August 1997 arXiv papers — page 12

Mario Eudave-Muñoz, Ying-Qing Wu

We give three infinite families of examples of nonhyperbolic Dehn fillings on hyperbolic manifolds. A manifold in the first family admits two Dehn fillings of distance two apart, one of which is toroidal and annular, and the other is reducible and $\partial$-reducible. A manifold in the second family has boundary consisting of two tori, and admits two reduci

D. Anselmi, D. Z. Freedman, M. T. Grisaru, A. A. Johansen

For quantum field theories that flow between ultraviolet and infrared fixed points, central functions, defined from two-point correlators of the stress tensor and conserved currents, interpolate between central charges of the UV and IR critical theories. We develop techniques that allow one to calculate the flows of the central charges and that of the Euler

Yoonbai Kim

A reformulation of the Thirring model as a gauge theory on both continuum spacetime and discretized lattice is reviewed. In (1+1) dimensions, our result reproduces consistently the bosonization of the massless Thirring model. In (2+1) dimensions, the analysis by use of Schwinger-Dyson equation is shown to exhibit dynamical fermion mass generation when the nu

James D. Wells

The lightest supersymmetric particle (LSP) is stable in an R-parity conserving theory. In this article the steps needed to calculate the present day mass density of such a particle are detailed. It is shown that there can be a cosmologically significant amount of LSP dark matter in the universe. Furthermore, relic abundance considerations put an upper bound

James D. Wells

In R parity conserving supersymmetric theories the lightest superpartner (LSP) is stable. The LSPs may comprise a large fraction of the energy density of the current universe, which would lead to dramatic astrophysical consequences. In this talk, I discuss some of the main lessons we have learned about supersymmetric models from relic abundance consideration

O. J. P. Eboli, E. Gregores, F. Halzen

Collider experiments have recently measured the production cross section of hard jets separated by a rapidity gap as a function of transverse momentum and gap size. We show that these measurements reveal the relative frequencies for the production of rapidity gaps in quark-quark, quark-gluon and gluon-gluon interactions. The results are at variance with the

Matteo Cacciari

The state of the art of the theoretical calculations for heavy quarks photoproduction is reviewed. The full fixed order next-to-leading order massive calculation and the resummation of large log(p_T/m) terms for differential cross sections are described. The implementation of a non-perturbative fragmentation function describing the c -> D* meson transition i

C. Spieles, H. Stoecker, C. Greiner

The deconfinement transition region between hadronic matter and quark-gluon plasma is studied for finite volumes. Assuming simple model equations of state and a first order phase transition, we find that fluctuations in finite volumes hinder a sharp separation between the two phases around the critical temperature, leading to a rounding of the phase transiti

W. Grimus, P. Stockinger

We consider elastic antineutrino-electron scattering taking into account possible effects of neutrino masses and mixing and of neutrino magnetic moments and electric dipole moments. Having in mind antineutrinos produced in a nuclear reactor we compute, in particular, the weak-electromagnetic interference terms which are linear in the magnetic (electric dipol

B. Bajc, S. Fajfer, R. J. Oakes, S. Prelovšek

We analyze charm meson semileptonic $D \to V l ν_l$ and $D\to P l ν_l$ and nonleptonic $D \to P V$, $D \to PP$ and $D \to VV$ decays within a model which combines the heavy quark effective Lagrangian and chiral perturbation theory.

Maria Krawczyk, A. Zembrzuski

The sensitivity of the Deep Inelastic Compton (DIC) scattering at HERA to the structure of the virtual photon is discussed. It is demonstrated that the gluonic content of the virtual photon can be pinned down by measuring the photons with $p_T \sim 5 $ GeV in the proton direction.

M. F. McDermott

Following an introduction which explains some basic ideas about diffraction, the semiclassical approach to diffraction in deep inelastic scattering (DIS) is outlined. Some phenomenological tests of this picture, concerning the $p_{\perp}$ and mass spectra of open charm and jet production are given.

