July 1999 arXiv papers — page 3

The OPAL collaboration, G. Abbiendi et al

A sample of Z decays containing b-flavoured hadrons is tagged using leptons, and events having precise proper time measurements are selected. These events are used to study Bs oscillations. using the lepton to tag the decay b-flavour and jet charge or a second lepton, where available, to determine the produced b-flavour. The flavour (b or b-bar) at decay is

The OPAL collaboration, G. Abbiendi et al

A search is described for the generic process e+e- to X Y, where X is a neutral heavy scalar boson decaying into a pair of photons, and Y is a neutral heavy boson (scalar or vector) decaying into a fermion pair. The search is motivated mainly by the cases where either X, or both X and Y, are Higgs bosons. In particular, we investigate the case where X is the

D0 Collaboration, B. Abbott

We measure the subjet multiplicity M in jets reconstructed with a successive combination type of jet algorithm (k_T). We select jets with 55<E_T<100 GeV and | η| < 0.5. We compare similar samples of jets at sqrt{s} = 1800 and 630 GeV. The HERWIG Monte Carlo simulation predicts that 59% of the jets are gluon jets at \sqrt{s} = 1800, and 33% at sqrt{s} = 630.

V. Burdyuzha, O. Lalakulich, G. Vereshkov, Yu. Ponomarev

The problem of the physical nature and the cosmological genesis of Lambda-term is discussed. This problem can&#39;t be solved in terms of the current quantum field theory which operates with Higgs and non-perturbative vacuum condensates and takes into account the changes of these condensates during relativistic phase transitions. The problem can&#39;t be com

Banibrata Mukhopadhyay, Sandip K. Chakrabarti

Separation of the Dirac equation in the spacetime around a Kerr black hole into radial and angular coordinates was done by Chandrasekhar in 1976. In the present paper, we solve the radial equations in a Schwarzschild geometry semi-analytically using Wentzel-Kramers-Brillouin approximation (in short WKB) method. Among other things, we present analytical expre

Zhong Chao Wu

The constrained instanton method is used to study quantum creation of a $BTZ$ black hole. It is found that the relative creation probability is the exponential of the negative sum of the entropy associated with the outer and inner black hole horizons. The quantum creations of the 4- or higher dimensional versions of the $BTZ$ black hole are also studied.

P. Orellana, F. Claro

We show that, under the passage of an electromagnetic terahertz pulse, an asymmetric double barrier device may act as an on/off current switch, depending on the bias. The time-dependent response of the device is discussed.

David A. Kessler

We present the analytic solution of the Mode III steady-state crack in a square lattice with piecewise linear springs and Kelvin viscosity. We show how the results simplify in the limit of large width. We relate our results to a model where the continuum limit is taken only along the crack direction. We present results for small velocity, and for large visco

D. A. Gorokhov, G. Blatter

An elastic string embedded in 3D space and subject to a short-range correlated random potential exhibits marginal pinning at high temperatures, with the pinning length $L_c(T)$ becoming exponentially sensitive to temperature. Using a functional renormalization group (FRG) approach we find $L_c(T) \propto \exp[(32/π)(T/T_{\rm dp})^3]$, with $T_{\rm dp}$ the d

D. A. Gorokhov, G. Blatter

We discuss the main features of Hall tunneling of pancake vortices in superclean high-$T_{c}$ superconductors. The general formalism for the calculation of the lifetime of a vortex pinned in a metastable configuration is described. The results are applied to the problem of quantum tunneling of a pancake vortex from a columnar defect in the limit of a small d

M. Kataoka, C. J. B. Ford, G. Faini, D. Mailly

We have detected oscillations of the charge around a potential hill (antidot) in a two-dimensional electron gas as a function of a perpendicular magnetic field B. The field confines electrons around the antidot in closed orbits, the areas of which are quantised through the Aharonov-Bohm effect. Increasing B reduces each state&#39;s area, pushing electrons cl

M. Kataoka, C. J. B. Ford, G. Faini, D. Mailly

We have detected oscillations of the charge around a potential hill (antidot) in a two-dimensional electron gas as a function of a large magnetic field B. The field confines electrons around the antidot in closed orbits, the areas of which are quantised through the Aharonov-Bohm effect. Increasing B reduces each state&#39;s area, pushing electrons closer to

