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November 1996 arXiv papers — page 7

Showing 601700 of 1,462 papers

  1. R. B. Zhang, H. C. Lee

    Lickorish's method for constructing topological invariants of 3 - manifolds is generalized to the quantum supergroup setting. An invariant is obtained by applying this method to the Kauffman polynomial arising from the vector representation of Uq(osp(1|2)). A transparent proof is also given showing that this invariant is equivalent to the Uq(osp(1|2)) in

  2. Hans E. Plesser, Shigeru Tanaka

    The response of a noisy integrate-and-fire neuron with reset to periodic input is investigated. We numerically obtain the first-passage-time density of the pertaining Ornstein-Uhlenbeck process and show how the power spectral density of the resulting spike train can be determined via Fourier transform. The neuron's output clearly exhibits stochastic reso

  3. Jun Cao, Hui-fang Wu

    The contributions of helicity-flip matrix elements to the deuteron form factors are discussed in the light-cone frame. Normalized $A(Q^2)$, $B(Q^2)$, $G_Q(Q^2)$ and $T_{20}$ are obtained in a simple QCD-inspired model. We find that $G_{+-}^+$ plays an important role in $G_Q(Q^2)$. Our numerical results are consistent with the data in the intermediate energy

  4. Sergei A. Voloshin

    The effects of an interplay of radial expansion of the thermalized system created in a heavy ion collision and directed flow are discussed. It is shown that the study of azimuthal anisotropy of particle distribution as a function of rapidity and transverse momentum could reveal important information on both radial and directed flow.

  5. Avner Ash, Mark W. McConnell

    Let $\bold G$ be a reductive algebraic group defined over $\Q$, and let $Γ$ be an arithmetic subgroup of $\bold G(\Q)$. Let $X$ be the symmetric space for $\bold G(\R)$, and assume $X$ is contractible. Then the cohomology (mod torsion) of the space $X/Γ$ is the same as the cohomology of $Γ$. In turn, $X/Γ$ will have the same cohomology as $W/Γ$, if $W$ is a

  6. Dave Witte

    Let $\Ga$ be a connected, solvable linear algebraic group over a number field~$K$, let $S$ be a finite set of places of~$K$ that contains all the infinite places, and let $\theints$ be the ring of $S$-integers of~$K$. We define a certain closed subgroup~$\GOS$ of $\Ga_S = \prod_{v \in S} \Ga_{K_v}$ that contains $\Ga_{\theints}$, and prove that $\Ga_{\theint

  7. D. G. Barci, L. E. Oxman

    Asymptotic states in field theories containing non-local kinetic terms are analyzed using the canonical method, naturally defined in Minkowski space. We apply our results to study the asymptotic states of a non-local Maxwell-Chern-Simons theory coming from bosonization in 2+1 dimensions. We show that in this case the only asymptotic state of the theory, in t

  8. Jian-Ge Zhou, H. J. W. Mueller-Kirsten, J. -Q. Liang, F. Zimmerschied

    An M-brane and anti-M-brane scheme is proposed to study nonextremal 4D and 5D black holes. The improved nonextremal intersecting M-brane solutions proposed here, involve two sets of harmonic functions. The constraints among the pressures are found, and new features in the M-brane and anti-M-brane picture are demonstrated, which resolve the discrepancy in the

  9. Gaetano Fiore

    Can one represent quantum group covariant q-commuting "creators, annihilators" $A^+_i,A^j$ as operators acting on standard bosonic/fermionic Fock spaces? We briefly address this general problem and show that the answer is positive (at least) in some simplest cases.

  10. I. L. Egusquiza, M. A. Valle-Basagoiti

    A simple backreaction problem in quantum mechanics, the full quantum anharmonic oscillator, and quantum parametric resonance are studied using Renormalization Group techniques for global asymptotic analysis. In this short note this technique is adapted for the first time to operator problems.

  11. Shinji Hamamoto

    Izawa's gauge-fixing procedure based on BRS symmetry is applied twice to the massive tensor field theory of Fierz-Pauli type. It is shown the second application can remove massless singularities which remain after the first application. Massless limit of the theory is discussed.

