August 1996 arXiv papers — page 10

Bohdan Grzadkowski, Zenro Hioki

In order to observe a signal of possible CP violation in top-quark couplings, we have studied energy correlation of the final leptons in $e^+e^-\to t\bar{t} \to \ell^+\ell^-X / \ell^\pm X$ at future linear colliders. Applying the recently-proposed optimal method, we have compared the statistical significances of CP-violation-parameter determination using dou

Hideo Mabuchi

I propose a quantum trajectories approach to parametric identification of the effective Hamiltonian for a Markovian open quantum system, and discuss an application motivated by recent experiments in cavity quantum electrodynamics. This example illustrates a strategy for quantum parameter estimation that efficiently utilizes the information carried by correla

Karin Berndl, Stefan Teufel

In Section 3 of his paper (N. Gisin, Phys. Lett. A 210 (1996) 151), Gisin argues that a ``careless application of generalized quantum measurements can violate Bell's inequality even for mixtures of product states.'' However, the observed violation of the CHSH inequality is not in fact due to the application of generalized quantum measurements, bu

Sergei V. Shabanov

A method of path integral construction without gauge fixing in the holomorphic representation is proposed for finite-dimensional gauge models. This path integral determines a manifestly gauge-invariant kernel of the evolution operator.

Igor Aranson, Michel Assenheimer, Victor Steinberg, Lev S. Tsimring

The spiral core instability, observed in large aspect ratio Rayleigh-Benard convection, is studied numerically in the framework of the Swift-Hohenberg equation coupled to a large-scale flow. It is shown that the instability leads to non-trivial core dynamics and is driven by the self-generated vorticity. Moreover, the recently reported transition from spiral

S. Ray, J. Shamanna, T. T. S. Kuo

An isospin lattice-gas model, which is a spin-1 Ising model, is employed to investigate the liquid-gas phase transition in asymmetric nuclear matter. We consider nuclear matter as a lattice where each lattice site can be either empty or occupied by a proton or a neutron, with a nearest-neighbor interaction among the nucleons. With the Bragg-Williams mean fie

Dirk H. Rischke

Hydrodynamics is applied to describe the dynamics of relativistic heavy-ion collisions. The focus of the present study is the influence of a possible (phase) transition to the quark-gluon plasma in the nuclear matter equation of state on collective observables, such as the lifetime of the system and the transverse directed flow of matter. It is shown that su

Xuemin Jin, B. K. Jennings

The modified quark-meson coupling model, which features a density dependent bag constant and bag radius in nuclear matter, is checked against the EMC effect within the framework of dynamical rescaling. Our emphasis is on the change in the average bag radius in nuclei, as evaluated in a local density approximation, and its implication for the rescaling parame

S. Chattopadhyay

Within the framework of stochastic one-body approach a simulation procedure to study the Vlasov dynamics for fermi system on phase space lattice is presented. To deal with fermions on lattice, the phase cell occupancy factors are taken to be either 1 or 0 in accordance with the Pauli exclusion principle. This has significant implications. First, the dynamica

T. S. Biro, J. Zimanyi

The relativistic mean field model, the Zimányi - Moszkowski (ZM) Lagrangian describes nuclear matter and stable finite nuclei even in the non-relativistic limit. It fails, however, to predict the correct non-relativistic spin-orbit (SO) coupling. In this paper we improve on this matter by an additional tensor coupling analogous to the anomalous gyromagnetic

D. Horn, G. C. Ball, D. R. Bowman, W. G. Davies

We report the first experimental observation of the pionic fusion of two heavy ions. The 12C(12C,24Mg)pi0 and 12C(12C,24Na)pi+ cross sections have been measured to be 208 +/- 38 and 182 +/- 84 picobarns, respectively, at E_cm = 137 MeV. This cross section for heavy-ion pion production, at an energy just 6 MeV above the absolute energy-conservation limit, con

Serdar Ogut, Karin M. Rabe

For the orthorhombic intermetallic semiconductor Al$_2$Ru, the bandstructure, valence charge density, zone center optical phonon frequencies, and Born effective charge and electronic dielectric tensors are calculated using variational density functional perturbation theory with {\em ab initio} pseudopotentials and a plane wave basis set. Good agreement is ob