M. Campellone, F. Ritort

We investigate the critical behavior of a three-dimensional short-range spin glass model in the presence of an external field $\eps$ conjugated to the Edwards-Anderson order parameter. In the mean-field approximation this model is described by the Adam-Gibbs-DiMarzio approach for the glass transition. By Monte Carlo numerical simulations we find indications

Mauro Bologna, Paolo Grigolini, Juri Riccardi

The Levy diffusion processes are a form of non ordinary statistical mechanics resting, however, on the conventional Markov property. As a consequence of this, their dynamic derivation is possible provided that (i) a source of randomness is present in the corresponding microscopic dynamics and (ii) that the consequent process of memory erasure is properly tak

Paolo Grigolini, Marco G. Pala, Luigi Palatella, Roberto Roncaglia

We study the entropy time evolution of a quantum mechanical model, which is frequently used as a prototype for Anderson&#39;s localization. Recently Latora and Baranger [V. Latora, M. Baranger, Phys. Rev.Lett. 82, 520(1999)] found that there exist three entropy regimes, a transient regime of passage from dynamics to thermodynamics, a linear in time regime of

A. E. Koshelev, L. N. Bulaevskii

The Josephson plasma resonance (JPR) provides a sensitive probe of vortex states in layered superconductors. We demonstrate that in the case of weak damping in the liquid phase, broadening of the JPR line is caused mainly by random Josephson coupling arising from the density fluctuations of pancake vortices. In this case the JPR line has the universal shape,

Nikolai M. Chtchelkatchev, Gordey B. Lesovik, Gianni Blatter

We determine the quasi-particle excitation spectrum in the normal region of a narrow ballistic superconductor--normal-metal--superconductor (SNS) Josephson contact. Increasing the effective chemical potential in the contact converts the electronic levels into Andreev-levels carrying supercurrent. The opening of these superchannels leads to a supercurrent qua

Alexander Altland, C. H. W. Barnes, F. W. J. Hekking, A. J. Schofield

A novel method for detecting Luttinger-liquid behavior is proposed. The idea is to measure the tunneling conductance between a quantum wire and a parallel two-dimensional electron system as a function of both the potential difference between them, $V$, and an in-plane magnetic field, $B$. We show that the two-parameter dependence on $B$ and $V$ allows for a

Leone Fronzoni, Paolo Grigolini, Simone Montangero

We focus our attention on dynamical processes characterized by an entropic index Q<1. According to the probabilistic arguments of Tsallis and Bukman [C.Tsallis, D.J. Bukman, Phys. Rev. E 54,R2197 (1996)] these processes are subdiffusional in nature. The non-extensive generalization of the Kolmogorov-Sinai entropy yielding the same entropic index implies the

A. I. Olemskoi, A. V. Khomenko, V. P. Koverda

The explosive crystallization of germanium ultradisperse amorphous films is studied experimentally. We show that crystallization may be initiated by local heating at the small film thickness but it realizes spontaneously at the large ones. The fractal pattern of the crystallized phase is discovered that is inherent in the phenomena of diffusion limited aggre

Philippe Jund, Remi Jullien

The multidimensional topography of the collective potential energy function of a so-called strong glass former (silica) is analyzed by means of classical molecular dynamics calculations. Features qualitatively similar to those of fragile glasses are recovered at high temperatures : in particular an intrinsic characteristic temperature $T_c\simeq 3500$K is ev

Minchul Lee, Mahn-Soo Choi, M. Y. Choi

We investigate the quantum phase transitions in two capacitively coupled two-dimensional Josephson-junction arrays with charge frustration. The system is mapped onto the S=1 and $S=1/2$ anisotropic Heisenberg antiferromagnets near the particle-hole symmetry line and near the maximal-frustration line, respectively, which are in turn argued to be effectively d

L. Dobrek, M. Gajda, M. Lewenstein, K. Sengstock

We demonstrate numerically the efficient generation of vortices in Bose-Einstein condensates (BEC) by using a ``phase imprinting&#39;&#39; method. The method consist of passing a far off resonant laser pulse through an absorption plate with azimuthally dependent absorption coefficient, imaging the laser beam onto a BEC, and thus creating the corresponding no

Niels Asger Mortensen, Antti-Pekka Jauho, Karsten Flensberg, Henning Schomerus

We present numerical calculations of the conductance of an interface between a phase-coherent two-dimensional electron gas and a superconductor with a quantum point contact in the normal region. Using a scattering matrix approach we reconsider the geometry of De Raedt, Michielsen, and Klapwijk [Phys. Rev. B, 50, 631 (1994)] which was studied within the time-

