April 1997 arXiv papers — page 9

A. L. Barabanov, Yu. V. Gaponov, B. V. Danilin, N. B. Shul'gina

Angular distribution of neutrinos (recoil nucleus) in muon capture for an allowed Gamov-Teller transition is considered by taking account of hyperfine effects. This angular distribution is shown to include a correlation of the form P_2(cos A), where A is the angle between the neutrino momentum and the axis specifying the orientation of the initial mesic atom

S. A. Sofianos, S. A. Rakityansky, M. Braun

The η-meson collision with light nuclei, ^2H, ^3H, ^3He, and ^4He, is considered on the basis of a microscopic approach which utilises Faddeev type and Lippmann-Schwinger equations. The nuclear hamiltonian is approximated by the finite rank approximation which amounts to the coherent approximation. The η-nucleus scattering length and the resonance and bound-

Tomoko Asaga, Takehisa Fujita, Kaori Ito

We calculate the hyperfine structure constant for the Eu isotopes with shell model wave functions. The calculated results are compared with those predicted by the Moskowitz-Lombardi (M-L) empirical formula. It turns out that the two approaches give the very different behaviors of the hfs constants in the isotope dependence. This should be easily measured by

Ta Lê Loi

We prove the existence of Verdier stratifications for sets definable in any o-minimal structure on (R, +, .). It is also shown that the Verdier condition (w) implies the Whitney condition (b) in o-minimal structures on (R, +, .). As a consequence the Whitney Stratification Theorem holds. The existence of (wf)-stratification of functions definable in polynomi

M. Moriconi, K. Schoutens

We briefly review the general structure of integrable particle theories in 1+1 dimensions having N=1 supersymmetry. Examples are specific perturbed superconformal field theories (of Yang-Lee type) and the N=1 supersymmetric sine-Gordon theory. We comment on the modifications that are required when the N=1 supersymmetry algebra contains non-trivial topologica

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

QCD is constructed as a lattice gauge theory in which the elements of the link matrices are represented by non-commuting operators acting in a Hilbert space. The resulting quantum link model for QCD is formulated with a fifth Euclidean dimension, whose extent resembles the inverse gauge coupling of the resulting four-dimensional theory after dimensional redu

S. Elitzur, A. Giveon, D. Kutasov, E. Rabinovici

We discuss some aspects of the relation between space-time properties of branes in string theory, and the gauge theory on their worldvolume, for models invariant under four supercharges in three and four dimensions. We show that a simple set of rules governing brane dynamics reproduces many features of gauge theory. We study theories with $U(N_c)$, $SO(N_c)$

Jani Lukkarinen

We propose a method for the numerical computation of microcanonical expectation values--i.e. averages over energy eigenstates with the same eigenvalue-without any prior knowledge about the spectrum of the Hamiltonian. This is accomplished by first defining a new Gaussian ensemble to approximate the microcanonical one. We then develop a ``lattice theory'&

Harunobu Kubo

A difference operator realization of quantum deformed oscillator algebra $H_q(1)$ with a Casimir operator freedom is introduced. We show that this $H_q(1)$ have a nonlinear mapping to the deformed quantum su(2) which was introduced by Fujikawa et al. We also examine the cyclic representation obtained by this difference operator realization and the possibilit

M. Krämer, T. Plehn, M. Spira, P. M. Zerwas

We present the cross section for pair production of scalar leptoquarks $LQ$ in $p\bar{p}$ collisions, $p+\bar{p} \to LQ + \bar{LQ} + X$, at the Fermilab Tevatron in next-to-leading order QCD. Including the higher-order corrections stabilizes the theoretical prediction and increases the size of the cross section for renormalization/factorization scales close

Chris Quigg

Questions on the top quark posed for the 1996 DPF/DPB Summer Study on New Directions for High-Energy Physics (Snowmass 96).

