arXiv papers from August 1999

Craig A. Tracy, Harold Widom

This paper is a brief review of recent developments in random matrix theory. Two aspects are emphasized: the underlying role of integrable systems and the occurrence of the distribution functions of random matrix theory in diverse areas of mathematics and physics.

Sang Pyo Kim

We study canonical quantization of a closed Euclidean universe with a cosmological constant and a massless scalar field. The closed Euclidean universe with an ordinary matter state can be matched at a finite radius only with the closed Lorentzian universe with the Wick-rotated exotic state. The exotic state provides the Lorentzian universe with a potential b

Michele Maggiore

Gravitational-wave experiments with interferometers and with resonant masses can search for stochastic backgrounds of gravitational waves of cosmological origin. We review both experimental and theoretical aspects of the search for these backgrounds. We give a pedagogical derivation of the various relations that characterize the response of a detector to a s

Sebastian Eggert

Explicit predictions for Scanning Tunneling Microscopy (STM) on interacting one-dimensional electron systems are made using the Luttinger liquid formalism. The STM current changes with distance from an impurity or boundary in a characteristic way, which reveals the spin-charge separation and the interaction strength in the system. The current exhibits Friede

Mitake Miyazaki, Keita Kishigi, Yasumasa Hasegawa

We study the transition temperature Tc(H) of a quasi-one-dimensional (Q1D) superconductivity which is derived from the quantum effect of an electron motion in a strong magnetic field. We calculate Tc(H) of both isotropic and anisotropic superconductivity by taking account of the optimal momentum of the Cooper pairs and the effect of higher harmonic terms alo

K. T. Mahanthappa, Sechul Oh

We study both the branching ratio for $b \to s \gamma$ decay and the muon anomalous magnetic moment, $a_{\mu} \equiv (g-2)_{\mu} /2$, in the minimal supersymmetric standard model with gauge-mediated supersymmetry breaking. Combining new experimental data on $a_{\mu}$ and the branching ratio for $b \to s \gamma$, useful limits on the parameter space of these

S. A. Yost, J. J. Bock, M. Kawada, A. E. Lange

We present a search for near-infrared (3.5-5 micron) emission from baryonic dark matter in the form of low-mass stars and/or brown dwarfs in the halo of the nearby edge-on spiral galaxy NGC 5907. The observations were made using a 256 by 256 InSb array with a pixel scale of 17" at the focus of a liquid-helium-cooled telescope carried above the Earth's atmosp

Dennis Zaritsky

We present an analysis of line-of-sight extinction measurements obtained using data from the Magellanic Clouds Photometric Survey, which provides 4-filter photometry for millions of stars in the Large Magellanic Cloud. We find that visual extinctions are typically larger by several tenths of a magnitude for stars with effective temperatures > 12000 K, than f

William Graham

We prove a conjecture of Dale Peterson on positivity in the multiplication in the T-equivariant cohomology of the flag variety. The theorem follows from a more general positivity result about the equivariant cohomology of varieties with actions of a solvable group with finitely many orbits. This more general result is an equivariant version of a theorem of K

Keith R. Dienes, Emilian Dudas, Tony Gherghetta

It has recently been proposed that gravity-localized compactifications can generate the required gauge hierarchy without the need for hierarchically large extra spacetime dimensions. In this paper, we show that gauge coupling unification arises naturally in such scenarios as a result of the anomaly induced by the rescaling of the wavefunctions of the brane f

S. J. Childs

Criteria for the incipient motion of a rigid body initially resting on a rigid surface are formulated from first principles in this work. A modified Coulomb friction model and an associated distribution of reaction forces are proposed. There exists a surprisingly large category of general motions, however, which subscribe to a more conventional analysis; an

L. Zekri, R. Bouamrane, N. Zekri, F. Brouers

We study in this paper the localization of light and the dielectric properties of thin metal-dielectric composites at the percolation threshold and around a resonant frequency where the conductivities of the two components are of the same order. In particular, the effect of the loss in metallic components are examined. To this end, such systems are modelized