Philip Boyland, Mark Stremler, Hassan Aref

Topological techniques are used to study the motions of systems of point vortices in the infinite plane, in singly-periodic arrays, and in doubly-periodic lattices. The reduction of each system using its symmetries is described in detail. Restricting to three vortices with zero net circulation, each reduced system is described by a one degree of freedom Hami

ANTARES Collaboration

The ANTARES Collaboration proposes to construct a large area water Cherenkov detector in the deep Mediterranean Sea, optimised for the detection of muons from high-energy astrophysical neutrinos. This paper presents the scientific motivation for building such a device, along with a review of the technical issues involved in its design and construction. The o

Limin Wang, Marc Kamionkowski

We derive an expression for the non-Gaussian cosmic-microwave-background (CMB) statistic $I_l^3$ defined recently by Ferreira, Magueijo, and Górski in terms of the slow-roll-inflation parameters $ε$ and $η$. This result shows that a nonzero value of $I_l^3$ in COBE would rule out single-field slow-roll inflation. A sharp change in the slope of the inflaton p

B. P. Holden, R. C. Nichol, A. K. Romer, A. Metevier

We have conducted a redshift survey of sixteen cluster candidates from the Palomar Distant Cluster Survey (PDCS) to determine both the density of PDCS clusters and the accuracy of the estimated redshifts presented in the PDCS catalog (Postman et. al. 1996). We find that the matched-filter redshift estimate presented in the PDCS has an error sigma_z = 0.06 in

J. Christopher Howk, Kenneth R. Sembach

Recent high-resolution observations of metal absorption lines in high-redshift damped Ly-alpha systems have shown that Al III, a tracer of moderately-ionized gas, very often has a velocity structure indistinguishable from that of low-ionization gas. Regions of ionized and neutral hydrogen in these systems are likely cospatial. The higher-ionization Si IV and

Curtis Struck, Daniel C. Smith

We propose that turbulent heating, wave pressure and gas exchanges between different regions of disks play a dominant role in determining the preferred, quasi-equilibrium, self-similar states of gas disks on large-scales. We present simple families of analytic, thermohydrodynamic models for these global states, which include terms for turbulent pressure and

Linqing Wen, Ronald A. Remillard, Hale V. Bradt

X 1908+075 is an optically unidentified and highly absorbed X-ray source that appears in early surveys such as Uhuru, OSO-7, Ariel V, HEAO-1, and the EXOSAT Galactic Plane Survey. These surveys measured a source intensity in the range of 2-12 mCrab at 2-10 keV, and the position was localized to ~ 0.5 degrees. We use the Rossi X-ray Timing Explorer (RXTE) All

Lewis Jones, Ian Smail, Warrick J. Couch

We combine morphological classifications from deep HST imaging of a sample of 3 clusters at z=0.31 and a further 9 clusters at z=0.37-0.56 with existing spectroscopic observations of their E and S0 populations, to study the relative spectral properties of these two galaxy types. We have also used similar data for the Coma cluster as a present day bench-mark

S. Esposito, G. Mangano, G. Miele, O. Pisanti

We report on the results of a recent evaluation of all percent level corrections to weak rates of processes converting n <-> p, which are crucial for the determination of the 4He mass fraction produced during primordial nucleosynthesis.

S. Esposito, G. Mangano, G. Miele, O. Pisanti

We report the results of a new accurate evaluation of light nuclei yields in primordial nucleosynthesis. The relic densities of 4He, D and 7Li have been numerically obtained via a new updated version of the standard BBN code.

S. Esposito, G. Mangano, G. Miele, O. Pisanti

A new accurate evaluation of primordial light nuclei abundances is presented. The proton to neutron conversion rates have been corrected to take into account radiative effects, finite nucleon mass, thermal and plasma corrections. The theoretical uncertainty on 4He is so reduced to the order of 0.1%.

