February 2001 arXiv papers — page 8

Joshua S. Bloom, Dale A. Frail, Re'em Sari

The fluences of gamma-ray bursts (GRBs) are measured with a variety of instruments in different detector energy ranges. A detailed comparison of the implied energy releases of the GRB sample requires, then, an accurate accounting of this diversity in fluence measurements which properly corrects for the redshifting of GRB spectra. Here, we develop a methodolo

T. Fang, H. L. Marshall, G. L. Bryan, C. R. Canizares

We report the first high-resolution X-ray spectra of two high-redshift quasars, S5 0836+710 and PKS 2149-306, obtained with the Chandra High Energy Transmission Grating Spectrometer (HETGS). The primary goal of this observation is to use the high spectral resolving power of the HETGS to detect X-ray absorption produced by a hot intergalactic medium. The cont

B. Santiago, S. Beaulieu, R. Johnson, G. Gilmore

We show the results of deep V and I HST photometry of 6 rich star clusters in the Large Magellanic Cloud with different ages and metallicities. The number of stars with measured magnitudes in each cluster varies from about 3000 to 10000. We build stellar density and surface brightness profiles for the clusters and extract half-light radii and other structura

Henk Hoekstra

We quantify the uncertainty in weak lensing mass estimates of clusters of galaxies, caused by distant (uncorrelated) large scale structure along the line of sight. We find that the effect is fairly small for deep observations (20<R<26) of massive clusters (sigma=1000 km/s) at intermediate redshifts, where the bulk of the sources are at high redshifts compare

R. Ragazzoni, E. Cappellaro, S. Benetti, M. Turatto

Long-slit echellograms of the high excitation planetary nebula NGC1501, reduced according to the methodology developed by Sabbadin et al. (2000a, b), allowed us to obtain the ``true&#39;&#39; distribution of the ionized gas in the eight nebular slices covered by the spectroscopic slit. A 3-D rendering procedure is described and applied, which assembles the t

R. Overzier, H. Rottgering, J. Kurk, C. De Breuck

In this contribution we will present deep VLT spectroscopy observations of the giant emission line halo around the z=2.49 radio galaxy MRC 2104-242. The morphology of the halo is dominated by two spatially resolved regions. Lya is extended by >12&#34; along the radio axis, C IV and He II are extended by ~8&#34;. The overall spectrum is typical for that of hi

P. Goldoni, A. Goldwurm, P. Laurent, M. Casse&#39;

Cluster of galaxies are the largest concentrations of visible mass in the Universe and therefore a fundamental topic of cosmology and astrophysics. Recent radio, EUV, and X-ray observations suggest that clusters contain large populations of diffuse nonthermal relativistic and/or superthermal particles. These particles may be produced by acceleration in clust

P. Goldoni, A. Goldwurm, P. Laurent, F. Lebrun

We simulate the observation of a bright Nova Musca-like X-ray nova during outburst with INTEGRAL, the next ESA gamma-ray space observatory. We will show how performances of the INTEGRAL instruments allow deep study of X-ray Novae and will evaluate the scientific output that INTEGRAL will provide on this class of transient gamma-ray sources, which are now bel

M. Sasaki, F. Haberl, S. Keller, W. Pietsch

We report pulsations in the X-ray flux of RX J0101.3-7211 in the Small Magellanic Cloud (SMC) with a period of 455+/-2 s in XMM-Newton EPIC-PN data. The X-ray spectrum can be described by a power-law with a photon index of 0.6+/-0.1. Timing analysis of ROSAT PSPC and HRI archival data confirms the pulsations and indicates a period increase of ~5 s since 1993

J. Gorosabel, N. Lund, S. Brandt, N. J. Westergaard

We discuss the INTEGRAL capabilities to detect a high redshift population of gamma-ray bursts (GRBs). First a simple comparison between other past or planned experiments (BATSE, SAX, HETE-2, Romer, Swift) and INTEGRAL instrumentation (IBIS, JEM-X) is shown. After this first view we will be focused on comparing the capabilities of the two most sensitive missi

P. Kervella, V. Coude du Foresto, G. Perrin, M. Schoeller

Cepheids are the primary distance indicators for extragalactic astronomy and therefore are of very high astrophysical interest. Unfortunately, they are rare stars, situated very far from Earth.Though they are supergiants, their typical angular diameter is only a few milliarcseconds, making them very challenging targets even for long-baseline interferometers.

