December 2001 arXiv papers — page 23

G. Dubner, E. Giacani, B. M. Gaensler, W. M. Goss

We report on Australia Telescope Compact Array (ATCA) HI observations carried out in the direction of bilateral supernova remnants (SNRs) with associated neutron stars: G296.5+10.0 and G320.4--1.2, in a search for the origin of such morphology. From these studies we conclude that in the case of G296.5+10.0, located far from the Galactic plane, the HI distrib

Wei Cui, Yuxin Feng, Mark Ertmer

Recent monitoring of Cyg X-1 with {\em RXTE} revealed a period of intense flaring, which started in October of 2000 and lasted until March of 2001. The source exhibited some quite unusual behaviors during this period. The soft X-ray flux of the source went up and down three times on a timescale of about one month, as discovered by the ASM aboard RXTE, before

R. A. Bernstein, W. L. Freedman, B. F. Madore

(Abridged) We present the first detections of the mean flux of the optical extragalactic background light (EBL) at 3000, 5500, and 8000A. Diffuse foreground flux at these wavelengths comes from terrestrial airglow, dust-scattered sunlight (zodiacal light), and dust-scattered Galactic starlight (diffuse Galactic light). We have avoided the brightest of these,

S. Mereghetti, A. Pellizzoni, A. De Luca

We present optical observations of the fields of two X-ray sources located near the center of the shell-like supernova remnant G266.1-1.2. No objects brighter than R~22.5 and B~23 are present within the small Chandra error region of AX J0851.9-4617.4, besides a R~17 star that has already been excluded as a possible counterpart. A bright diffuse H_alpha nebul

A. Capetti, A. Celotti, M. Chiaberge, H. R. de Ruiter

We examine the optical properties of the nuclei of low luminosity radio-galaxies using snapshot HST images of the B2 sample. In agreement with the results obtained from the analysis of the brighter 3C/FRI sample, we find a correlation between fluxes (and luminosities) of the optical and radio cores. This provides further support for the interpretation that t

Dinshaw Balsara

In this paper we present a full-fledged scheme for the second order accurate, divergence-free evolution of vector fields on an adaptive mesh refinement (AMR) hierarchy. We focus here on adaptive mesh MHD. The scheme is based on making a significant advance in the divergence-free reconstruction of vector fields. In that sense, it complements the earlier work

C. Baccigalupi, A. Balbi, S. Matarrese, F. Perrotta

We give a brief review of the physics of acoustic oscillations in Cosmic Microwave Background (CMB) anisotropies. As an example of the impact of their detection in cosmology, we show how the present data on CMB angular power spectrum on sub-degree scales can be used to constrain dark energy cosmological models.

Dinshaw Balsara

The advent of robust, reliable and accurate higher order Godunov schemes for many of the systems of equations of interest in computational astrophysics has made it important to understand how to solve them in multi-scale fashion. This is so because the physics associated with astrophysical phenomena evolves in multi-scale fashion and we wish to arrive at a m

A. Mazure, H. V. Capelato

Using the Mathematica package, we find exact analytical expressions for the so-called de-projected De Vaucouleurs and Sersic laws as well as for related spatial (3D) quantities, such the mass, gravitational potential, the total energy and the central velocity dispersion, generally involved in astronomical calculations expressed in terms of the Meijer G funct

Nikita Salvi, Gavin Ramsay, Mark Cropper, D. A. H. Buckley

We present spectroscopic and high speed photometric data of the eclipsing polar V895 Cen. We find that the eclipsed component is consistent with it being the accretion regions on the white dwarf. This is in contrast to Stobie et al who concluded that the eclipsed component was not the white dwarf. Further, we find no evidence for an accretion disc in our dat

Alejandro Gangui, Levon Pogosian, Serge Winitzki

We briefly review certain aspects of cosmic microwave background anisotropies as generated in passive and active models of structure formation. We then focus on cosmic strings based models and discuss their status in the light of current high-resolution observations from the BOOMERanG, MAXIMA and DASI collaborations. Upcoming megapixel experiments will have

O. V. Verkhodanov, Yu. N. Parijskij, N. S. Soboleva, A. I. Kopylov

About 100 steep spectrum radio sources from the RATAN--600 RC catalog were mapped by the VLA and identified with optical objects down to 24$^m$--25$^m$ in the R band using the 6 m telescope. An updated list of calibrators with known redshifts of the same class RGs was compiled to evaluate the accuracy of photometric redshifts estimates. BVRI photometry for 6

