August 2004 arXiv papers — page 11

L. Carigi, M. Peimbert, C. Esteban, J. Garcia-Rojas

Eleven models of Galactic chemical evolution, differing in the carbon, nitrogen,and oxygen yields adopted, have been computed to reproduce the Galactic O/H values obtained from H II regions. All the models fit the oxygen gradient, but only two models fit also the carbon gradient, those based on carbon yields that increase with metallicity due to stellar wind

C. Esteban, J. Garcia-Rojas, M. Peimbert, A. Peimbert

We present results of deep echelle spectrophotometry of eight Galactic HII regions located at Galactocentric distances between 6.3 and 10.4 kpc. The data have been taken with the Very Large Telescope (VLT) Ultraviolet Echelle Spectrograph (UVES) in the 3100 to 10360 A range. We have derived C++ and O++ abundances from recombination lines for all the objects,

Marcus Ruser

We present a general formalism allowing for efficient numerical calculation of the production of massless scalar particles from vacuum in a one-dimensional dynamical cavity, i.e. the dynamical Casimir effect. By introducing a particular parametrization for the time evolution of the field modes inside the cavity we derive a coupled system of first-order linea

A. I. Molev

Analogs of the classical Sylvester theorem have been known for matrices with entries in noncommutative algebras including the quantized algebra of functions on GL(N) and the Yangian for gl(N). We prove a version of this theorem for the twisted Yangians Y(g(N)) associated with the orthogonal and symplectic Lie algebras g(N)=o(N) or sp(N). This gives rise to r

Norio Konno

Concerning a discrete-time quantum walk X^{(d)}_t with a symmetric distribution on the line, whose evolution is described by the Hadamard transformation, it was proved by the author that the following weak limit theorem holds: X^{(d)}_t /t \to dx / π(1-x^2) \sqrt{1 - 2 x^2} as t \to \infty. The present paper shows that a similar type of weak limit theorems i

V. A. Babalola

The use of the properties of actions on an algebra to enrich the study of the algebra is well-trodden and still fashionable. Here, the notion and study of endomorphic elements of (Banach) algebras are introduced. This study is initiated, in the hope that it will open up, further, the structure of (Banach) algebras in general, enrich the study of endomorphism

T. Gershon

We report measurements of time-dependent decay rates for $B^0 \to D^{*\mp} π^\pm$ decays and extraction of CP violation parameters related to $ϕ_3$. We use a partial reconstruction technique, whereby signal events are identified using information only from the primary pion and the charged pion from the decay of the $D^{*\mp}$. The analysis uses $140 {\rm fb}

S. U. Kataoka

We report a measurement of CP asymmetry parameters in the decay B0(B0bar) -> J/Psi pi0, which is governed by the b->c cbar d transition. The analysis is based on a 140/fb data sample accumulated at the Upsilon(4S) resonance by the belle detector at the KEKB asymmetric-energy e+e- collider. We fully reconstruct one neutral B meson in the J/Psi pi0 final state

Robin Blume-Kohout, Wojciech H. Zurek

As quantum information science approaches the goal of constructing quantum computers, understanding loss of information through decoherence becomes increasingly important. The information about a system that can be obtained from its environment can facilitate quantum control and error correction. Moreover, observers gain most of their information indirectly,

J. Sherson, B. Julsgaard, E. S. Polzik

One of the main ingredients in most quantum information protocols is a reliable source of two entangled systems. Such systems have been generated experimentally several years ago for light but has only in the past few years been demonstrated for atomic systems. None of these approaches however involve two atomic systems situated in separate environments. Thi

Stefan Filipp, Yuji Hasegawa, Rudolf Loidl, Helmut Rauch

We present a split-beam neutron interferometric experiment to test the non-cyclic geometric phase tied to the spatial evolution of the system: the subjacent two-dimensional Hilbert space is spanned by the two possible paths in the interferometer and the evolution of the state is controlled by phase shifters and absorbers. A related experiment was reported pr

Atsushi Horikoshi, Kenichi Kinugawa

We apply the effective potential analytic continuation (EPAC) method to one-dimensional asymmetric potential systems to obtain the real time quantum correlation functions at various temperatures. Comparing the EPAC results with the exact results, we find that for an asymmetric anharmonic oscillator the EPAC results are in very good agreement with the exact o