  12. Joshua Erlich, Daniel Z. Freedman

    Two-loop contributions to the anomalous correlation function <J_mu(x)J_nu(y)J_rho(z)> of three chiral currents are calculated by a method based on the conformal properties of massless field theories. The method was previously applied to virtual photon diagrams in quantum electrodynamics, and it is extended here to diagrams with scalars and chiral spinors in

  13. Jogesh C. Pati

    The first part of this talk presents the general complexion of baryon and lepton number non-conservation that may arise in the context of quark-lepton unification. The second part presents the status of grand unification with and without supersymmetry and spells out the characteristic proton decay modes, which if seen, will clearly show supersymmetry. The ma

  14. G. Folberth, R. Rossmann, W. Schweiger

    We analyze the reactions gamma+p => M+B, with M B being either K+ Lambda, K+ Sigma0, or pi+ n, within perturbative QCD, allowing for diquarks as quasi-elementary constituents of baryons. The diquark-model parameters and the quark-diquark distribution amplitudes of the baryons are taken from previous investigations of electromagnetic baryon form factors and C

  15. Kyungsik Kang, Sin Kyu Kang, Jihn E. Kim, Pyungwon Ko

    Assuming three light neutrinos are Majorana particles, we propose mass matrix ansatz for the charged leptons and Majorana neutrinos with family symmetry $S_{3} $ broken into $S_{1}$ and $S_{2}$, respectively. Each matrix has three parameters, which are fixed by measured charged lepton masses, differences of squared neutrino masses relevant to the solar and t

  16. C. P. Burgess, D. Michaud

    We summarize a general formulation of particle propagation in fluctuating media, as applied to the description of neutrino propagation through the sun. It contains the familiar MSW effective hamiltonian, plus corrections which describe neutrino interactions with fluctuations in the medium. An estimate of the size of these corrections for a simple model of so

  17. Helmut Satz

    We first introduce the conceptual basis of critical behaviour in strongly interacting matter, with colour deconfinement as QCD analog of the insulator-conductor transition and chiral symmetry restoration as special case of the associated shift in the mass of the constituents. Next we summarize quark-gluon plasma formation in finite temperature lattice QCD. W

  18. Amruta Mishra, Hiranmaya Mishra

    We compute the effective potential for $ϕ^4$ theory with a squeezed coherent state type of construct for the ground state. The method essentially consists in optimising the basis at zero and finite temperatures. The gap equation becomes identical to resumming the infinite series of daisy and super daisy graphs while the effective potential includes multiloop

  19. G. Degrassi, P. Gambino, A. Sirlin

    The two-loop O(g^4 mt^2/mw^2) corrections are incorporated in the theoretical calculation of MW, sin^2 theta_MSbar(MZ), and sin^2 theta_eff, as functions of MH. The analysis is carried out in a previously proposed MSbar formulation and two novel on-shell resummation schemes. It is found that the inclusion of the new effects sharply decreases the scheme and r

  20. G. Barenboim, K. Huitu, J. Maalampi, M. Raidal

    Production of a single doubly charged Higgs boson $Delta^{--}$ in polarized $e^+e^-$ and $e^+γ$ collision modes of the linear collider have been investigated. The mass range of $Delta^{--}$ to be probed extends up to the collision energy. The diagonal lepton number violating Yukawa coupling $h_{ee}$ will be tested at least three orders of magnitude more stri

  21. Yu. S. Kalashnikova, A. V. Nefediev

    The system of two relativistic particles with einbein fields is quantized as a constrained system.A method of the introduction of the Newton--Wigner collective coordinate is discussed in presence of different gauge fixing conditions. Some arguments are involved in the favour of Lorents covariant gauge fixing conditions.

  22. L. B. Okun

    In the framework of a model, in which a single leptonic photon $γ_l$ has the same coupling to the doublets $μν_μ$ and $\barτ\barν_τ$, there is no cosmological bound on the strength of this coupling.

  23. N. Hammon, O. Teryaev, A. Schäfer

    We calculated the single spin asymmetries for the reaction $P+P(\uparrow)\rightarrow l \overline{l}+X$ in the framework of twist-3 QCD for HERA energies. The necessary imaginary phase is produced by the on-shell contribution of the quark propagator, while the long distance part is analogous to that providing the direct photon asymmetry calculated by J. Qiu a

  24. Paolo Gambino

    The radiative corrections involved in the precise determination of the electroweak mixing angle measured at the Z-peak are reviewed in detail, with particular emphasis on the new calculation of two-loop heavy top effects. This example serves as a brief pedagogical introduction to the problems and techniques of higher order electroweak calculations.

