August 2004 arXiv papers — page 10

T. Banks

I introduce a new low energy effective description of Cosmological SUSY breaking. It requires the existence of a strongly interacting gauge theory at a scale of order $10^3$ GeV, some of whose fields carry standard model quantum numbers. SUSY breaking is communicated to the standard model through gaugino masses and the Higgs multiplets. The model also provid

Edmond L. Berger

The weak boson fusion process for neutral Higgs boson production is investigated with particular attention to the accuracy with which the Higgs boson couplings to weak bosons can be determined in final states that contain a Higgs boson plus at least two jets at CERN Large Hadron Collider energies. We determine that an accuracy of δg/g ~ 10% on the effective

A. Del Fabbro, D. Janc, M. Rosina, D. Treleani

The feasibility of tetraquark detection is studied. For the cc\bar{u}\bar{d} tetraquark we show that in present (SELEX, Tevatron, RHIC) and future facilities (LHCb, ALICE) the production rate is promising and we propose some detectable decay channels.

Harmen J. Warringa

We discuss the thermodynamics of the O(N) nonlinear sigma model in 1+1 dimensions. In particular we investigate the NLO 1/N correction to the 1PI finite temperature effective potential expressed in terms of an auxiliary field. The effective potential contains temperature-dependent divergences which cannot be renormalized properly. We argue that this problem

Kingman Cheung

We summarize a study on the production, decay, and detection of the strange-beauty squark as light as 200 GeV at hadronic and $e^+ e^-$ colliders. It was motivated by nearly maximal mixing between strange and beauty squarks.

K. Golec-Biernat

Recently Munier and Peschanski presented an analysis of the Balitsky--Kovchegov (BK) equation concerning the extraction of the saturation scale, using a simpler equation. We numerically analyze the full BK equation confirming the universality of their analysis.

G. E. Brown, C. -H. Lee, M. Rho

Given Brown/Rho scaling we thought of the mesons which are observed in Nambu-Jona Lasinio theory as collective modes. The pi, sigma, rho and A_1, should go smoothly through T_c as the temperature rose, going massless as T comes to T_c.

Igor R. Klebanov, Peter Ouyang

We reconsider the relationship between the bound state and the SU(3) rigid rotator approaches to strangeness in chiral soliton models. For non-exotic $S=-1$ baryons the bound state approach matches for small $m_K$ onto the rigid rotator approach, and the bound state mode turns into the rotator zero-mode. However, for small $m_K$, there are no $S=+1$ kaon bou

K. Hasegawa, C. S. Lim, Nobuhito Maru

We discuss a possibility to solve the gauge hierarchy problem in the framework of Gravity-Gauge-Higgs Unification scenario. We have calculated 1-loop correction to the mass of the scalar field, which is originated from 55-component of the metric, in five dimensional gravity theory with the bulk scalar field compactified on S^1. It is shown that the quadratic

A. D. Dolgov, L. B. Okun, M. V. Rotaev, M. G. Schepkin

We analyze a thought neutrino oscillation experiment in which neutrinos are produced by electrons colliding with atomic nuclei of a target. The neutrinos are detected by observing charged leptons, which are produced by neutrinos colliding with nuclei of the detector. We consider the case when both the target and detector nuclei have finite masses. (The case

Ping Hui, Xi-Yan Fang, Ting-yun Shi

Using the coupled cluster expansion with the random phase approximation, we calculate the long wavelength vacuum wave function and the vacuum energy of 2+1 dimensional Hamiltonian SU(2) lattice gauge theory (LGT) up to the seventh order. The coefficients $μ_0$, $μ_2$ of the vacuum wave function show good scaling behavior and convergence in high order calcula

H. E. Jackson

Measurements of single-spin asymmetries for semi-inclusive electro-production of pions and kaons in deep-inelastic scattering with transverse target polarization open a new window on the transverse quark and gluon structure of the nucleon. The first experimental results from such measurements as well as experiments in progress are discussed. Properties of th

J. Schieck, S. Kluth, S. Bethke, P. A. Movilla Fernandez

Data from e+e- annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV were used to study the four-jet rate as a function of the Durham algorithm's resolution parameter y_cut. The four-jet rate was compared to a QCD NLO order calculations including NLLA resummation of large logarithms. The strong co

L. Bartoszek

Mature technology of Liquid Argon Time Projection Chambers in conjunction with intense neutrino beams constructed at Fermilab offer a broad program of neutrino physics for the next decade.

