October 1999 arXiv papers — page 7

R. Luusalo, A. Husmann, J. Kopu, P. J. Hakonen

We have investigated spreading of superfluid $^{4}$He on top of polished MgF$_2$ and evaporated SiO$_{2}$ substrates. Our results show strongly varying contact angles of 0 - 15 mrad on the evaporated layers. According to our theoretical calculations, these contact angles can be explained by a spatially varying distribution of vortex lines, the unpinning velo

Xiao-Guang Wang, Shao-Hua Pan, Guo-Zhen Yang

Within the framework of mean field theory, we examine the phase transitions in Ising magnetic films and superlattices. By transfer matrix method, we derive two general nonlinear equations for phase transition temperatures of Ising magnetic films and superlattices, respectively. The equations can be applied to the films and superlattices with arbitrary exchan

Robert Shrock, Shan-Ho Tsai

The q-state Potts antiferromagnet on a lattice $Λ$ exhibits nonzero ground state entropy $S_0=k_B \ln W$ for sufficiently large q and hence is an exception to the third law of thermodynamics. An outstanding challenge has been the calculation of W(sq,q) on the square (sq) lattice. We present here an exact calculation of W on an infinite-length cyclic strip of

X. Nie, E. Ben-Naim, S. Y. Chen

We study statistical properties of vibrated granular monolayers using molecular dynamics simulations. We show that at high excitation strengths, the system is in a gas state, particle motion is isotropic, and the velocity distributions are Gaussian. As the vibration strength is lowered the system's dimensionality is reduced from three to two. Below a cri

S. A. Stern, W. B. McKinnon

Neptune's largest satellite, Triton, is one of the most fascinating and enigmatic bodies in the solar system. Among its numerous interesting traits, Triton appears to have far fewer craters than would be expected if its surface was primordial. Here we combine the best available crater count data for Triton with improved estimates of impact rates by inclu

M. Revnivtsev, M. Gilfanov, E. Churazov

The properties of X-ray Nova XTE J1755-324, observed with RXTE and GRANAT observatories in 1997 are reported. The lightcurve of the source was typical for X-ray Novae, except for somewhat shorter decay time scale and the time elapsed between primary and subsequent secondary and tertiary outbursts. At the peak of the lightcurve the source had two-component sp

Guifre Vidal, Daniel Jonathan, M. A. Nielsen

We analyze approximate transformations of pure entangled quantum states by local operations and classical communication, finding explicit conversion strategies which optimize the fidelity of transformation. These results allow us to determine the most faithful teleportation strategy via an initially shared partially entangled pure state. They also show that

Alan R. White

Reggeized gluon interactions due to a single quark loop are studied in the full triple-regge limit and in closely related helicity-flip helicity-pole limits. Triangle diagram reggeon interactions are generated that include local axial-vector effective vertices. It is shown that the massless quark triangle anomaly is present as a chirality-violating infra-red

Xiao-Guang Wang, Hong-Chen Fu

We introduce new kinds of states of quantized radiation fields, which are the superpositions of negative binomial states. They exhibit remarkable non-classical properties and reduce to Schrödinger cat states in a certain limit. The algebras involved in the even and odd negative binomial states turn out to be generally deformed oscillator algebras. It is foun

Kur. R. Myrzakul, R. Myrzakulov

Some aspects of the relation between differential geometry of curves and surfaces and multidimensional soliton equations is discussed. The connection between multidimensional soliton equations and Self-dual Yang-Mills equation is studied.

Bin Wang, Elcio Abdalla

The cosmic holographic principle suggested by Fischler and Susskind has been examined in (2+1)-dimensional cosmological models. Analogously to the (3+1)-dimensional counterpart, the holographic principle is satisfied in all flat and open universes. For (2+1)-dimensional closed universes the holographic principle cannot be realized in general. The principle c

A. V. Belitsky, D. Müller, L. Niedermeier, A. Schäfer

We discuss possibilities of measurement of deeply virtual Compton scattering amplitudes via different asymmetries in order to access the underlying skewed parton distributions. Perturbative one-loop coefficient functions and two-loop evolution kernels, calculated recently by a tentative use of residual conformal symmetry of QCD, are used for a model dependen

Yasuhiro Okada

Effects of supersymmetric particles may appear in various low energy experiments through loop diagrams. We discuss various flavor changing neutral current processes, the muon anomalous magnetic moment and lepton flavor violation in the context of the supergravity model. In particular the $B^0$-$\ol{B}^0$ mixing and the muon anomalous magnetic moment are revi

E. N. Glass, J. P. Krisch

We develop some classical descriptions for processes in the Schwarzschild string atmosphere. These processes suggest relationships between macroscopic and microscopic scales. The classical descriptions developed in this essay highlight the fundamental quantum nature of the Schwarzschild atmospheric processes.

