December 2002 arXiv papers — page 15

Kostas Skenderis, Marika Taylor

In hep-th/0211011 we started a systematic investigation of open strings in the plane wave background. In this paper we continue the analysis by discussing the superalgebras of conserved charges, the spectra of open strings, and the spectra of DBI fluctuations around D-brane embeddings. We also derive the gluing conditions for corresponding boundary states an

Hiromi Kase, Katsusada Morita, Yoshitaka Okumura, Eizou Umezawa

It is argued that the familiar algebra of the non-commutative space-time with $c$-number $θ^{μν}$ is inconsistent from a theoretical point of view. Consistent algebras are obtained by promoting $θ^{μν}$ to an anti-symmetric tensor operator ${\hatθ}^{μν}$. The simplest among them is Doplicher-Fredenhagen-Roberts (DFR) algebra in which the triple commutator am

Nikolay M. Nikolov, Yassen S. Stanev, Ivan T. Todorov

The singular part of the \textit{operator product expansion} (OPE) of a pair of \textit{globally conformal invariant} (GCI) scalar fields $ϕ$ of (integer) dimension $d$ can be written as a sum of the 2-point function of $ϕ$ and $d-1$ bilocal conformal fields $V_ν(x_1, x_2)$ of dimension $(ν, ν)$, $ν= 1, ..., d-1$. As the correlation functions of $ϕ(x)$ are p

V. D. Tsukanov

The equations for the solitons arbitrarily rotating in the ordinary and isotopic space are obtained. The wave functions of the corresponding dynamic states in the quantum case are found. The generalized matrix of the moments of inertia is degenerate for the O(2)-invariant configurations characteristic for the nucleon and delta-isobar. The equation for such c

G. Toledo Sanchez

The possibility that the magnetic dipole moment (MDM) of light charged vector mesons could be measured from radiative processes involving the production (τ\to ρνγ) and decay(ρ\to ππγ) of vector mesons is studied in a model independent way, via the soft-photon approximation. The angular and energy distribution of photons emitted at small angles respect to the

Mario Everaldo de Souza

It is proposed that each quark is composed of two prequarks, called primons. This composition generates a new hypercharge and a new kind of color called supercolor. Such quark composition explains the Kobaiashi-Maskawa matrix elements in terms of selection rules based on the new hypercharge. Also it is shown that the doublet of quarks top/bottom is quite sim

Alexander Kusenko

Future detection of ultrahigh-energy neutrinos will open a new window on physics at center-of-mass energy 10^5 GeV and higher. In particular, observations of neutrino-initiated showers will help test the Standard Model predictions for the neutrino-nucleon cross section.

E. Gamiz, M. Jamin, A. Pich, J. Prades

The mass of the strange quark is determined from SU(3)-breaking effects in the tau hadronic width. Compared to previous analyses, the contributions from scalar and pseudoscalar spectral functions, which suffer from large perturbative corrections, are replaced by phenomenological parametrisations. This leads to a sizeable reduction of the uncertainties in the

G. Belanger, F. Boudjema, A. Pukhov, S. Rosier-Lees

We discuss constraints on SUSY models with non-unified gaugino masses. We concentrate on the slepton/gaugino sector and obtain a lower limit on the neutralino mass combining direct limits, indirect limits as well as relic density measurements.

Jean-Marc Richard

We review the weak-decay and spectroscopy properties of baryons with two charmed quarks. We also present the convergent speculations on exotic mesons $(QQ\bar{q}\bar{q})$ with two heavy quarks and two light antiquarks.

P. Tinyakov, I. Tkachev

We analyze the existing evidence that BL Lacertae objects (BL Lacs) are sources of the highest-energy cosmic rays. We argue that three independent signatures observed in the real data -- (1) improvement of correlations with corrections of trajectories for the Galactic magnetic field; (2) connection between gamma-ray and UHECR emissions; (3) non-uniform distr

D. V. Ahluwalia

We show that Majorana particles belong to the Wigner class of fermions in which the charge conjugation and the parity operators commute, rather than anticommute. Rigorously speaking, Majorana spinors do not satisfy the Dirac equation [a result originally due to M. Kirchbach, which we re-render here]. Instead, they satisfy a different wave equation, which we

N. S. Mankoc Borstnik, C. D. Froggatt, D. Lukman, M. Axenides

The present volume is the collection of contributions by friends of Holger Bech Nielsen for his 60th birthday. Contents: 1.Unified internal space of spins and charges (N. Mankoc Borstnik) 2.Semitopological Q-Rings (M. Axenides) 3.Non-local axial anomalies in the Standard model (D. Melikhov, B. Stech) 4.Could there be a fourth generation? (C.D. Froggatt) 5.An

Yun-Song Piao, Qing-Guo Huang, Xinmin Zhang, Yuan-Zhong Zhang

In this paper, we consider a model of tachyon with a non-minimal coupling to gravity and study its cosmological effects. Regarding inflation we will show that for a specific coupling of tachyon to gravity this model satisfies observations and solves various problems which exist in the single and multi tachyon inflation models.