J. Kalinowski, R. Rueckl, H. Spiesberger, P. M. Zerwas

In supersymmetric theories with R-parity breaking, sleptons can be produced in quark-antiquark annihilation at the Tevatron through interactions in which two quark fields are coupled to a slepton field. If at the same time trilinear slepton-lepton-lepton couplings are present, the sleptons can be searched for as resonances in $p\bar{p}\to \tildeν \to l^+l^-$

Yu. M. Shabelski, A. G. Shuvaev

The azimutal correlations of heavy quarks produced in the high energy $pp$ ($p\bar{p}$) collisions are calculated in the framework of QCD without the usual assumptions of the parton model. The virtual nature of the interacting gluons as well as their transverse motion and different polarizations are taken into account. We give some predictions for the azimut

M. Goeckeler, R. Horsley, L. Mankiewicz, H. Perlt

We perform a Monte Carlo calculation of the second moment of the polarised valence quark distributions in the nucleon, using quenched Wilson fermions. The special feature of this moment is that it is directly accessible experimentally. At a scale of $μ\approx 2$GeV we find $Δ^{(1)}u = 0.198(8)$, $Δ^{(1)}d = -0.0477(33)$. We compare these numbers with recent

I. Montvay

The difficulties of defining chiral gauge theories non-perturbatively suggest a vector-like extension of the standard model with three mirror fermion families. Some phenomenological implications of such an extension are discussed.

Hitoshi Ito

A relativistic equation is deduced for the bound state of two particles, by assuming a proper boundary condition for the propagation of the negative-energy states. It reduces to the (one-body)Dirac equation in the infinite limit of one of the constituent mass. It also has the symmetries to assure the existence of the anti-bound-state with the same mass. The

H. Weigel, L. Gamberg, H. Reinhardt

We study nucleon structure functions within the bosonized Nambu-Jona-Lasinio (NJL) model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron-nucleon scattering. A comparison with a low-scale parametrization shows that the model reproduces the gross features of the empirical structure function

L. Gamberg, H. Reinhardt, H. Weigel

We study nucleon structure functions within the bosonized Nambu--Jona--Lasinio model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron--nucleon scattering. A comparison with a low--scale parametrization shows that the model reproduces the gross features of the empirical structure functions.

Alan C. Irving, James C. Sexton, Eamonn Cahill

Recent developments and applications of approximate actions for full lattice QCD are described. We present first results based on the stochastic estimation of the fermion determinant on $12^3\times 24$ configurations at $β=5.2$.

Franz Embacher

The question is raised whether the unique decomposition of the physical Hilbert space, as emerging in the refined algebraic quantization of a constrained system, may be understood in terms of the old Klein-Gordon type quantization.

Vladimir S. Mashkevich

This paper is a sequel to the series of papers [gr-qc/9409010, gr-qc/9505034, gr-qc/9603022, gr-qc/9609035, gr-qc/9609046, gr-qc/9704033, gr-qc/9704038]. Gravitational autolocalization of a body is considered. A self-consistent problem is solved: A quantum state of the center of mass of the body gives rise to a classical gravitational field, and the state, o

Reginald T. Cahill, Christopher M. Klinger

We further deconstruct Heraclitean Quantum Systems giving a model for a universe using pregeometric notions in which the end-game problem is overcome by means of self-referential noise. The model displays self-organisation with the emergence of 3-space and time. The time phenomenon is richer than the present geometric modelling.

Masahiro Shiroishi, Hideaki Ujino, Miki Wadati

The SO(4) invariance of the transfer matrix for the one-dimensional Hubbard model is clarified from the QISM (quantum inverse scattering method) point of view. We demonstrate the SO(4) symmetry by means of the fermionic R-matrix, which satisfy the graded Yang-Baxter relation. The transformation law of the fermionic L-operator under the SO(4) rotation is iden

Jaroslav Fabian, Philip B. Allen

Using a realistic model, the mode Gruneisen parameters and the temperature dependent coefficient of linear thermal expansion are calculated for amorphous silicon. The resulting values of the Gruneisen parameters differ from the crystalline case in having all diversity suppressed, except for a minority of high-frequency localized and low-frequency resonance m

Jae Woo Lee

We have studied a model of self-attracting walk proposed by Sapozhnikov using Monte Carlo method. The mean square displacement $ < R^2(t) > \sim t^{2ν}$ and the mean number of visited sites $ < S(t) > \sim t^{k}$ are calculated for one-, two- and three-dimensional lattice. In one dimension, the walk shows diffusive behaviour with $ν=k=1/2$. However, in two a

