October 2001 arXiv papers — page 11

Charles W. Danforth, J. Christopher Howk, Alex W. Fullerton, William P. Blair

We present an atlas of 57 Large Magellanic Cloud (LMC) and 37 Small Magellanic Cloud (SMC) observations obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. The atlas highlights twelve interstellar absorption line transitions at a resolution of ~15 km/s. These transitions cover a broad range of temperatures, ionization states, and abund

R. M. Betta, G. Peres, F. Reale, S. Serio

We revisit a well-studied solar flare whose X-ray emission originating from a simple loop structure was observed by most of the instruments on board SMM on November 12 1980. The X-ray emission of this flare, as observed with the XRP, was successfully modeled previously. Here we include a detailed modeling of the transition region and we compare the hydrodyna

The Milagro Collaboration

The Milagro Gamma Ray Observatory, located at an altitude of 8,600 feet in the Jemez Mountains of New Mexico, is the world's first large-area water Cherenkov detector capable of continuously monitoring the entire sky for sources of TeV gamma rays. It is uniquely capable of searching for transient sources of VHE gamma rays. The core of the detector is a 6

Duane Gruber, Yoel Rephaeli

The cluster of galaxies A2319 was observed in 1999 for 160 ks by the PCA and HEXTE instruments aboard the RXTE satellite. No noticeable variability is seen in the emission measured by either instrument over the 8 week observation. Fitting the RXTE data by a single thermal component we obtain $kT = 8.6 \pm 0.1$ (90% confidence limits), a low iron abundance $Z

G. S. Tsarevsky, E. P. Pavlenko, R. A. Stathakis, N. S. Kardashev

A complete sample of bright ROSAT sources with hard XRB-like spectra in the Galactic Plane (|b| < 15 deg.) has been tentatively identified with radio sources in the GB6/PMN/NVSS surveys, and subsequently observed with the Australia Telescope Compact Array and the Very Large Array. Most of them are unresolved at the sub-arcsec scale and have flat or inverted

Yoel Rephaeli

Comptonization of the cosmic microwave background (CMB) radiation by hot gas in clusters of galaxies - the Sunyaev-Zeldovich (S-Z) effect - is of great astrophysical and cosmological significance. In recent years observations of the effect have improved tremendously; high signal-to-noise images of the effect (at low microwave frequencies) can now be obtained

R. Landi, L. Bassani

In this work we present the observation of the Mkn 463 field performed with the MECS instrument on-board BeppoSAX in the 1.8-10.5 keV band. The Mkn 463 field is an example of an extragalactic field crowded with absorbed X-ray sources: apart from the Seyfert 2 galaxy Mkn 463 and the well known QSO PG 1352+183 (the only object showing no absorption), two other

E. Lastennet, J. Fernandes, E. Oblak, D. Valls-Gabaud

Individual components of well-detached binary systems are assumed to be two single-like stars with a common origin, i.e. they share the same chemical composition and same age. Therefore, one expects to fit the observed parameters of both components with a single isochrone at the same metallicity. We show that serious problems appear for systems with accurate

E. Lastennet, F. Cuisinier, T. Lejeune

Double-lined spectroscopic binaries which are also eclipsing provide the most accurate stellar data, and are consequently of first importance to improve stellar evolution modelling. While the mass and radius of each component of detached eclipsing binaries (EBs) can be accurately known, their temperature Teff and chemical composition ([Fe/H]) are still uncer

E. Lastennet, S. Lorenz-Martins, F. Cuisinier, T. Lejeune

We discuss the possibilities of the BaSeL models in its lowest temperature boundary (Teff ~ 2500 K for cool giants) to provide the Teff of AGB stars. We present the first step of our work, by comparing our predictions for the AGB star R Fornacis with the results of Lorenz-Martins & Lefevre (1994) based on the dust spectral energy distribution.

