December 2000 arXiv papers — page 4

Z. D. Genchev, T. L. Boyadjiev

We perform an analytical and numerical study of the crossover from the Josephson effect to the bulk superconducting flow for two identical one-dimensional superconductors, co-existing with a layer of normal material. A generalized Ginzburg-Landau (GL) model, proposed by S.J. Chapman, Q. Du and M.D. Gunzburger was used in modeling the whole structure. When th

J. P. Halpern, M. Eracleous, R. Mukherjee, E. V. Gotthelf

We recently identified the blazar-like radio source G74.87+1.22 (B2013+370) as the counterpart of the high-energy gamma-ray source 3EG J2016+3657 in the Galactic plane. However, since most blazar identifications of EGRET sources are only probabilistic in quality even at high Galactic latitude, and since there also exists a population of unidentified Galactic

Leonardo Testi

We review recent high spatial resolution millimeter continuum and spectral line observations of (proto-)cluster regions. These observations reveal that the mass distribution of prestellar cores is consistent with the initial mass function for field stars suggesting that the IMF is connected to the molecular clouds structure or the cloud fragmentation process

P. Severgnini, G. Risaliti, A. Marconi, R. Maiolino

We present new, quasi-simultaneous hard X-ray and near-IR spectra of the ultraluminous infrared galaxy IRAS 05189-2524, and discuss them together with archival and literature data. The 1.9 Seyfert nucleus is Compton-thin. The near-IR broad lines are seen in transmission, similarly to the X rays, and the medium along the line of sight has an Av/Nh ratio defin

Andreu Alibes, Javier Labay, Ramon Canal

We have developed a detailed standard chemical evolution model to study the evolution of all the chemical elements up to the iron peak in the solar vicinity. We consider that the Galaxy was formed through two episodes of exponentially decreasing infall, out of extragalactic gas. In a first infall episode, with a duration of $\sim$ 1 Gyr, the halo and the thi

G. Tagliaferri, G. Ghisellini, P. Giommi, A. Celotti

The bright BL Lac object PKS 2005-489 was observed by BeppoSAX on November 1-2, 1998, following an active X-ray state detected by RossiXTE. The source, detected between 0.1 and 200 keV, was in a very high state with a continuum well fitted by a steepening spectrum due to synchrotron emission only. Our X-ray spectrum is the flattest ever observed for this sou

Masayuki Akiyama, Kouji Ohta

The results of K-band-imaging observations of a candidate of an absorbed QSO at z=0.653, AX J131831+3341, are presented. The B-K color of the object is 4.85 mag, which is much redder than optically-selected QSOs. The K-band image shows nuclear and extended components, the same as in the optical V-, R-, and I-band images. The nuclear component (I-K = 4.29 mag

M. Akiyama, K. Ohta, N. Tamura, M. Doi

The results of deep-imaging observations of a candidate of an absorbed QSO at z=0.653, AX J131831+3341, are presented. AX J131831+3341 was found during the course of optical follow-up observations of the ASCA Large Sky Survey, and has an X-ray luminosity of 10^{45} erg s^{-1} (2-10keV), which corresponds to those of QSOs. Its optical spectrum shows no signif

Jeffrey Considine, Leonid A. Levin, David Metcalf

Byzantine Agreement introduced in [Pease, Shostak, Lamport, 80] is a widely used building block of reliable distributed protocols. It simulates broadcast despite the presence of faulty parties within the network, traditionally using only private unicast links. Under such conditions, Byzantine Agreement requires more than 2/3 of the parties to be compliant. [

Leonid A. Levin

The existence of one-way functions is arguably the most important problem in computer theory. The article discusses and refines a number of concepts relevant to this problem. For instance, it gives the first combinatorial complete owf, i.e., a function which is one-way if any function is. There are surprisingly many subtleties in basic definitions. Some of t

Miklos Gyulassy, Ivan Vitev, Xin-Nian Wang

The high $p_{\rm T}>3$ GeV azimuthal asymmetry, $v_2(p_{\rm T})$, in non-central nuclear collisions at RHIC is shown to be a sensitive measure of the initial parton density distribution of the produced quark-gluon plasma. A generalization of the Gyulassy-Levai-Vitev (GLV) non-abelian energy loss formalism including Bjorken 1+1D expansion as well as important

S. S. Avancini, J. R. Marinelli, D. P. Menezes, M. M. Watanabe de Moraes

In this work we investigate the chiral symmetry breaking in the q-deformed version of the NJL Model and its consequent mass generation mechanism . We show that the deformation of the NJL model, in the mean field approximation, may take into account correlations that go beyond the mean field and, in a certain limit, approaches the more realistic lattice calcu

Adel Awad, Andrew Chamblin

We present a menagerie of solutions to the vacuum Einstein equations in six, eight and ten dimensions. These solutions describe spacetimes which are either locally asymptotically adS or locally asymptotically flat, and which have non-trivial topology. We discuss the global structure of these solutions, and their relevance within the context of M-theory.