Amancio Friaca, Roberto Terlevich

The analysis of the four-colour maps of galaxies in the Hubble Deep Field has revealed in the sample of 0.4<z<1 early-type field galaxies the existence of ellipticals with a predominantly old coeval stellar population. However, there is another, unexpected, category of HDF early-type galaxies, in which the galaxy core is significantly bluer than the outer re

M. A. D. Machado, F. X. de Araujo, S. Lorenz-Martins

Coude spectroscopic data of a poorly-studied peculiar supergiant, HD327083, are presented. Halpha and Hbeta line profiles have been fitted employing a non-LTE code adequate for spherically expanding atmospheres. Line fits lead to estimates of physical parameters. These parameters suggest that HD327083 may be close to the Luminous Blue Variable phase but it i

The AGN Watch collaboration, M. Santos-Lleo, J. Clavel, B. Schulz

Mid-infrared images of the Seyfert 1 galaxy Mrk 279 obtained with the ISO satellite are presented together with the results of a one-year monitoring campaign of the 2.5-11.7 micron spectrum. Contemporaneous optical photometric and spectrophotometric observations are also presented. The galaxy appears as a point-like source at the resolution of the ISOCAM ins

N. Drory, G. Feulner, R. Bender, C. S. Botzler

The Munich Near-IR Cluster Survey (MUNICS) is a wide-area, medium-deep, photometric survey selected in the K&#39; band. It covers an area of roughly one square degree in the K&#39; and J near-IR pass-bands. The survey area consists of 16 6&#39; x 6&#39; fields targeted at QSOs with redshifts 0.5 < z < 2 and 7 28&#39; x 13&#39; stripes targeted at `random&#39

A. Weiss, M. Flaskamp, V. N. Tsytovich

We investigate the sensitivity of the solar model to changes in the nuclear reaction screening factors. We show that the sound speed profile as determined by helioseismology certainly rules out changes in the screening factors exceeding more than 10%. A slightly improved solar model could be obtained by enhancing screening by about 5% over the Salpeter value

Scott T Kay, Andrew R Liddle, Peter A Thomas

We use the billion-particle Hubble Volume simulations to make statistical predictions for the distribution of galaxy clusters that will be observed by the Planck Surveyor satellite through their effect on the cosmic microwave background -- the Sunyaev-Zel&#39;dovich effect. We utilize the lightcone datasets for both critical density (tauCDM) and flat low-den

Young-Beom Jeon, Seung-Lee Kim, Ho Lee, Myung Gyoon Lee

A new SX Phe star (labelled SXP1) found from $BV$ CCD photometry is the first to be discovered in the globular cluster M15. It is a blue straggler and is located $102\arcsec.8$ north and $285\arcsec.6$ west of the center of M15 \citep{har96}. Mean magnitudes of SXP1 are $<$$B$$>$ = 18$\fm$671 and $<$$V$$>$ = 18$\fm$445. The amplitude of variability of SXP1 i

Jean-Charles Cuillandre, James Lequeux, Ronald J. Allen, Yannick Mellier

Using the Canada-France-Hawaii Telescope we have obtained deep high-resolution CCD images in V and I of a 28&#39;x28&#39; field in the outer disk of M 31 at ~ 116&#39; from the center along the major axis to the south-west, and covering a range of projected galactocentric distance from about 23 to 33 kpc. The field was chosen to correspond with extended HI f

Takahiro Tanaka

There are several works searching for a clue of trans-Planckian physics on the primordial density perturbation spectrum. Here we would like to point out an important aspect which has been overlooked so far. When we consider a model in which the primordial density perturbation spectrum is modified due to trans-Planckian physics, the energy density of fluctuat

Andreas Kabel

In the usual parameter regime of accelerator physics, particle ensembles can be treated as classical. If we approach a regime where $ε_xε_yε_s \approx N_{particles}λ_{Compton}^3\$, however, the granular structure of quantum-mechanical phase space becomes a concern. In particular, we have to consider the Pauli exclusion principle, which will limit the minimum

B. A. McKinney, D. K. Watson

We introduce dimensional perturbation techniques to Bose-Einstein condensation of inhomogeneous alkali gases (BEC). The perturbation parameter is delta=1/kappa, where kappa depends on the effective dimensionality of the condensate and on the angular momentum quantum number. We derive a simple approximation that is more accurate and flexible than the N -> inf

