October 1997 arXiv papers — page 3

A. V. Balatsky

It is shown that the patches of complex d_{xy} component are generated around magnetic impurity in the presence of the coupling between orbital moment of the condensate and impurity spin S. Locally induced d_{xy} gap leads to the fully gapped quasiparticle spectrum near impurity. The phase of the induced i d_{xy} component is determined by impurity spin and

Uwe Müssel

Competing pinning effects on a D-dimensional interface by weak impurity disorder and a periodic potential of the underlying crystal lattice are analyzed for $2<D<4$. We use both the Gaussian variational method (GVM) and the functional renormalization group $ε=4-D$ expansion (FRG) which yield different phase diagrams: Whereas the FRG always predicts a rough p

Andreas Bille, Kurt Scharnberg

The electromagnetic response of the CuO2-planes is calculated within a strong coupling theory using model tight binding bands and momentum dependent pairing interactions representing spin fluctuations and phonon exchange. The superconducting state resulting from these interactions has d-wave symmetry. With phonon exchange included the order parameter amplitu

S. Schmidt, W. Palme, B. Lüthi, M. Weiden

We present results from magnetic resonance measurements for 75-350 GHz in $α$&#39;-NaV$_{2}$O$_{5}$. The temperature dependence of the integrated intensity indicates that we observe transitions in the excited state. A quantitative description gives resonances in the triplet state at high symmetry points of the excitation spectrum of this Spin-Peierls compoun

J. De Coninck, G. Oshanin, M. Moreau

We study dynamics of a probe molecule, driven by an external constant force in a liquid monolayer on top of solid surface. In terms of a microscopic, mean-field-type approach, we calculate the terminal velocity of the probe molecule. This allows us to establish the analog of the Stokes formula, in which the friction coefficient is interpreted in terms of the

Stuart S. C. Burnett

We present three-loop formulas for the additive renormalization constant A(u,epsilon) and associated renormalization group function B(u) for the specific heat of the O(n) symmetric phi^4 model. Using this result, we obtain also the amplitude function above Tc within the minimally renormalied theory at fixed d=3. At the fixed point, the three-loop correction

Satoshi Fujimoto, Norio Kawakami

The Drude weight for the one-dimensional Hubbard model is investigated at finite temperatures by using the Bethe ansatz solution. Evaluating finite-size corrections to the thermodynamic Bethe ansatz equations, we obtain the formula for the Drude weight as the response of the system to an external gauge potential. We perform low-temperature expansions of the

V. I. Yukalov

Spin relaxation in a microscopic model of spin maser is studied theoretically. Seven qualitatively different regimes are found: free induction, collective induction, free relaxation, collective relaxation, weak superradiance, pure superradiance, and triggered superradiance. The initiation of relaxation can be originated either by an imposed initial coherence

J. Dukelsky, M. A. Martin-Delgado, T. Nishino, G. Sierra

We present a rotationally invariant matrix product method (MPM) of isotropic spin chains. This allows us to deal with a larger number of variational MPM parameters than those considered earlier by other authors. We also show the relation between the MPM and the DMRG method of White. In our approach the eigenstates of the density matrix associated with the MP

J. Shiraishi, Y. Avishai, M. Kohmoto

Stationary solutions of the Chern-Simons effective field theory for the fractional quantum Hall systems with edges are presented for Hall bar, disk and annulus. In the infinitely long Hall bar geometry (non compact case), the charge density is shown to be monotonic inside the sample. In sharp contrast, spatial oscillatory modes of charge density are found fo

Matteo Beccaria, Giulio Soliani

Nonlinear systems of the reaction-diffusion type, including Gierer-Meinhardt models of autocatalysis, are studied by using Lie algebras coming from the prolongation structure. The consequences of this analytical approach, as the determination of special exact solutions, are compared with the corresponding results obtained via numerical simulations.