G. W. Gibbons, P. Rychenkova

We use the HyperKähler quotient of flat space to obtain some monopole moduli space metrics in explicit form. Using this new description, we discuss their topology, completeness and isometries. We construct the moduli space metrics in the limit when some monopoles become massless, which corresponds to non-maximal symmetry breaking of the gauge group. We also

T. E. Clark, S. T. Love

The Wilson (exact) renormalization group equations are used to determine the evolution of a general low energy N=1 supersymmetric action containing a U(1) gauge vector multiplet and a neutral chiral multiplet. The effective theory evolves towards satisfying a fixed relation where the Kähler potential and effective gauge coupling are obtained from a N=2 super

B. Julia, H. Nicolai

General Relativity reduced to two dimensions possesses a large group of symmetries that exchange classical solutions. The associated Lie algebra is known to contain the affine Kac-Moody algebra $A_1^{(1)}$ and half of a real Witt algebra. In this paper we exhibit the full symmetry under the semi-direct product of $\Lie{A_1^{(1)}}$ by the Witt algebra $\Lie{\

Y. S. Kim

It is pointed out that there are gauge-dependent and gauge-independent spinors within the little-group framework for internal space-time symmetries of massless particles. It is shown that two of the $SL(2,c)$ spinors are invariant under gauge transformations while the remaining two are not. The Dirac equation contains only the gauge-invariant spinors leading

K. S. McFarland

The relevance of existing $νN$ deep inelastic scattering data to models containing a leptophobic neutral vector boson is discussed. It is shown that this neutral current data is in good agreement with the Standard Model and disfavors such a leptophobic boson.

B. Faid, G. L. Fogli, E. Lisi, D. Montanino

We propose to study possible signals of just-so oscillations in new-generation solar neutrino experiments by separating the events detected when the earth is nearest to the sun (perihelion $\pm$~3~months) from those detected when the earth is farthest from the sun (aphelion $\pm$~3~months). We introduce a solar model independent near-far asymmetry, which is

Stefano Catani

I review the basic idea of $k_{\perp}$-factorization and its relation to collinear factorization. Theoretical results in resummed perturbation theory are summarized and the example of the heavy-flavour structure functions is explicitly considered. Using these results one can investigate the small-$x$ behaviour of quantities that are independent of the non-pe

M. C. Gonzalez-Garcia, S. F. Novaes

We investigate the effects induced by excited leptons at the one-loop level in the observables measured on the $Z$ peak at LEP. Using a general effective Lagrangian approach to describe the couplings of the excited leptons, we compute their contributions to both oblique parameters and $Z$ partial widths. Our results show that the new effects are comparable t

W. Buchmuller, M. Plumacher

In theories where $B-L$ is a spontaneously broken local symmetry, the cosmological baryon asymmetry can be generated by the out-of-equilibrium decay of heavy Majorana neutrinos. We study this mechanism assuming a similar pattern of mixings and masses for leptons and quarks, as suggested by SO(10) unification. This implies that $B-L$ is broken at the unificat

V. Berezinsky, Anjan S. Joshipura, J. W. F. Valle

The discrete R-parity ($R_P$) usually imposed on the Supersymmetric (SUSY) models is expected to be broken at least gravitationally. If the neutralino is a dark matter particle its decay channels into positrons, antiprotons and neutrinos are severely constrained from astrophysical observations. These constraints are shown to be violated even for Planck-mass-

W. Lee, D. Weingarten

We evaluate the valence approximation to the mass of scalar quarkonium for a range of different parameters. Our results strongly suggest that the infinite volume continuum limit of the mass of $s\overline{s}$ scalar quarkonium lies well below the mass of $f_J(1710)$. The resonance $f_0(1500)$ appears to the best candidate for $s\overline{s}$ scalar quarkoniu

Don Weingarten

Valence approximation glueball mass and decay calculations support the identification of $f_J(1710)$ as the lightest scalar glueball. An alternate glueball candidate is $f_0(1500)$. I present evidence for the identification of $f_0(1500)$ as $s\overline{s}$ quarkonium.

