structure of CaB$_6$ using the weighted density approximation (WDA) to density functional theory. We find a semiconducting band structure with a sizable gap, in contrast to local density approximation (LDA) results, but in accord with recent experimental data. In particular, we find an $X$-point band gap of 0.8 eV. Th

A. Monaco, T. Scopigno, P. Benassi, A. Giugni

The high frequency collective dynamics of molten potassium has been investigated by inelastic x-ray scattering, disclosing an energy/momentum transfer region unreachable by previous neutron scattering experiments (INS). We find that a two-step relaxation scenario, similar to that found in other liquid metals, applies to liquid potassium. In particular, we sh

V. Podzorov, M. E. Gershenson, Ch. Kloc, R. Zeis

We report on fabrication of novel field-effect transistors (FETs) based on transition metal dichalcogenides. The unique structure of single crystals of these layered inorganic semiconductors enables fabrication of FETs with intrinsically low field-effect threshold and high charge carrier mobility, comparable to that in the best single-crystal Si FETs (up to

S. Dusuel, D. Zanchi

We study the effects of non-magnetic impurities on the phase diagram of a system of interacting electrons with a flat Fermi surface. The one-loop Wilsonian renormalization group flow of the angle dependent diffusion function $D(θ_1,θ_2,θ_3)$ and interaction $U(θ_1,θ_2,θ_3)$ determines the critical temperature and the nature of the low temperature state. As t

Ar. Abanov, Andrey V. Chubukov

We argue that recently observed superconductivity-induced blue shift of the plasma frequency $δω_{pl}$ in $Bi_2Sr_2CaCu_2O_{8+δ}$ is related to the change in the integrated dynamical structure factor associated with the development of the spin resonance below $T_c$. We show that the magnitude of $δω_{pl}$ is consistent with the small integrated spectral weig

Olivier Cepas, Timothy Ziman

We consider the absorption of light with emission of one S(tot)=1 magnetic excitation in systems with a spin gap induced by quantum fluctuations. We argue that an electric dipole transition is allowed on the condition that a virtual phonon instantaneously breaks the inversion symmetry. We derive an effective operator for the transition and argue that the pro

L. M. Fisher, A. V. Kalinov, I. F. Voloshin, V. A. Yampol&#39;skii

The effect of the transverse AC magnetic field on relaxation process in YBa$_2$Cu$_3$O$_x$ melt-textured superconductor was studied. A factor of 50 suppression of the relaxation rate could be achieved at the expense of some reduction in the maximum trapped field, with the magnetic-induction gradient being unchanged. This phenomenon is interpreted as a result

Ludger Wirtz, Michal Dallos, Hans Lischka, Joachim Burgdorfer

We discuss the feasibility of the embedded cluster approach for it ab-initio calculations of charge exchange between ions and a LiF surface. We show that the discrete density of valence states in embedded clusters converges towards the continuum limit of the density of states in the valence band of an infinitely extended LiF surface. Screening of the holes t

Marc Mezard

This talk surveys the recent development of message passing procedures for solving constraint satisfaction problems. The cavity method from statistical physics provides a generalization of the belief propagation strategy that is able to deal with the clustering of solutions in these problems. It allows to derive analytic results on their phase diagrams, and

Fabien Alet, Erik S. Sorensen

The generic transition in the boson Hubbard model, occurring at an incommensurate chemical potential, is studied in the link-current representation using the recently developed directed geometrical worm algorithm. We find clear evidence for a multi-peak structure in the energy distribution for finite lattices, usually indicative of a first order phase transi

D. W. McComb, A. J. Craven, L. Chioncel, A. I. Lichtenstein

The energy-loss near-edge structure (ELNES) at the oxygen $K$ edge in two $AB_2O_4$ spinels (A=Mg, B=Al,Cr) is reported. In $MgAl_2O_4$ the experimental data is successfully modelled within the LDA framework. In the case of $MgCr_2O_4$ spin-polarisation, in the form of antiferromagnetic ordering on the Cr sub-lattice, must be included despite the fact that t

V. I. Yukalov, E. P. Yukalova

A mixture of the multicomponent Bose-Einstein condensate is considered, where each component moves with its own velocity. As a result of the relative motion, the mixture stratifies when the relative velocity reaches a critical value. Stability conditions for a binary moving mixture are derived and the critical velocity is found.