M. Jonson, I. V. Krive, P. Sandström, R. I. Shekhter

We analyze recent measurements of the room temperature current-voltage characteristics of gold nanowires, whose zero current conductance is quantized in units of $2e^2/h$. A faster than linear increase of current with voltage was observed at low voltages beginning from $V_c=0.1$V. We analyze the nonlinear behavior in terms of a dynamic Coulomb blockade of co

Ulrich H. E. Hansmann, Yuko Okamoto

We present a novel Monte Carlo algorithm which enhances equilibrization of low-temperature simulations and allows sampling of configurations over a large range of energies. The method is based on a non-Boltzmann probability weight factor and is another version of the so-called generalized-ensemble techniques. The effectiveness of the new approach is demonstr

C. Nayak, Matthew P. A. Fisher, A. W. W. Ludwig, H. -H. Lin

We analyze a model of resonant point-contact tunneling between multiple Luttinger liquid leads. The model is a variant of the multi-channel Kondo model and can be related to the quantum Brownian motion of a particle on lattices with $π$-flux through each plaquette (in the 3-lead case, it is a honeycomb lattice with $π$-flux). By comparing the perturbative an

Craig Pryor

The electronic structure of pyramidal shaped InAs/GaAs quantum dots is calculated using an eight-band strain dependent $\bf k\cdot p$ Hamiltonian. The influence of strain on band energies and the conduction-band effective mass are examined. Single particle bound-state energies and exciton binding energies are computed as functions of island size. The eight-b

L. Biferale, D. Pierotti, A. Vulpiani

Dynamical Ensemble Equivalence between hydrodynamic dissipative equations and suitable time-reversible dynamical systems has been investigated in a class of dynamical systems for turbulence. The reversible dynamics is obtained from the original dissipative equations by imposing a global constraint. We find that, by increasing the input energy, the system cha

Santanu Pal, Debabrata Biswas

We derive a semiclassical trace formula for a symmetry reduced part of the spectrum in axially symmetric systems. The classical orbits that contribute are closed in (ρ,z,p_ρ,p_z) and have p_ϕ= m\hbar where m is the azimuthal quantum number. For m > 0, these orbits vary with energy and almost never lie on periodic trajectories in the full phase space in contr

Kirk Korista, Gary Ferland

We explore the effective UV-optical albedos of a variety of types of broad emission line clouds, as well as their possible effects on the observed spectra of AGN. An important albedo source in moderately ionized ionization-bounded clouds is that due to neutral hydrogen: Rayleigh scattering of continuum photons off the extreme damping wings of Lya. The photon

Michael Loewenstein, Richard Mushotzky

We review estimates of the metallicities in elliptical galaxies, with an emphasis on recent results from the ASCA satellite. X-ray spectra of elliptical galaxies are adequately fit by models consisting of hot gas with subsolar Fe abundance and roughly solar Si-to-Fe ratio, plus a hard component from an ensemble of X-ray binaries. Although complications in th

S. Mereghetti, G. L. Israel, L. Stella

We report on two RossiXTE observations of the anomalous X-ray pulsars 1E 1048.1-5937 and 1E 2259+586. Both sources have continued their almost constant spin-down during 1995/96. We carried out a search for orbital Doppler shifts, in their observed spin frequencies, deriving stringent limits on the projected semi-axis. Unless these systems have unlikely small

S. Mereghetti, L. Sidoli, G. L. Israel

Using the BeppoSAX satellite we have obtained the first secure X-ray detection of the supernova remnant G0.9+0.1. The 1-10 keV spectrum can be described with an absorbed power law with photon index 3 and N_H = 3 times 10^{23} cm^2. The high column density supports a distance similar to that of the Galactic Center. The X-ray emission, with a luminosity L_x =

R. H. Sanders

It is well-known that the application of Newtonian dynamics to an expanding spherical region leads to the correct relativistic expression (the Friedmann equation) for the evolution of the cosmic scale factor. Here, the cosmological implications of Milgrom&#39;s modified Newtonian dynamics (MOND) are considered by means of a similar procedure. Earlier work by

Elena Pian, Andrew S. Fruchter, Louis E. Bergeron, Steve E. Thorsett

We report on Hubble Space Telescope (HST) observations of the optical transient (OT) discovered in the error box of the gamma-ray burst GRB970508. The object was imaged on 1997 June 2 with the Space Telescope Imaging Spectrograph (STIS) and Near-Infrared Camera and Multi-Object Spectrometer (NICMOS). The observations reveal a point-like source with R = 23.1