R. -G. Cai, J. X. Lu, Y. -S. Wu

A V-duality conjecture for noncommutative open string theories (NCOS) that result from decoupling D-branes in Lorentz-boost related backgrounds was put forward recently in hep-th/0006013. The aim of this paper is to test the Galilean nature of this conjecture in the gravity dual setup. We start with an (F, D3) bound state Lorentz-boosted along one D3-brane d

T. Roy Choudhury, R. Srianand, T. Padmanabhan

Following Bi & Davidsen (1997), we perform one dimensional semi analytic simulations along the lines of sight to model the intergalactic medium (IGM). Since this procedure is computationally efficient in probing the parameter space -- and reasonably accurate -- we use it to recover the values of various parameters related to the IGM (for a fixed background c

D. Baleanu, S. Baskal

Second rank non-degenerate Killing tensors for some subclasses of spacetimes admitting parallel null one-planes are investigated. Lichnérowicz radiation conditions are imposed to provide a physical meaning to spacetimes whose metrics are described through their associated second rank Killing tensors. Conditions under which the dual spacetimes retain the same

S. Prunet, R. Teyssier, S. T. Scully, F. R. Bouchet

We report here the first full sky component separation and CMB power spectrum estimation using a Wiener filtering technique on simulated data from the upcoming MAP experiment, set to launch in early 2001. The simulations included contributions from the three dominant astrophysical components expected in the five MAP spectral bands, namely CMB radiation, Gala

A. S. Khrykin, V. F. Boreiko, Yu. G. Budyashov, S. B. Gerasimov

The energy spectrum for high energy $γ$-rays ($E_γ\geq 10$ MeV) from the process $pp \to γγX$ emitted at $90^0$ in the laboratory frame has been measured at an energy below the pion production threshold, namely, at 216 MeV. The resulting photon energy spectrum extracted from $γ-γ$ coincidence events consists of a narrow peak at a photon energy of about 24 Me

Kentaroh Yoshida

We investigate the deconfining phase transition in QCD_4 and QED_4 at finite temperature using a perturbative deformation of topological quantum field theory (TQFT). A modified maximal abelian gauge (MAG) is utilized in the analysis. In this case, we can derive the linear potential studying the 2D theory through Parisi-Sourlas (PS) dimensional reduction. The

Koji Fukao, Yoshihisa Miyamoto

The $α$-process (segmental motion) of thin polystyrene films supported on glass substrate has been investigated in a wider frequency range from 10$^{-3}$ Hz to 10$^4$ Hz using dielectric relaxation spectroscopy and thermal expansion spectroscopy. The relaxation rate of the $α$-process increases with decreasing film thickness at a given temperature above the

Harumichi Nishimura, Masanao Ozawa

Deutsch proposed two sorts of models of quantum computers, quantum Turing machines (QTMs) and quantum circuit families (QCFs). In this paper we explore the computational powers of these models and re-examine the claim of the computational equivalence of these models often made in the literature without detailed investigations. For this purpose, we formulate

Masanao Ozawa, Harumichi Nishimura

Foundations of the notion of quantum Turing machines are investigated. According to Deutsch's formulation, the time evolution of a quantum Turing machine is to be determined by the local transition function. In this paper, the local transition functions are characterized for fully general quantum Turing machines, including multi-tape quantum Turing machi

Boris Grishanin, Victor Zadkov

The potentially attainable information capacity of a radiatively stable lambda-system, viewed as the input of a quantum information channel, is studied. The output of the channel is formed by the states of the photon field with optical excitation frequencies, which are created as a result of Raman pumping. The analysis is based on the notion of coherent info

Koichi Saito, Kazuo Tsushima

Short-range quark-quark correlations are introduced into the quark-meson coupling (QMC) model phenomenologically. We study the effect of the correlations on the structure of the nucleon in dense nuclear matter. With the addition of correlations, the saturation curve for symmetric nuclear matter is much improved at high density.