H. -U. Habermeier

Using oxide substrates for functional ceramic thin film deposition beyond their usual application as chemical inert, lattice-matched support for the films represents a novel concept in ceramic thin film research. The substrates are applied as a functional element in order to controllably modify the atom arrangement and the growth mode of ceramic prototype ma

B. Beckmann, U. Nowak, K. D. Usadel

Experimentally an asymmetry of the reversal modes has been found in certain exchange bias systems. From a numerical investigation of the domain state model evidence is gained that this effect depends on the angle between the easy axis of the antiferromagnet and the applied magnetic field. Depending on this angle the ferromagnet reverses either symmetrically,

L. N. Shchur, M. A. Novotny

We analyze the evolution of the local simulation times (LST) in Parallel Discrete Event Simulations. The new ingredients introduced are i) we associate the LST with the nodes and not with the processing elements, and 2) we propose to minimize the exchange of information between different processing elements by freezing the LST on the boundaries between proce

R. V. R. Pandya

In this paper, Langevin model equation is proposed for Fourier modes of velocity field of isotropic turbulence whose statistical properties are identical to those governed by equations of Self-Consistent-Field (SCF) theory of turbulence [J. R. Herring, Physics of Fluids 9, 2106 (1966)].

Gregory Berkolaiko, Michael Grinfeld

We study the number of periodic solutions in two first order non-autonomous differential equations both of which have been used to describe, among other things, the mean magnetization of an Ising magnet in the time-varying external magnetic field. When the strength of the external field is varied, the set of periodic solutions undergoes a bifurcation in both

Iacopo Carusotto, Erich J. Mueller

We explore the dielectric properties of spinor condensates. Gases with vector (nematic) order, such as spin-1 condensates with ferromagnetic (antiferromagnetic) interactions, display optical activity (birefringence). This optical activity/birefringence is respectively seen for light detuned from resonance by a frequency which is not too large compared with t

M. C. Goorden, Ph. Jacquod, C. W. J. Beenakker

We calculate the sample-to-sample fluctuations in the excitation gap of a chaotic dynamical system coupled by a narrow lead to a superconductor. Quantum fluctuations on the order of magnitude of the level spacing, predicted by random-matrix theory, apply if $τ_E\ll\hbar/E_T$ (with $τ_E$ the Ehrenfest time and $E_T$ the Thouless energy). For $τ_E\agt\hbar/ E_

T. Neuhaus, A. Rajantie, K. Rummukainen

The three-dimensional integer-valued lattice gauge theory, which is also known as a &#34;frozen superconductor,&#34; can be obtained as a certain limit of the Ginzburg-Landau theory of superconductivity, and is believed to be in the same universality class. It is also exactly dual to the three-dimensional XY model. We use this duality to demonstrate the prac

Tyler L. Bourke, Alyssa A. Goodman

Magnetic fields are believed to play an important role in the evolution of molecular clouds, from their large scale structure to dense cores, protostellar envelopes, and protoplanetary disks. How important is unclear, and whether magnetic fields are the dominant force driving star formation at any scale is also unclear. In this review we examine the observat

Ravi Subrahmanyan, Avinash A. Deshpande

Interferometric telescopes made of close-packed antenna elements are an important tool for imaging extended radio sources, specifically structures that have angular sizes comparable to or even greater than the FWHM of the beams of the antennas. They have proved useful in observations of cosmic microwave background anisotropies that require high brightness-se

S. I. Ipatov

Trans-Neptunian objects (TNOs) with diameter d>100 km moving now in not very eccentric orbits could be formed directly by the compression of large rarefied dust condensations (with semi-major axes a>30 AU), but not by the accretion of smaller solid planetesimals. A considerable portion of TNO binaries could be formed at the stage of compression of condensati

Yoel Rephaeli

RXTE and BeppoSAX observations have yielded evidence for the presence of a secondary power-law spectral component in the spectra of several clusters of galaxies. This emission in clusters with extended regions of radio emission is likely to be by relativistic electrons that are Compton scattered by the CMB. The radio and non-thermal (NT) X-ray measurements y