Oleg V. Verkhodanov, Natalia V. Verkhodanova, Heinz Andernach

Radio sources from the decametric UTR--2 catalog were cross-identified with other radio catalogs at higher frequencies. We used the CATS database to extract all sources within the UTR beam size ($\sim40'$) to find candidate radio identifications. Using the least squares method we fitted the spectrum of each source with one of a set of curves. We extracte

O. V. Verkhodanov, A. I. Kopylov, N. V. Verkhodanova, O. P. Zhelenkova

The system allowing a user to operate with simulated curves of spectral energy distribution (SED) and to estimate ages and redshifts by photometric data at server {\bf sed.sao.ru} is described.

J. C. Baker, R. W. Hunstead, R. M. Athreya, P. D. Barthel

We assess the global properties of associated C IV 1548,1550 absorption lines measured in the spectra of radio-loud quasars drawn from a near-complete, low-frequency selected sample. The observations span restframe C IV in two redshift ranges -- 0.7<z<1.0 and 1.5<z<3.0 -- which were targetted in the UV with HST/STIS and in the optical with ground-based teles

O. V. Verkhodanov, V. H. Chavushyan, R. Mújica, J. R. Valdés

The steep spectrum of IRAS F02044+0957 was obtained with the RATAN-600 radio telescope at four frequencies. Optical spectroscopy of the system components, was carried out with the 2.1m telescope of the Guillermo Haro Observatory. Observational data allow us to conclude that this object is a pair of interacting galaxies, a LINER and a HII galaxy, at $z=0.093$

C. Brocksopp, R. P. Fender, M. McCollough, G. G. Pooley

We have studied the 1999 soft X-ray transient outburst of XTE J1859+226 at radio and X-ray wavelengths. The event was characterised by strong variability in the disc, corona and jet - in particular, a number of radio flares (ejections) took place and seemed well-correlated with hard X-ray events. Apparently unusual for the `canonical soft&#39; X-ray transien

Sudip Bhattacharyya, Dipankar Bhattacharya, Ranjeev Misra, Arun V. Thampan

We compute spectra from accretion disks around rapidly rotating neutron stars. The full effect of general relativity is considered for the structure calculation of the stars. We take into account the Doppler shift, gravitational redshift and light-bending effects in order to compute the observed spectra. To facilitate direct comparison with observations, a s

Sara L. Ellison, Lin Yan, Isobel M. Hook, Max Pettini

We present a list of z_abs ~ z_em (Delta v < 3000 km/s) DLAs discovered during the CORALS survey for absorbers in a radio-selected QSO sample. On the assumption that z_abs ~ z_em DLAs are neither ejecta from the QSO, nor part of the host galaxy itself, we use the number density statistics of these DLAs to investigate galaxy clustering near the QSO redshift.

M. Ostrowski

This report covers the studies of energetic particle propagation and acceleration presented during the 27th ICRC in sessions OG 1.3 and 1.4, plus a few selected papers from neighbouring OG sections. We list problems discussed within these sections and we shortly describe selected interesting achievements and/or novel approaches.

Carlo Nipoti, Pasquale Londrillo, Luca Ciotti

We present preliminary results of numerical simulations of dissipationless merging of stellar systems, aimed at exploring the consequences of merging between gas free, spheroidal systems. In particular, we study the dynamical and structural characteristics of hierarchical merging between equal mass stellar systems, and we compare the properties of the end-pr

Yasushi Ikebe

Central cool gas component that is often observed from a well-relaxed cluster system has long been interpreted as a consequence of ``Cooling Flow&#39;&#39; (CF), radiative cooling followed by inflow of Intra-Cluster Medium (ICM). However, recent XMM-Newton spectroscopy has shown no signatures of cooler gas phases below certain temperatures in typical CF clus

Luca Ciotti, Zoltan Haiman, Jeremiah P. Ostriker

We present a robust method to derive the duty cycle of QSO activity based on the empirical QSO luminosity function and on the present-day linear relation between the masses of supermassive black holes and those of their spheroidal host stellar systems. It is found that the duty cycle is substantially less than unity, with characteristic values in the range $