R. Plaga, O. C. de Jager, A. Dar

We propose a new hypothesis for the origin of non-solar hadronic cosmic rays (CRs) at all energies: Highly relativistic, narrowly collimated jets from the birth or collapse of neutron stars (NSs) in our Galaxy accelerate ambient disk and halo matter to CR energies and disperse it in ``hot spots&#39;&#39; which they form when they stop in the Galactic halo. S

Katherine Blundell, Steve Rawlings, Chris Willott

We describe the inter-dependence of four properties of classical double radio sources - spectral index, linear size, luminosity and redshift - from an extensive study based on spectroscopically-identified complete samples. We use these relationships to discuss aspects of strategies for searching for radio galaxies at extreme redshifts, in the context of poss

Thorsten Naab, Andreas Burkert

We study a possible formation mechanism for elliptical/S0 galaxies using N-body simulations with GRAPE. A close galaxy encounter which does not lead to a merger can induce a strong bar in an initially axisymmetric disk. This bar is unstable against bending oscillations and loses angular momentum to the dark halo. After 6 Gyrs the remnant is spheroidal with a

A. Treves, Y. H. Zhang, F. Tavecchio, A. Celotti

We present a detailed Cross Correlation analysis of the light curves of the X-ray bright BL Lac object Mkn 421 observed with $Beppo$SAX period 1997-1998. Monte Carlo simulations are performed in order to estimate the uncertainties. We found that in one occasion the lag is negative.

Elena Nikogossyan, Florence Durret, Daniel Gerbal, Frederic Magnard

(Abridged) We present a morphological and structural analysis of the Richness zero cluster ABCG 194, known as a ``linear cluster&#39;&#39;, based on a catalogue of 97 galaxies with B magnitudes and redshifts, a ROSAT PSPC image and radio data. The overall large scale structure is rather smooth and comparable at optical and X-ray wavelengths. The cluster is e

W. A. Dziembowski, S. Cassisi

We present a survey of nonradial mode properties in evolutionary sequences of RR Lyrae star models. Attention is focused on the modes that may be driven by the opacity mechanism and on those that may be excited as a consequence of the 1:1 resonance with the radial pulsation. Qualitatively, all the models share the same properties of the nonradial modes. At t

Anja C. Andersen, Rita Loidl, Susanne Hofner

For amorphous carbon several laboratory extinction data are available, which show quite a wide range of differences due to the structural complexity of this material. We have calculated self-consistent dynamic models of circumstellar dust-shells around carbon-rich asymptotic giant branch stars, based on a number of these data sets. The structure and the wind

R. M. Campbell

We describe a method for removing ionospheric effects from single-frequency radio data a posteriori. This method is based on a theoretical climatological model developed by the USAF, which returns electron density as a function of position and time along the line of sight to the source. Together with a model of the earth&#39;s magnetic field, ionospheric del

Ben Moore, Sebastiano Ghigna, Fabio Governato, George Lake

We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that closely matches observations. However, the survival of dark matter substructure also occurs on galactic scales, leading to

J. E. Larkin, A. Quirrenbach, J. R. Graham

We are proposing to build a new integral field instrument (OSIRIS) for use with the Keck Adaptive Optics System. It will utilize a large (1024 element) fiber optic bundle to slice the field and feed a standard infrared spectrograph with a spectral resolution of 5000. To improve the fill factor of the fiber bundle, we plan on coupling it to a matched lenslet

R. A. Johnson, S. F. Beaulieu, R. A. W. Elson, G. Gilmore

The rich star clusters in the Large Magellanic Cloud (LMC) are ideal for studying the process of star formation. Here we focus on the determination of age spreads amongst the massive stars in two young clusters, NGC1818 and NGC1805. We present colour magnitude diagrams (derived from HST data) for these clusters, and discuss the difficulties in age spread det

A. K Romer, R. C. Nichol, B. P. Holden, M. P. Ulmer

We present the Bright SHARC (Serendipitous High-Redshift Archival ROSAT Cluster) Survey, which is an objective search for serendipitously detected extended X-ray sources in 460 deep ROSAT PSPC pointings. The Bright SHARC Survey covers an area of 178.6 sq.deg and has yielded 374 extended sources. We discuss the X-ray data reduction, the candidate selection an

Christopher J. Conselice, Matthew A. Bershady, Anna Jangren

We present a detailed study of rotational asymmetry in galaxies for both morphological and physical diagnostic purposes. An unambiguous method for computing asymmetry is developed, robust for both distant and nearby galaxies. By degrading real galaxy images, we test the reliability of this asymmetry measure over a range of observational conditions, e.g. spat

Yun Wang

Because of flux conservation, flux-averaging {\it justifies} the use of the distance-redshift relation for a smooth universe in the analysis of type Ia supernova (SN Ia) data. We have combined the SN Ia data from the High-$z$ SN Search and the Supernova Cosmology Project, and binned the combined data by flux-averaging in redshift intervals of $Δz=0.05$ and $