M. Turler, T. J. -L. Courvoisier, S. Chaty, Y. Fuchs

The true nature of the radio emitting material observed to be moving relativistically in quasars and microquasars is still unclear. The microquasar community usually interprets them as distinct clouds of plasma, while the extragalactic community prefers a shock wave model. Here we show that the synchrotron variability pattern of the microquasar GRS 1915+105

G. Altavilla, G. Fiorentino, M. Marconi, I. Musella

We investigate how a different calibration of the Cepheid Period-Luminosity (PL) relation taking into account the metallicity corrections, affects the absolute magnitude calibration of Supernovae (SNe) Ia and, in turn, the determination of the Hubble constant H_0. We exploit SN Ia light curves from literature and previously unpublished data, to build the M_B

T. Di Girolamo, G. Di Sciascio, S. Vernetto

ARGO-YBJ is a &#34;full coverage&#34; air shower detector under construction at the YangBaJing Laboratory (4300 m a.s.l., Tibet, P.R. of China). Its main goals are gamma-ray astronomy and cosmic ray studies. In this paper we present the capabilities of ARGO-YBJ in detecting the emission from Gamma Ray Bursts (GRBs) at energies E>10 GeV.

J. -U. Ness, J. H. M. M. Schmitt, S. J. Wolk, K. Dennerl

We report the first unambiguous detection of X-ray emission originating from Saturn with a Chandra observation, duration 65.5 ksec with ACIS-S3. Beyond the pure detection we analyze the spatial distribution of X-rays on the planetary surface, the light curve, and some spectral properties. The detection is based on 162 cts extracted from the ACIS-S3 chip with

P. Mimica, M. -A. Aloy, E. Mueller, W. Brinkmann

We present the results of relativistic hydrodynamic simulations of the collision of two dense shells in a uniform external medium, as envisaged in the internal shock model for BL Lac jets. The non-thermal radiation produced by highly energetic electrons injected at the relativistic shocks is computed following their temporal and spatial evolution. The accele

A. Szostek, A. A. Zdziarski

We present an analysis of Cyg X-3 data from RXTE/PCA,HEXTE and ASM, supplemented by a selected spectrum from BeppoSAX. We fit the PCA/HEXTE spectra from 1996-2000 by a model including hybrid Comptonization, reflection and absorption, and classify them into hard, intermediate and soft states. Apart from the very strong absorption in Cyg X-3, the spectra resem

S. Vaughan, R. Edelson, R. S. Warwick

We report on exploratory Chandra observations of five galactic nuclei that were found to be X-ray bright during the ROSAT all-sky survey (with L_X > 10^43 erg s^-1) but subsequently exhibited a dramatic decline in X-ray luminosity. Very little is known about the post-outburst X-ray properties of these enigmatic sources. In all five cases Chandra detects an X

Gajendra Pandey, David L. Lambert, N. Kameswara Rao, C. Simon Jeffery

Analysis of HST STIS ultraviolet spectra of two hot extreme helium stars (EHes): V1920 Cyg and HD 124448 provide the first measurements of abundances of neutron-capture elements for EHes. Although the two stars have similar abundances for elements up through the iron-group, they differ strikingly in their abundances of heavier elements: V1920 Cyg is enriched

M. Messineo, H. J. Habing, K. M. Menten, A. Omont

We present a compilation and study of DENIS, 2MASS, ISOGAL, MSX and IRAS 1--25 micron photometry for a sample of 441 late-type stars in the inner Galaxy, which we previously searched for 86 GHz SiO maser emission (Messineo et al.2002). The comparison of the DENIS and 2MASS J and Ks magnitudes shows that most of the SiO targets are indeed variable stars. The

N. Menci, F. Fiore, G. C. Perola, A. Cavaliere

We have incorporated the description of the X-ray properties of Active Galactic Nuclei (AGNs) into a semi-analytic model of galaxy formation, adopting physically motivated scaling laws for accretion triggered by galaxy encounters. Our model reproduces the level of the cosmic X-ray background at 30 keV; we predict that the largest contribution (around 2/3) co

David L. Lambert, Bacham E. Reddy

Lithium abundances are presented for a sample of 181 nearby F and G dwarfs with accurate {\it Hipparcos} parallaxes. The stars are on circular orbits about the Galactic centre and, hence, are identified as belonging to the thin disk. This sample is combined with two published surveys to provide a catalogue of lithium abundances, metallicities ([Fe/H]), masse

