January 1999 arXiv papers

J. M. Evans, M. Hassan, N. J. MacKay, A. J. Mountain

Local conserved charges in principal chiral models in 1+1 dimensions are investigated. There is a classically conserved local charge for each totally symmetric invariant tensor of the underlying group. These local charges are shown to be in involution with the non-local Yangian charges. The Poisson bracket algebra of the local charges is then studied. For ea

T. M. Aliev, M. Savci

The branching ratio, forward-backward asymmetry and CP violating asymmetry for (B -> X_d l^+ l^-) decay, in framework of the general two Higgs doublet model, with extra phase angle in the charged-Higgs-fermion coupling, are calculated. It is shown that studying the CP violating asymmetry is an efficient tool for establishing new physics.

Abhishek Dhar, Satya N. Majumdar

We study the distribution of residence time or equivalently that of ``mean magnetization" for a family of Gaussian Markov processes indexed by a positive parameter $α$. The persistence exponent for these processes is simply given by $θ=α$ but the residence time distribution is nontrivial. The shape of this distribution undergoes a qualitative change as $

A. Gashi, E. Matsinos, G. C. Oades, G. Rasche

This work presents the results of a revised analysis of the low-energy (pion laboratory kinetic energy T(sub pi) < 100 MeV) pi+ p data using recently obtained electromagnetic corrections. The measurements are analyzed assuming extended threshold expansions for the hadronic K-matrix elements. With a few exceptions, the description of the experimental data is

G. V. Gadiyak, E. A. Cheblakova

The two-dimensional flow of viscous incompressible liquid in a square cavity with a free boundary and differentially heated vertical sides is considered in the present work. The influence of gravitational and thermocapillary convection on temperature and velocity fields is studied in large range of dimensionless parameters and similarity criteria using equat

Roger. D. Blandford, David J. Helfand

The recent gamma ray burst, GRB 990123, has an absorption redshift z_s=1.60, implying an apparent energy $E \ge 3 \times 10^{54} erg$, and a peak luminosity $L_{max} \ge 6 \times10^{53}erg/s$, assuming isotropic emission. This energy is ten times larger than hitherto measured and in excess of the rest mass of the sun. Optical observations have revealed an as

Artur G. Sergyeyev

We present the explicit formulae, describing the structure of symmetries and formal symmetries of any scalar (1+1)-dimensional evolution equation. Using these results, the formulae for the leading terms of commutators of two symmetries and two formal symmetries are found. The generalization of these results to the case of system of evolution equations is als

Lin Tang

The effect of histamine (HA) on the electric activities of Purkinje cell (PC) is studied on the cerebellum slice. We find that: (1) HA&#39;s main effect on PC is excitative (72.9%); there are also a small amount of PC showing inhibitive (10.2%) or no (16.9%) response to HA. (2) Different from the conventional opinion, HA&#39;s excitative effect on PC is mutu

Shahar Gov, Shmuel Shtrikman

The U-CAS is a spinning magnetized top that is levitated in a static magnetic field. The field is produced by a permanent magnet base, positioned below the hovering top. In this paper we derive upper and lower bounds for h - the maximum hovering height of this top. We show that the bounds are of the form a*L where a is a dimensionless number ranging from abo

Zhiqin Lu

In this paper, we computed the first three coefficients of the asymptotic expansion of Zelditch. We also proved that in general, the $k$-th coefficient is a polynomial of the curvature and its derivative of weight $k$.

G. A. Vilkovisky

The master equation is quantized. This is an example of quantization of a gauge theory with nilpotent generators. No ghosts are needed for a generation of the gauge algebra. The point about the nilpotent generators is that one can&#39;t write down a single functional integral for this theory. One has to write down a product of two coupled functional integral

Renata Kallosh

The motion of a particle near the RN black hole horizon is described by conformal mechanics. Models of this type have no ground state with vanishing energy. This problem was resolved in past by a redefinition of the Hamiltonian which breaks translational time invariance but gives a normalizable ground state. We show that this change of the Hamiltonian is a q

Remo Garattini

Following the subtraction procedure for manifolds with boundaries, we calculate by variational methods, the Schwarzschild and Flat space energy difference. The one loop approximation for TT tensors is considered here. An analogy between the computed energy difference in momentum space and the Casimir effect is illustrated. We find a singular behaviour in the

David Tong

We study classical solutions of N=4 super Yang-Mills theories that are invariant under 1/4 of the supersymmetry generators. Expressions for the mass and electric charge of the configurations are derived as functions on the monopole moduli space. These functions also provide a method of determining the number of normalisable bosonic zero modes.