Ken Kiyono, Nobuko Fuchikami

We carried out a fluid dynamical simulation for a forced dripping faucet system using a new algorithm that was recently developed. The simulation shows that periodic external forcing induces transitions from chaotic to periodic motion and vice versa. We further constructed an improved mass-sprig model for the same system on the basis of data obtained from th

N. Athavan, N. Fröman, M. Lakshmanan

The contour integrals, occurring in the arbitrary-order phase-integral quantization conditions given in a previous paper, are in the first- and third-order approximations expressed in terms of complete elliptic integrals in the case that the charges of the Coulomb centres are equal. The evaluation of the integrals is facilitated by the knowledge of quasiclas

N. Athavan, N. Fröman, M. Lakshmanan

In this paper we take up the quantal two-centre problem where the Coulomb centres have arbitrary positive charges. In analogy with the symmetric case, treated in the second paper of this series of papers, we use the knowledge on the quasiclassical dynamics to express the contour integrals in the first- and third-order approximations of the phase-integral qua

K. Thamilmaran, M. Lakshmanan, K. Murali

A very simple nonlinear parallel nonautonomous LCR circuit with Chua's diode as its only nonlinear element, exhibiting a rich variety of dynamical features, is proposed as a variant of the simplest nonlinear nonautonomous circuit introduced by Murali, Lakshmanan and Chua(MLC). By constructing a two-parameter phase diagram in the $(F-ω)$ plane, correspond

N. Athavan, P. O. Fröman, N. Fröman, M. Lakshmanan

The present paper concerns the derivation of phase-integral quantization conditions for the two-centre Coulomb problem under the assumption that the two Coulomb centres are fixed. With this restriction we treat the general two-centre Coulomb problem according to the phase-integral method, in which one uses an {\it a priori} unspecified {\it base function}. W

O. Benois, R. Esposito, R. Marra

The authors in a previous paper proved the hydrodynamic incompressible limit in $d\ge 3$ for a thermal lattice gas, namely a law of large numbers for the density, velocity field and energy. In this paper the equilibrium fluctuations for this model are studied and a central limit theorem is proved for a suitable modification of the vector fluctuation field $\

A. Gerasimov, A. Kotov

In this paper we continue our study of the fourth order transgression on hyperähler manifolds introduced in the previous paper. We give a local construction for the fourth-order transgression of the Chern character form of an arbitrary vector bundle supplied with a self-dual connection on a four dimensional hyperkähler manifold. The construction is based on

A. Gerasimov, A. Kotov

We propose a generalization of the Hodge $dd_c$-lemma to the case of hyperkähler manifolds. As an application of this result we derive the global construction of the fourth order transgression of the Chern character forms of hyperholomorphic bundles over compact hyperkähler manifolds. At the second part of the paper we consider the fourth order transgression

Goro Hatayama, Atsuo Kuniba, Masato Okado, Taichiro Takagi

For coherent families of crystals of affine Lie algebras of type B^{(1)}_n, D^{(1)}_n, A^{(2)}_{2n} and D^{(2)}_{n+1} we describe the combinatorial R matrix using column insertion algorithms for B,C,D Young tableaux.

Jose Maria Ancochea, Otto Rutwig Campoamor

In this paper we consider the problem of classifying the $(n-5)$-filiform Lie algebras. This is the first index for which infinite parametrized families appear, as can be seen in dimension $7.$ Moreover we obtain large families of characteristic nilpotent Lie algebras with nilpotence index 5 and show that at least for dimension 10 there is a characteristic n

Gilles Pisier

We study the space of functions $ϕ\colon \NN\to \CC$ such that there is a Hilbert space $H$, a power bounded operator $T$ in $B(H)$ and vectors $ξ,η$ in $H$ such that $$ϕ(n) = < T^nξ,η>.$$ This implies that the matrix $(ϕ(i+j))_{i,j\ge 0}$ is a Schur multiplier of $B(\ell_2)$ or equivalently is in the space $(\ell_1 \buildrel {\vee}\over {\otimes} \ell_1)^*$

Giovanni Amelino-Camelia

I propose a general class of space-times whose structure is governed by observer-independent scales of both velocity ($c$) and length (Planck length), and I observe that these space-times can naturally host a modification of FitzGerald-Lorentz contraction such that lengths which in their inertial rest frame are bigger than a &#34;minimum length&#34; are also

Marco A. Diaz, Steve F. King, Douglas A. Ross

We show that radiative corrections to chargino production in electron-positron annihilation with polarized beams can be large especially in the case of right handed electrons. In addition, there is some dependency on the squark masses that allows us to extract information about the squark spectrum from the chargino production.