N. Kuno, N. Sato, H. Nakanishi, A. Yamauchi

We present the results of the radio observations of the afterglow of GRB 030329 with the Nobeyama 45-m telescope. The observations were made at 23.5 GHz, 43 GHz, and 90 GHz. The light curves show steep decline after constant phase. The start time of the decline depends on frequency. Namely, the decline started earlier at higher frequency. The spectrum has a

Paul J. Francis, Gerard M. Williger

We present high resolution spectroscopy of a QSO whose sight-line passes through the halo of a pair of elliptical galaxies at redshift 2.38. This pair of galaxies probably lies at the center of a galaxy proto-cluster, and is embedded in a luminous extended Ly-alpha nebula. The QSO sight-line intersects two small gas clouds within this halo. These clouds have

Marc J. Kuchner

The last few years have seen a variety of new image mask designs for diffraction-limited coronagraphy. Could there still be useful designs as yet undiscovered? To begin to answer this question, I survey and unify the Fraunhofer theory of coronagraph image masks in the context of a one-dimensional classical coronagraph. I display a complete solution to the pr

A. Rajantie

Topological defects are common in many everyday systems. In general, they appear if a symmetry is broken at a rapid phase transition. In this article, I explain why it is believed that they should have also been formed in the early universe and how that would have happened. If topological defects are found, this will provide a way to study observationally th

Andrew Chamblin

We extend Bousso&#39;s notion of a lightsheet - a surface where entropy can be defined in a way so that the entropy bound is satisfied - to more general surfaces. Intuitively these surfaces may be regarded as deformations of the Bousso choice; in general, these deformations will be timelike and so we refer to them as `timesheets&#39;. We show that a timeshee

Gerald A. Goldin, Vladimir Shtelen

We generalize classical Yang-Mills theory by extending nonlinear constitutive equations for Maxwell fields to non-Abelian gauge groups. Such theories may or may not be Lagrangian. We obtain conditions on the constitutive equations specifying the Lagrangian case, of which recently-discussed non-Abelian Born-Infeld theories are particular examples. Some models

Gerald Kaiser

A necessary and sufficient condition for energy-momentum conservation is proved within a topological, pre-metric approach to classical electrodynamics including magnetic as well as electric charges. The extended Lorentz force, consisting of mutual actions by F=(E, B) on the electric current and G=(H, D) on the magnetic current, can be derived from an energy-

Graham Niblo, Michah Sageev, Peter Scott, Gadde A. Swarup

We combine ideas of Scott and Swarup on good position for almost invariant subsets of a group with ideas of Sageev on constructing cubings from such sets. We construct cubings which are more canonical than in Sageev&#39;s original construction. We also show that almost invariant sets can be chosen to be in very good position.

B. -G. Park, D. L. DePoy, B. S. Gaudi, A. Gould

We analyze the Galactic bulge microlensing event MOA-2003-BLG-37. Although the Einstein timescale is relatively short, t_e=43 days, the lightcurve displays deviations consistent with parallax effects due to the Earth&#39;s accelerated motion. We show that the chi^2 surface has four distinct local minima that are induced by the ``jerk-parallax&#39;&#39; degen

Adrian C. Pope, Takahiko Matsubara, Alexander S. Szalay, Michael R. Blanton

We present estimates of cosmological parameters from the application of the Karhunen-Loeve transform to the analysis of the 3D power spectrum of density fluctuations using Sloan Digital Sky Survey galaxy redshifts. We use Omega_m*h and f_b = Omega_b/Omega_m to describe the shape of the power spectrum, sigma8 for the (linearly extrapolated) normalization, and

B. Julia-Diaz, D. O. Riska

It is shown that the phenomenological description of the baryon magnetic moments in the quark model carries over to the Poincaré covariant extension of the model. This applies to all the three common forms of relativistic kinematics with structureless constituent currents, which are covariant under the corresponding kinematic subgroups. In instant and front

Michael K. -H. Kiessling, Carlo Lancellotti

We discuss the relationship between kinetic equations of the Fokker-Planck type (two linear and one non-linear) and the Kolmogorov (a.k.a. master) equations of certain N-body diffusion processes, in the context of Kac&#39;s &#34;propagation of chaos&#34; limit. The linear Fokker-Planck equations are well-known, but here they are derived as a limit N->infty o

