January 1998 arXiv papers — page 16

Stephan Dürr

A proposal is presented for simulating an improvement on quenched QCD with dynamical fermions which interact with the gluon configuration only via the topological index of the latter. Strengths and shortcomings of the method are discussed and it is argued that the approximation - though being crude - shares some qualitative aspects of full QCD which relate t

Andrei V. Gruzinov, John N. Bahcall

We evaluate the effect of electrostatic screening by ions and electrons on low-Z thermonuclear reactions in the sun. We use a mean field formalism and calculate the electron density of the screening cloud using the appropriate density matrix equation of quantum statistical mechanics. Because of well understood physical effects that are included for the first

W. T. Buttler, R. J. Hughes, P. G. Kwiat, G. G. Luther

A working free-space quantum key distribution (QKD) system has been developed and tested over a 205-m indoor optical path at Los Alamos National Laboratory under fluorescent lighting conditions. Results show that free-space QKD can provide secure real-time key distribution between parties who have a need to communicate secretly.

Nicolas Gisin

Perfect Quantum Cloning Machines (QCM) would allow to use quantum nonlocality for arbitrary fast signaling. However perfect QCM cannot exist. We derive a bound on the fidelity of QCM compatible with the no-signaling constraint. This bound equals the fidelity of the Bužek-Hillery QCM.

M. E. Garcia, Ll. Serra, F. Garcias, K. H. Bennemann

The life-times due to Auger-electron emission for a hole on a deep electronic shell of neutral and charged sodium clusters are studied for different sizes. We consider spherical clusters and calculate the Auger-transition probabilities using the energy levels and wave functions calculated in the Local-Density-Approximation (LDA). We obtain that Auger emissio

Klaus Geiger

There seems to be a general consensus now that a first glimpse of a QGP-like effect has become visible in the beautiful NA50 data on J/ψproduction and the `anomalous supression' phenomenon. On the other hand, it is still widely believed that the dynamics of heavy-ion collisions at CERN SPS energy is predominantly governed by soft, non-perturbative physic

E. Bauer

The transverse nuclear response to an electromagnetic probe which is limited to create (or destroyed) a particle-hole ($ph$) or delta-hole ($Δh$) pair is analyzed. Correlations of the random phase approximation (RPA) type and self energy insertions are considered. For RPA correlations we have developed a scheme which includes explicitly the $Δ$ and the excha

T. Rauscher, R. Bieber, H. Oberhummer, K. -L. Kratz

The prediction of cross sections for nuclei far off stability is crucial in the field of nuclear astrophysics. We calculate direct neutron capture on the even-even isotopes $^{124-145}$Sn and $^{208-238}$Pb with energy levels, masses, and nuclear density distributions taken from different nuclear-structure models. The utilized structure models are a Hartree-

William P. Thurston

This is the first in a series of papers showing that Haken manifolds have hyperbolic structures; this first was published, the second two have existed only in preprint form, and later preprints were never completed. This eprint is only an approximation to the published version, which is the definitive form for part I, and is provided for convenience only. Al

Feng Luo

Given a compact orientable surface $Σ$, let $\Cal S(Σ)$ be the set of isotopy classes of essential simple loops on $Σ$. We determine a complete set of relations for a function from $\Cal S(Σ)$ to $\bold Z$ to be a geometric intersection number function. As a consequence, we obtain explicit equations in $\bold R^{\Cal S(Σ)}$ and $P(\bold R^{\Cal S(Σ)})$ defin

Bruno Kahn

Let p be a prime number. We give a conjecture of a sheaf-theoretic nature which is equivalent to the strong form of the Tate conjecture for smooth, projective varieties X over F_p: for all n>0, the order of pole of the Hasse-Weil zeta function of X at s=n equals the rank of the group of algebraic cycles of codimension n modulo numerical equivalence. Our main

Doron Zeilberger

H. N. V. Temperley's method for counting vertically convex polyominoes is modified, generalized, and most importantly, programmed (in Maple).

Bernhard Leeb, Peter Scott

We prove the existence of a geometric characteristic submanifold for non-positively curved manifolds of any dimension greater than or equal to three. In dimension three, our result is a geometric version of the topological characteristic submanifold theorem due to Jaco, Shalen and Johannson.