J. O. Burns, C. Loken, K. Roettiger, E. Rizza

New adaptive mesh refinement N-body + hydrodynamics numerical simulations are used to illustrate the complex and changing cluster environments in which many radio galaxies live and evolve. Groups and clusters of galaxies form at the intersections of filaments where they continue to accrete gas and dark matter to the present day. The accretion process produce

Gerald Kaiser

An extension of potential theory in R^n is obtained by continuing the Euclidean distance function holomorphically to C^n. The resulting Newtonian potential is generated by an extended source distribution D(z) in C^n whose restriction to R^n is the delta function. This provides a natural model for extended particles in physics. In C^n, interpreted as complex

S. J. Childs

A class of A.L.E. time discretisations which inherit key energetic properties (nonlinear dissipation in the absence of forcing and long-term stability under conditions of time dependent loading), irrespective of the time increment employed, is established in this work. These properties are intrinsic to real flows and the conventional Navier-Stokes equations.

Russell Lyons

We survey known results about phase transitions in various models of statistical physics when the underlying space is a nonamenable graph. Most attention is devoted to transitive graphs and trees.

O. Brein, W. Hollik

The production of pairs of charged Higgs bosons as predicted by the minimal supersymmetric standard model (MSSM) via the gluon fusion mechanism is investigated. The amplitudes at the leading one-loop order for the parton process gg -> H+ H- are calculated with the complete set of MSSM particles. Numerical results are presented for the cross section of the in

Gavriel Segre

Paper erroneously re-submitted as duplicte. Readers should look at math-ph/9909004.

L. Piro, A. De Rosa, M. Dadina, F. Nicastro

We will present some results on the broad--band observations of BeppoSAX of the bright Seyfert galaxies NGC 4151 and NGC 5548.

John L. Friedman, Keith H. Lockitch

A brief review of the stability of rotating relativistic stars is followed by a more detailed discussion of recent work on an instability of r-modes, modes of rotating stars that have axial parity in the slow-rotation limit. These modes may dominate the spin-down of neutron stars that are rapidly rotating at birth, and the gravitational waves they emit may b

M. B. Gay Ducati, V. P. Gonçalves

The AGL equation includes all multiple pomeron exchanges in the double logarithmic approximation (DLA) limit, leading to an unitarized gluon distribution in the small x regime. This equation was originally obtained using the Glauber-Mueller approach. We demonstrate in this paper that the AGL equation and, consequently, the GLR equation, can also be obtained

Alan Adolphson, Steven Sperber

We discuss exponential sums on affine space from the point of view of Dwork's p-adic cohomology theory

Thomas H. Otway

We consider maps between Riemannian manifolds in which the map is a stationary point of the nonlinear Hodge energy. The variational equations of this functional form a quasilinear, nondiagonal, nonuniformly elliptic system which models certain kinds of compressible flow. Conditions are found under which singular sets of prescribed dimension cannot occur. Var

H. Schulz

The Schroedinger functional treatment of 2+1 D Yang-Mills theory (related to the magnetic mass problem of 4D hot gluons) is recapitulated by following Karabali, Kim and Nair in Nucl. Phys. B 524 (1998) 661 (first half). The notes include the Hermitean WZW model and end up with the lowest eigenvalue (mass gap) of the functional kinetic energy. Let calculation

Hae-Young Kee

We study the spin dynamics in a p-wave superconductor at the nesting vector associated with $\alpha$ and $\beta$ bands in Sr$_2$RuO$_4$. We find a collective mode at the nesting vector in the superconducting phase identified as the odd-parity pairing state which breaks time reversal symmetry. This mode in the spin channel only exists in the p-wave supercondu

Xiangdong Ji, Chung-Wen Kao, Jonathan Osborne

We calculate the forward spin-dependent photon-nucleon Compton amplitude as a function of photon energy at the next-to-leading (${\cal O}(p^4)$) order in chiral perturbation theory, from which we extract the contribution to nucleon spin polarizability. The result shows a large correction to the leading order contribution.

