May 2003 arXiv papers — page 20

Vladik Kreinovich

According to modern quantum physics, at the microlevel, the dimension of space-time is at least 11; we only observe 4 dimensions because the others are compactified: the size along each of the other dimensions is much smaller than the macroscale. There is no universally accepted explanation of why exactly 4 dimensions remain at the microscopic level. A natur

T. C. Choy

We fill a gap in the arguments of Boykin et al [American Journal of Physics, Vol 70 No. 4, pp 415-420 (2002)] by not invoking an electric current loop (i.e. magnetic dipole model) to account for the radiation energy loss, since an obvious corollary of their results is that the capacitors should radiate directly even if the connecting wires are shrunk to zero

A. Daniel Boese, Jan M. L. Martin, Nicholas C. Handy

When developing and assessing density functional theory methods, a finite basis set is usually employed. In most cases, however, the issue of basis set dependency is neglected. Here, we assess several basis sets and functionals. In addition, the dependency of the semiempirical fits to a given basis set for a generalised gradient approximation and a hybrid fu

Andrej Vilfan, Thomas Duke

The hair cells of the vertebrate inner ear convert mechanical stimuli to electrical signals. Two adaptation mechanisms are known to modify the ionic current flowing through the transduction channels of the hair bundles: a rapid process involves calcium ions binding to the channels; and a slower adaptation is associated with the movement of myosin motors. We

Antonio Celani, Massimo Cencini, Alain Noullez

We present an efficient and parsimonious algorithm to solve mixed initial/final-value problems. The algorithm optimally limits the memory storage and the computational time requirements: with respect to a simple forward integration, the cost factor is only logarithmic in the number of time-steps. As an example, we discuss the solution of the final-value prob

Alexander V. Kochin

We derive the gas dynamics equations considering changes of velocity distribution function on the scale of a molecule free path. We define the molecule velocity distribution function in a specific form so that only molecule velocities after intermolecular collisions in a chosen fixed volume are taken into account. The obtained equations differ from the well-

Lawrence R. Pratt, Henry S. Ashbaugh

Building on a quasi-chemical formulation of solution theory, this paper proposes a self consistent molecular field theory for packing problems in classical liquids, and tests the theoretical predictions for the excess chemical potential of the hard sphere fluid. Results are given for the self consistent molecular fields obtained, and for the probabilities of

W. Z. Jiang

For the free Fermion gas at thermodynamic equilibrium, the temperature which represents the averaged kinetic energy is demonstrated to have the proper property which is invariant under the Lorentz boost, using the conceptions of the relativistic quantum field theory and statistical physics. The thermodynamic interaction is described by the coupling of partic

C. Zhong, X. Z. Cai, W. Q. Shen, H. Y. Zhang

The Boltzmann-Uehling-Uhlenbeck (BUU) Model, which includes the Fermi motion, the mean field, individual nucleon-nucleon (N-N) interactions and the Pauli blocking effect etc., is used to calculate the total reaction cross section $σ_R$ induced by $α$-particles on different targets in the incident energy range from 17.4 to 48.1 MeV/u. The calculation result c

Y. B. Wei, X. Z. Cai, W. Q. Shen, Y. G. Ma

The isospin-dependent quantum molecular dynamics (IDQMD) model is used to study the total reaction cross section $σ_R$. The energy-dependent Pauli volumes of neutrons and protons have been discussed and introduced into the IDQMD calculation to replace the widely used energy-independent Pauli volumes. The modified IDQMD calculation can reproduce the experimen

Lorenzo Fortunato, Andrea Vitturi

An analytical solution of the collective Bohr equation with a Coulomb-like and a Kratzer-like $γ-$unstable potential in quadrupole deformation space is presented. Eigenvalues and eigenfunctions are given in closed form and transition rates are calculated for the two cases. The corresponding SO(2,1)$\times$SO(5) algebraic structure is discussed.

M. J. Ramsey-Musolf, J. Secrest

Studies in nuclear and atomic physics have played an important role in developing our understanding of the Standard Model of electroweak interactions. We review the basic ingredients of the Standard Model, and discuss some key nuclear and atomic physics experiments used in testing these ideas. We also summarize the conceptual issues of the Standard Model tha

P. Bydzovsky, F. Cusanno, S. Frullani, F. Garibaldi

Predictions of isobaric and Regge models are compared with the latest experimental data (Bonn,JLab) to select among the models those providing a satisfactory description of the data. Only the Saclay-Lyon and MAID models are in a reasonable agreement with both photo- and electro-production data ranging up to about 2.5 GeV.