Atsushi Fujii, Kentaro Inui, Takenobu Tokunaga, Hozumi Tanaka

This paper proposes an efficient example sampling method for example-based word sense disambiguation systems. To construct a database of practical size, a considerable overhead for manual sense disambiguation (overhead for supervision) is required. In addition, the time complexity of searching a large-sized database poses a considerable problem (overhead for

B. M. Roehner

During a speculative episode the price of an item jumps from an initial level p_1 to a peak level p_2 before more or less returning to level p_1. The ratio p_2/p_1 is referred to as the amplitude A of the peak. This paper shows that for a given market the peak amplitude is a linear function of the logarithm of the price at the beginning of the speculative ep

Giorgio Parisi

In this talk I present some of the recent theoretical results that have been obtained on glassy systems like spin glasses or structural glasses. The physical principles at the basis of the theory are explained in a simple language (without using replicas) and the results are compared with large scale numerical simulations. Finally we introduce the generalize

S. Lubeck

We reconsider the moment analysis of the Bak-Tang-Wiesenfeld and the Manna sandpile model in two and three dimensions. In contrast to recently performed investigations our analysis turns out that the models are characterized by different scaling behavior, i.e., they belong to different universality classes.

See-Hun Yang, S. -J. Oh, Hyeong-Do Kim, Ran-Ju Jung

Resonant photoemission (RPES) at the Ce 3d -> 4f threshold has been performed for alpha-like compound CeNi_2 with extremely high energy resolution (full width at half maximum < 0.2 eV) to obtain bulk-sensitive 4f spectral weight. The on-resonance spectrum shows a sharp resolution-limited peak near the Fermi energy which can be assigned to the tail of the Kon

Karyn Le Hur

We study the Kondo effect in two crossed Luttinger liquids, using Boundary Conformal Field Theory. We predict two types of critical behaviors: either a two-channel Kondo fixed point with a nonuniversal Wilson ratio, or a new theory with an anomalous response identical to that found by Furusaki and Nagaosa (for the Kondo effect in a single Luttinger liquid).

Jose A. Font, Jose M. Ibanez, Philippos Papadopoulos

We have studied numerically the so-called Bondi-Hoyle (wind) accretion on to a rotating (Kerr) black hole in general relativity. We have used the Kerr-Schild form of the Kerr metric, free of coordinate singularities at the black hole horizon. The `test-fluid&#39; approximation has been adopted, assuming no dynamical evolution of the gravitational field. We h

N. G. Guseva, Y. I. Izotov, T. X. Thuan

We analyze long-slit spectral observations of 39 Wolf-Rayet (WR) galaxies with heavy element mass fraction ranging over 2 orders of magnitude, from Zsun/50 to 2Zsun. Nearly all galaxies in our sample show broad WR emission in the blue region of the spectrum (the blue bump) consisting of an unresolved blend of N III 4640, C III 4650, C IV 4658 and He II 4686

SLD Collaboration

Based on a sample of approximately 500,000 hadronic Z0 decays accumulated between 1993 and 1998, the SLD experiment has set limits on 24 fully charged two-body and quasi two-body exclusive charmless hadronic decays of B+, B0, and B0_s mesons. The precise tracking capabilities of the SLD detector provided for the efficient reduction of combinatoric background

B. Grzadkowski, J. F. Gunion

We explore the possibility that the Kaluza-Klein graviton states induce electroweak symmetry breaking. We also demonstrate that electroweak symmetry breaking could have a large impact on KK phenomenology.

