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October 2002 arXiv papers — page 4

Showing 301–400 of 3,443 papers

  1. H. Breitzke, I. Eremin, D. Manske, E. V. Antipov

    We report pure zero field nuclear magnetic resonance (NQR) measurements on the optimally doped three layer high-$ T_{c} $-compounds HgBaCaCuO and HgBaCaCuO(F) with $T_c$ 134 K. Above $ T_{c}$ two Cu NQR line pairs are observed in the spectra corresponding to the two inequivalent Cu lattice sites. Below $ T_{c}$ the Cu NQR spectra show additional lines leadin

  2. Maxim Olshanii, Vanja Dunjko

    We derive exact closed form expressions for the first few terms of the short-distance Taylor expansion of the one-body correlation function of the Lieb-Liniger gas. As an intermediate result we obtain the high-p asymptotics of the momentum distribution of both free and harmonically trapped atoms and show that it obeys a universal 1/p^4 law for_all_ values of

  3. R. Enberg, G. Ingelman, N. Timneanu

    Models for soft color interactions have been successful in describing and predicting diffractive hard scattering processes in ep collisions at DESY HERA and ppbar at the Fermilab Tevatron. Here we present new comparisons of the model to recent diffractive dijet data, also showing good agreement. The topical issue of diffractive Higgs production at the Tevatr

  4. Ehud Nakar, Tsvi Piran, Jonathan Granot

    We present general analytic expressions for GRB afterglow light curves arising from a variable external density profile and/or a variable energy in the blast wave. The former could arise from a clumpy ISM or a variable stellar wind; The latter could arise from refreshed shocks or from an angular dependent jet structure (patchy shell). Both scenarios would le

  5. A. Gorsky

    We discuss the restrictions imposed by the Konishi anomaly on the matrix model approach to the calculation of the effective superpotentials in N=1 SUSY gauge theories with different matter content. It is shown that they correspond to the anomaly deformed Virasoro $L_0$ constraints .

  6. Yan V. Fyodorov, Gernot Akemann

    We show that the expression for the supersymmetric partition function of the chiral Unitary Ensemble conjectured recently by Splittorff and Verbaarschot [Phys. Rev. Lett. v. 90, 041601 (2003)] follows from the general expression derived recently by Fyodorov and Strahov [ J. Phys. A: Math.Gen.} {\bf 36}(2003) 3203] .

  7. Alessandro Melchiorri, Carolina Odman

    One of the major predictions of inflation is the existence of a stochastic background of cosmological gravitational waves (GW). These gravitational waves can induce significant temperature anisotropies in the Cosmic Microwave Background (CMB) on the angular scales recently probed by the Archeops experiment. Here, we perform a combined analysis of Archeops to

  8. R. Clarkson, L. Fatibene, R. B. Mann

    We consider the thermodynamic properties of $(d+1)$-dimensional spacetimes with NUT charges. Such spacetimes are asymptotically locally anti de Sitter (or flat), with non-trivial topology in their spatial sections, and can have fixed point sets of the Euclidean time symmetry that are either $(d-1)$-dimensional (called "bolts") or of lower dimensional

  9. Inyong Cho

    We study five dimensional brane physics induced by an O(2) texture formed in one extra dimension. The model contains two 3-branes of nonzero tension, and the extra dimension is compact. The symmetry-breaking scale of the texture controls the particle hierarchy between the two branes. The TeV-scale particles are confined to the negative-tension brane where th

  10. V. S. Fadin, D. Yu. Ivanov, M. I. Kotsky

    The definition of the virtual photon impact factor involves the integration of the s-channel discontinuity of the photon-Reggeon scattering amplitude over the right cut. It permits to formulate a new approach for the calculation of the impact factor based on analytical properties of the amplitude in question. In the next-to-leading order it may give a possib

  11. Franz Lehner

    Fock space constructions give rise to natural exchangeable families and are thus well suited for cumulant calculations. In this paper we develop some general formulas and compute cumulants for generalized Toeplitz operators, notably for q-Fock spaces, previously considered by M. Anshelevich and A. Nica, and Fock spaces for characters of the infinite symmetri

  12. Franz Lehner

    Cumulants linearize convolution of measures. We use a formula of Good to define noncommutative cumulants in a very general setting.It turns out that the essential property needed is exchangeability of random variables. Roughly speaking the formula says that cumulants are moments of a certain ``discrete Fourier transform'' of a random variable. This p