K. Abe

We report measurements of radiative B decays with K eta gamma final states, using a data sample of 140 /fb recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- asymmetric energy collider. We observe B -> K eta gamma for the first time with a branching fraction of (6.9 +1.7-1.6 (stat) +1.3-1.0 (syst)) X 10^{-6} for M(Keta) < 2.4 GeV/

The Belle Collaboration

We present an improved measurement of the branching fraction for the electroweak penguin process B->Xsl+l-, where l is an electron or a muon and Xs is a hadronic system containing an s-quark. The measurement is based on a sample of 152 * 10^6 ~ Upsilon(4S) -> BB-bar events collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. The Xs

K. Abe

We have searched for decays that violate both lepton and baryon number using data collected by the Belle detector at the KEKB asymmetric e^+e^- collider. No signals are found in tau^- -> \bar{p} gamma, tau^- -> \bar{p} pi^0, tau^- -> \bar{Lambda} pi^-, and tau^- -> Lambda pi^- and we set upper limits on the branching fractions of B(tau^- -> \bar{p}gamma) < 3

K. Abe

We present a preliminary measurement of the inclusive charmless semileptonic branching fraction of the B meson, based on $140 fb^{-1}$ of data collected by the Belle detector at the KEKB $e^+e^-$ asymmetric collider. Events are tagged by fully reconstructing one of the B mesons, produced in pairs from $Υ(4S)$. The signal for $b \to u$ semileptonic decay is d

Carlo Rovelli, Daniele Colosi, Luisa Doplicher, Winston Fairbairn

We study how physical information can be extracted from a background independent quantum system. We use an extremely simple `minimalist&#39; system that models a finite region of 3d euclidean quantum spacetime with a single equilateral tetrahedron. We show that the physical information can be expressed as a boundary amplitude. We illustrate how the notions o

Marco Alberti, Marco Gavanelli, Evelina Lamma, Paola Mello

In classical CLP(FD) systems, domains of variables are completely known at the beginning of the constraint propagation process. However, in systems interacting with an external environment, acquiring the whole domains of variables before the beginning of constraint propagation may cause waste of computation time, or even obsolescence of the acquired data at

Ambedkar Dukkipati, M. Narasimha Murty, Shalabh Bhatnagar

Boltzmann selection is an important selection mechanism in evolutionary algorithms as it has theoretical properties which help in theoretical analysis. However, Boltzmann selection is not used in practice because a good annealing schedule for the `inverse temperature&#39; parameter is lacking. In this paper we propose a Cauchy annealing schedule for Boltzman

Stephan Heuscher, Stephan Jaermann, Peter Keller-Marxer, Frank Moehle

We discuss long-term preservation of and access to relational databases. The focus is on national archives and science data archives which have to ingest and integrate data from a broad spectrum of vendor-specific relational database management systems (RDBMS). Furthermore, we present our solution SIARD which analyzes and extracts data and data logic from al

G. Vignale

The Coulomb interaction between electrons of opposite spin orientations in a metal or in a doped semiconductor results in a negative off-diagonal component of the electrical resistivity matrix -- the so-called &#34;spin-drag resistivity&#34;. It is generally quite difficult to separate the spin-drag contribution from more conventional mechanisms of resistivi

F. L. Ning, T. Imai, B. W. Statt, F. C. Chou

We probed the local electronic properties of the mixed-valent Co(+4-x) triangular-lattice in Na{x}CoO{2}-yH{2}O by 59-Co NMR. We observed two distinct types of Co sites for x>=1/2, but the valence seems averaged out for x~1/3. Local spin fluctuations exhibit qualitatively the same trend down to ~100 K regardless of the carrier-concentration x, and hence the

Shuichi Wakimoto, Seunghun Lee, Peter M. Gehring, Robert J. Birgeneau

Soft phonons and diffuse scattering in insulating La$_{2-x}$Sr$_{x}$CuO$_4$ ($x=0.05$) have been studied by the neutron scattering technique. The X-point phonon softens from high temperature towards the structural transition temperature $T_{s}=410$ K, and the Z-point phonon softens again below 200 K. The Z-point phonon softening persists to low temperature,

