March 1996 arXiv papers — page 7

Gail C. McLaughlin, George M. Fuller

We investigate the possibility that neutrino capture on heavy nuclei competes with beta decay in the environment where the $r$-Process elements are synthesized. We find that such neutrino capture is not excluded by existing abundance determinations. We show that inclusion of significant neutrino capture on the (neutron number) N=82 waiting point nuclei can a

Scott Dodelson, Evalyn Gates, Michael S. Turner

Motivated by inflation, the theory of big-bang nucleosynthesis and the quest for a deeper understanding of the fundamental forces and particles, a very successful paradigm for the development of structure in the Universe has evolved. It holds that most of the matter exists in the form of slowly moving elementary particles left over from the earliest moments

Douglas C. Heggie, Piet Hut, Steven L. W. McMillan

We present results on the exchange cross section for the interaction between a hard binary and a field of single stars, for arbitrary masses. The results are based partly on extensive numerical scattering experiments, and partly on analytic estimates of the mass-dependence of the cross section. They can be used to estimate the rate of exchange in an arbitrar

Scott Dodelson, Albert Stebbins

Before decoupling in the early universe, the tightly coupled photon/electron gas underwent acoustic oscillations. These oscillations should be visible today in the spectrum of anisotropies. Recently Fang, Huang, and Wu (1996) claimed that when random processes are accounted for, the phases of these oscillations are no longer coherent. In fact, they claim tha

D. C. Braun, Y. Fan, C. Lindsey, S. M. Jefferies

We measure the mean frequencies of acoustic waves propagating toward and away from a sunspot employing a spot-centered Fourier-Hankel decomposition of p-mode amplitudes as measured from a set of observations made at the South Pole in 1991. We demonstrate that there is a significant frequency shift between the inward and outward traveling waves which is consi

Rafael A. Araya, Alice K. Harding

A recent high resolution measurement of an absorption line at 110 keV in the phase-averaged spectrum of A0535+26 (Grove et al. 1994) and the conspicuous absence of a previously reported harmonic feature at around 50 keV (Kendziorra et al. 1992, 1994) are indicative of cyclotron scattering in a magnetic field of about $10^{13}$G. However, controversy has rise

G. A. Tammann, L. Labhardt, M. Federspiel, A. Sandage

HST has so far provided Cepheid distances to nine galaxies. Although not sufficient yet to determine the distance of the extended Virgo cluster, they are decisive for the distance scale in two ways. (1) Seven of the galaxies contribute to a much improved calibration of the Tully-Fisher relation. Applying this to a complete sample of Virgo spirals one obtains

A. A. Starobinsky

Spectrum of initial scalar and tensor perturbations created during an inflationary stage producing a closed or open FRW universe now is discussed. In the closed case, the CMB temperature anisotropy ${ΔT/T}$ generated by scalar perturbations is enhanced for low multipoles. It is argued that in the open case there is no suppression of low multipoles. A possibi

A. A. Starobinsky

New systematic classification of cosmological models of the present Universe is introduced. After making the comparison of these models with all existing observational data three viable models remain: the cold dark matter model with the cosmological constant (which becomes the most reasonable one if the Hubble constant $H_0>60$ km/s/Mpc); the mixed cold-hot

Vincenzo Carbone, Sandra Savaglio

Ly$α$ forests are usually associated with intergalactic gas clouds intercepting the quasar sight--line. Using as an example the Ly$α$ forest of QSO 0055--26 ($z_{em} = 3.66$), we show that the probability of observing a line at the velocity difference $Δv$ has an intermittent structure in the redshift space. On small scales (70 km~s$^{-1} \leq Δv \leq 1580$

Christian Y. Cardall, George M. Fuller

Two dimensional concordance plots involving the baryon-to-photon ratio, $η$, and an effective number of light neutrinos, $N_ν$, are used to discuss the overall consistency of standard big-bang nucleosynthesis in light of recent determinations of the primordial deuterium ($^2$H) abundance. Observations of high-redshift Ly-$α$ clouds have provided discordant $

David Tytler, Xiao-ming Fan, Scott Burles

We present a measurement of the deuterium to hydrogen ratio in a quasar absorption system at redshift z = 3.57 towards QSO 1937-1009. We use a two component fit, with redshifts determined from unsaturated metal lines, to fit the hydrogen and deuterium features simultaneously. We find a low value of D/H = 2.3 \pm 0.6 \times 10^{-5}, which does not agree with

M. B. Plenio, V. Vedral, P. L. Knight

We present a quantum error correcting code that is invariant under the conditional time evolution between spontaneous emissions and which can correct for one general error. The code presented here generalizes previous error correction codes in that not all errors lead to different error syndromes. This idea may lead to shorter codes than previously expected.