Lee Smolin

A connection between non-perturbative formulations of quantum gravity and perturbative string theory is exhibited, based on a formulation of the non-perturbative dynamics due to Markopoulou. In this formulation the dynamics of spin network states and their generalizations is described in terms of histories which have discrete analogues of the causal structur

V. E. R. Lemes, C. Linhares de Jesus, S. P. Sorella, L. C. Q. Vilar

Three dimensional Yang-Mills gauge theories in the presence of the Chern-Simons action are seen as being generated by the pure topological Chern-Simons term through nonlinear covariant redefinitions of the gauge field

F. M. Steffens

We investigate an alternative to the DGLAP evolution of structure functions through the use of Fixed Order Perturbation Theory. Remarkable agreement between the two methods are found in the polarized sector for a wide $x$, $Q^2$ region. However, for the unpolarized sector the agreement is poorer.

George Siopsis

We study the effects of gluon interference in the production and semi-leptonic decay of a t-tbar pair above threshold at the Next Linear Collider (NLC). We calculate all matrix elements to next-to-leading order and use the resulting expressions for the development of a Monte Carlo event generator. Our results show effects at the level of 10% in differential

Y. Matiounine, J. Smith, W. L. van Neerven

We present the two-loop corrected operator matrix elements calculated in N-dimensional regularization up to the finite terms which survive in the limit $ε= N - 4 \to 0 $. The anomalous dimensions of the local operators have been previously extracted from the pole terms and determine the scale evolution of the deep inelastic structure functions measured in un

Andrew Yates, Wojciech H. Zurek

We investigate the dynamics of second order phase transitions in two dimensions, breaking a gauged U(1) symmetry. Using numerical simulations, we show that the density of topological defects formed scales with the quench timescale $τ_Q$ as $n \sim τ_Q^{-1/2}$ when the dynamics is overdamped at the instant when the freezeout of thermal fluctuations takes plac

V. M. Braun

A short introduction is given to the method of light-cone sum rules, their theoretical background and main modifications. The discussion is concentrated but not restricted to the applications to heavy quark decays.

Pengfei Zhuang, Ulrich Heinz

We investigate in the equal-time formalism the derivation and truncation of infinite hierarchies of equations of motion for the energy moments of the covariant Wigner function. From these hierarchies we then extract kinetic equations for the physical distribution functions which are related to low-order energy moments, and show how to determine the higher or

M. Göckeler, R. Horsley, V. Linke, P. Rakow

We present new numerical results for the renormalized mass and coupling in non-compact lattice QED with staggered fermions. Implications for the continuum limit and the role of the Landau pole are discussed.

Stefan Spanier

The Crystal Barrel Collaboration observes scalar meson resonances in $\bar p p$ annihilation. Based on the measurements and partial wave analyses these are candidates for the $^3$P$_0$ groundstate nonet. The supernummerary $f_0(1500)$ resonance is identified as a scalar groundstate glueball. Important information for its characterization comes from the decay

R. Ben-David, representing the KTeV collaboration

The KTeV experiment is a fixed target experiment at Fermilab. Its primary goal is the search for direct CP violation in the decay of neutral kaons. Its current status and some preliminary results will be discussed.

Rajendran Raja, Alvin Tollestrup

The neutral Higgs boson is expected to have a mass in the region 90-150 GeV in various schemes within the Minimal Supersymmetric extension to the Standard Model. A first generation Muon Collider is uniquely suited to investigate the mass, width and decay modes of the Higgs boson, since the coupling of the Higgs to muons is expected to be strong enough for it

Beverly K. Berger

Spatially homogeneous but possibly anisotropic cosmologies have two main types of singularities: (1) asymptotically velocity term dominated (AVTD) - (reversing the time direction) the universe evolves to the singularity with fixed anisotropic collapse rates ; (2) Mixmaster-the anisotropic collapse rates change in a deterministicaly chaotic way. Much less is

E. R. Bezerra de Mello, V. B. Bezerra, Yu. V. Grats

We calculate the electromagnetic self-force on a stationary linear distribution of four-current in the spacetime of multiple cosmic strings. It is shown that if the current is infinitely thin and stretched along a line which is parallel to the strings the problem admits an explicit solution.