Sergio Lupia, Wolfgang Ochs

Charged particle energy spectra in e+e- annihilation are compared with the analytical predictions from the QCD evolution equation in the Modified Leading Log Approximation. With the nonperturbative initial condition shifted down to threshold as suggested by the Local Parton Hadron Duality picture a good description of the data from the lowest up to highest a

Wilfried Buchmuller, Daniel Wyler

Forces beyond those of the standard model may manifest themselves at low energies as four-fermion contact interactions. If these new forces are independent of colour and flavour quantum numbers including baryon and lepton number, then all low energy constraints, arising from quark-lepton universality, flavour-changing neutral currents and atomic parity viola

T. Matsushima

The mass differences in all neutral pseudo scalar mesons and CP violations associated with the mixings are investigated in the context of the fermion- boson-type subquark model. These phenomena are unifyingly explained by the neutral scalar subquark exchanges between two quarks inside the present meson. It is predicted that the mass differences and CP violat

Georg G. Raffelt

Astrophysical and cosmological arguments and observations give us the most restrictive constraints on neutrino masses, electromagnetic couplings, and other properties. Conversely, massive neutrinos would contribute to the cosmic dark-matter density and would play an important role for the formation of structure in the universe. Neutrino oscillations may well

Yu. A. Golubkov, R. V. Konoplich

We carry out a detailed analysis of fluxes of cosmic ray antiprotons, positrons, electrons and photons to be expected from the annihilation of relic heavy neutrinos in the galactic halo. The spectra of particles are evaluated by Monte Carlo simulation. The results of calculations show that the investigation of cosmic ray positron spectra at high energies cou

Alessandro Bravar, Krzysztof Kurek, Roland Windmolders

POLDIS is a Monte Carlo program for polarized (semi-inclusive) deep inelastic scattering (DIS). Unpolarized DIS events are generated with the existing lepto-production event generators LEPTO for DIS and AROMA for Heavy Flavor production. The relevant spin asymmetries are computed at partonic level to first order in alpha_s for each generated event, and are t

M. S. Baek, S. Y. Choi, C. S. Kim

We provide a detailed, model-independent, study for CP violation effects due to the T-odd top-quark electric dipole moment (EDM) and weak dipole moment (WDM) in the top-quark pair production via $e^+e^-$ and two-photon annihilation at a next $e^+e^-$ linear collider (NLC). There are two methods in detecting CP violation effects in these processes. One method

Marco Spaans

A formalism is presented to construct a non-perturbative Grand Unified Theory when gravitational Planck-scale phenomena are included. The fundamental object on the Planck scale is the three-torus T^3 from which the known properties of superstrings, such as the geometric action and duality, follow directly. The low energy theory is 11-dimensional and compacti

S. Mignemi

We study a four-dimensional gauge theory of the Poincaré group with topological action which generalizes some well-known two-dimensional gravity models. We classify the spherically symmetric solutions and discuss the perturbative propagation of excitations around flat spacetime.

Gerhard Mack

In these lectures I propose to push Einstein's principle of coordinate independence to the extreme in order to restrict the possible form of fundamental equations of motion in physics. I start from nearly tautological system theoretic axioms. They provide a minimal amount of a priori structure which is thought to be characteristic of human thinking in ge

Sanjoy K. Sarker, Philip W. Anderson

A simple interlayer pair tunneling is solved exactly. We find that in the normal state spin-1/2 particle and hole excitations are gapped. But the state is an unusual metal, characterized by novel fermionic spin zero and charge +2e and -2e excitations that exist about their own Fermi surfaces. The model is consistent with a number of properties of the underdo

B. L. Altshuler, L. S. Levitov

Transition from regular to chaotic dynamics in a crystal made of singular scatterers $U(r)=λ|r|^{-σ}$ can be reached by varying either sigma or lambda. We map the problem to a localization problem, and find that in all space dimensions the transition occurs at sigma=1, i.e., Coulomb potential has marginal singularity. We study the critical line sigma=1 by me

D. Lilliehook, K. Lejnell, A. Karlhede, S. L. Sondhi

We have investigated quantum Hall skyrmions at filling factor ν=1 carrying more than one unit of topological, and hence electric, charge. Using a combination of analytic and numerical methods we find the counterintuitive result that when the Zeeman energy is tuned to values much smaller than the interaction energy (g μ_B B/(e^2/ε\ell) < 9*10^{-5}),the creati

T. J. Newman

An exact analysis is performed for the two-point correlation function C(r,t) in dissipative Burgers turbulence with bounded initial data, in arbitrary spatial dimension d. Contrary to the usual scaling hypothesis of a single dynamic length scale, it is found that C contains two dynamic scales: a diffusive scale l_{D} \sim t^{1/2} for very large r, and a supe

Paul A. Houle

We study anharmonic localization in a periodic five atom chain with quadratic-quartic spring potential. We use discrete symmetries to eliminate the degeneracies of the harmonic chain and easily find periodic orbits. We apply linear stability analysis to measure the frequency of phonon-like disturbances in the presence of breathers and to analyze the instabil