  25. David London

    I review several topics involving CP violation with heavy hadrons. In particular, I discuss (i) Hyperons: CP violation in the decay $Λ^0 \to p π^-$, (ii) Charm: indirect CP violation in the D^0 system, both within and beyond the SM, and (iii) Beauty: indirect CP violation in the neutral B-meson system beyond the SM. Talk presented at the 2nd International Co

  26. L. Clavelli, P. W. Coulter, L. R. Surguladze

    We deduce the gluino contribution to the three-loop QCD βfunction within the minimal supersymmetric Standard Model (MSSM) from its standard QCD expression. The result is a first step in the computation of the full MSSM three-loop βfunction. In addition, in the case of a light gluino it provides the strong three-loop SUSY correction to the extrapolation of th

  27. F. Halzen

    Initial deployment of optical modules near 1 and 2 kilometer depth indicate that deep polar ice is the most transparent known natural solid. Experience with early data has revealed that a detector, conceived to measure muons tracks, can also measure energy of high energy neutrinos as well as bursts of MeV neutrinos, e.g. produced by supernovae and gamma ray

  28. A. H. Castro Neto

    We propose a model for the physics of stripes in antiferromagnets in which the stripes are described by Luttinger liquids hybridized with antiferromagnetic domains. Using bosonization techniques we study the model in the limit where the magnetic correlation length is larger than the inter-stripe distance and propose an explanation for the commensurate-incomm

  29. Jeongnim Kim, John W. Wilkins, Furrukh S. Khan, Andrew Canning

    We perform total energy calculations based on the tight-binding Hamiltonian scheme (i) to study the structural properties and energetics of the extended {311} defects depending upon their dimensions and interstitial concentrations and (ii) to find possible mechanisms of interstitial capture by and release from the {311} defects. The generalized orbital-based

  30. C. P. Adams, T. E. Mason, S. A. M. Mentink, E. Fawcett

    We have used resistivity measurements to study the magnetic phase diagram of the itinerant antiferromagnet FeGe_2 in the temperature range from 0.3->300 K in magnetic fields up to 16 T. In contrast to theoretical predictions, the incommensurate spin density wave phase is found to be stable at least up to 16 T, with an estimated critical field μ_0H_c of ~ 30

  31. Petr Král

    Gradient expansions in quantum transport equations of a Kadanoff-Baym form have been reexamined. We have realized that in a consistent approach the expansion should be performed also inside of the self-energy in the scattering integrals of these equations. In the first perturbation order this internal expansion gives new correction terms to the generalized B

  32. Augusto Gonzalez

    We present analytic estimates for the energy levels of N electrons (N = 2 - 5) in a two-dimensional parabolic quantum dot. A magnetic field is applied perpendicularly to the confinement plane. The relevant scaled energy is shown to be a smooth function of the parameter β=(effective Rydberg/effective dot energy)^{1/6}. Two-point Pade approximants are obtained

  33. M. J. M. de Jong, C. W. J. Beenakker

    This is a review of shot noise, the time-dependent fluctuations in the electrical current due to the discreteness of the electron charge, in small conductors. The shot-noise power can be smaller than that of a Poisson process as a result of correlations in the electron transmission imposed by the Pauli principle. This suppression takes on simple universal va

  34. D. Foerster, F. Triozon

    We study the O(N) quantum Heisenberg antiferromagnet using a parametrisation in terms of real fermions. The N->infinity limit of the model is controlled by a saddle point that is infinitely degenerate in many cases and which represents singlet states on dimers that cover the lattice. Our results are similar to results reported previously on an SU(N) generali

  35. Yi-Kuo Yu

    The chiral surface electrons in the bulk quantum Hall effect probably form the first extended system in which conductance fluctuations can be calculated non-perturbatively in the presence of disorder. By use of the Kubo formula with appropriate boundary conditions, we calculate exactly the variance of conductance with non-perturbative methods. We find that t

  36. Safi R. Bahcall

    We introduce a random matrix ensemble for bulk type-II superconductors in the mixed state and determine the single-particle excitation spectrum using random matrix theory. The results are compared with planar tunnel junction experiments in PbBi thin films. More low energy states appear than in the Abrikosov-Gor&#39;kov-Maki or Ginzburg-Landau descriptions, c

  37. Yong-Jihn Kim

    In the electron-phonon model, the influence of nonmagnetic impurities on the transition temperature of superconductors is revisited. Anderson&#39;s pairing condition between time-reversed eigenstate pairs is derived from the physical constraint of the Anomalous Green&#39;s function. After this pairing condition is incorporated into the self-consistency equat