Miloslav Znojil, Hynek Bila, Vit Jakubsky

The relativistic Klein-Gordon system is studied as an illustration of Quantum Mechanics using non-Hermitian operators as observables. A version of the model is considered containing a generic coordinate- and energy-dependent phenomenological mass-term $m^2(E,x)$. We show how similar systems may be assigned a pair of the linear, energy-independent left- and r

Michel Boyer

In 1990, Mermin presented a n player game that is won with certainty using n spin-1/2 particles in a GHZ state whilst no classical strategy (or local theory) can win with probability higher than ${1/2} + \frac{1}{2^{\lceil n/2 \rceil}}$ (which is larger than 1/2). This article first introduces a class of arithmetic games containing Mermin's and gives a q

E. Gultepe, M. L. Kurnaz

The rules that specify how the information contained in DNA codes amino acids, is called "the genetic code". Using a simplified version of the Penna nodel, we are using computer simulations to investigate the importance of the genetic code and the number of amino acids in Nature on population dynamics. We find that the genetic code is not a random pa

Enrique T. Munoz, Michael W. Deem

Until now, design of the annual influenza vaccine has relied on phylogenetic or whole-sequence comparisons of the viral coat proteins hemagglutinin and neuraminidase, with vaccine effectiveness assumed to correlate monotonically to the vaccine-influenza sequence difference. We use a theory from statistical mechanics to quantify the non-monotonic immune respo

Yi-Fan Chen, Peer Fischer, Frank W. Wise

The sign of the refractive index of any medium is soley determined by the requirement that the propagation of an electromagnetic wave obeys Einstein causality. Our analysis shows that this requirement predicts that the real part of the refractive index may be negative in an isotropic medium even if the electric permittivity and the magnetic permeability are

S. Soltan, J. Albrecht, H. --U. Habermeier

We report detailed studies on ferromagnet--superconductor bilayer structures. Epitaxial bilayer structures of half metal--colossal magnetoresistive La$_{\mathrm{2/3}}$Ca$_{\mathrm{1/3}}$MnO$_{\mathrm{3}}$ (HM--CMR) and high--$T_{\mathrm{c}}$ superconducting YBa$_{\mathrm{2}}$Cu$_{\mathrm{3}}$O$_{\mathrm{7-δ}}$(HTSC) are grown on SrTiO$_3$ (100) single--cryst

Andre Gsponer

Lemaitre was apparently the first to make an explicit coordinate transformation resulting in the removal of the singularity at r = a = 2m in the Schwarzschild metric, while Lanczos was the first to express doubts on the physical reality of that singularity since it could be introduced or removed by a transformation of coordinates.

J. Eggers, M. A. Fontelos

We consider an axisymmetric, freely suspended fluid drop with surface tension, whose viscosity is so large that both inertia and forcing by an external fluid can be ignored. We show that whatever be the initial condition, pinchoff can never occur.

P. von Brentano, V. Werner, R. F. Casten, C. Scholl

It is shown that strong 0+2 -> 0+1 E0 transitions provide a clear signature of phase transitional behavior in finite nuclei. Calculations using the IBA show that these transition strengths exhibit a dramatic and robust increase in spherical-deformed shape transition regions, that this rise matches well the existing data, that the predictions of these E0 tran

B. Saghai

Very recent eta and K+ photoproduction data on the proton from threshold up to E = 2.6 GeV are interpreted within a chiral constituent quark formalism, which embodies all known nucleon and hyperon resonances. Possible contributions from an additional S11 resonance are presented.

N. A. Kudryashov

Link between the Painleve property and the first integrals of nonlinear ordinary differential equations in polynomial form is discussed. The form of the first integrals of the nonlinear differential equations is shown to determine by the values of the Fuchs indices. Taking this idea into consideration we present the algorithm to look for the first integrals

C. Dunn, P. Gilkey, S. Nikcevic

We exhibit a family of generalized plane wave manifolds of signature (2,2). The geodesics in these manifolds extend for infinite time (i.e. they are complete), they are spacelike and timelike Jordan Osserman, and they are spacelike and timelike Jordan Ivanov-Petrova. Some are irreducible symmetric spaces. Some are homogeneous spaces but not symmetric. Some a

Ashwin Vaidya, Bong-Jae Chung

Perhaps one of the most intriguing questions in philosophy concerns the true nature of external reality. In this paper, we discuss some of the theories that have been put forth regarding the nature of reality and of our perceived universe. We develop an abstract mathematical model, whereby, several theories that have been proposed so, ranging from modern phy