A. H. MacDonald

The three-dimensional electron-gas model has been a major focus for many-body theory applied to the electronic properties of metals and semiconductors. Because the model neglects band effects, whereas electronic systems are generally more strongly correlated in narrow band systems, it is most widely used to describe the qualitative physics of weakly correlat

H. Bucheli, O. S. Wagner, V. B. Geshkenbein, A. I. Larkin

Motivated by the problem of weak collective pinning of vortex lattices in high-temperature superconductors, we study the model system of a four-dimensional elastic manifold with N transverse degrees of freedom (4+N-model) in a quenched disorder environment. We assume the disorder to be weak and short-range correlated, and neglect thermal effects. Using a rea

G. Litak, A. M. Martin, B. L. Gyorffy, J. F. Annett

We apply the coherent potential approximation (CPA) to a simple model for disordered superconductors with d-wave pairing. We demonstrate that whilst the effectiveness of an electronic Van Hove singularity to enhance the transition temperature T$_c$ is reduced by disorder it is not eliminated. In fact we give a qualitative account of changes in the T$_c$ vs.

Giorgio Parisi

In off-equilibrium dynamics we define a dynamical correlation length which is proportional to the size of the region in which the atoms move in a correlated way. General arguments indicate that this dynamical correlation length diverges at large times in the glassy phase. Numerical simulations for binary mixtures point toward the correctness of this predicti

Ronald Fisch

Monte Carlo simulations have been used to study a discretized Heisenberg ferromagnet (FM) with random uniaxial single-site anisotropy on $L \times L \times L$ simple cubic lattices, for $L$ up to 64. The spin variable on each site is chosen from the twelve [110] directions. The random anisotropy has infinite strength and a random direction on a fraction $x$

D. Mihailovic, T. Mertelj, K. A. Mueller

Analysis of the a-b plane optical conductivity $σ_{ab}$ for both twinned and untwinned YBa$_{2}$Cu$_{3}$O$_{7-δ}$ as a function of temperature and doping shows that below a well defined temperature T*, a dip in the spectrum systematically appears separating the infrared charge excitation spectrum into two components with distinct energy scales. The change fr

Klaus Doll, Hermann Stoll

We extend previous work on alkali halides by calculations for the heavy-atom species RbF, RbCl, LiBr, NaBr, KBr, RbBr, LiI, NaI, KI, and RbI. Relativistic effects are included by means of energy-consistent pseudopotentials, correlations are treated at the coupled-cluster level. A striking deficiency of the Hartree-Fock approach are lattice constants deviatin

William H. Beere, James F. Annett

We examine the quasiparticle lifetime and spectral weight near the Fermi surface in the two-dimensional Hubbard model. We use the FLEX approximation to self-consistently generate the Matsubara Green's functions and then we analytically continue to the real axis to obtain the quasiparticle spectral functions. We compare the spectral functions found in the

M. Mezard

Talk presented at the International Conference on Mathematical Physics (Brisbane 1997). This is an introduction to recent work on the scaling and intermittency in forced Burgers turbulence. The mapping between Burgers' equation and the problem of a directed polymer in a random medium is used in order to study the fully developped turbulence in the limit

Christophe Chatelain, Bertrand Berche

The self-dual random-bond eight-state Potts model is studied numerically through large-scale Monte Carlo simulations using the Swendsen-Wang cluster flipping algorithm. We compute bulk and surface order parameters and susceptibilities and deduce the corresponding critical exponents at the random fixed point using standard finite-size scaling techniques. The

T. Nikuni, A. Griffin

Griffin, Wu and Stringari have derived the hydrodynamic equations of a trapped dilute Bose gas above the Bose-Einstein transition temperature. We give the extension which includes hydrodynamic damping, following the classic work of Uehling and Uhlenbeck based on the Chapman-Enskog procedure. Our final result is a closed equation for the velocity fluctuations

K. Bernlohr, W. Hofmann, G. Leffers, V. Matheis

Changes of the cosmic-ray mass composition at the `knee' of the cosmic-ray flux spectrum near 10^{15} eV energy are investigated using data from ten Cosmic Ray Tracking (CRT) detectors and the HEGRA air-shower array on La Palma, Canary Islands. The analysis is based on the angular distribution of muons in air showers. Results can be easily expressed in t