E. Lastennet, T. Lejeune, F. Cuisinier

COROT and GAIA are two future major space missions directly connected to most of the stellar astrophysic questions, from stellar physics to evolution of galaxies. We describe a project for the preparation of these two missions by using the possibilities of the ``BaSeL&#39;&#39; models, a library of theoretical stellar energy distributions, to provide automat

Rosaria Tantalo

In this poster line strength indices for new Single Stellar Populations (SSP) based on the recent stellar models with chemical compositions enhanced in the alpha-elements (Salasnich et al. 2000) are presented. The SSP indices have been calculated taking into account different methods to correct the &#34;Standard-Worthey Indices&#34; for the real chemical com

R. P. Fender, D. Rayner, S. A. Trushkin, K. O&#39;Brien

We report high sensitivity dual-frequency observations of radio oscillations from GRS 1915+105 following the decay of a major flare event in 2000 July. The oscillations are clearly observed at both frequencies, and the time-resolved spectral index traces the events between optically thin and thick states. While previously anticipated from sparse observations

T. Morel, R. Doyon, N. St-Louis

In an effort to better calibrate the supernova rate of starburst galaxies as determined from near-IR [Fe II] features, we report on a [Fe II] 1.644 microns line-imaging survey of a sample of 42 optically-selected SNRs in M33. A wide range of [Fe II] luminosities are observed within our sample (from less than 6 to 695 L_sun). Our data suggest that the bright

G. Vladilo

An analytical expression is presented that allows dust depletions to be estimated in different types of interstellar environments, including Damped Ly alpha systems. The expression is a scaling law of a reference depletion pattern and takes into account the possibility that the dust chemical composition may vary as a function of the dust-to-metals ratio and

Tohru Nagao, Takashi Murayama, Yasuhiro Shioya, Yoshiaki Taniguchi

In order to examine the prediction that the broad-line radio galaxies (BLRGs) with double-peaked Balmer lines harbor an accretion disk characterized by an advection-dominated accretion flow (ADAF) in their nuclei, we investigate narrow emission-line flux ratios of the narrow-line regions which are photoionized by the nuclear continuum radiation. We compile d

Sharon Hollander

We give a homotopy theoretic characterization of stacks on a site $\cC$ as the {\it homotopy sheaves} of groupoids on $\cC$. We use this characterization to construct a model category in which stacks are the fibrant objects. We compare different definitions of stacks and show that they lead to Quillen equivalent model categories. In addition, we show that th

J. D. Barrow, H. B. Sandvik, J. Magueijo

In some cosmological theories with varying constants there are anthropic reasons why the expansion of the universe must not be too {\it close} to flatness or the cosmological constant too close to zero. Using exact theories which incorporate time-variations in $α$ and in $G$ we show how the presence of negative spatial curvature and a positive cosmological c

E. V. L. de Mello, M. T. D. Orlando, J. L. Gonzaléz, E. S. Caixeiro

We report simultaneous hydrostatic pressure studies on the critical temperature $T_c$ and on the pseudogap temperature $T^*$ performed through resistivity measurements on an optimally doped high-$T_c$ oxide $Hg_{0.82}Re_{0.18}Ba_2Ca_2Cu_3O_{8+δ}$. The resistivity is measured as function of the temperature for several different applied pressure below 1GPa. We

Nicolas Moeller

We show that the D25 sliver wavefunction, just as the D-instanton sliver, factorizes when expressed in terms of half-string coordinates. We also calculate analytically the star-product of two zero-momentum eigenstates of $\hat{x}$ using the vertex in the oscillator basis, thereby showing that the star-product in the matter sector can indeed be seen as multip

Tadashi Takayanagi, Tadaoki Uesugi

In this paper we discuss D-branes in the Melvin background and its supersymmetric generalizations. In particular we determine the D-brane spectra in these backgrounds by constructing their boundary states explicitly, where some of the D-branes are supersymmetric. The results sensitively depend on whether the value of magnetic flux in the Melvin background is

Behnam Farid

We present the explicit expressions for the (regularized) terms in the large-epsilon asymptotic series of in particular the self-energy operator pertaining to arbitrary systems of interacting spin-s fermions in d spatial dimensions and deduce a variety of exact results concerning the general properties of this operator. We give especial attention to systems

A. de la Macorra, C. Stephan-Otto

We study the cosmological evolution of scalar fields that arise from a phase transition at some energy scale $\Lm_c$. We focus on negative power potentials given by $V=c\Lm_c^{4+n}ϕ^{-n}$ and restrict the cosmological viable values of $\Lm_c$ and $n$. We make a complete analysis of $V$ and impose $SN1a$ conditions on the different cosmological parameters. Th

S. B. Casal, Horacio S. Wio, S. Mangioni

We analyze here a model for an adsorbate system composed of many layers by extending a theoretical approach used to describe pattern formation on a monolayer of adsorbates with lateral interactions. The approach shows, in addition to a first order phase transition in the first layer, a transition in the second layer together with evidence of a &#34;cascade&#