Mitsuhiro Kato, Tsunehide Kuroki

It is known that the noncommutativity of D-brane coordinate is responsible for describing the higher-dimensional D-branes in terms of more fundamental ones such as D-particles or D-instantons, while considering a noncommutative torus as a target space is conjectured to be equivalent to introducing the background antisymmetric tensor field in matrix models. I

Pankaj Jain, John P. Ralston, George M. Frichter

We study the feasibility of using an isotropic flux of cosmic neutrinos in the energy range of 10 to 10000 TeV to study the interior structure of Earth. The angular distribution of events in a $\sim {\rm km}^3$-scale neutrino telescope can be inverted to yield information on the Earth&#39;s mass distribution that is independent of other methods. The energy s

Alexander Krotov, Mark Hepple, Robert Gaizauskas, Yorick Wilks

Treebanks, such as the Penn Treebank (PTB), offer a simple approach to obtaining a broad coverage grammar: one can simply read the grammar off the parse trees in the treebank. While such a grammar is easy to obtain, a square-root rate of growth of the rule set with corpus size suggests that the derived grammar is far from complete and that much more treebank

K. Sakamoto, S. K. Okumura, S. Ishizuki, N. Z. Scoville

The NRO/OVRO imaging survey of molecular gas in 20 spiral galaxies is used to test the theoretical predictions on bar-driven gas transport, bar dissolution, and bulge evolution. In most galaxies in the survey we find gas condensations of 10^8-10^9 M_sun within the central kiloparsec, the gas masses being comparable to those needed to destroy bars in numerica

Hsiang-nan Li, Blazenka Melic

We extract the B, D, and D* meson wave functions from the CLEO data of the decays B -> K*γand B -> D^(*)πin the perturbative QCD framework. In this formalism, various logarithmic corrections are organized to give the Wilson evolution from the W boson mass down to the characteristic scale of a decay process, which is of order of the b quark mass, and the Suda

The CDF Collaboration

We present the first measurement of associated direct photon + muon production in hadronic collisions, from a sample of 1.8 TeV $p \bar p$ collisions recorded with the Collider Detector at Fermilab. Quantum chromodynamics (QCD) predicts that these events are primarily from the Compton scattering process $cg \to cγ$, with the final state charm quark producing

Masako Bando, Taichiro Kugo

We show that the neutrino masses with large mixing between ν_μand ν_τare naturally reproduced in a supersymmetric E_6 grand unification model with an anomalous U(1)_X symmetry. We propose a simple scenario which incorporates a novel mechanism called `E-twisting&#39; by which all the characteristic features of the fermion mass matrices, not only the quark/lep

Deok-Sun Lee, Doochul Kim

The large deviation function obtained recently by Derrida and Lebowitz for the totally asymmetric exclusion process is generalized to the partially asymmetric case in the scaling limit. The asymmetry parameter rescales the scaling variable in a simple way. The finite-size corrections to the universal scaling function and the universal cumulant ratio are also

M. Kaburagi, H. Kawamura, T. Hikihara

Ordering of frustrated S=1/2 and 1 XY and Heisenberg spin chains with the competing nearest- and next-nearest-neighbor antiferromagnetic couplings is studied by exact diagonalization and density-matrix renormalization-group methods. It is found that the S=1 XY chain exhibits both gapless and gapped `chiral&#39; phases characterized by the spontaneous breakin

Chung Kao, Doreen Wackeroth

We study loop-induced parity violating asymmetries in the strong production of polarized top quark pairs at $pp$ and $p \bar p$ colliders. The electroweak ${\cal O}(α)$ corrections to the helicity amplitudes of $q \bar q \to t \bar t$ and $gg \to t \bar t$ are evaluated in a two Higgs doublet model (2HDM) and the minimal supersymmetric standard model (MSSM).