Juan R. Sanchez

The Sznajd model is an Ising spin model representing a simple mechanism of making up decisions in a closed community. In the model each member of the community can take two attitudes A or B represented by a spin up or spin down state respectively. It has been shown that, in one-dimension starting from a totally random initial state, three final fixed points

Etienne Bustarret, Jozef Kacmarcik, Christophe Marcenat, Etienne Gheeraert

Homoepitaxial diamond layers doped with boron in the 10^20-10^21 /cm3 range are shown to be type II superconductors with sharp transitions (~0.2K) at temperatures increasing from 0 to 2.1 K with boron contents. The critical concentration for the onset of superconductivity is about 5-7 10^20 /cm3, close to the metal-insulator transition. The H-T phase diagram

Mattias Nilsson, Lars Rippe, Robert Klieber, Dieter Suter

A sequence of optical holeburning pulses is used to isolate transitions between hyperfine levels, which are initially buried within an inhomogeneously broadened absorption line. Using this technique selected transitions can be studied with no background absorption on other transitions. This makes it possible to directly study properties of the hyperfine tran

R. W. I. de Boer, N. N. Iosad, A. F. Stassen, T. M. Klapwijk

We investigate the effect of a small leakage current through the gate insulator on the stability of organic single-crystal field-effect transistors (FETs). We find that, irrespective of the specific organic molecule and dielectric used, leakage current flowing through the gate insulator results in an irreversible degradation of the single-crystal FET perform

P. Padhan, W. Prellier, B. Mercey

Magnetic multilayers of $(SrRuO_3)_m(SrMnO_3)_n$ were grown artificially using the pulsed laser deposition technique on (001)-oriented $SrTiO_3$ substrates. The state of strain at the interfaces and the structural coherency are studied in details utilizing asymmetrical $X$-ray diffraction and the $\sin ^2ψ$ method. First, the evolution of the lattice paramet

P. Padhan, W. Prellier, Ch. Simon, R. C. Budhani

Thin films of Pr0.5Ca0.5MnO3 manganites exhibiting charge/orbital-ordered properties with colossal magnetoresistance have been synthesized by the pulsed laser deposition technique on both (100)-SrTiO3 and (100)-LaAlO3 substrates. The effects of current-induced metallic-behavior of the films are investigated as a function of the temperature and the magnetic f

Augusto Gonzalez, Alain Delgado

Inelastic (Raman) light scattering intensities for a 42-electron quantum dot under off-resonance conditions and in different spin and angular momentum channels are computed in order to test whether final collective states become the dominant peaks in the process. The results of the calculations set a limit to the spread use of the off-resonant approximation

Satendra Pal Singh, Akhilesh Kumar Singh, Dhananjai Pandey

(1-x)Pb(Fe1/2Nb1/2)O3-PbTiO3(PFN-xPT)Ceramics with x = 0.13 sintered at 1473K show diffuse phase transition and very high dielectric constant at lower frequencies.The high value of dielectric constant at lower frequencies is shown to be due to the barrier layer formation.The resistivity of the PFN-xPT ceramics, obtained by complex impedance analysis, initial

B. Kaulakys, J. Ruseckas

Starting from the simple point process model of 1/f noise we derive a stochastic nonlinear differential equation for the signal exhibiting 1/f noise in any desirably wide range of frequency. A stochastic differential equation (the general Langevin equation with a multiplicative noise) that gives 1/f noise is derived for the first time. The solution of the eq

K. Sasaki, Y. Kawazoe

The basic properties of conducting electrons in carbon nanotubes are reviewed from a theoretical perspective, and studies performed on persistent currents in toroidal carbon nanotubes and on the local energy gap in deformed nanotubes are reported on.

Huai-Xiang Huang, You-Quan Li, Fu-Chun Zhang

We study charge ordered d-wave resonating valence bond states (dRVB) in the doped cuprates, and estimate the energies of these states in a generalized $t-J $ model by using a renormalized mean field theory. The long range Coulomb potential tends to modulate the charge density in favor of the charge ordered RVB state. The possible relevance to the recently ob

Kunal K. Das, G. S. Agarwal, Yu. M. Golubev, M. O. Scully

We use a Langevin approach to analyze the quantum noise in Coherent Anti-Stokes Raman Spectroscopy (CARS) in several experimental scenarios: with continuous wave input fields acting simultaneously and with fast sequential pulsed lasers where one field scatters off the coherence generated by other fields; and for interactions within a cavity and in free space