Chris Fryer, Adam Burrows, Willy Benz

We use a Monte Carlo binary synthesis code to model the formation and evolution of neutron star systems including high-mass X-ray binaries, low-mass X-ray binaries, double neutron star systems and radio pulsars. Our focus is on the signature imprinted on such systems due to natal kicks to neutron stars over and above that imparted by orbital motions. The cod

Carsten van de Bruck

We investigate the peculiar velocity field due to long cosmic strings in several cosmological models and analyse the influence of a nonscaling behaviour of the string network, which is expected in open cosmological models or models with a cosmological constant. It is shown that the deviation of the propability distribution of the peculiar velocity field from

Elena Pian, Giuseppe Vacanti, Gianpiero Tagliaferri, Gabriele Ghisellini

The BL Lac object Mkn 501, one of the only three extragalactic sources (with Mkn 421 and 1ES 2344+514) so far detected at TeV energies, was observed with the BeppoSAX satellite on 7, 11, and 16 April 1997 during a phase of high activity at TeV energies, as monitored with the Whipple, HEGRA and CAT Cherenkov telescopes. Over the whole 0.1-200 keV range the sp

A. Ortiz-Gil, M. Hiesgen, P. Brosche

A new procedure for the reduction of &#34;Carte du Ciel&#34; plates is presented. A typical &#34;Carte du Ciel&#34; plate corresponding to the Bordeaux zone has been taken as an example. It shows triple exposures for each object and the modelling of the data has been performed by means of a non-linear least squares fitting of the sum of three bivariate Gauss

Alberto Alzati, Gian Mario Besana

A long standing conjecture, known to us as the Eisenbud Goto conjecture, states that an n-dimensional variety embedded with degree $d$ in the $N$- dimensional projective space is $(d-(N-n)+1)$-regular in the sense of Castelnuovo-Mumford. In this work the conjecture is proved for all smooth varieties $X$ embedded by the complete linear system associated with

J. M. Landsberg

Let $X\subset P^N$ be a variety (respectively a patch of an analytic submanifold) and let $x\in X$ be a general point. We show that if the projective second fundamental form of $X$ at $x$ is isomorphic to the second fundamental form of a point of a Segre $P^n\times P^m$, $n,m\geq 2$, a Grassmaniann $G(2,n+2)$, $n\geq 4$, or the Cayley plane $OP^2$, then $X$

Sergey Barannikov, Maxim Kontsevich

We construct a generalization of the variations of Hodge structures on Calabi-Yau manifolds. It gives a Mirror partner for the theory of genus=0 Gromov-Witten invariants

David J. Schlegel, Douglas P. Finkbeiner, Marc Davis

We present a full sky 100 micron map that is a reprocessed composite of the COBE/DIRBE and IRAS/ISSA maps, with the zodiacal foreground and confirmed point sources removed. Before using the ISSA maps, we remove the remaining artifacts from the IRAS scan pattern. Using the DIRBE 100 micron and 240 micron data, we have constructed a map of the dust temperature

Dan Maoz, Anuradha Koratkar, Joseph C. Shields, Luis C. Ho

Imaging studies have shown that about 25% of LINER galaxies display a compact nuclear UV source. As part of a program to study the nature of LINERs and their connection to the active galaxy phenomenon, we compare the HST ultraviolet (1150-3200 Ang) spectra of seven such UV-bright LINERs. Data for three of the galaxies (NGC 404, NGC 4569, and NGC 5055) are pr

D. Klemm, V. Moretti, L. Vanzo

A class of metrics solving Einstein&#39;s equations with negative cosmological constant and representing rotating, topological black holes is presented. All such solutions are in the Petrov type-$D$ class, and can be obtained from the most general metric known in this class by acting with suitably chosen discrete groups of isometries. First, by analytical co

Roland Steinbauer

The geometry of impulsive pp-waves is explored via the analysis of the geodesic and geodesic deviation equation using the distributional form of the metric. The geodesic equation involves formally ill-defined products of distributions due to the nonlinearity of the equations and the presence of the Dirac $\de$-distribution in the space time metric. Thus, str

Chueng-Ryong Ji, Robert Kaminski, Leonard Lesniak, Adam Szczepaniak

We present a coupled channel partial wave analysis of nondiffractive S-wave pi+ pi- and K+ K- photoproduction focusing on the KK threshold. Final state interactions are included. We calculate total cross sections, angular and effective mass distributions in both pion-pion and kaon-antikaon channels. Our results indicate that these processes are experimentall