Stephan Dürr, Joachim Kambor

We calculate the correlator between two external vector-currents having the quantum-numbers of a charged kaon. We give the renormalized expression to two loops in standard chiral perturbation theory in the isospin limit, which, as a physical result, is finite and scale-independent. Applications include a low energy theorem, valid at two loop order, of a flav

A. Sadori, M. Grilli

We investigate the formation of charge domain walls in an electron-doped extended Hubbard model for the superconducting cuprates. Within an unrestricted Hartree-Fock approach, extended by the introduction of slave-bosons to obtain a more proper treatment of strong correlations, we demonstrate the occurrence of stripes in the (1,1) and (1,-1) directions havin

Martin Howard, Per Frojdh, Kent Baekgaard Lauritsen

We study the surface critical behavior of branching-annihilating random walks with an even number of offspring (BARW) and directed percolation (DP) using a variety of theoretical techniques. Above the upper critical dimensions d_c, with d_c=4 (DP) and d_c=2 (BARW), we use mean field theory to analyze the surface phase diagrams using the standard classificati

Edward R. Floyd

The trajectory representation in the classical limit (\hbar \to 0) manifests a residual indeterminacy. We show that the trajectory representation in the classical limit goes to neither classical mechanics (Planck's correspondence principle) nor statistical mechanics. This residual indeterminacy is contrasted to Heisenberg uncertainty. We discuss the relation

Dima L. Shepelyansky, Pil Hun Song

We study the effect of electron-electron interaction on a two dimensional (2D) disordered lattice. For the case of two electrons the analytical estimates are presented showing a transition from localized to delocalized states in a way similar to the Anderson transition in 3D. The localized phase corresponds to large values of the parameter r_s, which is dete

V. E. Rochev

A new approach to nonperturbative calculations in quantum electrodynamics is proposed. The approach is based on a regular iteration scheme for solution of Schwinger-Dyson equations for generating functional of Green functions. The approach allows one to take into account the gauge invariance conditions (Ward identities) and to perform the renormalization pro

Mohsen Alishahiha, Yaron Oz

We consider N=2 superconformal theories defined on a 3+1 dimensional hyperplane intersection of two sets of M5 branes. These theories have (tensionless) BPS string solitons. We use a dual supergravity formulation to deduce some of their properties via the AdS/CFT correspondence.

Shahar Hod

An astrophysically realistic model of wave dynamics in black-hole spacetimes must involve a non-spherical background geometry with angular momentum. We consider the evolution of gravitational (and electromagnetic) perturbations in rotating Kerr spacetimes. We show that a rotating Kerr black hole becomes `bald&#39; slower than the corresponding spherically-sy

R. de Ritis, A. A. Marino, C. Rubano, P. Scudellaro

We join quintessence cosmological scenarios with the duality simmetry existing in string dilaton cosmologies. Actually, we consider the tracker potential type $V = V_0/ϕ^α$ and show that duality is only established if $α= - 2$.

Kiyomi Okamoto, Takashi Tonegawa, Yutaka Takahashi, Makoto Kaburagi

We study the ground state of the model Hamiltonian of the trimerized $S=1/2$ quantum Heisenberg chain $\rm Cu_3 Cl_6 (H_2 O)_2 \cdot 2H_8 C_4 SO_2$ in which the non-magnetic ground state is observed recently. This model consists of stacked trimers and has three kinds of coupling constants between spins; the intra-trimer coupling constant $J_1$ and the inter-

Enrique Alvarez, Cesar Gomez

The infinite tension limit of string amplitudes is examined with some care, identifying the part responsible of diamagnetic behaviour as well as a peculiar paramagnetic {\em tachyon magnifying} responsible of asymptotic freedom. The way string theory represents abelian gauge theories is connected with the non-planar reggeon/pomeron amplitude and a nontrivial

Guido Altarelli, Ferruccio Feruglio, Isabella Masina

We discuss the special class of models where nearly maximal neutrino mixing is produced through the see-saw mechanism, starting from only nearly diagonal matrices for charged leptons, Dirac neutrinos and Majorana right-handed neutrinos.

