January 2003 arXiv papers — page 28

Xiao-Yin Pan, Viraht Sahni

In this paper we construct such a set of `degenerate' Hamiltonians $\hat{H}$, which differ by an `intrinsic' constant but represent different physical systems yet possess the same ground state density. . Thus, although the proof of Hohenberg-Kohn (HK) theorem is independent of whether the constant $C$ is additive or intrinsic, its applicability is re

T. J. Galama, D. Reichart, T. M. Brown, R. A. Kimble

We report on Hubble Space Telescope WFPC2 optical and STIS near ultraviolet MAMA observations, and ground-based optical observations of GRB010222, spanning 15 hrs to 71 days. The observations are well-described by a relativistic blast-wave model with a hard electron-energy distribution, p = 1.57, and a jet transition at t_j=0.93 days. These values are slight

James S. Ulvestad

The advent of the Very Long Baseline Array and its phase-referencing capability have enabled milliarcsecond-scale imaging of radio sources at sub-millijansky sensitivity, opening the door to high-resolution imaging of Seyfert galaxies. Over the last few years, this has led to a number of interesting new results that shed light on the characteristics of the i

S. Pustilnik, A. Zasov, A. Kniazev, A. Pramskij

In continuation of the program formulated in Paper I we present results of long-slit spectroscopy with the Russian 6m telescope of five more objects from the Vorontsov-Velyaminov Atlas and Catalogue of Interacting galaxies. These are the galaxies for which the interaction is not evident, although all of them are classified as multiple systems (usually as ``n

Y. M. Cho

We review the quantum instability of the Savvidy-Nielsen-Olesen (SNO) vacuum of the one-loop effective action of SU(2) QCD, and point out a critical defect in the calculation of the functional determinant of the gluon loop in the SNO effective action. We prove that the gauge invariance, in particular the color reflection invariance, exclude the unstable tach

Christopher M. Hirata, Uros Seljak

We investigate biases induced by the conversion between the observed image shape to shear distortion in current weak lensing analysis methods. Such overall calibration biases cannot be detected by the standard tests such as E/B decomposition or calibration with stars. We find that the non-Gaussianity of point spread function has a significant effect and can

Alexander Barabanschikov

We consider a $σ$-model formulation of open string theory in the presence of D-branes. We perform two-loop computations and discuss gravitational corrections to Born-Infeld action when branes are non-trivially embedded in a curved ambient space. In particular for the case of a stack of $N$ coincident D-branes we analyze couplings of the form $R_{ijkl}[Φ^i,Φ^

Changhyun Ahn

By performing the matrix integral over the tree level superpotential of N=1 supersymmetric SO(N)/Sp(N) gauge theories obtained from N=2 SQCD by adding the mass term for the adjoint scalar field, the exact effective superpotential in terms of meson field contains the nonperturbative ADS superpotential as well as the classical tree level superpotential. By com

Gamal G. L. Nashed

The singularity of the black hole solutions obtained before in Møller's theory are studied. It is found that although the two solutions reproduce the same associated metric the asymptotic behavior of the scalars of torsion tensor and basic vector are quite different. The stability of the associated metric of those solutions which is spherically symmetric

Cigdem Issever

We present the status of the forward-backward charge asymmetry measurement for W boson production using early Run 2 data collected with the Collider Detector at Fermilab (CDF). Tracking for forward electrons is a critical component of this measurement, and we describe a new technique which combines the position and energy measurements from the calorimeter wi

David Aldous, Allon G. Percus

We consider combinatorial optimization problems defined over random ensembles, and study how solution cost increases when the optimal solution undergoes a small perturbation delta. For the minimum spanning tree, the increase in cost scales as delta^2; for the mean-field and Euclidean minimum matching and traveling salesman problems in dimension d>=2, the inc

Y. Muraoka, Z. Hiroi

This paper has been withdrawn by the author(s), due a crucial error in the data.

Habibollah Razmi

For a special stochastic realistic model in certain spin-correlation experiments and without imposing the locality condition, an inequality is found. Then, it is shown that quantum theory is able (is possible) to violate this inequality. This shows that, irrelevance of the locality condition, the quantum entanglement of the spin singlet-state is the reason f

L. Jakobczyk

It is shown that the dissipation due to spontaneous emission can entangle two closely separated two-level atoms.