A. A. Slavnov, N. V. Zverev

Abelian fermion models described by the SLAC action are considered on a finite 2d lattice. It is shown that modification of these models by introducing additional Pauli - Villars regularization supresses nonlocal effects and provides agreement with the continuum results in vectorial U(1) models. In the case of chiral fermions the phase of the determinant dif

Karmadeva Maharana

We generalize the method of obtaining the fundamental linear partial differential equations such as the diffusion and Schrodinger equation, Dirac and telegrapher&#39;s equation from a simple stochastic consideration to arrive at certain nonlinear form of these equations. The group classification through one parameter group of transformation for two of these

P. M. Cowdall

We show that the D=6 SU(2) gauged supergravity of van Nieuwenhuizen et al, obtained by dimensional reduction of the D=7 topologically massive gauged supergravity and previously thought not to be dimensionally reducible, can be further reduced to five and four dimensions. On reduction to D=4 one recovers the special case of the SU(2)XSU(2) gauged supergravity

Andreas Blumhofer, Richard Dawid, Johannes Manus

The predictive power of top-condensation models strongly depends on the behaviour of higher dimensional operators. These are analyzed in this paper by an extension of the standard renormalization group (RG) arguments which turns out to be a surprisingly powerful tool. Top-condensation models intermediated by underlying scalar exchange can be shown to be mere

G. Schwarz, A. Kley, J. Neugebauer, M. Scheffler

We have performed total-energy density-functional calculations using first-principles pseudopotentials to determine the atomic and electronic structure of neutral surface and subsurface vacancies at the GaP(110) surface. The cation as well as the anion surface vacancy show a pronounced inward relaxation of the three nearest neighbor atoms towards the vacancy

Guido Cognola

The one-loop contributions to the entropy for a massive scalar field in a Kerr black hole are investigated using an approximation of the metric, which, after a conformal transformation, permits to work in a Rindler-like spacetime. Of course, as for the Schwarzschild case, the entropy is divergent in the proximity of the event horizon.

A. Papa

The surface tension at the deconfinement transition of SU(3) is determined with a parametrized version of the fixed point action of a renormalization group transformation on lattices with temporal extent $N_τ=3$ and 4 and spatial extent $N_σ/N_τ=3$ and 4. A considerable cut-off dependence can be seen in comparison with earlier determinations from tree level

C. Bartolini, G. M. Beskin, A. Guarnieri, N. Masetti

The analysis of the light curves of the optical counterparts of GRB 970228 and GRB 970508 points out remarkable similarities. The spectral distribution obtained from the color indices shows that both the transients became bluer during the increasing stage, and redder after the maximum. A main difference concerns the behaviour of the optical fading which is w

Mahn-Soo Choi, Sung-Ik Lee, M. Y. Choi

We consider a two-dimensional array of ultra-small superconducting grains, weakly coupled by Josephson junctions with large charging energy. We start from an effective action based on a microscopic tunneling Hamiltonian, which includes quasiparticle degrees of freedom, and study the resulting dissipative dynamics of quantum vortices. The equation of motion f

Andre Lukas, Burt A. Ovrut, Daniel Waldram

The low-energy D=4, N=1 effective action of the strongly coupled heterotic string is explicitly computed by compactifying Horava-Witten theory on the deformed Calabi-Yau three-fold solution due to Witten. It is shown that, to order kappa^{2/3}, the Kahler potential is identical to that of the weakly coupled theory. Furthermore, the gauge kinetic functions ar

H. -W. Chen, K. M. Lanzetta, J. K. Webb, X. Barcons

We present initial results of a program to obtain and analyze HST WFPC2 images of galaxies identified in an imaging and spectroscopic survey of faint galaxies in fields of HST spectroscopic target QSOs. We measure properties of 87 galaxies, of which 33 are associated with corresponding \lya absorption systems and 24 do not produce corresponding \lya absorpti

Yeuk-Kwan E. Cheung, Zheng Yin

When a D-brane wraps around a cycle of a curved manifold, the twisting of its normal bundle can induce chiral asymmetry in its worldvolume theory. We obtain the general form of the resulting anomalies for D-branes and their intersections. They are not cancelled among themselves, and the standard inflow mechanism does not apply at first sight because of their