V. Castellani, S. Degl&#39;Innocenti, M. Marconi

We present a theoretical approach to infer information about RR Lyrae variables from the morphology of their light curves. The method, already successfully applied to the field first overtone variable U Comae, is now tested on a RR$_{\mathrm ab}$ variable in the globular cluster $ω$ Cen. We show that, with this method, it could be possible to give an estimat

H. J. Buttery, G. Cotter, R. W. Hunstead, E. M. Sadler

Statistical overdensities of radio sources in the NRAO VLA Sky Survey (NVSS) catalogue have proven to be signposts to high-redshift clusters of galaxies. A similar search for overdensities has been carried out in the Sydney University Molonglo Sky Survey (SUMSS), which is closely matched in resolution and frequency to the NVSS. Sixty potential southern-hemis

Thomas G. Pannuti, Nebojsa Duric, Christina Lacey, Annette M. N. Ferguson

We present a multi-wavelength study of the properties of supernova remnants (SNRs) in the nearby Sculptor Group Sd galaxy NGC 7793. Using our own Very Large Array radio observations at 6 and 20 cm, as well as archived ROSAT X-ray data, previously published optical results and our own H-alpha image, we have searched for X-ray and radio counterparts to previou

C. O. Heinke, J. E. Grindlay, D. A. Lloyd, P. D. Edmonds

We report spectral and variability analysis of two quiescent low mass x-ray binaries (previously identified with ROSAT HRI as X5 and X7) in the globular cluster 47 Tuc, from a Chandra ACIS-I observation. X5 demonstrates sharp eclipses with an 8.666+-0.008 hr period, as well as dips showing an increased N_H column. Their thermal spectra are well-modelled by u

HongSheng Zhao

We simulate the result of orbital decay for a dwarf satellite galaxy in a disk galaxy potential. The peeling-off of the satellite by the strong tidal field within the disk of the host galaxy quickly reduces the satellite&#39;s mass, and drastically slows down the decaying of the orbit. The result is generally a cluster on a large halo orbit, like the M54 clu

D. Mancini, P. Schipani, O. Caputi, G. Mancini

The VIRMOS consortium of French and Italian Institutes (PI: O. Le Fevre, co-PI: G. Vettolani) is manufacturing two wide field imaging multi-object spectrographs for the European Southern Observatory Very Large Telescope (VLT), with emphasis on the ability to carry over spectroscopic surveys of large numbers of sources: the VIsible Multi-Object Spectrograph,

D. Mancini, P. Schipani, G. Mazzola, L. Marty

The VST (VLT Survey Telescope) is a 2.6 m class Alt-Az telescope to be installed at Mount Paranal in the Atacama desert, Chile, in the European Southern Observatory (ESO) site. The VST is a wide-field imaging facility planned to supply databases for the ESO Very Large Telescope (VLT) science and carry out stand-alone observations in the UV to I spectral rang

P. Schipani, M. Brescia, D. Mancini, L. Marty

The VST (VLT Survey Telescope) is a 2.6 m Alt-Az telescope to be installed at Mount Paranal in Chile, in the European Southern Observatory (ESO) site. The VST is a wide-field imaging facility planned to supply databases for the ESO Very Large Telescope (VLT) science and carry out stand-alone observations in the UV to I spectral range. This paper will focus m

D. A. Demir, M. Shifman

We outline a toy model in which a unique mechanism may trigger a dynamical chain resulting in key low-energy regularities. The starting points are a negative cosmological term in the bulk and conformally invariant nongravity sector. These elements ensure compactification of the extra dimensional space on a compact hyperbolic manifold (with the negative and c

Bing Zhang, Peter Meszaros

We consider a gamma-ray burst (GRB) model based on an anisotropic fireball with an axisymmetric power-law distribution of the energy per solid angle with index -k, and allow for the observer&#39;s viewing direction being at an arbitrary angle with respect to the jet axis. This model can reproduce the key features expected from the conventional on-axis unifor

S. Descotes, N. H. Fuchs, L. Girlanda, J. Stern

The recently published E865 data on charged K_e4 decays and Pi-Pi phases are reanalyzed to extract values of the two S-wave scattering lengths, of the subthreshold parameters alpha and beta, of the low-energy constants l3-bar and l4-bar as well as of the main two-flavour order parameters: <u-bar u> and F_pi in the limit m_u = m_d = 0 taken at the physical va