R. C. Brower, S. Huang, J. W. Negele, A. Pochinsky

Preliminary results are presented in our program to calculate low moments of structure functions for the proton and neutron on a $24^3\times32$ lattice at $β=6.2$. A comparison is made for a variety of smeared nucleon sources and preliminary results for the calculation of the nucleon tensor charge are presented.

W. Bietenholz, R. Brower, S. Chandrasekharan, U. -J. Wiese

We describe a number of aspects in our attempt to construct an approximately perfect lattice action for QCD. Free quarks are made optimally local on the whole renormalized trajectory and their couplings are then truncated by imposing 3-periodicity. The spectra of these short ranged fermions are excellent approximations to continuum spectra. The same is true

O. Philipsen, M. Teper, H. Wittig

We present results for the masses of the low-lying states with quantum numbers $0^{++}$, $2^{++}$ and $1^{--}$ as well as Polyakov line correlations in the Higgs and confinement regions of the 3d SU(2) Higgs model. In the confinement phase we find a dense spectrum of bound states approximately split into two disjoint sectors. One consists of W-balls nearly i

S. Fischer, A. Frommer, U. Glaessner, S. Guesken

A parallelizable SSOR preconditioning scheme for Krylov subspace iterative solvers in lattice QCD applications involving Wilson fermions is presented. In actual Hybrid Monte Carlo and quark propagator calculations it helps to reduce the number of iterations by a factor of 2 compared to conventional odd-even preconditioning. This corresponds to a gain in cpu-

H. R. Fiebig, A. Mihaly, H. Markum, K. Rabitsch

Starting from the meson-meson Green function in 3+1 dimensional quenched lattice QCD we calculate potentials between heavy-light mesons for various light-quark mass parameters. For the valence quarks we employ the staggered scheme. The resulting potentials turn out to be short ranged and attractive. A comparison with a tadpole improved action for the gauge f

S. Collins, U. M. Heller, J. Sloan, J. Shigemitsu

We present results for the spectrum and decay constants of B mesons from NRQCD using dynamical configurations at $β=5.6$ with two flavours of staggered fermions. The light quarks are generated using the Clover action with tadpole improvement.

Rudolf Burkhalter

We define a fixed point action in two-dimensional lattice CP^{N-1} models. The fixed point action is a classical perfect lattice action, which is expected to show strongly reduced cut-off effects in numerical simulations. Furthermore, the action has scale invariant instanton solutions, which enables us to define a topological charge without topological defec

Yasumichi Aoki

We study the finite-temperature phase transition of the four-dimensional SU(2) gauge-Higgs model for intermediate values of the Higgs boson mass in the range $50 \lsim m_H \lsim 100$GeV on a lattice with the temporal lattice size $N_t=2$. The order of the transition is systematically examined using finite size scaling methods. Behavior of the interface tensi

K. S. McFarland

We report the results of a study of electroweak parameters from observations of neutral-current $ν$N deeply inelastic scattering in the CCFR detector at the FNAL Tevatron Quadrupole Triplet neutrino beam. An improved extraction of the weak mixing angle in the on-shell renormalization scheme, incorporating additional data and with an improved technique for co

R. Mansouri, M. Khorrami

A distributional method to solve the Einstein's field equations for thin shells is formulated. The familiar field equations and jump conditions of Darmois-Israel formalism are derived. A carefull analysis of the Bianchi identities shows that, for cases under consideration, they make sense as distributions and lead to jump conditions of Darmois-Israel for

Roberto Iengo, Giancarlo Jug

We investigate the phenomenon of the decay of a supercurrent due to the zero-temperature quantum tunneling of vortices from the edge in a thin superconducting film in the absence of an external magnetic field. An explicit formula is derived for the tunneling rate of vortices, which are subject to the Magnus force induced by the supercurrent, through the Coul

I. Dana, E. Eisenberg, N. Shnerb

The phenomenon of quantum antiresonance (QAR), i.e., exactly periodic recurrences in quantum dynamics, is studied in a large class of nonintegrable systems, the modulated kicked rotors (MKRs). It is shown that asymptotic exponential localization generally occurs for $η$ (a scaled $\hbar$) in the infinitesimal vicinity of QAR points $η_0$. The localization le

Kang-Hun Ahn, K. J. Chang

We present a microscopic theory of skyrmion and antiskyrmion excitations in fractional quantum Hall systems, and calculate in an analytical fashion their excitation energies. From the calculated net spins at various fractional filling factors, we find the magnetic field dependence of the spin polarization of the skyrmion-condensated state.