S. Franz, M. A. Virasoro

We develop an interpretation of the off-equilibrium dynamical solution of mean-field glassy models in terms of quasi-equilibrium concepts. We show that the relaxation of the &#34;thermoremanent magnetization&#34; follows a generalized version of the Onsager regression postulate of induced fluctuations. We then find the rationale for the equality between the

Sawa Manoff

Transports preserving the angle between two contravariant vector fields but changing their lengths proportional to their own lengths are introduced as `conformal&#39; transports and investigated over spaces with one affine connection and metric. They are more general than the Fermi-Walker transports. In an analogous way as in the case of Fermi-Walker transpo

Tamath Rainsford

In a previous paper we derived a post-Newtonian approximation to cosmology which, in contrast to former Newtonian and post-Newtonian cosmological theories, has a well-posed initial value problem. In this paper, this new post-Newtonian theory is compared with the fully general relativistic theory, in the context of the k = 0 Friedmann Robertson Walker cosmolo

Jihn E. Kim

A pseudo-Goldstone boson for {\it quintessence} is known to require the decay constant $F_q\sim M_P$ and the height of the potential $(0.003 {\rm eV})^4$, and hence the pseudo-Goldstone boson mass of order $10^{-33}$ eV. The model-dependent axion in some superstring models is suggested as a good candidate for the quintessence. We realize this idea with a hid

Fatimah Shojai

In this paper we have solved the Bohmian equations of quantum gravity, perturbatively. Solutions up to second order are derived explicitly, but in principle the method can be used in any order. Some consequences of the solution are disscused.

M. Matsuda, Y. S. Lee, M. Greven, M. A. Kastner

A spin-glass compound, La$_{1.98}$Sr$_{0.02}$CuO$_4$, shows quasi-three-dimensional magnetic ordering below $\sim$40 K. A remarkable feature is that the magnetic correlation length along the orthorhombic $a\rm_{ortho}$ axis is much longer than that along the $b\rm_{ortho}$ axis, suggesting that the spin structure is closely related to the diagonal stripe str

Jonathan L. Rosner

A new analysis of parity violation in atomic cesium has led to the improved value of the weak charge, $Q_W({\rm Cs}) = -72.06 \pm 0.46$. The implications of this result for constraining the Peskin-Takeuchi parameters S and T and for guiding searches for new Z bosons are discussed.

Jose L. Cereceda

In this paper we provide a simple proof of the fact that for a system of two spin-1/2 particles, and for a choice of observables, there is a unique state which shows Hardy-type nonlocality. Moreover, an explicit expression for the probability that an ensemble of particle pairs prepared in such a state exhibits a Hardy-type nonlocality contradiction is given

J. P. Clemens, P. R. Rice, P. K. Rungta, R. J. Brecha

We consider the interaction of a two-level atom inside an optical parametric oscillator. In the weak driving field limit, we essentially have an atom-cavity system driven by the occasional pair of correlated photons, or weakly squeezed light. We find that we may have holes, or dips, in the spectrum of the fluorescent and transmitted light. This occurs even i

G. M. D&#39;Ariano, L. Maccone, M. F. Sacchi, A. Garuccio

We present a homodyne detection scheme to verify Bell&#39;s inequality on correlated optical beams at the output of a nondegenerate parametric amplifier. Our approach is based on tomographic measurement of the joint detection probabilities, which allows high quantum efficiency at detectors. A self-homodyne scheme is suggested to simplify the experimental set

A. Derevianko, W. R. Johnson, H. R. Sadeghpour

The photoionization cross section $σ$, spin-polarization parameters $P$ and $Q$, and the angular-distribution asymmetry parameter $β$ are calculated for the $7s$ state of francium for photon energies below 10 eV. Two distinct calculations are presented, one based on many-body perturbation theory and another based on the model potential method. Although predi

S. G. Cooper, V. I. Kukulin, R. S. Mackintosh, V. N. Pomerantsev

We present a practical $S$-matrix to potential inversion procedure for coupled-channel scattering. The inversion technique developed is applied to non-diagonal $S^J_{ll&#39;}$ for spin one projectiles, yielding a tensor interaction $T_{\rm R}$, and is also applicable to spin-1/2 plus spin-1/2 scattering. The method is a generalization of the iterative-pertur

L. Alvarez-Ruso, E. Oset, S. K. Singh, M. J. Vicente Vacas

The charge changing weak production of Delta in nucleons and nuclei is studied. The reactions e^{-} p -> Delta^{0} ν_{e} and e^{+} p -> Delta^{++} \barν_{e} are considered as a possible source of information about the weak N-Delta transition form factors. The low q^2 BNL data on neutrino production of Delta are used to extract the axial vector N-Delta coupli