Jerome Levine

In a recent paper we defined a new filtration of the mapping class group--the "Lagrangian" filtration. We here determine the successive quotients of this filtration, up to finite index. As an application we show that, for any additive invariant of finite-type (e.g. the Casson invariant), and any level of the Lagrangian filtration, there is a homology

Wenxiang Sun, Todd Young

Consider a $C^1$ vector field together with an ergodic invariant probability that has $\ell$ nonzero Lyapunov exponents. Using orthonormal moving frames along certain transitive orbits we construct a linear system of $\ell$ differential equations which is a reduced form of Liao's "standard system". We show that the Lyapunov exponents of this line

Philip J. Higgins

The relationships between thin elements, commutative shells and connections in cubical omega-categories are explored by a method which does not involve the use of pasting theory or nerves of omega-categories (both of which were previously needed for this purpose; see previous work by Al-Agl/Brown/Steiner. It is shown that composites of commutative shells are

Bernardo Lafuerza--Guillen, Jose Antonio Rodriguez--Lallena, Carlo Sempi

Relying on Kolmogorov's classical characterization of normable Topological Vector spaces, we study the normability of those Probabilistic Normed Spaces that are also Topological Vector spaces and provide a characterization of normable Šerstnev spaces. We also study the normability of other two classes of Probabilistic Normed Spaces.

Jan-Hendrik Evertse

Given a fixed number field K, we give non-trivial lower bounds for the distance between the conjugates of any number a from K in terms of the Mahler measure M(a) of a. In the case that K is a cubic field, our bound is best possible in terms of M(a). Our proof is based on Roth's theorem.

Jeb F. Willenbring, Gregg Zuckerman

The main goal of this paper is to prove the following theorem: Let $\frak k$ be an $\frak {sl}_2$-subalgebra of a semisimple Lie algebra $\frak g$, none of whose simple factors is of type $A1$. Then there exists a positive integer $b(\frak k, \frak g)$, such that for every irreducible finite dimensional $\frak g$-module $V$, there exists an injection of $\fr

Alicia Dickenstein, Laura Matusevich, Timur Sadykov

We undertake the study of bivariate Horn systems for generic parameters. We prove that these hypergeometric systems are holonomic, and we provide an explicit formula for their holonomic rank as well as bases of their spaces of complex holomorphic solutions. We also obtain analogous results for the generalized hypergeometric systems arising from lattices of a

Robert S. Maier

The reductions of the Heun equation to the hypergeometric equation by polynomial transformations of its independent variable are enumerated and classified. Heun-to-hypergeometric reductions are similar to classical hypergeometric identities, but the conditions for the existence of a reduction involve features of the Heun equation that the hypergeometric equa

Peter van Nieuwenhuizen

We give an introduction to rigid supersymmetry, supergravity and superspace by considering a quantum mechanical model. We analyze the constraints in superspace in this simplified model, and compare the Hamiltonian and Lagrangian BRST formalism.

P. S. Howe

Higher-order invariants and their role as possible counterterms for supergravity theories are reviewed. It is argued that N=8 supergravity will diverge at 5 loops. The construction of $R^4$ superinvariants in string and M-theory is discussed.

Richard Shurtleff

A `covariant' field that transforms like a relativistic field operator is required to be a linear combination of `canonical' fields that transform like annihilation and creation operators and with invariant coefficients. The Invariant Coefficient Hypothesis contends that this familiar construction by itself yields useful results. Thus, just the trans

S. Bellucci, P. Y. Casteill, J. F. Morales, C. Sochichiu

We review the spin bit model describing anomalous dimensions of the operators of Super Yang--Mills theory. We concentrate here on the scalar sector. In the limit of large $N$ this model coincides with integrable spin chain while at finite N it has nontrivial chain splitting and joining interaction.

JoAnne L. Hewett, Ben Lillie, Manuel Masip, Thomas G. Rizzo

We examine the experimental signatures for the production of gluinos at colliders and in cosmic rays within the split supersymmetry scenario. Unlike in the MSSM, the gluinos in this model are relatively long-lived due to the large value of the squark masses which mediate their decay. Searches at colliders are found to be sensitive to the nature of gluino fra

T. Hahn

Two methods to reduce the CPU time needed for the numerical evaluation of cross-sections and similar quantities are discussed.