Akira Ono, P. Danielewicz, W. A. Friedman, W. G. Lynch

Isoscaling is found to hold for fragment yields in the antisymmetrized molecular dynamics (AMD) simulations for collisions of calcium isotopes at 35 MeV/nucleon. This suggests the applicability of statistical considerations to the dynamical fragment emission. The observed linear relationship between the isoscaling parameters and the isospin asymmetry of frag

J. Arrington

Several experiments have extracted proton electromagnetic form factors from elastic cross section measurements using the Rosenbluth technique. Global analyses of these measurements indicate approximate scaling of the electric and magnetic form factors (mu_p*G_E/G_M = 1), in contrast to recent polarization transfer measurements from Jefferson Lab. We present

N. V. Antonov, Michal Hnatich, Juha Honkonen, Marian Jurcisin

The field-theoretic renormalization group (RG) and the operator product expansion are applied to the model of a divergence-free vector quantity, passively advected by the ``synthetic'' turbulent flow with a finite correlation time. The vector field is described by the stochastic advection-diffusion equation with the most general form of the inertial

Yoshio Uwano

In this paper, separability of the perturbed two-dimensional isotropic harmonic oscillators with homogeneous polynomial potentials is characterized from their Birkhoff-Gustavson (BG) normalization, one of the conventional methods for non-integrable Hamiltonian systems.

G. Gaeta, P. Morando

We provide a variational description of any Liouville (i.e. volume preserving) autonomous vector fields on a smooth manifold. This is obtained via a ``maximal degree'' variational principle; critical sections for this are integral manifolds for the Liouville vector field. We work in coordinates and provide explicit formulae.

P. J. Forrester, N. S. Witte

In this work we show that the $ N\times N $ Toeplitz determinants with the symbols $ z^μ\exp(-{1/2}\sqrt{t}(z+1/z)) $ and $ (1+z)^μ(1+1/z)^ν\exp(tz) $ -- known $τ$-functions for the \PIIIa and \PV systems -- are characterised by nonlinear recurrences for the reflection coefficients of the corresponding orthogonal polynomial system on the unit circle. It is s

Jianguo Cao, Mei-Chi Shaw, Lihe Wang

Let $Ω$ be a pseudoconvex domain with $C^2$-smooth boundary in $\mathbb CP^n$. We prove that the $\bar\partial-Neumann operator $N$ exists for $(p,q)$-forms on $Ω$. Furthermore, there exists a $t_0>0$ such that the operators $N$, $\bar\partial^*N$, $\bar\partial N$ and the Bergman projection are regular in the Sobolev space $W^t (\barΩ) $ for $t<t_0$. The bo

Vincent Colin, Emmanuel Giroux, Ko Honda

This is the less official, English version of the proof of the fact that every closed atoroidal 3-manifold carries finitely many isotopy classes of tight contact structures.

Stephen Doty

We obtain a presentation by generators and relations for generalized Schur algebras and their quantizations. This extends earlier results obtained in the type A case. The presentation is compatible with Lusztig&#39;s modified form of a quantized enveloping algebra. We show that generalized Schur algebras inherit a canonical basis from the modified form of th

G. Lusztig

We begin the study of character sheaves on a not necessarily connected reductive group, extending the known theory for connected groups.

Elie Feder

We begin with a review of the notion of a braid group. We then discuss some known solutions to decision problems in braid groups. We then move on to proving new results in braid group algorithmics. We offer a quick solution to the generalized word problem in braid groups, in the special case of cyclic subgroups. We illustrate this solution and its complexity

Toka Diagana

We prove that the algebraic sum of unbounded normal operators satisfies the square root problem of Kato under appropriate hypotheses. As application, we consider perturbed Schrodinger operators.