Mihoko M. Nojiri, Youichi Yamada

We study the distribution of lepton pairs from the second lightest neutralino decay \tchi^0_2\to\tchi^0_1 l^+l^-. This decay mode is important to measure the mass difference between \tchi^0_2 and the lightest neutralino \tchi^0_1, which helps to determine the parameters of the minimal supersymmetric standard model at the CERN LHC. We found that the decay dis

N. Fukushima, T. Kojima

We study the multi-channel Kondo model associated with an integrable higher-spin analogue of the anti-ferroelectric six-vertex model, which is constructed by inserting spin 1/2 to spin 1 lines: $... C^3 \otimes C^3 \otimes C^2 \otimes C^3 \otimes C^3 ... $. We formulate the problem in terms of representation theory of quantum affine algebra $U_q(hat{sl}_2)$.

Charis Anastopoulos, B. L. Hu

We perform a first- principles derivation of the general master equation to study the non-Markovian dynamics of a two-level atom (2LA) interacting with an electromagnetic field (EMF). We use the influence functional method which can incorporate the full backreaction of the field on the atom, while adopting Grassmannian variables for the 2LA and the coherent

Aurel Bulgac, Vasily R. Shaginyan

A theoretically consistent approach to the calculation of the Coulomb correlation corrections to the single--particle energies is presented. New contributions to the single--particle energies previously overlooked in the literature are now identified and taken into account. We show that the interplay between the Coulomb interaction and the strong interaction

Helmuth Huffel, Gerald Kelnhofer

Based on a generalization of the stochastic quantization scheme recently a modified Faddeev-Popov path integral density for the quantization of Yang-Mills theory was derived, the modification consisting in the presence of specific finite contributions of the pure gauge degrees of freedom. Due to the Gribov problem the gauge fixing can be defined only locally

D. A. Demir

Starting with the equivalence of the rest energy of a particle to an amount of the radiant energy characterized by a frequency, in addition to the usual relativistic transformation rules leading to the wave-particle duality, we investigate the case in which this frequency is an internal propery of the particle. This kind of interpretation of the frequency is

Ricardo Troncoso, Jorge Zanelli

A new family of supergravity theories in odd dimensions is presented. The Lagrangian densities are Chern-Simons forms for the connection of a supersymmetric extension of the anti-de Sitter algebra. The superalgebras are the supersymmetric extensions of the AdS algebra for each dimension, thus completing the analysis of van Holten and Van Proeyen, which was v

C. D. Fosco, R. E. Gamboa Saravi, F. A. Schaposnik

We evaluate the fermionic determinant for massless QED_2 at finite temperature, in the imaginary time formalism. By using a decoupling transformation of the fermionic fields, we show that the determinant factorizes into the usual, temperature independent expression, times an extra factor which depends on the temperature and on the constant component of the g

Daiji Ennyu, Hiroshi Kawabe, Naohito Nakazawa

We apply stochastic quantization method to Kostov&#39;s matrix-vector models for the second quantization of orientable strings with Chan-Paton like factors, including both open and closed strings. The Fokker-Planck hamiltonian deduces an orientable open-closed string field theory at the double scaling limit. There appears an algebraic structure in the contin

G. V. Basalyga, A. K. Gorbatsievich

It is shown that the motion of a multielectron atom in an external gravitational field in a good approximation is described by system of the Mathisson-Papapetrou equations, if we put as a classical angular momentum of the atom the expectation value of the operator of the full angular momentum of the system, which includes spins of the nucleus and electrons,

Tobias Gleim, Walter Kob

We present a detailed analysis of the beta-relaxation dynamics of a simple glass former, a Lennard-Jones system with a stochastic dynamics. By testing the various predictions of mode-coupling theory, including the recently proposed corrections to the asymptotic scaling laws, we come to the conclusion that in this time regime the dynamics is described very we

P. Hasenfratz

Experiments and numerical data on the correlation length for large S disagree strongly with the theoretical prediction based on the effective field theory prescription of the magnon physics. The reason is that for large S, at any accessible correlation lengths, the cut-off effects from the non-magnon scales become large and can not be treated by an effective

R. Mukherjee, J. Chiang

We describe the properties of the blazars detected by EGRET and summarize the results on the calculations of the evolution and luminosity function of these sources. Of the large number of possible origins of extragalactic diffuse gamma-ray emission, it has been postulated that active galaxies might be one of the most likely candidates. However, some of our r