Declan Persram, Charles Gale

We formulate a lattice Hamiltonian model for intermediate energy heavy ion collisions. Our approach incorporates a momentum-dependent nuclear mean field that yields an optical potential that agrees with proton-nucleus experiments and that also receives support from measurements involving heavy ions. We emphasize the precision of our numerical results in conn

R. Lichtenthaeler, A. Lepine-Szily, M. S. Hussein

The elastic scattering of 12C+24Mg has been studied by means of a phase-shift analysis of 21 angular distributions ranging from Elab=16MeV up to Elab=40MeV. A tri-dimensional plot of the reflection coefficient of the S-matrix as a function of the angular momentum and the energy shows a well defined region of energy which separates two regimes: strong absorpt

P. V. Sedyshev, P. Mohr, H. Beer, H. Oberhummer

At the Karlsruhe and Tuebingen 3.75 MV Van de Graaff accelerators the thermonuclear 50Ti(n,gamma)51Ti(5.8 min) cross section was measured by the fast cyclic activation technique via the 320.852 and 928.65 keV gamma-ray lines of the 51Ti-decay. Metallic Ti samples of natural isotopic composition and samples of TiO2 enriched in 50Ti by 67.53 % were irradiated

Yoram Last, Barry Simon

Neat stuff about eigenfunctions, transfer matrices, and a.c. spectrum of one-dimensional Schrodinger operators

Susan Howson

If G is a pro-p, p-adic, Lie group and if $Λ(G)$ denotes the Iwasawa algebra of G then we present a formula for determining the $Λ(G)$-rank of a finitely generated $Λ(G)$-module. This is given in terms of the G homology groups of the module. We explore some consequences of this for the structure of $Λ(G)$-modules.

Martin Gremm, Anton Kapustin

It has been conjectured that Little String Theories in six dimensions are holographic to critical string theory in a linear dilaton background. We test this conjecture for theories arising on the worldvolume of heterotic fivebranes. We compute the spectrum of chiral primaries in these theories and compare with results following from Type I-heterotic duality

Gerald V. Dunne

We present a simple algorithm to implement the generalized derivative expansion introduced previously by L-H. Chan, and apply it to the calculation of the one-loop mass correction to the classical soliton mass in the 1+1 dimensional Jacobi model. We then show how this derivative expansion approach implies that the total (bosonic plus fermionic) mass correcti

F. S. Roux, T. Torma, B. Holdom

We construct the effective action and gap equations for nonperturbative fermion 4-point functions. Our results apply to situations in which fermion masses can be ignored, which is the case for theories of strong flavor interactions involving standard quarks and leptons above the electroweak scale. The structure of the gap equations is different from what a n

L. Lavoura

I present a new model for the quark mass matrices, which uses four scalar doublets together with a horizontal symmetry S3 x Z3. The model is inspired on a suggestion made a few years ago by Ma, but it is different. The predictions |Vts| \approx ms/mb and |Vub/Vcb| > 0.085 are obtained. Flavour-changing neutral Yukawa interactions do not exist in the down-typ

Dubravko Klabucar, Dalibor Kekez

It is discussed how various Ans&#34;atze for the dressed quark-photon (qq gamma) vertices Gamma^mu(q,q&#39;) influence the asymptotics of the gamma^* gamma -> pi^0 transition form factor.

Fu Jinghua, Liu Lianshou

A new signal is proposed for the colour reconnection in the hadronic decay of W+ W- in e+e- collisions. Using Pythia Monte Carlo it is shown that this signal, being based on the factorial correlator, is more sensitive than the ones using only averaged quantities.

David E. Miller

After a short description of the currents coming from the known conservation laws in classical physics, we look at some further cases which arise after quantization in relation to quantum chromodynamics (QCD) at finite temperature. In these cases, however, some basic changes appear with the anomalies. First we go into the relationship between the trace of th

Gian Franco Bonini, Christof Wetterich

We investigate the time evolution of a classical ensemble of isolated periodic chains of O(N)-symmetric anharmonic oscillators. Our method is based on an exact evolution equation for the time dependence of correlation functions. We discuss its solutions in an approximation which retains all contributions in next-to-leading order in a 1/N expansion and preser

V. Burdyuzha, O. Lalakulich, Yu. Ponomarev, G. Vereshkov

If the preon structure of quarks, leptons and gauge bosons will be proved then in the Universe during relativistic phase transition the production of nonperturbative preon condensates has been occured collective excitations of which are perceived as pseudogoldstone bosons. Dark matter consisting of pseudogoldstone bosons of familon type contains a &#34;hot&#