Andre de Gouvea

The fact that neutrinos have mass allows them to possess many other properties, like a magnetic dipole moment and a finite decay width. Theoretical expectations for these are, however, well beyond current experimental bounds, and the discovery of new exotic neutrino properties would indicate the presence of (more) new physics. Here, I review some of the curr

T. Gleisberg, S. Hoeche, F. Krauss, A. Schaelicke

Some results highlighting the status of a new version of a cluster fragmentation model for the Monte Carlo event generator Sherpa are presented. In its present version this model is capable of simulating e+e- annihilation events into light-quark and gluon jets. We compare results for different multiplicity and momentum distributions to available SLD and LEP

A. Vogt

The Fortran package QCD-PEGASUS is presented. This program provides fast, flexible and accurate solutions of the evolution equations for unpolarized and polarized parton distributions of hadrons in perturbative QCD. The evolution is performed using the symbolic moment-space solutions on a one-fits-all Mellin inversion contour. User options include the order

David E. Miller

We discuss the quantum state structure on the basis of $SU(3)_c$ for some known exotic quark systems using a model which describes these particular states as highly correlated diquarks and antidiquarks. We are then able to calculate for a single colored diquark a finite von Neumann entropy from the quantum reduced density matrix, from which we explicitly eva

J. R. Andersen, V. Del Duca, S. Frixione, F. Maltoni

We investigate heavy-quark production as a function of the rapidity interval between two heavy quarks in hadronic collisions. We compare the results relevant to bottom production at the Tevatron and at LHC, obtained using exact leading-order and NLO pQCD production, as well as the contribution of the 4b channel with and without the addition of BFKL gluon rad

S. M. Barr, Bumseok Kyae

The possibility is examined that the masses of the light quarks $u$ and $d$ have varied over the course of the universe's evolution. Such a variation would have an effect on axion cosmology, and can be the basis of a solution of the so-called axion energy problem. If this is the case, a scalar force somewhat weaker than gravity could exist that has a ran

The L3 Collaboration

The absolute muon flux between 20 GeV and 3000 GeV is measured with the L3 magnetic muon spectrometer for zenith angles ranging from 0 degree to 58 degree. Due to the large exposure of about 150 m2 sr d, and the excellent momentum resolution of the L3 muon chambers, a precision of 2.3 % at 150 GeV in the vertical direction is achieved. The ratio of positive

B. Aubert, BABAR collaboration

We report on the inclusive branching fractions of $B^-$ and of ${\bar B}^0$ mesons decaying to ${D^0 X}$, ${{\bar D}^0 X}$, ${D^+ X}$, ${D^- X}$, ${D_s^+ X}$, ${D_s^- X}$, ${Λ_c^+ X}$, ${{\bar Λ}_c^- X}$, based on a sample of 88.9 million $B \bar B$ events recorded with the $BABAR$ detector at the $Υ(4S)$ resonance. Events are selected by completely reconstr

K. Abe

A search for mixing in the neutral D meson system was performed using semileptonic D^0 -> K- e+ nu decays. The flavor of neutral D mesons at production was tagged by the charge of the slow pion from the decay D*+ -> D^0 π+. The measurement was performed using 140 fb^-1 of data recorded by the Belle detector. The yield of right and wrong sign decays arising f

U. Husemann

The HERA-B collaboration has studied the production of charmonium and open charm states in collisions of 920 GeV protons with wire targets of different materials. The acceptance of the HERA-B spectrometer covers negative values of xF up to xF=-0.3 and a broad range in transverse momentum from 0.0 to 4.8 GeV/c. The studies presented in this paper include J/ps

K. Abe

We report the first observation of $B^0 \to D_s^+ π^-$ and an improved measurement of ${\bar B^0} \to D_s^+K^-$ based on $274 \times 10^6$ $B{\bar B}$ events collected with the Belle detector at KEKB. We measure the branching fractions ${\cal B}({\bar B^0} \to D_s^+K^-) = (2.93 \pm 0.55 \pm 0.79) \times 10^{-5}$ and ${\cal B}(B^0 \to D_s^+ π^-) = (1.94 \pm 0

K. Abe

We report on an improved study of $\bar{B}^0 \to D^{(*)0} \bar{K}^{(*)0}$ decays, based on $274 \times 10^6$ $B{\bar B}$ events collected with the Belle detector at KEKB. The following branching fractions have been measured: ${\cal B}(\bar{B}^0 \to D^0 \bar{K}^0) = (3.72 \pm 0.65 \pm 0.37) \times 10^{-5}$ and ${\cal B}(\bar{B}^0 \to D^0 \bar{K}^{*0}) = (3.08