J. Schaffner-Bielich, A. P. Vischer

We discuss the possibility, that multiply charmed exotics are produced in ultrarelativistic heavy ion collisions. Production probabilities at RHIC are estimated and found to be large enough to allow for the possible detection of single and double charmed exotics. We demonstrate that charm matter is bound due to an attractive one-gluon exchange potential. Fur

Henrik Aratyn, Ashok Das

We study, systematically, the properties of the supersymmetric AKNS (sAKNS) hierarchy. In particular, we discuss the Lax representation in terms of a bosonic Lax operator and some special features of the equations and construct the bosonic local charges as well as the fermionic nonlocal charges associated with the system starting from the Lax operator. We ob

Y. S. Kim

It is shown that the time-energy uncertainty relation can be combined into the position-momentum uncertainty relation covariantly in the quark model of hadrons. This leads to a Lorentz-invariant form of the uncertainty relations. This model explains that the quark model and the parton model are two different manifestations of the same covariant model. In par

Weiqiang Wang

We construct and study in detail various dual pairs acting on some Fock representations between a finite dimensional Lie group and a completed infinite rank affine algebra associated to an infinite affine Cartan matrix. We give explicit decompositions of a Fock representation into a direct sum of irreducible isotypic subspaces with respect to the action of a

Ursula Carow-Watamura, Satoshi Watamura

We find that there is an alternative possibility to define the chirality operator on the fuzzy sphere, due to the ambiguity of the operator ordering. Adopting this new chirality operator and the corresponding Dirac operator, we define Connes&#39; spectral triple on the fuzzy sphere and the differential calculus. The differential calculus based on this new sp

Michel Dubois-Violette

We study the generalized homology associated with a nilpotent endomorphism $d$ satisfying $d^N=0$. For simplicial modules we construct such nilpotent endomorphisms and we prove a general result relating the corresponding generalized homologies to the ordinary homology. We also discuss the generalization of the notion of graded differential algebra in this co

R. Ramachandran

It is argued that the three families of quarks and leptons are the building blocks of all matter and all forces (leaving out gravity) among them are mediated by photons ($γ$), the weak bosons ($W^\pm$ and $Z$) and the gluons.

U. van Kolck, M. C. M. Rentmeester, J. L. Friar, T. Goldman

Leading-order electromagnetic loop corrections to the one-pion-exchange potential are computed within the framework of chiral perturbation theory. These corrections generate an effective nucleon-nucleon potential, $V_{πγ}$, which supplements the sum of OPEP and the nucleon-nucleon Coulomb potential. This potential is charge dependent and its construction is

P. G. Blunden, Y. Okuhara, A. S. Raskin

The equations of motion for a massive spin-3/2 Rarita-Schwinger field in a finite-range, central, Lorentz scalar potential are developed. It is shown that the resulting density may not be everywhere positive definite.

Ulrich Heinz

By measuring hadronic single-particle spectra and two-particle correlations in heavy-ion collisions, the size and dynamical state of the collision fireball at freeze-out can be reconstructed. I discuss the relevant theoretical methods and their limitations. By applying the formalism to recent pion correlation data from Pb+Pb collisions at CERN we demonstrate

Manoelito M. de Souza

The classical electromagnetic field of a spinless point electron is described in a formalism with extended causality by discrete finite transverse point-vector fields with discrete and localized point interactions. These fields are taken as a classical representation of photons, ``classical photons&#34;. They are all transversal photons; there are no scalar

Bernard de Wit, Kasper Peeters, Jan Plefka

Motivated by manifest Lorentz symmetry and a well-defined large-N limit prescription, we study the supersymmetric quantum mechanics proposed as a model for the collective dynamics of D0-branes from the point of view of the 11-dimensional supermembrane. We argue that the continuity of the spectrum persists irrespective of the presence of winding around compac

Wang-Chang Su

An &#34;expanded&#34; description is introduced to examine the spinor-monopole identification proposed by Strassler for four-dimensional $\cal N$ = 1 supersymmetric Spin(10) gauge theories with matter in F vector and N spinor representations. It is shown that a Z_2 monopole in the &#34;expanded&#34; theory is associated with massive spinors of the Spin(10) t

P. Claus, B. de Wit, M. Faux, B. Kleijn

We discuss the coupling of vector-tensor multiplets to N=2 supergravity.