M. G. Allen, M. A. Dopita, Z. I. Tsvetanov

Optical diagnostic diagrams are frequently ambiguous as a test of the photoionization or fast shock models of the narrow line regions of active galaxies. Here, we present a set of UV line ratio diagrams which can discriminate between pure shock and photoionization modes of excitation, and to some extent, also discriminate shocks with ionized precursors from

M. Villar-Martin, C. N. Tadhunter, R. Morganti, N. E. Clark

We present optical and radio images, and long-slit spectra of the radio galaxy PKS 1932-464 (z=0.230). Our main goal is to determine whether the observed properties of the extended emission line nebulosity in this object show evidence for interactions between the radio jet and the extended ionized gas, or whether they can be explained in terms of the illumin

Jeremy S. Heyl, Lars Hernquist

RX J0720.4-3125 has recently been identified as a pulsating soft X-ray source in the ROSAT all-sky survey with a period of 8.391 s. Its spectrum is well characterized by a black-body with a temperature of $8 \times 10^5$ K. We propose that the radiation from this object is thermal emission from a cooling neutron star. For this black-body temperature we can o

Z. I. Tsvetanov, G. F. Hartig, H. C. Ford, G. A. Kriss

The nuclear spectrum of M87 covering the Ly_a-H_a wavelength range was obtained with the HST Faint Object Spectrograph (FOS) trough a 0.21 arcsec aperture. Contrary to some previous claims, a single power law (F(nu)~nu^(-a)) can not reproduce the observed continuum shape and at least a broken power law is require for a good fit (a = 1.75 and 1.41 shortward a

J. A. Stepanian, V. A. Lipovetsky, V. H. Chavushyan, L. K. Erastova

The data for 100 QSOs from the Second Byurakan Survey (SBS) located on the northern sky 8h < R.A. < 17h and 49deg < Dec. < 61deg are presented. The main parameters of emission lines and the other data for all QSOs as wel as their scans are given. Totally we have found 216 QSOs in SBS.

Janet E. Drew, Daniel Proga, James M. Stone

A radiation-driven disk wind model is proposed that offers great promise of explaining the extreme mass loss signatures of massive young stellar objects (the BN-type objects and more luminous Herbig Be stars). It is argued that the dense low-velocity winds associated with young late-O/early-B stars would be the consequence of continuing optically-thick accre

K. A. Postnov, M. E. Prokhorov

Gravitational wave noise associated with unresolved binary stars in the Galaxy is studied with the special aim of determining the upper frequency at which it stops to contribute at the rms noise level of the proposed space-born interferometer (LISA). The upper limit to this background is derived from the statistics of SN Ia explosions, part of which can be t

Sang-Hyeon Ahn, Hee-Won Lee

Various types of galaxies observed in the cosmological scales show P-Cygni type profiles in the Lyman alpha emission lines. A Monte Carlo code is developed to investigate the Lyman alpha line transfer in an optically thick and moving medium with a careful consideration of the scattering in the damping wing. The main features in emergent line profiles include

Stephane Darbon, Jean-Marie Perrin, Jean-Pierre Sivan

We present low-dispersion visible spectra of two regions of the 30 Doradus nebula. When corrected for atomic continuum emission and divided by the spectrum of the exciting and illuminating stars, one of the two spectra clearly shows Extended Red Emission (ERE) superimposed on the scattering component. This ERE band peaks around 7270 Åand is 1140 Åwidth. HAC

Charles H. Lineweaver

The CMB is already one of the pillars of the Big Bang model. However it may also become our most powerful tool to distinguish contending models and to determine their cosmological parameters. To realize this goal, more than 20 observational groups and two new satellites are gearing up to make precise measurements of the CMB at small angular scales. In such a

I. M. Hook, R. G. McMahon

We report the discovery of two radio-loud quasars with redshifts greater than four; GB1428+4217 with z=4.72 and GB1713+2148 with z=4.01. This doubles the number of published radio-selected quasars with z > 4, bringing the total to 4. GB1428+4217 is the third most distant quasar known and the highest redshift radio and X-ray source currently known. It has a r