S. B. Gerasimov

Following the idea of the quark-hadron duality we present, within the constituent quark model approach, the relations between different bremsstrahlung-weihgted integrals of the nucleon resonance photoexcitation cross sections and correlation functions of the quark dipole moments in the nucleon ground state. These functions are of interest for checking detail

V M Khatsymovsky

We find that the continuous matter fields are ill-defined in Regge calculus in the physical 4D theory since the corresponding effective action has infinite terms unremovable by the UV renormalisation procedure. These terms are connected with the singular nature of the curvature distribution in Regge calculus, namely, with the presence in d>2 dimensions of th

Neil J. Gunther

The performance of successful Web-based e-commerce services has all the allure of a roller-coaster ride: accelerated fiscal growth combined with the ever-present danger of running out of server capacity. This chapter presents a case study based on the author&#39;s own capacity planning engagement with one of the hottest e-commerce Web sites in the world. Sev

Arnab Mukherjee, Goundla Srinivas, Biman Bagchi

In order to understand the long known anomalies in the composition dependence of diffusion and viscosity of binary mixtures, we introduce here two new models and carry out extensive molecular dynamic simulations. In these models, the two molecular species (A and B) have the same diameter and mass. In model I the inter-species interaction is more attractive t

T. L. Boyadjiev, M. D. Todorov

The minimal length of ``one-dimensional&#39;&#39; Josephson junctions, in which the specific bound states of the magnetic flux retain their stability is discussed numerically. Thereby, we consider as ``long&#39;&#39; every Josephson junction, in which there exists at least one nontrivial stable distribution of the magnetic flux for fixed values of all the ph

G. Ganbold

The ground-state energy, the effective mass and the number of virtual phonons of the optical large polaron confined strictly in one dimension have been estimated by using the generalized Gaussian approximation. The leading-order terms take care of all Gaussian fluctuations in the system and improve the conventional variational estimates at finite coupling. P

Konstantin Kladko

We propose a scaling theory of 2D metal insulator transition discovered by Kravchenko and coworkers. In this theory conductance/resistance duality is an exact relation. The exponent of the stretched exponential in $σ(T)$ is determined by the temperature dependence of the coherence length. The quantum-chaotic nature of the transition is manifested in the squa

Koji Fukao, Yoshihisa Miyamoto

Dielectric relaxation and thermal expansion spectroscopy were made for thin polystyrene films in order to measure the temperature $T_α$ corresponding to the peak in the loss component of susceptibility due to the $α$-process and the $α$-relaxation time $τ$ as functions of film thickness $d$. While the glass transition temperature $T_{\rm g}$ decreases with d

A. Blanchard, R. Sadat, J. G. Bartlett, M. Le Dour

(abridged) We present a new determination of the local temperature function of X-ray clusters. We use a new sample comprising fifty clusters for which temperature information is now available, making it the largest complete sample of its kind. It is therefore expected to significantly improve the estimation of the temperature distribution function of moderat

Mordecai-Mark Mac Low

I argue that star formation is controlled by supersonic turbulence, drawing for support on a number of 3D hydrodynamical and MHD simulations as well as theoretical arguments. Clustered star formation appears to be a natural result of a lack of turbulent support, while isolated star formation is a signpost of global turbulent support.

S. S. Yazadjiev, T. L. Boyadjiev, M. D. Todorov, P. P. Fiziev

We investigate numerically models of the static spherically symmetric boson-fermion stars in the scalar-tensor theory of gravity with massive dilaton field. The proper mathematical model of such stars is interpreted as a nonlinear two-parametric eigenvalue problem with unknown internal boundary. To solve this problem the Continuous Analogue of Newton Method

Hyesung Kang

Diffusive shock acceleration (DSA) is now widely accepted as the model to explain the production of cosmic rays (CRs) in a wide range of astrophysical environments. Despite initial successes of the theory in explaining the energetics and the spectrum of CRs accelerated by supernova remnants, there still remain some unresolved issues such as particle injectio

Utpal Chattopadhyay, Tarek Ibrahim, D. P. Roy

We estimate the electron and neutron electric dipole moments in the focus point scenario of the minimal SUGRA model corresponding to large sfermion masses and moderate to large $\tanβ$. There is a viable region of moderate fine-tuning in the parameter space, around $\tanβ\simeq 5$, where the experimental limits on these electric dipole moments can be satisfi