B. Lorenz, F. Yen, M. M. Gospodinov, C. W. Chu

The novel field-induced re-entrant phase in multiferroic hexagonal HoMnO3 is investigated to lower temperatures by dc magnetization, ac susceptibility, and specific heat measurements at various magnetic fields. Two new phases have been unambiguously identified below the Neel transition temperature, TN=76 K, for magnetic fields up to 50 kOe. The existence of

O. Tchernyshyov, R. Moessner, S. L. Sondhi

We investigate the Sp(N) mean-field theory for frustrated quantum magnets. First, we establish some general properties of its solutions; in particular, for small spin we propose simple rules for determining the saddle points of optimal energy. We then apply these insights to the pyrochlore lattice. For spins on a single tetrahedron, we demonstrate a continuo

Paul Fendley, Kareljan Schoutens, Hendrik van Eerten

We show that the hard-square lattice gas with activity z= -1 has a number of remarkable properties. We conjecture that all the eigenvalues of the transfer matrix are roots of unity. They fall into groups (``strings&#39;&#39;) evenly spaced around the unit circle, which have interesting number-theoretic properties. For example, the partition function on an M

C. N. R. Rao, F. L. Deepak

Following the theoretical predictions of ferromagnetism in Mn- and Co-doped ZnO, several workers reported ferromagnetism in thin films as well as in bulk samples of these materials. While some observe room-temperature ferromagnetism, others find magnetization at low temperatures. Some of the reports, however, cast considerable doubt on the magnetism of Mn- a

Uwe R. Fischer

Recent developments in simulating fundamental quantum field theoretical effects in the kinematical context of analogue gravity are reviewed. Specifically, it is argued that a curved space-time generalization of the Unruh-Davies effect -- the Gibbons-Hawking effect in the de Sitter space-time of inflationary cosmological models -- can be implemented and verif

Kazuo Hida

Ground state properties of the S=1/2 antiferromagnetic XXZ chain with Fibonacci exchange modulation are studied using the real space renormalization group method for strong modulation. The quantum dynamical critical behavior with a new universality class is predicted in the isotropic case. Combining our results with the weak coupling renormalization group re

S. Hill, S. Takahashi, R. S. Edwards, J. M. North

The variation with microwave frequency and temperature of previously reported anomalous peaks in the EPR spectra of Mn12-acetate, under large transverse fields, reveals that the molecular easy magnetization axes are tilted with respect to the global symmetry direction. More importantly, on the basis of the angle-dependence of fine structures observed in the

A. V. Dooglav, A. V. Egorov, I. R. Mukhamedshin, A. V. Savinkov

We present a detailed NQR, NMR and $μ$SR study of a magnetic phase obtained during a topotactic chemical reaction of YBa$_{2}$Cu$_{3}$O$_{6.5}$ high- temperature superconductor with low-pressure water vapor. Our studies give straightforward evidence that the &#39;&#39;empty&#39;&#39; Cu(1) chains play the role of an easy water insertion channel. It is shown

Daniel Babich, Matias Zaldarriaga

After the precise observations of the Cosmic Microwave Background (CMB) anisotropy power spectrum, attention is now being focused on the higher order statistics of the CMB anisotropies. Since linear evolution preserves the statistical properties of the initial conditions, observed non-Gaussianity of the CMB will mirror primordial non-Gaussianity. Single fiel

Casey Papovich, Eiichi Egami, Emeric Le Floc&#39;h, Pablo Perez-Gonzalez

New surveys with the Spitzer space telescope identify distant star-forming and active galaxies by their strong emission at far-infrared wavelengths, which provides strong constraints on these galaxies&#39; bolometric energy. Using early results from Spitzer surveys at 24 micron, we argue that the faint sources correspond to the existence of a population of i

D. Donato, R. M. Sambruna, M. Gliozzi

We present X-ray observations of the nuclear region of 25 Fanaroff-Riley I radio galaxies from the 3CRR and B2 catalogs, using data from the Chandra and XMM archives. We find the presence of a X-ray Central Compact Core (CCCX) in 13/25 sources, in 3/25 sources the detection of a CCCX is uncertain, while in the remaining 9/25 sources no CCCX is found. All the

Pedro F. Gonzalez-Diaz

This paper deals with a cosmological model in which the universe is filled with tachyon dark energy in order to describe current and future accelerating expansion. We obtain that the simplest condition for the regime of phantom energy to occur in this scenario is that the scalar field be Wick rotated to imaginary values which correspond to an axionic field c