Jonathan W. Keohane, Lawrence Rudnick, Martha C. Anderson

We compare the radio and soft X-ray brightness as a function of position within the young supernova remnant Cassiopeia A. A moderately strong correlation (r = 0.7) was found between the X-ray emission (corrected for interstellar absorption) and radio emission, showing that the thermal and relativistic plasmas occupy the same volumes and are regulated by comm

Martin Gremm, Anton Kapustin, Zoltan Ligeti, Mark B. Wise

The shape of the lepton spectrum in inclusive semileptonic $B\to X\,\ell\,\barν_\ell$ decay is sensitive to matrix elements of the heavy quark effective theory, $\barΛ$ and $λ_1$. From CLEO data we extract $\barΛ=0.39\pm0.11\,$GeV and $λ_1=-0.19\pm0.10\,{\rm GeV}^2$, where the uncertainty is the $1σ$ statistical error only. Systematic uncertainties are discu

Mariana Kirchbach, Andreas Wirzba

The generating functional of heavy baryon chiral perturbation theory at order O(Q^2) in the mean field approximation (with a pseudoscalar source coupling which is consistent with the PCAC-Ward identities on the current quark level) has been exploited to derive Migdal's in--medium pion propagator. It is shown that the prediction for the density dependence

Emilio N. M. Cirillo, E. Olivieri

We study the majority rule transformation applied to the Gibbs measure for the 2--D Ising model at the critical point. The aim is to show that the renormalized hamiltonian is well defined in the sense that the renormalized measure is Gibbsian. We analyze the validity of Dobrushin-Shlosman Uniqueness (DSU) finite-size condition for the "constrained models

R. S. Chivukula, A. G. Cohen, E. H. Simmons

Recent results from CDF indicate that the inclusive cross section for jets with $E_T > 200$ GeV is significantly higher than that predicted by QCD. We describe here a simple flavor-universal variant of the ``coloron" model of Hill and Parke that can accommodate such a jet excess, and which is not in contradiction with other experimental data. As such, th

Stavros Garoufalidis, Jerome Levine

Using the recently developed theory of finite type invariants of integral homology 3-spheres we study the structure of the Torelli group of a closed surface. Explicitly, we construct (a) natural cocycles of the Torelli group (with coefficients in a space of trivalent graphs) and cohomology classes of the abelianized Torelli group; (b) group homomorphisms tha

L. L. Frankfurt, M. M. Sargsian, M. I. Strikman

The cross section of hard semi-exclusive $A(e,e'N)(A-1)$ reactions for fixed missing energy and momentum is calculated within the eikonal approximation. Relativistic dynamics and kinematics of high energy processes are unambiguously accounted for by using the analysis of appropriate Feynman diagrams. A significant dependence of the final state interactio

Karl Jansen, Chuan Liu

We discuss the implementation of a Sheikholeslami-Wohlert term for simulations of lattice QCD with dynamical Wilson fermions as required by Symanzik's improvement program. We show that for the Hybrid Monte Carlo or Kramers equation algorithm standard even-odd preconditioning can be maintained. We design tests of the implementation using analytically and

Josef Dorfmeister, Guido Haak

We start the investigation of immersions $Ψ$ of a simply connected domain $D$ into three dimensional Euclidean space $R^3$, which have constant mean curvature (CMC-immersions), and allow for a group of automorphisms of $D$ which leave the image $Ψ(D)$ invariant. On one hand, this leads to a detailed description of symmetric CMC-surfaces and the associated sy

Sergio Ferrara, Renata Kallosh

The macroscopic entropy-area formula for supersymmetric black holes in N=2,4,8 theories is found to be universal: in d=4 it is always given by the square of the largest of the central charges extremized in the moduli space. The proof of universality is based on the fact that the doubling of unbroken supersymmetry near the black hole horizon requires that all

A. Kricker

Previous work has shown that certain leading orders of arbitrary Vassiliev invariants are generically in the algebra of the coefficients of the Alexander-Conway polynomial \cite{KSA}. Here we illustrate this for a large class of examples, exposing the simple logic behind several existing results in the literature \cite{FKV,BNG}. This approach facilitates an