A. V. Afanasjev, T. L. Khoo, S. Frauendorf, G. A. Lalazissis

The cranked relativistic Hartree+Bogoliubov theory has been applied for a systematic study of the nuclei around 254No, the heaviest nuclei for which detailed spectroscopic data are available. The deformation, rotational response, pairing correlations, quasi-particle and other properties of these nuclei have been studied with different relativistic mean field

A. V. Afanasjev, T. L. Khoo, S. Frauendorf, G. A. Lalazissis

The cranked relativistic Hartree+Bogoliubov theory has been applied for a systematic study of the nuclei around 254No, the heaviest elements for which detailed spectroscopic data are available. The deformation, rotational response, pairing correlations, quasi-particle and other properties of these nuclei have been studied with different parametrizations for

M. A. Jafarizadeh, S. Behnia

Hierarchy of one and many-parameter families of random trigonometric chaotic maps and one-parameter random elliptic chaotic maps of $\bf{cn}$ type with an invariant measure have been introduced. Using the invariant measure (Sinai-Ruelle-Bowen measure), the Kolmogrov-Sinai entropy of the random chaotic maps have been calculated analytically, where the numeric

P. R. Crompton

A discussion of the overlap problem of reweighting approaches to evaluating critical phenomenon in fermionic systems is motivated by highlighting the divergence of the joint probability density function of a general ratio. By identifying the bounds for which this integral can be expressed in closed form, we establish criteria for accurately mapping the joint

O. V. Patsahan

Recently we proposed a microscopic approach to the description of the phase behaviour and critical phenomena in binary fluid mixtures. It was based on the method of collective variables (CV) with a reference system. The approach allowed us to obtain the functional of the Ginzburg-Landau-Wilson (GLW) Hamiltonian expressed in terms of the CV (fluctuating densi

F. Tabatabaee, A. Aghamohammadi

A two species reaction-diffusion model, in which particles diffuse on a one-dimensional lattice and annihilate when meeting each other, has been investigated. Mean field equations for general choice of reaction rates have been solved exactly. Cluster mean field approximation of the model is also studied. It is shown that, the general form of large time behav

G. G. Sergeeva, V. L. Vakula

Dynamical Dimension Reduction in Underdoped High Temperature Superconductors G.G.Sergeeva (National Science Center "Kharkov Institute of Physics and Technology",Ukraine), V.L.Vakula (B.Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine) Abstract For underdoped cuprate HTSC we discuss the suppos

Y. Tanaka, K. Kuroki, Y. Tanuma, S. Kashiwaya

The effect of the Doppler shift is studied in a model for the $α$-$β$ bands of Sr$_2$RuO$_4$ consisting of two hybridized 1D bands. Assuming a superconducting gap with nodes in the diagonal directions, we examine the oscillation of the surface density of states and the thermal conductivity under a rotating magnetic field. Upon varying the strength of the hyb

Rajan M. Lukose, Lada A. Adamic

We study the growth of random networks under a constraint that the diameter, defined as the average shortest path length between all nodes, remains approximately constant. We show that if the graph maintains the form of its degree distribution then that distribution must be approximately scale-free with an exponent between 2 and 3. The diameter constraint ca

A. K. Aringazin, M. I. Mazhitov

We propose a simple phenomenological modification, a Gaussian screening, of the probability distribution function which was obtained by Beck to explain experimentally measured distribution from fully developed fluid turbulence, within the framework of nonextensive statistical mechanics. The modified distribution provides a good fit to new experimental result

I. E. Mazets

We demonstrate a possibility to create a new state of ultracold atoms which we call a Bose-Einstein-Young condensate. Atoms are supposed to be in different hyperfine state of the same isotope. The wave function of such a state, although totally symmetric with respect to simultaneous permutation of co-ordinates and spins of any pair of atoms, has more complic

D. J. Macomb, D. W. Fox, R. C. Lamb, T. A. Prince

The Small Magellanic Cloud is increasingly an invaluable laboratory for studying accreting and isolated X-ray pulsars. We add to the class of compact SMC objects by reporting the discovery of three new long period X-ray pulsars detected with the {\it Chandra X-ray Observatory}. The pulsars, with periods of 152, 304 and 565 seconds, all show hard X-ray spectr