K. Abe

We report a measurement of the branching fractions in the B0->J/Psi pi+pi- decay based on a 140/fb data sample collected at the Upsilon(4S) energy with the Belle detector at the KEKB e+e- collider. Charged pion pairs are found to arise mainly from rho0 and f2 mesons; an upper limit for the non-resonant contribution is also set. The following branching fracti

Richard H. Price, Lior M. Burko

An L-pole perturbation in Schwarzschild spacetime generally falls off at late times t as t^{-2L-3}. It has recently been pointed out by Karkowski, Swierczynski and Malec, that for initial data that is of compact support, and is initially momentarily static, the late-time behavior is different, going as t^{-2L-4}. By considering the Laplace transforms of the

Santos B. Yuste

Weighted averaged finite difference methods for solving fractional diffusion equations are discussed and different formulae of the discretization of the Riemann-Liouville derivative are considered. The stability analysis of the different numerical schemes is carried out by means of a procedure close to the well-known von Neumann method of ordinary diffusion

Buddhapriya Chakrabarti, Chandan Dasgupta

We numerically study a one-dimensional conserved growth equation with competing linear (Ehrlich-Schwoebel) and nonlinear instabilities. As a control parameter is varied, this model exhibits a non-equilibrium phase transition between two mounded states, one of which exhibits slope selection and the other does not. The coarsening behavior of mounds in these tw

T. J. Stasevich, T. L. Einstein, R. K. P. Zia, M. Giesen

Within the solid-on-solid (SOS) approximation, we carry out a calculation of the orientational dependence of the step stiffness on a square lattice with nearest and next-nearest neighbor interactions. At low temperature our result reduces to a simple, transparent expression. The effect of the strongest trio (three-site, non pairwise) interaction can easily b

A. Kashuba

2D Fermi liquid driven by uniform alternating electric field at zero temperature may remain in quantum coherent non-equilibrium state. We develop a quasistatic approximation for strong and slow ac-fields and solve the problem of driven disordered 2D electron gas in high non-overlapping Landau levels. The broadening of Landau level has the Lorentz form and is

H. Choi, K. Yawata, T. M. Haard, J. P. Davis

The specific heat of superfluid $^{3}$He, disordered by a silica aerogel, is found to have a sharp discontinuity marking the thermodynamic transition to superfluidity at a temperature reduced from that of bulk $^{3}$He. The magnitude of the discontinuity is also suppressed. This disorder effect can be understood from the Ginzburg-Landau theory which takes in

J. A. Sauls, Yu. M. Bunkov, E. Collin, H. Godfrin

We report theoretical calculations of the normal-state spin diffusion coefficient of 3He in aerogel, including both elastic and inelastic scattering of 3He quasiparticles, and compare these results with experimental data for 3He in 98% porous silica aerogel. This analysis provides a determination of the elastic mean free path within the aerogel. Measurements

M. V. Sadovskii

We present a short review of our basic understanding of the physics of copper - oxide superconductors and formulate the list of "solved" and "unsolved" problems. The main problem remains theoretical description of the properties of the normal state, requiring clarification of the nature of the so called pseudogap state. We review simplified m

Hilmi Lus, Cevat Onur Aydin, Sinan Keten, Hakan Ismail Unsal

This article is concerned with the global behavior of agents in the El Farol bar problem. In particular, we discuss the global attendance in terms of its mean and variance, and show that there is a strong dependence of both on the externally imposed comfort level. We present a possible interpretation for the observed behavior, and propose that the mean atten

I. V. Bobkova, Yu. S. Barash

We find proximity-induced spontaneous spin and electric surface currents, at all temperatures below the superconducting T_c, in an isotropic s-wave superconductor deposited with a thin ferromagnetic metal layer with spin-orbit interaction. The currents are carried by Andreev surface states and generated as a joint effect of the spin-orbit interaction and the

B. H. Lavenda

Fundamental inconsistencies of superstatistics are highlighted. There is no such thing as a superposition of Boltzmann factors; what is actually derived is a generating function and not a normalizable probability density. The beta density of the second kind for the energy is shown to be subordinated to a $χ^2$-probability distribution, and this provides a po

I. Junier, E. Bertin

We study the dynamic phase diagram of a spin model associated with the Number Partitioning Problem, as a function of temperature and of the fraction $K/N$ of spins allowed to flip simultaneously. The case K=1 reproduces the activated behavior of Bouchaud's trap model, whereas the opposite limit $K=N$ can be mapped onto the entropic trap model proposed by