Roger. D. Blandford

A brief summary of the properties of astrophysical black holes is presented. Various modes of accretion are distinguished, corresponding to accretion at rates from well below to well above the Eddington rate. The importance of mass loss is emphasized when the accreting gas cannot radiate and it is asserted that a strong wind is likely to be necessary to carr

S. Boettcher

The benefits of a recently proposed method to approximate hard optimization problems are demonstrated on the graph partitioning problem. The performance of this new method, called Extremal Optimization, is compared to Simulated Annealing in extensive numerical simulations. While generally a complex (NP-hard) problem, the optimization of the graph partitions

Gavin E. Crooks

There are only a very few known relations in statistical dynamics that are valid for systems driven arbitrarily far-from-equilibrium. One of these is the fluctuation theorem, which places conditions on the entropy production probability distribution of nonequilibrium systems. Another recently discovered far-from-equilibrium expression relates nonequilibrium

S. Boettcher, A. Percus

We propose a general-purpose method for finding high-quality solutions to hard optimization problems, inspired by self-organizing processes often found in nature. The method, called Extremal Optimization, successively eliminates extremely undesirable components of sub-optimal solutions. Drawing upon models used to simulate far-from-equilibrium dynamics, it c

Anders Johansen, Didier Sornette

Brittle failures of materials and earthquakes generate acoustic/seismic waves which lead to radiation damping feedbacks that should be introduced in the dynamical equations of crack motion. We present direct experimental evidence of the importance of this feedback on the acoustic noise spectrum of well-controlled spring-block sliding experiments performed on

E. J. Ferrer, V. P. Gusynin, V. de la Incera

The catalysis of chiral symmetry breaking by an applied constant magnetic field and in the presence of boundaries along third axis is investigated in the four-dimensional Nambu-Jona-Lasinio model. It is shown that in case of periodic boundary conditions for fermions the magnetic field breaks the chiral symmetry, generating a dynamical mass even at the weakes

Patricia Purdue

When a self-gravitating body (e.g., a neutron star or black hole) interacts with an external tidal field (e.g., that of a binary companion), the interaction can do work on the body, changing its mass-energy. The details of this &#34;tidal heating&#34; are analyzed using the Landau-Lifshitz pseudotensor and the local asymptotic rest frame of the body. It is s

A. Le Fevre, M. Ploszajczak, V. D. Toneev

The shape influence of decaying thermalized source on various characteristics of multifragmentation as well as its interplay with effects of angular momentum and collective expansion are first studied and the most pertinent variables are proposed. The analysis is based on the extension of the statistical microcanonical multifragmentation model.

W. Lerche, S. Stieberger, N. P. Warner

We investigate the prepotential that describes certain F^4 couplings in eight dimensional string compactifications, and show how they can be computed from the solutions of inhomogenous differential equations. These appear to have the form of the Picard-Fuchs equations of a fibration of Sym^2(K3) over P^1. Our findings give support to the conjecture that the

Stephen L. Adler

We reanalyze our recently proposed mass matrix model based on spontaneously broken discrete chiral family symmetry, taking into account the additional flavor changing neutral current constraint implied by the bound on the $D_1-D_2$ mass difference, and including several corrections to our earlier analysis. When combined, the $K_1-K_2$ and $D_1-D_2$ constrain

Piljin Yi

We argue that M2 brane is realized as a topological soliton on a coincident pair of M5 and anti-M5 branes, as the two five-branes annihilate each other. Topology and quantum numbers of this world-volume soliton are discussed in some detail, and its formation is explained qualitatively. It follows from a compactification that a D4-anti-D4 pair annihilate and

WA98 Collaboration, M. M. Aggarwal et al

Neutral pion production in central 158AGeV Pb+Pb collisions has been studied in the WA98 experiment at the CERN SPS. The pi0 transverse mass spectrum has been analyzed in terms of a thermal model with hydrodynamic expansion. The high accuracy and large kinematic coverage of the measurement allow to limit previously noted ambiguities in the extracted freeze-o

R. Prozorov, D. Giller

We revise the applicability of the theory of self-organized criticality (SOC) to the process of magnetic relaxation in type-II superconductors. The driving parameter of self-organization of vortices is the energy barrier for flux creep and not the current density. The power spectrum of the magnetic noise due to vortex avalanches is calculated and is predicte

Gunnar S. Bali

I review recent Lattice results. In particular, the confinement mechanism and string breaking, glueballs and hybrid mesons as well as light hadron spectroscopy are discussed.