C. Csaki, J. Erlich, V. V. Khoze, E. Poppitz

We consider non-perturbative effects in theories with extra dimensions and the deconstructed versions of these theories. We establish the rules for instanton calculations in 5D theories on the circle, and use them for an explicit one-instanton calculation in a supersymmetric gauge theory. The results are then compared to the known exact Seiberg-Witten type s

S. N. Taraskin, D. A. Drabold, S. R. Elliott

Analytic results for the asymptotic decay of the electron density matrix in insulators have been obtained in all three dimensions ($D=1 - 3$) for a tight-binding model defined on a simple cubic lattice. The anisotropic decay length is shown to be dependent on the energy parameters of the model. The existence of the power-law prefactor, $+AFw-propto r^{-D/2}$

Rachel Bean, Alessandro Melchiorri

We combine complementary datasets from Cosmic Microwave Background (CMB) anisotropy measurements, high redshift supernovae (SN-Ia) observations and data from local cluster abundances and galaxy clustering (LSS) to constrain the dark energy equation of state parameterized by a constant pressure-to-density ratio $w_Q$. Under the assumption of flatness, we find

I. B. Samsonov

We consider the noncommutative hypermultiplet model within harmonic superspace approach. The 1-loop four-point contributions to the effective action of selfinteracting q-hypermultiplet are computed. This model has two coupling constants instead of a single one in commutative case. It is shown that both these coupling constants are generated by 1-loop quantum

Y. Saiga, M. Imada

The ground-state phase diagram is numerically studied for an electronic model consisting of the spin exchange term (J) and the correlated hopping term (t_3: the three-site term). This model has no single-particle hopping and the ratio of the two terms is controlled by a parameter α\equiv 4 t_3 / J. The case of α=1 corresponds to complete suppression of singl

A. P. Levanyuk, S. A. Minyukov, A. Cano

We show that there exists a universal mechanism of long-range soliton attraction in three-dimensional solids and, therefore, of discontinuity of any commensurate-incommensurate (C-IC) phase transition. This mechanism is due to the strain dependence of the soliton self-energy and specific features of the solid-state elasticity. The role of this mechanism is s

J. Robert Buchler, Zoltan Kollath

Near the edges of the instability strip the rate of stellar evolution is larger than the growth-rate of the pulsation amplitude, and the same holds whenever the star is engaged in pulsational mode switching. Stellar evolution therefore controls both the onset of pulsation at the edges of the instability strip and of mode switching inside it. Two types of swi

A. Kageyama, S. Kaneko, N. Shimoyama, M. Tanimoto

We have investigated the lepton flavor violation in the supersymmetric framework assuming the large mixing angle MSW solution with the quasi-degenerate and the inverse-hierarchical neutrino masses. In the case of the quasi-degenerate neutrinos, the predicted branching ratio BR$(μ\to e γ)$ strongly depends on $m_ν$ and $U_{e3}$. For $U_{e3}\simeq 0.05$ with $

Y. Verbin, S. Madsen, A. L. Larsen, M. Christensen

The static string-like solutions of the Abelian Higgs model coupled to dilaton gravity are analyzed and compared to the non-dilatonic case. Except for a special coupling between the Higgs Lagrangian and the dilaton, the solutions are flux tubes that generate a non-asymptotically flat geometry. Any point in parameter space corresponds to two branches of solut

Krzysztof Turzynski

Using the freedom in SO(10) GUT&#39;s one can generalize the existing models without changing the mass spectrum of fermions to obtain a significant suppression of proton decay resulting from the baryon number violating operators of dimension 5. In some limiting cases, their contributions can be made negligible compared to the dimension 6 operators resulting

Maarten Golterman, Elisabetta Pallante

We point out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. The way in which this affects the lattice determination of weak matrix elements can be understood in the framework of (partially) quenched chiral perturbation theory.

L. Motyka, A. D. Martin, M. G. Ryskin

We discuss the BFKL approach to processes with large momentum transferred through a rapidity gap. The Mueller and Tang scheme to the BFKL non-forward parton-parton elastic scattering amplitude at large $t$, is extended to include higher conformal spins. The new contributions are found to decrease with increasing energy, as follows from the gluon reggeisation

Andrea Gregori

We investigate the perturbative and non-perturbative correspondence of a class of four dimensional dual string constructions with N=4 and N=2 supersymmetry, obtained as Z_2 or Z_2 x Z_2 orbifolds of the type II, heterotic and type I string. In particular, we discuss the heterotic and type I dual of all the symmetric Z_2 x Z_2 orbifolds of the type II string,