A. C. Kalloniatis, S. N. Nedelko

QCD vacuum gluon fields are modelled by hyperspherical domains of constant field strength. The pure glue theory confines static quarks. Solutions of the Dirac operator have chirality properties in agreement with lattice results.

F. del Aguila, J. Santiago

We review the low energy limits on Kaluza-Klein excitations in orbifold models. New vector-like quarks, as well as new Z' gauge bosons, can be accommodated with masses observable at large colliders.

S. Zschocke, O. P. Pavlenko, B. Kampfer

Within QCD sum rules at finite baryon density we show the crucial role of four-quark condensates for the in-medium modification of the omega meson spectral function. In particular, such a global property as the sign of the in-medium omega meson mass shift is found to be governed by a parameter which describes the strength of the density dependence of the fou

Qi-Shu Yan, Dong-Sheng Du

We study the renormalization of the nonlinear effective U(1) Lagrangian up to $O(p^4)$ with spontaneous symmetry breaking. The problems of the quartic divergences and of the truncation of infinite divergence tower are addressed. The renormalization group equations of the effective Lagrangian are derived, which make it possible to get the leading logarithm co

S. Willenbrock

The top quark is one of the least well-studied components of the standard model. In these lectures I discuss the expected properties of the top quark, which will be tested at the Fermilab Tevatron and the CERN Large Hadron Collider. I begin with a modern review of the standard model, emphasizing the underlying concepts. I then discuss the role the top quark

Alfred Tang, John W. Norbury

The Lund string fragmentation model is applied in a non-perturbative calculation of the invariant production cross section of pions from proton-proton collisions in the soft pT region. Invariant production cross sections of pions and kaons from proton-proton collisions in the hard pT region are calculated from the Feynman-Field perturbative QCD parton model.

Takumi Doi, Noriyoshi Ishii, Makoto Oka, Hideo Suganuma

We study the quark-gluon mixed condensate g<\bar{q} sigma G q>, which is another chiral order parameter, using the SU(3)c lattice QCD with the Kogut-Susskind(KS) fermion at the quenched level. We generate 100 gauge configurations on the 16^4 lattice with β= 6.0, and measure the mixed condensate at 16 points in each gauge configuration for each current-quark

H. Ichie, V. Bornyakov, T. Streuer, G. Schierholz

We study the abelian color-flux distribution of the three quark system in the maximally abelian gauge on SU(3) lattices. The distribution of the color electric field suggests $Y Ansatz$, which might be interpreted through the dual superconductor picture as the result of the vacuum pressure in the confined phase. In order to clarify the flux structure, we inv

V. Bornyakov, H. Ichie, Y. Koma, Y. Mori

We study the profile of the broken string (flux tube) in the maximally abelian gauge below and above the finite temperature phase transition in full QCD. In the deconfinement phase, the flux tube disappears and the electric field apperas to be Coulomb-like. In the confinement phase, but near $T_c$, at shorter distances a flux tube is formed like at zero temp

D. J. Summers, J. S. Berg, A. A. Garren, R. B. Palmer

A 4600 Hz fast ramping synchrotron is explored as an economical way of accelerating muons from 4 to 20 GeV/c for a neutrino factory. Eddy current losses are minimized by the low machine duty cycle plus thin grain oriented silicon steel laminations and thin copper wires. Combined function magnets with high gradients alternating within single magnets form the

B Collaboration

Inclusive differential cross sections $dσ_{pA}/dx_F$ and $dσ_{pA}/dp_t^2$ for the production of \kzeros, \lambdazero, and \antilambda particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to $\sqrt {s} = 41.6$ GeV in the proton-nucleon system. The ratios of differential cros