D0 Collaboration, V. M. Abazov

We present a search for charged Higgs bosons in decays of pair-produced top quarks in pbar p collisions at sqrt(s) = 1.8 TeV using 62.2 pb^-1 of data recorded by the D0 detector at the Fermilab Tevatron collider. No evidence is found for signal, and we exclude at 95% confidence most regions of the (M higgs, tan beta) parameter space where the decay t->H b ha

Ernest Ma, Martti Raidal

If the generating mechanism for neutrino mass is to account for both the newly observed muon anomalous magnetic moment as well as the present experimental bounds on lepton flavor nonconservation, then the neutrino mass matrix should be almost degenerate and the underlying physics be observable at future colliders. We illustrate this assertion in two specific

Donald Marolf, Mark Trodden

We consider the collision in 2+1 dimensions of a black hole and a negative tension brane on an orbifold. Because there is no gravitational radiation in 2+1 dimensions, the horizon area shrinks when part of the brane falls through. This provides a potential violation of the generalized second law of thermodynamics. However, tracing the details of the dynamica

Lucien Hardy, David D. Song

We generalise our previous results of universal linear manipulations [Phys. Rev. A63, 032304 (2001)] to investigate three types of nonlinear qubit transformations using measurement and quantum based schemes. Firstly, nonlinear rotations are studied. We rotate different parts of a Bloch sphere in opposite directions about the z-axis. The second transformation

Reginald J. Hill

The hierarchy of exact equations is given that relates two-spatial-point velocity structure functions of arbitrary order with other statistics. Because no assumption is used, the exact statistical equations can apply to any flow for which the Navier-Stokes equations are accurate, and they apply no matter how small the number of samples in the ensemble. The e

S. Ettori

Recent BOOMERANG and MAXIMA-I analyses of the angular power spectrum of the Cosmic Microwave Background put more stringent constraints on the cosmological parameters. I show that these constraints are consistent with the observed baryon budget in clusters of galaxies, allowing any further contribution to this budget from baryons not in stars and not X-ray em

Akhila Raman

This paper examines some of the recent experiments on superluminal propagation. It is well known that Sommerfeld and Brillouin analyzed a rectangular sinusoidal signal propagating through a dispersive medium and derived expressions to describe the precursors and the main signal. In this paper, the impulse response of this dispersive medium is derived as exac

Adam Biernacik, Katarzyna Cieckiewicz, Karol Kolodziej

We analyze the four-fermion reactions e+e- -> 4f containing a single top quark and three other fermions, a possible decay product of the resonant anti-top quark, in the final state. This allows us to estimate the contribution of the nonresonant Feynman graphs and effects related to the off mass shell production and decay of the top quark. We test the sensiti

I. E. Psarobas

A brief report is presented on the effect of viscoelastic losses in a high density contrast sonic band-gap material of close-packed rubber spheres in air. The scattering properties of such a material are computed with an on-shell multiple scattering method, properties which are compared with the lossless case. The existence of an appreciable omnidirectional

Klaus Behrndt, Gabriel Lopes Cardoso, Dieter Lust

We construct four-dimensional domain wall solutions of N=2 gauged supergravity coupled to vector and to hypermultiplets. The gauged supergravity theories that we consider are obtained by performing two types of Abelian gauging. In both cases we find that the behaviour of the scalar fields belonging to the vector multiplets is governed by the so-called attrac

S. R. de Echaniz, Andrew D. Greentree, A. V. Durrant, D. M. Segal

Observations of a doubly driven V system probed to a fourth level in an N configuration are reported. A dressed state analysis is also presented. The expected three-peak spectrum is explored in a cold rubidium sample in a magneto-optic trap. Good agreement is found between the dressed state theory and the experimental spectra once light shifts and uncoupled

Juan Jose Manjarin

In this letter we study the dilatonic corrections to the static gauge potential between heavy sources. These corrections come from the solutions to the the lowest order beta equations. In the energetically favoured branch, the potential obtained is characterised by having a linear confining term, an $L$ independent term and another 1/L piece. This is indicat

Branislav Jurco, Peter Schupp, Julius Wess

The concept of covariant coordinates on noncommutative spaces leads directly to gauge theories with generalized noncommutative gauge fields of the type that arises in string theory with background B-fields. The theory is naturally expressed in terms of cochains in an appropriate cohomology; we discuss how it fits into the framework of projective modules. The