T. Suzuki, H. Sakai, T. Tatsumi

The Landau-Migdal parameters for nucleon-nucleon (g&#39;_NN) and nucleon-Δ(g&#39;_NΔ) couplings are estimated from recent experimental data on the giant Gamow-Teller state of 90Nb. The observed quenching of the GT strength by 10% provides 0.16<g&#39;_NΔ<0.23 for g&#39;_ΔΔ<1.0, while the excitation energy g&#39;_NN\sim 0.59. The critical density of pion conde

Glenn Starkman, Mark Trodden, Tanmay Vachaspati

Current observations of Type Ia supernovae provide evidence for cosmic acceleration out to a redshift of $z \lsim 1$, leading to the possibility that the universe is entering an inflationary epoch. However, inflation can take place only if vacuum-energy (or other sufficiently slowly redshifting source of energy density) dominates the energy density of a regi

Philip Pearle

This is a review of formalisms and models (nonrelativistic and relativistic) which modify Schrodinger&#39;s equation so that it describes wavefunction collapse as a dynamical physical process.

M. Ardehali, H. F. Chau, Hoi-Kwong Lo

We devise a simple modification that essentially doubles the efficiency of a well-known quantum key distribution scheme proposed by Bennett and Brassard (BB84). Our scheme assigns significantly different probabilities for the different polarization bases during both transmission and reception to reduce the fraction of discarded data. The actual probabilities

S. S. Elbakian, H. B. Nersisyan

The excitation of electromagnetic (EM) wake waves in electron plasma by an one-dimensional bunch of charged particles has been considered in the presence of intense monochromatic circularly polarized electromagnetic (CPEM) pump wave. In the zero state (in the absence of bunch) the interaction of the pump wave with plasma is described by means of Maxwell equa

S. G. Arutunian, N. M. Dobrovolski, S. L. Egiazarian, M. R. Mailian

Magnetic interaction between a weighing sample and an external magnetic field allows to measure characteristics of magnetic field (a sample with known magnetic characteristics), as well as the magnetic properties of a sample (a known magnetic field). Measurement of materials magnetic permeability is a well known application of this method. In this paper we r

Yuji Igarashi, Katsmi Itoh, Ken Nakanishi, Kazuhiro Ogura

A system of first-order differential-difference equations with time lag describes the formation of density waves, called as quasi-solitons for dissipative systems in this paper. For co-moving density waves, the system reduces to some exactly solvable lattice models. We construct a shock-wave solution as well as one-quasi-soliton solution, and argue that ther

Jules Deutsch

The interest, the status and the perspectives of various experiments in neutron and nuclear beta-decay, muon-decay and pion-decays are discussed. The talk is segmented into a discussion of the decay-rates and of the energy-spectra and correlations. The impact on various scenarios of &#34;new physics&#34; is briefly mentioned; left-right symmetric models are

Serdar Kuyucak, Michiaki Sugita

The self-consistent cranking method is tested by comparing the cranking calculations in the interacting boson model with the exact results obtained from the SU(3) and O(6) dynamical symmetries and from numerical diagonalization. The method is used to study the spin dependence of shape variables in the $sd$ and $sdg$ boson models. When realistic sets of param

Dave Auckly, Lev Kapitanski, Warren White

In this paper we introduce a new method to design control laws for non-linear underactuated systems. Our method produces an infinite dimensional family of control laws, whereas most control techniques only produce a finite dimensional family. These control laws each come with a natural Lyapunov function. The inverted pendulum cart is used as an example. In a

Tom Leinster

In this paper we answer the question: `what kind of a structure can a general multicategory be enriched in?&#39; The answer is, in a sense to be made precise, that a multicategory of one type can be enriched in a multicategory of the type one level up. In the case of ordinary categories this reduces to something surprising: a category may be enriched in an `

Thomas Friedrich, Andrzej Trautman

It is shown that every bundle $\varSigma\to M$ of complex spinor modules over the Clifford bundle $\Cl(g)$ of a Riemannian space $(M,g)$ with local model $(V,h)$ is associated with an lpin (&#34;Lipschitz&#34;) structure on $M$, this being a reduction of the ${\Ort}(h)$-bundle of all orthonormal frames on M to the Lipschitz group $\Lpin(h)$ of all automorphi

Jürgen Eichhorn, Rudolf Schmid

We endow the group of invertible Fourier integral operators on an open}manifold with the structure of an ILH Lie group. This is done by establishing such structures for the groups of invertible pseudodifferential operators and contact transformations on an open manifold of bounded geometry, and gluing those together via a local section.