Aura Rosca

This work describes the results of the searches for a Higgs boson decaying into gauge bosons carried out by the four LEP collaborations: ALEPH, DELPHI, L3 and OPAL. A lower bound of 109.7 GeV is set at 95% confidence level on the mass of a fermiophobic Higgs boson decaying into photons. This mass limit can be extended by considering the Higgs decay mode into

L. A. T. Bauerdick, E. Borsato, C. Burgard, T. Carli

For the HERA upgrade, the ZEUS experiment has designed and installed a high precision Micro Vertex Detector (MVD) using single sided micro-strip sensors with capacitive charge division. The sensors have a readout pitch of 120 microns, with five intermediate strips (20 micron strip pitch). An extensive test program has been carried out at the DESY-II testbeam

Clifford M. Will

We carry out a covariant calculation of the measurable relativistic effects in an orbiting gyroscope experiment. The experiment, currently known as Gravity Probe B, compares the spin directions of an array of spinning gyroscopes with the optical axis of a telescope, all housed in a spacecraft that rolls about the optical axis. The spacecraft is steered so th

S. G. Ghosh, A. Banerjee

We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by a self-similar higher dimensional Tolman-Bondi space-time. Bound, marginally bound and unbound space-times are analyzed. The degree of inhomogeneity of the collapsing matter necessary to form a naked singularity is given.

Rodrigo B. Almeida, Virgilio A. F. Almeida

Community identification algorithms have been used to enhance the quality of the services perceived by its users. Although algorithms for community have a widespread use in the Web, their application to portals or specific subsets of the Web has not been much studied. In this paper, we propose a technique for local community identification that takes into ac

Sandor P. Fekete, Henk Meijer, Andre Rohe, Walter Tietze

We consider geometric instances of the Maximum Weighted Matching Problem (MWMP) and the Maximum Traveling Salesman Problem (MTSP) with up to 3,000,000 vertices. Making use of a geometric duality relationship between MWMP, MTSP, and the Fermat-Weber-Problem (FWP), we develop a heuristic approach that yields in near-linear time solutions as well as upper bound

A. Kuriyama, C. Providencia, J. da Providencia, Y. Tsue

A possible scheme of q-deformation, which was recently developed by the present authors, is reviewed by stressing the starting idea.

R. A. Ribeiro, S. L. Bud&#39;ko, C. Petrovic, P. C. Canfield

By synthesizing MgB$_{2}$ using boron of different nominal purity we found values of the residual resistivity ratio ($RRR = R(300 K) / R(42 K)$) from 4 to 20, which covers almost all values found in literature. To obtain high values of $RRR$, high purity reagents are necessary. With the isotopically pure boron we obtained the highest $RRR \sim$ 20 for the st

H. Christ, C. P. Search, P. Meystre

We study the dynamics of a beam of fermions diffracted off a density grating formed by fermionic atoms in the limit of a large grating. An exact description of the system in terms of particle-hole operators is developed. We use a combination of analytical and numerical methods to quantitatively explore the Raman-Nath and the Bragg regimes of diffraction. We

V. G. Kogan, S. L. Bud&#39;ko

Data on macroscopic superconducting anisotropy of MgB$_2$ are reviewed. The data are described within a weak coupling two-gaps anisotropic s-wave model of superconductivity. The calculated ratio of the upper critical fields $γ_H=H_{c2,ab}/H_{c2,c}$ increases with decreasing temperature in agreement with available data, whereas the calculated ratio of London

Peter Nalbach, Walter Harrison

The tunneling probability between two leads connected by a molecule, a chain, a film, or a bulk polarizable insulator is investigated within a model of an electron tunneling from lead A to a state higher in energy, describing the barrier, and from there to lead B. To describe the possibility of energy exchange with excitations of the molecule or the insulato

Arnab Mukherjee, Biman Bagchi

The dynamics of contact pair formation between various hydrophobic residues during folding of a model protein Hp-36 is investigated by Brownian dynamics simulation. Hydropathy scale and non-local helix propensity of amino acids are used to model the complex interaction potential. The resulting structure of the model protein mimics the native state of the rea

S. Kolesnik, B. Dabrowski

Alternating current susceptibility and direct current magnetization have been studied for polycrystalline Ca$_{1-x}$Mn$_x$O. On increasing the Mn content, magnetic ordering changes from spin-glass behavior for $0.25 \leqslant x \leqslant 0.4$ to antiferromagnetic order. The paramagnetic/antiferromagnetic transition is of second order for $0.5 \leqslant x \le