B. Chakraborty

Recently it has been shown by Cho and Kimm that the gauged $CP^1$ model, obtained by gauging the global SU(2) group of $CP^1$ model and adding a corresponding Chern-Simons term, has got its own soliton. These solitons are somewhat distinct from those of pure $CP^1$ model, as they cannot always be characterised by $π_2(CP^1)=Z$. In this paper, we first carry

D. Korotkin, H. Samtleben

Dimensional reduction of various gravity and supergravity models leads to effectively two-dimensional field theories described by gravity coupled G/H coset space sigma-models. The transition matrices of the associated linear system provide a complete set of conserved charges. Their Poisson algebra is a semi-classical Yangian double modified by a twist which

H. Ikemori, S. Kitakado, H. Nakatani, H. Otsu

A particle in quantum mechanics on manifolds couples to the induced topological gauge field that characterises the possible inequivalent quantizations. For instance, the gauge potential induced on $S^2$ is that of a magnetic monopole located at the center of $S^2$. We find that the gauge potential induced on $S^3$ ($S^{2n+1}$) is that of a meron (generalized

Robert de Mello Koch

In this letter we study $D$ particle quantum mechanics on a torus in the limit that one or more cycles of the torus have a zero length.

N. Kim, Soo-Jong Rey

M(atrix) theory description is investigated for M-theory compactified on non-orientable manifolds. Relevant M(atrix) theory is obtained by Fourier transformation in a way consistent with T-duality. For nine-dimensional compactification on Klein bottle and Möbius strip, we show that M(atrix) theory is (2+1)-dimensional ${\cal N} = 8$ supersymmetric U(N) gauge

M. A. Ivanov, T. Mizutani

We report on a confined quark model calculation of the transition form factors for the radiative decays of η(η&#39;)->γl^+l^- and η(η&#39;)->γπ^+π^-. The η-η&#39; mixing angle θ_P is determined from the set of data on the electromagnetic η(η&#39;) decays. It is found that θ_P\sim -16.5. The analysis of the dipionic mass distribution in the decay η&#39;->γπ^+

Yong-Yeon Keum, Ulrich Nierste

We calculate penguin contributions to the lifetime splitting between the B_s and the B_d meson. In the Standard Model the penguin effects are found to be opposite in sign, but of similar magnitude as the contributions of the current-current operators, despite of the smallness of the penguin coefficients. We predict tau(B_s)/tau(B_d) -1 = ( -1.2 +/- 10.0 ) *

D. Ebert

Path integral techniques in collective fields are shown to be a useful analytical tool to reformulate a field theory defined in terms of microscopic quark (gluon) degrees of freedom as an effective theory of collective boson (meson) fields. For illustrations, the path integral bosonization approach is applied to derive a (non)linear sigma model from a Nambu-

M. R. Ahmady, E. Kou, A. Sugamoto

We propose a mechanism which can explain the large BR(B-> X_s eta&#39;)~ 10^(-3) observed by CLEO. In this mechanism, eta&#39; is produced by the fusion of two gluons, one from QCD penguin b->sg and the other one emitted by the light quark inside the B meson. The inclusive decay rate which is calculated via using the factorization assumption, can easily acco

T. Gehrmann

The production of $W^{\pm}$ and $Z^0$ bosons in collisions of longitudinally polarized protons allows to access various combinations of the polarized quark distributions from the study of double and single spin asymmetries. We compute the ${\cal O}(α_s)$ corrections to these asymmetries as function of the vector boson rapidity $y$ in the hadron-hadron centre

D. Ebert

The method of path integral hadronization is applied to a local quark-diquark toy model in order to derive an effective chiral meson-baryon Lagrangian. Further generalizations to models including both scalar and axial-vector diquarks as well as nonlocal interactions are discussed.