Y. Ono, T. Ohtsuki, B. Kramer

The scaling property of level statistics in the quantum Hall regime, i.e. 2D disordered electron systems subject to strong magnetic fields, is analyzed numerically in the light of the random matrix theory. The energy dependences of the effective level repulsion parameter, the two level correlation, the GUE-GOE crossover parameter, and the rigidity (or $Δ_3$-

Norbert Grot, Carlo Rovelli, Ranjeet S. Tate

We study the problem of computing the probability for the time-of-arrival of a quantum particle at a given spatial position. We consider a solution to this problem based on the spectral decomposition of the particle's (Heisenberg) state into the eigenstates of a suitable operator, which we denote as the ``time-of-arrival'' operator. We discuss th

Paul Busch, Pekka Lahti

The standard model of the quantum theory of measurement is based on an interaction Hamiltonian in which the observable-to-be-measured is multiplied with some observable of a probe system. This simple Ansatz has proved extremely fruitful in the development of the foundations of quantum mechanics. While the ensuing type of models has often been argued to be ra

S. Sinel'shchikov, L. Vaksman

A standard bicovariant differential calculus on a quantum matrix space ${\tt Mat}(m,n)_q$ is considered. The principal result of this work is in observing that the $U_q\frak{s}(\frak{gl}_m\times \frak{gl}_n))_q$ is in fact a $U_q\frak{sl}(m+n)$-module differential algebra.

Robert Graham

An extension of the Newell-Whitehead-Segel amplitude equation covariant under abritrary rotations is derived systematically by the renormalization group method.

Abhijit Bhattacharyya, Sibaji Raha

An extended version of the Zimanyi-Moskowski (ZM) model has been used to calculate the temperature dependence of the hadronic masses. The calculation of meson masses in the Random Phase Approximation (RPA) gives an increase in the $σ$, $ω$ and $π$ effective masses with temperature.

D. V. Ahluwalia, Mikolaj Sawicki

Using the Weinberg-Soper formalism we construct the front form $(j,0)\oplus(0,j)$ spinors. Explicit expressions for the generalised Melosh transformations up to spin two are obtained. The formalism, without explicitly invoking any wave equations, reproduces spin one half front-form results of Melosh, Lepage and Brodsky, and Dziembowski.

Alberto Garcia, David Vanderbilt

A first-principles study of the vibrational modes of PbTiO_3 in the ferroelectric tetragonal phase has been performed at all the main symmetry points of the Brillouin zone (BZ). The calculations use the local-density approximation and ultrasoft pseudopotentials with a plane-wave basis, and reproduce well the available experimental information on the modes at

Gianfranco Pradisi, Augusto Sagnotti, Yassen S. Stanev

In non-diagonal conformal models, the boundary fields are not directly related to the bulk spectrum. We illustrate some of their features by completing previous work of Lewellen on sewing constraints for conformal theories in the presence of boundaries. As a result, we include additional open sectors in the descendants of $D_{odd}$ $SU(2)$ WZW models. A new

Tamiaki Yoneya

It is generally accepted that the double-scaled 1D matrix model is equivalent to the $c=1$ string theory with tachyon condensation. There remain however puzzles that are to be clarified in order to utilize this connection for our quest towards possible non-perturbative formulation of string theory. We discuss some of the issues that are related to the space-

F. Lizzi, G. Mangano, G. Miele, G. Sparano

The Connes and Lott reformulation of the strong and electroweak model represents a promising application of noncommutative geometry. In this scheme the Higgs field naturally appears in the theory as a particular `gauge boson', connected to the discrete internal space, and its quartic potential, fixed by the model, is not vanishing only when more than one

K. Lechner, M. Tonin

The fields of the conjectured ``heterotic" super--fivebrane sigma--model in ten dimensions are made out of a well known gravitational sector, the $X$ and the $\vartheta$, and of a still unknown heterotic sector which should be coupled to the Yang--Mills fields. We compute the one--loop $d=6$ worldvolume and $D=10$ target space Lorentz--anomalies which ar

K. Lechner, M. Tonin

We determine the two--dimensional Weyl, Lorentz and $κ$--anomalies in the $D=10$ Green--Schwarz heterotic string sigma--model, in an $SO(1,9)$-Lorentz covariant background gauge, and prove their cancellation.