David Milward, Karsten Konrad, Holger Maier, Manfred Pinkal

The CLEARS (Computational Linguistics Education and Research for Semantics) tool provides a graphical interface allowing interactive construction of semantic representations in a variety of different formalisms, and using several construction methods. CLEARS was developed as part of the FraCaS project which was designed to encourage convergence between diffe

R. E. Pudritz, C. D. Wilson, J. E. Carlstrom, O. P. Lay

Continuum emission at 220 and 355 GHz from the prototype Class 0 source VLA 1623 has been detected using the JCMT-CSO interferometer. Gaussian fits to the data place an upper limit of 70 AU on the half-width half-maximum radius of the emission, which implies an upper limit of ~175 AU for the cutoff radius of the circumstellar disk in the system. In the conte

Dennis Zaritsky, Hans-Walter Rix

We present a measurement of lopsidedness for the stellar disks of 60 field spiral galaxies in terms of the azimuthal m=1 Fourier amplitude, A_1, of the stellar light. We conjecture that this lopsidedness is caused by tidal interactions and calculate an UPPER limit on the accretion rate of small galaxies. We exploit the correlation between lopsidedness and ph

Gary Steigman

Primordial nucleosynthesis is inevitable during the early evolution of an expanding universe filled with radiation and matter (baryons). However, the precise abundance yields depend sensitively on the baryon density, the radiation content and the early expansion rate. For ``standard" big bang nucleosynthesis (SBBN) only D, $^3$He, $^4$He and $^7$Li are p

H. Domgorgen, M. Dahlem, R. -J. Dettmar

VLA HI observations of the dwarf irregular galaxy NGC 2188 show that the gas and stars have spatial distributions which are substantially different. One end of the optical disk is strongly gas deficient, while neutral gas extends into the halo over distances of more than 2 kpc from the midplane. This and the peculiar velocity field suggest that NGC 2188 is a

M. Kissler-Patig, S. Kohle, M. Hilker, T. Richtler

We studied the properties of the globular cluster systems of five early--type galaxies in the Fornax galaxy cluster: NGC 1374, NGC 1379, NGC 1387, NGC 1427, and the central giant elliptical NGC 1399. From the investigation of their number of globular clusters, specific frequency, color distribution, surface density profile, and spatial distribution, we concl

R. Bender, R. P. Saglia, B. Ziegler

We review the observational evidence showing that luminous cluster elliptical galaxies are old stellar systems, undergoing mostly passive stellar evolution up to redshift $z\approx 1$, with approximate coeval epoch of formation. This scenario is supported by observations of local early--types, collected by 2m -- 4m class telescopes, and fits the recently gai

Richard Ellis

I review progress in understanding the evolution of normal field and cluster galaxies through the combination of HST imaging and ground-based spectroscopy. These data suggest that the bulk of the star formation producing the present-day galaxy population occurred at accessible redshifts, $z<$2. Furthermore, a surprising amount of the detailed processing that

J. Bednarz, M. Ostrowski

The acceleration time scale for the process of first-order Fermi acceleration in relativistic shock waves with oblique magnetic field configurations is investigated by the method of Monte Carlo particle simulations. We demonstrate the presence of correlation between the particle energy gain at interaction with the shock and the respective time elapsed since

G. A. Mamon, V. Banchet, M. Tricottet, D. Katz

The extragalactic applications of NIR surveys are summarized with a focus on the ability to map the interstellar extinction of our Galaxy. Very preliminary extraction of galaxies on a set of 180 consecutive images is presented, and the results illustrate some of the pitfalls in attempting an homogeneous extraction of galaxies from these wide-angle and shallo

Gary Mamon

The DENIS and 2MASS near infrared surveys are presented. Their applications in extragalactic astronomy and cosmology are listed. The prospects for a rapid spectroscopic followup survey of a near infrared selected sample of nearly $10^5$ galaxies are illustrated with Monte-Carlo simulations.