Marco Fontana, Pascual Jara, Eva Santos

We study the &#34;local&#34; behavior of several relevant properties concerning semistar operations, like finite type, stable, spectral, e.a.b. and a.b. We deal with the &#34;global&#34; problem of building a new semistar operation on a given integral domain, by &#34;gluing&#34; a given homogeneous family of semistar operations defined on a set of localizati

G. Molchan

An independent random cascade measure is specified by a random generator, a vector of dimension c with non-negative components. The dimension c is called the branching cascade parameter. It is shown under certain restrictions that, if this measure has two generators with a.s. positive components, and the ratio ln c_1/ln c_2 for their branching parameters is

M. Dutour

A Delaunay polytope $P$ is said to be {\em extreme} if the only (up to isometries) affine bijective transformations $f$ of $\R^n$, for which $f(P)$ is again a Delaunay polytope, are the homotheties. This notion was introduced in \cite{DGL92}; also some examples in dimension 1, 6, 7, 15, 16, 22, 23 were constructed and it was proved that in dimension less tha

Nguyen Anh Ky, Nguyen thi Hong Van

The quantum superalgebra $U_q[gl(2/1)]$ is given as both a Drinfel&#39;d--Jimbo deformation of $U[gl(2/1)]$ and a Hopf superalgebra. Finite--dimensional representations of this quantum superalgebra are constructed and investigated in a basis of its even subalgebra $U_q[gl(2)\oplus gl(1)]$. The present method for constructing representations of a quantum supe

Timothy Logvinenko

Let G be a finite subgroup of GL_n(C). A study is made of the ways in which resolutions of the quotient space C^n / G can parametrise G-constellations, that is, G-regular finite length sheaves. These generalise G-clusters, which are used in the McKay correspondence to construct resolutions of orbifold singularities. A complete classification theorem is achie

Athanasios Batakis

In this work we study the Hausdorff dimension of measures whose weight distribution satisfies a markov non-homogeneous property. We prove, in particular, that the Hausdorff dimensions of this kind of measures coincide with their lower Rényi dimensions (entropy). Moreover, we show that the Tricot dimensions (packing dimension) equal the upper Rényi dimensions

Luis Baez-Duarte

A quite fast proof of the functional equation of the Riemann zeta function. It is a modification of a proof usually overlooked in Titchmarsh&#39;s monograph.

Chang Heon Kim

Let $p$ be a prime for which the congruence group $Γ_0(p)^*$ is of genus zero, and $j_p^*$ be the corresponding Hauptmodul. Let $f$ be a nearly holomorphic modular form of weight 1/2 on $Γ_0(4p)$ which satisfies some congruence condition on its Fourier coefficients. We interpret $f$ as a vector valued modular form. Applying Borcherds lifting of vector valued

Morten Brun

We give, for every finite group G, a combinatorial description of the ring of G-Witt vectors on a polynomial algebra over the integers. Using this description we show that the functor, which takes a ring with trivial action of G to its ring of Witt vectors, coincides with the left adjoint of the algebraic functor from the category of G-Tambara functors to th

David Gamarnik

Our model is a generalized linear programming relaxation of a much studied random K-SAT problem. Specifically, a set of linear constraints C on K variables is fixed. From a pool of n variables, K variables are chosen uniformly at random and a constraint is chosen from C also uniformly at random. This procedure is repeated m times independently. We ask the fo

Henrique Boschi-Filho, Nelson R. F. Braga

Physical consistency of quantum fields in anti-de Sitter space time requires that the space must be compactified by the inclusion of a boundary where appropriate conditions are imposed. An interpretation for the presence of this boundary is found taking AdS as a limiting case of the space generated by a large number of coincident branes. The compactification

Victor O. Rivelles

We discuss the renormalization properties of noncommutative supersymmetric theories. We also discuss how the gauge field plays a role similar to gravity in noncommutative theories.

O. Ragnisco, R. Sasaki

The relationship (resemblance and/or contrast) between quantum and classical integrability in Ruijsenaars-Schneider systems, which are one parameter deformation of Calogero-Moser systems, is addressed. Many remarkable properties of classical Calogero and Sutherland systems (based on any root system) at equilibrium are reported in a previous paper (Corrigan-S

Tanwi Ghosh

Using a boundary prescription motivated by the Ads-Cft conjecture, I study the thermodynamical properties of the class of Kerr-Bolt-Ads spacetime.The stability conditions and the complete phase diagrams are investigated.

Graham D. Kribs

Little Higgs theories are a fascinating new idea to solve the little hierarchy problem by stabilizing the Higgs mass against one-loop quadratically divergent radiative corrections. In this talk I give a brief overview of the idea, focusing mainly on the littlest Higgs model, and present a sampling of the electroweak precision constraints.