M. Blasone, E. Graziano, O. K. Pashaev, G. Vitiello

In the pseudo-euclidean metrics Chern-Simons gauge theory in the infrared region is found to be associated with dissipative dynamics. In the infrared limit the Lagrangian of 2+1 dimensional pseudo-euclidean topologically massive electrodynamics has indeed the same form of the Lagrangian of the damped harmonic oscillator. On the hyperbolic plane a set of two

Taksu Cheon, T. Shigehara

We examine the quantum motion of two particles interacting through a contact force which are confined in a rectangular domain in two and three dimensions. When there is a difference in the mass scale of two particles, adiabatic separation of the fast and slow variables can be performed. Appearance of the Berry phase and magnetic flux is pointed out. The syst

Geoffrey B. West

This paper is devoted to proving that, in QCD, the lightest glueball state must be the scalar with $J^{PC} = 0^{++}$. The proof relies upon the positivity of the path integral measure in Euclidean space and the fact that interpolating fields for all spins can be bounded by powers of the scalar glueball operator. The problem presented by the presence of vacuu

D. Zeppenfeld

The search for new phenomena at hadron colliders requires a good understanding of QCD processes. The analysis of multi-jet signatures in the top quark search at the Tevatron is one example, forward jet-tagging and rapidity gap techniques in the analysis of weak boson scattering events at the LHC will be another important application. These topics are discuss

K. G. Chetyrkin, A. H. Hoang, J. H. Kuehn, M. Steinhauser

Second order ${\cal O}(\alpha_s^2)$ corrections to the heavy quark production cross-section due to massless quarks and coloured scalars are calculated for all energies above threshold. Based on the method introduced in this letter also the gauge non-invariant second order corrections due to the pure gluonic selfenergy insertion and a certain class of ${\cal{

Y. Kurihara, J. Fujimoto, T. Munehisa, Y. Shimizu

The validity of a photon shower generator QEDPS has been examined in detail. This is formulated based on the leading-logarithmic renormalization equation for the electron structure function and it provides a photon shower along the initial e+-. The main interest in the present work is to test the reliability of the generator to describe a process accompanyin

P. H Chankowski, S. Pokorski

We re-examine the possible magnitude of the supersymmetric contribution to $R_b$ with imposed all available phenomenological constraints and demanding good quality of the global fit to the precision electroweak data. For low $\tanβ$ we find a new region of the parameter space, with $M_2\approx |μ|$ and $μ<0$ where $R_b$ remains large, $\sim0.2180$ even for t

Zhi-jian Tao

We investigate an alternative seesaw mechanism for neutrino mass generation. Neutrino mass is generated at loop level but the basic concept of usual seesaw mechanism is kept. One simple model is constructed to show how this mechanism is realized. The applications of this seesaw mechanism at weak scale to cosmology and neutrino physics are discussed.

Vladimir S. Mashkevich

This paper is a continuation of the papers [gr-qc/9409010, gr-qc/9505034]. A revision of the Einstein equation shows that its dynamic incompleteness, contrary to a popular opinion, cannot be circumvented by so-called coordinate conditions. Gravidynamics, i.e., dynamics for gravitational potentials $g_{μν}$ is advanced, which differs from geometrodynamics of

A. Pajitnov

For a Morse map $f:M\to S^1$ Novikov [11] has introduced an analog of Morse complex, defined over the ring $\ZZZ[[t]][t^{-1}]$ of integer Laurent power series. Novikov conjectured, that generically the matrix entries of the differentials in this complex are of the form $\sum_ia_it^i$, where $a_i$ grow at most exponentially in $i$. We prove that for any given

E. D. Bauer, F. Bridges, C. H. Booth, J. B. Boyce

We have studied the local structure around Co in YBa$_2$(Cu$_{1-x}$Co$_x$)$_3$O$_{7-δ}$ thin films with three different concentrations: x=0.07, 0.10, 0.17, and in a PrBa$_2$(Cu$_{1-x}$Co$_x$)$_3$O$_{7-δ}$ thin film of concentration x=0.05 using the X-ray Absorption Fine Structure (XAFS) technique. Data were collected at the Co $K$-edge with polarizations bot