J. Schmoll, G. N. Dodsworth, R. Content, J. R. Allington-Smith

The IMACS-IFU is an Integral Field Unit built for the IMACS spectrograph at the Magellan-I-Telescope at Las Campanas Observatory. It consists of two rectangular fields of 5 by 7 arcseconds, separated by roughly one arcminute. With a total number of 2000 spatial elements it is the second largest fiber-lenslet based IFU worldwide, working in a wavelength range

P. R. Ashcroft, C. van de Bruck, A. -C. Davis

We consider the evolution of cosmological perturbations during radion stabilization, which we assume to happen after a period of inflation in the early universe. Concentrating on the Randall-Sundrum brane world scenario, we find that if matter is present both on the positive and negative tension branes, the coupling of the radion to matter fields could have

Thomas Posch, Harald Mutschke, Anja C. Andersen

The origin of the so-called &#34;21 micron&#34; feature which is especially prominent in the spectra of some carbon-rich protoplanetary nebulae (PPNe}) is the matter of a lively debate. A large number of potential band carriers have been presented and discarded within the past decade. The present paper gives an overview of the problems related to the hithert

Helmut Wiesemeyer, Clemens Thum, Malcolm Walmsley

We present a survey of the polarization properties of mm-wavelength methanol masers, comprising both classes, and transitions from 84.5 to 157.0 GHz. Linear polarization is found in more than half of the observed objects, and circular polarization is tentatively detected in two sources. Class I and Class II CH_3OH masers show similar polarization properties.

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

The Burst and Transient Source Experiment (BATSE) aboard CGRO monitored the whole sky through 8 NaI(Tl) crystal scintillators sensitive in the 20 keV - 2 MeV energy band continuously from April 1991 until June 2000. Results are presented on the long term variabilty observed in the brightest Active Galactic Nuclei (AGN) present in the BATSE data archive. This

A. V. Thampan

We initiate numerical studies of differentially rotating magnetised (proto) neutron stars by studying - through construction from first principles - the coupling between an assumed differential rotation and an impressed magnetic field. For a perfect incompressible, homogeneous, non-dissipative fluid sphere immersed in an ambient plasma, we solve the (coupled

Michelle Doherty, Andrew Bunker, Robert Sharp, Gavin Dalton

We present preliminary results from a programme to obtain multi-object near-infrared spectroscopy of galaxies at redshifts $0.7<z<1.5$. We are using the instrument CIRPASS (the Cambridge Infra-Red PAnoramic Survey Spectrograph), in multi-object mode, to survey H-alpha in galaxies at $z\sim1$. We aim to address the true star formation history of the universe

P. Tanga, S. J. Weidenschilling, P. Michel, D. C. Richardson

For a long time, gravitational instability in the disk of planetesimals has been suspected to be the main engine responsible for the beginning of dust growth, its advantage being that it provides for rapid growth. Its real importance in planetary formation is still debated, mainly because the potential presence of turbulence can prevent the settling of parti

Peter Coles

A standard theoretical paradigm for the formation of large-scale structure in the distribution of galaxies has now been established, based on the gravitational instability of cold dark matter in a background cosmology dominated by vacuum energy. Significant uncertainties remain in the modelling of complex astrophysical processes involved in galaxy formation,

P. Chris Fragile, Stephen D. Murray, Douglas N. C. Lin

We examine the efficiency with which supernova-enriched gas may be ejected from dwarf disk galaxies, using a methodology previously employed to study the self-enrichment efficiency of dwarf spheroidal systems. Unlike previous studies that focused on highly concentrated starbursts, in the current work we consider discrete supernova events spread throughout va

F. Frontera, L. Amati, J. J. M. in &#39;t Zand, D. Lazzati

We report on observation results of the prompt X- and gamma-ray emission from GRB011211. This event was detected with the Gamma-Ray Burst Monitor and one of the Wide Field Cameras aboard the BeppoSAX satellite. The optical counterpart to the GRB was soon identified and its redshift determined (z = 2.140), while with the XMM-Newton satellite, the X-ray afterg

C. Scarlata, M. Stiavelli, M. Hughes, D. Axon

We present surface photometry for the central regions of a sample of 48 spiral galaxies (mostly unbarred and barred of types Sbc or Sc) observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. Surface brightness profiles were derived and modeled with a Nuker law. We also analyzed archival Wide Field Planetary Camera~2 image