Lee Smolin

Three observational tests of cosmological natural selection, a theory that follows from some hypotheses about quantum gravity, are described. If true, this theory explains the choices of the parameters of the standard model of particle physics. The first, the observation of a pulsar with mass greater than $2.5 M_\circ$, would cleanly refute the theory. The s

Carlos Simpson

If $X$ is a smooth projective variety moving in a family, we define a secondary Kodaira-Spencer class for nonabelian Dolbeault cohomology $Hom(X_{Dol}, T)$ of $X$ with coefficients in the complexified 2-sphere $T=S^2\otimes \cc$ (which is a 3-stack on $Sch /\cc$). Let $Z$ be a simply connected projective surface with $h^{2,0}\neq 0$, and let $X$ be the blow-

Shmuel Elitzur, Amit Giveon, David Kutasov, David Tsabar

We discuss some aspects of the physics of branes in the presence of orientifolds and the corresponding worldvolume gauge dynamics. We show that at strong coupling orientifolds sometimes turn into bound states of orientifolds and branes, and give a worldsheet argument for the flip of the sign of an orientifold plane split into two disconnected parts by an NS

Sudip Chakravarty

The interlayer tunneling mechanism of the cuprate high temperature superconductors involves a conversion of the confinement kinetic energy of the electrons perpendicular to the CuO-planes ($c$-axis) in the normal state to the pair binding energy in the superconducting state. This mechanism is discussed and the arguments are presented from the point of view o

Danny Birmingham, Ivo Sachs, Siddhartha Sen

It is observed that the three-dimensional BTZ black hole is a supersymmetric solution of the low-energy field equations of heterotic string theory compactified on an Einstein space. The solution involves a non-zero dilaton and NS-NS H-field. The entropy of the extreme black hole can then be computed using string theory and the asymptotic properties of anti-d

R. Jedicke, T. S. Metcalfe

We have developed a model-independent analytical method for debiasing the four-dimensional (a,e,i,H) distribution obtained in any asteroid observation program and have applied the technique to results obtained with the 0.9m Spacewatch Telescope. From 1992 to 1995 Spacewatch observed ~3740 deg^2 near the ecliptic and made observations of more than 60,000 aste

Alexander Kusenko, Mikhail Shaposhnikov, P. G. Tinyakov, Igor I. Tkachev

Electroweak models with low-energy supersymmetry breaking predict the existence of stable non-topological solitons, Q-balls, that can be produced in the early universe. The relic Q-balls can accumulate inside a neutron star and gradually absorb the baryons into the scalar condensate. This causes a slow reduction in the mass of the star. When the mass reaches

A. H. Jaffe, M. Kamionkowski

We present a new derivation of the cosmic microwave background anisotropy spectrum from the Ostriker-Vishniac effect for an open, flat, or closed Universe, and calculate the anisotropy expected in cold dark-matter (CDM) models. We provide simple semi-analytic fitting formulas for the Vishniac power spectrum that can be used to evaluate the expected anisotrop

B. M. Brown, M. S. P. Eastham, D. K. R. McCormack, M. Plum

The paper reports on computation of verified enclosures for the Titchmarsh-Weyl m-function. It examines some cases in which Lohner&#39;s AWA algorithm must be suplimented by mathematical analysis.

B. Alles, A. Feo, H. Panagopoulos

We calculate the 3-loop perturbative expansion of the average plaquette in lattice QCD with N_f massive Wilson fermions and gauge group SU(N). The corrections to asymptotic scaling in the corresponding energy scheme are also evaluated. We have also improved the accuracy of the already known pure gluonic results at 2 and 3 loops.

V. E. Lyubovitskij, E. Z. Lipartia, A. G. Rusetsky

The perturbative framework is developed for the calculation of the pi(+)pi(-) atom characteristics on the basis of the field-theoretical Bethe-Salpeter approach. A closed expression for the first-order correction to the pi(+)pi(-) atom lifetime has been obtained.