S. Chaudhuri, Y. Chen, E. Novak

We give a path integral prescription for the pair correlation function of Wilson loops lying in the worldvolume of Dbranes in the bosonic open and closed string theory. The results can be applied both in ordinary flat spacetime in the critical dimension d or in the presence of a generic background for the Liouville field. We compute the potential between hea

Richard Easther, Matthew Parry

We investigate the possibility that nonlinear gravitational effects influence the preheating era after inflation. Our work is based on numerical solutions of the inhomogeneous Einstein field equations, and is free of perturbative approximations. The one restriction we impose is to limit the inhomogeneity to a single spatial direction. We compare our results

Soon-Tae Hong, Young-Jai Park

We newly apply the Batalin, Fradkin and Tyutin (BFT) formalism to the SU(3) flavor Skyrmion model to investigate the Weyl ordering correction to the structure of the hyperfine splittings of strange baryons. On the other hand, the Berry phases and Casimir effects are also discussed.

M. Revnivtsev, M. Gilfanov, E. Churazov

We analyze RXTE/PCA observations of GX339-4 in the low spectral state from 1996--1997 and show that the pattern of its spectral and temporal variability is nearly identical to that of Cyg X-1. In particular, a tight correlation exists between the QPO centroid frequency and the spectral parameters. An increase of the QPO centroid frequency is accompanied with

Sheldon Katz, Albrecht Klemm, Cumrun Vafa

We consider M-theory compactification on Calabi-Yau threefolds. The recently discovered connection between the BPS states of wrapped M2 branes and the topological string amplitudes on the threefold is used both as a tool to compute topological string amplitudes at higher genera as well as to unravel the degeneracies and quantum numbers of BPS states. Moduli

Norbert Lütkenhaus

I prove the security of quantum key distribution against individual attacks for realistic signals sources, including weak coherent pulses and downconversion sources. The proof applies to the BB84 protocol with the standard detection scheme (no strong reference pulse). I obtain a formula for the secure bit rate per time slot of an experimental setup which can

M. Beyer, C. Kuhrts, G. Roepke, P. D. Danielewicz

We address the formation of correlations in a general nonequilibrium situation. As an example we calculate the formation of light composite particles in a heavy ion collision. In particular we study the formation of deuterons via three-body reactions in some detail. To calculate the relevant reaction rates we solve the Faddeev equation which is consistently

M. Y. Simmons, A. R. Hamilton, M. Pepper, E. H. Linfield

A detailed investigation of the metallic behaviour in high quality GaAs-AlGaAs two dimensional hole systems reveals the presence of quantum corrections to the resistivity at low temperatures. Despite the low density ($r_{s}>10$) and high quality of these systems, both weak localisation (observed via negative magnetoresistance) and weak hole-hole interactions

I. Brevik, H. B. Sandvik

Magnetohydrodynamic (MHD) waves are analysed in the early Universe, in the inflationary era, assuming the Universe to be filled with a nonviscous fluid of the Zel&#39;dovich type ($p=ρ$) in a metric of the de Sitter form. A spatially uniform, time dependent, magnetic field ${\bf B_0}$ is assumed to be present. The Einstein equations are first solved to give

May Chiao, R. W. Hill, Christian Lupien, Louis Taillefer

A residual linear term is observed in the thermal conductivity of optimally-doped Bi-2212 at very low temperatures whose magnitude is in excellent agreement with the value expected from Fermi-liquid theory and the d-wave energy spectrum measured by photoemission spectroscopy, with no adjustable parameters. This solid basis allows us to make a quantitative an

Riccardo Scarpa, C. Megan Urry

The energy budget of all known optical jets is discussed. It is found that to power the extended radio lobes of radio galaxies, the jet bulk motion on kpc scales must be relativistic, on average. Based on various constraints, a ``most probable&#39;&#39; region centered around bulk Lorentz factor ~7.5 and jet inclination \~20 degrees is found. Because of the

Bodo Geyer, Dmitry Gitman, Ilya Shapiro

Starting from the Dirac equation in external electromagnetic and torsion fields we derive a path integral representation for the corresponding propagator. An effective action, which appears in the representation, is interpreted as a pseudoclassical action for a spinning particle. It is just a generalization of Berezin-Marinov action to the background under c

M. Copelli, C. Van den Broeck

We study a model of unsupervised learning where the real-valued data vectors are isotropically distributed, except for a single symmetry breaking binary direction $\bm{B}\in\{-1,+1\}^{N}$, onto which the projections have a Gaussian distribution. We show that a candidate vector $\bm{J}$ undergoing Gibbs learning in this discrete space, approaches the perfect

Marcos Jardim

We present the Nahm transform of the doubly-periodic instantons introduced in math.DG/9909069, converting them into certain meromorphic solutions of Hitchin&#39;s equations over an elliptic curve.