Ana M. Rey, P. B. Blakie, Charles W. Clark

We discuss the dynamics of a Bose-Einstein condensate initially loaded into every third site of an optical lattice using a description based upon the discrete nonlinear Schrodinger equation. An analytic solution is developed for the case of a periodic initial condition and is compared with numerical simulations for more general initial configurations. We sho

E. Vecino, A. Martin-Rodero, A. Levy Yeyati

The Josephson transport and the electronic properties of a quantum dot characterized by a single level coupled to superconducting leads is analyzed. Different approximations are used and compared: the mean field approximation, the second order perturbation theory in the Coulomb interaction and the exact diagonalization in the zero band-width limit. The syste

Markus J. Storcz, Frank K. Wilhelm

Solid state quantum bits are promising candidates for the realization of a {\em scalable} quantum computer. However, they are usually strongly limited by decoherence due to the many extra degrees of freedom of a solid state system. We investigate a system of two solid state qubits that are coupled via $σ_z^{(i)} \otimes σ_z^{(j)}$ type of coupling. This kind

A. Morello, F. L. Mettes, F. Luis, J. F. Fernandez

We report the first example of a transition to long-range magnetic order in a purely dipolarly interacting molecular magnet. For the magnetic cluster compound Mn6O4Br4(Et2dbm)6, the anisotropy experienced by the total spin S=12 of each cluster is so small that spin-lattice relaxation remains fast down to the lowest temperatures, thus enabling dipolar order t

Stephane Coulomb, Michel Bauer

We generalize the poissonian evolving random graph model of Bauer and Bernard to deal with arbitrary degree distributions. The motivation comes from biological networks, which are well-known to exhibit non poissonian degree distribution. A node is added at each time step and is connected to the rest of the graph by oriented edges emerging from older nodes. T

J. Sirker, A. Klümper

We describe a modified transfer matrix renormalization group (TMRG) algorithm and apply it to calculate thermodynamic properties of the one-dimensional t-J model. At the supersymmetric point we compare with Bethe ansatz results and make direct connection to conformal field theory (CFT). In particular we study the crossover from the non-universal high T latti

J. Sirker, G. Khaliullin

We study a new version of the one-dimensional spin-orbital model with spins S=1 relevant to cubic vanadates. At small Hund&#39;s coupling J_H we discover dimerization in a pure electronic system solely due to a dynamical spin-orbital coupling. Above a critical value J_H, a uniform ferromagnetic state is stabilized at zero temperature. More surprisingly, we o

R. Micnas, S. Robaszkiewicz, A. Bussmann-Holder

The two component model of coexisting local electron pairs and itinerant fermions coupled via charge exchange mechanism, which mutually induces superconductivity in both subsystems, is discussed. The cases of isotropic s-wave and anisotropic pairing of extended s and d_{x^2-y^2} -wave symmetries are analyzed for a 2D square lattice within the BCS-mean field

Fei Liu, Luru Dai, Tao Xu, Zhong-can Ou-Yang

Because the constant extension ensemble of single chain molecule is not always equivalent with constant force ensemble, a model of double-stranded conformations, as in RNA molecules and $β$-sheets in proteins, with fixed extension constraint is built in this paper. Based on polymer-graph theory and the self-avoiding walks, sequence dependence and excluded-vo

L. Samaj

The model under consideration is a classical 2D Coulomb gas of pointlike positive and negative unit charges, interacting via a logarithmic potential. In the whole stability range of temperatures, the equilibrium statistical mechanics of this fluid is exactly solvable via an equivalence with the integrable 2D sine-Gordon field theory. The exact solution inclu

T. A. Gloor, F. Mila

We revisit the problem of the correlation gap in (n,n) armchair carbon nanotubes, that would be metallic in the absence of electron-electron correlations. We attack the problem in the context of a Hubbard model with on-site repulsion U only, and we show that the scaling of the gap as exp(-nt/U) predicted by Balents and Fisher (Phys. Rev. B 55, R11973 (1997))

R. Moessner, S. L. Sondhi

Motivated by recent interest in 2+1 dimensional quantum dimer models, we revisit Fisher&#39;s mapping of two dimensional Ising models to hardcore dimer models. First, we note that the symmetry breaking transition of the ferromagetic Ising model maps onto a non-symmetry breaking transition in dimer language -- instead it becomes a deconfinement transition for