  13. Alexandre F. da Fonseca, C. P. Malta, Marcus A. M. de Aguiar

    We study the three-dimensional static configurations of nonhomogeneous Kirchhoff filaments with periodically varying Young's modulus. This type of variation may occur in long tandemly repeated sequences of DNA. We analyse the effects of the Young's modulus frequence and amplitude of oscillation in the stroboscopic maps, and in the regular (non chaoti

  14. Xavier Bekaert, Nicolas Boulanger, Marc Henneaux

    The consistent, local, smooth deformations of the dual formulation of linearized gravity involving a tensor field in the exotic representation of the Lorentz group with Young symmetry type (D-3,1) (one column of length D-3 and one column of length 1) are systematically investigated. The rigidity of the Abelian gauge algebra is first established. We next prov

  15. Dirk P. Hansen, Janis R. Mohr, Andreas Hemmerich

    Metastable calcium atoms, produced in a magneto-optic trap (MOT) operating within the singlet system, are continuously loaded into a magnetic trap formed by the magnetic quadrupole field of the MOT. At MOT temperatures of 3 mK and 240 ms loading time we observe 1.1 x 10^8 magnetically trapped 3P2 atoms at densities of 2.4 x 10^8 cm^-3 and temperatures of 0.6

  16. G. M. Kavoulakis

    Considering an effectively attractive quasi-one-dimensional Bose-Einstein condensate of atoms confined in a toroidal trap, we find that the system undergoes a phase transition from a uniform to a localized state, as the magnitude of the coupling constant increases. Both the mean-field approximation, as well as a diagonalization scheme are used to attack the

  17. F. K. Sutaria, A. Ray, P. Chandra

    Combined X-ray (0.3 -10 keV) and Radio (0.61 and 1.42 GHz) observations of the type Ic SN 2002ap are used here, to determine the origins of the prompt X-ray and Radio emission from this source.Our analysis of the XMM-Newton observations suggests that the prompt X-ray emission originates from inverse Compton scattering of photospheric thermal emission by ener

  18. Swarnali Bandopadhyay, P. Singha Deo

    Elastic scattering in a quantum wire has several novel features not seen in 1D, 2D or 3D. In this work we consider a single channel quantum wire as its application is inevitable in making devices based on quantum interference effects. We consider a point defect or a single delta function impurity in such a wire and show how some of these novel features affec

  19. Ali Kaya

    We construct open cosmic string solutions in Schwarzschild black hole and non-dilatonic black p-brane backgrounds. These strings can be thought to stretch between two D-branes or between a D-brane and the horizon in curved space-time. We study small fluctuations around these solutions and discuss their basic properties.

  20. Yuji Koike

    Cross section formulas for the single spin asymmetry in $p^\uparrow p\to π(\ell_T)X$ and $e p^\uparrow \to π(\ell_T)X$ are derived and its characteristic features are discussed.

  21. Young Deuk Kim

    Let $H^n$ be the hyperbolic n-space with $n\geq 2$. Suppose that $Γ<Isom H^n$ is a discrete, torsion free subgroup and $a$ is a point in the domain of discontinuity $Ω(Γ)$. Let $p$ be the projection map from $H^n$ to the quotient manifold $M=H^n/Γ$. In this paper we prove that there exists an open neighborhood $U$ of $a$ in $H^n\cupΩ(Γ)$ such that $p$ is an

  22. Nicolas Arnaud, Matteo Barsuglia, Marie-Anne Bizouard, Violette Brisson

    Filters developed in order to detect short bursts of gravitational waves in interferometric detector outputs are compared according to three main points. Conventional Receiver Operating Characteristics (ROC) are first built for all the considered filters and for three typical burst signals. Optimized ROC are shown for a simple pulse signal in order to estima

  23. Namiko Mitarai, Hiizu Nakanishi

    Dynamical behavior of steady granular flow is investigated numerically in the inelastic hard sphere limit of the soft sphere model. We find distinctively different limiting behaviors for the two flow regimes, i.e., the collisional flow and the frictional flow. In the collisional flow, the hard sphere limit is straightforward; the number of collisions per par