M. V. Chizhov, D. P. Kirilova

In this article we discuss lepton asymmetry effect on BBN with neutrino oscillations. We argue that asymmetry much smaller than 0.01, although not big enough to influence directly the nucleosynthesis kinetics, can effect considerably BBN indirectly via neutrino oscillations. Namely, it distorts neutrino spectrum and changes neutrino density evolution and the

C. A. Stafford, J. Burki, D. Baeriswyl

In a recent Letter, Nakamura et al. [Phys. Rev. Lett. 82, 1538 (1999)] described first principles calculations for a breaking Na nanocontact. Their system consists of a periodic one-dimensional array of supercells, each of which contains 39 Na atoms, originally forming a straight, crystalline wire with a length of 6 atoms. The system is elongated by increasi

G. N. Katomeris, S. N. Evangelou

We examine the validity of the recently proposed semi-Poisson level spacing distribution function P(S), which characterizes `critical quantum chaos', in 2D disordered systems with spin-orbit coupling. At the Anderson transition we show that the semi-Poisson P(S) can describe closely the critical distribution obtained with averaged boundary conditions, over D

R. J. Finkelstein

In non-Abelian field theories with q-symmetry groups the massive particles have a non-local interpretation with a stringlike spectrum. It is shown that a massless vector similarly acquires a tower of masses by spontaneous symmetry breaking.

L. Civale, A. V. Silhanek, J. R. Thompson, K. J. Song

Studies of single crystal YNi2B2C have revealed a four-fold anisotropy of the equilibrium magnetization in the square crystallographic basal plane. This pi/2 periodicity occurs deep in the superconductive mixed state. In this crystal symmetry, an ordinary superconductive mass anisotropy (as in usual London theory) allows only a constant, isotropic response.

Thomas P. Kling, Ezra T. Newman, Alejandro Perez

We develop an iterative approach to gravitational lensing theory based on approximate solutions of the null geodesic equations. The approach can be employed in any space-time which is ``close'' to a space-time in which the null geodesic equations can be completely integrated, such as Minkowski space-time, Robertson-Walker cosmologies, or Schwarzschild-Kerr g

Alejandra Kandus, Esteban A. Calzetta, Francisco D. Mazzitelli, Carlos E. M. Wagner

We study the generation of primordial magnetic fields, coherent over cosmologically interesting scales, by gravitational creation of charged scalar particles during the reheating period. We show that magnetic fields consistent with those detected by observation may obtained if the particle mean life \tau_s is in the range 10^{-14} sec \leq \tau_s \leq 10{-7}

A. M. Yafyasov, I. M. Ivankiv, V. B. Bogevolnov

A new method of self-consistent quantum calculation of the density of the space charge near the surface of a crystal is carried out for the semiconductor with nonparabolic (Kane) dispersion law of bands. The remarkable feature is the solution of the Schroedinger equation for electrons and holes in the energy range, including both bound energy states and stat

S. Catani, M. Grazzini

We study the infrared behaviour of tree-level QCD amplitudes and we derive infrared-factorization formulae that are valid at any perturbative order. We explicitly compute all the universal infrared factors that control the singularities in the various soft and/or collinear limits at O(as^2).

P. Thorngren Engblom, H. O. Meyer, J. T. Balewski, W. W. Daehnick

The PINTEX facility at the IUCF Cooler ring, dedicated to the study of spin dependence in nucleon-nucleon interactions, has been used to measure polarization observables of the reaction pp -> pp pi0 at beam energies between 325 and 400 MeV. The stored polarized proton beam had spin projections both in the longitudinal and the transverse directions with respe

R. D'hulst, G. J. Rodgers

An exact solution is presented to a model that mimics the crowding effect in financial markets which arises when groups of agents share information. We show that the size distribution of groups of agents has a power law tail with an exponential cut-off. As the size of these groups determines the supply and demand balance, this implies heavy tails in the dist

S'i. Yoshida, Y. Eriguchi

By using the Cowling approximation, quasi-radial modes of rotating general relativistic stars are computed along equilibrium sequences from non-rotating to maximally rotating models. The eigenfrequencies of these modes are decreasing functions of the rotational frequency. The eigenfrequency curve of each mode as a function of the rotational frequency has dis

Matteo Marsili, Damien Challet, Riccardo Zecchina

We discuss a model of heterogeneous, inductive rational agents inspired by the El Farol Bar problem and the Minority Game. As in markets, agents interact through a collective aggregate variable -- which plays a role similar to price -- whose value is fixed by all of them. Agents follow a simple reinforcement-learning dynamics where the reinforcement, for eac