P. Bourges, H. Casalta, A. S. Ivanov, D. Petitgrand

A systematic inelastic neutron scattering study of the superexchange interaction in three different undoped monolayer cuprates (La_2CuO_4, Nd_2CuO_4 and Pr_2CuO_4) has been performed using conventional triple axis technique. We deduce the in-plane antiferromagnetic (AF) superexchange coupling $J$ which actually presents no simple relation versus crystallogra

Somendra M. Bhattacharjee, A. Baumgärtner

We have studied the aging effect on the dynamics of unbinding of a double stranded directed polymer in a random medium. By using the Monte Carlo dynamics of a lattice model in two dimensions, for which disorder is known to be relevant, the unbinding dynamics is studied by allowing the bound polymer to relax in the random medium for a waiting time and then al

D. A. Gorokhov, G. Blatter

The decay rate of metastable states is determined at high temperatures by thermal activation, whereas at temperatures close to zero quantum tunneling is relevant. At some temperature $T_{c}$ the transition from classical to quantum-dominated decay occurs. The transition can be first-order like, with a discontinuous first derivative of the Euclidean action, o

C. J. Lambert, R. Raimondi

This article is an overview of recent experimental and theoretical work on transport in phase-coherent hybrid nanostructures, with particular emphasis on dc electrical conduction. A summary of multiple scattering theory and the quasi-classical methods is presented and comparisons between the two are made. Several paradigms of phase-coherent transport are dis

S. Lubeck, K. D. Usadel

We consider the Bak-Tang-Wiesenfeld sandpile model on square lattices in different dimensions (D>=6). A finite size scaling analysis of the avalanche probability distributions yields the values of the distribution exponents, the dynamical exponent, and the dimension of the avalanches. Above the upper critical dimension D_u=4 the exponents equal the known mea

Charlie Kane, Leon Balents, Matthew Fisher

We argue that long-range Coulomb forces convert an isolated (N,N) armchair carbon nanotube into a strongly-renormalized *Luttinger liquid*. At high temperatures, we find anomalous temperature dependences for the interaction and impurity contributions to the resistivity, and similar power-law dependences for the local tunneling density of states. At low tempe

Bonnie L. Webber

This paper examines demonstrative pronouns used as deictics to refer to the interpretation of one or more clauses. Although this usage is frowned upon in style manuals (for example Strunk and White (1959) state that ``This. The pronoun &#39;this&#39;, referring to the complete sense of a preceding sentence or clause, cannot always carry the load and so may p

Alison J. Cawsey, Bonnie L. Webber, Ray B. Jones

Good communication is vital in healthcare, both among healthcare professionals, and between healthcare professionals and their patients. And well-written documents, describing and/or explaining the information in structured databases may be easier to comprehend, more edifying and even more convincing, than the structured data, even when presented in tabular

Detlef Lohse, Sascha Hilgenfeldt

In this paper we elaborate on the idea [Lohse et al., Phys. Rev. Lett. 78, 1359-1362 (1997)] that (single) sonoluminescing air bubbles rectify argon. The reason for the rectification is that nitrogen and oxygen dissociate and their reaction products dissolve in water. We give further experimental and theoretical evidence and extend the theory to other gas mi

John Magorrian, Scott Tremaine, Douglas Richstone, Ralf Bender

We construct dynamical models for a sample of 36 nearby galaxies with Hubble Space Telescope photometry and ground-based kinematics. The models assume that each galaxy is axisymmetric, with a two-integral distribution function, arbitrary inclination angle, a position-independent stellar mass-to-light ratio Upsilon, and a central massive dark object (MDO) of

Brad M. S. Hansen, E. Sterl Phinney

We analyse the sample of pulsar proper motions, taking detailed account of the selection effects of the original surveys. We treat censored data using survival statistics. From a comparison of our results with Monte Carlo simulations, we find that the mean birth speed of a pulsar is 250-300 km/s, rather than the 450 km/s foundby Lyne & Lorimer (1994). The re

S. Markoff, F. Melia, I. Sarcevic

The recent detection of a gamma-ray flux from the direction of the Galactic center by EGRET on the Compton GRO raises the question of whether this is a point source (possibly coincident with the massive black hole candidate Sgr A*) or a diffuse emitter. Using the latest experimental particle physics data and theoretical models, we examine in detail the gamma

Tom MacFarland, Jakob Pichlmeier, Frazer Pearce, Hugh Couchman

We have developed a parallel Particle-Particle, Particle-Mesh (P^3M) simulation code for the T3E well suited to studying the time evolution of systems of particles interacting via gravity and gas forces in cosmological contexts. The parallel code is based upon the public-domain serial Adaptive P^3M code of Couchman et al(1). The algorithm resolves gravitatio