  24. Tirthabir Biswas

    In this paper, I explain how gauge symmetry can be broken in a geometric way, à la Kaluza-Klein. In higher dimensional gravitational theories, one usually considers the extra dimensions to be ``frozen&#39;&#39; in time. However, the internal manifold is actually a dynamic entity. For example, its metric can change even if one expects its topological properti

  25. Olga Arias, Tame Gonzalez, Israel Quiros

    A linear relationship between the Hubble expansion parameter and the time derivative of the scalar field is assumed in order to derive exact analytic cosmological solutions to Einstein's gravity with two fluids: a barotropic perfect fluid of ordinary matter, together with a self-interacting scalar field fluid accounting for the dark energy in the universe. A

  26. Hy Trac, Ue-Li Pen

    We present a pedagogical review of some of the methods employed in Eulerian computational fluid dynamics (CFD). Fluid mechanics is governed by the Euler equations, which are conservation laws for mass, momentum, and energy. The standard approach to Eulerian CFD is to divide space into finite volumes or cells and store the cell-averaged values of conserved hy

  27. Ryusuke Ikeda

    Motivated by a {\it mean field-like} resistive behavior in magnetic fields commonly seen in various superconducting (SC) cuprates and organics with strong fluctuation, {\it quantum} SC fluctuation effects on resistive behaviors are reexamined by putting emphasis on their roles in the so-called {\it thermal} vortex liquid regime. By incorporating the quantum

  28. Rong-Gen Cai, Yun Soo Myung

    We discuss the holographic principle in a radiation-dominated, closed Friedmann-Robertson-Walker (FRW) universe with a positive cosmological constant. By introducing a cosmological D-bound on the entropy of matter in the universe, we can write the Friedmann equation governing the evolution of the universe in the form of the Cardy formula. When the cosmologic

  29. J. Nevalainen, R. Lieu, M. Bonamente, D. Lumb

    We present results on the spectroscopic analysis of XMM-Newton EPIC data of the central 0.5/h_50 Mpc regions of the clusters of galaxies Coma, A1795 and A3112. The temperature of the hot intracluster gas as determined by modeling the 2 - 7 keV PN and MOS data is consistent with that inferred from the FeXXV-FeXXVI line ratio. A significant warm emission compo

  30. Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone

    We establish the minimum time it takes for an initial state of mean energy E and energy spread DE to move from its initial configuration by a predetermined amount. Distances in Hilbert space are estimated by the fidelity between the initial and final state. In this context, we also show that entanglement is necessary to achieve the ultimate evolution speed w

  31. Richard Jozsa, Stuart Presnell

    We describe a universal information compression scheme that compresses any pure quantum i.i.d. source asymptotically to its von Neumann entropy, with no prior knowledge of the structure of the source. We introduce a diagonalisation procedure that enables any classical compression algorithm to be utilised in a quantum context. Our scheme is then based on the

  32. Don Weingarten

    We establish a necessary and sufficient condition for averages over complex valued weight functions on R^N to be represented as statistical averages over real, non-negative probability weights on C^N. Using this result, we show that many path-integrals for time-ordered expectation values of bosonic degrees of freedom in real-valued time can be expressed as s

  33. Silvia Giannini, Stefano Mancini, Paolo Tombesi

    We show the possibility to entangle radiation modes through a simple reflection on a moving mirror. The model of an optical cavity having a movable end mirror, and supporting different modes is employed. The mechanical motion of the mirror mediates information between the modes leading to an effective mode-mode interaction. We characterize the modes&#39; ent

  34. Gaston Garcia-Calderon, Jorge Villavicencio

    Time-dependent analytical solutions to Schrödinger&#39;s equation with quantum shutter initial conditions are used to investigate the issue of the tunneling time of forerunners in rectangular potential barriers. By using a time-frequency analysis, we find the existence of a regime characterized by the opacity of the barrier, where the maximum peak of a forer

  35. Rodrigo de Abreu

    We analyse a RLC circuit taking the Second Law of Thermodynamics into consideration.