C. L. Kane, E. J. Mele, R. S. Lee, J. E. Fischer

Nonchiral single wall carbon nanotubes with an &#34;armchair&#34; wrapping are theoretically predicted to be conducting, and high purity samples consisting predominantly of these tubes exhibit metallic behavior with an intrinsic resistivity which increases approximately linearly with temperature over a wide temperature range. Here we study the coupling of th

D. Chang, C. -Y. Mou, B. Rosenstein, C. L. Wu

We describe effects of anisotropy caused by the crystal lattice in d-wave superconductors using effective free energy approach in which only one order parameter, the d-wave order parameter field, is used. All the effects of rotational symmetry breaking, including that of the s-wave mixing, can be parametrized by a single four derivative term. We find solutio

David G. Shelton, Alexei M. Tsvelik

In gapped spin ladder and spin-Peierls systems the introduction of disorder, for example by doping, leads to the appearance of low energy midgap states. The fact that these strongly correlated systems can be mapped onto one dimensional noninteracting fermions provides a rare opportunity to explore systems which have both strong interactions and disorder. In

F. Matsubara, A. Sato, O. Koseki, T. Shirakura

We have proposed a cluster heat bath method in Monte Carlo simulations of Ising models in which one of the possible spin configurations of a cluster is selected in accordance with its Boltzmann weight. We have argued that the method improves slow relaxation in complex systems and demonstrated it in an axial next-nearest-neighbor Ising(ANNNI) model in two-dim

Alexander van Oudenaarden, M. H. Devoret, E. H. Visscher, Yu. V. Nazarov

The conductance fluctuations of a metallic wire which is interrupted by a small tunnel junction has been explored experimentally. In this system, the bias voltage V, which drops almost completely inside the tunnel barrier, is used to probe the energy dependence of conductance fluctuations due to disorder in the wire. We find that the variance of the fluctuat

Parongama Sen

For random percolation at p_c, the probability distribution P(n) of the number of spanning clusters (n) has been studied in large scale simulations. The results are compatible with $P(n) \sim \exp(-an^2)$ for all dimensions. We also study the variation of the average size (mass) of the spanning clusters when there are more than one spanning cluster. While th

S. Gluzman, V. I. Yukalov

We consider the method of self-similar renormalization for calculating critical temperatures and critical indices. A new optimized variant of the method for an effective summation of asymptotic series is suggested and illustrated by several different examples. The advantage of the method is in combining simplicity with high accuracy.

Michael Weiss, Franz-Josef Elmer

Wearless friction is investigated in a simple mechanical model called Frenkel-Kontorova-Tomlinson model. We have introduced this model in [Phys. Rev. B, Vol. 53, 7539 (1996)] where the static friction has already been considered. Here the model is treated for constant sliding speed. The kinetic friction is calculated numerically as well as analytically. As a

C. A. Marsh, G. Backx, M. H. Ernst

The algorithm for Dissipative Particle Dynamics (DPD), as modified by Espagnol and Warren, is used as a starting point for proving an H-theorem for the free energy and deriving hydrodynamic equations. Equilibrium and transport properties of the DPD fluid are explicitly calculated in terms of the system parameters for the continuous time version of the model.

Kevin Knight, Jonathan Graehl

It is challenging to translate names and technical terms across languages with different alphabets and sound inventories. These items are commonly transliterated, i.e., replaced with approximate phonetic equivalents. For example, &#34;computer&#34; in English comes out as &#34;konpyuutaa&#34; in Japanese. Translating such items from Japanese back to English

Beverly J. Smith, Suzanne C. Madden

We have measured the strengths of the [C II] 158 micron, [N II] 122 micron, and CO (1 - 0) lines from five low blue luminosity spiral galaxies in the Virgo Cluster, using the Infrared Space Observatory and the NRAO 12m millimeter telescope. Two of the five galaxies have high L([C II)]/L(CO) and L(FIR)/L(CO) ratios compared to higher mass spirals. These two g

Dong Lai

Recent timing observations have revealed the presence of orbital precession due to spin-orbit coupling and rapid orbital decay due to dynamical tidal interaction in the PSR J0045-7319/B-star binary system. They can be used to put concrete constraints on the age, initial spin and velocity of the neutron star.