M. M. Nojiri

In this talk, I review precision SUSY study at LHC and TeV scale e+e- linear colliders (LC). We discuss the study of the 3 body decay of the second lightest neutralino χ^0_2--> χ^0_1 ll or the 2 body decay χ^0_2-->\tilde{l}l at LHC. In the former case, the whole m_{ll} distribution observed at LHC would constrain ino mixing and slepton masses. On the other h

R. N. Lee, A. I. Milstein, V. M. Strakhovenko

The quasiclassical Green functions of the Dirac and Klein-Gordon equations in the external electric field are obtained with the first correction taken into account. The relevant potential is assumed to be localized, while its spherical symmetry is not required. Using these Green functions, the corresponding wave functions are found in the approximation simil

Zheng Xiaoping, Hou Defu, Li Jiarong

We study the effect of unlinearized medium on the collective excitations in quark-gluon plasma. We present two kinds of non-Abelian oscillation solutions which respectively correspond to weakly and strongly nonlinear coupling of field components in color space. We also show that the weakly nonlinear solution is similar to Abelian-like one but has the frequen

Zheng Xiaoping, Li Jiarong, Liu Lianggang, Guo Shuohong

We present an effective relaxation-time theory to study the collisionless quark-gluon plasma. Applying this method we calculate the damping rate to be of order $g^2T$ and find plasmon scattering is the damping mechanism. The damping for the transverse mode is stronger than the longitudinal one.

Kh. M. Beshtoev

In this work it is shown that, in contrast to the strong and electromagnetic theories, additive conserved numbers (such as lepton, aromatic and another numbers) and gamma-5 anomaly do not appear in the standard weak interaction theory. It means that in this interaction the additive numbers cannot be conserved. These results are the consequence of specific ch

C. Anastasiou, E. W. N. Glover, C. Oleari

We study massless one-loop box integrals by treating the number of space-time dimensions D as a negative integer. We consider integrals with up to three kinematic scales (s, t and either zero or one off-shell legs) and with arbitrary powers of propagators. For box integrals with q kinematic scales (where q=2 or 3) we immediately obtain a representation of th

F. Gliozzi, P. Provero

The confining string in presence of dynamical quarks can behave in different ways, depending on the quark masses and on the number N_f N_c of charge species. For light masses and large N_f N_c the creation of quark pairs produces microscopic holes in the world- sheet swept by the string; as a consequence string breaking is invisible in the Wilson loop, while

P. Hernandez, K. Jansen, L. Lellouch

We confront the finite volume and small quark mass behaviour of the scalar condensate, determined numerically in quenched lattice QCD using Neuberger fermions, with predictions of quenched chiral perturbation theory. We find that quenched chiral perturbation theory describes the numerical data well, allowing us to extract the infinite volume, chiral limit sc

L. C. Bland

Polarized proton collisions will be studied at RHIC up to a total center of mass energy of 500 GeV, starting in 2002. An overview of the RHIC-spin program, and the critical components of the PHENIX and STAR detectors for spin experiments, is presented. The premier experiment within the RHIC-spin program is the determination of the fraction of the proton&#39;

G. Brandenburg, CLEO Collaboration

We have used the CLEO II detector to study the multiplicity of charged particles in the decays of B mesons produced at the $Υ(4S)$ resonance. Using a sample of 1.5 x 10^6 B meson pairs, we find the mean inclusive charged particle multiplicity to be 10.71 +- 0.02 +0.21/-0.15 for the decay of the pair. This corresponds to a mean multiplicity of 5.36 +- 0.01 +0

T. Bergfeld, CLEO Collaboration

Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II detector we have studied tau radiative decays tau --> mu nu nu gamma and tau --> e nu nu gamma. For a 10 MeV minimum photon energy in the tau rest frame, the branching fraction of a tau radiatively decaying to a muon is measured to be (3.61+-0.16+-0.35)*10^{-3}, and to an electron is (

The WA102 Collaboration, D. Barberis et al

A coupled channel analysis of the centrally produced K+K- and pi+pi- final states has been performed in pp collisions at an incident beam momentum of 450 GeV/c. The pole positions and branching ratios to pipi and KK of the f0(980), f0(1370), f0(1500) and f0(1710) have been determined. A systematic study of the production properties of all the resonances obse