I. Sarria, J. Osma, E. V. Chulkov, J. M. Pitarke

We report extensive calculations of the imaginary part of the electron self-energy in the vicinity of the (100) and (111) surfaces of Cu. The quasiparticle self-energy is computed by going beyond a free-electron description of the metal surface, either within the GW approximation of many-body theory or with inclusion, within the GW$\Gamma$ approximation, of

Alan M. Nathan

Real Compton Scattering on the proton in the hard scattering regime is investigated. Recent theoretical developments are reviewed. Plans for new experimental studies at Jefferson Laboratory are presented.

Nicola Bartolo, Massimo Pietroni

Scalar fields with inverse power-law effective potentials may provide a negative pressure component to the energy density of the universe today, as required by cosmological observations. In order to be cosmologically relevant today, the scalar field should have a mass $m_\phi = O(10^{-33} {\mathrm eV})$, thus potentially inducing sizable violations of the eq

Julie Fry

A review of existing pre-college science programs for young women in high school is presented,with emphasis on the University of Rochester Pre-College Experience in Physics summer program for 9th and 10th grade high school women (PREP-CMS). A new model for such programs is proposed.

Adam F. Falk

A review is given of recent developments in the physics of flavor. Current constraints on the Cabibbo-Kobayashi-Maskawa matrix are discussed and related to the recent measurements of epsilon'/epsilon, sin(2beta) and K+ -> pi+ nu nubar. A brief review is given of the connection between CP violation in B decays and electroweak baryogenesis. Finally, there is a

B. Biswal, C. Manwart, R. Hilfer, S. Bakke

A quantitative comparison between the experimental microstructure of a sedimentary rock and three theoretical models for the same rock is presented. The microstructure of the rock sample (Fontainebleau sandstone) was obtained by microtomography. Two of the models are stochastic models based on correlation function reconstruction, and one model is based on se

Lorenzo Iorio

The general relativistic Lense-Thirring effect can be measured by inspecting a suitable combination of the orbital residuals of the nodes of LAGEOS and LAGEOS II and the perigee of LAGEOS II. The solid and ocean Earth tides affect the recovery of the parameter by means of which the gravitomagnetic force is accounted for in the combined residuals. Thus an ext

Lorenzo Iorio

A new strategy in deriving the Lense-Thirring effect, in the weak field and slow motion approximation of general relativity, on the orbital elements of a test body in the field of different central rotating sources exhibiting axial symmetry is presented. The approach adopted in the present work, in the case of a perfectly spherical source, leads for all the

R. W. Kuhne

Webb et al. presented preliminary evidence for a time-varying fine-structure constant. We show Teller's formula for this variation to be ruled out within the Einstein-de Sitter universe, however, it is compatible with cosmologies which require a large cosmological constant.

Stephen Hewson

We consider the problem of creating locally supersymmetric theories in signature (10,2). The most natural algebraic starting point is the F-algebra, which is the de Sitter-type (10,2) extension of the super-Poincare algebra. We derive the corresponding geometric group curvatures and evaluate the transformations of the associated gauge fields under the action

J. Hein, P. Boyle, C. T. H. Davies, J. Shigemitsu

We present results for the QCD matrix elements involved in semi-leptonic decays of B-mesons into pseudo scalar heavy light states. The application of NRQCD heavy quarks allows for quark masses around the physical b-quark. We investigate the dependence of the form factors on the external momenta and looked at the mass dependence at zero recoil. For the first

M. H. van Kerkwijk, V. M. Kaspi, A. R. Klemola, S. R. Kulkarni

We report on Keck and Hubble Space Telescope optical observations of the eclipsing binary pulsar system PSR B1718-19, in the direction of the globular cluster NGC 6342. These reveal a faint star ($m_{\rm F702W}=25.21\pm0.07$; Vega system) within the pulsar's 0\farcs5 radius positional error circle. This may be the companion. If it is a main-sequence star in