Masahito Ueda, Tatsuya Nakajima

We present an operator-algebraic approach to deriving the low-lying quasi-degenerate spectrum of weakly interacting trapped N bosons with total angular momentum \hbar L for the case of small L/N, demonstrating that the lowest-lying excitation spectrum is given by 27 g n_3(n_3-1)/34, where g is the strength of the repulsive contact interaction and n_3 the num

M. Wakamatsu

The recent measurements of azimuthal single spin asymmetries by the HERMES collaboration has opened up new possibility to measure chiral-odd distribution functions through semi-inclusive deep-inelastic scatterings. Here, predictions are given for the twist-2 and twist-3 chiral-odd distribution functions of the nucleon within the framework of the chiral quark

Hiroshi Kori, Yoshiki Kuramoto

The phenomenon of slow switching in populations of globally coupled oscillators is discussed. This characteristic collective dynamics, which was first discovered in a particular class of the phase oscillator model, is a result of the formation of a heteroclinic loop connecting a pair of clustered states of the population. We argue that the same behavior can

Kazunari Shima, Motomu Tsuda

A new gravitational interaction of spin 3/2 Nambu-Goldstone(N-G) fermion is constructed, which gives a new framework for the consistent gravitational coupling of spin 3/2 massless field. The action is invariant under a new global supersymmetry.

C. Bachas, M. Petropoulos

We study D-branes of the ${SL(2,\bR)}$ WZW model, and of its discrete orbifolds. Gluing the currents by group automorphisms leads to three types of D-branes: two-dimensional hyperbolic planes ($H_2$), de Sitter branes (dS$_2$), or anti-de-Sitter branes (AdS$_2$). We explain that the dS$_2$ branes are unphysical, because the electric field on their worldvolum

A. I. Akhiezer, A. A. Isayev, S. V. Peletminsky, A. A. Yatsenko

It is shown that under lowering density or temperature a nucleon Fermi superfluid can undergo a phase transition to a new superfluid state corresponding to superposition of states with singlet-triplet (ST) and triplet-singlet (TS) pairing of nucleons (in spin and isospin spaces). Such states arise as a result of branching from one-gap solution of the self-co

G. A. Sokol

Short history of ideas concerning a possible existence of bound states of the $η$-meson and a nucleus is considered. First experiments at BNL and LAMPF on searching for these states are discussed. Another recent experiment using the photon beam of the 1 GeV electron synchrotron of LPI is described. Possible experiments on studying $η$-mesic nuclei using a pr

Andrei Maimistov

Propagation of the extremely short electromagnetic pulse in non-linear dielectric media without the slowly varying envelope approximation is discussed. The models under consideration take into account both resonant and not-resonant excitations of non-linear medium, and polarisation states of electromagnetic wave. Steady state solutions of the relevant equati

Andrey Maimistov, Elena Kazantseva, Sergei Elyutin

We consider the model of quantum dots interacting with coherent radiation when the relaxation processes may be neglected. The system under investigation consists of two discrete energy levels of the quantum dots in the presence of strong electron-electron Coulomb interaction and the transitions between these levels in response to electromagnetic radiation. B

Andreas Leopold Knutsen

We give necessary and sufficient conditions for a big and nef line bundle L of any degree on a K3 surface or Enriques surface to be k-very ample and k-spanned. Furthermore, we give necessary and sufficient conditions for a spanned and big line bundle on a K3 surface to be birationally k-very ample and birationally k-spanned, and relate these concepts to the

S. Bellucci, E. Ivanov, S. Krivonos

Starting from nonlinear realizations of the partially broken central-charge extended N=4 and N=8 Poincaré supersymmetries in D=4, we derive the superfield equations of N=2 and N=4 Born-Infeld theories. The basic objects are the bosonic Goldstone N=2 and N=4 superfields associated with the central charge generators. By construction, the equations are manifest

M. Galynskii, E. Kuraev, M. Levchuk, V. Telnov

The backward Compton scattering is a basic process at future higher energy photon colliders. To obtain a high probability of e->gamma conversion the density of laser photons in the conversion region should be so high that simultaneous interaction of one electron with several laser photons is possible (nonlinear Compton effect). In this paper a detailed consi

Nikolai Uraltsev

Two topics in heavy quark expansion are discussed. The heavy quark potential in perturbation theory is reviewed in connection to the problem of the heavy quark mass. The nontrivial reason behind the failure of the &#34;potential subtracted&#34; mass in higher orders is elucidated. The heavy quark sum rules are the second subject. The physics behind the new e