X. S. Chen, V. Dohm

We calculate finite-size effects of the Gaussian model in a L\times \tilde L^{d-1} box geometry with free boundary conditions in one direction and periodic boundary conditions in d-1 directions for 2<d<4. We also consider film geometry (\tilde L \to \infty). Finite-size scaling is found to be valid for d<3 and d>3 but logarithmic deviations from finite-size

Tae-Hyoung Gimm, Han-Yong Choi

We propose and demonstrate a microscopic way to analyze the frequency-dependent infrared conductivity: extraction of the electron self-energy from the inversion of experimentally measured infrared conductivity through the functional minimization and numerical iterations. The self-energy contains the full information on the coherent and incoherent parts of in

Celia Rogero, Jose-Angel Martin-Gago, Pedro L. de Andres

Surface Patterson Functions have been derived by direct inversion of experimental Low-Energy Electron Diffraction I-V spectra measured at multiple incident angles. The direct inversion is computationally simple and can be used to discriminate between different structural models. 1x1 YSi_2 epitaxial layers grown on Si(111) have been used to illustrate the ana

Indranil Rudra, K. Saito, S. Ramasesha, Seiji Miyashita

The energy structure of the V$_{15}$ is studied using exact diagonalization methods, and the adiabatic changes of the magnetization in the system with the sweeping field are investigated. We confirm that the Dzyaloshinskii-Moriya interaction leads to an energy gap which allows the adiabatic change of the magnetization which has been found experimentally by C

Y. Asano, Y. Tanaka, M. Sigrist, S. Kashiwaya

The Josephson current between an s-wave and a spin-triplet superconductor Sr$_2$RuO$_4$ (SRO) is studied theoretically. In spin-singlet / spin-triplet superconductor junctions, there is no Josephson current proportional to $\sin ϕ$ in the absence of the spin-flip scattering near junction interfaces, where $ϕ$ is a phase-difference across junctions. Thus a do

Hyeong-Chai Jeong, Paul J. Steinhardt

The quasi-unit cell picture describes the atomic structure of quasicrystals in terms of a single, repeating cluster which overlaps neighbors according to specific overlap rules. In this paper, we discuss the precise relationship between a general atomic decoration in the quasi-unit cell picture atomic decorations in the Penrose tiling and in related tiling p

I. Abou Hamad, Th. Wandlowski, G. Brown, P. A. Rikvold

We present chronocoulometry experiments and equilibrium Monte Carlo simulations for the electrosorption of Br and Cl on Ag(100) single-crystal electrode surfaces. Two different methods are used to calculate the long-range part of the adsorbate-adsorbate interactions. The first method is a truncated-sum approach, while the second is a mean-field-enhanced trun

Falk Herwig

The oldest stars hide information about the chemical evolution of the early universe. In this contect new models of the AGB stellar evolution phase at very low and zero metallicity are presented. Due to the deficiency or absence of CNO catalytic material hydrogen burning operates at significantly higher temperatures than in stars of higher metallicity. As a

Jean Eilek, Philip Hardee, Andrei Lobanov

The wealth of high quality data now available on the M87 jet inspired us to carry out a detailed analysis of the plasma physical conditions in the jet. In a companion paper (Lobanov, Hardee & Eilek, this proceedings) we identify a double-helix structure within the jet, and apply Kelvin-Helmholtz stability analysis to determine the physical state of the jet p

Maria Lugaro, Falk Herwig, John C. Lattanzio, Roberto Gallino

[abridged] We study the s-process in AGB stars using three different stellar evolutionary models computed for a 3Msun and solar metallicity star. First we investigate the formation and the efficiency of the main neutron source. We parametrically vary the number of protons mixed from the envelope into the C12 rich core. For p/C12 > 0.3, mainly N14 is produced

J. P. Blakeslee, K. R. Anderson, G. R. Meurer, N. Benitez

We have written an automatic image processing pipeline for the Advanced Camera for Surveys (ACS) Guaranteed Time Observation (GTO) program. The pipeline, known as Apsis, supports the different cameras available on the ACS instrument and is written in Python with a flexible object-oriented design that simplifies the incorporation of new pipeline modules. The

Norbert Przybilla, Rolf-Peter Kudritzki, Keith Butler, Sylvia R. Becker

Accurate atomic data have become available in the recent past due to the demands of astrophysics and fusion research. We report on the impact of such data on non-LTE line-formation calculations for CNO in early-type stars. Considerable improvement is achieved by the derivation of consistent results from practically all available spectroscopic indicators, reg