Mangal C. Mahato, T. P. Pareek, A. M. Jayannavar

Several physical models have recently been proposed to obtain unidirectional motion of an overdamped Brownian particle in a periodic potential system. The asymmetric ratchetlike form of the periodic potential and the presence of correlated nonequilibrium fluctuating forces are considered essential to obtain such a macroscopic motion in homogeneous systems. I

J. Leandri, Y. Leroyer, S. V. Meshkov, Y. Meurdesoif

We study the planar antiferromagnetic Heisenberg model on a decorated hexagonal lattice, involving both classical spins (occupying the vertices) and quantum spins (occupying the middle of the links). This study is motivated by the description of a recently synthesized molecular magnetic compound. First, we trace out the spin 1/2 degrees of freedom to obtain

Giorgio Parisi

We show that the predictions of spontaneously broken replica symmetry are in perfect agreement with the recent rigorous results obtained by Newman and Stein.

O. Heinonen, M. I. Lubin, M. D. Johnson

The fractional quantum Hall effect (FQHE) occurs at certain magnetic field strengths B*(n) in a two-dimensional electron gas of density n at strong magnetic fields perpendicular to the plane of the electron gas. At these magnetic fields strengths, the system is incompressible, i.e., there is a finite cost in energy for creating charge density fluctuations in

S. Zaroubi, A. Dekel, Y. Hoffman, T. Kolatt

The power spectrum (PS) of {\it mass} density fluctuations, independent of ``biasing&#34;, is estimated from the Mark3 Catalog of Peculiar Velocities of galaxies using Bayesian statistics. A parametric model is assumed for the PS, and the free parameters are determined by maximizing the posterior probability of the model given the data. The method has been t

A. Mathieu, H. Dejonghe

A family of triaxial Stäckel potential-density pairs is introduced. With the help of a Quadratic Programming method, a linear combination of potential-density pairs of this family which fits a given projected density distribution can be built. This deprojection strategy can be used to model the potentials of triaxial elliptical galaxies with or without dark

M. P. Hobson, Joao Magueijo

We investigate the effects of finite sky coverage on the spectral resolution $Δ\ell$ in the estimation of the CMBR angular power spectrum $C^{\ell}$. A method is developed for obtaining quasi-independent estimates of the power spectrum, and the cosmic/sample variance of these estimates is calculated. The effect of instrumental noise is also considered for pr

Pieter van Dokkum, Marijn Franx

We present results on the Fundamental Plane of early-type galaxies in the rich cluster CL 0024+16 at z=0.391. The galaxies satisfy a tight Fundamental Plane relation which is similar to that at low redshift. The scatter is 15 % in log re. The data show that massive early-type galaxies existed at z=0.4. The evolution of the M/L ratio is derived from the Funda

Mauro Giavalisco, Charles C. Steidel, F. Duccio Macchetto

We present HST images of star-forming galaxies at redshifts z>3. These galaxies have been color selected for having a Lyman discontinuity in the otherwise flat (in f_νunits) UV spectra of unreddened star formation. The spectroscopic confirmation of these z>3 galaxies is reported in a companion paper (Steidel et al. 1996). The HST images probe the rest-frame

Paolo Padoan, Bernard J. T. Jones, AAke Nordlund

Lada et al. (1994) have described a method for studying the distribution of dust in dark clouds using infrared imaging surveys. In particular they show that the method provides some information about the structure of the gas (dust) on scales smaller than their resolution. In the present work we clarify the nature of the information provided by their method.

Paolo Padoan, Raul Jimenez

We extend our previous method to determine globular cluster ages using the luminosity function (Jimenez \& Padoan 1996). We show that the luminosity function depends on both age and distance modulus and that it is possible to distinguish between the two. This method provides at the same time independent determinations of distance and age of a GC by simply co

Rainer Fuhrmann, Fernando Torres

We study arithmetical and geometrical properties of {\it maximal curves}, that is, curves defined over the finite field $\mathbb F_{q^2}$ whose number of $\mathbb F_{q^2}$-rational points reachs the Hasse-Weil upper bound. Under a hypothesis on non-gaps at rational points we prove that maximal curves are $\mathbb F_{q^2}$-isomorphic to $y^q+y=x^m$ for some $

Laurent Manivel

We prove a general vanishing theorem for the cohomology of products of symmetric and skew-symmetric powers of an ample vector bundle on a smooth complex projective variety. Special cases include an extension of classical theorems of Griffiths and Le Potier to the whole Dolbeault cohomology, and an answer to a problem raised by Demailly. An application to deg