Jian Feng Ji, Shuang Nan Zhang, Jin Lu Qu, Ti Pei Li

We present results from the analysis of X-ray power density spectra and coherence when GRS 1915+105 is in soft states. We use three data sets that belong to $μ$, $ϕ$ and $δ$ classes in Belloni et al (2000). We find that the power density spectra appear to be complex, with several features between 0.01 and 10 Hz. The coherence deviates from unity above a char

M. Konacki, G. Torres, S. Jha, D. Sasselov

We have measured radial velocities of a star, OGLE-TR-56, which shows a 1.2-day transit-like light curve found photometrically by Udalski et al.(2002ab). Here we show that the velocity changes we detect are probably induced by an object of 0.9 Jupiter masses - a very close-in gas-giant planet only 0.023 AU from its star, with a planetary radius of 1.3 Jupite

Z. Nussinov, M. F. Crommie, A. V. Balatsky

We show how the noise in a spin polarized STM tunneling current gives valuable spectroscopic information on the temporal susceptibility of a single magnetic atom residing on a non-magnetic surface.

V. Protopopescu, C. D'Helon, J. Barhen

A constant-time solution of the continuous Global Optimization Problem (GOP) is obtained by using an ensemble algorithm. We show that under certain assumptions, the solution can be guaranteed by mapping the GOP onto a discrete unsorted search problem, whereupon Bruschweiler's ensemble search algorithm is applied. For adequate sensitivities of the measure

Gia-Wei Chern, Chi-Kuang Sun, Yue-Kai Huang, Kung-Hsuan Lin

We review some experimental and theoretical aspects of coherent acoustic phonon generation in piezoelectric semiconductor multiple quantum wells. In order to model more advanced and complicated nano-acoustic devices, a macroscopic continuum theory for the generation and propagation of coherent acoustic phonons in piezoelectric semiconductor heterostructures

C. D'Helon, V. Protopopescu, R. Perez

We present an open-loop (bang-bang) scheme which drives an open two-level quantum system to any target state, while maintaining quantum coherence throughout the process. The control is illustrated by a realistic simulation for both adiabatic and thermal decoherence. In the thermal decoherence regime, the control achieved by the proposed scheme is qualitative

Benjamin Gold, Andreas Albrecht

The increasing precision of cosmological datasets is opening up new opportunities to test predictions from cosmic inflation. Here we study the impact of high precision constraints on the primordial power spectrum and show how a new generation of observations can provide impressive new tests of the slow-roll inflation paradigm, as well as produce significant

Ilia Gogoladze, Yukihiro Mimura, S. Nandi

We construct a supersymmetric left-right model in four dimension with gauge-Higgs unification starting from a SU(3)_c x SU(4)_w x U(1)_{B-L} gauge symmetry in five dimension. The model has several interesting features, such as, the CKM mixings in the quark sector are naturally small while for the neutrino sector it is not, light neutrino masses can be genera

I. A. Sergienko, S. H. Curnoe

It is shown that both structural phase transitions in Cd2Re2O7, which occur at T_{s1}=200 K and T_{s2}=120 K, are due to an instability of the Re tetrahedral network with respect to the same doubly degenerate long-wavelength phonon mode. The primary structural order parameter transforms according to the irreducible representation E_u of the point group O_h.

E. Tutuc, S. Melinte, E. P. De Poortere, M. Shayegan

We report measurements and calculations of the spin-polarization, induced by a parallel magnetic field, of interacting, dilute, two-dimensional electron systems confined to GaAs/AlGaAs heterostructures. The results reveal the crucial role the non-zero electron layer thickness plays: it causes a deformation of the energy surface in the presence of a parallel

Peter F. Kolb, Madappa Prakash

Invariant mass distributions of the hadronic decay products from resonances formed in relativistic heavy ion collision (RHIC) experiments are investigated with a view to disentangle the effects of thermal motion and the phase space of decay products from those of intrinsic changes in the structure of resonances at the freeze-out conditions. Analytic results