David A. Tilley, Ralph E. Pudritz, James Wadsley

We performed simulations of self-gravitating hydrodynamic turbulence to model the formation of filaments, clumps and cores in molecular clouds. We find that when the mass on the initial computational grid is comparable to the Jeans mass, turbulent pressure is able to prevent gravitational collapse. When the turbulence has damped away sufficiently, gravitatio

Ofer Lahav

We review the ability of redshift surveys to provide constraints on the Dark Energy content of the Universe. The matter power spectrum and dynamics at the present epoch are nearly `blind&#39; to Dark Energy, but combined with the CMB they can provide a constraint on the Equation of State parameter w. A representative result from the 2dF galaxy redshift surve

David H. Weinberg, Romeel Dav&#39;e, Neal Katz, Lars Hernquist

We investigate galaxy clustering and galaxy-mass correlations in the LCDM cosmological model using a large volume SPH simulation. For the most part, the predicted biases between galaxies and dark matter lead to good agreement with current observations, including: (1) a nearly constant comoving correlation length from z=3 to z=0 for mass-selected galaxy sampl

Juna A. Kollmeier, David H. Weinberg, Romeel Dave&#39;, Neal Katz

Hydrodynamic cosmological simulations predict that the average opacity of the Ly-alpha forest should increase in the neighborhood of galaxies because galaxies form in dense environments. Recent observations (Adelberger et al. 2002) confirm this expectation at large scales, but they show a decrease of absorption at comoving separations Delta_r <~ 1 Mpc/h. We

Charles Danforth, Ravi Sankrit, William Blair, Chris Howk

N66/NGC346 is the largest and brightest HII region in the Small Magellanic Cloud and contains at least one known supernova remnant SNR0057-7226. Optical emission from the remnant is overwhelmed by the bright photoionized emission from the nebula, but the remnant has been detected by way of far ultraviolet absorption lines. Here we present data from the Far U

Patrick Slane

While supernova remnants (SNRs) have long been considered prime candidates as sources of cosmic rays, it is only recently that X-ray observations have identified several shell-type SNRs dominated by nonthermal emission, thus revealing shock-accelerated electrons with energies extending far beyond the typical thermal spectrum. Two of these SNRs have been dete

A. Spagna, C. Cacciari, R. Drimmel, T. Kinman

We present a proper motion survey over about 200 square degrees towards the NGP, based on the material used for the construction of the GSC-II, that we are using to study the vertical structure and kinematics of the Galaxy. In particular, we measured the rotation velocity of the halo up to 10 kpc above the galactic plane traced by a sample of RR Lyræ and BHB

A. Fontana, F. Poli, N. Menci, M. Nonino

We present the results of a VLT and HST imaging survey aimed at the identification of 4.5<z<6 galaxies. In the VLT data, a set of broad and intermediate band filters has been used to select 13 high--$z$ candidates in a Z(AB)<25 catalog, over an area of about 30 arcmin2. Discrimination against lower redshift interlopers (mainly early--type galaxies at high re

D. Carollo, A. Spagna, M. G. Lattanzi, S. T. Hodgkin

The one billion objects in the GSC-II make up a formidable data set for the hunt of peculiar and rare targets such as late type stars, white dwarfs, carbon dwarfs, asteroids, variable stars, etc. Here we present a survey to search for ancient cool white dwarfs, which led to the discovery of several stars with peculiar spectral distributions and extreme physi

K. -H. Kampert

A brief review about the chemical composition of cosmic rays in the energy range 10^15 < E < 10^20 eV is given. While there is convincing evidence for an increasingly heavier composition above the knee, no clear picture has emerged at the highest energies, yet. We discuss implications about the origin of cosmic rays and emphasize systematic differences relat

K. -H. Kampert et al.

The status and capabilities of the KASCADE-Grande extensive air shower experiment are presented. The installation is located at Forschungszentrum Karlsruhe and comprises a large collecting area (0.5 km^2) electromagnetic array (Grande) operated jointly with the existing KASCADE detectors. KASCADE-Grande will cover the primary energy range 10^16 eV < E_0 < 10

Massimo Giovannini

The interplay among the possible variation of gauge coupling and the inflationary dynamics is investigated in a simplified toy model. Depending upon various parameters (scalar mass, curvature scale at the end of inflation and at the onset of the radiation epoch), the two-point function of the magnetic inhomogeneities grows during the de Sitter stage of expan