Abraham Loeb, Zoltan Haiman

We quantify the consequences of intergalactic dust produced by the first Type II supernovae in the universe. The fraction of gas converted into stars is calibrated based on the observed C/H ratio in the intergalactic medium at z=3, assuming a Scalo mass function for the stars. The associated dust absorbs starlight energy and emits it at longer wavelengths. F

Dong Lai

We study the effect of rotation on the excitation of internal oscillation modes of a star by the external gravitational potential of its companion. Unlike the nonrotating case, there are difficulties with the usual mode decomposition for rotating stars because of the asymmetry between modes propagating in the direction of rotation and those propagating oppos

C. S. Reynolds

X-ray spectroscopy of Seyfert 1 galaxies often reveal absorption edges resulting from photoionized gas along the line-of-sight to the central engine, the so-called warm absorber. I discuss how recent ASCA observations of warm absorber variability in MCG-6-30-15 can lead us to reject a one-zone model and, instead, have suggested a multi-zone warm absorber. Th

Dong Lai, Edwin E. Salpeter

The outermost layers of some neutron stars are likely to be dominated by hydrogen, as a result of fast gravitational settling of heavier elements. These layers directly mediate thermal radiation from the stars, and determine the characteristics of X-ray/EUV spectra. For a neutron star with surface temperature $T\lo 10^6$ K and magnetic field $B\go 10^{12}$ G

J. Einasto, M. Einasto, P. Frisch, S. Gottlöber

We investigate properties of the correlation function of clusters of galaxies using geometrical models. On small scales the correlation function depends on the shape and the size of superclusters. On large scales it describes the geometry of the distribution of superclusters. If superclusters are distributed randomly then the correlation function on large sc

O. Almaini, A. C. Fabian

We estimate the number of AGN among the galaxies in the Hubble Deep Field (HDF). The recent discovery of a class of X-ray luminous narrow emission-line galaxies has provided a possible explanation for the origin of the X-ray background (XRB), although the nature of the activity is still unresolved. By extrapolating the observed X-ray number count distributio

J. Einasto, M. Einasto, P. Frisch, S. Gottlöber

We use rich clusters of galaxies in the Northern and Southern Galactic hemispheres up to a redshift z=0.12 to determine the cluster correlation function. We show that superclusters of galaxies and voids between them form a moderately regular network. As a result the correlation function determined for clusters located in rich superclusters oscillates: it has

Volker Springel, Simon D. M. White

A new method is presented to obtain a non-parametric maximum likelihood estimate of the luminosity function and the selection function of a flux limited redshift survey. The method parameterizes the selection function as a series of step-wise power laws and allows possible evolution of the luminosity function. We also propose a new technique to estimate the

S. M. Kanbur, M. A. Hendry, D. Clarke

In this paper we confirm the existence of period-luminosity (PL) and period-luminosity-colour (PLC) relations at maximum light for O and C Mira variables in the LMC. We demonstrate that in the J and H bands the maximum light PL relations have a significantly smaller dispersion than their counterparts at mean light, while the K band and bolometric PL relation

A. V. Gurevich, K. P. Zybin

A new model of gamma radiation (GR) generated by neutralino annihilation in neutralino stars (NeS) is proposed. Diffuse Galactic and extragalactic GR is calculated for this model and is shown to be in a reasonable agreement with observations. The point source component (P) is picked out among nonidentified discrete gamma sources from EGRET catalog. This comp

A. V. Gurevich, K. P. Zybin

A new model of gamma bursts (GB) generated by MACHO&#39;s in the form of noncompact dark matter halo objects (NO) is proposed. The model explain well the spherical symmetry, $log N - log S$ curve of GB absolutely identically to the well-known giant dark matter halo (GDMH) model. The main difficulty of GDMH model -- the lack of neutron stars in our galactic h

Paolo Catelan, Tom Theuns

The formalism that describes the non-linear growth of the angular momentum L of protostructures from tidal torques in a Friedmann Universe, as developed in a previous paper, is extended to include non-Gaussian initial conditions. We restrict our analysis here to a particular class of non-Gaussian primordial distributions, namely multiplicative models. In suc

Gilles Chabrier, Isabelle Baraffe

We present extensive calculations of the structure and the evolution of low-massstars in the range 0.07-0.8 $\msol$, for metallicities $-2.0\le \mh \le 0.0$. These calculations are based on the most recent description of the microphysics characteristic of these dense and cool objects and on the lattest generation of grainless non-grey atmosphere models. We e