Tohru Eguchi, Chuan-Sheng Xiong

We construct topological recursion relations (TRR&#39;s) at higher genera $g\ge2$ for general 2-dimensional topological field theories coupled to gravity. These TRR&#39;s when combined with Virasoro conditions enable one to determine the number of higher genus holomorphic curves in any Fano varieties. In the case of $CP^2$ we reproduce the known results at g

Deepto Chakrabarty, Victoria M. Kaspi

We report on high-speed optical photometry of the radio positions of two young rotation-powered pulsars. No pulsations were detected from the optical counterpart proposed by Caraveo et al. (1994) for PSR B1509-58, with a 2 sigma upper limit on the pulsed fraction of 12 percent, significantly lower than that measured in the five known optical pulsars. Given i

Craig A. Tracy, Harold Widom

In this expository article we describe the asymptotics of certain Fredholm determinants which provide solutions to the cylindrical Toda equations, and we explain how these asymptotics are derived. The connection with Fredholm determinants arising in the theory of random matrices, and their asymptotics, are also discussed.

Hasan Gumral

The motion of an incompressible fluid in Lagrangian coordinates involves infinitely many symmetries generated by the left Lie algebra of group of volume preserving diffeomorphisms of the three dimensional domain occupied by the fluid. Utilizing a 1+3-dimensional Hamiltonian setting an explicit realization of this symmetry algebra and the related Lagrangian a

S. Hirenzaki, H. Toki

We study $(n,d)$ and (d,$^3$He) reactions on $^{208}Pb$ leading to deeply bound pionic atoms with one neutron hole being left. We develop a theoretical model to calculate cross sections of deeply bound pionic atoms and quasi-elastic pion production. The results are compared with data which have been obtained so far. We show that the theoretical model describ

Nik Weaver

Every Heisenberg manifold has a natural &#34;sub-Riemannian&#34; metric with interesting properties. We describe the corresponding noncommutative metric structure for Rieffel&#39;s quantum Heisenberg manifolds.

Steven G. Krantz

Many important journal functions would be lost if the mathematical community replaced all paper journals with electronic media. Electronic media are useful for some purposes, but they will not be the basis for a publishing revolution in the near future.

Ilka Brunner, Amihay Hanany, Andreas Karch, Dieter Lust

We study brane realizations of chiral matter in N=1 supersymmetric gauge theories in four dimensions. A &#34;cross&#34; configuration which leads to &#34;flavor doubling&#34; is found to have a superpotential. The main example is realized using a special &#34;fork&#34; configuration. Many of the results are found by studying a SU times SU product gauge group

Evgeny Ivanov, Boris Zupnik

We study realization of N=2 SUSY in N=2 abelian gauge theory with electric and magnetic $FI$ terms within a manifestly supersymmetric formulation. We find that after dualization of even one $FI$ term N=2 SUSY is realized in a partial breaking mode off shell. In the case of two $FI$ terms, this regime is preserved on shell. The N=2 SUSY algebra is shown to be

T. Padmanabhan

The gap between a microscopic theory for quantum spacetime and the semiclassical physics of blackholes is bridged by treating the blackhole spacetimes as highly excited states of a class of nonlocal field theories. All the blackhole thermodynamics is shown to arise from asymptotic form of the dispersion relation satisfied by the elementary excitations of the

Laurent Baulieu, Celine Laroche

We classify possible `self-duality&#39; equations for p-form gauge fields in space-time dimension up to D=16, generalizing the pioneering work of Corrigan et al. (1982) on Yang-Mills fields (p=1) for D from 5 to 8. We impose two crucial requirements. First, there should exist a 2(p+1)-form T invariant under a sub-group H of SO(D). Second, the representation

G. S. Danilov

Superstring amplitudes of an arbitrary genus are calculated through super-Schottky parameters by a summation over the fermion strings. For a calculation of divergent multi-loop fermion string amplitudes a supermodular invariant regularization procedure is used. A cancellation of divergences in the superstring amplitudes is established. Grassmann variables ar

V. R. Khalilov, Choon-Lin Ho

Exact solutions of Dirac equation in two spatial dimensions in the Coulomb field are obtained. Equation which determines the so-called critical charge of the Coulomb field is derived and solved for a simple model.