Antonio Trovato, Jesper Ferkinghoff-Borg, Mogens H. Jensen

We propose an off-lattice model for a self-avoiding homopolymer chain with two different competing attractive interactions, mimicking the hydrophobic effect and the hydrogen bond formation respectively. By means of Monte Carlo simulations, we are able to trace out the complete phase diagram for different values of the relative strength of the two competing i

E. Lytvynov

The aim of this paper is to show that fermion and boson random point processes naturally appear from representations of CAR and CCR which correspond to gauge invariant generalized free states (also called quasi-free states). We consider particle density operators $ρ(x)$, $x\in\R^d$, in the representation of CAR describing an infinite free Fermi gas of finite

S. L. Bridle, R. Crittenden, A. Melchiorri, M. P. Hobson

With the increased accuracy and angular scale coverage of the recent CMB experiments it has become important to include calibration and beam uncertainties when estimating cosmological parameters. This requires an integration over possible values of the calibration and beam size, which can be done numerically but increases computation times. We present a fast

S. C. Badescu, P. Salo, T. Ala-Nissila, S. C. Ying

We present a combination of theoretical calculations and experiments for the low-lying vibrational excitations of H and D atoms adsorbed on the Pt(111) surface. The vibrational band states are calculated based on the full three-dimensional adiabatic potential energy surface obtained from first principles calculations. For coverages less than three quarters o

Lilia Boeri, Giovanni B. Bachelet, Emmanuele Cappelluti, Luciano Pietronero

The remarkable anharmonicity of the E_{2g} phonon in MgB_2 has been suggested in literature to play a primary role in its superconducting pairing. We investigate, by means of LDA calculations, the microscopic origin of such an anharmonicity in MgB_2, AlB_2, and in hole-doped graphite. We find that the anharmonic character of the E_{2g} phonon is essentially

Aigen Li, B. T. Draine

The infrared (IR) emission from interstellar dust in the Small Magellanic Cloud (SMC) is modelled using a mixture of amorphous silicate and carbonaceous grains, including a population of polycyclic aromatic hydrocarbon (PAH) molecules. (1) It is shown that this dust model is able to reproduce the spectral energy distribution from near-IR to far-IR for the en

D. V. Gal&#39;tsov

Recent progress in the study of solitons and black holes in non-Abelian field theories coupled to gravity is reviewed. New topics include gravitational binding of monopoles, black holes with non-trivial topology, Lue-Weinberg bifurcation, asymptotically AdS lumps, solutions to the Freedman-Schwarz model with applications to holography, non-Abelian Born-Infel

D. A. Trifonov

A survey on the generalizations of Heisenberg uncertainty relation and a general scheme for their entangled extensions to several states and observables is presented. The scheme is illustrated on the examples of one and two states and canonical quantum observables, and spin and quasi-spin components. Several new uncertainty relations are displayed. PACS 0365

Masafumi Fukuma, So Matsuura

Classical higher-derivative gravity is investigated in the context of the holographic renormalization group (RG). We parametrize the Euclidean time such that one step of time evolution in (d+1)-dimensional bulk gravity can be directly interpreted as that of block spin transformation of the d-dimensional boundary field theory. This parametrization simplifies

Stephane Peigne, Francesco Sannino

We explain why contrary to common belief, the deep inelastic scattering structure functions are not related to parton probabilities in the target.

Ding-Yu Chung

In this paper, the evolution of galaxies is by the incompatibility between dark matter and baryonic matter. Due to the structural difference, baryonic matter and dark matter are incompatible to each other as oil droplet and water in emulsion. In the interfacial zone between dark matter and baryonic matter, this incompatibility generates the modification of N

Wolf P. Barth, Slawomir Rams

Let Y be a surface with only finitely many singularities all of which are cusps. A set of cusps on Y is called three-divisible, if there is a cyclic global triple cover of Y branched precisely over these cusps. The aim of this note is to determine the equations of surfaces $Y \subset P_3$ of degrees $\leq 6$ carrying a minimal, non-empty, three-divisible set