Philip Candelas, Eugene Perevalov, Govindan Rajesh

We study F-theory compactified on elliptic Calabi-Yau threefolds that are realised as hypersurfaces in toric varieties. The enhanced gauge group as well as the number of massless tensor multiplets has a very simple description in terms of toric geometry. We find a large number of examples where the gauge group is not a subgroup of E8xE8, but rather, is much

M. A. Halasz, J. C. Osborn, J. J. M. Verbaarschot

We introduce three universality classes of chiral random matrix ensembles with a nonzero chemical potential and real, complex or quaternion real matrix elements. In the thermodynamic limit we find that the distribution of the eigenvalues in the complex plane does not depend on the Dyson index, and is given by the solution proposed by Stephanov. For a finite

N. Itzhaki

We consider string theory corrections to 4D black holes which solve the 5D vacuum Einstein equations. We find that the corrections vanish only for the extremal electric solution. We also show that for the non-extremal electric black hole the mass corrections are related to the charge corrections. The implications to string states counting and the corresponde

Wenji Deng, P. M. Hui

This paper has been withdrawn by Wenji Deng (e-mail: phwjdeng@scut.edu.cn) for further modification at Oct. 12, 1998. {PACS: 03.75.Fi, 05.30.Jp.64.60.-i, 32.80.Pj}

M. Kapranov

Recently, L.Rozansky and E.Witten (hep-th/9612216) associated to any hyperKaehler manifold X a system of &#34;weights&#34; (numbers, one for each trivalent graph) and used them to construct invariants of topological 3-manifolds. We give a very simple cohomological definition of these weights in terms of the Atiyah class of X (the obstruction to existence of

Alexandre Soloviev

We give a new realization of $Y(sl_3)$ via Cartan-Weyl elements. An algebraic description of Yangian Double $DY(sl_3)$, explicit comultiplication formulas and universal R-matrix are obtained in these terms.

Piljin Yi

We consider the Witten index ${\cal I}= Tr (-1)^F$ of SU(2) Super-Yang-Mills quantum mechanics (SYMQ) with N=16, 8, 4 supersymmetries. The theory governs the interactions between a pair of D-branes under various circumstances, and our goal is to count the number of the threshold bound states directly from the low-energy effective theory. The string theory an

Glennys R. Farrar

Several supersymmetry breaking mechanisms do not produce dimension-3 operators. I show here that this scenario is consistent with present observations and has several significant virtues: i) When there are no dimension-3 SUSY-breaking operators there is no SUSY-CP problem. ii) SUSY-breaking need not occur through gauge singlets, so that the cosmological prob

Glennys R. Farrar

An attractive class of SUSY-breaking mechanisms predicts a photino mass of order 1 GeV. Relic photinos can naturally account for the observed dark matter. Detection of these light photinos is discussed and contrasted with conventional WIMPs. In this scenario the gluino mass is about 100 MeV. The lightest gluino-containing baryon could account for the recentl

Vladimir S. Mashkevich

This paper is a continuation of the papers [gr-qc/9409010, gr-qc/9505034, gr-qc/9603022, gr-qc/9609035, gr-qc/9609046]. The introduction of a prior, i.e., predynamical global geometry of spacetime manifold is substantiated, and the geometry is specified. The manifold is an infinite four-cylinder, or tube in the five-dimensional Euclidean space, the orthogona

Ing-Jye Hwang, Seungoh Ryu, D. Stroud

We study the flux noise $S_Φ(ω)$ and finite frequency conductivity $σ_1(ω)$ in two dimensional unfrustrated Josephson junction arrays (JJA&#39;s), by numerically solving the equations of the coupled overdamped resistively-shunted-junction model with Langevin noise. We find that $S_Φ(ω)\propto ω^{-3/2}$ at high frequencies $ω$ and flattens at low $ω$, indicat

Qiming Li, C. M. Soukoulis, I. Zambetaki, E. N. Economou

The localization behavior of the Anderson model with anisotropic hopping integral t for weakly coupled planes and weakly coupled chains is investigated both numerically with the transfer matrix method and analytically within the self-consistent theory of localization. It is found that the mobility edge is independent of the propagating direction. However, th