Georg G. Raffelt

In a supernova (SN) core during infall and after collapse, neutrinos are trapped by their interactions with nucleons. For the axial-vector current interactions it is not enough to include static particle-particle correlations. Even the single-nucleon spin autocorrelation reduces the scattering cross section dramatically. Therefore, the dynamical structure of

S. R. Folkes, O. Lahav, S. J. Maddox

We present a method for automated classification of galaxies with low signal-to-noise (S/N) spectra typical of redshift surveys. We develop spectral simulations based on the parameters for the 2dF Galaxy Redshift Survey, and with these simulations we investigate the technique of Principal Component Analysis when applied specifically to spectra of low S/N. We

F. W. Stecker, O. C. de Jager

We present a new calculation of the intergalactic $γ$-ray pair-production absorption coefficient as a function of both energy and redshift up to the redshift of 3C279, z = 0.54. In reexamining this problem, we make use of new observational data on the intergalactic infrared radiation field (IIRF), together with recent theoretical models of the galactic spect

Hyesung Kang, Jörg P. Rachen, Peter L. Biermann

Motivated by the suggestion of Kang, Ryu \& Jones (1996) that particles can be accelerated to high energies via diffusive shock acceleration process at the accretion shocks formed by the infalling flow toward the clusters of galaxies, we have calculated the expected particle flux from a cosmological ensemble of clusters. We use the observed temperature distr

Masahiro Nagashima, Naoteru Gouda

The effects of spatial correlations of density fluctuations on merger histories of dark matter haloes (so-called `{\it merger trees}&#39;) are analysed. We compare the mass functions of dark haloes derived by a new method for calculating merger trees, that proposed by Rodrigues \& Thomas (RT), with those given by other methods such as the Block model, the Pr

Joshua A. Frieman

On-going projects to discover Type Ia supernovae at redshifts z = 0.3 - 1, coupled with improved techniques to narrow the dispersion in SN Ia peak magnitudes, have renewed the prospects for determining the cosmic deceleration parameter q_0. We estimate the expected uncertainty in the Hubble diagram determination of q_0 due to weak lensing by structure in the

Dongsu Ryu, Hyesung Kang

During the formation of the large scale structure of the Universe, matter accretes onto high density peaks. Accreting collisionless dark matter (DM) forms caustics around them, while accreting collisional baryonic matter (BM) forms accretion shocks. The properties of the accreting matter depend upon the power spectrum of the initial perturbations on a given

M. Giusti, J. Heintz, K. Hägele, J. E. Morais

We introduce a subexponential algorithm for geometric solving of multivariate polynomial equation systems whose bit complexity depends mainly on intrinsic geometric invariants of the solution set. From this algorithm, we derive a new procedure for the decision of consistency of polynomial equation systems whose bit complexity is subexponential, too. As a byp

Yuhai Tu, G. Grinstein, M. A. Muñoz

We show that certain critical exponents of systems with multiplicative noise can be obtained from exponents of the KPZ equation. Numerical simulations in 1d confirm this prediction, and yield other exponents of the multiplicative noise problem. The numerics also verify an earlier prediction of the divergence of the susceptibility over an entire range of cont

Hirosi Ooguri, Cumrun Vafa

We investigate quantum corrections to the moduli space for hypermultiplets for type IIA near a conifold singularity. We find a unique quantum deformation based on symmetry arguments which is consistent with a recent conjecture. The correction can be interpreted as an infinite sum coming from multiple wrappings of the Euclidean D-branes around the vanishing c

L. A. Abramyan, V. I. Berezhiani, A. P. Protogenov

We study the solutions of the equations of motion in the gauged (2+1)-dimensional nonlinear Schrödinger model. The contribution of Chern-Simons gauge fields leads to a significant decrease of the critical power of self-focusing. We also show that at appropriate boundary conditions in the considered model there exists a regime of turbulent motions of hydrodyn

E. G. D. Cohen

Lecture given at the International Meeting ``Boltzmann&#39;s Legacy - 150 Years after his Birth&#39;&#39;, organized by the Accademia Nazionale dei Lincei, 25 - 28 May 1994, in Rome, to be published in: ``Atti dell&#34;Accademia Nazionale dei Lincei&#39;&#39;, 1997.