  38. Steven H. Simon, Patrick A. Lee

    In finite magnetic field H, the excitation spectrum of the low energy quasiparticles in a 2 dimensional d-wave superconductor exhibits a scaling with respect to $H^{1/2}$. This property can be used to calculate scaling relations for various physical quantities at low temperature T. As examples, we make predictions for the scaling behavior of the finite magne

  39. Harel Primack, Holger Schanz, Uzy Smilansky, Iddo Ussishkin

    The semiclassical description of billiard spectra is extended to include the diffractive contributions from orbits which are nearly tangent to a concave part of the boundary. The leading correction for an unstable isolated orbit is of the same order as the standard Gutzwiller expression itself. The importance of the diffraction corrections is further emphasi

  40. B. T. Draine, Joseph C. Weingartner

    Radiative torques on irregular dust grains, in addition to producing superthermal rotation, play a direct dynamical role in the alignment of interstellar dust with the local magnetic field. The equations governing the orientation of spinning, precessing grains are derived; H_2 formation torques and paramagnetic dissipation are included in the dynamics. Stati

  41. Neta A. Bahcall

    Rich clusters of galaxies are the most massive virialized systems known. Even though they contain only a small fraction of all galaxies, rich clusters provide a powerful tool for the study of galaxy formation, dark matter, large-scale structure, and cosmology. Superclusters, the largest known systems of galaxies, extend to (approx) 100h^{-1} Mpc in size and

  42. Winfried Zimdahl, Diego Pavón, Roy Maartens

    The reheating process in inflationary universe models is considered as an out-of-equilibrium mixture of two interacting and reacting fluids, and studied within the framework of causal, irreversible thermodynamics. The evolution of the temperature and the decay rate as determined by causal thermodynamics are estimated at different stages of the process. A sim

  43. Frank C. van den Bosch, Walter Jaffe

    We discuss photometric and spectroscopic data of the E/S0 galaxy NGC 4342, obtained with the Hubble Space Telescope (HST). This galaxy harbors, in addition to its outer disk, a very small, stellar disk in its nucleus. Jeans-modeling suggests the presence of a 3-6$\times 10^8 \Msun$ black hole (BH) in the nucleus. This galaxy therefore deviates significantly

  44. Frank C. van den Bosch

    The deprojection of the surface brightness of axisymmetric galaxies is indeterminate unless the galaxy is seen edge-on. In practice, this problem is often circumvented by making ad hoc assumptions about the density distribution. However, one can redistribute the density and still project to the same surface brightness. This is similar to adding so-called kon

  45. Antoinette Songaila, E. Joseph Wampler, Lennox L. Cowie

    The amount of deuterium relative to hydrogen (D/H) in clouds with close to primordial abundance seen at high redshift in the spectra of distant quasars currently provides the best estimate of the baryonic density of the Universe. The first measurements have yielded discrepant values of D/H both high [around 2 x 10^(-4)] and an order of magnitude lower. The l

  46. F. Acquistapace, C. Andradas, F. Broglia

    In this paper we study the problem of deciding whether two disjoint semialgebraic sets of an algebraic variety over R are separable by a polynomial. For that we isolate a dense subfamily of Spaces of Orderings, named Geometric, which suffice to test separation and that reduce the problem to the study of the behaviour of the semialgebraic sets in their bounda

  47. Pierre Parent

    In this paper we give a detailed proof of a result we announced a year ago. This result is an effective version of the theorem of Mazur-Kamienny-Merel concerning uniform bounds for rational torsion points on elliptic curves over number fields.

  48. Klaus Behrndt, Thomas Mohaupt

    In this paper we discuss the M-brane description for a N=2 black hole. This solution is a result of the compactification of M-5-brane configurations over a Calabi-Yau threefold with arbitrary intersection numbers $C_{ABC}$. In analogy to the D-brane description where one counts open string states we count here open 2-branes which end on the M-5-brane.

  49. JINR Neutrino Detector Collaboration, L. S. Barabash et al

    The isoscalar structure functions xF_3 and F_2 are measured as functions of x averaged over all Q^2 permissible for the range 6 to 28 GeV of incident (anti)neutrino energy. With the measured values of xF_3, the value of the Gross-Llewellyn Smith sum rule is found to be $\int_{0}^{1}{F_3 dx} = 2.13\pm0.38 (stat)\pm 0.26 (syst)$. The QCD analysis of xF_3 provi

  50. Paul S. Aspinwall

    The primary purpose of these lecture notes is to explore the moduli space of type IIA, type IIB, and heterotic string compactified on a K3 surface. The main tool which is invoked is that of string duality. K3 surfaces provide a fascinating arena for string compactification as they are not trivial spaces but are sufficiently simple for one to be able to analy