Peter Minkowski

The road towards unification of elementary interactions is thought to start on the solid ground of a universal local gauge principle. I discuss the different types of bosonic gauge symmetries in gravitational and nongravitational (standard model) interactions and their extensions both fermionic, bosonic and with respect to space-time dimensions. The apparent

C. Wetterich

We explore the possibility that QCD may undergo a phase transition as a function of the strange quark mass. This would hint towards models with ``spontaneous color symmetry breaking&#39;&#39; in the vacuum. For two light quark flavors we classify possible colored quark-antiquark, diquark and gluon condensates that are compatible with a spectrum of integer ch

I. M. Gioia, J. P. Henry, C. R. Mullis, W. Voges

The deepest region of the ROSAT All-Sky Survey, at the North Ecliptic Pole, has been studied to produce a complete and unbiased X-ray selected sample of clusters of galaxies. This sample is used to investigate the nature of cluster evolution and explore potential implications for large-scale structure models. The survey is 99.6% optically identified. Spectro

J. Winicour

I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to current 3D black codes that simulate binary black holes. A prime application of characteristic evolution is Cauchy-characteristic matching, which is also reviewe

Konstantin G. Zloshchastiev

We consider the D-dimensional massive dilaton gravity coupled to Maxwell and antisymmetric tensor fields (EMATD). We derive the full separability of this theory in static case. This discloses the core structure of the theory and yields the simple procedure of how to generate integrability classes. As an example we take a certain new class, obtain the two-par

J. Santiago, F. J. Yndurain

We improve the existing calculations of deep inelastic scattering to next to next to leading order in the following manner. First, we use the recently calculated values of the anomalous dimensions for moments with index n=10,12 in ep scattering. Second, we use also recently calculated anomalous dimensions for n=1,3,...,13 for xF3 in neutrino N scattering, to

N. Pirzkal, L. Collodel, T. Erben, R. A. E. Fosbury

Following the second HST servicing mission in 1997 when the STIS instrument was installed and the capability for parallel observations was enhanced, a substantial archive of non-proprietary parallel data has been accumulating. In this paper, we discuss the use of unfiltered STIS imaging data for a project that requires deep observations along as many indepen

Chun Liu, Jeonghyeon Song

The muon- and tau-neutrinos with the mass in the keV range, which are allowed in a low reheating temperature cosmology, can compose the warm dark matter of the universe. A model of four light neutrinos including the keV scale $ν_μ$ and $ν_τ$ is studied, which combines the seesaw mechanism and the Abelian flavor symmetry. The atmospheric neutrino anomaly is d

M. Burkardt, S. K. Seal

We present results from a study of light meson spectra and structure obtained within the framework of light-front QCD formulated on a transverse lattice. We discuss how imposing Lorentz covariance conditions on meson dispersion relations allows determination of parameters in the transverse lattice Hamiltonian. The pion distribution amplitude obtained in this

Holger F. Hofmann, Toshiki Ide, Takayoshi Kobayashi, Akira Furusawa

It is shown that the information losses due to the limited fidelity of continuous variable quantum teleportation are equivalent to the losses induced by a beam splitter of appropriate reflectivity.

Mahn-Soo Choi, Francesco Plastina, Rosario Fazio

We study intrinsic noise of current in a superconducting single-electron transistor, taking into account both coherence effects and Coulomb interaction near a Cooper-pair resonance. Due to this interplay, the statistics of tunneling events deviates from the Poisson distribution and, more important, it shows even-odd asymmetry in the transmitted charge. The z

Zurab Kakushadze, Radu Roiban

We discuss non-conformal gauge theories from type IIB D3-branes embedded in orbifolded space-times. Such theories can be obtained by allowing some non-vanishing logarithmic twisted tadpoles. In certain cases with N=0,1 supersymmetry correlation functions in the planar limit are the same as in the parent N=2 supersymmetric theories. In particular, the effecti

T. Totani, Y. Yoshii, F. Iwamuro, T. Maihara

Deep optical and near-infrared galaxy counts are utilized to estimate the extragalactic background light (EBL) coming from normal galactic light in the universe. Although the slope of number-magnitude relation of the faintest counts is flat enough for the count integration to converge, considerable fraction of EBL from galaxies could still have been missed i