  36. Jan-Willem Handgraaf, Titus S. van Erp, Evert Jan Meijer

    We present a density-functional theory based molecular-dynamics study of the structural, dynamical, and electronic properties of liquid methanol under ambient conditions. The calculated radial distribution functions involving the oxygen and hydroxyl hydrogen show a pronounced hydrogen bonding and compare well with recent neutron diffraction data, except for

  37. s. V. Nedea, A. P. J. Jansen, J. J. Lukkien

    We have used Dynamic Monte Carlo (DMC) methods and analytical techniques to analyze Single-File Systems for which diffusion is infinitely-fast. We have simplified the Master Equation removing the fast reactions and we have introduced a DMC algorithm for infinitely-fast diffusion. The DMC method for fast diffusion give similar results as the standard DMC with

  38. Randall D. Peters

    A model for harmonic oscillator damping due to the internal friction of solids has been developed, based on considerations of a long period pendulum. The assumption of a complex elastic modulus to describe stress-strain hysteresis in the support structure of the pendulum yields an expression for the figure of merit Q that agrees with many experiments involvi

  39. P. C. T. Dajello, P. R. Hauser

    A model to describe the arising of new structures in an initial homogeneous biological system is proposed. The essay is motivated by the intention to work on a non-equilibrium situation grouping together several mechanisms and processes as: catalytic reactions on a surface, diffusion, stimulated migration and selective heterogeneous reaction. A model for mor

  40. P K Biswas

    A new {\it ab initio} theoretical formulation to calculate $Z_{eff}$ and hence the positron annihilation rates is presented using the on-shell and half-offshell T-matrix scattering amplitudes without any explicit use of the scattering wave function. The formulation is exact and universal, as long as the dynamics of the system can be described by a Lippmann-S

  41. B. K. Agrawal, S. Shlomo, A. I. Sanzhur

    We use a fully self-consistent Hartree$-$Fock (HF) based continuum random phase approximation (CRPA) to calculate strength functions $S(E)$ and transition densities $ρ_t(r)$ for isoscalar giant resonances with multipolarities $L = 0$, 1 and 2 in $^{80}Zr$ nucleus. In particular, we consider the effects of spurious state mixing (SSM) in the isoscalar giant di

  42. T. Barford, M. C. Birse

    We study the scattering of a particle from a bound pair in an effective field theory using a distorted-wave renormalisation group method to find the power-counting for the three-body force terms. We find that three-body terms appear at lower orders than naively expected. They start with a marginal term that varies as a logarithm rather than a power of the en

  43. Xiao-Fu Lu, Bao-Xi Sun, Yu-Xin Liu, Hua Guo

    A nonlinear realization of SU(2) chiral symmetry spontaneous breaking approach is developed in the composite operator formalism. A Lagrangian including quark, gluon and Goldstone boson degrees of freedom of the chiral quark model is obtained from the QCD Lagrangian. A way to link the chiral symmetry spontaneous breaking formalism at hadron level and that at

  44. E. Widmann

    This talk gives an overview of the recent results on the precision spectroscopy of antiprotonic helium which was performed by the ASACUSA collaboration at the Antiproton Decelerator of CERN. The laser spectroscopy of energy levels of the antiproton has reached a relative accuracy of $\sim 10^{-7}$, and by comparing the experimental value for the transition w

  45. Barbara Wosiek

    The yields of identified particles have been measured at RHIC for Au+Au collisions at sqrt{s_NN} = 200 GeV using the PHOBOS spectrometer. The ratios of antiparticle to particle yields near mid-rapidity are presented. The first measurements of the invariant yields of charged pions, kaons and protons at very low transverse momenta are also shown.

  46. Steven Manly

    Elliptic flow and Bose-Einstein correlations have been measured in Au-Au collisions at $\sqrt{s_{_{NN}}} =$ 130 and 200 GeV using the PHOBOS detector at RHIC. The systematic dependencies of the flow signal on the transverse momentum, pseudorapidity, and centrality of the collision, as well as the beam energy are shown. In addition, results of a 3-dimensional

  47. A. Apte, A. Wurm, P. J. Morrison

    Extending the work of del-Castillo-Negrete, Greene, and Morrison, Physica D {\bf 91}, 1 (1996) and {\bf 100}, 311 (1997) on the standard nontwist map, the breakup of an invariant torus with winding number equal to the inverse golden mean squared is studied. Improved numerical techniques provide the greater accuracy that is needed for this case. The new resul

  48. M. R. Paul, K. -H. Chiam, M. C. Cross, P. F. Fischer

    Rayleigh-Bénard convection is studied and quantitative comparisons are made, where possible, between theory and experiment by performing numerical simulations of the Boussinesq equations for a variety of experimentally realistic situations. Rectangular and cylindrical geometries of varying aspect ratios for experimental boundary conditions, including fins an