J. Bernabeu, Sergio Palomares-Ruiz, S. T. Petcov

We derive predictions for the Nadir angle (theta(n)) dependence of the ratio N(mu)/N(e) of the rates of the mu-like and e-like multi-GeV events measured in water-Cerenkov detectors in the case of 3-neutrino oscillations of the atmospheric nu(e) (antinu(e)) and nu(mu) (antinu(mu)), driven by one neutrino mass squared difference, |Delta m2(31)| ~ (2.5 - 3.0) x

Felipe J. Llanes-Estrada, Antonio Dobado

We briefly report a calculation of the viscosity of a pion gas at finite temperature and chemical potential using three different models for the pion-pion interaction. The results for the Inverse Amplitude Method interpolation yield a viscosity of order (m_pi^3) up to temperatures of order m_pi. The calculation is performed within the kinetic theory of gases

A. Guffanti

We study the azimuthal correlation of hadron pairs produced in hadron-hadron collisions in the framework of perturbative QCD. We concentrate our attention on the `almost back-to-back&#39; region where resummation of large logarithms due to soft and/or collinear radiation are shown to play an important role. Our aim is to perform perturbative resummation at s

Veronique Van Elewyck

In the framework of Randall-Sundrum model, we discuss the evolution of microscopic black holes created by cosmic particles hitting a neutron or a strange star. We set up the general equations of evolution for the black hole mass and momentum in a dense medium, and discuss the possibility of collapse due to the black hole&#39;s growth inside the star.

Masayuki Uehara

We examine effects of final state interactions (FSI) in kaon decays using a new scheme without the Omnes function, and show that while Delta I=1/2 rule is impossible to be explained in terms of FSI alone, $ε&#39;/ε\sim 16.5\times 10^{-4}$ is obtained through FSI, if the calculation is concerned only with the CP-violating parts. The pi-pi contribution to the

Reinhard Stock

Relativistic nucleus-nucleus collisions create a &#34;fireball&#34; of strongly interacting matter at high energy density. At very high energy this is suggested to be partonic matter, but at lower energy it should consist of yet unknown hadronic, perhaps coherent degrees of freedom. The freeze-out of this high density state to a hadron gas can tell us about

K. Splittorff

Elitzur&#39;s theorem stating the impossibility of spontaneous breaking of local symmetries in a gauge theory is reexamined. The existing proofs of this theorem rely on gauge invariance as well as positivity of the weight in the Euclidean partition function. We examine the validity of Elitzur&#39;s theorem in gauge theories for which the Euclidean measure of

Gregory J. Sharp, Christopher D. Jones

Reconstruction of one run of CLEO III raw data can take up to 9 days to complete using a single processor. This is an administrative nightmare, and even minor failures result in reprocessing the entire run, which wastes time, money and CPU power. We leveraged the ability of the CLEO III software infrastructure to read and write multiple file formats to perfo

The OPAL collaboration

A search for stable and long-lived massive particles of electric charge |Q/e|=1 or fractional charges of 2/3, 4/3, and 5/3 is reported using data collected by the OPAL detector at LEP, at centre-of-mass energies from 130 to 209 GeV. These particles are assumed to be pair-produced in e+e- collisions and not to interact strongly. No evidence for the production

A. Murat Guler

The CHORUS experiment was designed to search for $ν_μ\to ν_τ$ oscillation by detecting the decay topology of the $τ$ in charged current (CC) $ν_τ$ events. The detector was exposed to the Wide Band Neutrino Beam of the CERN SPS during the years 1994-1997. About $10^{6} ν_μ$ CC events were collected in the nuclear emulsion target. Up to now, about 170,000 $ν_μ

Armin Böhrer

New results reported at the Moriond-QCD 2003 conference from the experiments ALEPH, DELPHI, L3, and OPAL on the structure of the photon as well as heavy quark production in gammagamma collisions are presented. The hadronic structure of the photon is studied in single-tagged events; the interaction of two virtual photons is investigated in double-tagged event

M. Castagnino, O. Lombardi

In this paper we adopt a global and non-entropic approach to the problem of the arrow of time, according to which the arrow of time is an intrinsic geometrical property of spacetime. Our main aim is to show the double role played by the energy-momentum tensor in the context of our approach. On the one hand, the energy-momentum tensor is the intermediate step