Ilka Agricola

We determine all Lie groups compatible with the gauge structure of the Standard Elementary Particle Model (SM) and their representations. The groups are specified by congruence equations of quantum numbers. By comparison with the experimental results, we single out one Lie group and show that this choice implies certain old and new correlations between the q

Gordon Chalmers, Warren Siegel

Manifestly Lorentz covariant Feynman rules are given in terms of a &#34;scalar&#34; field for each helicity, dramatically simplifying the calculation of amplitudes with massless particles. The spinor helicity formalism is properly identified as a null complex spacelike (not lightlike) gauge, where two massless external momenta define the reference frame. Usu

S. G. Matinyan, W. D. Walker

We discuss the multiplicity distribution for highest accessible energies of $pp$- and $\bar pp$- interactions from the point of view of the multiparton collisions. The inelastic cross sections for the single, $σ_1$, and multiple (double and, presumably, triple, $σ_{2+3}$) parton collisions are extracted from the analysis of the experimental data on the multi

Andrzej Czarnecki, William J. Marciano, Kirill Melnikov

Transition rates for coherent muon-electron conversion in muonic atoms, mu+N --> e+N, are computed for various types of muon number violating interactions. Attention is paid to relativistic atomic effects, Coulomb distortion, finite nuclear size, and nucleon distributions. Discrepancies with previously published results are pointed out and explained. Results

Malgorzata Bakalarska, Waclaw Tybor

The interaction of the notivarg with an external Weyl current is discussed. The continuity equation for the Weyl current is obtained. The canonical analysis of the theory of the notivarg interacting with the external Weyl current is performed. The covariant propagator of the notivarg is found.

Tao Huang, Ai-lin Zhang

The mass of the lowest scalar glueball is discussed by using QCD sum rules. We find that the glueball mass is sensitive to the choice of moments and slightly depends on the radiative corrections. With the help of suitable moments and stability criteria, we get the scalar glueball mass: $1710\pm110$ MeV without radiative corrections and $1580\pm150$ MeV with

J. M. Cline

I describe work done in collaboration with M. Joyce and K. Kainulainen on (1) the strength of the electroweak phase transition in the MSSM and (2) the mechanism for producing the baryon asymmetry during the phase transition. In the former we compare the effective potential and dimensional reduction methods for describing the phase transition and search the p

T. Pradhan

It is shown that electrons and photons can be considered as composities of particles representating the fundamental representation of the extended Lorentz group $SU(3)\otimes SU(3)$ in (8+1) dimensional space-time which are held together by force mediated by gauge particles belonging to the regular representation. In this theory, spin states of electron, pos

The WA102 Collaboration, D. Barberis et al

The reaction pp -> pf (pi+pi-pi0) ps has been studied at 450 GeV/c in an experiment designed to search for gluonic states. A spin analysis has been performed and the dPT filter applied. The analysis confirms the previous observation that all undisputed qqbar states are suppressed at small dPT. In addition, a clear difference is observed in the production mec

F. J. Chinea

A new first integral for the equations corresponding to twisting type-N vacuum gravitational fields with two non-commuting Killing vectors is introduced. A new reduction of the problem to a complex second-order ordinary differential equation is given. Alternatively, the mentioned first integral can be used in order to provide a first integral of the second-o

Ph. Droz-Vincent

We consider the Klein-Gordon equation in FRW-like spacetimes, with compact space sections (not necessarily isotropic neither homogeneous). The bi-scalar kernel allowing to select the positive-frequency part of any solution is developed on mode solutions, using the eigenfunctions of the three-dimensional Laplacian. Of course this kernel is not unique but, exc

Enrico Montanari

The equations of a resonant sphere in interaction with $N$ secondary radial oscillators (transducers) on its surface have been found in the context of Lagrangian formalism. It has been shown the possibility to exert a veto against spurious events measuring the longitudinal component of a signal. Numerical simulations has been performed, which take into accou

I-Ching Yang

Using Einstein&#39;s and Weinberg&#39;s energy complex, we evaluate the energy distribution of the vaccum nonsingularity black hole solution. The energy distribution is positive everywhere and be equal to zero at origin.