M. Avdeev, J. D. Jorgensen, R. A. Ribeiro, S. L. Bud'ko

Neutron powder diffraction has been used to characterize a sample of C-substituted MgB2 synthesized from Mg and B4C (with isotopically enriched 11B). The sample is multiphase, with the major phase [73.4(1) wt.%] being Mg(B1-xCx)2 with x=0.10(2). Minor phases include MgB2C2, Mg, and MgO. The major Mg(B1-xCx)2 phase displays diffraction peak widths as sharp as

L. Ya. Glozman

Chiral symmetry restoration in high-lying hadron spectra implies that hadrons which belong to different irreducible representations of the parity-chiral group cannot mix. This explains why the $f_0(2102 \pm 13)$, which was suggested to be a glueball, and hence must belong to the scalar (0,0) representation of the chiral group, cannot mix with the neighbourin

M. Laine

The dimensionally reduced action is believed to provide for a theoretically consistent and numerically precise effective description of the thermodynamics of the quark-gluon plasma, once the temperature is above a few hundred MeV. Although dramatically simpler than the original QCD it is, however, still a strongly interacting, confining theory. In this talk

R. R. Metsaev

The superfield light cone gauge formulation of $\mathcal{N} =4$ SYM in plane wave background is developed. We find a realization of superconformal symmetries in terms of a light cone superfield. An oscillator realization of superconformal symmetries is also obtained.

Da-Ming Chen

Lensing probabilities of quasars with image separations greater than Δθand flux density ratios less than q_{\mathrm{r}} are calculated by foreground dark matter halos in a flat, cosmological constant dominated (\LambdaCDM) universe . The mass density of the lenses is taken to be the Navarro-Frenk-White (NFW) profile on all mass scales, plus a central point m

Jesper Levinsen

In the framework of chiral perturbation theory we demonstrate the equivalence of the supersymmetric and the replica methods in the symmetry breaking classes of Dyson indices β=1 and β=4. Schwinger-Dyson equations are used to derive a universal differential equation for the finite volume partition function in sectors of fixed topological charge, ν. All depend

A. Panaitescu, P. Kumar

We investigate analytically the effect of an anisotropic distribution of the kinetic energy within a relativistic fireball on the decay of the afterglow emission, focusing on axially symmetric fireballs with a uniform core and a power-law decrease with angle outside the core. The afterglow fall-off steepens after the core becomes fully visible. For observer

Yu. Dabaghian, R. Blümel

Based on earlier work on regular quantum graphs we show that a large class of scaling quantum graphs with arbitrary topology are explicitly analytically solvable. This is surprising since quantum graphs are excellent models of quantum chaos and quantum chaotic systems are not usually explicitly analytically solvable.

Paolo Padoan, Raul Jimenez, Aake Nordlund, Stanislav Boldyrev

Supersonic turbulent flows of magnetized gas are believed to play an important role in the dynamics of star-forming clouds in galaxies. Understanding statistical properties of such flows is crucial for developing a theory of star formation. In this letter we propose a unified approach for obtaining the velocity scaling in compressible and super--Alfvénic tur

W. Detmold

In a scalar $ϕ^2χ$ model, we exactly solve the vertex and $ϕ$ propagator Dyson-Schwinger equations under the assumption of a spatially constant (Munczek-Nemirovsky) propagator for the $χ$ field. Various truncation schemes are also considered.

Takemi Okamoto, Wayne Hu

Gravitational lensing of the microwave background by the intervening dark matter mainly arises from large-angle fluctuations in the projected gravitational potential and hence offers a unique opportunity to study the physics of the dark sector at large scales. Studies with surveys that cover greater than a percent of the sky will require techniques that inco

S. Sivasubramanian, Y. N. Srivastava, G. Vitiello, A. Widom

The quantum statistical dynamics of a position coordinate x coupled to a reservoir requires theoretically two copies of the position coordinate within the reduced density matrix description. One coordinate moves forward in time while the other coordinate moves backward in time. It is shown that quantum dissipation induces, in the plane of the forward and bac

A. V. Yurov

Using Albert results we argue that we don't need new physics to understand Gödelization. Albert quantum automaton can "understand" both a formal system and a Gödel proposition which can't be obtained within this system. There are two significant conclusions. The first speaks "against Penrose" whereas the second speaks for him.