J. C. Miller, T. Shahbaz, L. A. Nolan

We examine the status of the threat posed to stellar-mass black hole candidates by the possible existence of Q-stars (compact objects with an exotic equation of state which might have masses well above the normally-accepted maximum for standard neutron stars). We point out that Q-stars could be extremely compact (with radii less than 1.5 times the correspond

S. A. Levshakov, W. H. Kegel, F. Takahara

By using a Reverse Monte Carlo technique aimed at the inverse problem in the analysis of the H+D Ly-a absorption from QSO spectra we have estimated the physical parameters of the gas and the large-scale line of sight velocity structure towards Q1009+2956 at z = 2.504 (observations by Burles and Tytler, astro-ph/9603070). We show that for a precise evaluation

W. H. Kegel, S. A. Levshakov

We show that in stochastic large scale velocity fields superposed on the general Hubble flow, the formation of the GP-depression in QSO spectra is intimately related to the formation of the absorption-line structure usually called `Ly-alpha forest&#39;. Therefore the HI-density in the diffuse IGM might be substaintially underestimated if one determines the G

Jack F. Gallimore, Stefi A. Baum, Christopher P. O&#39;Dea

Active galactic nuclei (AGN) are generally accepted to be powered by the release of gravitational energy in a compact accretion disk surrounding a massive black hole. Such disks are also necessary to collimate powerful radio jets seen in some AGN. The unifying classification schemes for AGN further propose that differences in their appearance can be attribut

Erik Hog, Chris Flynn

Parallaxes for 581 bright K giants have been determined using the Hipparcos satellite. We combine the trigonometric parallaxes with ground based photometric data to determine the K giant absolute magnitudes. For all these giants, absolute magnitude estimates can also be made using the intermediate band photometric DDO system (Janes 1975, 1979). We compare th

Takashi Nakamura, Misao Sasaki, Takahiro Tanaka, Kip S. Thorne

If MACHOs are black holes of mass about 0.5 solar mass, they must have been formed in the early universe when the temperature was about 1 GeV. We estimate that in this case in our galaxy&#39;s halo out to about 50kpc there exist about half billion black hole binaries whose coalescence times are comparable to the age of the universe, so that the coalescence r

R. Benton Metcalf, Joseph Silk

Some aspects of gravitational lensing by large scale structure (LSS) are investigated. We show that lensing causes the damping tail of the cosmic microwave background (CMB) power spectrum to fall less rapidly with decreasing angular scale than previously expected. This is due to a transfer of power from larger to smaller angular scales which produces a fract

Carlos Simpson

We define notions of direct and inverse limits in an $n$-category. We prove that the $n+1$-category $nCAT&#39;$ of fibrant $n$-categories admits direct and inverse limits. At the end we speculate (without proofs) on some applications of the notion of limit, including homotopy fiber product and homotopy coproduct for $n$-categories, the notion of $n$-stack, r

Hugo Martel, Premana Premadi, Richard Matzner

We simulate the growth of large-scale structure in the universe using a N-body code. By combining these simulations with a Monte-Carlo method, we generate galaxy distributions at present that reproduces the observed morphology-density relation, with most ellipticals concentrated in the densest regions. By &#34;tying&#34; each galaxy to its nearest particle,

Amihay Hanany, Gilad Lifschytz

We discuss M(atrix) theory compactification on T^6. This theory is described by the large N limit of the world volume theory, of N Kaluza-Klein monopoles in eleven dimensions. We discuss the BPS states, and their arrangement in E_6 multiplets. We then propose the formulation of the world volume theory of KK monopoles in eleven dimensions that decouples from

N. Dorey, V. V. Khoze, M. P. Mattis

We propose explicit formulae for the integration measure on the moduli space of charge-n ADHM multi-instantons in N=1 and N=2 supersymmetric gauge theories. The form of this measure is fixed by its (super)symmetries as well as the physical requirement of clustering in the limit of large spacetime separation between instantons. We test our proposals against k

Jorma Louko, Bernard F. Whiting, John L. Friedman

We consider the Hamiltonian dynamics of spherically symmetric Einstein gravity with a thin null-dust shell, under boundary conditions that fix the evolution of the spatial hypersurfaces at the two asymptotically flat infinities of a Kruskal-like manifold. The constraints are eliminated via a Kuchar-type canonical transformation and Hamiltonian reduction. The