Friedemann Brandt, Joan Simon, Ulrich Theis

We construct non-standard interactions between exterior form gauge fields by gauging a particular global symmetry of the Einstein-Maxwell action for such fields. Furthermore we discuss generalizations of such interactions by adding couplings to gravitational Chern-Simons forms and to fields arising through dimensional reduction. The construction uses an appr

Allen C. Hirshfeld, Thomas Schwarzweller

We apply the antifield quantization method of Batalin and Vilkovisky to the calculation of the path integral for the Poisson-Sigma model in a general gauge. For a linear Poisson structure the model reduces to a nonabelian gauge theory, and we obtain the formula for the partition function of two-dimensional Yang-Mills theory for closed two-dimensional manifol

R. Denk, R. Mennicken, L. Volevich

In this paper operator pencils $A(x,D,\lambda)$ are investigated which depend polynomially on the parameter $\lambda$ and act on a manifold with boundary. The operator A is assumed to satisfy the condition of N-ellipticity with parameter which is an ellipticity condition formulated with the use of the Newton polygon. We consider general boundary operators $B

Jean-Pierre Demailly, János Kollár

We introduce complex singularity exponents of plurisubharmonic functions and prove a general semi-continuity result for them. This concept contains as a special case several similar concepts which have been considered e.g. by Arnold and Varchenko, mostly for the study of hypersurface singularities. The plurisubharmonic version is somehow based on a reduction

M. Hennion, F. Moussa, J. Rodriguez-Carvajal, L. Pinsard

Elastic and inelastic neutron scattering experiments have been performed in a La$_{0.94}$Sr$_{0.06}$MnO$_3$ untwinned crystal, which exhibits an antiferromagnetic canted magnetic structure with ferromagnetic layers. The elastic small q scattering exhibits a modulation with an anisotropic q-dependence. It can be pictured by ferromagnetic inhomogeneities or po

J. A. K. Freire, A. Matulis, F. M. Peeters, V. N. Freire

The effective Hamiltonian describing the motion of an exciton in an external non-homogeneous magnetic field is derived. The magnetic field plays the role of an effective potential for the exciton motion, results into an increment of the exciton mass and modifies the exciton kinetic energy operator. In contrast to the homogeneous field case, the exciton in a

Ludwig Hartmann, Igor Goychuk, Milena Grifoni, Peter Hanggi

In the regime of weak bath coupling and low temperature we demonstrate numerically for the spin-boson dynamics the equivalence between two widely used but seemingly different roads of approximation, namely the path integral approach and the Bloch-Redfield theory. The excellent agreement between these two methods is corroborated by a novel efficient analytica

Igor Goychuk, Peter Hanggi

We identify a unifying measure for stochastic resonance (SR) in voltage dependent ion channels which comprises periodic (conventional), aperiodic and nonstationary SR. Within a simplest setting, the gating dynamics is governed by two-state conductance fluctuations, which switch at random time points between two values. The corresponding continuous time point

P. Malits, A. Kaplunovsky, I. D. Vagner, P. Wyder

The energy spectrum of an electron confined to an arbitrary surface of revolution in an external magnetic field, parallel to the symmetry axis, is studied analitycally and numerically. The problem is reduced via conformal mapping to one on the surface of a sphere. The case of a spheroid is considered in details, and the dependence on parameters is discussed.

An Min Wang

Making use of an universal quantum network -- QCPU proposed by me\upcite{My1}, it is obtained that the whole quantum network which can implement some the known quantum algorithms including Deutsch algorithm, quantum Fourier transformation, Shor&#39;s algorithm and Grover&#39;s algorithm.

An Min Wang

Making use of an universal quantum network or QCPU proposed by me [6], some special quantum networks for simulating some quantum systems are given out. Specially, it is obtained that the quantum network for the time evolution operator which can simulate, in general, Schrödinger equation.