J. Meyer, K. Schwenzer, H. -J. Pirner, A. Deandrea

We calculate renormalization group flow equations for the linear sigma-model in large N_c approximation. The flow equations decouple and can be solved analytically. The solution is equal to a self consistent solution of the NJL model in the same approximation, which shows that flow equations are a promising method to extend the calculation to higher order in

Y. Kiyo, Y. Sumino

We study an effect of the off-shellness of the quark and antiquark inside a heavy quarkonium system on IR renormalons contained in the perturbative computations of the quarkonium energy levels. We demonstrate that, when the off-shellness p_Q^2 -m_Q^2 \sim alpha_S^2 m_Q^2 is larger than m_Q Lambda_QCD, renormalons in the energy levels as calculated in perturb

Daniel G. Barci, Eduardo S. Fraga, Marcelo Gleiser, Rudnei O. Ramos

We study the nonequilibrium growth of a weakly interacting homogeneous Bose gas after a quench from a high-temperature state to a temperature below the Bose-Einstein critical condensation temperature. We quantitatively characterize the departure from thermal equilibrium and observe the presence of two equilibration time scales. The equilibration times are sh

Mark D. Gould, Yao-Zhong Zhang, Shao-You Zhao

The Gaudin models based on the face-type elliptic quantum groups and the $XYZ$ Gaudin models are studied. The Gaudin model Hamiltonians are constructed and are diagonalized by using the algebraic Bethe ansatz method. The corresponding face-type Knizhnik-Zamolodchikov equations and their solutions are given.

Hitoshi Ito

The commutation relations of the composite fields are studied in the 3, 2 and 1 space dimensions. It is shown that the field of an atom consisting of a nucleus and an electron fields satisfies, in the space-like asymptotic limit, the canonical commutation relations within the sub-Fock-space of the atom. The field-particle duality in the bound state is discus

Michitoshi Yoshida, Masafumi Yagi, Sadanori Okamura, Kentaro Aoki

We found a very large, 35 kpc, emission-line region around the Seyfert type 2 galaxy NGC 4388, using deep narrow-band imaging with the prime focus camera (Suprime-Cam) of the Subaru telescope. This region consists of many faint gas clouds or filaments, and extends northeastwards from the galaxy. The typical H-alpha luminosity L(H-alpha) of the clouds is 10^3

M. Markevitch, A. H. Gonzalez, L. David, A. Vikhlinin

The Chandra image of the merging, hot galaxy cluster 1E0657-56 reveals a bow shock propagating in front of a bullet-like gas cloud just exiting the disrupted cluster core. This is the first clear example of a shock front in a cluster. From the jumps in the gas density and temperature at the shock, the Mach number of the bullet-like cloud is 2-3. This corresp

Warwick P. Bowen, Roman Schnabel, Hans -A. Bachor, Ping Koy Lam

We report the first direct experimental characterization of continuous variable quantum Stokes parameters. We generate a continuous wave light beam with more than 3 dB of simultaneous squeezing in three of the four Stokes parameters. The polarization squeezed beam is produced by mixing two quadrature squeezed beams on a polarizing beam splitter. Depending on

V. B. Bezerra, G. L. Klimchitskaya, C. Romero

The impedance boundary condition is used to calculate the Casimir force in configurations of two parallel plates and a shpere (spherical lens) above a plate at both zero and nonzero temperature. The impedance approach allows one to find the Casimir force between the realistic test bodies regardless of the electromagnetic fluctuations inside the media. Althou

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

We analyze the loss of fidelity in continuous variable teleportation due to non-maximal entanglement. It is shown that the quantum state distortions correspond to the measurement back-action of a field amplitude measurement. Results for coherent states and for photon number states are presented.

Giampiero Esposito

A proof is given that an invertible and a unitary operator can be used to reproduce the effect of a q-deformed commutator of annihilation and creation operators. In other words, the original annihilation and creation operators are mapped into new operators, not conjugate to each other, whose standard commutator equals the identity plus a correction proportio

R. Ahlswede, A. Winter

In this paper we present a simple proof of the strong converse for identification via discrete memoryless quantum channels, based on a novel covering lemma. The new method is a generalization to quantum communication channels of Ahlswede&#39;s recently discovered appoach to classical channels. It involves a development of explicit large deviation estimates t