Leo Radzihovsky, John Toner

We study the shape, elasticity and fluctuations of the recently predicted (cond-mat/9510172) and subsequently observed (in numerical simulations) (cond-mat/9705059) tubule phase of anisotropic membranes, as well as the phase transitions into and out of it. This novel phase lies between the previously predicted flat and crumpled phases, both in temperature an

Anders Irbäck, Erik Sandelin

We study a simple heteropolymer model containing sequence-independent local interactions on both square and triangular lattices. Sticking to a two-letter code, we investigate the model for varying strength $κ$ of the local interactions; $κ=0$ corresponds to the well-known HP model [K.F. Lau and K.A. Dill, Macromolecules 22, 3986 (1989)]. By exhaustive enumer

P. K. Townsend

An `algebraic&#39; approach to M-theory is briefly reviewed, and a proposal is made for a similar algebraic structure underlying the $T^9$ compactification of `M(embrane) theory&#39;, i.e. the M(atrix) model with area-preserving diffeomorphism gauge group.

Everton M. C. Abreu, Nelson R. F. Braga

A BPHZ renormalized form for the master equation of the field antifiled (or BV) quantization has recently been proposed by De Jonghe, Paris and Troost. This framework was shown to be very powerful in calculating gauge anomalies. We show here that this equation can also be applied in order to calculate a global anomaly (anomalous divergence of a classically c

Jan O. Conrad

Reviewing the cancellation of local anomalies of M-theory on R^10 x S^1/Z_2 the Yang-Mills coupling constant on the boundaries is rederived. The result is lambda^2 = 2^(1/3) (2 pi) (4 pi kappa^2)^(2/3) corresponding to eta = lambda^6/kappa^4 = 256 pi^5 in the `upstairs&#39; units used by Horava and Witten and differs from their calculation. It is shown that

Z. Gedik, M. Bayindir

A method, analogous to supersymmetry transformation in quantum mechanics, is developed for a particle in the lowest Landau level moving in an arbitrary potential. The method is applied to two-dimensional potentials formed by Dirac delta scattering centers. In the periodic case, the problem is solved exactly for rational values of the magnetic flux (in units

N. O. Agasian, K. Zarembo

The thermodynamics of 3d adjoint Higgs model is considered. We study the properties of the Polyakov loop correlators and the critical behavior at the deconfinement phase transition. Our main tool is a reduction to the 2d sine-Gordon model. The Polyakov loops appear to be connected with the soliton operators in it. The known exact results in the sine-Gordon t

O. B. Zaslavskii

Nonextreme black hole in a cavity within the framework of the canonical or grand canonical ensemble can approach the extreme limit with a finite temperature measured on a boundary located at a finite proper distance from the horizon. In spite of this finite temperature, it is shown that the one-loop contribution $S_{q\text{ }}$of quantum fields to the thermo

N. S. Branco, Beatriz M. Boechat

The phase-diagram of the two-dimensional Blume-Capel model with a random crystal field is investigated within the framework of a real-space renormalization group approximation. Our results suggest that, for any amount of randomness, the model exhibits a line of Ising-like continuous transitions, as in the pure model, but no first-order transition. At zero te

Kieran G. O&#39;Grady

Moduli spaces of semistable torsion-free sheaves on a K3 surface $X$ are often holomorphic symplectic varieties, deformation equivalent to a Hilbert scheme parametrizing zero-dimensional subschemes of $X$. In fact this should hold whenever semistability is equivalent to stability. In this paper we study a typical &#34;opposite&#34; case, i.e. the moduli spac

O. Abe, O. Tabata

We investigate the behavior of small perturbations around the Kaluza-Klein monopole in the five dimensional space-time. We find that the even parity gravitational wave does not propagate in the five dimensional space-time with Kaluza-Klein monopole provided that the gravitational wave is constant in the fifth direction. We conclude that a gravitational wave

T. Hatsuda

Pade approximants (PA&#39;s) are constructed from the perturbative coefficients of the free energy through O(g^5) in hot QCD. Pade summation is shown to reduce the renormalization-scale dependence substantially even at temperature (T) as low as 250 MeV. Also, PA&#39;s predict that the free energy does not deviate more than 10 % from the Stefan-Boltzmann limi

Michael Martin Nieto

I first review a) the flowering of coherent states in the 1960&#39;s, yet b) the discovery of coherent states in 1926, and c) the flowering of squeezed states in the 1970&#39;s and 1980&#39;s. Then, with the background of the excitement over the then new quantum mechanics, I describe d) the discovery of squeezed states in 1927.