Masaru Shibata, Keisuke Taniguchi, Takashi Nakamura

In this paper, we present results obtained from our recent studies on the location of the innermost stable circular orbit (ISCO) for binary neutron stars (BNSs) in several levels of post Newtonian (PN) approximations. We reach the following conclusion at present: (1) even in the Newtonian case, there exists the ISCO for binary of sufficiently stiff equation

C. W. Gardiner, M. D. Lee, R. J. Ballagh, M. J. Davis

A major extension of the model of condensate growth introduced by us is made to take account of the evolution of the occupations of lower trap levels (quasiparticles) by scattering processes, and of the full Bose-Einstein formula for the occupations of higher trap levels, which are assumed to have a time independent occupation. The principal effect is a spee

L. Frachebourg, P. L. Krapivsky

We study a cyclic Lotka-Volterra model of N interacting species populating a d-dimensional lattice. In the realm of a Kirkwood approximation, a critical number of species N_c(d) above which the system fixates is determined analytically. We find N_c=5,14,23 in dimensions d=1,2,3, in remarkably good agreement with simulation results in two dimensions.

Patrice Simon, Howard A Gutowitz

We investigate a cellular automaton (CA) model of traffic on a bi-directional two-lane road. Our model is an extension of the one-lane CA model of {Nagel and Schreckenberg 1992}, modified to account for interactions mediated by passing, and for a distribution of vehicle speeds. We chose values for the various parameters to approximate the behavior of real tr

A. H. MacDonald, T. Jungwirth, M. Kasner

In itinerant electron ferromagnets spectral weight is transferred at finite temperatures from quasiparticle peaks located at majority and minority-spin band energies to shadow-band peaks. For a given Bloch wavevector and band index, the majority-spin shadow-band peak is located near the minority-spin quasiparticle energy and the minority-spin shadow-band pea

Patrice Simon, Kai Nagel

We systematically investigate the effect of blockage sites in a cellular automaton model for traffic flow. Different scheduling schemes for the blockage sites are considered. None of them returns a linear relationship between the fraction of ``green&#39;&#39; time and the throughput. We use this information for a fast implementation of traffic in Dallas.

Martin M. Rieger, R. W. Godby

We present a method to calculate the electronic charge density of periodic solids in the GW approximation, using the space-time method. We investigate for the examples of silicon and germanium to what extent the GW approximation is charge-conserving and how the charge density compares with experimental values. We find that the GW charge density is close to e

C. Reichhardt, C. J. Olson, Franco Nori

As a function of applied field, we find a rich variety of ordered and partially-ordered vortex lattice configurations in systems with square or triangular arrays of pinning sites. We present formulas that predict the matching fields at which commensurate vortex configurations occur and the vortex lattice orientation with respect to the pinning lattice. Our r

N. I. Lebovka, Y. V. Ivanenko, N. V. Vygornitskii

The results of the computer simulation of the aggregates growth of the similarly charged particles in the framework of deterministic Laplacian growth model on a square lattice are presented. Cluster growth is controlled by three parameters ${p, E,λ}$, where $p$ - Laplacian growth parameter, $E$ - energy of a particle sticking to a cluster, $λ$ - the screenin

Michele Vendruscolo

In suitable environments, proteins, nucleic acids and certain synthetic polymers fold into unique conformations. This work shows that it is possible to construct lattice models of foldable heteropolymers by expressing the energy only in terms of individual properties of monomers, such as the exposure to the solvent and the steric factor.

M. A. Vesaghi, A. Shafiekhani

Liquid gas was used to produce DLC films on Cu, Al and steel substrates by DC plasma technique. The absorption in IR reflectance indicates, grown films are DLC. By deconvolution of room temperature UV-visible spectra of the films grown at 50 mtorr and 200${}^\circ$C, in addition to the spectra lines reported for CL, PL, PLC and ESR, some new spectra lines we

Gregory Johnson, Andrew I. Melcuk, Harvey Gould, W. Klein

We present molecular dynamics results for a two component, two-dimensional Lennard-Jones supercooled liquid near the glass transition. We find that the supercooled liquid is spatially heterogeneous and that there are long-lived clusters whose size distribution satisfies a scaling relation up to a cutoff. The similarity of several properties of the supercoole

A. Rosch, T. Kopp

We calculate the mobility of a heavy particle coupled to a Fermi sea within a non-perturbative approach valid at all temperatures. The interplay of particle recoil and of strong coupling effects, leading to the orthogonality catastrophe for an infinitely heavy particle, is carefully taken into account. We find two novel types of strong coupling effects: a ne