Johann Summhammer

In quantum experiments the acquisition and representation of basic experimental information is governed by the multinomial probability distribution. There exist unique random variables, whose standard deviation becomes asymptotically invariant of physical conditions. Representing all information by means of such random variables gives the quantum mechanical

B. P. Lavrov

Careful re-examination of typical experimental data made it possible to show that the UV continua observed in multi-bubble (MBSL) and single-bubble (SBSL) sonoluminescence spectra have the same physical nature - radiative dissociation of electronically excited hydrogen molecules [and probably hydrides of heavy rare gases like ArH*] due to spontaneous transit

Riccardo A. G. Cinelli, Valentina Tozzini, Vittorio Pellegrini, Fabio Beltram

The coherent dynamics of vibronic wave packets in the green fluorescent protein is reported. At room temperature the non-stationary dynamics following impulsive photoexcitation displays an oscillating optical transmissivity pattern with components at 67 fs (497 cm-1) and 59 fs (593 cm-1). Our results are complemented by ab initio calculations of the vibratio

Thomas S. Levi, David C. Montgomery

We evaluate numerically the velocity field distributions produced by a bounded, two-dimensional fluid model consisting of a collection of parallel ideal line vortices. We sample at many spatial points inside a rigid circular boundary. We focus on ``nearest neighbor&#39;&#39; contributions that result from vortices that fall (randomly) very close to the spati

E. Caurier, K. Langanke, G. Martinez-Pinedo, F. Nowacki

Isotope shifts in the nuclear charge radius of even and odd calcium isotopes are calculated within the nuclear shell model. The model space includes all configurations of nucleons in the $2s, 1d_{3/2}, 1f_{7/2}, {\rm and} ~2p_{3/2}$ orbits. The shell model describes well the energies of the intruder states in Sc and Ca, as well as the energies of the low-lyi

R. M. Davidson, Ron Workman

We compare the effects of several form factor recipes in fits to pseudoscalar meson photoproduction data. The specific examples of pion and kaon photoproduction are used to illustrate how different choices can alter the results of such analyses.

Denis Lacroix, Sakir Ayik, Philippe Chomaz

The giant monopole, dipole and quadrupole responses in $^{40}$Ca, $^{90}$Zr, $^{120}$Sn and $^{208}$Pb are investigated using linear response treatment based on a stochastic one-body transport theory. Effects of the coupling to low-lying surface modes (coherent mechanism) and the incoherent mechanism due to nucleon-nucleon collisions are included beyond the

E. Sauvan, F. M. Marqués, H. W. Wilschut, N. A. Orr

Radiative capture of protons is investigated as a probe of clustering in nuclei far from stability. The first such measurement on a halo nucleus is reported here for the reaction $^6$He(p,$γ$) at 40 MeV. Capture into $^7$Li is observed as the strongest channel. In addition, events have been recorded that may be described by quasi-free capture on a halo neutr

S. E. Derkachov, D. Karakhanyan, R. Kirschner

We derive the integral operator form for the general rational solution of the Yang-Baxter equation with $s\ell(2|1)$ symmetry. Considering the defining relations for the kernel of the R-operator as a system of second order differential equations we observe remarkable reduction to a system of simple first order equations. The obtained kernel of R-operator has

G. Boffetta, A. Celani

We study the statistics of pair dispersion in two-dimensional turbulence. Direct numerical simulations show that the pdf of pair separations is in agreement with the Richardson prediction. The pdf of doubling times follows dimensional scaling and shows a long tail which is the signature of close approaches between particles initially seeded with a large sepa

Satyan L. Devadoss

The real points of the Deligne-Knudsen-Mumford moduli space of marked points on the sphere has a natural tiling by associahedra. We extend this idea to create a moduli space tiled by cyclohedra. We explore the structure of this space, coming from blow-ups of hyperplane arrangements, as well as discuss possibilities of its role in knot theory and mathematical

Michael Coco, M. C. Lammers

We construct Hilbert $C^*$-modules useful for studying Gabor systems and show that they are Banach algebras under pointwise multiplication. For rational $ab<1$ we prove that the set of functions $g \in L^2(R)$ so that $(g,a,b)$ is a Bessel system is an ideal for the Hilbert $C^*$-module given this pointwise algebraic structure. This allows us to give a multi