Teodor Banica

If B is C*-algebra of finite dimension n>3 then the finite dimensional irreducible representations of the compact quantum automorphism group of B, say G, have the same fusion rules as the ones of SO(3). As consequences, we get (1) a structure result for G in the case where B is a matrix algebra (2) if n>4 then the dual of G is not amenable (3) the fixed poin

Klaus Junemann, Olaf Lechtenfeld, Alexander D. Popov

By carefully analysing the picture-dependence of the BRST cohomology an infinite set of symmetry charges of the closed N=2 string is identified. The transformation laws of the physical vertex operators are shown to coincide with the linearised non-local symmetries of the Plebanski equation (which is the effective field theory of the closed N=2 string). Moreo

Jan-Willem van Holten, Andrew Waldron, Kasper Peeters

On manifolds with non-trivial Killing tensors admitting a square root of the Killing-Yano type one can construct non-standard Dirac operators which differ from, but commute with, the standard Dirac operator. We relate the index problem for the non-standard Dirac operator to that of the standard Dirac operator. This necessitates a study of manifolds with tors

J. M. F. Labastida, Carlos Lozano

We present a summary of the progress made in the last few years on topological quantum field theory in four dimensions. In particular, we describe the role played by duality in the developments which led to the Seiberg-Witten invariants and their relation to the Donaldson invariants. In addition, we analyze the fruitful framework that this connection has ori

P. Bozhilov

We consider a model for tensionless (null) super p-branes with N chiral supersymmetries in ten dimensional flat space-time. After establishing the symmetries of the action, we give the general solution of the classical equations of motion in a particular gauge. In the case of a null superstring (p=1) we find the general solution in an arbitrary gauge. Then,

Elena L. Gubankova, Hans-Christian Pauli, Franz J. Wegner, Gabor Papp

The technique of Hamiltonian flow equations is applied to the canonical Hamiltonian of quantum electrodynamics in the front form and 3+1 dimensions. The aim is to generate a bound state equation in a quantum field theory, particularly to derive an effective Hamiltonian which is practically solvable in Fock-spaces with reduced particle number. The effective H

Andre L. Mota, M. Carolina Nemes, Brigitte Hiller, Hans Walliser

In the present paper we implement a non-trivial and renormalizable extension of the NJL model. We discuss the advantages and shortcomings of this extended model compared to a usual effective Pauli-Villars regularized version. We show that both versions become equivalent in the case of a large cutoff. Various relevant mesonic observables are calculated and co

Peter Watson

A recent form of the Slavnov-Taylor identity for the ghost-gluon vertex of QCD is compared with perturbative results. It is found that this identity, derived assuming ghost-ghost scattering can be neglected, is not consistent with perturbation theory. A new identity is derived at the one-loop perturbative level.

Xin He Meng, Bin Wang, S. Feng

Measurements of the distances to SNe Ia have produced strong evidence that the Universe is really accelarating, implying the existence of a nearly uniform component of dark energy with the simplest explanation as a cosmological constant. In this paper a small changing cosmological term is proposed, which is a function of a slow-rolling scalar field, by which

K. Philippides, W. J. Stirling

The W-fusion scattering process W+W- --> ZZ for off-shell W bosons is studied, focusing on the issue of its high-energy behaviour which is known to be anomalous. It is shown that the unitarity violating terms can be isolated and extracted in a well-defined and efficient way using the pinch-technique. This restores the good high energy behaviour of the cross

H. Athar

We study neutrino conversions in the recently envisaged source of high energy ($E \geq 10^{6}$ GeV) neutrinos, that is, in the vicinity of cosmological gamma-ray burst fireballs (GRB). We consider mainly the possibility of neutrino conversions due to an interplay of neutrino transition magnetic moment, $μ$, and the violation of equivalence principle (VEP), p

Michael Krämer

Recent advances in the theoretical description of radiative Upsilon decays are reviewed, including the calculation of next-to-leading order QCD corrections to the photon spectrum.