A. Duncan, E. Eichten, H. Thacker

The computational requirements and dynamics of Monte Carlo simulations of unquenched QCD incorporating the infrared quark eigenmodes (up to $\approx \Lambda_{QCD}$) exactly and UV modes via a loop representation are discussed. The accuracy of such a loop representation is studied for a variety of lattice volumes and quark masses. The method has been successf

Miguel Alcubierre, Gabrielle Allen, Bernd Bruegmann, Edward Seidel

We study the stability properties of the standard ADM formulation of the 3+1 evolution equations of general relativity through linear perturbations of flat spacetime. We focus attention on modes with zero speed of propagation and conjecture that they are responsible for instabilities encountered in numerical evolutions of the ADM formulation. These zero spee

Lars Brink, P. Ramond

After a brief historical survey that emphasizes the role of the algebra obeyed by the Dirac operator, we examine an algebraic Dirac operator associated with Lie algebras and Lie algebra cosets. For symmetric cosets, its ``massless'' solutions display non-relativistic supersymmetry, and can be identified with the massless degrees of freedom of some supersymme

K. S. D. Beach, R. J. Gooding, F. Marsiglio

We critique a Pade analytic continuation method whereby a rational polynomial function is fit to a set of input points by means of a single matrix inversion. This procedure is accomplished to an extremely high accuracy using a novel symbolic computation algorithm. As an example of this method in action we apply it to the problem of determining the spectral f

C. Y. Chen

We reveal that realistic fluids generate microscopic-level discontinuity constantly and the discontinuity spreads out with motion of particles rather rapidly and widely. These things cannot be treated by the standard kinetic equations, and thus the existing fluid theories, macroscopic ones and microscopic ones, need to be revised considerably.

Thomas Gramespacher, Markus Buttiker

We introduce electron-like and hole-like distribution functions, which determine the currents and the fluctuation spectra of the currents measured at a normal-conductor--superconductor hetero-structure. These distribution functions are expressed with the help of newly defined partial densities of states for hetero-structures. Voltage measurements using a wea

B. M. Garraway

We examine an extension to the theory of Gaussian wave packet dynamics in a one-dimensional potential by means of a sequence of time dependent displacement and squeezing transformations. Exact expressions for the quantum dynamics are found, and relationships are explored between the squeezed system, Gaussian wave packet dynamics, the time dependent harmonic

G. Roepstorff, Ch. Vehns

The Clifford action on superspaces is analyzed with a view on generalized Dirac fields taking values in some Clifford supermodule. the stress is here on two principles: complexification and polarisation. For applications in field theory, the underlying vector space may carry either a Euclidean or a Minkowskian structure.

J. Wuttke, M. Ohl, M. Goldammer, S. Roth

The dynamic susceptibility of propylene carbonate in the moderately viscous regime above $T_{\rm c}$ is reinvestigated by incoherent neutron and depolarised light scattering, and compared to dielectric loss and solvation response. Depending on the strength of $\alpha$ relaxation, a more or less extended $\beta$ scaling regime is found. Mode-coupling fits yie

Jouko Mickelsson, Simon Scott

Using properties of the determinant line bundle for a family of elliptic boundary value problems, we explain how the Fock space functor defines an axiomatic quantum field theory which formally models the Fermionic path integral. The 'sewing axiom' of the theory arises as an algebraic pasting law for the determinant of the Dirac operator. We show how represen

Barbara Clerbaux

A compilation of H1 and ZEUS cross section measurements for elastic vector meson production is presented as a function of the scale $K^2 = (Q^2+M_V^2)/4$, where Q^2 is the exchanged photon virtuality and M_V is the mass of the vector meson. The ratio of longitudinal to transverse cross sections R = $\sigma_L/\sigma_T$ is presented as a function of Q^2/M^2_V.

Francesca Rosati

Recent data point in the direction of a $\Lambda$ dominated universe. We briefly review ``Quintessence'' as a model for a dynamical cosmological term and analyse the role of Susy QCD as a possible particle physics candidate. The multiscalar content of the theory is fully taken into account and interaction with other cosmological fields is discussed. Finally,

Al. H. Raduta, Ad. R. Raduta

A modified version is in preparation.