Leon A. Takhtajan

We study families of quantum field theories of free bosons on a compact Riemann surface of genus g. For the case g > 0 these theories are parameterized by holomorphic line bundles of degree g-1, and for the case g=0 - by smooth closed Jordan curves on the complex plane. In both cases we define a notion of tau-function as a partition function of the theory an

Deepak Parashar

We address the problem of duality between the coloured extension of the quantised algebra of functions on a group and that of its quantised universal enveloping algebra i.e. its dual. In particular, we derive explicitly the algebra dual to the coloured extension of GL_q(2) using the coloured RLL relations and exhibit its Hopf structure. This leads to a colou

John B. Etnyre, Ko Honda

In this note we make several observations concerning symplectic cobordisms. Among other things we show that every contact 3-manifold has infinitely many concave symplectic fillings and that all overtwisted contact 3-manifolds are ``symplectic cobordism equivalent.&#39;&#39;

H. Bueno, C. Tomei

The critical set C of the operator F:H^2_D([0,pi]) -> L^2([0,pi]) defined by F(u)=-u&#39;&#39;+f(u) is studied. Here X:=H^2_D([0,pi]) stands for the set of functions that satisfy the Dirichlet boundary conditions and whose derivatives are in L^2([0,pi]). For generic nonlinearities f, C=\cup C_k decomposes into manifolds of codimension 1 in X. If f&#39;&#39;<

Dmitry Alekseevsky, Andreas Kriegl, Mark Losik, Peter W. Michor

We investigate the rudiments of Riemannian geometry on orbit spaces $M/G$ for isometric proper actions of Lie groups on Riemannian manifolds. Minimal geodesic arcs are length minimising curves in the metric space $M/G$ and they can hit strata which are more singular only at the end points. This is phrased as convexity result. The geodesic spray, viewed as a

Gerard van der Geer, Marcel van der Vlugt

We construct an explicit asymptotically good tower of curves over the field with eight elements. Its limit is 3/2.

D. S. Kalyuzhniy-Verbovetzky

We prove that an arbitrary function, which is holomorphic on some neighbourhood of z=0 in $\mathbb{C}^N$ and vanishes at z=0, whose values are bounded linear operators mapping one separable Hilbert space into another one, can be represented as the transfer function of some multiparametric discrete time-invariant conservative scattering linear system with a K

Jacob Towber

In Weyl&#39;s &#34;The Classical Groups&#34;, he introduces some some remarkable differential operators, which he calls &#34;quasi-compositions&#34; of the polarization operators Dij. In the present paper, an equivalent combinatorial formulation is obtained for these operators, and is then used to obtain explicit formulas for the differentials in certain com

K. Bering

1) We identify new parameter branches for the ultra-local boundary Poisson bracket in d spatial dimension with a (d-1)-dimensional spatial boundary. There exist 2^{r(r-1)/2} r-dimensional parameter branches for each d-box, r-row Young tableau. The already known branch (hep-th/9912017) corresponds to a vertical 1-column, d-box Young tableau. 2) We consider a

Chryssomalis Chryssomalakos

The algebra of the generators of translations in superspace is unstable, in the sense that infinitesimal perturbations of its structure constants lead to non-isomorphic algebras. We show how superspace extensions remedy this situation (after arguing that remedy is indeed needed) and review the benefits reaped in the description of branes of all kinds in the

Mark Raugas

We investigate the quantum volume of D-branes wrapped around cycles of various dimension in Calabi-Yau fourfolds and fivefolds. Examining the cases of the sextic and heptic hypersurface Calabi-Yau varieties, as well as one example in weighted projective space, we find expressions for periods which vanish at the singular point analogous to the conifold point.

L. Da Rold, C. D. Fosco, A. Lopez

We consider a Dirac field in 2+1 dimensions with a domain wall like defect in its mass, minimally coupled to a dynamical Abelian vector field. The mass of the fermionic field is assumed to have just one linear domain wall, which is externally fixed and unaffected by the dynamics. We show that, under some general conditions on the parameters, the localized ze

Hyung Do Kim

We consider Randall-Sundrum(RS) model in generalized gravities and see that the localization of gravity happens in generic situations though its effectiveness depends on the details of the configuration. It is shown that RS picture is robust against quantum gravity corrections ($ϕ\R$) as long as the correction is reasonably small. We extend our consideration

Elso Drigo filho, Regina Maria Ricotta

The association of the variational method with supersymmetric quantum mechanics through an ansatz for the superpotential is reviewed and the approximate energy spectra of non-exactly solvable potentials, such like the Hulthen, the Morse and the screened Coulomb potentials, in 3 dimensions, are presented. A sketch of a new exactly shape invariant potential is

Bojan Gornik, Norma Mankoc Borstnik

The proof is presented that the Poincare symmetry determines the equations of motion for massless particles of any spin in 2n-dimensional spaces, which are linear in the momentum.