Robert Brout

To confront the transplanckian problem encountered in the backward extrapolation of the cosmological expansion of the momenta of the modes of quantum field theory, it is proposed that there is a reservoir, depository of transplanckian degrees of freedom. These are solicited by the cisplanckian modes so as to keep their density fixed and the total energy dens

G. Lawes, A. P. Ramirez, C. M. Varma, M. A. Subramanian

We report on the effects of spin fluctuations, magnetic ordering, and external magnetic field on the dielectric constant of the ferromagnet SeCuO3, and the antiferromagnet TeCuO3. A model based on the coupling between uniform polarization and the q-dependent spin-spin correlation function is presented to explain the different behaviors for these isostructura

Sven P. Rudin, M. D. Jones, R. C. Albers

We have used a tight-binding model that is fit to first-principles electronic-structure calculations for titanium to calculate quasi-harmonic phonons and the Gibbs free energy of the hexagonal close-packed (hcp) and omega crystal structures. We show that the true zero-temperature ground-state is the omega structure, although this has never been observed expe

A. A. Zherebtsov, Yu. A. Kuperin

In this paper we apply the Self-Organized Map (SOM) method for clustering the DJIA and NASDAQ100 portfolios for determination of non-linear correlations between stocks. We represent the application of this method as alternative to ultrametric spaces method. We have found, that SOM method is more relevant and perspective for clustering ill-structured large da

S. M. Nakhmanson, A. Calzolari, V. Meunier, J. Bernholc

Ab initio calculations of the spontaneous polarization and piezoelectric properties of boron nitride nanotubes show that they are excellent piezoelectric systems with response values larger than those of piezoelectric polymers. The intrinsic chiral symmetry of the nanotubes induces an exact cancellation of the total spontaneous polarization in ideal, isolate

T. Jarlborg

The T-dependence of magnetic moments in SrB_6 is studied through spin-polarized band calculations for a supercell of Sr_{27}B_{156} containing a B_6 vacancy. The magnetic moment decays rather quickly with T despite the fact that only electronic Fermi-Dirac effects are included. This result and the T-dependence of moments near a La impurity can hardly explain

Pascal Simon, Ian Affleck

We study how finite size effects may appear when a quantum dot in the Kondo Coulomb blockade regime is embedded into a mesoscopic device with finite wires. These finite size effects appear when the size of the mesoscopic device containing the quantum dot is of the order of the size of Kondo cloud and affect all thermodynamic and transport properties of the K

N. Andrenacci, P. Pieri, G. C. Strinati

We consider the current correlation function for a three-dimensional system of fermions embedded in a homogeneous background and mutually interacting via an attractive short-range potential, below the (superconducting) critical temperature. Diagrammatic contributions in the broken-symmetry phase are identified, that yield for the (wave-vector and frequency d

G. De Marzi, H. J. Trodahl, J. Bok, A. Cantarero

We report on the first Raman data of Cu substituted La(1-y)Sr(y)Mn(1-x)Cu(x)O3 (0 < x < 0.10 and 0.17 < y < 0.3, accordingly in order to have the same Mn(4+)/[Mn(4+)+Mn(3+)] ratio), collected in the frequency range 100-900 cm-1 and at room temperature, with parallel and crossed polarizations of the incident and scattered light. Spectra were fitted with a Dru

R. Winkler

Inversion asymmetry induced spin splitting of the electron states in quasi two-dimensional (2D) systems can be attributed to an effective magnetic field B which varies in magnitude and orientation as a function of the in-plane wave vector k||. Using a realistic 8x8 Kane model that fully takes into account spin splitting because of both bulk inversion asymmet

Wei-Xue Li, Catherine Stampfl, Matthias Scheffler

To help understand the high activity of silver as an oxidation catalyst, e.g., for the oxidation of ethylene to epoxide and the dehydrogenation of methanol to formaldehyde, the interaction and stability of oxygen species at the Ag(111) surface has been studied for a wide range of coverages. Through calculation of the free energy, as obtained from density-fun

Janine Splettstoesser, Michele Governale, Ulrich Zuelicke

The presence of spin-orbit coupling affects the spontaneously flowing persistent currents in mesoscopic conducting rings. Here we analyze their dependence on magnetic flux with emphasis on identifying possibilities to prove the presence and extract the strength of Rashba spin splitting in low-dimensional systems. Effects of disorder and mixing between quasi-