Kor Van Hoof

We present the action for a self-dual tensor in six dimensions, coupled to a (2,0) conformal supergravity background. This action gives rise to the expected equations of motion. An alternative look upon one of the gauge symmetries clarifies its role in the supersymmetry transformation rules and the realisation of the algebra.

Tetsuya Shiromizu, Kei-ichi Maeda, Misao Sasaki

We carefully investigate the gravitational equations of the brane world, in which all the matter forces except gravity are confined on the 3-brane in a 5-dimensional spacetime with $Z_2$ symmetry. We derive the effective gravitational equations on the brane, which reduce to the conventional Einstein equations in the low energy limit. {}From our general argum

Gerard Gilmore, Xavier Hernandez, David Valls-Gabaud

Late accretion models for formation of the Galactic halo require that many Galactic satellite galaxies have been cannibalised into the halo field. Comparison of the metallicity and age distribution function of stars in the surviving satellites with the apparently exclusively old stars in the field halo can constrain the importance of any such process. We hav

Hiroshi Shimahara, Yasumasa Hasegawa, Mahito Kohmoto

A reduction of the density of states near the Fermi energy in the normal state (pseudogap) of high-temperature oxide superconductors is examined on the basis of the two-dimensional tight-binding model with effective interactions due to antiferromagnetic fluctuations. By using antiferromagnetic correlation lengths which are phenomenologically assumed, the dop

J. Sato

We consider possibilities of observing CP-violation effects in neutrino oscillation experiments with low energy ($\sim$ several hundreds MeV).

Johannes Wiedersich, Sergei V. Adichtchev, Ernst R&#34;ossler

Precise low-frequency light scattering experiments on silica glass are presented, covering a broad temperature and frequency range (9 GHz < ν< 2 THz). For the first time the spectral shape of relaxations is observed over more than one decade in frequency. The spectra show a power-law low-frequency wing of the relaxational part of the spectrum with an exponen

C. B. Stagarescu, X. Su, D. E. Eastman, K. N. Altmann

The orbital character, orientation, and magnetic polarization of the O 2$p$ unoccupied states near the Fermi level ($E_F$) in CrO$_2$ was determined using polarization-dependent X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) from high-quality, single-crystal films. A sharp peak observed just above $E_F$ is excited only by th

Jeffrey Bub, Rob Clifton, Sheldon Goldstein

We show that the Bub-Clifton uniqueness theorem for &#39;no collapse&#39; interpretations of quantum mechanics (Studies in the History and Philosophy of Modern Physics 27, 181-219 (1996)) can be proved without the &#39;weak separability&#39; assumption.

Jeffrey Bub

I show how quantum mechanics, like the theory of relativity, can be understood as a &#39;principle theory&#39; in Einstein&#39;s sense, and I use this notion to explore the approach to the problem of interpretation developed in my book Interpreting the Quantum World (Cambridge: Cambridge University Press, 1999).

H. Bechmann-Pasquinucci, W. Tittel

Like all of quantum information theory, quantum cryptography is traditionally based on two level quantum systems. In this letter, a new protocol for quantum key distribution based on higher dimensional systems is presented. An experimental realization using an interferometric setup is also proposed. Analyzing this protocol from the practical side, one finds

M. D. Lukin, A. Imamoglu

Two light pulses propagating with ultra-slow group velocities in a coherently prepared atomic gas exhibit dissipation-free nonlinear coupling of an unprecedented strength. This enables a single-photon pulse to coherently control or manipulate the quantum state of the other. Processes of this kind result in generation of entangled states of radiation field an

J. Rehacek, Z. Hradil, M. Dusek, O. Haderka

An experimental comparison of several operational phase concepts is presented. In particular, it is shown that statistically motivated evaluation of experimental data may lead to a significant improvement in phase fitting upon the conventional Noh, Fouge&#39;res and Mandel procedure. The analysis is extended to the asymptotic limit of large intensities, wher

Sameen Ahmed Khan, Modesto Pusterla

In recent times there has been a renewed interest in the force experienced by a charged-particle with anomalous magnetic moment in the presence of external fields. In this paper we address the basic question of the force experienced by a spin-1/2 point-like charged-particle with magnetic and electric moments in the presence of space-and time-dependent extern