  49. Julyan H. E. Cartwright, Diego L. Gonzalez, Oreste Piro

    Two and a half millennia ago Pythagoras initiated the scientific study of the pitch of sounds; yet our understanding of the mechanisms of pitch perception remains incomplete. Physical models of pitch perception try to explain from elementary principles why certain physical characteristics of the stimulus lead to particular pitch sensations. There are two bro

  50. Elisabetta De Angelis, Carlo M. Casciola, Victor S. L&#39;vov, Renzo Piva

    We address the phenomenon of drag reduction by dilute polymeric additive to turbulent flows, using Direct Numerical Simulations (DNS) of the FENE-P model of viscoelastic flows. It had been amply demonstrated that these model equations reproduce the phenomenon, but the results of DNS were not analyzed so far with the goal of interpreting the phenomenon. In or

  51. Claudio Meneghini

    We propose a new definition of geodesic completeness, based on analytical continuation in the complex domain: we apply this idea to Clifton-Pohl torus, relating, for each geodesic, completeness to the value of a function of initial conditions, called &#39;impulse&#39;.

  52. Alan T. Huckleberry, Joseph A. Wolf

    This is a survey of history, methods and developments in the theory of cycle spaces of flag domains, and new results on double fibration transforms and their applications.

  53. J. Crisp, L. Paris

    We show that each of the Artin groups of type $B_n$ and $D_n$ can be presented as a semidirect product $F \rtimes {\cal B}_n$, where $F$ is a free group and ${\cal B}_n$ is the $n$-string braid group. We explain how these semidirect product structures arise quite naturally from fibrations, and observe that, in each case, the action of the braid group ${\cal

  54. Baohua Fu

    We give some necessary conditions for the existence of a symplectic resolution for quotient singularities. The McKay correspondence is also worked out for these resolutions.

  55. Andreas Kriegl, Mark Losik, Peter W. Michor

    For a representation of a finite group $G$ on a complex vector space $V$ we determine when a holomorphic $\binom{p}{q}$-tensor field on the principle stratum of the orbit space $V/G$ can be lifted to a holomorphic $G$-invariant tensor field on $V$. This extends also to connections. As a consequence we determine those holomorphic diffeomorphisms on $V/G$ whic

  56. Iver Brevik, Kimball A. Milton, Sergei D. Odintsov

    Exact calculations are given for the Casimir energy for various fields in $R\times S^3$ geometry. The Green&#39;s function method naturally gives a result in a form convenient in the high-temperature limit, while the statistical mechanical approach gives a form appropriate for low temperatures. The equivalence of these two representations is demonstrated. So

  57. Richard C. Brower, Samir D. Mathur, Chung-I Tan

    We consider a model of brane world gravity in the context of non-conformal non-SUSY matter. In particular we modify the earlier strong coupling solution to the glueball spectrum in an $AdS^7$ Black Hole by introducing a Randall-Sundrum Planck brane as a UV cut-off. The consequence is a new normalizable zero mass tensor state, which gives rise to an effective

  58. M Tomaselli, L. C. Liu, T. Kuehl, W. Noertershaeuser

    The structure and dynamics of an n-particle system are described with coupled nonlinear Heisenberg&#39;s commutator equations where the nonlinear terms are generated by the two-body interaction that excites the reference vacuum via particle-particle and particle-hole excitations. Nonperturbative solutions of the system are obtained with the use of dynamic li

  59. N. B. Skachkov

    In the present note the expansion of the wave function of a massless particle (with the definite value of its helicity) over the untary irreducible representaions of the Lorentz group (defined on the light cone) is used as for the analog of the Fourier transformation for deriving of an equation in the relativistic configuration representation.

  60. I. Drozdov

    We consider the ground state energy of a spinor field in the background of a square well shaped magnetic flux tube. We use the zeta- function regularization and express the ground state energy as an integral involving the Jost function of a two dimensional scattering problem. We perform the renormalization by subtracting the contributions from first several

  61. Rudolf A. Frick

    We consider a relativistic superalgebra in the picture in which the time and spatial derivative cannot be presented in the operators of the particle. The supersymmetry generators as well as the Hamilton operators for the massive relativistic particles with spin zero and spin-1/2 are expressed in terms of the principal series of the unitary representations of

  62. Alexander Burinskii, Sergi R. Hildebrandt

    Properties of the rotating Kerr-Newman black hole solution allow to relate it with spinning particles. Singularity of black hole (BH) can be regularized by a metric deformation. In this case, as a consequence of the Einstein equations, a material source appears in the form of a relativistically rotating superconducting disk which replaces the former singular

  63. Enrique Alvarez, Juan Jose Manjarin

    The static potential, corresponding to the interaction of two heavy sources is computed for $\mathcal{N}=4$ Super Yang Mills in the strong &#39;t Hooft coupling regime by using the AdS/CFT conjecture and performing a computation of a rectangular Wilson loop at a finite distance of the boundary.