M. N. Huda, A. K. Ray

Hydrogen adsorption on delta-Pu (100) and (111) surfaces using the generalized gradient approximation of the density functional theory with Perdew and Wang functionals have been studied at both the spin-polarized level and the non-spin-polarized level. For the (100) surface at the non-spin-polarized level, we find that the center position of the (100) surfac

Ming-Qiu Huang, Dao-Wei Wang

The exclusive semileptonic heavy baryon decay Λ_b\to p l\barνis investigated using light-cone sum rule method in both full QCD and HQET. The form factors describing the decay are calculated and used to predict the decay width and differential distribution. The total decay width obtained from full QCD is in agreement with the previous theoretical predictions

Thomas Gasenzer

We investigate theoretically the molecular yield in photoassociation of Bose-Einstein condensed sodium atoms for light intensities of the order of and above those applied in a recent experiment. Our results show that the rate at which ground state molecules may be formed saturates at high light intensities whereas the loss rate of condensate atoms does not.

Fay Dowker, Isabelle Herbauts

We present simulations of causal dynamical collapse models of field theories on a 1+1 null lattice. We use our simulations to compare and contrast two possible interpretations of the models, one in which the field values are real and the other in which the state vector is real. We suggest that a procedure of coarse graining and renormalising the fundamental

Dmitrij V. Soroka, Vyacheslav A. Soroka

The Schouten-Nijenhuis bracket is generalized for the superspace case and for the Poisson brackets of opposite Grassmann parities.

K. Kovarik, C. Weber, H. Eberl, W. Majerotto

We have calculated the complete one-loop corrections to the sfermion pair production process e+e- -> sf_i sf_j (f = t, b, tau, tau-neutrino) in the Minimal Supersymmetric Standard Model. Our results also include the previously calculated SUSY-QCD corrections. We present the details of the renormalization scheme used. It is found that the weak corrections are

Joao Magueijo, Lee Smolin

We consider a prescription for introducing deformed dispersion relations in the bosonic string action. We find that in a subset of such theories it remains true that the embedding coordinates propagate linearly on the worldsheet. While both the string modes and the center of mass propagate with deformed dispersion relations, the speed of light remains energy

Simon Hands, David N. Walters

We present results of numerical simulations of the 3+1 dimensional Nambu - Jona-Lasinio (NJL) model with a non-zero baryon density enforced via the introduction of a chemical potential mu not equal to 0. The triviality of the model with a number of dimensions d>=4 is dealt with by fitting low energy constants, calculated analytically in the large number of c

Signe Seidelin, Rodolphe Hoppeler, Olivier Sirjean, Denis Boiron

We report an experiment measuring simultaneously the temperatureand the flux of ions produced by a cloud of triplet metastablehelium atoms at the Bose-Einstein critical temperature. The onsetof condensation is revealed by a sharp increase of the ion fluxduring evaporative cooling. Combining our measurements withprevious measurements of ionization in a pure B

Radoslaw Maj, Stanislaw Mrowczynski

The asymptotic form of the plane wave decomposition into spherical waves, which is used to express the scattering amplitude in terms of phase shifts, is incorrect. We explain why and show how to circumvent the mathematical inconsistency.

Paolo Cea, Leonardo Cosmai, Massimo D&#39;Elia

We investigate the deconfining phase transition in SU(3) pure gauge theory and in full QCD with two flavors of staggered fermions. The phase transition is detected by measuring the free energy in presence of an abelian monopole background field. In the pure gauge case our finite size scaling analysis is in agreement with the well known presence of a weak fir

Donghyun Kim, Yoonbai Kim, JungJai Lee

We study O($N+1$) nonlinear $σ$-model in $(p+1+N)$-dimensional curved spacetime with negative cosmological constant, and find a new $σ$-lump solution with half-integer winding and divergent energy. When the spatial structure of $N$ extra-dimensions is determined by this global defect, a black $σp$-brane surrounded by the degenerated horizon is formed and its

Yun-Song Piao, Yuan-Zhong Zhang

In this paper we study the inflation model driven by the phantom field. We propose a possible exit from phantom inflation to our observational cosmology by introducing an additional normal scalar field, similar to hybrid inflation model. Then we discuss the primordial perturbation spectra from various phantom inflation models and give an interesting compare