  51. Laurent Baulieu, Michael B. Green, Eliezer Rabinovici

    String theories with (N,N&#39;) local world-sheet supersymmetries are related to each other by marginal deformations. This connects N=1 and N=0 theories in which the target-spaces are interpreted as space-times, N=2 theories in which the target spaces can be interpreted as world-volumes, and theories with $N\ge 3$, in which the central charge vanishes -- the

  52. A. Ghinculov, T. Binoth

    Higher loop calculations in the Higgs sector of the standard model at the Higgs mass scale have shown that perturbation theory diverges very badly at about 1 TeV in the on-shell renormalization scheme. The prediction of the position of the Higgs pole in the complex s-plane becomes unreliable. We show that in the pole renormalization scheme this appears to ha

  53. Vladimir Lin, Mikhail Zaidenberg

    A Riemannian manifold resp. a complex space $X$ is called Liouville if it carries no nonconstant bounded harmonic resp. holomorphic functions. It is called Carathéodory, or Carathéodory hyperbolic, if bounded harmonic resp. holomorphic functions separate the points of $X$. The problems which we discuss in this paper arise from the following question: When a

  54. I. V. Lavrinenko, H. Lu, C. N. Pope

    In the usual procedure for toroidal Kaluza-Klein reduction, all the higher-dimensional fields are taken to be independent of the coordinates on the internal space. It has recently been observed that a generalisation of this procedure is possible, which gives rise to lower-dimensional ``massive&#39;&#39; supergravities. The generalised reduction involves allo

  55. Robert C. Myers, Vipul Periwal

    A new form of the Wilson renormalization group equation is derived, in which the flow equations are, up to linear terms, proportional to a gradient flow. A set of coördinates is found in which the flow of marginal, low-energy, couplings takes a gradient form, if relevant couplings are tuned to vanish.

  56. K. G. Chetyrkin, R. Harlander, J. H. Kuehn, M. Steinhauser

    We discuss the calculation of two-point three-loop functions with an arbitrary number of massive propagators and one large external momentum. The relevant subdiagrams are generated automatically. The resulting massless two-point integrals and massive tadpoles are transformed on-line to FORM-expressions ready to be used by existing FORM packages which calcula

  57. Max Tegmark

    The next generation of CMB experiments can measure cosmological parameters with unprecedented accuracy - in principle. To achieve this in practice when faced with such gigantic data sets, elaborate data analysis methods are needed to make it computationally feasible. An important step in the data pipeline is to make a map, which typically reduces the size of

  58. Peter Bantay

    The conjecture of Fuchs, Schellekens and Schweigert on the relation of mapping class group representations and fixed point resolution in simple current extensions is investigated, and a cohomological interpretation of the untwisted stabilizer is given.

  59. Z. Bern, L. Dixon, D. C. Dunbar, D. A. Kosower

    We conjecture a simple relationship between the one-loop maximally helicity violating gluon amplitudes of ordinary QCD (all helicities identical) and those of N=4 supersymmetric Yang-Mills (all but two helicities identical). Because the amplitudes in self-dual Yang Mills have been shown to be the same as the maximally helicity violating ones in QCD, this con

  60. Marina Hruska, Wai-Yee Keung, Uday Sukhatme

    We study the accuracy of several alternative semiclassical methods by computing analytically the energy levels for many large classes of exactly solvable shape invariant potentials. For these potentials, the ground state energies computed via the WKB method typically deviate from the exact results by about 10%, a recently suggested modification using noninte

  61. Denis V. Juriev

    This note being devoted to some aspects of the inverse problem of representation theory explicates the links between researches on the Sklyanin algebras and the author&#39;s (based on the noncommutative geometry) approach to the setting free of hidden symmetries in terms of &#34;the quantization of constants&#34;. Namely, the Racah-Wigner algebra for the Skl

  62. Sergei Khoroshkin, Vadim Schechtman

    A braided tensor category $FM_κ$ of `factorizable D-modules&#39; over configuration spaces is introduced, analogous to the category $FS_q$ of factorizable sheaves from q-alg/9604001. This category is equivalent to the category of finite dimensional representations of a complex semisimple Lie algebra $\frak{g}$, with the Drinfeld&#39;s Knizhnik-Zamolodchikov

  63. G. Q. Li, C. M. Ko, G. E. Brown, H. Sorge

    Dilepton production in proton- and nucleus-induced reactions is studied in relativistic transport model using initial conditions determined by the string dynamics from RQMD. It is found that both the CERES and HELIOS-3 data for dilepton spectra in proton-nucleus reactions can be well described by the `conventional&#39; mechanism of Dalitz decay and direct ve

  64. J. Gegenberg

    A three dimensional supergravity theory which generalizes the super IG theory of Witten and resembles the model discussed recently by Mann and Papadopoulos is displayed. The partition function is computed, and is shown to be a three-manifold invariant generalizing the Casson invariant.