M. Rigo, F. Mota-Furtado, P. F. O&#39;Mahony

The set of continuous norm-preserving stochastic Schrodinger equations associated with the Lindblad master equation is introduced. This set is used to describe the localization properties of the state vector toward eigenstates of the environment operator. Particular focus is placed on determining the stochastic equation which exhibits the highest rate of loc

J Anthony de Wet

The purpose of this contribution is to show how a nuclear field theory follows naturally from the structure of four-dimensional Riemannian geometry. A Yang-Mills field is introduced by constructing fibres that include all possible exchanges of spin, parity and charge such that the collective quantum numbers remain the same. In this way O(4) internal symmetry

V. A. Gani, A. E. Kudryavtsev, V. M. Weinberg

The states of hydrogen atom with principal quantum number $n\le3$ and zero magnetic quantum number in constant homogeneous magnetic field ${\cal H}$ are considered. The coefficients of energy eigenvalues expansion up to 75th order in powers of ${\cal H}^2$ are obtained for these states. The series for energy eigenvalues and wave functions are summed up to ${

M. Luecke, A. Szprynger

The effect of thermally generated bulk stochastic forces on the statistical growth dynamics of forwards bifurcating propagating macroscopic patterns is compared with the influence of fluctuations at the boundary of a semiinfinite system, $0<x$. To that end the linear complex Ginzburg-Landau amplitude equation with additive stochastic forcing is solved by a s

C. A. Bertulani, P. Lotti, H. Sagawa

We study the energy dependence of the cross sections for nucleon removal of 8B projectiles. It is shown that the Glauber model calculations with nucleon-nucleon t-matrix reproduce well the energy dependence of the breakup cross sections of 8B. A DWBA model for the breakup cross section is also proposed and results are compared with those of the Glauber model

Naohito Nakazawa, Daiji Ennyu

We apply stochastic quantization method to real symmetric matrix-vector models for the second quantization of non-orientable strings, including both open and closed strings. The Fokker-Planck hamiltonian deduces a well-defined non-orientable open-closed string field theory at the double scaling limit of the matrix model. There appears a new algebraic structu

C. F. de Araujo,, L. Tomio, S. K. Adhikari, T. Frederico

A recently proposed renormalization scheme can be used to deal with nonrelativistic potential scattering exhibiting ultraviolet divergence in momentum space. A numerical application of this scheme is made in the case of potential scattering with $r^{-2}$ divergence for small r, common in molecular and nuclear physics, by the use of cut-offs in momentum and c

Hirotaka Sugawara

F theory and M theory are formulated as gauge theories of area preserving diffeomorphism algebra. Our M theory is shown to be 1-brane formulation rather than 0-brane formulation of M theory of Banks, Fischler, Shenker and Susskind and the F theory is shown to be 1-brane formulation rather than -1-brane formulation of type IIB matrix theory of Ishibashi, Kawa

Deog Ki Hong

We investigate the zero temperature chiral phase transition in (2+1)-dimensional QED in the presence of a Chern-Simons term, changing the number of fermion flavors. In the symmetric phase, there are no light degrees of freedom even at the critical point. Unlike the case without a Chern-Simons term, the phase transition is first-order.

Kazuo Ghoroku

We examine the behavior of the vortex defects, which are represented by the sine-Gordon potential, on the world-sheet when a solitonic d-5 brane is existing in the d-dimensional target space. The d-5 brane solution is obtained as an extension of 5-brane in 10d supergravity. It is shown that the vortices of any charge should be dissociated to the free gas whe

F. E. Close, I. Dunietz, P. R. Page, S. Veseli

Hybrid charmonium with mass ~4 GeV could be produced via a c c.bar color-octet component in b->c c.bar s. These states could be narrow and could have a significant branching ratio to light hadrons, perhaps enhanced by glueballs. Decays to gluonic hadrons could make a sizable contribution to B->no charm decays. Experimental signatures and search strategies ar