Xuemin Jin

The external-field method has been used extensively in the QCD sum-rule approach to explore various hadron static properties. In the traditional formalism of this method, the transitions from the ground state hadron to excited states are not exponentially suppressed relative to the ground state term and thus contaminate the ground state hadron property to be

I. M. Barbour, J. B. Kogut, S. E. Morrison

We compare the chemical potential associated with the onset of non-zero baryon number density on $6^4$ and $8^4$ lattices at $β=5.1$ and ma=0.01. We provide evidence for $Z(3)$ tunnelling. We determine a critical chemical potential of $μa \simeq 0.1$ which is unexpectedly low. We also determine the dependence of the onset of the observed phase transition on

Bertrand Le Roy

We build generalizations of the Grassmann algebras from a few simple assumptions which are that they are graded, maximally symmetric and contain an ordinary Grassmann algebra as a subalgebra. These algebras are graded by Z_{n}^{3} and display surprising properties that indicate their possible application to the modelization of quark fields. We build the gene

A. S. Blaer, H. C. Ren, O. Tchernyshyov

The high-$T_c$ cuprates are possible candidates for d-wave superconductivity, with the Cooper pair wave function belonging to a non-trivial irreducible representation of the lattice point group. We argue that this d-wave symmetry is related to a special form of the fermionic kinetic energy and does not require any novel pairing mechanism. In this context, we

Bernd Siebert

We present an approach to Gromov-Witten invariants that works on arbitrary (closed) symplectic manifolds. We avoid genericity arguments and take into account singular curves in the very formulation. The method is by first endowing mapping spaces from (prestable) algebraic curves into the symplectic manifold with the structure of a Banach orbifold and then ex

C. M. Hung, E. V. Shuryak

We calculate electromagnetic production from highly excited hadronic matter created in heavy ion collisions. The rates include the usual lowest order processes in quark-gluon plasma plus the usual reactions in the hadronic phase, related with rho,a_1 mesons. The space-time integration is done using a hydrodynamical model. We have found that dilepton mass spe

P. Zavada

The paper deals with a fractional derivative introduced by means of the Fourier transform. The explicit form of the kernel of general derivative operator acting on the functions analytic on a curve in complex plane is deduced and the correspondence with some well known approaches is shown. In particular, it is shown how the uniqueness of the operation depend

T. Kojima, V. Korepin

We consider the quantum nonlinear Schrödinger equation in one space and one time dimension. We are interested in the non-free-fermionic case. We consider static temperature-dependent correlation functions. The determinant representation for correlation functions simplifies in the small mass limit of the Bose particle. In this limit we describe the correlatio

K. Asano, T. Fukuyama

The mass distribution of the lensing galaxy of the multiple quasar PG1115+080 has been studied. Using the observational data of Christian et al. (1987, ApJ 464, 92), we applied a single elliptical lens model with a softened power-law behavior. It has been revealed that the image positions, amplifications and time delays of this lensing system cannot be expla

T. H. Baker, P. J. Forrester

Multivariable generalizations of the classical Hermite, Laguerre and Jacobi polynomials occur as the polynomial part of the eigenfunctions of certain Schrödinger operators for Calogero-Sutherland-type quantum systems. For the generalized Hermite and Laguerre polynomials the multidimensional analogues of many classical results regarding generating functions,

H. C. Rosu

One can find some comments related to the isospectral issue

V. P. Karassiov

Hamiltonians of a wide-spread class of $G_{inv}$-invariant nonlinear quantum models, including multiboson and frequency conversion ones, are expressed as non-linear functions of $sl(2)$ generators. It enables us to use standard variational schemes, based on $sl(2)$ generalized coherent states as trial functions, for solving both spectral and evolution tasks.