Scott Nollet

In this paper we show that the Hilbert scheme $H(3,g)$ of locally Cohen-Macaulay curves in $\Pthree$ of degree three and genus $g$ is connected. In contrast to $H(2,g)$, which is irreducible, $H(3,g)$ generally has many irreducible components (roughly $-g/3$ of them). To show connectedness, we classify the curves (giving particular attention to the triple li

Heinz-Olaf Müller, Andreas Hädicke, Ulrik Hanke, K. A. Chao

The ``orthodox theory&#39;&#39; of a single electron double junction is dealt with. It is shown that the stationary solution of the underlying master equation allows the construction of any time-dependent solution in terms of orthogonal polynomials. The approach pays off if the stationary solution becomes simple. Two special cases are considered. We use the

Jeffrey A. Harvey

These notes present a pedagogical introduction to magnetic monopoles and exact electromagnetic duality in supersymmetric gauge theories. They are based on lectures given at the 1995 Trieste Summer School in High Energy Physics and Cosmology and at the 1995 Busstepp Summer School at Cosener&#39;s House.

Jerzy Jurkiewicz, Maciej A. Nowak, Ismail Zahed

We use a chiral random matrix model to investigate the effects of massive quarks on the distribution of eigenvalues of QCD inspired Dirac operators. Kalkreuter&#39;s lattice analysis of the spectrum of the massive (hermitean) Dirac operator for two colors and Wilson fermions is shown to follow from a cubic equation in the quenched approximation. The quenched

G. Papadopoulos, P. K. Townsend

We present the magnetic duals of Güven&#39;s electric-type solutions of D=11 supergravity preserving $1/4$ or $1/8$ of the D=11 supersymmetry. We interpret the electric solutions as $n$ orthogonal intersecting membranes and the magnetic solutions as $n$ orthogonal intersecting 5-branes, with $n=2,3$; these cases obey the general rule that $p$-branes can self

W. A. Sabra

The duality symmetry group of the cosets ${\textstyle SU(n,1)\over \textstyle SU(n)\otimes U(1)}$, which describe the moduli space of a two-dimensional subspace of an orbifold model with $(n-1)$ complex Wilson lines moduli, is discussed. The full duality group and its explicit action on the moduli fields are derived.

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

The $|ΔI|=1/2$ rule in non-leptonic decays of hyperons can be naturally understood by postulating a priori mixed physical hadrons, along with the isospin invariance of the responsible transition operator. It is shown that this operator can be identified with the strong interaction Yukawa hamiltonian. The experimental amplitudes are well reproduced.

M. Caffo, H. Czyz, E. Remiddi

We present simple analytic expressions for the distributions of the Bhabha scattering process with emission of one hard photon, including weak boson exchanges, and with longitudinal polarization of the initial electron. The results from the Monte Carlo generator BHAGEN-1PH, based on these expressions, are presented and compared, for the unpolarized case, wit

S. A. Abel

It is argued that singlet extensions of the MSSM at the weak scale are indicative of either gauged-$R$ symmetry or target space duality in a string effective action at the Planck scale. The criteria used are satisfactory primordial nucleosynthesis, absence of fine-tuning, and absence of cosmological problems such as domain walls. Models which have a global d

G. E. Volovik

The bound states of fermions in cores of quantized vortices in superconductors and Fermi superfluids and their influence on the vortex dynamics are discussed. The role of the spectral flow of the fermions through the gap nodes is emphasized.

Ulf H. Danielsson, Gabriele Ferretti, Bo Sundborg

We study the low energy effective theory describing the dynamics of D-particles. This corresponds to the quantum mechanical system obtained by dimensional reduction of $9+1$ dimensional supersymmetric Yang-Mills theory to $0+1$ dimensions and can be interpreted as the non relativistic limit of the Born-Infeld action. We study the system of two like-charged D

Shuhei Mano, Hisao Suzuki, Eiichi Takasugi

Analytic solutions of the Teukolsky equation in Kerr geometries are presented in the form of series of hypergeometric functions and Coulomb wave functions. Relations between these solutions are established. The solutions provide a very powerful method not only for examining the general properties of solutions and physical quantities when they are applied to,

C. -A. Piguet, D. F. Wang, C. Gruber

In this work, a multichannel Kondo lattice model is studied in the thermodynamic limit. The conduction band is described by a constant hopping amplitude between any pair of lattice sites. For this system, we have obtained the exact thermodynamical properties and the ground state energies. In the limit of strong interaction between the electrons and the impur