  64. Masato Ito

    We study the four-dimensional gravitational fluctuation on anisotropic brane tension embedded in braneworlds with vanishing bulk cosmological constant. In this setup, warp factors have two types (A and B) and we point out that the two types correspond to positive and negative tension brane, respectively. We show that volcano potential in the model of type A

  65. We-Fu Chang, John N. Ng

    We give a new configuration of split fermion positions in one extra dimension with two different Yukawa coupling strengths for up-type, $h_u$, and down-type, $h_d$, quarks at $\frac{h_u}{h_d}=36.0$. The new configurations can give enough CP violating (CPV) phase for accommodating all currently observed CPV processes. Therefore, a 5D standard model with split

  66. A. Dumitru

    I discuss the p_t distributions for high-multiplicity events originating from semi-classical variation of the gluon density of the proton.The multiplicity distribution measures the curvature of the effective action for the small-x gluon fields. For pA collisions at the RHIC and LHC colliders, semi-classically the multiplicity distribution reflects the distri

  67. G. Barenboim, J. Lykken

    Any local relativistic quantum field theory of Dirac-Weyl fermions conserves CPT. Here we examine whether a simple nonlocal field theory can violate CPT. We construct a new relativistic field theory of fermions, which we call ``homeotic&#39;&#39;, which is nonlocal but causal and Lorentz invariant. The free homeotic theory is in fact equivalent to free Dirac

  68. Alexander Mück, Apostolos Pilaftsis, Reinhold Rückl

    We study minimal 5-dimensional extensions of the Standard Model, in which all or only some of the SU(2)$_L$ and U(1)$_Y$ gauge fields and Higgs bosons propagate in the fifth compact dimension. In all the 5-dimensional settings, the fermions are assumed to be localized on a 3-brane. In addition, we present the consistent procedure for quantizing 5-dimensional

  69. F. Deppisch, H. Päs, A. Redelbach, R. Rückl

    We discuss constraints on the right-handed Majorana mass scale M_R of the SUSY see-saw model in the mSUGRA framework. The sensitivity of radiative lepton-flavor violating decays on M_R is compared with the reach in lepton-flavor violating channels at a future linear collider.

  70. Adam Biernacik, Karol Kolodziej

    Standard Model predictions for the reactions with six fermions in the final state relevant for top quark pair production and decay at linear colliders are discussed. An issue of the double resonance signal versus non doubly resonant background is addresed. Effects related to the off-mass-shell production of the t\bar{t}-pair are discussed.

  71. J. M. Butterworth, S. Butterworth

    A World Wide Web interface to a Monte Carlo validation and tuning facility is described. The aim of the package is to allow rapid and reproducible comparisons to be made between detailed measurements at high-energy physics colliders and general physics simulation packages. The package includes a relational database, a Java servlet query and display facility,

  72. T. M. Aliev, I. Kanik, A. Ozpineci

    We study semileptonic decay B --> eta l nu. The transition form factors for this decays are calculated by using light cone QCD sum rules.

  73. Jihn E. Kim, Hans Peter Nilles

    The model independent axion of string theory has a decay constant of order of the Planck scale. We explore the properties of this quintessence candidate (quintaxion) in the scheme of hidden sector supergravity breakdown. In models allowing for a reasonable $μ$ term, the hidden sector dynamics may lead to an almost flat potential responsible for the vacuum en

  74. Margarete Muhlleitner

    In the &#34;intense--coupling&#34; regime all Higgs bosons of the Minimal Supersymmetric extension of the Standard Model (MSSM) are rather light and have comparable masses of O(100 GeV). They couple maximally to electroweak gauge bosons, and for large ratios of the vacuum expectation values of the two Higgs doublet fields, tanβ, they interact strongly with t

  75. Stephen Godfrey

    In this mini-review I discuss three topics in meson spectroscopy. The production of heavy quarkonium states, S-wave scattering below 1 GeV, and exotic hybrid meson production. This is not intended to be a comprehensive review, just an overview of several topics of current interest.