  65. I. Brevik, D. M. Gitman, S. D. Odintsov

    The formalism, which permits to study the phase structure of gauged NJL-model for arbitrary external fields, is developed. The effective potential in the gauged NJL model in the weak magnetic field is found. It is shown that in fixed gauge coupling case the weak magnetic field doesn&#39;t influence chiral symmetry breaking condition. The analogy with the sit

  66. Michael Gutperle

    Boundary states for D-branes are constructed using the light cone gauge. The D-brane breaks half the spacetime supersymmetry giving rise to fermionic zero modes living on the brane. The nonlinear realization of the broken supersymmetry on the open string degrees of freedom is analysed and the influence of boundary terms coming from closed string vertex opera

  67. Michael Mueger

    We demonstrate the role of Drinfeld&#39;s quantum double D(G) as a spontaneously broken hidden symmetry in a large class of massive quantum field theories in 1+1 dimensions with compact symmetry group G. Our considerations are independent of exact integrability. The main technical ingredient is an assumption concerning the statistical independence of fields

  68. M. Kreuzer, M. Nikbakht-Tehrani

    Using the simple current method we study a class of $(0,2)$ SCFTs which we conjecture to be equivalent to (0,2) sigma models constructed in the framework of gauged linear sigma models.

  69. A. N. Mitra

    Using the method of Green&#39;s functions within the framework of a Bethe-Salpeter formalism characterized by a pairwise $qq$ interaction with a 3D support to its kernel (expressed in a Lorentz-covariant manner), the 4D BS wave function for a system of three identical relativistic spinless quarks is reconstructed from the corresponding 3D form which satisfie

  70. Holger Bech Nielsen, Hans Henrik Rugh, Svend Erik Rugh

    We discuss space-time chaos and scaling properties for classical non-Abelian gauge fields discretized on a spatial lattice. We emphasize that there is a ``no go&#39;&#39; for simulating the original continuum classical gauge fields over a long time span since there is a never ending dynamical cascading towards the ultraviolet. We note that the temporal chaot

  71. Clemens A. Heusch, Peter Minkowski

    Recent considerations by these authors pointed out the attractive features which a search for the exchange of heavy Majorana neutrinos could have for solving the mass and the lepton number puzzles for all neutrinos, in TeV-level electron-electron scattering. In the present note, we show that, contrary to subsequently published arguments, non-observation of n

  72. T. K. Gaisser

    Several models of minimum-bias hadronic interactions at ultra-high energy that have been used for calculations of air showers share essential common features. In this talk I review these common elements and discuss some consequences. I concentrate on properties of hadron-nucleus interactions, and I use mean depth of shower maximum as a function of primary en

  73. Cai-Dian Lu, Da-Xin Zhang

    The effective Hamiltonian for the R-parity violating couplings induced nonleptonic decay $B^-\to K^-K^0$ is calculated including leading log QCD corrections running from $m_{\tilde q}$, the mass of the up-type squark, to $m_b$. Experimental upper limit of this decay is used to give the bound on the R-parity violating couplings $λ&#39;&#39;$.

  74. S. V. Goloskokov

    We analyse the diffractive $Q \bar Q$ production and final jet kinematics in polarized deep-inelastic lp scattering at $\sqrt{s}=20 GeV$. We show that this reaction can be used in the new spectrometer of the COMPASS Collaboration at CERN to study the quark-pomeron coupling structure.