Kyrill A. Bugaev

A popular derivation of the apparent temperature of the particle transverse momentum spectra and its inconsistency are considered. An improved formula for the apparent temperature is discussed. It is shown that recent results on transverse mass spectra of $J/ψ$ and $ψ^{\prime}$ mesons support a hypothesis of statistical production of charmonia at hadronizati

D. Bar, L. P. Horwitz

We discuss the properties of a large number N of one-dimensional (bounded) locally periodic potential barriers in a finite interval. We show that the transmission coefficient, the scattering cross section $σ$, and the resonances of $σ$ depend sensitively upon the ratio of the total spacing to the total barrier width. We also show that a time dependent wave p

Xiao-Jun Bi, Yuan-Ben Dai

The tiny neutrino masses measured in the neutrino oscillation experiments can be naturally explained by the supersymmetric see-saw mechanism. If the supersymmetry breaking is mediated by gravity, the see-saw models may predict observable lepton flavor violating effects. In this work, we investigate the lepton flavor violating process $μ\to eγ$ in the kind of

H. J. Mo, S. Mao

We outline a scenario of galaxy formation in which the gas in galaxy-forming regions was preheated to high entropy by vigorous energy feedback associated with the formation of stars in old ellipticals and bulges and with AGN activity. Such preheating likely occurred at redshifts z ~ 2-3, and can produce the entropy excess observed today in low-mass clusters

S. Drenska, A. Georgieva, N. Minkov

We implement a high order discrete derivative analysis of the low lying collective energies of even-even nuclei with respect to the total number of valence nucleon pairs N in the framework of F- spin multiplets appearing in a symplectic sp(4,R) classification scheme. We find that for the nuclei of any given F- multiplet the respective experimental energies e

Jian Hu, R. X. Xu

The surface electric characteristics of bare strange stars are investigated with the inclusion of boundary effects. The thickness of the electron layer where pairs can be spontaneously created is calculated as a function of the bag parameters. We find that previous estimates are representative for bag parameters within a rather wide range, and therefore our

HongSheng Zhao, Martin G. Haehnelt, Martin J. Rees

We estimate the rate at which stars are captured by supermassive black holes (BHs) in the centres of bulges and elliptical galaxies assuming that these initially had an isothermal cusp (rho ~ r^{-2} with velocity dispersion sigma_*). If radial orbits can be adequately replenished a BH can grow significantly by capturing stars and particles of the dark halo;

Frank Zielen, Andreas Schadschneider

We introduce a variant of the asymmetric random average process with continuous state variables where the maximal transport is restricted by a cutoff. For periodic boundary conditions, we show the existence of a phase transition between a pure high flow phase and a mixed phase, whereby the latter consists of a homogeneous high flow and a condensed low flow s

P. Valageas

We investigate the error implied by the use of the Zel&#39;dovich approximation to set up the initial conditions at a finite redshift zi in numerical simulations. Using a steepest-descent method developed in a previous work we derive the probability distribution P(delta_R) of the density contrast in the quasi-linear regime. This also provides its dependence

Dongsu Bak, Nobuyoshi Ohta

We consider the flat supersymmetric D2 and anti-D2 system, which follows from ordinary noncommutative D2 anti-D2 branes by turning on an appropriate worldvolume electric field describing dissolved fundamental strings. We study the strings stretched between D2 and anti-D2 branes and show explicitly that the would-be tachyonic states become massless. We comput

S. T. Petcov, M. Piai

In the context of three-neutrino oscillations, we study the possibility of using antineutrinos from nuclear reactors to explore the 10^{-4} {\rm eV^2} < \ms \ltap 8\times 10^{-4} {\rm eV^2} region of the LMA MSW solution of the solar neutrino problem and measure $\ms$ with high precision. The KamLAND experiment is not expected to determine $\ms$ if the latte

Jisuke Kubo, Masanori Nunami

Unrenormalizable theories contain infinitely many free parameters. Considering these theories in terms of the Wilsonian renormalization group (RG), we suggest a method for removing this large ambiguity. Our basic assumption is the existence of the maximal ultraviolet cutoff in a cutoff theory, and we require that the theory be so fine-tuned as to reach the m

Xu Kong, Fuzhen Cheng

We apply the method of principal component analysis to a sample of simple stellar populations to select some age-sensitive spectral indices. Besides the well-known age-sensitive index, H B, we find that some other spectral indices have great potential to determine the age of stellar populations, such as G4300, Fe4383, C24668, and Mgb. In addition, we find th

A. D. Alhaidari

The relativistic J-matrix is investigated in the case of Coulomb-free scattering for a general short-range spin-dependent perturbing potential and in two different L2 bases. The resulting recursion relation of the reference problem, in this case, has an analytic solution. The non-relativistic limit is obtained and shown to be identical to the familiar non-re

T. R. Kirkpatrick, D. Belitz

We explain why the objections raised by Golubev et al. in a comment on cond-mat/0111398 are not valid.