  76. Stephen Godfrey, Jonathan L. Rosner

    The heavy quarkonium c\bar{c} and b\bar{b} resonances have a rich spectroscopy with numerous narrow S, P, and D-wave levels below the production threshold of open charm and beauty mesons. The mass predictions for these states are an important test of QCD calculations. We review some recent work describing the production of missing η_b(nS), 1^3D_J(b\bar{b}) a

  77. S. Scherer

    This article provides a pedagogical introduction to the basic concepts of chiral perturbation theory and is designed as a text for a two-semester course on that topic. Chapter 1 serves as a general introduction to the empirical and theoretical foundations which led to the development of chiral perturbation theory. Chapter 2 deals with QCD and its global symm

  78. Jakub Narebski

    The perturbative renormalization group for light-front QCD Hamiltonian produces a logarithmically rising interquark potential already in second order, when all gluons are neglected. There is a question if this approach produces also color van der Waals forces between heavy quarkonia and of what kind. This article shows that such forces do exist and estimates

  79. Laura Covi, David H. Lyth, Alessandro Melchiorri

    We evaluate new observational constraints on the two-parameter scale-dependent spectral index predicted by the running-mass inflation model by combining the latest Cosmic Microwave Background (CMB) anisotropy measurements with the recent 2dFGRS data on the matter power spectrum, with Lyman $α$ forest data and finally with theoretical constraints on the reion

  80. X. -H. Guo, A. W. Thomas

    The masses of heavy baryons containing a b quark have been calculated numerically in lattice QCD with pion masses which are much larger than its physical value. In the present work we extrapolate these lattice data to the physical mass of the pion by applying the effective chiral Lagrangian for heavy baryons, which is invariant under chiral symmetry when the

  81. R. Foot

    We show explicitly that four neutrino models of the 2+2 variety still provide an acceptable global fit to the solar, atmospheric and LSND neutrino data. The goodness of fit, defined in the usual way, is found to be 0.26 for the simplest such model. That is, we find that there is a 26% probability of obtaining a worse global fit to the neutrino data We also m

  82. Takeo Moroi, Tomo Takahashi

    We study the cosmic microwave background (CMB) anisotropy in the scenario with late-decaying scalar condensations which arise in many class of cosmological scenarios based on supersymmetric models. With such a scalar condensation ϕ, the CMB radiation we observe today originates to ϕand hence the CMB anisotropy is affected if ϕhas a primordial fluctuation. In

  83. Jonathan L. Feng, Mihoko M. Nojiri

    We present a pedagogical introduction to supersymmetry and supersymmetric models and give an overview of the potential of the linear collider for studying them. If supersymmetry is found, its discovery will bring with it many more questions than answers. These include: -Are the newly discovered particles really superpartners? -If not all superpartners are di

  84. G. L. Kane

    To make progress in learning the underlying fundamental theory, it will be necessary to combine bottom-up phenomenology and top-down analysis -- in particular, top-down is unlikely to succeed alone. Here I elaborate on the role of both, and describe obstacles that need to be overcome to help data point toward the underlying theory, as well as approaches that

  85. David H. Adams

    Topological charge of families of lattice gauge fields is defined fermionically via families index theory for the overlap Dirac operator. Certain obstructions to gauge invariance of the overlap chiral fermion determinant, as well as the lattice analogues of certain obstructions to gauge fixings without the Gribov problem, have natural descriptions in this co

  86. ZEUS Collaboration

    The azimuthal distribution of jets produced in the Breit frame in high-Q**2 deep inelastic e+p scattering has been studied with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb-1. The measured azimuthal distribution shows a structure that is well described by next-to-leading-order QCD predictions over the Q**2 range considered, Q**2>125 Ge

  87. Piotr T. Chrusciel, Rafe Mazzeo

    We analyze the horizon structure of families of space times obtained by evolving initial data sets containing apparent horizons with several connected components. We show that under certain smallness conditions the outermost apparent horizons will also have several connected components. We further show that, again under a smallness condition, the maximal glo