Klaus Kirsten

This manuscript has been withdrawn by the author. For reasons please contact Klaus Kirsten at klaus@a35.ph.man.ac.uk or kirsten@itp.uni-leipzig.de

M. E. Carrington, Hou Defu, R. Kobes

We study nonlinear response in weakly coupled hot $ϕ^4$ theory. We obtain an expression for a quadratic shear viscous response coefficient using two different formalisms: transport theory and response theory. The transport theory calculation is carried out by assuming a local equilibrium form for the distribution function and expanding in the gradient of the

K. A. Milton, I. L. Solovtsov, O. P. Solovtsova

The method of analytic perturbation theory, which avoids the problem of ghost-pole type singularities and gives a self-consistent description of both spacelike and timelike regions, is applied to describe the &#34;light&#34; Adler function corresponding to the non-strange vector channel of the inclusive decay of the $τ$ lepton. The role of threshold effects

W. Grimus, T. Schwetz

We examine the (3+1)-class of 4-neutrino mass spectra within a rigorous statistical analysis based on the Bayesian approach to probability. The data of the Bugey, CDHS and KARMEN experiments are combined by using a likelihood function. Our statistical approach allows us to incorporate solar and atmospheric neutrino data and also the result of the CHOOZ exper

Guo-Li Wang, Chao-Hsi Chang, Tai-Fu Feng

The radiative corrections to the pure leptonic decay $D_s{\longrightarrow} {\ell}{ν}_{\ell}$ up-to one-loop order is presented. We find the virtual photon loop corrections to $D_s{\longrightarrow} τ{ν}_τ$ is negative and the corresponding branching ratio is larger than $3.51\times 10^{-3}$. Considering the possible experimental resolutions, our prediction of

Bing An Li

An intrinsic form factor has benn found and the slope of the form factor has been predicted.

John P. Costella, Bruce H. J. McKellar, Andrew A. Rawlinson, Gerard J. Stephenson

We review why the Thomas rotation is a crucial facet of special relativity, that is just as fundamental, and just as &#34;unintuitive&#34; and &#34;paradoxical&#34;, as such traditional effects as length contraction, time dilation, and the ambiguity of simultaneity. We show how this phenomenon can be quite naturally introduced and investigated in the context

J. A. Aguilar-Saavedra, T. Riemann

We present a comprehensive analysis of the sensitivity of the TESLA e+ e- collider to top flavour-changing neutral couplings to the Z boson and photon. We study single top production and top decay processes, and we consider the cases without beam polarization, with only e- polarization and with e- and e+ polarization. We show that the use of the latter subst

The DELPHI Collaboration, P. Abreu

An update of the search for sleptons, neutralinos and charginos in the context of scenarios where the lightest supersymmetric particle is the gravitino and the next-to-lightest supersymmetric particle is a slepton, is presented, together with the update of the search for heavy stable charged particles in light gravitino scenarios and Minimal Supersymmetric S

L. C. Garcia de Andrade

A teleparallel Gödel universe is shown to lead to a simple and natural relation between Cartan torsion and the global rotation of the universe.This is straightforward if one uses the formalism of Cartan&#39;s calculus of exterior differential forms.It is possible to place a limit on the global rotation from the knowledge of torsion and the converse is also t

Thomas Filk

For causal graphs we propose a definition of proper time which for small scales is based on the concept of volume, while for large scales the usual definition of length is applied. The scale where the change from &#34;volume&#34; to &#34;length&#34; occurs is related to the size of a dynamical clock and defines a natural cut-off for this type of clock. By ch

V. P. Ruban, D. I. Podolsky

Motion of an ultra-relativistic perfect fluid in space-time with the Kasner metrics is investigated by the Hamiltonian method. It is found that in the limit of small times a tendency takes place to formation of strong inhomogeneities in matter distribution. In the case of slow flows the effect of non-stationary anisotropy on dynamics of sound waves and behav