J. H. Knapen, S. Stedman, D. M. Bramich, S. L. Folkes

We present optical observations of a sample of 57 spiral galaxies and describe the procedures followed to reduce the data. We have obtained images in the optical B and I broad bands, as well as in H alpha, with moderate spatial resolution and across wide enough fields to image the complete disks of the galaxies. In addition, we observed 55 of our sample gala

K. S. Dwarakanath, W. M. Goss, J. H. Zhao, C. C. Lang

We have imaged a region of about 5&#39; extent surrounding Sgr A* in the HI 21 cm-line absorption using the Very Large Array. A Gaussian decomposition of the optical depth spectra at positions within about 2&#39; (approx. 5 pc at 8.5 kpc) of Sgr A* detects a wide line underlying the many narrow absorption lines. The wide line has a mean peak optical depth of

N. Zwahlen, P. North, Y. Debernardi, L. Eyer

We present radial velocity and new interferometric measurements of the double star Atlas, which permit, with the addition of published interferometric data, to precisely derive the orbital parameters of the binary system and the masses of the components. The derived semi-major axis, compared with its measured angular size, allows to determine a distance to A

Takamichi Nakagami, Takahiko Matsubara, Jens Schmalzing, Yipeng Jing

We analyze the Minkowski functionals with a large $N$-body simulation of a standard $Λ$CDM model, focusing on transition scales between linear and non-linear gravitational evolution. We numerically calculate the Minkowski functionals with sufficient accuracies to investigate the transition scales, 10--$50\himpc$. The results are compared with analytic formul

Raquel Salmeron, Mark Wardle

We investigate the linear growth and vertical structure of the magnetorotational instability (MRI) in weakly ionised, stratified accretion discs. The magnetic field is initially vertical and dust grains are assumed to have settled towards the midplane, so charges are carried by electrons and ions only. Solutions are obtained at representative radial location

M. Sun, A. Vikhlinin, W. Forman, C. Jones

A new Chandra observation of the northwest region of the galaxy cluster A1367 reveals four cool galaxy coronae (0.4 - 1.0 keV) embedded in the hot intracluster medium (ICM) (5 - 6 keV). While the large coronae of NGC 3842 and NGC 3837 appear symmetric and relaxed, the galaxy coronae of the $\lsim$ L* galaxies (NGC 3841 and CGCG 97090) are disturbed and being

Fatma M. Reda, Duncan A. Forbes, Michael A. Beasley, Ewan J. O&#39;Sullivan

Isolated galaxies are important since they probe the lowest density regimes inhabited by galaxies. We define a sample of 36 nearby isolated early-type galaxies for further study. Our isolation criteria require them to have no comparable-mass neighbours within 2 B-band magnitudes, 0.67 Mpc in the plane of the sky and 700 km/s in recession velocity. New wide-f

Charlotte Froese Fischer, Robert H. Rubin

Energy levels, lifetimes, and transition probabilities for transitions between computed levels of 3d^5 of Fe IV are reported. The E2 and M1 transition probabilities are compared with earlier theoretical results, often only the values published by Garstang in 1958. From the available astronomical observations of optical emission lines arising from the same le

Masatoshi Imanishi, Keiichi Wada

We report on infrared K- (2-2.5 micron) and L-band (2.8-4.1 micron) slit spectroscopy of 23 Seyfert 1 galaxies in the CfA and 12 micron samples. A polycyclic aromatic hydrocarbon (PAH) emission feature at 3.3 micron in the L band is primarily used to investigate nuclear star-forming activity in these galaxies. The 3.3 micron PAH emission is detected in 10 so

L. J. Gou, P. Meszaros, T. R. Kallman

The rapid acquisition of positions by the upcoming Swift satellite will allow the monitoring for X-ray lines in GRB afterglows at much earlier epochs than was previously feasible. We calculate the possible significance levels of iron line detections as a function of source redshift and observing time after the trigger, for the Swift XRT, Chandra ACIS and XMM

Robert S. Maier

A machine-generated list of 192 local solutions of the Heun equation is given. They are analogous to Kummer&#39;s 24 solutions of the Gauss hypergeometric equation, since the two equations are canonical Fuchsian differential equations on the Riemann sphere with four and three singular points, respectively. Tabulation is facilitated by the identification of t