Mayumi Aoki

We discuss a rate asymmetry for the radiative $B$-meson decay $B \to X_s γ$ within the framework of the supersymmetric standard model based on N=1 supergravity. This model contains new sources of CP violation. In spite of severe experimental constraints on the electric dipole moment of the neutron, a new CP-violating phase may not be suppressed, leading to a

G. S. Sharov

For the relativistic string with massive ends, the three-string baryon model and other string models of the baryon the small disturbances of well known rotational motions are considered. For the string meson model the two types of these disturbances (quasirotational motions) are obtained. They are oscillatory motions in the form of stationary waves in the ro

Joe Sato, Kazuhiro Tobe

We analyze in detail lepton-flavor violation (LFV) in the charged-lepton sector such as $μ\to e γ$, $τ\to μγ$, $μ\to eee$ and the $μ\to e$ conversion in nuclei, within the framework of supersymmetric models with lopsided Froggatt--Nielsen charges, in which the large mixing in the neutrino sector as well as small mixings in the quark sector can be naturally a

Chongxing Yue, Qingjun Xu, Guoli Liu, Jiantao Li

We study the production and decay of the neutral top-pion $π_{t}^{0}$ predicted by topcolor-assisted technicolor(TC2) theory. Our results show that, except the dominant decay modes $b\bar{b}$, $\bar{t}c$ and $gg$, the $π_{t}^{0}$ can also decay into $γγ$ and $Z γ$ modes. It can be significantly produced at high energy $e^{+}e^{-}$ collider(LC) experiments vi

M. Wakamatsu

An incomparable feature of the chiral quark soliton model as compared with many other effective models like the MIT bag model is that it can give reasonable predictions not only for quark distributions but also for antiquark distributions. This will be exemplified by the argument on the positivity constraint for $\bar{u} (x) + \bar{d} (x)$ as well as the Sof

Masaaki Kobayashi, Tsuneaki Tsuru, Kunio Takamatsu, Shin Ishida

The data on the pi- p --> M0 n, with M0 = pi0 pi0 pi0 or pi0 pi0 eta obtained in the GAMS experiment may be useful to study the sigma(400--700) and a_1^chi (1000), which can be taken as chiral partners of pi and rho, respectively. A preliminary analysis for 3pi0 invariant mass spectra gives a support for the assumed a_1^chi with a mass of 930 MeV and Gamma =

G. Chapline, E. Hohlfeld, R. B. Laughlin, D. I. Santiago

It is proposed that the event horizon of a black hole is a quantum phase transition of the vacuum of space-time analogous to the liquid-vapor critical point of a bose fluid. The equations of classical general relativity remain valid arbitrarily close to the horizon yet fail there through the divergence of a characteristic coherence length. The integrity of g

C. P. Search, P. R. Berman

We present a scheme for determining if the quantum state of a small trapped Bose-Einstein condensate is a state with well defined number of atoms, a Fock state, or a state with a broken U(1) gauge symmetry, a coherent state. The proposal is based on the observation of Ramsey fringes. The population difference observed in a Ramsey fringe experiment will exhib

Y. Lyanda-Geller, S. H. Chun, M. B. Salamon, P. M. Goldbart

The low-temperature Hall resistivity ρ_{xy} of La_{2/3}A_{1/3}MnO_3 single crystals (where A stands for Ca, Pb and Ca, or Sr) can be separated into Ordinary and Anomalous contributions, giving rise to Ordinary and Anomalous Hall effects, respectively. However, no such decomposition is possible near the Curie temperature which, in these systems, is close to m

Ranjini Bandyopadhyay, A. K. Sood

We study the rheology of semi-dilute solutions of the sodium salt of calf-thymus DNA in the linear and nonlinear regimes. The frequency response data can be fitted very well to the hybrid model with two dominant relaxation times $τ_{\circ}$ and $τ_{1}$. The ratio $\frac{τ_{\circ}}{τ_{1}} \sim$ 5 is seen to be fairly constant on changing the temperature from

I. M. Mryglod, R. Folk

Using thermodynamic arguments treatment it is shown that, independently on whether Fisher renormalization changes the critical exponents near a phase transition in a constrained system or not, new corrections to scaling with correction exponents proportional to the specific heat index $α$ appear. Because of the smallness $α$ for the Ising, the XY, and the He