Eli Waxman

Cosmological fireball models of gamma-ray bursts (GRBs) predict delayed emission, ``after-glow,&#39;&#39; at longer wavelengths. We present several new results regarding the model predictions, and show that X-ray to optical observations of GRB970228 and GRB970402 are naturally explained by the model: The scaling of flux with time and frequency agrees with mo

Robert L. Oldershaw

After two decades of efforts to identify the enigmatic dark matter that comprises the dominant form of matter in our galaxy, the mass range for viable candidates appears to have been reduced by more than 50 orders of magnitude. Positive results have thus far been confined to the range: 10-7 Mo to 1.0 Mo, with apparent clustering within the ranges 10-5 Mo to

Tom C. Braden, Robert D. MacPherson

We prove that the intersection homology Poincare&#39; polynomial P(X) of an affine toric variety X is bounded below by the product P(Y)P(X/Y), where Y is the closure of any orbit in X and X/Y is a slice transverse to the orbit. This proves a combinatorial conjecture of Kalai for rational polytopes.

Ganesh Devaraj, Robin G. Stuart

A general method for reducing tensor form factors, that appear in one-loop calculations in dimensional regularization, to scalar integrals is presented. The method is an extension of the reduction scheme introduced by Passarino and Veltman and is applicable in all regions of parameter space including those where kinematic Gram determinant vanishes. New relat

Jeongwon Ho, Won Tae Kim, Young-Jai Park, Hyeonjoon Shin

Entropy of the Kerr-Newman black hole is calculated via the brick wall method with maintaining careful attention to the contribution of superradiant scalar modes. It turns out that the nonsuperradinat and superradiant modes simultaneously contribute to the entropy with the same order in terms of the brick wall cutoff $ε$. In particular, the contribution of t

Shin&#39;ichirou Yoshida, Yoshiharu Eriguchi

Relativistic Cowling approximation in which all metric perturbations are omitted is applied to non-axisymmetric infinitesimal oscillations of uniformly rotating general relativistic polytropes. Frequencies of lower order f-modes which are important in analysis of secular instability driven by gravitational radiation are investigated and neutral points of the

Z. Chacko, B. Dutta, R. N. Mohapatra, S. Nandi

Recently, a proposal (by R.N.M. and S.N.) was made for a new class of gauge mediated supersymmetry breaking (GMSB) models where the standard model gauge group is embedded into the gauge group $SU(2)_L\times U(1)_{I_{3R}}\times U(1)_{B-L}$ (or $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$) at the supersymmetry breaking scale $Λ$. Supersymmetry breaking is transmit

Tomislav Kundic, Judith G. Cohen, Roger D. Blandford, Lori M. Lubin

The quadruple system PG 1115+080 is the second gravitational lens with a reported measurement of the Hubble constant. In addition to the primary lens, three nearby galaxies are believed to contribute significantly to the lensing potential. In this paper we report accurate redshifts for all four galaxies and show that they belong to a single group at z_d = 0.

Ron Lifshitz

Lattice color groups are introduced and used to study the partitioning of a periodically- or quasiperiodically-ordered set of points into N symmetry-related subsets. Applications range from magnetic structure to superlattice ordering in periodic and quasiperiodic crystals.

Toshifumi Futamase, Masahiro Tanaka

We have found a successful model of chaotic inflation with an inflaton coupled nonminimally with gravity. The nonminimal coupling constant $ξ$ runs with the evolution of the inflaton. The running nature of the coupling leads naturally to the situations where the coupling becomes small enough to have sufficient period of the inflation to resolve the cosmologi

S. S. Kamalov, E. Oset

We develop the formalism for coherent two pion photoproduction in nuclei and perform actual calculations of cross sections for $π^-π^+$ and $π^0π^0$ photoproduction on $^{12}C$. We find that due to the isospin symmetry the cross section for $π^0π^0$ production is very small and has a maximum when the pions propagate together. However, the kinematical region

P. Magierski, J. Skalski, J. Blocki

The excitation of a quantum gas of 112 independent fermions in the time-dependent potential well, periodically oscillating around the spherical shape, was followed over 10 oscillation cycles. Five different oscillation frequencies are considered for each of the five types of deformations: spheroidal and Legendre polynomial ripples: P_3, P_4, P_5 and P_6. The

G. Couture, M. Frank, H. König

We present a detailed and complete calculation of the doubly charged Higgsino contribution to the decays mu--> e photon and mu--> 3e and to the anomalous magnetic moment of the muon within the left-right supersymmetric model. We include the mixing of the scalar partners of the left and right handed leptons, and show that it leads to a strong enhancement of t