C. K. Xu, C. J. Lonsdale, D. L. Shupe, A. Franceschini

Phenomenological models for evolution of dusty galaxies and E/S0 galaxies, respectively, are developed to address two major questions concenring galaxy populations in deep infrared (IR) surveys: (1) Do normal late-type galaxies or starburst galaxies (including galaxies with obscured AGNs) dominate among sources in deep IR surveys? (2) How much do E/S0 galaxi

Andisheh Mahdavi

I discuss a new gravitational potential, Phi(r) ~ (r_0^n+r^n)^(-1/n), for modeling the mass distribution of spherical systems. This potential has a finite mass and generates a density profile with adjustable inner slope 2-n. A gas embedded in this potential has hydrostatic temperature and gas density distributions that are elementary functions of n, greatly

E. M. Green, G. Fontaine, M. D. Reed, K. Callerame

During the course of an ongoing CCD monitoring program to investigate low-level light variations in subdwarf B (sdB) stars, we have serendipitously discovered a new class of low amplitude, multimode sdB pulsators with periods of the order of an hour. These periods are more than a factor of ten longer than those of previously known multimode sdB pulsators (EC

Bo Feng, Mingzhe Li

In non-oscillatory (NO) inflationary models, the reheating mechanism was usually based on gravitational particle production or the mechanism of instant preheating. In this paper we introduce the curvaton mechanism into NO models to reheat the universe and generate the curvature perturbation. Specifically we consider the Peebles-Vilenkin quintessential inflat

P. Aliani, V. Antonelli, M. Picariello, E. Torrente-Lujan

An updated analysis of all available neutrino oscillation evidence in Reactor (Kamland, first 145 days of data) and Solar experiments (SK day and night spectra, global rates from Homestake, SAGE and GALLEX) including the $SNO CC$ and $NC$ data is presented. In the framework of two active neutrino oscillations we determine the allowed regions in neutrino para

D. Fargion

EUSO experiment, while monitoring the downward Earth atmosphere layers, may observe among common Ultra High Energy Cosmic Rays, UHECR, also High Energy Neutrino-Induced Showers either blazing upward to the detectors at high (PeVs) energies or at much higher GZK E >= 10^19 eV energies, showering horizontally in air or vertically downward. A small fraction of

Sarmistha Banik, Debades Bandyopadhyay

We investigate first order phase transitions from $β$-equilibrated hadronic matter to color flavor locked quark matter in compact star interior. The hadronic phase including hyperons and Bose-Einstein condensate of $K^-$ mesons is described by the relativistic field theoretical model with density dependent meson-baryon couplings. The early appearance of hype

I. Boztosun, R. S. Mackintosh

We investigate the inelastic coupling interaction by studying its effect on the elastic scattering potential as determined by inverting the elastic scattering $S$-matrix. We first address the effect upon the real and imaginary elastic potentials of including excited states of the target nucleus. We then investigate the effect of a recently introduced novel c

Asish Ganguly

We have generated, using an sl(2,R) formalism, several new classes of quasi-solvable elliptic potentials, which in the appropriate limit go over to the exactly solvable forms. We have obtained exact solutions of the corresponding spectral problems for some real values of the potential parameters. We have also given explicit expressions of the families of ass

Igor Rivin

Motivated by the study of the local extrema of sin(x)/x we define the \emph{Amplitude Modulation} transform of functions defined on (subsets of) the real line. We discuss certain properties of this transform and invert it in some easy cases.

Isidore Fleischer

Functions, uniformly bounded in $BV$ norm in some bounded open set $U$ in $R^n$, are compact in $L_1(U)$. This result is known when $U$ has Lipschitz boundary [EG Th. 4 p. 176], [G 1.19 Th. p. 17], [Z 5.34 Cor. p. 227]; the proof for general $U$ here, after identifying the operator theoretic definition of bounded $BV$ norm with that of the Tonelli variation,

M. Van den Bergh

We give a proof avoiding spectral sequences of Deligne&#39;s decomposition theorem for objects in a triangulated category admitting a Lefschetz homomorphism.

A. V. Jayanthan, J. K. Verma

Fiber cones of 0-dimensional ideals with almost minimal multiplicity in Cohen-Macaulay local rings are studied. Ratliff-Rush closure of filtration of ideals with respect to another ideal is introduced. This is used to find a bound on the reduction number with respect to an ideal. Rossi&#39;s bound on reduction number in terms of Hilbert coefficients is obtai

A. Felikson

Coxeter decompositions of hyperbolic simplices where studied in math.MG/0212010 and math.MG/0210067. In this paper we use the methods of these works to classify Coxeter decompositions of bounded convex pyramids and triangular prisms in the hyperbolic space H^3.