A. Borghardt, D. Karpenko

We show that the free relativistic wave equation which describes the particle without or with rest mass has more than one part of energy spectrum. One part of energy spectrum is beginning with rest energy and it is not limited by above. This part of spectrum is called by us as normal. Another part of energy spectrum is beginning with the zero energy . This p

Mitsuhiro Kawasaki, Takashi Odagaki, Klaus W. Kehr

A random walk model in a one dimensional disordered medium with an oscillatory input current is presented as a generic model of boundary perturbation methods to investigate properties of a transport process in a disordered medium. It is rigorously shown that an admittance which is equal to the Fourier-Laplace transform of the first-passage time distribution

Mitsuhiro Kawasaki

Theoretical analyses of the random energy model with only two states and its extension with a hierarchy of only two levels show that these models reproduce out-of-equilibrium phenomena observed in experiments of glassy materials; the rejuvenation effect (the chaos effect), i.e. the abrupt jump and subsequent relaxation of the out-of-phase susceptibility as i

Tetsuo Ohama, Masahiko Isobe, Yutaka Ueda

The nuclear spin-lattice relaxation rate (1/T1) at the V sites in CaV2O5 was measured. The result was compared with the calculation for the two-leg ladder with the strong-coupling expansion. We found a good agreement on the temperature and magnetic field dependence but a discrepancy between the exchange parameters deduced from 1/T1 and the magnetic susceptib

B. Boroson, T. Kallman, J. M. Blondin, M. P. Owen

We compare the predictions of hydrodynamic models of the LMC X-4 X-ray binary system with observations of UV P Cygni lines with the GHRS and STIS spectrographs on the Hubble Space Telescope. The hydrodynamic model determines density and velocity fields of the stellar wind, wind-compressed disk, accretion stream, Keplerian accretion disk, and accretion disk w

Maulik K. Parikh, Sergey N. Solodukhin

We find explicitly the induced graviton propagator on de Sitter branes embedded in various five-dimensional spacetimes; de Sitter branes in AdS and Minkowski space are particular cases. By studying the structure of the momentum-space propagator, we are able to extract interesting physics, much of which is qualitatively different from that of flat branes. We

Fedor Bogomolov, Yuri Tschinkel

We study abelian subgroups of Galois groups of function fields.

Philip Candelas, Xenia de la Ossa, Fernando Rodriguez-Villegas

We study Calabi-Yau manifolds defined over finite fields. These manifolds have parameters, which now also take values in the field and we compute the number of rational points of the manifold as a function of the parameters. The intriguing result is that it is possible to give explicit expressions for the number of rational points in terms of the periods of

G. L. Cardoso, B. de Wit, J. Käppeli, T. Mohaupt

We discuss explicit examples of BPS solutions in four-dimensional N=2 supergravity with R^2-interactions. We demonstrate how to construct solutions by iteration. Generically, the presence of higher-curvature interactions leads to non-static spacetime line elements. We comment on the existence of horizons for multi-centered solutions.

Murray Moinester

CERN COMPASS can investigate pion-photon interactions, to achieve a unique Primakoff Coulomb physics program, centered on pion polarizability and hybrid meson structure studies. COMPASS uses 100-280 GeV beams (muon, pion) and a virtual photon target, and magnetic spectrometers and calorimeters to measure the complete kinematics of pion-photon reactions. The

N. Dadhich, G. Date

The Zipoy-Voorhees family of static, axisymmetric vacuum solutions forms an interesting family in that it contains the Schwarzschild black hole excepting which all other members have naked singularity. We analyze some properties of the region near singularity by studying a natural family of 2-surfaces. We establish that these have the topology of the 2-spher

J. Chiaverini, K. Yasumura, A. Kapitulnik

Using a nanogram-sized single crystal of BSCCO attached to a microcantilever we demonstrate in a direct way that in magnetic fields nearly parallel to the {\it ab} plane the magnetic field penetrates the sample in the form of Josephson vortices rather than in the form of a tilted vortex lattice. We further investigate the relation between the Josephson vorti

M. Kenzelmann, A. Zheludev, S. Raymond, E. Ressouche

Elastic and inelastic neutron scattering were used to study the ordered phase of the quasi-one-dimensional spin-1/2 antiferromagnet ${\rm BaCu_{2}Si_{2}O_{7}}$. The previously proposed model for the low-temperature magnetic structure was confirmed. Spin wave dispersion along several reciprocal-space directions was measured and inter-chain, as well as in-chai

Guy Hed, Alexander K. Hartmann, Eytan Domany

We study in d=3 dimensions the short range Ising spin glass with Jij=+/-1 couplings at T=0. We show that the overlap distribution is non-trivial in the limit of large system size.