  88. K. H. Lockitch, J. L. Friedman, N. Andersson

    We study the inertial modes of slowly rotating, fully relativistic compact stars. The equations that govern perturbations of both barotropic and non-barotropic models are discussed, but we present numerical results only for the barotropic case. For barotropic stars all inertial modes are a hybrid mixture of axial and polar perturbations. We use a spectral me

  89. Carsten Gundlach

    In general relativity black holes can be formed from regular initial data that do not contain a black hole already. The space of regular initial data for general relativity therefore splits naturally into two halves: data that form a black hole in the evolution and data that do not. The spacetimes that are evolved from initial data near the black hole thresh

  90. M. Heller, Z. Odrzygozdz, L. Pysiak, W. Sasin

    We investigate spacetimes with their singular boundaries as noncommutative spaces. Such a space is defined by a noncommutative algebra on a transformation groupoid $Γ= E \times G$, where $E$ is the total space of the frame bundle over spacetime with its singular boundary, and $G$ its structural group. There is a bijective correspondence between unitary repre

  91. P. A. Hogan, E. M. O&#39;Shea

    We study gravitational waves propagating through an anisotropic Bianchi I dust-filled universe (containing the Einstein-de-Sitter universe as a special case). The waves are modeled as small perturbations of this background cosmological model and we choose a family of null hypersurfaces in this space-time to act as the histories of the wavefronts of the radia

  92. V. L. Kalashnikov

    It is shown that the accelerated expansion of the universe in the framework of the relativistic theory of gravitation can be achieved by the introduction of the quintessential term in the energy-momentum tensor. The value of the minimum scaling factor and the modern observational data for the density and state parameters of the matter give the rough estimati

  93. Carlos H. Marcondes, Luis Fernando Sayao

    This paper describes technological and methodological options to achieve interoperability in accessing electronic information resources, available in Internet, in the scope of Brazilian Digital Library in Science and Technology Project - BDL, developed by Brazilian Institute for Scientific and Technical Information - IBICT. It stresses the impact of the Web

  94. Gonzalo Alvarez, Slobodan Petrovic

    Web attacks, i.e. attacks exclusively using the HTTP protocol, are rapidly becoming one of the fundamental threats for information systems connected to the Internet. When the attacks suffered by web servers through the years are analyzed, it is observed that most of them are very similar, using a reduced number of attacking techniques. It is generally agreed

  95. V. Benci, C. Bonanno, S. Galatolo, G. Menconi

    We present some new results which relate information to chaotic dynamics. In our approach the quantity of information is measured by the Algorithmic Information Content (Kolmogorov complexity) or by a sort of computable version of it (Computable Information Content) in which the information is measured by the use of a suitable universal data compression algo

  96. A. V. Chubukov, A. M. Finkel&#39;stein, R. Haslinger, D. K. Morr

    We address the issue of how triplet superconductivity emerges in an electronic system near a ferromagnetic quantum critical point (FQCP). Previous studies found that the superconducting transition is of second order, and Tc is strongly reduced near the FQCP due to pair-breaking effects from thermal spin fluctuations. In contrast, we demonstrate that near the

  97. C. Rascon, M. E. Cates

    The effect of polydispersity on the phase diagram of a simple binary mixture is to split the binodal curve into cloud and shadow curves that cross at the critical point (which, in general, is not at the maximum of either curve). Recent theories of polydispersity have shown, in favorable cases, how to project the (infinite-dimensional) free energy of the poly

  98. D. Daghero, P. Mazzetti, A. Stepanescu, P. Tura

    We propose an analytical model devoted to explain the anisotropy of the electrical resistance observed below the critical temperature in granular high-Tc superconductors submitted to a magnetic field H. Reported experimental results obtained on a YBCO sample show that the superconducting transition occurs in two stages, with a steep drop of the resistance at

  99. I. Kakeya, T. Wada, K. Kadowaki

    We have investigated the Josephson plasma excitations in magnetic fields parallel to the $ab$-plane in Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ single crystals in a wide microwave frequency region (9.8 -- 75 GHz). It was found that there are two kind of phase-collective modes: one increases with magnetic fields in higher fields, approaching linear asymptotic dependence

  100. Miguel A. Munoz

    I review some open problems on the ever-growing field of non-equilibrium phase transitions, paying special attention to the formulation of such problems in terms of Langevin equations or, equivalently, field-theoretical descriptions, and their solution using renormalization