A. S. Wilson, Y. Yang

We report X-ray imaging - spectroscopy of the jet of M87 at sub arc second resolution with the Chandra X-ray Observatory. The galaxy nucleus and all the knots seen at radio and optical wavelengths, as far from the nucleus as knot C, are detected in the X-ray observations. There is a strong trend for the ratio of X-ray to radio, or optical, flux to decline wi

Wang Xiang-Bin, Matsumoto Keiji, Fan Heng, Y. Nakamura

The quantum dynamics of the Josephson junction system in the computational subspace is investigated. A scheme for the controlled not operation is given for two capasitively coupled SQUIDs. In this system, there is no systematic error for the two qubit operation. For the inductively coupled SQUIDs, the effective Hamiltonian causes systematic errors in the com

Douglas G. Danforth

Classical systems can be entangled. Entanglement is defined by coincidence correlations. Quantum entanglement experiments can be mimicked by a mechanical system with a single conserved variable and 77.8% conditional efficiency. Experiments are replicated for four particle entanglement swapping and GHZ entanglement.

E. A. Cummings, M. S. Hicken, S. D. Bergeson

We report an injection-locked cw titanium:sapphire ring laser at 846 nm. It produces 1.00 W in a single frequency when pumped with 5.5 W. Single frequency operation requires only a few milliwatts of injected power.

C. Iacobaeus, M. Danielsson, P. Fonte, T. Francke

We have demonstrated experimentally that the main breakdown-triggering mechanism in most gaseous detectors, including micropattern gaseous detectors, is sporadic electron jets from the cathode surfaces. Depending on conditions, each jet contains randomly from a few primary electrons up to 10^5, emitted in a time interval ranging between 0.1 microsecond to mi

George M. Chechin, Olga A. Lavrova, Vladimir P. Sakhnenko, Harold T. Stokes

New type of nonlinear (anharmonic) excitations -- bushes of vibrational modes -- in physical systems with point or space symmetry are discussed. All infrared active and Raman active bushes for C60 fulerene are found by means of special group-theoretical methods.

Andrey Lyalin, Andrey Solov&#39;yov, Walter Greiner

Fission of doubly charged metal clusters is studied using the open-shell two-center deformed jellium Hartree-Fock model and Local Density Approximation. Results of calculations of the electronic structure and fission barriers for the symmetric and asymmetric channels associated with the following processes Na_{10}^{2+} --> Na_{7}^{+} + Na_{3}^{+}, Na_{18}^{2

Li-Bin Fu, Jie Liu, Jing Chen, Shi-Gang Chen

In this paper, a quasistatic model is extended to describe the double ionization of Helium in intense linearly polarized field, yielding achieve an insight to the two-electron correlation effect in the ionization dynamics. Our numerical calculations reproduce the excessive double ionization and the photoelectron spectra observed experimentally both quantitat

Hans Dehmelt

Following Socrates&#39; advice &#34;You should learn all you can from those who know. Everyone should watch himself throughout his life, and notice what sort of meat and drink and what form of exercise suit his constitution, and he should regulate them in order to enjoy good health.&#34; Based on biological, chemical and physical considerations I have attemp

C. M. Chu, J. Galambos, J. Wei, C. K. Allen

The architecture for Spallation Neutron Source accelerator physics application programs is presented. These high level applications involve processing and managing information from the diagnostic instruments, the machine control system, models and static databases; they will be used to investigate and control beam behavior. Primary components include an SNS

Jose B. Almeida

The paper deals with the concepts of mass and gravity in the formalism of 4-dimensional optics, previously introduced by the author. It is shown that elementary particles can be associated with 4-dimensional standing wave patterns with the Compton wavelength and both inertial and gravitational mass are derived from this concept and shown to be attributable t