Weizhu Bao

We study numerically the time-independent vector Gross-Pitaevskii equations (VGPEs) for ground states and time-dependent VGPEs with (or without) an external driven field for dynamics describing a multi-component Bose-Einstein condensate (BEC) at zero or very low temperature. In preparation for the numerics, we scale the 3d VGPEs, approximately reduce it to l

Fabien Picaud, Alexander Smogunov, Andrea Dal Corso, Erio Tosatti

The complex band structure of an isolated polyethylene chain is calculated within Density Functional Theory (DFT). A plane wave basis and ultrasoft pseudopotentials are used. The results are compared with those obtained via a local basis set. We obtain a gap between the highest occupied molecular orbilar (HOMO) and the antibonding unoccupied molecular orbita

Rina Kanamoto, Hiroki Saito, Masahito Ueda

We investigate rotational properties of a system of bosons with attractive interactions confined in a one-dimensional torus. Two kinds of ground states, uniform-density and bright-soliton states, are obtained analytically as functions of the strength of interaction and of the rotational frequency of the torus. The quantization of circulation appears in the u

Stefan Grosskinsky, Herbert Spohn

We study general zero range processes with different types of particles on a d-dimensional lattice with periodic boundary conditions. A necessary and sufficient condition on the jump rates for the existence of stationary product measures is established. For translation invariant jump rates we prove the hydrodynamic limit on the Euler scale using Yau&#39;s re

J. H. Durrell, M. J. Hogg, F. Kahlmann, Z. H. Barber

Transport critical current measurements have been performed on 5 degree [001]-tilt thin film YBa2Cu3O7-delta single grain boundaries with magnetic field rotated in the plane of the film, phi. The variation of the critical current has been determined as a function of the angle between the magnetic field and the grain boundary plane. In applied fields above 1

A. K. Aringazin, M. I. Mazhitov

We describe a formal procedure to obtain and specify the general form of a marginal distribution for the Lagrangian acceleration of fluid particle in developed turbulent flow using Langevin type equation and the assumption that velocity fluctuation $u$ follows a normal distribution with zero mean, in accord to the Heisenberg-Yaglom picture. For a particular

Kenji Kamide, Takashi Kimura, Munihiro Nishida, Susumu Kurihara

We discuss phase diagrams obtained by calculating temperature dependent correlation functions for superconductivity and density waves for a single (5,0) carbon nanotube (CN). We use one-loop renormalization group method within logarithmic accuracy. In this system we must specify scattering channels in terms of momentum along the circumferential direction as

C. J. Odman

The recent WMAP data represents a milestone in cosmology and helps constrain cosmological parameters with unprecedented accuracy. In this work we combine the WMAP data with previous CMB anisotropy measurements at smaller angular scales to characterize the shape of the CMB anisotropy power spectrum. We carry out a phenomenological analysis of the data. By all

A. Sozzetti, S. Casertano, R. A. Brown, M. G. Lattanzi

(Abridged) The probability of detecting additional companions is essentially unchanged with respect to the single-planet configurations, but after fitting and subtraction of orbits with astrometric signal-to-noise ratio $α/σ_d\to 1$ the false detection rates can be enhanced by up to a factor 2; the periodogram approach results in robust multiple-planet detec

Pasquale Blasi, Stefano Gabici

The nonthermal radiation observed from a handfull of clusters of Galaxies is the proof that particle acceleration occurs in the intracluster medium. It is often believed that shock surfaces associated with either mergers of clusters of galaxies, or with the cosmological inflow of matter onto clusters during structure formation may be the sites for accelerati

Y. Ascasibar

Clusters of galaxies are studied from a theoretical point of view, comparing with observational results whenever possible. The problem is approached both analytically as well as by means of high-resoultion numerical simulations. The dark matter halo, the hot intracluster gas, and the stellar component are investigated separately. Numerical clusters are consi

C. Raeth, P. Schuecker

The identification of non-Gaussian signatures in cosmic microwave background (CMB) temperature maps is one of the main cosmological challenges today. We propose and investigate altenative methods to analyse CMB maps. Using the technique of constrained randomisation we construct surrogate maps which mimic both the power spectrum and the amplitude distribution