Piero D&#39;Ancona, Vladimir Georgiev

We investigate the continuity properties of the solution operator to the wave map system from the flat Minkowski space to a general nonflat target of arbitrary dimension, and we prove by an explicit class of counterexamples that this map is not uniformly continuous in the critical norms on any neighbourhood of zero.

Michael J. Larsen

A compact Lie group G and a faithful complex representation V determine a Sato-Tate measure, defined as the direct image of Haar measure on G with respect to the character of V. We give a necessary and sufficient condition for a Sato-Tate measure to be an isolated point in the set of such measures, regarded as a subset of the space of distributions. In parti

C. Adam

The lowest (``vector&#39;&#39;) and next-lowest (``scalar&#39;&#39;) bound-state masses of the massive Schwinger model have been determined recently to a very high accuracy numerically on the lattice. Therefore, improved results for these bound-state masses from analytical calculations are of some interest. Here, we provide such improved results by employing

Julieta Medina, Denjoe O&#39;Connor

Scalar fields are studied on fuzzy $S^4$ and a solution is found for the elimination of the unwanted degrees of freedom that occur in the model. The resulting theory can be interpreted as a Kaluza-Klein reduction of CP^3 to S^4 in the fuzzy context.

S. E. Derkachov, G. P. Korchemsky, A. N. Manashov

The exact solution of the noncompact SL(2,C) Heisenberg spin magnet reveals a hidden symmetry of the energy spectrum. To understand its origin, we solve the spectral problem for the model within quasiclassical approach. In this approach, the integrals of motion satisfy the Bohr-Sommerfeld quantization conditions imposed on the orbits of classical motion. In

W. J. Huo, T. F. Feng, Y. C. Xing

In this paper we firstly study various model-independent bounds on lepton flavor violation (LFV) in processes of $J/Ψ$, $Ψ&#39;$ and $Υ$ two-body decays, then calculate their branch ratios % By using the constraints from other ways, we obtain %the indirect bounds of ${\rm Br} (J/Ψ,Ψ&#39;,Υ\to ll&#39;)$ in models of the leptoquark, $R$ violating MSSM and topc

Kh. M. Beshtoev

It is noted that the theory of neutrino oscillations can be constructed only in the framework of the particle physics theory, where is a mass shell conception and then transitions (oscillations) between neutrinos with equal masses are real and between neutrinos with different masses are virtual. It is necessary to solve the question: which type of neutrino t

A. Andonov, S. Jadach, G. Nanava, Z. Was

Using the SANC system we study the one-loop electroweak standard model prediction, including virtual and real photon emissions, for the decays of on-shell vector and scalar bosons B --> f anti-f (gamma), where B is a vector boson, Z or W, or a Standard Model Higgs. The complete one-loop corrections and exact photon emission matrix element are taken into acco

R. Jeffrey Wilkes

This paper summarizes recent (as of SSI-02, in some cases updated in November, 2002) results from the Super-Kamiokande and K2K experiments. The interpretation of Super-Kamiokande results on atmospheric and solar neutrinos provides strong evidence for neutrino oscillations, hence non-zero neutrino mass. While statistics are still limited, K2K data are consist

K. A. Bronnikov, S. B. Fadeev, A. V. Michtchenko

Global properties of static, spherically symmetric configurations of scalar fields of sigma-model type with arbitrary potentials are studied in $D$ dimensions, including space-times containing multiple internal factor spaces. The latter are assumed to be Einstein spaces, not necessarily Ricci-flat, and the potential $V$ includes contributions from their curv

C. Lhuillier, P. Sindzingre

The properties of the groundstate and first excitations of 2dimensionnal quantum antiferromagnets are rapidly sketched. A special emphasis is put on the gapped phases: Valence Bond Crystals and the two types of Spin Liquids. New results on the spin susceptibility of small samples of the Heisenberg antiferromagnet on a kagomé lattice are displayed for compari

Uros Seljak, Rachel Mandelbaum, Patrick McDonald

Statistical properties of gas absorption in high redshift quasars such as power spectrum and bispectrum allow one to determine the evolution of structure over the redshift range 2<z<4. Sloan Digital Sky Survey (SDSS) will measure around 10,000 quasar spectra in this redshift range and will allow one to determine the growth factor with a few percent accuracy.