G. Couture, M. Frank, H. König

We present a detailed and complete calculation of the gluino and scalar quarks contribution to the flavour-changing top quark decay into a charm quark and a photon, gluon, or a Z boson within the minimal supersymmetric standard model including flavour changing gluino-quarks-scalar quarks couplings in the right-handed sector. We compare the results with the o

U. Cotti, J. L. Diaz-Cruz, J. J. Toscano

We study the production of the SM Higgs boson (H^0) at future e gamma colliders, through the reaction e gamma --> e H^0. The amplitude is evaluated using the non-linear R_ξgauge, which greatly simplifies the calculation. Complete analytical expressions for the amplitudes are presented, which include the contributions from 1-loop triangles &#34;gamma gamma^*

Wenji Deng, P. M. Hui

The partition function and specific heat of a system consisting of a finite number of bosons confined in an external potential are calculated in canonical ensemble. Using the grand partition function as the generating function of the partition function, an iterative scheme is established for the calculation of the partition function of system with an arbitra

Robert J. Nemiroff

In gravitational lensing, the concept of optical depth assumes the lens is dark. Several microlensing detections have now been made where the lens may be bright. Relations are developed between apparent and absolute optical depth in the regime of the apparent and absolute brightness of the lens. An apparent optical depth through bright lenses is always less

G. Fossati, A. Celotti, G. Ghisellini, L. Maraschi

We discuss alternative interpretations of the differences in the Spectral Energy Distributions (SEDs) of BL Lacs found in complete Radio or X-ray surveys. A large body of observations in different bands suggests that the SEDs of BL Lac objects appearing in X-ray surveys differ from those appearing in radio surveys mainly in having a (synchrotron) spectral cu

P. S. Udomprasert, G. B. Taylor, T. J. Pearson, D. H. Roberts

At a distance of 20 pc from the purported supermassive black hole powering quasars, temperatures and densities are inferred from optical observations to be ~10**4 K and ~10**4 cm**-3. Here we present Very Long Baseline Interferometry radio observations revealing organized magnetic fields on the parsec scale in the hot plasma surrounding the quasar OQ172 (144

K. S. Cheng, Z. G. Dai

We consider a model in which the soft gamma-ray repeaters (SGRs) result from young, magnetized strange stars with superconducting cores. As such a strange star spins down, the quantized vortex lines move outward and drag the magnetic field tubes because of the strong coupling between them. Since the terminations of the tubes interact with the stellar crust,

B. Shapiro, M. Shapiro, A. Vainshtein

In this paper we reduce the problem of counting the number of connected components in the intersection of two opposite open Schubert cells in the variety of real complete flags to a purely combinatorial question of counting the number of orbits of a certain intriguing group action in the space of upper triangular matrices with {0,1}-valued entries. The cruci

Maxim Markevitch

Comparison of the high resolution X-ray ROSAT HRI image of A2218 with the optical HST image shows several interesting correlations. The X-ray emission within a 1&#39; radius core is resolved into several components; the central dominant galaxy does not coincide with either of them or the emission centroid. The major X-ray peak is an elongated feature which c

A. Abd El-Hady, G. Valencia

We calculate the effect of new CP violating interactions parameterized by an anomalous $tbW$ coupling on CP-odd observables in B decays. We find that couplings consistent with current bounds induce observable effects in some CP asymmetries that will be measured in B-factories. The new effects are sufficiently large that they can actually test specific models

Yu. L. Dokshitzer, B. R. Webber

We estimate the effects of non-perturbative physics on the differential distributions of infrared- and collinear-safe $e^+e^-$ event shape variables, by extending the notion of an infrared-regular effective strong coupling, which accounts for the non-perturbative corrections to the mean values of several shape variables, to their distributions. This leads to

Marco D&#39;Attanasio, Tim R. Morris

In the large N limit, we show that the Local Potential Approximation to the flow equation for the Legendre effective action, is in effect no longer an approximation, but exact - in a sense, and under conditions, that we determine precisely. We explain why the same is not true for the Polchinski or Wilson flow equations and, by deriving an exact relation betw