Oscar E. Ramírez del Prado

In this paper a calculation for the diffractive structure functions $F_{L}^{D(4)}$ and $F_{T}^{D(4)}$ using an eikonal approximation is presented. A modified version of the model of the stochastic vacuum that includes an energy dependence is used to calculate the scattering amplitude of two Wilson loops which in our approach describe the color dipole interac

Al. H. Raduta, Ad. R. Raduta

The microcanonical multifragmentation model from [Al. H. Raduta and Ad. R. Raduta, Phys. Rev. C 55, 1344 (1997); 56, 2059 (1997); 59, 323 (1999)] is refined and improved by taking into account the experimental discrete levels for fragments with $A \le 6$ and by including the stage of sequential decay of the primary excited fragments. The caloric curve is ree

Gunther Cornelissen

Let G be the separable Galois group of a finite field F of characteristic p, and X/F an imaginary hyperelliptic curve such that G acts transitively on its set W(X) of Weierstrass points. The existence of a G-invariant 2-torsion point on the Jacobian J(X) of X depends only on the parity of |W(X)|, but for large enough |F|, there exist two such curves X and X'

Stephen W. Pierson, Oriol T. Valls

The flux lattice melting temperature in optimally doped YBCO has been shown to be very close to that of the onset of fluctuations around H_{c2}(T). Here, we present a theoretical argument in support of the idea that this occurs because the increased strength of the fluctuations as a function of magnetic field pushes away the first order flux lattice melting

Johannes Hager, Lothar Sch"afer

In recent large scale Monte-Carlo simulations of various models of Theta-point polymers in three dimensions Grassberger and Hegger found logarithmic corrections to mean field theory with amplitudes much larger than the universal amplitudes of the leading logarithmic corrections calculated by Duplantier in the framework of tricritical O(n) field theory. To re

Masafumi Seriu

In spacetime physics, we frequently need to consider a set of all spaces (`universes') as a whole. In particular, the concept of `closeness' between spaces is essential. However, there has been no established mathematical theory so far which deals with a space of spaces in a suitable manner for spacetime physics. Based on the scheme of the spectral represent

Stephen W. Pierson, Mark Friesen

The value of the dynamic critical exponent z has been studied for experimental two-dimensional superconducting and Josephson Junction array systems in zero magnetic field via the Fisher-Fisher-Huse dynamic scaling analysis. We found z~5.6, a relatively large value indicative of non-diffusive dynamics. We extend this work here to simulational I-V curves that

M. N. Achasov, S. E. Baru, A. V. Bozhenok, A. D. Bukin

Results of the SND experiment at the VEPP-2M e+ e- collider on the QED processes e+ e- --> e+ e- gamma and e+ e- --> e+ e- gamma gamma with production at large angles are presented. Energy and angular distributions of the final particles were studied. No deviations from QED with an accuracy of 3.8% for the first process and 10.3% for the second were found.

Fumiharu Kato

In this article we discuss a certain p-adic analogue of classical Schwarzian triangle groups, an analogue which is related to Mumford's uniformization of p-adic analytic curves. p-adic Schwarzian triangle groups are defined to be the Galois groups of analytic coverings over projective line with precisely 3 branch points. We say that a p-adic triangle group i

Gunther Cornelissen, Fumiharu Kato, Aristeides Kontogeorgis

A Mumford curve of genus g (>1) over a non-archimedean valued field k of positive characteristic has at most max{12(g-1), 2 g^(1/2) (g^(1/2)+1)^2} automorphisms. This bound is sharp in the sense that there exist Mumford curves of arbitrary high genus that attain it (they are fibre products of suitable Artin-Schreier curves). The proof provides (via its actio

Parthapratim Biswas, Prabhat K Thakur

Electron localization property of a random chain changing under the influence of a constant electric field has been studied. We have adopted the multifractal scaling formalism to explore the possible localization behavior in the system. We observe that the possible localization behavior with the increase of electric field is not systematic and shows strong i

A. Dedes, S. Moretti

If the soft Supersymmetry (SUSY) breaking masses and couplings are complex and cancelations do take place in the SUSY induced contributions to the fermionic Electric Dipole Moments (EDMs), then the CP-violating soft phases can drastically modify much of the known phenomenological pattern of the Minimal Supersymmetric Standard Model (MSSM). In particular, the

Christoph J. Halboth, Walter Metzner

Salmhofer [Commun. Math. Phys. 194, 249 (1998)] has recently developed a new renormalization group method for interacting Fermi systems, where the complete flow from the bare action of a microscopic model to the effective low-energy action, as a function of a continuously decreasing infrared cutoff, is given by a differential flow equation which is local in

George Chechelashvili, George Jorjadze

It is shown that the model of 2d dilaton gravity is equivalent to the dynamical system of massless particles in the Liouville field.