Soo-Young Lee, Jae-Rok Kahng, Sahng-Kyoon Yoo, D. K. Park

By using a usual instanton method we obtain the energy splitting due to quantum tunneling through the triple well barrier. It is shown that the term related to the midpoint of the energy splitting in propagator is quite different from that of double well case, in that it is proportional to the algebraic average of the frequencies of the left and central well

S. Ćwiok, J. Dobaczewski, P. -H. Heenen, P. Magierski

Ground state properties of the superheavy elements (SHE) with Z from 108 to 128 and N from 150 to 192 are investigated using both the Skyrme-Hartree-Fock method with a density-independent contact pairing interaction and the macroscopic-microscopic approach with an average Woods-Saxon potential and a monopole pairing interaction. Detailed analysis of binding

W. Satuła, J. Dobaczewski, J. Dudek, W. Nazarewicz

Quadrupole and hexadecapole moments of superdeformed bands in the $A$$\sim$150 mass region have been analyzed in the cranking Skyrme-Hartree-Fock model. It is demonstrated that, independently of the intrinsic configuration and of the proton and neutron numbers, the charge moments calculated with respect to the doubly-magic superdeformed core of $^{152}$Dy ca

L. Wilets, S. Hartmann, P. Tang

The chromo-dielectric soliton model (CDM) is Lorentz- and chirally-invariant. It has been demonstrated to exhibit dynamical chiral symmetry breaking and spatial confinement in the locally uniform approximation. We here study the full nonlocal quark self energy in a color-dielectric medium modeled by a two parameter Fermi function. Here color confinement is m

Y. Nara, A. Ohnishi, T. Harada, A. Engel

In a framework of intranuclear cascade (INC) type calculation, we study a momentum spectrum in reactions \KK at a beam momentum of 1.65 GeV/c. INC model calculations are compared with the relativistic impulse approximation (RIA) calculations to perform the detailed study of the reaction mechanism. We find that the INC model can reproduce the experimental dat

Jan de Boer, Kostas Skenderis

We derive the low energy effective action of the heterotic superstring in superspace. This is achieved by coupling the covariantly quantized Green-Schwarz superstring of Berkovits to a curved background and requiring that the sigma model has superconformal invariance at tree level and at one loop in $\a&#39;$. Tree level superconformal invariance yields the

P. Ramond

$N=1$ supersymmetric gauge theories with global flavor symmetries contain a gauge invariant W-superalgebra which acts on its moduli space of gauge invariants. With adjoint matter, this superalgebra reduces to a graded Lie algebra. When the gauge group is $SO(n_c)$, with vector matter, it is a W-algebra, and the primary invariants form one of its representati

Giampiero Esposito

When quantum supergravity is studied on manifolds with boundary, one may consider local boundary conditions which fix on the initial surface the whole primed part of tangential components of gravitino perturbations, and fix on the final surface the whole unprimed part of tangential components of gravitino perturbations. This paper studies such local boundary

W. A. Sabra, S. Thomas, N. Vanegas

The holomorphic homogeneous prepotential encoding the special geometry of the special Kähler manifolds ${\textstyle SU(1,n)\over \textstyle U(1)\otimes SU(n)}$ is constructed using the symplectic embedding of the isometry group $SU(1,n)$ into $Sp(2n+2,{\hbox{\bf R}})$. Also the automorphic functions of these manifolds are discussed.

O. Coceal, W. A. Sabra, S. Thomas

Recently Olesen has shown the existence of dual string solutions to the equations of ideal Magnetohydrodynamics that describe the long wavelength properties of electrically charged plasmas. Here, we extend these solutions to include the case of plasmas consisting of point like dyons, which carry both electric and magnetic charge. Such strings are dyonic in t

D. V. Antonov, D. Ebert

The nonabelian Stokes theorem, representing a Wilson loop as an integral over all the orientations in colour space, and the cumulant expansion are used for derivation of the string effective action in SU(2) gluodynamics. The obtained theory is the theory of the rigid string interacting with the rank two antisymmetric Kalb-Ramond fields. In this model there e

M. Bordag, K. Kirsten, E. Elizalde, S. Leseduarte

The Casimir energy corresponding to a massive scalar field with Dirichlet boundary conditions on a spherical bag is obtained. The field is considered, separately, inside and outside the bag. The renormalization procedure that is necessary to apply in each situation is studied in detail, in particular the differences occurring with respect to the case when th

M. Bordag, K. Kirsten

The vacuum energy of a scalar field in a spherically symmetric background field is considered. It is expressed through the Jost function of the corresponding scattering problem. The renormalization is discussed in detail and performed using the uniform asymptotic expansion of the Jost function. The method is demonstrated in a simple explicit example.