W. C. Haxton

These lectures, presented at the International School of Physics ``Enrico Fermi,'' deal with two major themes. The first is the remarkable story of the solar neutrino problem, which (along with the atmospheric neutrino anomaly) recently led to the discovery of massive neutrinos and neutrino oscillations, physics beyond the standard model. I will desc

R. Hernandez Heredero, A. Shabat, V. Sokolov

Using the symmetry approach, we find a class of integrable nonlinear PDEs with dispersion law $ω(k)=k^{\frac32}$. All these equations turn out to be linearizable by means of a differential parametrization.

Gerald Kaiser

Point sources in complex spacetime, which generate acoustic and electromagnetic pulsed-beam wavelets, are rigorously defined and computed with a view toward their realization.

Hongling Su, Mengzhao Qin

A universal symplectic structure for a Newtonian system including nonconservative cases can be constructed in the framework of Birkhoffian generalization of Hamiltonian mechanics. In this paper the symplectic geometry structure of Birkhoffian system is discussed, then the symplecticity of Birkhoffian phase flow is presented. Based on these properties we give

A. Gerasimov, S. Kharchev, D. Lebedev

In this paper we define a new class of the quantum integrable systems associated with the quantization of the cotangent bundle $T^*(GL(N))$ to the Lie algebra $\frak{gl}_N$. The construction is based on the Gelfand-Zetlin maximal commuting subalgebra in $U(\frak{gl}_N)$. We discuss the connection with the other known integrable systems based on $T^*GL(N)$. T

Raf Cluckers

A semialgebraic bijection from the field of p-adic numbers to itself minus one point is constructed. Semialgebraic p-adic sets are classified up to semialgebraic bijection. A cell decomposition theorem for restricted analytic p-adic maps is proven, in analogy with the cell decomposition theorem for polynomial maps by Denef. This cell decomposition is used to

N. Aizawa, R. Chakrabarti, J. Segar

A triangular quantum deformation of $ osp(2/1) $ from the classical $r$-matrix including an odd generator is presented with its full Hopf algebra structure. The deformation maps, twisting element and tensor operators are considered for the deformed $ osp(2/1)$. It is also shown that its subalgebra generated by the Borel subalgebra is self-dual.

Jan Kneissler

A new filtration of the spaces of tri-/univalent graphs B_m^u that occur in the theory of finite-type invariants of knots and 3-manifolds is introduced. Combining the results of the two preceding articles, the quotients of this filtration are modeled by spaces of graphs with two types of edges and four types of vertices, and an upper bound for dim B_m^u in t

Jan Kneissler

The graded algebra Lambda defined by Pierre Vogel is of general interest in the theory of finite-type invariants of knots and of 3-manifolds because it acts on the corresponding spaces of connected graphs subject to relations called IHX and AS. We examine a subalgebra Lambda_0 that is generated by certain elements called t and x_n with n >= 3. Two families o

Jan Kneissler

We examine spaces of connected tri-/univalent graphs subject to local relations which are motivated by the theory of Vassiliev invariants. It is shown that the behaviour of ladder-like subgraphs is strongly related to the parity of the number of rungs: there are similar relations for ladders of even and odd lengths, respectively. Moreover, we prove that - un

Andrew V. Batrac

A mathematical relation between elements of one- and multi-dimensional discrete Fourier transforms (DFT) is found. A method of analysing the multi-dimensional data by their single one-dimensional (1-D) DFT is offered. An experiment of filtering a two-dimensional image using the single 1-D DFT is carried out.

Arthur W. Apter, Joel David Hamkins

We summarize the known methods of producing a non-supercompact strongly compact cardinal and describe some new variants. Our Main Theorem shows how to apply these methods to many cardinals simultaneously and exactly control which cardinals are supercompact and which are only strongly compact in a forcing extension. Depending upon the method, the surviving no

Norbert A'Campo

A new construction of the real number system, that is built directly upon the additive group of integers and has its roots in the definition due to Henri Poincaré of the rotation number of an orientation preserving homeomorphism of the circle.