Jorge Melnick, Roberto Terlevich, Elena Terlevich

We re-investigated the use of the Hubble diagram to measure the cosmological constant ($\Lambda$) and the mass density of the Universe ($\Omega_M$). We find an important focusing effect in $\Lambda$ for redshifts about 3. This effect implies that the apparent magnitude of a standard candle at redshifts z=2-3 has almost no dependence on $\Lambda$ for $\Omega_

Claudia Glasman

Measurements of inclusive jet, dijet and three-jet cross sections in photon-proton interactions are presented. These measurements provide new tests of QCD, constrain the parton densities of the photon, and allow searches for new physics. Measurements of the mean subjet multiplicity are reported and used to test the differences between quark and gluon jets.

Tomoya Isoshima, Mikio Nakahara, Tetsuo Ohmi, Kazushige Machida

It is shown theoretically that a persistent current can be continuously created in a Bose-Einstein condensate (BEC) of alkali atoms confined in a multiply connected region by making use of a spin-degree of freedom of the order parameter of a BEC. We demonstrate that this persistent current is easily transformed into a vortex. Relaxation processes of these BE

J. E. Pesce, C. M. Urry, M. O'Dowd, R. Scarpa

We analyze images of BL Lacertae objects obtained with the {\it Hubble Space Telescope} WFPC2 and the F814W filter. The nine objects cover a redshift range of 0.19 to 0.997. The relatively deep images are sufficient to detect galaxies at least one magnitude below M$^{*}_{I}$ (--21.4) and in most cases to three magnitudes below M$^{*}$. Galaxy enhancement ove

Agata Olariu

93 items of Neolithic copper from National Museum of History from Bucharest, with the provenance from Moldavia region have been analyzed by neutron activation analysis. The results of the analysis provide the values of the concentrations for the series of the determined elements: Au, Ag, As, Cr, Co, Fe, Hg, Ni, Sb, Se, Sn and Zn.

M. A. Hendry, S. Rauzy

We obtain a robust, non-parametric, estimate of the Hubble constant from galaxy linear diameters calibrated using HST Cepheid distances. Our method is independent of the parametric form of the diameter function and the spatial distribution of galaxies and is insensitive to Malmquist bias. We include information on the galaxy rotation velocities; unlike Tully

N. Straumann

After a short history of the $\Lambda$-term it is explained why the (effective) cosmological constant is expected to obtain contributions from short-distance-physics, corresponding to an energy scale of at least 100 GeV. The actual tiny value of the cosmological constant in any natural scale of units represents, therefore, one of the deepest mysteries of pre

H. Herndl, R. Hofinger, J. Jank, H. Oberhummer

The reaction rates of neutron capture reactions on light nuclei are important for reliably simulating nucleosynthesis in a variety of stellar scenarios. Neutron capture reaction rates on neutron-rich C-, N-, and O-isotopes are calculated in the framework of a hybrid compound and direct capture model. The results are tabulated and compared with the results of

M. V. Cheremisin

The standard ohmic measurements by means of two extra leads contain an additional thermal correction to resistance. The current results in heating(cooling) at first(second) sample contact due to Peltier effect. The contacts temperatures are different. The measured voltage is the sum of the ohmic voltage swing and Peltier effect induced thermopower which is l

D. Becirevic, Ph. Boucaud, J. P. Leroy, J. Micheli

We study the UV-scaling of the flavorless gluon propagator in the Landau gauge in an energy window up to 9 GeV. Dominant hypercubic lattice artifacts are eliminated. A large set of renormalization schemes is used to test asymptotic scaling. We compare with our results obtained directly from the triple gluon vertex. We end-up with \Lambda_{\bar{\rm{MS}}} = 31