Abdou M. Abdel-Rehim, Randy Lewis

The pion form factor is calculated using quenched twisted mass QCD with beta=6.0 and maximal twisting angle omega=pi/2. Two pion masses and several values of momentum transfer are considered. The momentum averaging procedure of Frezzotti and Rossi is used to reduce lattice spacing errors, and numerical results are consistent with the expected O(a) improvemen

Philippe Brax, Carsten van de Bruck, Anne-Christine Davis, Justin Khoury

We show that the chameleon scalar field can drive the current phase of cosmic acceleration for a large class of scalar potentials that are also consistent with local tests of gravity. These provide explicit realizations of a quintessence model where the quintessence scalar field couples directly to baryons and dark matter with gravitational strength. We anal

John C. Collins, Andreas Metz

Universality in QCD factorization of parton densities, fragmentation functions, and soft factors is endangered by the process dependence of the directions of Wilson lines in their definitions. We find a choice of directions that is consistent with factorization and that gives universality between e^+e^- annihilation, semi-inclusive deep-inelastic scattering,

Andrew S. Friedman, Joshua S. Bloom

The use of GRB energetics for cosmography has long been advanced as a means to probe out to high redshifts, to the epoch of deceleration. However, the prompt energy release in GRBs, even when corrected for jetting geometry, is far from being a standard candle. We explore the cosmographic potential of a GRB standard candle based on the newly-discovered relati

Ian Affleck, Walter Hofstetter, David R. Nelson, Ulrich Schollwock

As a model of thermally excited flux liquids connected by a weak link, we study the effect of a single line defect on vortex filaments oriented parallel to the surface of a thin planar superconductor. This problem can be mapped onto the physics of a Luttinger liquid of interacting bosons in 1 spatial dimension with a point impurity. When the applied magnetic

Marcus Spradlin, Anastasia Volovich

We study weakly coupled SU(N) N = 4 super Yang-Mills theory on R x S^3 at infinite N, which has interesting thermodynamics, including a Hagedorn transition, even at zero Yang-Mills coupling. We calculate the exact one-loop partition function below the Hagedorn temperature. Our calculation employs the representation of the one-loop dilatation operator as a sp

Andrei Linde

If inflation can occur only at the energy density V much smaller than the Planck density, which is the case for many inflationary models based on string theory, then the probability of quantum creation of a closed or an infinitely large open inflationary universe is exponentially suppressed for all known choices of the wave function of the universe. Meanwhil

M. Lee, P. Oikonomou, P. Segalova, T. F. Rosenbaum

The rare earth hydride YH$_{3-δ}$ can be tuned through the metal-insulator transition both by changing $δ$ and by illumination with ultraviolet light. The transition is dominated by strong electron-electron interactions, with transport in the insulator sensitive to both a Coulomb gap and persistent quantum fluctuations. Via a systematic variation of UV illum

James Di Francesco, Philippe Andre, Philip C. Myers

We present combined BIMA interferometer and IRAM 30 m Telescope data of N2H+ 1-0 line emission across the nearby dense, star forming core Ophiuchus A (Oph A) at high linear resolution (e.g., ~1000 AU). Six maxima of integrated line intensity are detected which we designate Oph A-N1 through N6. The N4 and N5 maxima are coincident with the starless continuum o

Masao Mori, Masayuki Umemura, Andrea Ferrara

We consider a forming galaxy undergoing multitudinous supernova (SN) explosions, as a possible model of \lya blobs (LABs). For this purpose, an ultra--high resolution hydrodynamic simulation is performed using $1024^3$ grid points, where SN remnants are resolved with sufficient accuracy. It is found that multiple SN explosions produce kpc--size expanding hot

L. D. Carr, Charles W. Clark

The form and stability of quantum vortices in Bose-Einstein condensates with attractive atomic interactions is elucidated. They appear as ring bright solitons, and are a generalization of the Townes soliton to nonzero winding number $m$. An infinite sequence of radially excited stationary states appear for each value of $m$, which are characterized by concen

Y. Dagan, A. Biswas, M. C. Barr, W. M. Fisher

The temperature, doping and field dependences of the magnetoresistance (MR) in Pr_(2-x)Ce_(x)CuO_(4-delta) films are reported. We distinguish between orbital MR, found when the magnetic field is applied perpendicular to the ab planes, and the nearly isotropic spin MR. The latter, the major MR effect in the superconducting samples, appears in the region of th

Petter Brändén

The Neggers-Stanley conjecture (also known as the Poset conjecture) asserts that the polynomial counting the linear extensions of a partially ordered set on $\{1,2,...,p\}$ by their number of descents has real zeros only. We provide counterexamples to this conjecture.