E. M. Epshtein, E. G. Fedorov, G. M. Shmelev

Dynamics is studied of an electron in a quasi-one-dimensional ballistic ring under circularly polarized electromagnetic field propagating along the normal to the ring plane. The average emission intensity from the ring is calculated. The value and direction of the electron average angular velocity in the ring depend on the incident wave parameters. It is fou

Shakeel Akbar, S. K. Hasanain, Nasia Azmat, M. Nadeem

Fe2O3 nanoparticles of different sizes ranging from 22 to 56nm were synthesized chemically by a modified sol-gel method. Pure alpha phase particles as well as particles with admixture of alpha and gamma phase were obtained and identified by x-ray and Mössbauer measurements. Different size and phase controlling parameters have been identified. The average siz

Hiroaki Onishi, Takashi Hotta

In order to clarify a key role of orbital degree of freedom in the spin S=1 Haldane system, we investigate ground-state properties of the t2g-orbital degenerate Hubbard model on the linear chain by using numerical techniques. Increasing the Hund's rule coupling in multi-orbital systems, in general, there occurs a transition from an antiferromagnetic to a

Roi Alonso, Timothy M. Brown, Guillermo Torres, David W. Latham

We report the detection of a transiting Jupiter-sized planet orbiting a relatively bright (V=11.79) K0V star. We detected the transit light-curve signature in the course of the TrES multi-site transiting planet survey, and confirmed the planetary nature of the companion via multicolor photometry and precise radial velocity measurements. We designate the plan

David W. Hogg, Christy A. Tremonti, Michael R. Blanton, Douglas P. Finkbeiner

The Spitzer Space Telescope First Look Survey Infrared Array Camera (IRAC) near and mid-infrared imaging data partially overlaps the Sloan Digital Sky Survey (SDSS), with 313 visually selected (r<17.6 mag) SDSS Main Sample galaxies in the overlap region. The 3.5 and 7.8 um properties of the galaxies are investigated in the context of their visual properties,

Damien Le Borgne, Brigitte Rocca-Volmerange, Philippe Prugniel, Ariane Lancon

We present PEGASE-HR, a new stellar population synthesis program generating high resolution spectra (R=10 000) over the optical range lambda=400--680 nm. It links the spectro-photometric model of galaxy evolution PEGASE.2 (Fioc & Rocca-Volmerange 1997) to an updated version of the ELODIE library of stellar spectra observed with the 193 cm telescope at the Ob

Gregory R. Sivakoff, Craig L. Sarazin, Jeffrey L. Carlin

(Abridged) We observed the X-ray bright E3 galaxy NGC 1600 and nearby group members with the Chandra X-ray Observatory ACIS S3. Unresolved emission dominates the observation; however, we resolved some emission into 71 sources, most of which are low-mass X-ray binaries (LMXBs) associated with NGC 1600. Twenty-one sources have L_X>2E39 ergs/s (0.3-10.0 keV; as

Tapas K. Das, Bozena Czerny

We employ a low angular momentum accretion-outflow scenario to model the flares emanating out from the central region of Sgr A$^*$. The primary donor for matter accreting onto the central SMBH of Sgr A$^*$ is assumed to be the WR star ISR 13 E3. We analytically calculate the specific energy and angular momentum density of stellar wind originating from ISR 13

G. Woan

The SKA&#39;s design is driven by the needs of cutting-edge radio astronomy for sensitivity and spacial resolution. However its design is also driven by the desire to explore the transient radio Universe. In addition to pulsars, the SKA will be able to carry out high time resolution observations of several classes of known and predicted transient sources. He

Lynne A. Valencic, Geoffrey C. Clayton, Karl D. Gordon

We have assembled a homogeneous database of 417 ultraviolet (UV) extinction curves for reddened sightlines having International Ultraviolet Explorer (IUE) spectra. We have combined these with optical and 2MASS photometry allowing estimates of the ratio of total-to-selective extinction, R(V), for the entire sample. Fitzpatrick-Massa (FM) parameters have also

Ilian T. Iliev, Paul R. Shapiro, Alejandro C. Raga

The weak, R-type ionization fronts (I-fronts) which swept across the intergalactic medium (IGM) during the reionization of the universe often found their paths blocked by cosmological minihaloes. When this happened, the neutral gas which filled each minihalo was photoevaporated; as the I-front burned its way through the halo, decelerating from R-type to D-ty