John R. Klein

For a 1-connected spectrum E, we study the moduli space of suspension spectra which come equipped with a weak equivalence to E. We construct a spectral sequence converging to the homotopy of the moduli space in positive degrees. In the metastable range, we get a complete homotopical classification of the path components of the moduli space. Our main tool is

Flaminio Flamini

The main purpose of this paper is to introduce a new approach to study families of nodal curves on projective threefolds. Precisely, given $X$ a smooth projective threefold, $\E$ a rank-two vector bundle on $X$, $L$ a very ample line bundle on $X$ and $k \geq 0$, $δ>0 $ integers and denoted by $V= {\V}_δ ({\E} \otimes L^{\otimes k})$ the subscheme of ${\Pp}(

Jian-zu Zhang

The non-perturbation and perturbation structures of the q-deformed probability currents are studied. According to two ways of realizing the q-deformed Heisenberg algebra by the undeformed operators, the perturbation structures of two q-deformed probability currents are explored in detail. Locally the structures of two perturbation q-deformed probability curr

Bobby S Acharya

We study M theory compactifications on manifolds of $G_2$-holonomy with gauge and matter fields supported at singularities. We show that, under certain topological conditions, the combination of background $G$-flux and background fields at the singularities induces a potential for the moduli with an isolated minimum. The theory in the minimum is supersymmetr

Kazuhiro Tobe, James D. Wells

Third family Yukawa unification, as suggested by minimal SO(10) unification, is revisited in light of recent experimental measurements and theoretical progress. We characterize unification in a semi-model-independent fashion, and conclude that finite $b$ quark mass corrections from superpartners must be nonzero, but much smaller than naively would be expecte

V. Del Duca, W. Kilgore, C. Oleari, C. R. Schmidt

In this paper, we analyze the high-energy limits for Higgs boson plus two jet production. We consider two high-energy limits, corresponding to two different kinematic regions: a) the Higgs boson is centrally located in rapidity between the two jets, and very far from either jet; b) the Higgs boson is close to one jet in rapidity, and both of these are very f

T. A. Lahde

The electromagnetic and pionic transitions in mesons with heavy flavor quarks are calculated within the framework of the covariant Blankenbecler-Sugar equation. The M1 transitions in the charmonium system are shown to be sensitive to the relativistic aspect of the spin-flip magnetic moment operator, and the Lorentz structure of the Q\bar Q interaction. The o

J. A. R. Cembranos, A. Dobado, A. L. Maroto

The recent proposal of theories with compactified large extra dimensions is reviewed. We pay especial attention to brane world models with low tension where the only relevant degrees of freedom at low energies are the Standard Model (SM) particles and the branons, which are transversal brane oscillations. By using an effective Lagrangian, we study some pheno

Mannque Rho

The role of effective degrees of freedom on the vector and axial-vector susceptibilities and the pion velocity at chiral restoration is analyzed. We consider two possible scenarios, one in which pions are considered to be the only low-lying degrees of freedom -- that we shall refer to as "standard" -- and the other in which pions, vector mesons and c

M. W. Choptuik, E. W. Hirschmann, S. L. Liebling, F. Pretorius

We present a new numerical code designed to solve the Einstein field equations for axisymmetric spacetimes. The long term goal of this project is to construct a code that will be capable of studying many problems of interest in axisymmetry, including gravitational collapse, critical phenomena, investigations of cosmic censorship, and head-on black hole colli

P. M. Valanju, R. M. Walser, A. P. Valanju

VWV's inhomogeneous wave solution to Maxwell equations in NIM are correct. In NIM, the modulations do not propagate along the Poynting vector.

D. H. J. O'Dell, S. Giovanazzi, G. Kurizki

A gaseous Bose-Einstein condensate (BEC) irradiated by a far off-resonance laser has long-range interatomic correlations caused by laser-induced dipole-dipole interactions. These correlations, which are tunable via the laser intensity and frequency, can produce a `roton' minimum in the excitation spectrum--behavior reminiscent of the strongly correlated

F. Ronning, T. Sasagawa, Y. Kohsaka, K. M. Shen

We present angle resolved photoemission (ARPES) data on Na-doped Ca$_2$CuO$_2$Cl$_2$. We demonstrate that the chemical potential shifts upon doping the system across the insulator to metal transition. The resulting low energy spectra reveal a gap structure which appears to deviate from the canonical $d_{x2-y2} ~ |cos(k_x a)-cos(k_y a)|$ form. To reconcile th

P. Pieri, G. C. Strinati

We derive the time-independent Gross-Pitaevskii equation at zero temperature for condensed bosons, which form as bound-fermion pairs when the mutual fermionic attractive interaction is sufficiently strong, from the strong-coupling limit of the Bogoliubov-de Gennes equations that describe superfluid fermions in the presence of an external potential. Three-bod

C. M. Newman, D. L. Stein

We discuss the underlying connections among the thermodynamic properties of short-ranged spin glasses, their behavior in large finite volumes, and the interfaces that separate different pure states, and also ground states and low-lying excitations.