S. N. Ahmed, H. -J. Besch, A. H. Walenta, N. Pavel

A single channel, high precision ionization chamber has been built for monitoring the relative intensity of X-rays in the energy range above 5 keV. It can be used in experiments, such as EXAFS, where simultaneous high precision monitoring of the relative intensity during the actual experiment is required. In this paper the construction of the chamber and its

A. Fabrocini, F. Arias de Saavedra, G. P. Co&#39;

We review the latest variational calculations of the ground state properties of doubly closed shell nuclei, from $^{12}$C to $^{208}$Pb, with semirealistic and realistic two- and three-nucleon interactions. The studies are carried on within the framework of the correlated basis function theory and integral equations technique, with state dependent correlatio

B. Lenkeit, CERES-Collaboration

During the 1996 lead run time, CERES has accumulated 42 million events, corresponding to a factor of 5 more statistics than in 1995 and 2.5 million events of a special photon-run. We report on the results of the low-mass e$^+$e$^-$-pair analysis. Since the most critical item is the poor signal-to-background ratio we also discuss the understanding of this bac

Thomas Hupfer, Hajo Leschke, Simone Warzel

For a charged quantum particle in the Euclidean plane subject to a perpendicular constant magnetic field and repulsive impurities, randomly distributed according to Poisson&#39;s law, we determine the leading low-energy fall-off of the integrated density of states in case the single-impurity potential has either super-Gaussian or regular sub-Gaussian long-di

Masato Kuwata, Jaap Top

We study the surface arising from the diophantine equation $m^3+(m+1)^3+...+(m+k-1)^3=l^2$. It turns out that this is a $K3$ surface with Picard number 20. We stduy its aritmetic properties in detail. We construct elliptic fibrations on it, and we find a parametric solution to the original equation. Also, we determine the Hasse-Weil zeta function of the surf

Lars Hesselholt, Ib Madsen

The authors establish a connection between the Quillen K-theory of certain local fields and the de Rham-Witt complex of their rings of integers with logarithmic poles at the maximal ideal. They consider fields K that are complete discrete valuation fields of characteristic zero with perfect residue fields k of characteristic p > 2. They evaluate the K-theory

N. J. Kalton, G. Lancien

We give a negative solution to the problem of the $L^p$-maximal regularity on various classes of Banach spaces including $L^q$-spaces with $1<q \neq 2<+\infty$.

Daniel C. Cohen

We prove similar theorems concerning the structure of bundles involving complements of fiber-type hyperplane arrangements and orbit configuration spaces. These results facilitate analysis of the fundamental groups of these spaces, which may be viewed as generalizations of the Artin pure braid group. In particular, we resolve two disparate conjectures. We sho

Fabio Gavarini, Gilles Halbout

Let g be a quasitriangular Lie bialgebra over a field k of characteristic zero, and let g^* be its dual Lie bialgebra. We prove that the formal Poisson group F[[g^*]] is a braided Hopf algebra. More generally, we prove that if (U_h,R) is any quasitriangular QUEA, then (U_h&#39;, Ad(R)|_{U_h&#39; \otimes U_h&#39;}) --- where U_h&#39; is defined by Drinfeld --

Mina Aganagic, Andreas Karch

We show that there are two different dualities of two dimensional gauge theories with N=(2,2) supersymmetry. One is basically a consequence of 3d mirror symmetry. The non-linear sigma model with Calabi-Yau target space on the Higgs branch of the gauge theory is mapped into an equivalent non-linear sigma model on the Coulomb branch of the dual theory, realizi

Gabriel Lopes Cardoso, Bernard de Wit, Thomas Mohaupt

Modifications of the Bekenstein-Hawking area law for black holes are crucial in order to find agreement between the microscopic entropy based on state counting and the macroscopic entropy based on an effective field theory computation. We discuss this and related issues for the case of four-dimensional N=2 supersymmetric black holes. We also briefly comment

Tetsuya Shiromizu

We give a cosmological spinning multi-`black-hole&#39; solution in the Einstein-Maxwell-Dilaton-Axion theory with a positive cosmological constant. This solution is the cosmological dilatonic Israel-Wilson-Perjes solution and describes the collision of several spinning `black-holes&#39;.