Jung Hoon Han, Qiang-Hua Wang, Dung-Hai Lee

We study the electronic structure of the vortex core in the cuprates using the U(1) slave-boson mean-field wavefunctions and their Gutzwiller projection. We conclude that there exists local orbital antiferromagnetic order in the core near optimal doping. We compare the results with that of BCS theory and analyze the spatial dependence of the local tunneling

D. G. d&#39;Enterria, L. Aphecetche, A. Chbihi, H. Delagrange

The production of nuclear bremsstrahlung photons (E$_γ>$ 30 MeV) has been studied in inclusive and exclusive measurements in four heavy-ion reactions at 60{\it A} MeV. The measured photon spectra, angular distributions and multiplicities indicate that a significant part of the hard-photons are emitted in secondary nucleon-nucleon collisions from a thermally

Nuno Costa Dias, Joao Nuno Prata

We consider the general Wigner function for a particle confined to a finite interval and subject to Dirichlet boundary conditions. We derive the boundary corrections to the &#34;star-genvalue&#34; equation and to the time evolution equation. These corrections can be cast in the form of a boundary potential contributing to the total Hamiltonian which together

S. M. Dorkin, L. P. Kaptari, B. Kaempfer, S. S. Semikh

The deuteron charge - exchange reaction pD->n(pp) for the low values of momentum transfer and small excitation energies of final pp - pair is considered in the framework of Bethe - Salpeter approach. The method of calculation of the observables is developed for the case, when the pp - pair is in $^1S_0$ - state. The methodical numerical calculations of the d

R. G. Vishwakarma

We study the m-z relation for Type Ia supernovae data and the θ-z relation for the updated compact radio sources data in 4 variable Λ- models: Λ\sim S^{-2}, Λ\sim H^2, Λ\sim ρand Λ\sim t^{-2}. It is found that all the models fit the data sets equally well and require non-zero, positive values of Λ. The supernovae data favour an accelerating expansion of the

Heiko Molke, Ulli Wolff

For the family of O(n) invariant nonlinear sigma-models we consider boundary conditions that are periodic up to an O(n) rotation. The helicity modulus is related to the change in free energy under variations of the corresponding angle. It defines a nonperturbative finite volume running coupling similar to the Schr&#34;odinger functional for QCD. For the two-

Jason Maron, Peter Goldreich

We simulate incompressible MHD turbulence in the presence of a strong background magnetic field. Our major conclusions are: 1) MHD turbulence is most conveniently described in terms of counter propagating shear Alfven and slow waves. Shear Alfven waves control the cascade dynamics. Slow waves play a passive role and adopt the spectrum set by the shear Alfven

Daijiro Suematsu

We consider the explanation of both data of the atmospheric neutrino and the solar neutrino by the neutrino mass matrix derived from the mixing of neutrinos and gauginos in the extended MSSM with an extra U(1) gauge symmetry. This scenario directly relates the neutrino mass to supersymmetry. The structure of the mass hierarchy and the mixing is determined on

I. Martin, A. V. Balatsky, J. Zaanen

We argue that the Scanning Tunneling Microscope (STM) images of resonant states generated by doping Zn or Ni impurities into Cu-O planes of BSCCO are the result of quantum interference of the impurity signal coming from several distinct paths. The impurity image seen on the surface is greatly affected by interlayer tunneling matrix elements. We find that the

D. F. Phillips, A. Fleischhauer, A. Mair, R. L. Walsworth

We report an experiment in which a light pulse is decelerated and trapped in a vapor of Rb atoms, stored for a controlled period of time, and then released on demand. We accomplish this storage of light by dynamically reducing the group velocity of the light pulse to zero, so that the coherent excitation of the light is reversibly mapped into a collective Ze

M. Beyer

I present recent results on few-body correlations in nuclear matter at finite temperatures and densities. In particular I focus on the four-body correlations. The alpha-particle is the strongest bound state. The investigation is done based on effective in-medium few-body equations that consistently include self energy corrections and Pauli blocking effects.

Tokuzo Shimada, Kengo Kikuchi

The Globally Coupled Map Lattice (GCML) is one of the basic model of the intelligence activity. We report that, in its so-called turbulent regime, periodic windows of the element maps foliate and systematically control the dynamics of the model. We have found various cluster attractors. In one type of them, the maps split into several almost equally populate