T. Han, R. Hempfling

In models where supersymmetry breaking is communicated into the visible sector via gauge interactions the lightest supersymmetric particle is typically the gravitino which is too light to account for cold dark matter. We point out that the lightest messenger sneutrinos with mass in the range of one to three TeV may serve as cold dark matter over most of the

S. P. Klevansky, A. Ogura, J. Hüfner

Transport theory for an interacting fermionic system is reviewed and applied to the chiral Lagrangian of the Nambu-Jona-Lasinio model. Two expansions must be applied: an expansion in the inverse number of colors, $1/N_c$, due to the nature of the strong coupling theory, and a semiclassical expansion, in powers of $\hbar$. The quasiparticle approximation is i

Sergio Scopetta, Vicente Vento, Marco Traini

Using a simple picture of the constituent quark as a composite system of point-like partons, we construct the parton distributions by a convolution between constituent quark momentum distributions and constituent quark structure functions. We evaluate the latter at a low hadronic scale with updated phenomenological information, and we build the momentum dist

E. Laenen, G. A. Schuler

We present the first calculation of QED radiative corrections to deep-inelastic electron-photon scattering in terms of those variables that are reconstructed in measurements of the photon structure function in electron-positron collisions. In order to cover the low-$Q^2$ region, we do not invoke the QCD-improved parton model but rather express our results in

Kei-Ichi Kondo, Takeharu Murakami

In the normal phase (where no dynamical fermion mass generation occurs) of the D-dimensional quantum electrodynamics with $N_f$ flavors of fermions, we derive an integral equation which should be satisfied by (the inverse of) the wave function renormalization of the fermion in the Landau gauge. For this we use the inverse Landau-Khalatnikov transformation co

M. N. Dubinin, H. S. Song

We present the results of complete tree level calculation for W boson production processes e^- p -> e^- mu^+ nu_mu X and e^- p -> e^- mu^- nu_mubar X introducing anomalous WWgamma and WWZ couplings. Detailed results for the distributions of final state particles are obtained. In the region of small momentum transferred we calculate the contribution of hadron

Cong-Feng Qiao, Xiao-Fei Zhang, Wei-Qin Chao

$J/ψ$ production cross section considering the contributions of both color-singlet and color-octet $c\bar c$ channels is calculated. The result is used to study the suppression of $J/ψ$ in nuclear collisions. With absorption cross sections for $(c \bar c)_8$ $σ_{abs}^8\simeq 11mb $ and $(c \bar c)_1$ $σ_{abs}^1\simeq 0mb $ the p-A and A-B data except for Pb-

ZEUS Collaboration

We present a measurement of the inelastic, non diffractive J/$ψ$ photoproduction cross section in the reaction $e^{+} p \to e^{+} {J}/ψX$ with the ZEUS detector at HERA. The J/$ψ$ was identified using both the $μ^{+}μ^{-}$ and $e^{+}e^{-}$ decay channels and events were selected within the range $0.4<z<0.9$ ($0.5<z<0.9$) for the muon (electron) decay mode, w

Karin Daum

Recent results on inclusive D^0 and D^{*+-} production in deeply inelastic ep scattering at sqrt(s)=301 GeV are summarized. The data have been collected by the H1 and ZEUS experiments at HERA. The total and the differential cross sections are discussed in the framework of LO and NLO QCD predictions. The data exhibit clear evidence for boson gluon fusion domi

Warner A. Miller

The Hilbert action is derived for a simplicial geometry. I recover the usual Regge calculus action by way of a decomposition of the simplicial geometry into 4-dimensional cells defined by the simplicial (Delaunay) lattice as well as its dual (Voronoi) lattice. Within the simplicial geometry, the Riemann scalar curvature, the proper 4-volume, and hence, the R

Yasunori Fujii

Cosmological solutions of the Brans-Dicke theory with an added cosmological constant are investigated with an emphasis to select a conformal frame in order to implement the scenario of a decaying cosmological constant, featuring an ever growing scalar field. We focus particularly on Jordan frame, the original frame with the nonminimal coupling, and conformal

P. R. Hammar, Daniel H. Reich, C. Broholm, F. Trouw

Cu_{2}(1,4-diazacycloheptane)_{2}Cl_{4} contains double chains of spin 1/2 Cu^{2+} ions. We report ac susceptibility, specific heat, and inelastic neutron scattering measurements on this material. The magnetic susceptibility, $χ(T)$, shows a rounded maximum at T = 8 K indicative of a low dimensional antiferromagnet with no zero field magnetic phase transitio