P. Filliatre, S. Chaty

The X-ray source IGR J16318-4848 was the first source discovered by INTEGRAL. The high energy spectrum exhibits such a high column density that the source is undetectable in X-rays below 2 keV. We used the NTT telescope of ESO to obtain optical and near-infrared (NIR) observations. We confirm the already proposed NIR counterpart and for the first time extend

A. B. Hill, E. J. Barlow, A. J. Bird, A. J. Dean

The BATSE mission aboard CGRO observed the whole sky for 9 years in the 20 keV - 2 MeV energy band. Flat-fielding of the temporal variations in the background present in the data set has been accomplished through a GEANT3 Monte-Carlo simulation - the BATSE Mass Model (BAMM). The Earth Occultation technique (EOT) is used together with a maximum-likelihood ima

R. Benton Metcalf

The gravitational lensing constraints on the small mass end of the LCDM mass function are discussed. Here a conservative approach is taken where only the most difficult to explain image flux anomalies in strong QSO lenses are emphasized. Numerical simulations are performed to compare predictions for the LCDM small scale mass function with the observed flux r

A. D. Mackey, G. F. Gilmore

(Abridged) We investigate the hypothesis that some fraction of the globular clusters presently observed in the Galactic halo formed in external dwarf galaxies, by means of a detailed comparison between Zinn&#39;s &#34;old halo&#34;, &#34;young halo&#34;, and &#34;bulge/disk&#34; sub-systems and the globular clusters in local dwarf galaxies. The Galactic sub-

J. N. Reeves, D. Porquet, T. J. Turner

We report on a short XMM-Newton observation of the radio-quiet Narrow Line Seyfert 1 PG 1402+261. The EPIC X-ray spectrum of PG 1402+261 shows a strong excess of counts between 6-9 keV in the rest frame. This feature can be modeled by an unusually strong (equivalent width 2 keV) and very broad (FWHM velocity of 110000 km/s) iron K-shell emission line. The li

Lara Sidoli, Arvind N. Parmar, Tim Oosterbroek

We present results of a 0.1-100 keV BeppoSAX observation of the dipping LMXRB EXO 0748-676 performed in 2000 November. During the observation the source exhibited X-ray eclipses, type I X-ray bursts and dipping activity over a wide range of orbital phases. The 0.1-100keV &#34;dip-free&#34;(ie. dipping and eclipsing intervals excluded) spectrum is complex,esp

G. Weidenspointner, M. J. Harris, S. Sturner, B. J. Teegarden

Intense and complex instrumental backgrounds, against which the much smaller signals from celestial sources have to be discerned, are a notorious problem for low and intermediate energy gamma-ray astronomy (~50 keV - 10 MeV). Therefore a detailed qualitative and quantitative understanding of instrumental line and continuum backgrounds is crucial for most sta

Duncan A. Forbes, Favio Raul Faifer, Juan Carlos Forte, Terry Bridges

We present Sloan g and i imaging from the GMOS instrument on the Gemini North telescope for the globular cluster (GC) system around the Virgo galaxy NGC 4649 (M60). Our three pointings, taken in good seeing conditions, cover an area of about 90 sq. arcmins. We detect 2,151 unresolved sources. Applying colour and magnitude selection criteria to this source li

Daniel Green, William G. Unruh

The use of techniques from loop quantum gravity for cosmological models may solve some difficult problems in quantum cosmology. The solutions under a number of circumstances have been well studied. We will analyse the behaviour of solutions in the closed model, focusing on the behaviour of a universe containing a massless scalar field. The asymptotic behavio

E. Akalin, M. U. Akhmet

In this paper, we define B-smooth discontinuous dynamical systems which can be used as models of various processes in mechanics, electronics, biology and medicine. We find sufficient conditions to guarantee the existence of such systems. These conditions are easy to verify. Appropriate examples are constructed.