P. Contucci, C. Giardina&#39;, J. Pule&#39;

We provide a very simple proof for the existence of the thermodynamic limit for the quenched specific pressure for classical and quantum disordered systems on a $d$-dimensional lattice, including spin glasses. We develop a method which relies simply on Jensen&#39;s inequality and which works for any disorder distribution with the only condition (stability) t

P. Warszawski, Jay Gambetta, H. M. Wiseman

We investigate the effect of imperfections in realistic detectors upon the problem of quantum state and parameter estimation by continuous monitoring of an open quantum system. Specifically, we have reexamined the system of a two-level atom with an unknown Rabi frequency introduced by Gambetta and Wiseman [Phys. Rev. A 64, 042105 (2001)]. We consider only di

A. A. Raduta, A. Escuderos, A. Faessler, E. Moya de Guerra

Four nuclei which are proved to be $2νββ$ emitters ($^{76}$Ge, $^{82}$Se, $^{150}$Nd, $^{238}$U), and four suspected, due to the corresponding Q-values, to have this property ($^{148}$Nd, $^{154}$Sm, $^{160}$Gd, $^{232}$Th), were treated within a proton-neutron quasiparticle random phase approximation (pnQRPA) with a projected spherical single particle basis

J. Fleischer, O. V. Tarasov, V. O. Tarasov

An analytic formula for the two-loop QCD correction of the decay H --> 2 gamma is presented. To evaluate all master integrals a `Risch-like&#39; algorithm was exploited.

Axelle Amon, Marc Lefranc

Although deterministic chaos has been predicted to occur in the triply resonant optical parametric oscillator (TROPO) fifteen years ago, experimental evidence of chaotic behavior in this system has been lacking so far, in marked contrast with most nonlinear systems, where chaos has been actively tracked and found. This situation is probably linked to the hig

S. F. Sanchez, C. R. Benn

The impact of astronomical research carried out by different countries has been compared by analysing the 1000 most-cited astronomy papers published 1991-8 (125 from each year). 61% of the citations are to papers with first authors at institutions in the USA, 11% in the UK, 5% in Germany, 4% in Canada, 3% in Italy and 3% in France. 17% are to papers with fir

Jennifer E. Scott, Gerard A. Kriss, Julia C. Lee, Nahum Arav

We present a study of the intrinsic X-ray and far-ultraviolet absorption in the Seyfert 1.5 galaxy Markarian 279 using simultaneous observations from the Chandra X-ray Observatory, the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope, and the Far Ultraviolet Spectroscopic Explorer (FUSE). We also present FUSE observations made at three

D. Watson, J. Hjorth, A. Levan, P. Jakobsson

GRB031203 was observed by XMM-Newton twice, first with an observation beginning 6 hours after the burst, and again after 3 days. The afterglow had average 0.2-10.0keV fluxes for the first and second observations of 4.2+/-0.1x10^-13 and 1.8+/-0.1x10^-13 erg/cm^2/s respectively, decaying very slowly according to a power-law with an index of -0.55+/-0.05. The p

Naoki Sasakura

I construct field theory on an evolving fuzzy two-sphere, which is based on the idea of evolving non-commutative worlds of the previous paper. The equations of motion are similar to the one that can be obtained by dropping the time-derivative term of the equation derived some time ago by Banks, Peskin and Susskind for pure-into-mixed-state evolutions. The eq

Adebisi Agboola, Benjamin Howard

We study the Iwasawa theory of a CM elliptic curve $E$ in the anticyclotomic $\mathbf{Z}_p$-extension $D_\infty$ of the CM field $K$, where $p$ is a prime of good, supersingular reduction for $E$. Our main result yields an asymptotic formula for the corank of the $p$-primary Selmer group of $E$ along the extension $D_\infty/K$.

B. Aoun, M. Tarifi

We first give a brief overview over quantum computing, quantum key distribution (QKD), a practical architecture that integrates (QKD) in current internet security architectures, and aspects of network security. We introduce the concept of quantum contracts inspired from game theory. Finally, we introduce the basic architecture of the quantum internet and pre

Andrei Khrennikov

We present a new variant of the Växjö interpretation: contextualistic statistical realistic. Basic ideas of the Växjö interpretation-2001 are essentially clarified. We also discuss applications to biology, psychology, sociology, economy,...