Ayse Erzan, Ayse Gorbon

A kinetics built upon $q$-calculus, the calculus of discrete dilatations, is shown to describe diffusion on a hierarchical lattice. The only observable on this ultrametric space is the &#34;quasi-position&#34; whose eigenvalues are the levels of the hierarchy, corresponding to the volume ofphase space available to the system at any given time. Motion along t

B. Derrida, J. L. Lebowitz, E. R. Speer

The asymmetric simple exclusion process (ASEP) on a one-dimensional lattice is a system of particles which jump at rates $p$ and $1-p$ (here $p>1/2$) to adjacent empty sites on their right and left respectively. The system is described on suitable macroscopic spatial and temporal scales by the inviscid Burgers&#39; equation; the latter has shock solutions wi

Fu-Chun Zhang, T. M. Rice

This is a comment on a paper published by V. Dobrosavljevic et al. in Phys. Rev. Lett. 79, 455 (1997).

Hajime Tanaka

We propose here a new mechanism of droplet coarsening in phase-separating fluid mixtures. In contrast to the conventional understanding that there are no interactions between droplets in the late stage of spinodal decomposition, we demonstrate the existence of interactions between droplets that is caused by the coupling between diffuse concentration change a

Hajime Tanaka

We show here a general model of phase separation in isotropic condensed matter, namely, a viscoelastic model. We propose that the bulk mechanical relaxation modulus that has so far been ignored in previous theories plays an important role in viscoelastic phase separation in addition to the shear relaxation modulus. In polymer solutions, for example, attracti

Prabir K. Mukherjee, Kisor Mukhopadhyay

We propose a Landau-de Gennes phenomenological model to describe the pressure induced smectic A-nematic phase transition. The pressure induced smectic A phase transitions are discussed for varying coupling between orientational and translational order parameter. Increasing the pressure, the first order nematic-smectic A transition becomes second order at a t

Alain Chiolero, Daniel Loss

We study macroscopic quantum coherence in antiferromagnetic molecular magnets in the presence of magnetic fields. Such fields generate artificial tunnel barriers with externally tunable strength. We give detailed semi-classical predictions for the tunnel splitting in various regimes for low and high magnetic fields. We show that the tunneling dynamics of the

V. J. Goldman

comment on cond-mat/97063007 and cond-mat/9707289

Dorit Abusch, Mats Rooth

The paper considers participles such as &#34;unknown&#34;, &#34;identified&#34; and &#34;unspecified&#34;, which in sentences such as &#34;Solange is staying in an unknown hotel&#34; have readings equivalent to an indirect question &#34;Solange is staying in a hotel, and it is not known which hotel it is.&#34; We discuss phenomena including disambiguation of

Siegfried Grossmann, Detlef Lohse, Achim Reeh

The scaling behavior of the SO(3) irreducible amplitudes $d_n^l(r)$ of velocity structure tensors (see L&#39;vov, Podivilov, and Procaccia, Phys. Rev. Lett. (1997)) is numerically examined for Navier-Stokes turbulence. Here, l characterizes the irreducible representation by the index of the corresponding Legendre polynomial, and n denotes the tensorial rank,

Sang-Yoon Kim

We consider a permanent magnetic dipole in an oscillating magnetic field. This magnetic oscillator has two dynamical symmetries. With increasing the amplitude $A$ of the magnetic field, dynamical behaviors associated with the symmetries are investigated. For small $A$, there exist symmetric states with respect to one of the two symmetries. However, such symm

P. P. Avelino, R. R. Caldwell, C. J. A. P. Martins

The cosmic string scenario in an open universe is developed -- including the equations of motion, a model of network evolution, the large angular scale CMB temperature anisotropy, and the power spectrum of density fluctuations produced by cosmic strings with dark matter. First we derive the equations of motion for cosmic string in an open FRW space-time and

D. Calzetti, G. Meurer, R. Bohlin, D. Garnett

(Abridged) Ultraviolet and optical narrow and broad band images of NGC5253 obtained with the HST WFPC2 are used to derive the properties of the dust distribution and the recent star formation history of this metal-poor dwarf galaxy. Corrections for the effects of dust are important in the center of NGC5253: dust reddening is markedly inhomogeneous across the