Richard J. Szabo

We review equivariant localization techniques for the evaluation of Feynman path integrals. We develop systematic geometric methods for studying the semi-classical properties of phase space path integrals for dynamical systems, emphasizing the relations with integrable and topological quantum field theories. Beginning with a detailed review of the relevant m

Martin Markl

S. Axelrod and I.M. Singer constructed a compactification of the configuration space of distinct points in a Riemannian manifold V. A similar compactification for the moduli space of configurations of distinct points in the plane (mod the affine group action) was considered by E. Getzler and J.D.S. Jones. They observed that this compactification carries a na

Fiorenzo Bastianelli, Luca Consoli

We construct a locally supersymmetric action for the scalar particle, and study its relation with the usual reparametrization invariant action. The mechanisms at work are similar to those employed in the embedding of the bosonic string into the fermionic one, originally due to Berkovits and Vafa in their search for a universal string. The simpler algebraic s

V. E. Korepin, T. Oota

We consider the classical self-dual Yang-Mills equation in 3+1-dimensional Minkowski space. We have found an exact solution, which describes scattering of $n$ plane waves. In order to write the solution in a compact form, it is convenient to introduce a scattering operator $\hat{T}$. It acts in the direct product of three linear spaces: 1) universal envelopi

Andrei Afanasev

Virtual Compton Scattering (VCS) at low transferred momenta to the proton ($t$) and sufficiently high c.m. energies ($s$) may be used to a) study $Q^2$--dependence of leading $t$--channel exchanges and b) look for onset of scaling behavior with increasing $Q^2$. I discuss the implications for perturbative and nonperturbative QCD and suggest possible experime

A. L. Ayala, M. B. Gay Ducati, E. M. Levin

In this talk we present our detail study ( theory and numbers) [1] on the shadowing corrections to the gluon structure functions for nuclei. Starting from rather contraversial information on the nucleon structure function which is originated by the recent HERA data, we develop the Glauber approach for the gluon density in a nucleus based on Mueller formula [

J. Wudka

A model independent study of non-Standard Model CP-violating processes is presented with emphasis on the observability of the effects.

Kacper Zalewski

Two complementary approaches to the theory of heavy quarkonia are discussed. The nonrelativistic potential models give amazingly accurate predictions, but lack a theoretical justification. The expansion in powers of $v/c$ is theoretically very acceptable, but is not as good in giving numerical predictions. The importance of combining these two approaches is

Berthold Stech

An explicit model is presented which gives the momentum transfer-dependent ratios of form factors of hadronic currents. For the unknown Isgur-Wise function and its generalization for transitions to light particles a simple phenomenological Ansatz is added. The model allows a calculation of all form factors in terms of mass parameters only. It is tested by co

E. Mendel, G. Nolte

We have been able to observe directly extended instantons on the lattice, with a new method that does not require dislocations to measure them, and where we do not perform cooling. We showed, based on the simple Abelian Higgs model in $1+1$ dim., that one can extract the instanton and anti-instanton density and their size, by measuring the topological charge

Terrence Draper, Constantine Nenkov, Mike Peardon

We report results of autocorrelation measurements in pure $SU(3)$ lattice gauge theory. The computations are performed on the {\sc convex spp1200} parallel platform within the {\sc canopy} programming environment. The focus of our analysis is on typical autocorrelation times and optimization of the mixing ratio between overrelaxation and pseudo-heatbath swee

Junko Shigemitsu

Recent results in Quarkonia are reviewed, including updates on spectroscopy and $α_s$, and a first look at quarkonium annihilation decays.

T. DeGrand, A. Hasenfratz, P. Hasenfratz, P. Kunszt

We report our progress constructing a fixed-point action for fermions interacting with SU(3) gauge fields.

W. Beirl, A. Hauke, P. Homolka, H. Markum

We compare different models of a quantum theory of four-dimensional lattice gravity based on Regge&#39;s original proposal. From Monte Carlo simulations we calculate two-point functions between geometrical quantities and estimate the masses of the corresponding interaction particles.

Grigorios I. Poulis

Abelian dominance in the case of color sources in the fundamental representation is shown to follow from certain properties of maximal abelian projected SU(2) gauge theory. The possibility of having an analog of abelian dominance in the case of adjoint representation sources is addressed in the same framework.