B. Vasilishin, V. Andreev, V. Gorchenko, A. Kirichenko

The magnetic field control subsystem of the Nuclotron - a superferric ion synchrotron - is described. The bending (BM), focusing (QF) and defocusing (QD) magnets are powered by three supplies. The BMs are driven by the supply of a 6.3 kA nominal current. The QFs and QDs are connected in series and powered by the 6 kA supply. An additional supply of 200 A for

J. F. Geurdes

In a recent paper, Harada and Sachs suggested that the Fitzgerald-Lorentz contraction does not refer to a physical contraction but can perhaps best be seen as a &#39;currency conversion&#39;. In the present paper, this view is inspected, and it is found, beyond the immediate frame of the interpretation, that the Fitzgerald-Lorentz contraction leads to a cont

Alex Roxin, Hermann Riecke

We study the stability of patterns arising in rotating convection in weakly anisotropic systems using a modified Swift-Hohenberg equation. The anisotropy, either an endogenous characteristic of the system or induced by external forcing, can stabilize periodic rolls in the Küppers-Lortz chaotic regime. For the particular case of rotating convection with time-

Lutz Brusch, Alessandro Torcini, Markus Baer

We analyze the Eckhaus instability of plane waves in the one-dimensional complex Ginzburg-Landau equation (CGLE) and describe the nonlinear effects arising in the Eckhaus unstable regime. Modulated amplitude waves (MAWs) are quasi-periodic solutions of the CGLE that emerge near the Eckhaus instability of plane waves and cease to exist due to saddle-node bifu

Anil Maybhate, R. E. Amritkar, D. R. Kulkarni

We estimate the initial conditions of a multivariable dynamical system from a scalar signal, using a modified Newton-Raphson method incorporating the time evolution. We can estimate initial conditions of periodic and chaotic systems and the required length of scalar signal is very small. We also find that the information flow from one variable to the other h

Lars Andersson

Let $V$ be a maximal globally hyperbolic flat $n+1$--dimensional space--time with compact Cauchy surface of hyperbolic type. We prove that $V$ is globally foliated by constant mean curvature hypersurfaces $M_τ$, with mean curvature $τ$ taking all values in $(-\infty, 0)$. For $n \geq 3$, define the rescaled volume of $M_τ$ by $\Ham = |τ|^n \Vol(M,g)$, where

Manuel Blickle

Let R be a regular, local and F-finite ring defined over a field of finite characteristic. Let I be an ideal of height c with normal quotient $A=R/I$. It is shown that the local cohomology module H^c_I(R) contains a unique simple D_R--submodule L(A,R). This should be viewed as a finite characteristic analog of the Kashiwara--Brylinski D_R--module in characte

Stefan Schroeer

In modern form, Hilbert&#39;s Theorem 90 tells us that R^1f_*(G_m)=0, where f is the canonical map between the etale site and the Zariski site of a scheme X. I construct examples showing that the corresponding statement for algebraic spaces does not hold. The first example is a nonseparated smooth 1-dimensional bug-eyed cover in Kollar&#39;s sense. The secon

Mikhail Kudryavtsev

The Riemann problem is studied in the case when the unknown function has nonisolated singularities, concentrated on the real axis. The problem is used for the factorization of functions, holomorphic outside of the unit circle and the real axis, in the form of the product of two functions which have singulariries on the given set of the real axis.

Igor Podlubny

A solution to the more than 300-years old problem of geometric and physical interpretation of fractional integration and differentiation (i.e., integration and differentiation of an arbitrary real order) is suggested for the Riemann-Liouville fractional integration and differentiation, the Caputo fractional differentiation, the Riesz potential, and the Felle

Julian Pfeifle

In 1988, Kalai extended a construction of Billera and Lee to produce many triangulated (d-1)-spheres. In fact, in view of upper bounds on the number of simplicial d-polytopes by Goodman and Pollack, he derived that for every dimension d>=5, most of these (d-1)-spheres are not polytopal. However, for d=4, this reasoning fails. We can now show that, as already

Juergen Jost, Yuan-Long Xin

We prove some Bernstein theorems for entire space-like submanifolds in pseudo-Euclidean spaces and, as a corollary, we obtain a new proof of the Calabi-Pogorelov theorem on global solutions of Monge-Ampere equations.