  75. N. Nakajima, M. Biyajima, N. Suzuki

    We investigate the KNO scaling function of the modified negative binomial distribution (MNBD), because this MNBD can explain the oscillating behaviors of the cumulant moment observed in $e^+e^-$ annihilations and in hadronic collisions. By using a straightforward method and the Poisson transform we derive the KNO scaling function from the MNBD. The KNO form

  76. Philip G. Ratcliffe

    The plenary presentations of the conference are summarised, highlighting some aspects that were of particular interest and attempting to link a few of the topics covered. Particular emphasis is placed on the problem of deep-inelastic scattering and questions still to be answered with regard to the distribution functions, strange-quark and gluon contributions

  77. G. Barenboim, J. Bernabeu, J. Prades, M. Raidal

    We update the constraints on the right-handed $W_R$ gauge boson mass, mixing angle $ζ$ with the left-handed $W_L$ gauge boson, and other parameters in general left-right symmetric models with different mechanisms of CP violation. Constraints mostly independent of any assumption on the quark sector are obtained from a re-analysis of muon decay data. Estimates

  78. Gerhard Ecker

    A survey is made of semileptonic and nonleptonic kaon decays in the framework of chiral perturbation theory. The emphasis is on what has been done rather than how it was done. The theoretical predictions are compared with available experimental results.

  79. G. L. Kotkin, V. G. Serbo

    The elastic light-light scattering below the threshold of the $e^+e^-$ pair production leads to a variation in polarization of hard $γ$-quanta traversing without loss a region where the laser light is focused. Equations are obtained which determine the variation of Stokes parameters of $γ$-quanta in this case, and their solutions are given. It is pointed out

  80. NuTeV Collaboration, A. Romosan

    Limits on $ν_μ(\overlineν_μ) \to ν_e (\overlineν_e)$ oscillations based on a statistical separation of $ν_e N$ charged current interactions in the CCFR detector at Fermilab are presented. $ν_e$ interactions are identified by the difference in the longitudinal shower energy deposition pattern of $ν_e N \rightarrow eX$ versus $ν_μN \to ν_μX$ interactions. Neut

  81. SLD Collaboration, K. Abe, K. Abe, I. Abt et al

    We present a new measurement of the left-right cross section asymmetry (ALR) for Z boson production by e+e- collisions. The measurement was performed at a center-of-mass energy of 91.28 GeV with the SLD detector at the SLAC Linear Collider (SLC). The luminosity-weighted average polarization of the SLC electron beam was (77.23+-0.52)%. Using a sample of 93,64

  82. V. Sedykh, B. Shapiro

    For a convex curve in an even-dimensional affine space we introduce a series of convex domains (called Young hulls), describe their structure and give a formulas fo the volume of the biggest of these domains. This paper is an attempt to generalize the classical isoperimetric inequality for the volume of the convex hull of a space curve due to I.Schoenberg.

  83. P. B. A. Lecomte, V. Yu. Ovsienko

    We define the unique (up to normalization) symbol map from the space of linear differential operators on $R^n$ to the space of polynomial on fibers functions on $T^* R^n$, equivariant with respect to the Lie algebra of projective transformations $sl_{n+1}\subset\Vect(R^n)$. We apply the constructed $sl_{n+1}$-invariant symbol to studying of the natural one-p

  84. E. Gurevich, B. Shapiro

    We study orbital magnetism of a degenerate electron gas in a number of two-dimensional integrable systems, within linear response theory. There are three relevant energy scales: typical level spacing, the energy related to the inverse time of flight across the system, and the Fermi energy. Correspondingly, there are three distinct temperature regimes: micros

  85. A. Schroeder, G. Aeppli, T. E. Mason, E. Bucher

    Cold neutron spectroscopy was performed on CeNi_{1-x}Cu_xSn to investigate how the magnetic gap in the &#39;Kondo insulator&#39; CeNiSn is destroyed by temperature (T), chemical substitution (x), and external magnetic field. Upon doping, the spin gap collapses and magnetic Bragg peaks occur initially (x = 0.13) at the commensurate wave vectors Q = (0,m/2,l)

  86. G. Giugliarelli, A. L. Stella

    A $2D$ model describing depinning of an interface from a rough, self-affine substrate, is studied by transfer matrix methods. The phase diagram is determined for several values of the roughness exponent, $ζ_S$, of the attractive wall. For all $ζ_S>0$ the following scenario is observed. In first place, in contrast to the case of a flat wall ($ζ_S=0$), for wal

  87. B. Lopez, W. Kinzel

    A perceptron with N random weights can store of the order of N patterns by removing a fraction of the weights without changing their strengths. The critical storage capacity as a function of the concentration of the remaining bonds for random outputs and for outputs given by a teacher perceptron is calculated. A simple Hebb-like dilution algorithm is present