P. G. Kevrekidis, S. K. Kumar, I. G. Kevrekidis

We propose a connection between self-similar, focusing dynamics in nonlinear partial differential equations (PDEs) and macroscopic dynamic features of the glass transition. In particular, we explore the divergence of the appropriate relaxation times in the case of hard spheres as the limit of random close packing is approached. We illustrate the analogy in t

Vidar Gudmundsson, Chi-Shung Tang, Andrei Manolescu

We consider a model of a semiconductor quantum ring of finite width in a constant perpendicular magnetic field. We show how a current of the same order as the persistent current can be generated non-adiabatically by a short intensive pulse in the Tera-Hertz regime.

John H. Debes, Jian Ge

Gaussian aperture pupil masks (GAPMs) can in theory achieve the contrast requisite for directly imaging an extrasolar planet. We use lab tests and simulations to further study their possible place as a high contrast imaging technique. We present lab comparisons with traditional Lyot coronagraphs and simulations of GAPMs and other high contrast imaging techni

A. J. R. Sanderson, T. J. Ponman, A. Finoguenov, E. J. Lloyd-Davies

We have assembled a large sample of virialized systems, comprising 66 galaxy clusters, groups and elliptical galaxies with high quality X-ray data. To each system we have fitted analytical profiles describing the gas density and temperature variation with radius, corrected for the effects of central gas cooling. We present an analysis of the scaling properti

David T. Chuss, Giles Novak, Roger H. Hildebrand, C. Darren Dowell

We report the detection of polarized emission in the vicinity of the Galactic center for 158 positions within eight different pointings of the Hertz polarimeter operating on the Caltech Submillimeter Observatory. These pointings include positions 2 arcminutes offset to the E, NE, and NW of M-0.02-0.07; positions to the SE and NW of the 20 km/s cloud (M-0.13-

Bahram Mobasher, Matthew Colless, David Carter, Bianca Poggianti

A large spectroscopic survey is constructed of galaxies in the Coma cluster. The survey covers a wide area (1 deg$^2$) to deep magnitudes (R ~ 19.5), covering both the core (high density) and outskirts (intermediate to low density) of the cluster. The spectroscopic sample consists of a total of 1191 galaxies, of which, 760 galaxies are confirmed members of t

Christopher L. Taylor, Q. Daniel Wang

We study the nature and the origin of the dust arch in the halo of the edge-on galaxy NGC 4631 detected by Neininger & Dumke (1999). We present CO observations made using the new On-The-Fly mapping mode with the FCRAO 14m telescope, and find no evidence for CO emission associated with the dust arch. Our examination of previously published HI data shows that

Charles R. Cowley, Manuel Bautista

We discuss implementation of TOPbase and Iron Project opacities for stellar spectral codes. We use a technique employed by Peach, where a Boltzmann-averaged cross section is calculated for selected temperatures, and the opacity obtained from double interpolation in temperature and wavelength. It is straightforward to include {\it all} levels for which cross

K. O'Neil, E. Schinnerer, P. Hofner

Using the IRAM 30m telescope we have obtained seven new, deep CO J(1-0) and J(2-1) observations of low surface brightness (LSB) galaxies. Five of the galaxies have no CO detected to extremely low limits (0.1-0.4 K km/s at J(1-0)), while two of the galaxies, UGC 01922 and UGC 12289, have clear detections in both line transitions. When these observations are c

Nikos Prantzos

After summarizing the most important features of current stellar yields of CNO elements (including recent results concerning rotating and mass losing stars) I discuss how these yields may help to interpret relevant observations in the local Galaxy, the Milky Way disk and extragalactic systems (extragalactic HII regions and DLAs).