Alexandre V. Borovik

We discuss basic structural properties of finite black box groups. A special emphasis is made on the use of centralisers of involutions in probabilistic recognition of black box groups. In particular, we suggest an algorithm for finding the $p$-core of a black box group of odd characteristic. This special role of involutions suggest that the theory of black

Boris Kruglikov

Motivated by a paper of Bolsinov and Taimanov DG/9911193 we consider non-holonomic situation and exhibit examples of sub-Riemannian metrics with integrable geodesic flows and positive topological entropy. Moreover the Riemannian examples are obtained as &#34;holonomization&#34; of sub-Riemannian ones. A feature of non-holonomic situation is non-compactness o

M. Borisavljevic, K. Dosen, Z. Petric

This paper gives a self-contained and complete proof of the isomorphism of freely generated monoids extracted from Temperley-Lieb algebras with monoids made of Kauffman&#39;s diagrams.

David Beckman, Daniel Gottesman, Alexei Kitaev, John Preskill

We show that the nondemolition measurement of a spacelike Wilson loop operator W(C) is impossible in a relativistic non-Abelian gauge theory. In particular, if two spacelike-separated magnetic flux tubes both link with the loop C, then a nondemolition measurement of W(C) would cause electric charge to be transferred from one flux tube to the other, a violati

Oscar J. C. Dias, Jose&#39; P. S. Lemos

We obtain spacetimes generated by static and spinning magnetic string sources in Einstein Relativity with negative cosmological constant. Since the spacetime is asymptotically a cylindrical anti-de Sitter spacetime, we will be able to calculate the mass, momentum, and electric charge of the solutions. We find two families of solutions, one with longitudinal

R. P. Woodard

I present an exact solution for the Heisenberg picture, Dirac electron in the presence of an electric field which depends arbitrarily upon the light cone time parameter $x^+ = (t+x)/\sqrt{2}$. This is the largest class of background fields for which the mode functions have ever been obtained. The solution applies to electrons of any mass and in any spacetime

Parthasarathi Majumdar

An elementary introduction is given to the problem of black hole entropy as formulated by Bekenstein and Hawking, based on the so-called Laws of Black Hole Mechanics. Wheeler&#39;s `It from Bit&#39; picture is presented as an explanation of plausibility of the Bekenstein-Hawking Area Law. A variant of this picture that takes better account of the symmetries

Andrea Gregori

We discuss the existence of a non-perturbative gauge sector that can raise the rank of the gauge group of the N_4=2 heterotic string up to 48. These gauge bosons, that don&#39;t exist in six dimensions, co-exist with those originating from small instantons shrinking to zero size.

A. Pankov, A. Babich

The four-fermion contact-interaction searches in the process $e^+e^-\toμ^+μ^-$ at a future $e^+e^-$ Linear Collider with c.m. energy $\sqrt{s}=0.5$ TeV and with both beams longitudinally polarized are studied. We evaluate the corresponding model-independent constraints on the coupling constants, emphasizing the role of beam polarization, and make a compariso

Alexander A. Osipov, Marcos Sampaio, Brigitte Hiller

Based on a recently derived effective chiral meson Lagrangian from the extended SU(2)\otimes SU(2) Nambu -- Jona-Lasinio (ENJL) model, in the linear realization of chiral symmetry, we extract to leading order in the 1/N_c expansion all associated relevant three-point functions ρ\to ππ, σ\to ππ, a_1 \to ρπ, a_1 \to σπ, as well as the amplitude for ππscatterin

Michal Majewski

Mass sum rules for meson multiplets derived from exotic commutators may be written for complex masses. Then the real parts give the well known mass formulae (GM-O, Schwinger, Ideal) and the imaginary ones give the corresponding sum rules for total hadronic widths. The masses and widths of the meson nonets submit to a definite orders. It thus follows that tab

V. I. Demchik, V. V. Skalozub

The spontaneous generation of the magnetic and chromomagnetic fields at high temperature is investigated in the Standard Model. The consistent effective potential including the one-loop and the daisy diagrams of all boson and fermion fields is calculated. The mixing of the generated fields due to the quark loop diagram is studied in detail. It is found that

Robert Fleischer

After a brief look at the well-known standard approaches to determine the angle gamma of the unitarity triangle, we focus on two kinds of strategies, employing $B\toπK$ modes, and U-spin-related B decays. Interesting &#34;puzzles&#34;, which may already be indicated by the present B-factory data, are pointed out, and the importance of the extraction of hadro

Nobuhiro Maekawa

In this talk, we propose a GUT scenario in which doublet-triplet splitting is naturally realized in SO(10) unification using the Dimopoulos-Wilczek mechanism and the realistic mass matrices of quarks and leptons are obtained in a simple way. For the neutrino sector, bi-maximal neutrino mixing angles are realized. Moreover, the generic interaction is allowed,