L. C. Garcia de Andrade

Cosmic strings inside Schwarzschild black holes in teleparallel gravity are considered.Torsion flux inside the black hole is compute like a torsion vortex on a superfluid.Since some components of torsion are singular on Schwarzschild horizon and others remain finite we compute a torsion invariant to decide whether the torsion is singular and where torsion si

Roxana Cocan, Joseph O&#39;Rourke

We prove that, in all dimensions d>=4, every simple open polygonal chain and every tree may be straightened, and every simple closed polygonal chain may be convexified. These reconfigurations can be achieved by algorithms that use polynomial time in the number of vertices, and result in a polynomial number of ``moves.&#39;&#39; These results contrast to thos

Jaechun No, Rajeev Thakur, Dinesh Kaushik, Lori Freitag

Many scientific applications are I/O intensive and generate or access large data sets, spanning hundreds or thousands of &#34;files.&#34; Management, storage, efficient access, and analysis of this data present an extremely challenging task. We have developed a software system, called Scientific Data Manager (SDM), that uses a combination of parallel file I/

Marco Visentin

In this document we propose a new improvement for boosting techniques as proposed in Friedman &#39;99 by the use of non-convex cost functional. The idea is to introduce a correlation term to better deal with forecasting of additive time series. The problem is discussed in a theoretical way to prove the existence of minimizing sequence, and in a numerical way

A. K. Rajagopal, Mogus Mochena, P. J. Lin-Chung

A brief review of theory of ferromagnetism of dilute magnetic semiconductors of the form (A,Mn)B based on the double exchange model is first given. A systematic investigation of the phenomena extending the current theory is outlined. We begin with an investigation of the regions of instability of the nonmagnetic towards the ferromagnetic state of a system of

N. Piovella, M. Gatelli, R. Bonifacio

We extend the semiclassical model of the collective atomic recoil laser (CARL) to include the quantum mechanical description of the center-of-mass motion of the atoms in a Bose-Einstein condensate (BEC). We show that when the average atomic momentum is less than the recoil momentum $\hbar\vec q$, the CARL equations reduce to the Maxwell-Bloch equations for t

P Ormerod, C Mounfield

By scientific standards, the accuracy of short-term economic forecasts has been poor, and shows no sign of improving over time. We form a delay matrix of time-series data on the overall rate of growth of the economy, with lags spanning the period over which any regularity of behaviour is postulated by economists to exist. We use methods of random matrix theo

Veronica I. Marconi, Daniel Dominguez

We study the effect of thermal fluctuations in a fully frustrated Josephson junction array driven by a current I larger than the apparent critical current I_c(T). We calculate numerically the behavior of the chiral order parameter of Z_2 symmetry and the transverse helicity modulus (related to the U(1) symmetry) as a function of temperature. We find that the

Giuseppe Albertini

A two-parameter family of quantum spin ladders with local bilinear and biquadratic interactions is shown to be solvable by a mapping onto fragments of integrable spin 1 chains. The phase diagram, consisting of four phases, and the ground state properties are discussed. In one novel phase, the ground state is made up of plaquette singlets and rung singlets, a

M. Crisan, I. Grosu, D. Bodea

We reply to Belitz and Kirkpatrick comment cond-mat/0102064, on cond-mat/0101392.

Y. Bugoslavsky, G. K. Perkins, X. Qi, L. F. Cohen

The recently-discovered MgB2 super-conductor has a transition temperature Tc approaching 40K, placing it intermediate between the families of low and high temperature super-conductors (LTS and HTS). In practical applications, super-conductors are permeated by quantised magnetic flux vortices, and when a current flows there is dissipation unless the vortices

Albert Toelle

The van der Waals liquid orthoterphenyl has long been used as a model system in the study of the glass transition. Motivated by mode-coupling theory, extensive experiments have been undertaken to monitor the onset of structural relaxation on microscopic time and length scales. Using in particular quasielastic neutron scattering, the decay of density and tagg

S. Lizzit, A. Baraldi, A. Groso, K. Reuter

We have performed high resolution XPS experiments of the Ru(0001) surface, both clean and covered with well-defined amounts of oxygen up to 1 ML coverage. For the clean surface we detected two distinct components in the Ru 3d_{5/2} core level spectra, for which a definite assignment was made using the high resolution Angle-Scan Photoelectron Diffraction appr