M. A. Braun

The 2nd order bootstrap relation is discussed in view of the recent critics by F.Fadin, R.Fiore y A.Papa. It is shown that the strong bootstrap condition and the anzatz to solve it used in our earlier paper are valid at least for the quark part of the next-to-leading contribution.

Alan Horowitz

Chiral gauge groups acting on a lattice fermion field are constructed such that all fermion modes (doublers) have the same charge. Details are given for an abelian axial gauge group within a perturbative framework. An action based on this group correctly reproduces the continuum gauge-current anomaly, while preserving global chiral symmetry, locality, rotati

M. E. Berbenni-Bitsch, M. Göckeler, H. Hehl, S. Meyer

Recently, the contributions of chiral logarithms predicted by quenched chiral perturbation theory have been extracted from lattice calculations of hadron masses. We argue that a detailed comparison of random matrix theory and lattice calculations allows for a precise determination of such corrections. We estimate the relative size of the m*log(m), m, and m^2

N. H. Brook

The production of charged particles has been measured in deep inelastic scattering (DIS) with the ZEUS detector. The evolution of the moments of the scaled momenta distributions in $Q^2$ and $x$ has been investigated in the current fragmentation region of the Breit frame. The results in the current region are compared to $e^+e^-$ data and QCD analytical calc

B. Abbott

DO has measured the inclusive production cross section of W and Z bosons in a sample of 13 pb$^{-1}$ of data collected at the Fermilab Tevatron. The cross sections, multiplied by their leptonic branching fractions, for production in pbar-p collisions at sqrt{s}=1.8 TeV are sigma_W*B(W->e nu) = 2.36+-0.02+-0.08+-0.13 nb, sigma_W*B(W->mu nu) = 2.09+-0.06+-0.22

Bin Wang, Ru-Keng Su

Through direct thermodynamic calculations we have shown that different classical entropies of two-dimensional extreme black holes appear due to two different treatments, namely Hawking&#39;s treatment and Zaslavskii&#39;s treatment. Geometrical and topological properties corresponding to these different treatments are investigated. Quantum entropies of the s

Sean A. Hayward

A generally relativistic theory of thermodynamics is developed, based on four main physical principles: heat is a local form of energy, therefore described by a thermal energy tensor; conservation of mass, equivalent to conservation of heat, or the local first law; entropy is a local current; and non-destruction of entropy, or the local second law. A fluid i

E. Kavoussanaki, R. J. Rivers

Zurek has provided a simple picture for the onset of the lamda-transition in He4, not currently supported by vortex density experiments. However, we argue that the seemingly similar argument by Zurek that superflow in an annulus of He4 at the quench will be measurable is still valid.

F. Taddei, S. Sanvito, J. H. Jefferson, C. J. Lambert

We predict that current perpendicular to the plane (CPP) giant magnetoresistance (GMR) in a phase-coherent magnetic multilayer is suppressed when one of the contacts is superconducting. This is a consequence of a superconductivity-induced magneto-resistive (SMR) effect, whereby the conductance of the ferromagnetically aligned state is drastically reduced by

H. Schomerus, E. G. Mishchenko, C. W. J. Beenakker

We investigate current fluctuations in non-degenerate semiconductors, on length scales intermediate between the elastic and inelastic mean free paths. We present an exact solution of the non-linear kinetic equations in the regime of space-charge limited conduction, without resorting to the drift approximation of previous work. By including the effects of a f

John Baker, Giovanni Vignale, A. G. Rojo

In this paper we consider the effect of disorder on the non-dissipative Coulomb drag between two mesoscopic metal rings at zero temperature. Ring 1 has an Aharonov-Bohm flux present which creates a persistent current J_0. Ring 2 interacts with ring 1 via the Coulomb potential and a drag current, J_d is produced. We show that this drag current persists with f

A. Kambili, C. J. Lambert, J. H. Jefferson

For a system of spinless fermions in a disordered mesoscopic ring, interactions can give rise to an enhancement of the persistent current by orders of magnitude. The increase in the current is associated with a charge reorganization of the ground state. The interaction strength for which this reorganization takes place is sample-dependent and the log-average