Piotr Magierski, Paul-Henri Heenen

We investigate the inner crust structure of neutron stars using the Skyrme-Hartree-Fock approach with the Coulomb interaction treated beyond the Wigner-Seitz approximation. Our results suggest that the shell effects associated with unbound neutrons play an important role and, in particular, lead to complicated phase transition pattern between various nuclear

Emmanuel Tannenbaum

This paper presents a PDE-based approach to finding an optimal canonical basis with which to represent a nearly integrable Hamiltonian. The idea behind the method is to continuously deform the initial canonical basis in such a way that the dependence of the Hamiltonian on the canonical position of the final basis is minimized. The final basis incorporates as

M. Bertola, B. Eynard, J. Harnad

The two matrix model is considered, with measure given by the exponential of a sum of polynomials in two different variables. It is shown how to derive a sequence of pairs of ``dual&#39;&#39; finite size systems of ODEs for the corresponding biorthonormal polynomials. An inverse theorem is proved showing how to reconstruct such measures from pairs of semi-in

D. Levi, P. Winternitz

Different symmetry formalisms for difference equations on lattices are reviewed and applied to perform symmetry reduction for both linear and nonlinear partial difference equations. Both Lie point symmetries and generalized symmetries are considered and applied to the discrete heat equation and to the integrable discrete time Toda lattice.

Shigeki Matsutani

Soliton Solutions of Korteweg-de Vries (KdV) were constructed for given degenerate curves $y^2 = (x-c)P(x)^2$ in terms of hyperelliptic sigma functions and explicit Abelian integrals. Connection between sigma functions and tau function were also presented.

Greg W. Anderson

The {\em abeliant} is a polynomial rule for producing an $n$ by $n$ matrix with entries in a given ring from an $n$ by $n$ by $n+2$ array of elements of that ring. The theory of abeliants, first introduced in an earlier paper of the author, is redeveloped here in a simpler way. Then this theory is exploited to give an explicit elementary construction of the

K. R. Goodearl, T. H. Lenagan

A complete determination of the prime ideals invariant under winding automorphisms in the generic 3 by 3 quantum matrix algebra is obtained. Explicit generating sets consisting of quantum minors are given for all of these primes, thus verifying a general conjecture in the 3 by 3 case. The result relies heavily on certain tensor product decompositions for win

Michael L. Carroll

This paper presents a graded hierarchy or chain of binary operations on the reals and the complex numbers. The operations are related distributively in the sense that any one of them distributes over the next lower operation in the chain. For one particular operation we explore specific properties and derive results, including several useful formulas and ide

Michael Nauenberg

During the past 25 years there has been a controversy regarding the adequacy of Newton&#39;s proof of Prop. 1 in Book 1 of the {\it Principia}. This proposition is of central importance because its proof of Kepler&#39;s area law allowed Newton to introduce a geometric measure for time to solve problems in orbital dynamics in the {\it Principia}. It is shown

Salih Celik

In this work, differential geometry of the Z$_3$-graded quantum superplane is constructed. The corresponding quantum Lie superalgebra and its Hopf algebra structure are obtained.

Salih Celik

Differential calculus on the quantum quaternionic group GL(1,H$_q$) is introduced.

Christian Brouder, Alessandra Frabetti

In this paper we describe the Hopf algebras on planar binary trees used to renormalize the Feynman propagators of quantum electrodynamics, and the coaction which describes the renormalization procedure. Both structures are related to some semi-direct coproduct of Hopf algebras.

Michel Matignon

In his Ph. D. thesis, C. Lehr offers an algorithm which gives the stable model for p-cyclic covers of the projective line over a p-adic field under the conditions that the branch locus whose cardinal is m+1 has the so called equidistant geometry and m<p. In this note we give an algorithm also in the equidistant geometry case but without condition on m. In pa

Masahiko Miyamoto

We determined the inner products of two conformal vectors with central charge 1/2 whose τ-involutions generates S_3 if none of τ-involutions are trivial. We also see that a subVA generated by such conformal vectors is a VOA with central charge 1/2+20/21 or $4/5+6/7 and has a Griess algebra of dimension three or four, respectively.