C. D. McMullen, S. Nandi

It is possible for the SM fields to propagate into one or more large extra compact dimensions. Such fields have associated KK excitations that produce additional contributions to the SM processes. We calculate the effects that these KK excitations have on cross sections for $e^{+}e^{-}$ collider processes in a model in which the SM gauge bosons, and perhaps

Stephan Dürr

I readdress the issue whether the topological charge of the gauge background has an influence on a hadronic observable. To this end pion correlators in the Schwinger model with 2 dynamical flavours are determined on subensembles with a fixed topological charge. It turns out that the answer depends on a specific function of the sea-quark mass and the box volu

Attilio Cucchieri, Daniel Zwanziger

In Gribov&#39;s scenario in Coulomb gauge, confinement of color charge is due to a long-range instantaneous color-Coulomb potential V(R). This may be determined numerically from the instantaneous part of the gluon propagator D_{44, inst} = V(R) δ(t). Confinement of gluons is reflected in the vanishing at k = 0 of the equal-time three-dimensionally transverse

Attilio Cucchieri, Tereza Mendes, Daniel Zwanziger

We present a numerical study of the space-space and time-time components of the gluon propagator at equal time in the minimal Coulomb gauge, and of the gluon and ghost propagators in the minimal Landau gauge. This work allows a non-perturbative evaluation of the running coupling constant and a numerical check of Gribov&#39;s confinement scenarios for these t

W. Bardeen, A. Duncan, E. Eichten, H. Thacker

The scalar isovector meson propagator is studied in quenched QCD. For the lightest quark masses used, this propagator is dominated by a quenched chiral loop effect associated with the $η&#39;$-$π$ two-meson intermediate state. Both the time dependence and the pion mass dependence of the effect are well-described by quenched chiral perturbation theory.

Guofeng Liu

We calculate the low-lying eigenvalues and eigenvectors of the hermitian domain wall Dirac operator on various gauge backgrounds by Ritz minimization. The mass dependence of these eigenvalues is studied to extract the physical 4 dimensional $λ$, whose spectral density is related to $<\barψ ψ>$ through the Banks-Casher relation, and $δm$, which represents the

T. Blum, RBC Collaboration

We present results for the imaginary parts of the I=0 and 2 $K\toππ$ decay amplitudes, Im$A_{0,2}$, and the ratio of CP violation parameters, $ε^\prime/ε$. Our calculation is done in the quenched approximation at $a^{-1}\approx 2$ GeV, lattice size $16^3\times 32$, using domain wall fermions with $L_s=16$. We study the three flavor case (charm is not an acti

L. Giusti, C. Hoelbling, C. Rebbi

We present results of a quenched QCD simulation with overlap fermions on a lattice of volume V = 16^3X32 at beta=6.0, which corresponds approximatively to a lattice cutoff of 2 GeV and an extension of 1.4 fm. From the two-point correlation functions of bilinear operators we extract the pseudoscalar meson masses and the corresponding decay constants. From the

C. Gattringer, M. Göckeler, P. E. L. Rakow, A. Schäfer

We analyze the eigenvalues and eigenvectors of the staggered Dirac operator in quenched lattice QCD in the vicinity of the deconfinement phase transition using the Lüscher-Weisz gauge action. The spectral and localization properties of the low-lying eigenmodes show characteristic differences between the Z_3 sectors above the critical temperature T_c. These f

A. Abada, Ph. Boucaud, G. Herdoiza, J. P. Leroy

We determine the conditions required to study the pion light-cone wave function Phi_pi with a new method: a direct display of the partons constituting the pion. We present the preliminary results of a lattice computation of Phi_pi following this direction. An auxiliary scalar-quark is introduced. The spectroscopy of its bound states is studied. We observe so

M. Hasenbusch, K. Jansen

We propose a modification of the Hybrid-Monte-Carlo algorithm that allows for a larger step-size of the integration scheme at constant acceptance rate. The key ingredient is the splitting of the pseudo-fermion action into two parts. We test our proposal at the example of the two-dimensional lattice Schwinger model and four-dimensional lattice QCD with two de

JLQCD Collaboration, S. Aoki, R. Burkhalter, M. Fukugita

We explore sea quark effects in the light hadron mass spectrum in a simulation of two-flavor QCD using the nonperturbatively O(a)-improved Wilson fermion action. In order to identify finite-size effects, light meson masses are measured on 12^3x48, 16^3x48 and 20^3x48 lattices with a~0.1 fm. On the largest lattice, where the finite-size effect is negligible,

JLQCD Collaboration, N. Tsutsui, S. Aoki, R. Burkhalter

Using the lattice NRQCD action for heavy quark, we calculate the heavy quark expansion parameters $μ_π^2$ and $μ_G^2$ for heavy-light mesons and heavy-light-light baryons. The results are compared with the mass differences among heavy hadrons to test the validity of HQET relations on the lattice.