Carmen Morales, Joaquin Trapero, Jose F. Gomez, Alvaro Gimenez

We present the far ultraviolet spectrum of alpha Virginis taken with EURD spectrograph on-board MINISAT-01. The spectral range covered is from ~900 to 1080 A with 5 A spectral resolution. We have fitted Kurucz models to IUE spectra of alpha Vir and compared the extension of the model to our wavelengths with EURD data. This comparison shows that EURD fluxes a

J. Hwang, H. Noh

We derive power spectra of the scalar- and tensor-type structures generated in an inflation model based on a massive non-minimally coupled scalar field with the strong coupling assumption. We make analyses in both the original-frame and the conformally transformed Einstein-frame. We derive contributions of both structures to the anisotropy of the cosmic micr

N. Manojlovic, A. Mikovic

We examine the reduced phase space of the Bianchi VII_0 cosmological model, including the moduli sector. We show that the dynamics of the relevant sector of local degrees of freedom is given by a Painleve III equation. We then obtain a zero-curvature representation of this Painleve III equation by applying the Belinskii-Zakharov method to the Bianchi VII_0 m

Sanghyeon Chang, Shiro Tazawa, Masahiro Yamaguchi

A simple axion model is proposed in the scenario of large extra dimensions where gravity scale is as low as 1 TeV. To obtain an intermediate-scale decay constant of the axion, the axion is assumed to live in a sub-spacetime (brane) of the whole bulk. In this model there appear Kaluza-Klein modes of the axion which have stronger interaction than those of the

C. Wetterich

In a gauge-fixed language gluon-meson duality can be described as the Higgs mechanism for ``spontaneous symmetry breaking'' of color. We present a mean field computation which suggests that this phenomenon is plausible in QCD. One obtains realistic masses of the light mesons and baryons.

M. Spurio

We present the measurement of the the flux and angular distribution of atmospheric muon neutrinos using the MACRO detector. Three different event topologies are detected in two different energy ranges. High energy neutrinos (E~80 GeV) via the identification of upward throughgoing muons. Lower energy neutrinos (E~ 4 GeV) via the upgoing stopping and partially

T. G. Kovacs

We use an optimised clover action to study spectroscopy on an instanton ensemble reconstructed from smoothed Monte Carlo configurations. Due to the better chirality of the clover action, the artificial configurations show a marked difference from the free field behaviour obtained with the Wilson action. They however still fail to reproduce the physics observ

F. T. Arecchi, J. Bragard, L. M. Castellano

As an atomic Bose Einstein condensate (BEC) is coupled to a source of uncondensed atoms at the same temperature and to a sink (extraction towards an atom laser) the idealized description in terms of a Gross-Pitaevsky equation (GP) no longer holds. Under suitable physical assumptions we show that the dissipative BEC obeys a Complex Ginzburg Landau equation (C

S. Banerjee, G. R. Kumar, D. Mathur

CS$_2$ is identified as a molecule for which distinction can be made between dynamic and geometric alignment induced by intense laser fields. Measured anisotropic angular distributions of fragment ions arise from (i) dynamic alignment of the S-C-S axes along the laser polarization vector for 35-ps laser pulses and (ii) geometric alignment due to an angle-dep

V. N. Bogomolov

It is shown that the rapid increase of the superconducting transition temperature $T_c$ of sulphur with increasing pressure above 93 GPa does not contradict with some hypothetical ``electronic'' mechanism of superconductivity with participation of the electron interaction energy fluctuations. Such ``electronic'' mechanism is supposed to be intrinsic property

Sara Blom

We have studied the force in mesoscopic wires in the presence of an external magnetic field along the wire using a free electron model. We show that the applied magnetic field can be used to affect the force in the wire. The magnetic field breaks the degeneracy of the eigenenergies of the conduction modes, resulting in more structure in the force as a functi

R. Mélin

Andreev reflection in ferromagnet-superconductor junctions is derived in a regime in which Zeeman splitting dominates the response of the superconductor to an applied magnetic field. Spin-up and spin-down Andreev reflections are shown to be resolved as voltage is increased. In the metallic limit, the transition from Andreev to tunnel conductivity in the spin