Ugo Boscain, Gregoire Charlot

We consider an optimal control problem describing a laser-induced population transfer on a $n$-level quantum system. For a convex cost depending only on the moduli of controls (i.e. the lasers intensities), we prove that there always exists a minimizer in resonance. This permits to justify some strategies used in experimental physics. It is also quite import

C. Vrejoiu

A procedure to teach Electrodynamics independently of unit systems is presented and compared with some of those given in physics literature.

Marcel Ausloos

Various aspects of modern statistical physics and meteorology can be tied together. The historical importance of the University of Wroclaw in the field of meteorology is first pointed out. Next, some basic difference about time and space scales between meteorology and climatology is outlined. The nature and role of clouds both from a geometric and thermal po

Georg Essl

This paper discusses aspects of the second order hyperbolic partial differential equation associated with the ideal lossless string under tension and it&#39;s relationship to two discrete models. These models are finite differencing in the time domain and digital waveguide models. It is known from the theory of partial differential operators that in general

A. S. Siver, V. V. Ezhela

With the help of special program package PAREVAL designed in {\sl Mathematica} system we reproduce values of basic fundamental physical constants obtained by NIST and recommended by CODATA for international usage since 1998. In our adjustment we use the input data and methods published by NIST in 1998. It is shown, that the detected earlier inaccuracy of pub

A. Drago, S. Esposito

After a quick historical account of the introduction of the group-theoretical description of Quantum Mechanics in terms of symmetries, as proposed by Weyl, we examine some unpublished papers by Ettore Majorana. Remarkable results achieved by him in frontier research topics as well as in physics teaching point out that the Italian physicist can be well consid

Petr A. Skovorodko

Semi-empirical procedure of obtaining the boundary conditions for strong evaporation of a polyatomic gas from a plane surface is proposed. The procedure is based on specifying the dependencies of specific momentum and enthalpy of the flow from the gas flow rate. The latter are derived from the analysis of the available data concerning the evaporation of poly

M. S. Safronova, Charles W. Clark

Electric-dipole matrix elements for 6p-nd, n=5, 6, 7 transitions in cesium are calculated using a relativistic all-order method. The resulting matrix elements are used to evaluate 5d lifetimes and 6p polarizabilities. The data are compared with experimental lifetime and polarizability measurements made by different groups. Domination of the 6p scalar polariz

Yu. V. Kharlov, V. L. Korotkikh

We study the peripheral ion collisions at LHC energies in which a nucleus is excited to the discrete state and then emits $γ$-rays. Large nuclear Lorenz factor allows to observe the high energy photons up to a few ten GeV and in the region of angles of a few hundred micro-radians around the beam direction. These photons can be used for tagging the events wit

K. Hagino, M. Dasgupta, D. J. Hinde

We develop a three body classical trajectory Monte Carlo (CTMC) method to dicsuss the effect of the breakup process on heavy-ion fusion reactions induced by weakly bound nuclei. This method follows the classical trajectories of breakup fragments after the breakup takes place, and thus provides an unambiguous separation between complete and incomplete fusion

B. K. Patra, V. J. Menon

We revisit the standard treatment [Xu, Kharzeev, Satz and Wang, Phys. Rev. C {\bf 53}, 3051 (1996)] of $J/ψ$ suppression due to gluonic bombardment in an equilibrating quark-gluon plasma. Effects arising from gluon fugacity, relative $g-ψ$ flux, and $ψ$ meson formation time are correctly incorporated in the formulation of the gluon number density, velocity-w

A. Yu. Voronin, O. D. Dalkarov

We suggest a regular potential model of $N\bar{N}$ interaction without any cut-off. The effect of singular terms of OBE potential, modified by annihilation is shown to be repulsive. The experimental data for S- and P-wave scattering lengths are well reproduced.

L. Goldin, B. Yerozolimsky

Results of a study of the possibilities to reduce the low amplitude &#34;tail&#34; of the response characteristic of various electron detectors are presented. The main reason of such attribute of all detectors used in electron epectrometry is the energy of several hundreds KeV taken by the backscattered electrons. A simple method of rejecting the events when