David L. Block, Ivanio Puerari, Marianne Takamiya, Robert G. Abraham

Quantitative morphological dust-penetrated templates for galaxies in our Local Universe may also serve as excellent templates for galaxies at high-z, because of partial/total decouplings expected between gaseous and stellar disks. NGC 922 is an optical irregular, which bears a striking resemblance to objects such as HDF2-86 (z=0.749) in the HDF north (Block

U. C. Joshi, K. S. Baliyan, S. Ganesh

Linear polarization observations were carried out on comet C/2000 WM1 with the 1.2m telescope at Mt. Abu Observatory during November 2001 and March 2002. The observations in November were at low phase angle ($<~22\degr$) when the polarization is negative and where the data for most of the comets are rather meager. The observations during March were made when

M. Einasto, J. Jaaniste, J. Einasto, P. Heinämäki

We study the spatial distribution of loose groups from the Las Campanas Redshift Survey, comparing it with the supercluster-void network delineated by rich clusters of galaxies. We use density fields and the friends-of-friends algorithm to identify the members of superclusters of Abell clusters among the Las Campanas loose groups. We find that systems of loo

Th. Boller, Y. Tanaka, A. Fabian, W. N. Brandt

We report on the first XMM-Newton observation of the highly X-ray variable, radio-quiet, Narrow-Line Seyfert 1 galaxy IRAS 13224-3809 obtained during the guaranteed time programme with a 64 ks exposure. The most remarkable spectral feature is a sharp drop, by a factor ~5, in the spectrum at 8 keV. This is a similar, but stronger, feature to that which we fou

M. Girardi, E. Rigoni, F. Mardirossian, M. Mezzetti

We study morphology and luminosity segregation of galaxies in loose groups. We analyze the two catalogs of groups which have been identified in the Nearby Optical Galaxy (NOG) sample, by means of hierarchical and percolation ``friends-of-friends&#39;&#39; methods (HG and PG catalogs, respectively). In the first part of our analysis we consider 387 and 436 gr

S. P. Ellingsen, D. M. Cragg, V. Minier, E. Muller

We have used the Australia Telescope National Facility Mopra 22m millimetre telescope to search for emission from the 85.5-GHz and 86.6-GHz transitions of methanol. The search was targeted towards 22 star formation regions which exhibit maser emission in the 107.0-GHz methanol transition, as well as in the 6.6-GHz transition characteristic of class II methan

Simon Johnston, Roger W. Romani

We report the discovery of the first giant pulses from an extragalactic radio pulsar. Observations of PSR B0540-69 in the Large Magellanic Cloud made with the Parkes radio telescope at 1.38 GHz show single pulses with energy more than 5000 times that of the average pulse energy. This is only the second young pulsar, after the Crab, to show giant pulse emissi

Yuri V. Lvov, Sergey Nazarenko

We study the k-space fluctuations of the waveaction about its mean spectrum in the turbulence of dispersive waves. We use a minimal model based on the Random Phase Approximation (RPA) and derive evolution equations for the arbitrary-order one-point moments of the wave intensity in the wavenumber space. The first equation in this series is the familiar Kineti

Michael Gronau

We comment on a recent suggestion for measuring $γ$ in $B^0(t)\to K_Sπ^+π^-$. A difficulty is pointed out in relating electroweak penguin and tree amplitudes in $B^+\to K^0π^+π^0$, which is crucial for an implementation of this method. We clarify the necessary condition for such a relation.

L. Tewordt, D. Fay

We solve the coupled gap equations for the $σ$- and $π$-bands of MgB$_2$ in the vortex state and calculate the resulting field dependencies of the specific heat coefficient $γ$ and the thermal conductivity $κ$. The crucial parameters of the theory are the interband pairing interaction $λ_{πσ}$ and the ratio $s=ξ_σ/ξ_π$ of the coherence lengths. For reasonabl

Laszlo Zalanyi, Gabor Csardi, Tamas Kiss, Mate Lengyel

In this study we introduce and analyze the statistical structural properties of a model of growing networks which may be relevant to social networks. At each step a new node is added which selects &#39;k&#39; possible partners from the existing network and joins them with probability delta by undirected edges. The &#39;activity&#39; of the node ends here; it

Igor F. Herbut, Babak H. Seradjeh

We argue that the compact three dimensional electrodynamics with massless fermions is always confining, in spite of the bare interaction between the magnetic monopoles being rendered logarithmic by fermions. The effect is caused by screening by other dipoles, which transforms the logarithmic back into the Coulomb interaction at large distances. Possible impl