T. Kubota

The Rubakov-Callan effect is reexamined by considering the gravitational effects caused by the heavy monopole mass. Assuming that the Higgs vacuum expectation value is as large as (or larger than) the Planck mass, we show that the calculational scheme of Rubakov and Callan may be extended in the presence of curved background field. It is argued that the dens

Masamichi Kojima, Nobuyoshi Ohta

Using a collective field method, we obtain explicit solutions of the generalized Calogero-Sutherland models that are characterized by the roots of the classical groups $B_N$ and $C_N$. Starting from the explicit wave functions for $A_{N-1}$ type expressed in terms of the singular vectors of the $W_N$ algebra, we give a systematic method to construct wave fun

J. Twamley

We compute the Bures distance between two thermal squeezed states and deduce the Statistical Distance metric. By computing the curvature of this metric we can identify regions of parameter space most sensitive to changes in these parameters and thus lead to optimum detection statistics.

M. S. Marinov, Bilha Segev

Asymptotic time evolution of a wave packet describing a non-relativistic particle incident on a potential barrier is considered, using the Wigner phase-space distribution. The distortion of the trasmitted wave packet is determined by two time-like parameters, given by the energy derivative of the complex transmission amplitude. The result is consistent with

G. E. Brown, M. Buballa, M. Rho

The recent discussions by Kocić and Kogut on the nature of the chiral phase transition are reviewed. The mean-field nature of the transition suggested by these authors is supported in random matrix theory by Verbaarschot and Jackson which reproduces many aspects of QCD lattice simulations. In this paper, we point out physical arguments that favor a mean-fiel

R. Bijker, A. Leviatan

We study the strong couplings of the nucleon and delta resonances in a collective model. In the ensuing algebraic treatment we derive closed expressions for decay widths which are used to analyze the experimental data for strong decays into the pion and eta channels.

Attila Csoto, Steven Karataglidis

The Li-7(p,gamma_0)Be-8 reaction is studied in a microscopic cluster model. All relevant subsystem properties are well reproduced. The calculated astrophysical S factor is in good agreement with the experimental data, although some M1 strength is missing in the 1+;1 resonance region. There is no contribution from the 1+;0 state. We estimate an M1 strength of

Pavlos Protopapas, Abraham Klein, Niels R. Walet

In two previous papers, the Kerman-Klein-Donau-Frauendorf (KKDF) model was used to study rotational bands of odd deformed nuclei. Here we describe backbending for odd nuclei using the same model. The backbending in the neighboring even nuclei is described by a phenomenological two band model, and this core is then coupled to a large single-particle space, as

L. Zamick, D. C. Zheng

We consider several topics concerning static magnetic dipole and electric quadrupole moments ($μ$ and $Q$) as signatures of the onset of nuclear collectivity. Having previously noted that in $^{50}\mbox{Cr}$ there is an abrupt change of sign in $Q$ of yrast states with $J^π=10^+, 12^+$, and $14^+$ relative to lower $J$ states, we discuss whether these states

Denny H. Leung

It is shown that the tensor product $JH\epten JH$ fails Pełczńyski&#39;s property (u). The proof uses a result of Kwapień and Pełczńyski on the main triangle projection in matrix spaces.

E. Alvarez, J. L. F. Barbon, J. Borlaf

The T-duality transformations between open and closed superstrings in different D-manifolds are generalized to curved backgrounds with commuting isometries. We address some global aspects like the occurrence of orientifold boundaries in general sigma models, higher genus world sheets, and the case of non-compact isometries. The various world volume effective

Pierre Mathieu, Gerard Watts

It has been known for some time that the (1,3) perturbations of the (2k+1,2) Virasoro minimal models have conserved currents which are also singular vectors of the Virasoro algebra. This also turns out to hold for the (1,2) perturbation of the (3k+-1,3) models. In this paper we investigate the requirement that a perturbation of an extended conformal field th

A. Bassetto, L. Griguolo

We show that the replacement of the ``instantaneous&#39;&#39; &#39;t Hooft&#39;s potential with the causal form suggested by equal time canonical quantization in light-cone gauge, which entails the occurrence of negative probability states, does not change the bound state spectrum when the difference is treated as a single insertion in the kernel.