Xiao-Jun Wang, Mu-Lin Yan

We examine low energy limit of $U(3)_L\times U(3)_R$ chiral theory of mesons through integrating out fields of vector and axial-vector mesons. The effective lagrangian for pseudoscalar mesons at $O(p^4)$ has been obtained, and five low energy coupling constants $L_i(i=1,2,3,9,10)$ have been revealed. They are in good agreement with the results of CHPT&#39;s

Gert-Martin Greuel, Christoph Lossen, Eugenii Shustin

We prove that there exists a>0 such that for any integer d>2 and any topological types S_1,...,S_n of plane curve singularities, satisfying $μ(S_1)+...+μ(S_n) \leq ad^2$, there exists a reduced irreducible plane curve of degree d with exactly n singular points of types S_1,...,S_n, respectively. This estimate is optimal with respect to the exponent of d. In

Siegfried Grossmann, Detlef Lohse, Achim Reeh

From Navier-Stokes turbulence numerical simulations we show that for the extended self similarity (ESS) method it is essential to take the third order structure function taken with the modulus and called $D_3^*(r)$, rather than the standard third order structure function $D_3(r)$ itself. If done so, we find ESS towards scales larger than roughly 10 eta, wher

Siegfried Grossmann, Detlef Lohse, Achim Reeh

Scaling exponents of the longitudinal and transversal velocity structure functions in numerical Navier-Stokes turbulence simulations with Taylor-Reynolds numbers up to $\rel = 110$ are determined by the extended self similarity method. We find significant differences in the degree of intermittency: For the sixth moments the scaling corrections to the classic

O. F. Dayi

Quantum Hall effect wave functions corresponding to the filling factors 1/2p+1, 2/2p+1, ..., 2p/2p+1, 1, are shown to form a basis of irreducible cyclic representation of the quantum algebra U_q(sl(2)) at q^{2p+1}=1. Thus, the wave functions Ψ_{P/Q} possessing filling factors P/Q<1 where Q is odd and P, Q are relatively prime integers are classified in terms

Masato Hisakado

The five-dimensional supersymmetric SU(N) gauge theory is studied in the framework of the relativistic Toda chain. This equation can be embedded in two-dimensional Toda lattice hierarchy. This system has the conjugate structure. This conjugate structure corresponds to the charge conjugation.

Hyeong-Chan Kim, Jae-Kwan Kim

We consider a radiation from a uniformly accelerating harmonic oscillator whose minimal coupling to the scalar field changes suddenly. The exact time evolutions of the quantum operators are given in terms of a classical solution of a forced harmonic oscillator. After the jumping of the coupling constant there occurs a fast absorption of energy into the oscil

N. Bralic, R. M. Cavalcanti, C. A. A. de Carvalho, P. Donatis

We study a relativistic two-dimensional free electron gas in the presence of a uniform external magnetic field and a random static scalar potential. We compute the expectation values of the charge density and the conductivity tensor, averaged over the random potential in first order perturbation theory. We discuss the effect of a zero vs. finite range correl

R. M. Cavalcanti

In [G. Garcia-Calderon, J. L. Mateos, and M. Moshinsky, Phys. Rev. Lett. 74, 337 (1995)], the time evolution of the quantum decay of a state initially located within an interaction region of finite range was investigated. In particular, it was shown that the survival and nonescape probabilities behave differently at very large times. The purpose of this Comm

E. Frenkel, N. Reshetikhin, M. A. Semenov-Tian-Shansky

We propose a q-difference version of the Drinfeld-Sokolov reduction scheme, which gives us q-deformations of the classical W-algebras by reduction from Poisson-Lie loop groups. We consider in detail the case of SL(2). The nontrivial consistency conditions fix the choice of the classical r-matrix defining the Poisson-Lie structure on the loop group LSL(2), an

K. Ueno, S. K. Sahu, K. C. Peng, W. S. Hou

Long BGO (Bismuth Germanate) and BSO (Bismuth Silicate) crystals coupled with silicon photodiodes have been used to detect minimum-ionizing particles(MIP). With a low noise amplifier customized for this purpose, the crystals can detect MIPs with an excellent signal-to-noise ratio. The NCE(Nuclear Counter Effect} is also clearly observed and measured. Effect

P. Chen, T. Ohgaki, A. Spitkovsky, T. Takahashi

The status and initial performance of a simulation program CAIN for interaction region of linear colliders is described. The program is developed to be applicable for e+e-, e-e-, e-gamma and gamma-gamma linear colliders. As an example of an application, simulation of a gamma-gamma collider option of NLC is reported.