R. Rapp, L. Grandchamp

Recent developments in the theoretical evaluation of charmonium production in ultrarelativistic heavy-ion collisions (URHIC&#39;s) are discussed. In particular, the consequences of equilibrium properties of open and hidden charm states -- accessible, {\it e.g.}, in QCD lattice gauge calculations -- are assessed. These include abundances as well as formation

G. Guralnik, A. Iorio, R. Jackiw, S. -Y. Pi

When the gravitational Chern-Simons term is reduced from 3 to 2 dimensions, the lower dimensional theory supports a symmetry breaking solution and an associated kink. Kinks in general relativity bear a close relation to flat space kinks, governed by identical potentials.

Iosif Bena, Joseph Polchinski, Radu Roiban

Attempts to solve Yang-Mills theory must eventually face the problem of analyzing the theory at intermediate values of the coupling constant. In this regime neither perturbation theory nor the gravity dual are adequate, and one must consider the full string theory in the appropriate background. We suggest that in some nontrivial cases the world sheet theory

Paul Sorensen

The elliptic flow parameter ($v_2$) for $K_S^0$ and $Λ+\barΛ$ has been measured at mid-rapidity in Au + Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV by the STAR collaboration. The $v_2$ values for both $K_S^{0}$ and $Λ+\barΛ$ saturate at moderate $p_T$, deviating from the hydrodynamic behavior observed in the lower $p_T$ region. The saturated $v_2$ values and

A. Kvinikhidze, B. Blankleider

It is shown that light front thermal field theory is equivalent to conventional thermal field theory. The proof is based on the use of spectral representations, and applies to all Lagrangians for which such equivalence has been proven at zero temperature. It is also pointed out that conventional spectral functions can be used to express light-front finite te

M. Veselsky, G. A. Souliotis, S. J. Yennello

The isoscaling is investigated using the fragment yield data from fully reconstructed quasi-projectiles observed in peripheral collisions of 28Si with 124,112Sn at projectile energies 30 and 50 MeV/nucleon. The excitation energy dependence of the isoscaling parameter beta_prime is observed which is independent of beam energy. For a given quasi-projectile pro

Danny Birmingham, Steven Carlip, Yujun Chen

We explore the relationship between classical quasinormal mode frequencies and black hole quantum mechanics in 2+1 dimensions. Following a suggestion of Hod, we identify the real part of the quasinormal frequencies with the fundamental quanta of black hole mass and angular momentum. We find that this identification leads to the correct quantum behavior of th

A. Bill, H. Morawitz, V. Z. Kresin

A distinctive feature of layered conductors is the presence of low-energy electronic collective modes of the conduction electrons. This affects the dynamic screening properties of the Coulomb interaction in a layered material. We study the consequences of the existence of these collective modes for superconductivity. General equations for the superconducting

P. -Y. Longaretti

A new criterion for pressure-driven interchange instabilities in cylindrical geometry is derived, based on an alternate use of the Energy Principle. This criterion is inequivalent to Suydam&#39;s criterion and does not contain the magnetic shear. In fact, it is shown that Suydam&#39;s criterion relates to the instability of the slow magnetosonic branch, whil

S. Yu. Sazonov, J. P. Ostriker, R. A. Sunyaev

Using information on the cosmic X-ray background and the cumulative light of active galactic nuclei at infrared wavelengths, the estimated local mass density of galactic massive black holes (MBHs) and published AGN composite spectra in the optical, UV and X-ray, we compute the characteristic angular-integrated, broad-band spectral energy distribution of the

J. Scharwaechter, A. Eckart, S. Pfalzner, J. Moultaka

The paper presents an analysis of the nearby QSO host I Zw 1 based on new J-band imaging data, obtained with ISAAC at the Very Large Telescope (VLT) of the European Southern Observatory (ESO). As one of the best-studied QSOs with exceptional properties lying between those of QSOs, narrow-line Seyfert 1s, and ultraluminous infrared galaxies, I Zw 1 is a prime

D. V. Fil, S. I. Shevchenko

An effect of nondissipative drag of a superfluid flow in a system of two Bose gases confined in two parallel quasi two-dimensional traps is studied. Using an approach based on introduction of density and phase operators we compute the drag current at zero and finite temperatures for arbitrary ratio of densities of the particles in the adjacent layers. We dem