Abhay Ashtekar, Jerzy Lewandowski

Over the past five years, there has been significant progress on the problem of quantization of diffeomorphism covariant field theories with {\it local} degrees of freedom. The absence of a background space-time metric in these theories gives rise to a host of conceptual and technical difficulties because most of the familiar methods from axiomatic, construc

Ulf H. Danielsson, Pär Stjernberg

In this paper we investigate how various equivalences between effective field theories of $N=2$ SUSY Yang-Mills theory with matter can be understood through Higgs breaking, i.e. by giving expectation values to squarks. We give explicit expressions for the flat directions for a wide class of examples.

N. Sh. Izmailian

The spin - 3/2 Ising model on a square lattice is investigated. It is shown that this model is reducible to an eight - vertex model on a surface in the parameter space spanned by coupling constants J, K, L and M. It is shown that this model is equivalent to an exactly solvable free fermion model along two lines in the parameter space.

J. C. Breckenridge, D. A. Lowe, R. C. Myers, A. W. Peet

A seven parameter family of five-dimensional black hole solutions depending on mass, two angular momenta, three charges and the asymptotic value of a scalar field is constructed. The entropy is computed as a function of these parameters both from the Bekenstein-Hawking formula and from the degeneracies of the corresponding D-brane states in string theory. Th

J. W. F. Valle

We discuss some of the signatures associated with extensions of the Standard Model related to the neutrino and electroweak symmetry breaking sectors, with and without supersymmetry. The topics include a basic discussion of the theory of neutrino mass and the corresponding extensions of the Standard Model that incorporate massive neutrinos; an overview of the

B. W. Harris, J. F. Owens

Fully differential heavy quark contributions to the photon structure functions in deeply inelastic scattering are computed in next-to-leading order QCD, including both the direct and resolved contributions. A variety of distributions are presented and discussed. Several of the distributions show marked differences between the resolved and direct cases due pr

M. Gluck, S. Kretzer, E. Reya

Charm production as related to the determination of the strange sea density in deep inelastic charged current processes is studied predominantly in the framework of the $\overline{\rm{MS}}$ fixed flavor factorization scheme. Perturbative stability within this formalism is demonstrated. The compatibility of recent next-to-leading order strange quark distribut

R. Baier, M. Dirks, O. Kober

We discuss chiral theories of constituent quarks interacting with bosons at high temperatures. In the chirally symmetric phase we demonstrate by applying functional methods the presence of effective anomalous couplings for e.g. $πσ\to γγ, ~ γ\to πππσ, ~K K \to πππσ$, etc., as they have recently been discussed by Pisarski.

D. de Florian, L. N. Epele, H. Fanchiotti, C. A. García Canal

We have computed semi-inclusive spin asymmetries for proton and deuteron targets including next to leading order (NLO) QCD corrections and contributions coming from the target fragmentation region. These corrections have been estimated using NLO fragmentation functions, parton distributions and also a model for spin dependent fracture functions which is prop

T. S. Biro

It is unlikely to reach at high temperatures the state which is used as the starting point of DCC formation in the quenched approximation. The chiral symmetry is restored in the linear sigma model by Goldstone modes (pions), because such isospin-p-wave states carry more entropy. In this paper we estimate this effect of isospin-angular motion in the mean fiel

Damir Becirevic

The behavior of the $\bpi$ form factors in the entire physical range is examined in a model independent way. Unitarity bounds are further constrained by the lattice results (APE). From this analysis, we obtain $f^{+}(0) = 0.38 \pm .03$ if the $B^{*}$-pole dominance behavior is assumed. However, to get the information on the behavior of the form factor $f^{+}

R. Casalbuoni, A. Deandrea, S. De Curtis, D. Dominici

An effective lagrangian describing a strong interacting electroweak sector is considered. It contains new vector and axial-vector resonances all degenerate in mass and mixed with $W$ and $Z$. The model, for large mass of these degenerate gauge bosons, becomes identical to the standard model in the classical limit of infinite Higgs mass. The limits on the par

G. Cynolter, A. Bodor, G. Pocsik

We replace the standard model scalar doublet by a doublet of vector fields and generate masses by dynamical symmetry breaking. Oblique radiative corrections are small if the new vector bosons ($ B^+$, $ B^0 $) are heavy. In this note it is shown that the model has a low momentum scale and above $ Λ\simeq 2 $ TeV it does not respect the perturbative unitarity