Gerhard A. Schuler

An extended version of the Monte Carlo program GALUGA is presented for the computation of two-photon production in $\e^+\e^-$ collisions. Functions implemented for the five $γ^\starγ^\star$ structure functions now include several ansätze of the total hadronic cross section based on the BFKL--Pomeron and various Regge-like models. In addition, structure funct

M. Anselmino, M. Bertini, C. Burgard, F. Caruso

Some data on the ratio of vector to vector + pseudoscalar mesons, V/(V+P), and the probability of helicity zero vector states, rho_00, are now available from LEP. A possible relation between these two quantities and their interpretation in terms of polarized fragmentation functions are discussed; numerical estimates are given for the relative occupancies of

D. Ebert, R. N. Faustov, V. O. Galkin

The energetic exclusive two-body nonleptonic decays of B mesons are investigated in the framework of the relativistic quark model within the factorization approximation.

N. Pott

The anomalous dimensions of four-quark operators $(\bar q_i q_j)_{V-A} (\bar q_k q_l)_{V-A}$ are calculated in the large $N_f$ limit. As expected, the result is a convergent series without renormalon ambiguities. Using the approximation of &#34;Naive Nonabelianization&#34;, an additional all-order contribution to the anomalous dimension matrix is obtained wh

Chris Michael

Lattice QCD determinations appropriate to hadron spectroscopy are reviewed with emphasis on the glueball and hybrid meson states in the quenched approximation. Hybrids are discussed for heavy and for light quarks. The effects of sea quarks (unquenching) are explored. Heavy-light systems are presented - particularly excited B mesons.

T. Gehrmann

The results of a recent calculation of the QCD corrections to the longitudinally polarized Drell-Yan process are summarized. In addition to the parity conserving double spin asymmetry which is already accessible in the Drell-Yan production of lepton pairs at fixed target energies, we consider parity violating single spin asymmetries appearing only in the pro

J. Bartels, A. De Roeck, C. Ewerz, H. Lotter

We present a numerical estimate of the $γ^* γ^*$ total cross section at the designed 500 GeV $e^+e^-$ Linear Collider, based upon the BFKL Pomeron. We find that the event rate is substantial provided electrons scattered under small angles can be detected, and a measurement of this cross section provides an excellent test of the BFKL Pomeron.

S. P. Baranov, M. G. Ryskin, T. Gehrmann

A successful interpretation of the cross sections for elastic and inelastic vector meson production can be made if one assumes the underlying dynamics to be governed by hard partonic subprocesses. Extending these partonic approaches to longitudinally polarized electron-proton collisions, we estimate the expected production asymmetries at the HERA collider. T

P. J. Mulders

In this contribution I discuss transverse momentum dependent quark distributions and their operator structure. Some of the experimental signatures, in particular in Drell-Yan scattering, are given.

J. I. Illana

The MSSM predictions at the one-loop level for the weak dipole moments of the τlepton and the b quark are presented. The imaginary part of the AWMDM is of the order of the SM contribution whereas the real part may be a factor 5 (20) larger for the τ(b) in the high \tanβscenario, still a factor five below the QCD contribution in the b case. More interestingly

R. Jakob, P. J. Mulders, J. Rodrigues

Estimates for leading and non-leading `twist&#39; distribution functions are obtained within the framework of a diquark spectator model using a non-local operator representation.

J. G. Contreras

A set of FORTRAN routines to perform a fast simulation of a HERA--like detector including the smearing of the $z$ coordinate of the interaction vertex, the simulation of a tracker system, of an electromagnetic and of a hadronic calorimeter is presented.

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

The Coulomb corrections to the helicity amplitudes of high-energy photon splitting are examined. The consideration is based on the amplitudes obtained exactly in the parameter Zαwithin the quasiclassical approach valid for small angles between all photon momenta. We consider the case when the transverse momenta of both final photons are much larger than the

J. Lykken, T. Montroy, S. Willenbrock

The hypercharges of the fermions are not uniquely determined in SO(10) grand unification, but rather depend upon which linear combination of the two U(1) subgroups of SO(10) > SU(3) X SU(2) X U(1) X U(1) remains unbroken. We show that, in general, a given hypercharge assignment can be obtained only with very high-dimensional Higgs representations. The observ

John N. Bahcall

Neutrino absorption cross sections for 71Ga are calculated for all solar neutrino sources with standard energy spectra, and for laboratory sources of 51Cr and 37Ar; the calculations include, where appropriate, the thermal energy of fusing solar ions and use improved nuclear and atomic data. The ratio, R, of measured (in GALLEX and SAGE) to calculated 51Cr ca