A. Fabrocini, A. Polls

We study the ground state of a system of Bose hard-spheres trapped in an isotropic harmonic potential to investigate the effect of the interatomic correlations and the accuracy of the Gross-Pitaevskii equation. We compare a local density approximation, based on the energy functional derived from the low density expansion of the energy of the uniform hard sph

J. L. O&#39;Brien, H. Nakagawa, A. S. Dzurak, R. G. Clark

The B-T phase diagram for thin film YBa_2Cu_3O_7-d with B parallel to the superconducting layers has been constructed from GHz transport measurements to 150T. Evidence for a transition from a high T regime dominated by orbital effects, to a low T regime where paramagnetic limiting drives the quenching of superconductivity, is seen. Up to 110T the upper criti

Masanori Ichioka, Akiko Hasegawa, Kazushige Machida

We study the vortex structure and its field dependence within the framework of the quasi-classical Eilenberger theory to find the difference between the d_{x^2-y^2}- and s-wave pairings. We clarify the effect of the d_{x^2-y^2}-wave nature and the vortex lattice effect on the vortex structure of the pair potential, the internal field and the local density of

Philippe Bourges

The spin dynamics of high temperature superconductors measured by inelastic neutron scattering is reviewed. The spin susceptibility evolves a lot with increasing doping from the undoped insulating state to the overdoped metallic state. In the superconducting state, a strong magnetic resonance peak occurs in the spin excitation spectrum whose energy is propor

M. Im, R. E. Griffiths, A. Naim, K. U. Ratnatunga

We have constructed a morphologically divided redshift distribution of faint field galaxies using a statistically unbiased sample of 196 galaxies brighter than I = 21.5 for which detailed morphological information (from the Hubble Space Telescope) as well as ground-based spectroscopic redshifts are available. Galaxies are classified into 3 rough morphologica

Frank C. van den Bosch

A simple, inside-out formation scenario for bulges is presented. Stability arguments are used to suggest that bulges form out of the low-angular momentum baryons that cool inside a virialized dark halo: a self-regulating mechanism transforms part of the baryonic matter into a bulge component, such that the remainder of the baryons can settle in a stable disk

Arpad Szomoru, Puragra Guhathakurta

We present CCD photometry in UBVRI of several thousand Galactic field stars in four large (>1 degree^2) regions centered on diffuse interstellar dust clouds, commonly referred to as ``cirrus&#39;&#39; clouds (with optical depth A_V less than unity). Our goal in studying these stars is to investigate the properties of the cirrus clouds. A comparison of the ob

Magdalen Normandeau

HI spectra towards the W3 HII complex are presented and used to probe the Galactic structure and interstellar medium conditions between us and this region. The overall shape of the spectra is consistent with the predictions of the Two-Arm Spiral Shock model wherein the gas found in the -40 km/s to -50 km/s range has been accelerated by some 20 km/s from its

Luca Amendola, Emilia Palladino

We analyse the Las Campanas Redshift Survey using the integrated conditional density (or density of neighbors) in volume-limited subsamples up to unprecedented scales (200 Mpc/$h$) in order to determine without ambiguity the behavior of the density field. We find that the survey is well described by a fractal up to 20-30 Mpc/$h$, but flattens toward homogene

Renee C. Kraan-Korteweg, Patrick A. Woudt

Various dynamically important extragalactic large-scale structures in the local Universe lie behind the Milky Way. Most of these structures (predicted and unexpected) have only recently been made ``visible&#39;&#39; through dedicated deep surveys at various wavelengths. The wide range of observational searches (optical, near infrared, far infrared, radio and

Todd M. Fuller, Michael J. West, Terry J. Bridges

We have examined the orientations of brightest cluster galaxies (BCGs) in poor MKW and AWM clusters and find that, like their counterparts in richer Abell clusters, poor cluster BCGs exhibit a strong propensity to be aligned with the principal axes of their host clusters as well as the surrounding distribution of nearby (< 20/h Mpc) Abell clusters. The proce

Melvyn Wright, John Dickel, Barron Koralesky, Lawrence Rudnick

We used the BIMA array to map the supernova remnant Cas A from 28 to 87 GHz with 2&#39;&#39; to 7&#39;&#39; angular resolution. Data from 75 to 87 GHz, with 19 pointing centers were combined with single dish data to form a completely sampled image. These new BIMA images were compared with VLA images at 1.5 and 5 GHz to look for spectral index variations acro