Sunao Sakai, Atsushi Nakamura, Takuya Saito

We have studied the link-integration method for the improved actions. With this method the $η$ parameter in the medium to strong coupling regions is obtained. Effects of the self-energy terms for the $η$ parameters are small in the regions of $β$ and $η$ studied. After these investigations, the anisotropic lattice is used for the calculation of transport coe

Daniel M. Kaplan

The BTeV trigger system will be very ambitious, reconstructing almost all tracks in real time at 15 million 2-TeV ${\bar p} p$ interactions per second. The goal is substantially-increased sensitivity to rare effects in heavy-quark physics over that of existing experiments. The evolution of our approach is briefly summarized.

B. L. Hu, E. Verdaguer

Whereas semiclassical gravity is based on the semiclassical Einstein equation with sources given by the expectation value of the stress-energy tensor of quantum fields, stochastic semiclassical gravity is based on the Einstein- Langevin equation, which has in addition sources due to the noise kernel. The noise kernel is the expectation value of the stress-en

Kashif Alvi, Yuk Tung Liu

An important issue in the dynamics of neutron star binaries is whether tidal interaction can cause the individual stars to collapse into black holes during inspiral. To understand this issue better, we study the dynamics of a cluster of collisionless particles orbiting a non-rotating black hole, which is part of a widely separated circular binary. The compan

Hakan Andreasson, Gerhard Rein, Alan D. Rendall

It is shown that a spacetime with collisionless matter evolving from data on a compact Cauchy surface with hyperbolic symmetry can be globally covered by compact hypersurfaces on which the mean curvature is constant and by compact hypersurfaces on which the area radius is constant. Results for the related cases of spherical and plane symmetry are reviewed an

Stanislav V. Babak, Kostas Glampedakis

We study the dynamical evolution of perturbations in the gravitational field of a collapsing fluid star. Specifically, we consider the initial value problem for a massless scalar field in a spacetime similar to the Oppenheimer-Snyder collapse model, and numerically evolve in time the relevant wave equation. Our main objective is to examine whether the phenom

Audrey N. Selian

The purpose of this paper is to examine the major factors surrouding and contributing to the creation (and success) of Europe&#39;s 2nd generation &#39;GSM&#39; cellular system, and compare and contrast it to key events and recent developments in 3rd generation &#39;IMT-2000&#39; systems. The objective is to ascertain whether lessons from the development of

Sara Cohen, Yaron Kanza, Yakov Kogan, Werner Nutt

EquiX is a search language for XML that combines the power of querying with the simplicity of searching. Requirements for such languages are discussed and it is shown that EquiX meets the necessary criteria. Both a graph-based abstract syntax and a formal concrete syntax are presented for EquiX queries. In addition, the semantics is defined and an evaluation

Robert Cannon

ENUM marks either the convergence or collision of the public telephone network with the Internet. ENUM is an innovation in the domain name system (DNS). It starts with numerical domain names that are used to query DNS name servers. The servers respond with address information found in DNS records. This can be telephone numbers, email addresses, fax numbers,

Ulrich Stumpf

The ability to make international roaming calls is of increasing importance to customers in Europe. This contrasts with various complaints that retail prices of roaming calls are rigid and excessive. The focus if the paper is on wholesale roaming, which is the prime determinant of retail roaming prices. The paper analyses the structural conditions of wholesa

Sam Chandan, Christiaan Hogendorn

This paper analyzes the pricing of transit traffic in wireless peer-to-peer networks using the concepts of direct and indirect network externalities. We first establish that without any pricing mechanism, congestion externalities overwhelm other network effects in a wireless data network. We show that peering technology will mitigate the congestion and allow

Susan Oberlander

Independent regulatory commissions such as the Federal Communications Commission (FCC) must produce policies that reflect technical expertise, legal precedent, and stakeholder input. Given these situational imperatives, how does the FCC implement independence in its decision-making? This research explicates some of the underlying rules, resources, and relati