P. Butera, M. Comi

High temperature expansions for the susceptibility and the second correlation moment of the classical N-vector model (also known as the O(N) symmetric Heisenberg classical spin model or the as the lattice O(N) nonlinear sigma model) on the square lattice are extended from order beta^{14} to beta^{21} for arbitrary N. For the second field derivative of the su

Rajan Gupta

This talk summarizes the status of the calculations of $B_K$, $B_7$, $B_8$, and $B_s$, done in collaboration with T. Bhattacharya, G. Kilcup, and S. Sharpe. Results for staggered, Wilson, and Clover fermions are presented.

L. Herrera, J. Martinez

Two relativistic models for collapsing spheres at different stages of evolution, which include pre-relaxation processes, are presented. The influence of relaxation time on the outcome of evolution in both cases is exhibited and established. It is shown that relaxation processes can drastically change the final state of the collapsing system. In particular, t

J. W. Maluf

It has been shown recently that within the framework of the teleparallel equivalent of general relativity (TEGR) it is possible to define the energy density of the gravitational field. The TEGR amounts to an alternative formulation of Einstein&#39;s general relativity, not to an alternative gravity theory. The localizability of the gravitational energy has b

Patricio. S. Letelier, Samuel R. Oliveira

Solutions to the Einstein equation that represent the superposition of static isolated bodies with axially symmetry are presented. The equations nonlinearity yields singular structures (strut and membranes) to equilibrate the bodies. The force on the strut like singularities is computed for a variety of situations. The superposition of a ring and a particle

S. Bonazzola, J. Frieben, E. Gourgoulhon

An analytical scheme and a numerical method in order to study the effects of general relativity on the viscosity driven secular bar mode instability of rapidly rotating stars are presented. The approach consists in perturbing an axisymmetric and stationary configuration and studying its evolution by constructing a series of triaxial quasi-equilibrium configu

M. Yu. Konstantinov

The problems causality and causality violation in topologically nontrivial space-time models are considered. To this end the mixed boundary problem for traversable wormhole models is formulated and the influence of the boundary conditions on the causal properties of space-time is analyzed

Nathanial P. Brown

It is shown that if A is an AF algebra then a crossed product of A by the integers can be embedded into an AF algebra if and only if the crossed product is stably finite. This equivalence follows from a simple K-theoretic characterization of AF embeddability. It is then shown that if a crossed product of an AF algebra by the integers is AF embeddable then th

Kirill Mackenzie, Ping Xu

We extend the calculus of multiplicative vector fields and differential forms and their intrinsic derivatives from Lie groups to Lie groupoids; this generalization turns out to include also the classical process of complete lifting from arbitrary manifolds to tangent and cotangent bundles. Using this calculus we give a new description of the Lie bialgebroid

Mikito Koga, Wenjian Liu, Michael Dolg, Peter Fulde

Anderson models, based on quantum chemical studies of the molecule of U(C_8H_8)_2, are applied to investigate the problem of an U impurity in a metal. The special point here is that the U 5f-orbitals are divided into two subsets: an almost completely localized set and a considerably delocalized one. Due to the crystal field, both localized and delocalized U

S. E. Barnes

Small ferromagnets and anti-ferromagnets with an easy-plane anisotropy have a ground to first excited state (tunnel) splitting which is quasi-periodic in the magnitude of a field applied perpendicular to a principal anisotropy axis. The associated oscillations in thermodynamic quantities might be used to prove the existence of a coherent ground state even wh

Shirish M. Chitanvis

We have formulated a theory of self-assembly based on the notion of local gauge invariance at the mesoscale. Local gauge invariance at the mesoscale generates the required long- range entropic forces responsible for self-assembly in binary systems. Our theory was applied to study the onset of mesostructure formation above a critical temperature in estane, a

Asok K. Sen

We study localization properties of a one-dimensional disordered system characterized by a random non-hermitean hamiltonian where both the randomness and the non-hermiticity arises in the local site-potential; its real part being random, and a constant imaginary part implying the presence of either a coherent absorption or amplification at each site. While t