Paolo Aschieri, Francesco Bonechi

We describe noncommutative geometric aspects of twisted deformations, in particular of the spheres in Connes and Landi [8] and in Connes and Dubois Violette [7], by using the differential and integral calculus on these spaces that is covariant under the action of their corresponding quantum symmetry groups. We start from multiparametric deformations of the o

Ciro Ciliberto, Margarida Mendes Lopes

This paper is devoted to the classification of irregular surfaces of general type with $p_g=q=2$ and non birational bicanonical map. The main result is that, if $S$ is such a surface and if $S$ is minimal with no pencil of curves of genus 2, then $S$ is a double cover of a principally polarized abelian surface $(A,Θ)$, with $Θ$ irreducible. The double cover

Julie D. Blum

Nonperturbative corrections in type II string theory corresponding to Riemann surfaces with one boundary are calculated in several noncompact geometries of desingularized orbifolds. One of these models has a complicated phase structure which is explored. A general condition for integrality of the numerical invariants is discussed.

M. Abou-Zeid, H. Samtleben

We study supersymmetric vortex solutions in three-dimensional abelian gauged supergravity. First, we construct the general U(1)-gauged D=3, N=2 supergravity whose scalar sector is an arbitrary Kahler manifold with U(1) isometry. This construction clarifies the connection between local supersymmetry and the specific forms of some scalar potentials previously

Li-Bin Fu, Yi-Shi Duan, Hong Zhang

Based on the gauge potential decomposition theory and the $ϕ$-mapping theory, the topological inner structure of the Chern-Simons-Higgs vortex has been showed in detail. The evolution of CSH vortices is studied from the topological properties of the Higgs scalar field. The vortices are found generating or annihilating at the limit points and encountering, sp

T. Banks, W. Fischler

This paper has been withdrawn.

Jeffrey A. Harvey, David Kutasov, Emil J. Martinec, Gregory Moore

We study condensation of closed string tachyons living on defects, such as orbifold fixed planes and Neveu-Schwarz fivebranes. We argue that the high energy density of localized states decreases in the process of condensation of such tachyons. In some cases this means that $c_{eff}$ decreases along the flow; in others, $c_{eff}$ remains constant and the decr

Masato Ito

We explore the diversity of warped metric function in five-dimensional gravity including a scalar field and a 3-brane. We point out that the form of the function is determined by a parameter introduced here. For a particular value of the parameter, the warped metric function is smooth without having a singularity, and we show that the bulk cosmological const

P. V. Chliapnikov

The production rates of primary vector and P-wave mesons in Z hadronic decays are analysed. The mass dependence of production rates for the bottom, charm, strange charm and three families of the light-flavour mesons is found to be very similar, allowing to relate the relative production rates for mesons with different flavours and, possibly, their masses. Th

Andre Sopczak

The LEP era has brought immense progress in searches for Higgs bosons over the last 12 years which will guide searches at future colliders. The evolution of the Higgs boson mass limits are reviewed with the focus on results from general parameter scans in the Minimal Supersymmetric extension of the Standard Model (MSSM) in contrast to the so-called benchmark

V. M. Braun, A. Lenz, N. Mahnke, E. Stein

We argue that soft non-factorisable terms give a significant contribution to the baryon form factors at intermediate momentum transfers and set up a framework for the calculation of such terms in the light-cone sum rule approach. Among them, contributions of three-quark states with different helicity structure compared to the leading twist prove to be the mo

P. V. Chliapnikov

The ratios of the production rates K*(892)/K, phi/K, rho^0/pi, omega/pi, Delta^{++}/p, Sigma+(1385)/Lambda, Xi^-/Lambda and their x_p dependences obtained from results of the LEP and SLD experiments in Z hadronic decays are analysed. The corresponding ratios for promptly produced mesons are estimated at x_p -> 1. A comparison of the LEP results with those fr

AMANDA Collaboration, J. Ahrens

In the winter season of 2000, the AMANDA (Antarctic Muon And Neutrino Detector Array) detector was completed to its final state. We report on major physics results obtained from the AMANDA-B10 detector, as well as initial results of the full AMANDA-II detector.

Andre Sopczak

The LEP experiments completed data-taking in November 2000. New preliminary combined results of the four LEP experiments ALEPH, DELPHI, L3 and OPAL are presented for various Higgs boson searches.