J. A. Peacock

The 2dF Galaxy Redshift Survey is the first to observe more than 100,000 redshifts, making possible precise measurements of many aspects of galaxy clustering. The spatial distribution of galaxies can be studied as a function of galaxy spectral type, and also of broad-band colour. Redshift-space distortions are detected with a high degree of significance, con

Simon Portegies Zwart, Piet Hut, Steve McMillan, Jun Makino

We have modeled in detail the evolution of rich open star clusters such as the Pleiades, Praesepe and Hyades, using simulations that include stellar dynamics as well as the effects of stellar evolution. The dynamics is modeled via direct N-body integration, while the evolution of single stars and binaries is followed through the use of fitting formulae and r

Guenther Hasinger

First indications of the warm/hot intergalactic medium, tracing out the large scale structure of the universe, have been obtained in sensitive Chandra and XMM-Newton high resolution absorption line spectroscopy of bright blazars. High resolution X-ray spectroscopy and imaging also provides important new constraints on the physical condition of the cooling ma

Ian R. Stevens, Joanna M. Hartwell

Results of a study of the theoretically predicted and observed X-ray properties of local massive star clusters are presented, with a focus on understanding the mass and energy flow from these clusters into the ISM via a cluster wind. A simple theoretical model, based on the work of Chevalier & Clegg (1985), is used to predict the theoretical cluster properti

D. Nogami, H. Baba, K. Matsumoto, T. Kato

We carried out time-resolved $V$-band photometry of DM Lyr during long outbursts in 1996 July and in 1996 February-March at Ouda Station, Kyoto University and at Osaka Kyoiku University. Since superhumps were clearly detected in the light curves, DM Lyr was first identified with an SU UMa-type dwarf nova. The superhump period is 0.0673(2) d, and the superhum

Chenggang Shu, H. J. Mo, Shude Mao

Galactic winds and mass outflows are observed both in nearby starburst galaxies and in high-redshift star-forming galaxies. In this paper we develop a simple analytic model to understand the observed superwind phenomenon. Our model is built upon the model of McKee & Ostriker (1977) for the interstellar medium. It allows one to predict how properties of a sup

Jean-Pierre Eckmann, Esa Järvenpää, Maarit Järvenpää, Itamar Procaccia

Estimates of the fractal dimension $D$ of the set of galaxies in the universe, based on ever improving data sets, tend to settle on $D\approx 2$. This result raised a raging debate due to its glaring contradiction with astrophysical models that expect a homogeneous universe. A recent mathematical result indicates that there is no contradiction, since measure

Joshua S. Bloom

The various possibilities for the progenitors of gamma-ray bursts (GRBs) manifest in differing observable properties. Through deep spectroscopic and high-resolution imaging observations of some GRB hosts, I demonstrate that well-localized long-duration GRBs are connected with otherwise normal star-forming galaxies at moderate redshifts of order unity. I test

Charles D. Dermer, Armen Atoyan

We treat high-energy neutrino production in GRBs. Detailed calculations of photomeson neutrino production are presented for the collapsar model, where internal nonthermal synchrotron radiation is the primary target photon field, and the supranova model, where external pulsar-wind synchrotron radiation provides important additional target photons. Detection o

Brian Yanny, Heidi Jo Newberg, Eva K. Grebel, Steve Kent

We present evidence for a ring of stars in the plane of the Milky Way, extending at least from l = 180 deg to l = 227 deg with turnoff magnitude $g \sim 19.5$; the ring could encircle the Galaxy. We infer that the low Galactic latitude structure is at a fairly constant distance of R = 18 +/- 2 kpc from the Galactic Center above the Galactic plane, and has R

V. R. Shaginyan

The behavior in magnetic fields of a highly correlated electron liquid approaching the fermion condensation quantum phase transition from the disordered phase is considered. We show that at sufficiently high temperatures $T\geq T^*(x)$ the effective mass starts to depend on $T$, $M^*\propto T^{-1/2}$. This $T^{-1/2}$ dependence of the effective mass at eleva

Alex G. Muslimov, Alice K. Harding

We revise the physics of primary electron acceleration in the "slot gap" (SG) above the pulsar polar caps (PCs), a regime originally proposed by Arons and Scharlemann (1979) in their electrodynamic model of pulsar PCs. We employ the standard definition of the SG as a pair-free space between the last open field lines and the boundary of the pair plasm