Jerome P. Gauntlett

By analysing supersymmetry transformations we derive new BPS equations for the D=11 fivebrane propagating in flat space that involve the world-volume three-form. The equations generalise those of 2,3,4 and 5 dimensional special Lagrangian submanifolds and are relevant for describing membranes ending on these submanifolds.

Randy Lewis, Nader Mobed

The strange form factors of the proton are basic to an understanding of proton structure, and are presently the focus of many experiments. Before the strangeness effects can be extracted from data, it is necessary to calculate and remove effects due to isospin violation, which exist independently of the strange quark but which contribute nevertheless to the

A. Garcia, R. Huerta, G. Sanchez-Colon

We consider the hypothesis of a priori mixings in the mass eigenstates of mesons to obtain the |Delta I|=1/2 rule in K\toππ. The Hamiltonian responsible for the transition is the strong interacting one. The experimental data are described using the isospin symmetry relations between the strong coupling constants.

George T. Fleming

We present results from simulations of two flavor QCD thermodynamics at N_t=4 with domain wall fermions. In contrast to other lattice fermion formulations, domain wall fermions preserve the full chiral symmetry of the continuum at finite lattice spacing (up to terms exponentially small in an extra parameter). Just above the phase transition, we find that the

A. Garcia, R. Huerta, G. Sanchez-Colon, .

We show that the so-called parity-conserving amplitudes predicted in the a priori mixing scheme for non-leptonic and weak radiative decays of hyperons vanish in the strong-flavor symmetry limit.

Abdelhak Djouadi

I summarize the prospects for discovering and studying the properties of Higgs particles at future high-energy and high-luminosity $e^+e^-$ linear colliders. I will focus on the Higgs particle of the Standard Model and the Higgs bosons predicted by Supersymmetric theories.

C. Duprel, Th. Hadig, N. Kauer, M. Wobisch

We compare different next-to-leading order calculations of jet cross sections in deep-inelastic scattering as implemented in the programs DISASTER++, DISENT, JETVIP and MEPJET. In all phase space regions under study DISENT and DISASTER++ agree better than 2%. MEPJET shows systematic deviations of being typically 5-8% lower than the other programs. The JETVIP

F. Buccella, O. Pisanti

We review the status of a class of gauge unified models based on SO(10) group and discuss the main phenomenological implications of these models in particular for neutrino masses.

B. -J. Schaefer, O. Bohr, J. Wambach

Flow equations for an O(N)-symmetric effective potential are discussed and solved for the finite temperature case. The model is investigated at the critical point and critical exponents for various N are calculated.

Marco Aurelio Diaz

We report on the effect that one-loop radiative corrections to the chargino pair production cross section has on the determination of the fundamental parameters of the theory. We work in the context of electron-positron colliders with sqrt(s)=500 GeV. We conclude that the inclusion of these corrections is crucial in precision measurements, specially at large

A. D. Dolgov, S. H. Hansen, S. Pastor, D. V. Semikoz

The lepton asymmetry that could be generated in the early universe through oscillations of active to sterile neutrinos is calculated (almost) analytically for small mixing angles, sin 2θ< 10^{-2}. It is shown that for a mass squared difference, δm^2=-1 eV^2 it may rise at most by 6 orders of magnitude from the initial ``normal&#39;&#39; value of 10^{-10}, si

Nils A. Tornqvist

The lightest scalar and pseudoscalar nonets are discussed within the [A framework of the broken old UxU3 linear sigma model, and it is shown that already at the tree level this model works remarkably well predicting scalar masses and couplings not far from present experimental values, when all parameters are fixed from the pseudoscalar masses and decay const

Jan-e Alam, Sourav Sarkar, Pradip Roy, T. Hatsuda

The photon and dilepton emission rates from quark gluon plasma and hot hadronic matter have been evaluated. The in-medium modifications of the particles appearing in the internal loop of the self energy diagram are taken into account by using a phenomenological effective Lagrangian approach, Brown-Rho and Nambu scaling scenarios. We note that the in-medium e

Gongru Lu, Zhenjun Xiao, Hongkai Guo, Linxia Lü

The new contributions to the charmless B decay $B \to X_{s}η^{\prime}$ from the unit-charged technipions $P^{\pm}$ and $P^{\pm}_{8}$ are estimated. The technipions can provide a large enhancement to the inclusive branching ratio: $Br(B \to X_{s}η^{\prime}) \sim 7\times 10^{-4}$ for $m_{p1}=100GeV$ and $m_{p8}=250 \sim 350 GeV$ when the effect of QCD gluon an

M. Diehl, T. Gousset, B. Pire

We discuss two aspects of polarisation in hard exclusive meson production: the leading-twist selection rule for the meson helicity, and the different partial waves of a (pi pi)-pair which may or may not be due to the decay of a rho.