  88. Geunbae Lee, Jong-Hyeok Lee, Sangeok Kim

    This paper presents a HMM-based speech recognition engine and its integration into direct manipulation interfaces for Korean document editor. Speech recognition can reduce typical tedious and repetitive actions which are inevitable in standard GUIs (graphic user interfaces). Our system consists of general speech recognition engine called ABrain {Auditory Bra

  89. Marko Robnik

    We generalize the formalism and the techniques of the supersymmetric (susy) quantum mechanics to the cases where the superpotential is generated/defined by higher excited eigenstates. The generalization is technically almost straightforward but physically quite nontrivial since it yields an infinity of new classes of susy-partner potentials, whose spectra ar

  90. Christopher L. Taylor

    I study the VLA HI survey of HII galaxies by Taylor et al. (1995, ApJS, 99, 427; 1996, ApJS, 102, 189) and the VLA HI survey of low surface brightness (LSB) dwarf galaxies by Taylor et al. (1996, ApJS, in press) to investigate the role of galaxy interactions in triggering the bursts of massive star formation seen in HII galaxies. I find that the companion ra

  91. Duncan A. Forbes

    The HST&#39;s WFPC2 has several advantages over ground--based observations for the study of globular cluster luminosity functions (GCLFs) and distance determination. Here we present WFPC2 data on the globular clusters associated with NGC 5846. This giant elliptical is the dominant galaxy in a small, compact group located ~ 13 Mpc beyond the Virgo cluster. We

  92. Duncan A. Forbes

    The turnover, or peak, magnitude in a galaxy&#39;s globular cluster luminosity function (GCLF) may provide a standard candle for an independent distance estimator. Here we examine the GCLF of the giant elliptical NGC 4365 using photometry of ~ 350 globular clusters from the HST&#39;s WFPC2. The WFPC2 data have several advantages over equivalent ground--based

  93. Duncan A. Forbes

    The membership of some galaxies in the nearby (d ~ 12 Mpc) Coma I cloud is uncertain. Here we present globular cluster luminosity functions (GCLFs) from the HST for two bright ellipticals which may belong to this group. After fitting the GCLF, we find a turnover magnitude of m_V^0 = 23.23 +/- 0.11 for NGC 4278 and m_V^0 = 23.07 +/- 0.13 for NGC 4494. Our lim

  94. G. Mignola

    We investigate the possibility that the antiproton-to-proton flux ratio which is measured in cosmic rays may be generated by neutralino-neutralino annihilation in the galactic halo. We study the most general compositions for the relic neutralinos. We compare our results with the present experimental sensitivity and find that the theoretical predictions are a

  95. A. Bottino

    We examine the main properties of relic neutralinos in the context of the Minimal Supersymmetric extension of the Standard Model. We present a whole set of results obtained for the relic abundance and for detection rates with a model constrained according to the latest accelerator data. Predicted detection rates for relic neutralinos are compared to the pres

  96. Andrew Gould

    Four ongoing microlensing experiments have produced important new results but also big puzzles, the major one being that the expected classes of lenses cannot account for the observed distribution of time scales. I discuss future experiments that could resolve these puzzles. By far the most important would be to launch a parallax satellite into solar orbit.

  97. Tsevi Mazeh, Yuval Krymolowski, Gady Rosenfeld

    We consider the high eccentricity, 0.66, of the newly discovered planet around 16 Cyg B, using the fact that the parent star is part of a wide binary. We show that the high eccentricity of the planet could be the result of tidal forces exerted on 16 Cyg B and its planet by 16 Cyg A, the distant companion in the system. By following stellar triple systems wit

  98. Joachim Wambsganss

    The current searches for microlensing events towards the galactic bulge can be used to detect planets around the lensing stars. Their effect is a short-term modulation on the smooth lightcurve produced by the main lensing star. Current and planned experiments should be sensitive enough to discover planets ranging from Jupiter mass down to Earth mass. For a s

  99. W. Steffen

    Observational signatures of helical jets can be found in some X-ray binaries (XRB), planetary nebulae, Herbig-Haro objects and in jets of active galactic nuclei (AGN). For the prototypical XRB SS433 a kinematic model of precessing jets has been applied very successfully and yielded a determination of its distance which is independent of conventional methods.

  100. M. Gambera, A. Pagliaro

    We solve numerically the equations of motion for the collapse of a shell of baryonic matter, made of galaxies and substructure of $ 10^{6} M_{\odot} ÷10^{9} M_{\odot}$, taking into account the dynamical friction and the parameters on which it depends: the peaks&#39; height $ν_{c}$, the number of peaks inside a protocluster $N_{tot}$ multiplied by the correla