Kazuo Hosomichi

We study N=2 Liouville theory with arbitrary central charge in the presence of boundaries. After reviewing the theory on the sphere and deriving some important structure constants, we investigate the boundary states of the theory from two approaches, one using the modular transformation property of annulus amplitudes and the other using the bootstrap of disc

L. Anguelova, P. A. Grassi, P. Vanhove

We generalize to the eleven-dimensional superparticle Berkovits&#39; prescription for loop computations in the pure spinor approach to covariant quantization of the superstring. Using these ten- and eleven-dimensional results, we compute covariantly the following one-loop amplitudes: C\wedge X_8 in M-theory; B\wedge X_8 in type II string theory and F^4 in ty

Claude Sabbah

We show that the Fourier-Laplace transform of an irreducible regular differential system on the Riemann sphere underlies, when one only considers the part at finite distance, a polarizable regular twistor $\mathcal{D}$-module. The associated holomorphic bundle out of the origin is therefore equipped with a natural harmonic metric with a tame behaviour near t

Y. Chao

We report the first observation of the decay B0->pi0pi0, using a 253/fb data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- collider. The measured branching fraction is BF(B0->pi0pi0) = {2.32 +0.4-0.5(stat) +0.2-0.3(syst)} x 10^-6, with a significance of 5.8 standard deviations including systematic uncertainties. We al

Nan Li, Bo-Qiang Ma

The neutrino mixing matrix is expanded in powers of a small parameter $λ$, which approximately equals to 0.1. The meaning of every order of the expansion is discussed respectively, and the range of $λ$ is carefully calculated. We also present some applications of this new parametrization, such as to the expression of the Jarlskog parameter $J$, in which the

Shin&#39;ichi Nojiri, Sergei D. Odintsov

As it follows from the classical analysis, the typical final state of the dark energy universe where dominant energy condition is violated is finite time, sudden future singularity (Big Rip). For a number of dark energy universes (including scalar phantom and effective phantom theories as well as specific quintessence model) we demonstrate that quantum effec

Daniel Green, William G. Unruh

The cause of the collapse of the Tacoma Narrows Bridge has been a topic of much debate and confusion since the day it fell. Many mischaracterizations of the observed phenomena have limited the widespread understanding of the problem. Nevertheless, there has always been an abundance of evidence in favour of a negative damping model. Negative damping, or posit

Reginald T. Cahill

The Gravity Probe B (GP-B) satellite experiment will measure the precession of on-board gyroscopes to extraordinary accuracy. Such precessions are predicted by General Relativity (GR), and one component of this precession is the `frame-dragging&#39; or Lense-Thirring effect, which is caused by the rotation of the earth, and the other is the geodetic effect.

Kyung Hyuk Kim, Hong Qian

We investigate the nonequilibrium steady-state thermodynamics of single Brownian macromolecules with inertia under feedback control in isothermal ambient fluid. With the control being represented by a velocity-dependent external force, we find such open systems can have a negative entropy production rate and we develop a mesoscopic theory consistent with the

Han-Ying Guo, Jianzhong Pan, Bin Zhou

Based on the Euler-Lagrange cohomology groups $H_{EL}^{(2k-1)}({\cal M}^{2n}) (1 \leqslant k\leqslant n)$ on symplectic manifold $({\cal M}^{2n}, ω)$, their properties and a kind of classification of vector fields on the manifold, we generalize Liouville&#39;s theorem in classical mechanics to two sequences, the symplectic(-like) and the Hamiltonian-(like) L

Kai-Uwe Bux, Kevin Wortman

We determine when an arithmetic subgroup of a reductive group defined over a global function field is of type FP_\infty by comparing its large-scale geometry to the large-scale geometry of lattices in real semisimple Lie groups.

N. Christopher Phillips

We give examples of minimal diffeomorphisms of compact connected manifolds which are not topologically orbit equivalent, but whose transformation group C*-algebras are isomorphic. The examples show that the following properties of a minimal diffeomorphism are not invariants of the transformation group C*-algebra: having topologically quasidiscrete spectrum;

Tetsuya Takahashi

Let $F$ be a non-Archimedean local field with finite residual field of characteristic $p$. In this article we calculate the $ε$-factor of pairs for $\GL_l(F) \times \GL_{l&#39;}(F)$ where $l$ and $l&#39;$ are distinct primes including the case $l=p$. For this calculation, we use the local Langlands correspondence and non-Galois base change lift. This method

Huaxin Lin, N. Christopher Phillips

Let X be an infinite compact metric space with finite covering dimension and let h be a minimal homeomorphism of X. Let A be the associated crossed product C*-algebra. We show that A has tracial rank zero whenever the image of K_0 (A) in the affine functions on the tracial state space of A is dense. As a consequence, we show that these crossed product C*-alg

Anatoliy V. Tushev

In the presented paper we consider some methods of studying of prime ideals in group algebras of abelian groups of finite rank