CDF Collaboration

We have searched for direct pair production of scalar top and scalar bottom quarks in 88 pb$^{-1}$ of $p\bar{p}$ collisions at $\sqrt{s}=1.8$ TeV with the CDF detector. We looked for events with a pair of heavy flavor jets and missing energy, consistent with scalar top quark decays to a charm quark and a neutralino, or scalar bottom quark decays to a bottom

L. G. Landsberg

Evidences for new baryon states with mass >1.8 GeV were obtained in the experiments of the SPHINX Collaboration in studying hyperon-kaon mass spectra in several proton diffractive reactions. The main result of these experiments is the observation of X(2000)->SIGMA K state with unusual dynamical features (narrow width, anomalously large branching ratios for t

H. Friedrich, J. Kannar

We relate Bondi systems near space-like infinity to another type of gauge conditions. While the former are based on null infinity, the latter are defined in terms of Einstein propagation, the conformal structure, and data on some Cauchy hypersurface. For a certain class of time symmetric space-times we study an expansion which allows us to determine the beha

Yoshiaki Ohkuwa

In order to study the &#34;problem of time&#34;, Rovelli proposed a model of a two harmonic oscillator system where one of the oscillators can be thought of as a &#39;clock&#39; for the other oscillator. In this paper we examine a model where the Hamiltonian is a difference between two harmonic oscillators, and we consider one of them which has the minus sig

R. Baldoni, F. Quaglia, M. Raynal

Whether it is for audit or for recovery purposes, data checkpointing is an important problem of distributed database systems. Actually, transactions establish dependence relations on data checkpoints taken by data object managers. So, given an arbitrary set of data checkpoints (including at least a single data checkpoint from a data manager, and at most a da

A. Lipowski, D. Johnston

Using Monte Carlo simulations we study cooling-rate effects in a three-dimensional Ising model with four-spin interaction. During coarsening, this model develops growing energy barriers which at low temperature lead to very slow dynamics. We show that the characteristic zero-temperature length increases very slowly with the inverse cooling rate, similarly to

Hudong Chen, Bruce M. Boghosian, Peter V. Coveney

A lattice Boltzmann model for amphiphilic fluid dynamics is presented. It is a ternary model, in that it conserves mass separately for each chemical species present (water, oil, amphiphile), and it maintains an orientational degree of freedom for the amphiphilic species. Moreover, it models fluid interactions at the microscopic level by introducing self-cons

Naoki Kawashima

The two-dimensional Edwards-Anderson model with Gaussian bond distribution is investigated at T=0 with a numerical method. Droplet excitations are directly observed. It turns out that the averaged volume of droplets is proportional to l^D with D = 1.80(2) where l is the spanning length of droplets, revealing their fractal nature. The exponent characterizing

Marcia C. Barbosa, Markus Deserno, Christian Holm

Based on a Debye-Hueckel approach to the one-component plasma we propose a new free energy for incorporating ionic correlations into Poisson-Boltzmann like theories. Its derivation employs the exclusion of the charged background in the vicinity of the central ion, thereby yielding a thermodynamically stable free energy density, applicable within a local dens

Yan V. Fyodorov

Disordered $RL-C$ networks are known to be an adequate model for describing fluctuations of electric fields in a random metal-dielectric composite. We show that under appropriate conditions the statistical properties of such a system can be studied in the framework of the Efetov&#39;s non-linear $σ-$ model. This fact provides a direct link to the theory of A

A. Sedeki, L. G. Caron, C. Bourbonnais

We reexamine the putative Peierls transition in a (5,5) metallic nanotube. We show that the conduction electrons at the Fermi level do not couple to the longitudinal acoustic phonon but rather to a folded-in graphene zone edge phonon having the proper Kekule modulation symmetry. The calculation for the mean-field transition temperature gives 15 K, a value co