Ulrich W. Heinz, Alex Sugarbaker

We propose a new procedure for constructing projected three-pion correlation functions which reduces undesirable artificial momentum dependences resulting from the commonly used procedure and facilitates comparison of three-pion correlation data with theoretical models.

Shin Muroya, Nobuo Sasaki

We calculate thermodynamic quantities and transport coefficients of a hadronic gas using a Monte Carlo hadronic collision event generator URASiMA. The obtained shear viscosity to entropy density ratio of the hadronic gas is approximately 0.3 -- 0.6 in the range $T$ = 100 -- 180MeV and is quite insensitive to the baryon number density.

Manfred Einsiedler, Mikhail Kapranov, Douglas Lind

We study the non-archimedean counterpart to the complex amoeba of an algebraic variety, and show that it coincides with a polyhedral set defined by Bieri and Groves using valuations. For hypersurfaces this set is also the tropical variety of the defining polynomial. Using non-archimedean analysis and a recent result of Conrad we prove that the amoeba of an i

Tobias Mühlenbruch

Matrix representations of Hecke operators on classical holomorphical cusp forms and the corresponding period polynomials are well known. In this article we derive representations of Hecke operators for vector valued period functions for the congruence subgroups $Γ_0(n)$. For this we use an integral transform from the space of vector valued cusp forms to the

Diederik Roest

We present a pedagogical discussion of the emergence of gauged supergravities from M-theory. First, a review of maximal supergravity and its global symmetries and supersymmetric solutions is given. Next, different procedures of dimensional reduction are explained: reductions over a torus, a group manifold and a coset manifold and reductions with a twist. Emp

J. T. Londergan

The NuTeV collaboration has made an independent determination of the Weinberg angle by measuring charged and neutral-current cross sections from neutrino and antineutrino DIS on iron. Their value differs by 3 standard deviations from that obtained from measurements at the Z pole. We review this experiment and assess various possible explanations for this res

Ralf Schützhold, William G. Unruh

It is demonstrated that the propagation of electro-magnetic waves in an appropriately designed wave-guide is (for large wave-lengths) analogous to that within a curved space-time -- such as around a black hole. As electro-magnetic radiation (e.g., micro-weaves) can be controlled, amplified, and detected (with present-day technology) much easier than sound, f

Andreas Ringwald, Yvonne Y. Y. Wong

We study the gravitational clustering of big bang relic neutrinos onto existing cold dark matter (CDM) and baryonic structures within the flat $Λ$CDM model, using both numerical simulations and a semi-analytical linear technique, with the aim of understanding the neutrinos&#39; clustering properties for direct detection purposes. In a comparative analysis, w

Simon Portegies Zwart, Jasinta Dewi, Tom Maccarone

We study the origin of the ultraluminous X-ray source M82-X1 in the nearby starburst galaxy M82. This X-ray source is of particular interest as it is currently the best candidate intermediate mass black hole; it is associated with a 54mHz quasi periodic oscillations with a relatively low (~1keV) black-body temperature. We perform detailed binary evolution ca

A. Ankay, E. Yazgan, S. Sahin, G. Karanfil

Two Galactic isolated strong X-ray pulsars seem to be in the densest environments compared to other types of Galactic pulsar. X-ray pulsar J1846-0258 can be in an early phase of anomalous X-ray pulsars and soft gamma repeaters if its average braking index is ~1.8-2.0. X-ray pulsar J1811-1925 must have a very large average braking index (n~11) if this pulsar

Michael Binger

The mass of the Higgs boson in the Split Supersymmetric Standard Model is calculated, including all one-loop threshold effects and the renormalization group evolution of the Higgs quartic coupling through two-loops. The two-loop corrections are very small (<<1 GeV), while the one-loop threshold corrections generally push the Higgs mass down several GeV.

Seiki Komiya, Han-Dong Chen, Shou-Cheng Zhang, Yoichi Ando

We report hole-doping dependence of the in-plane resistivity ρ_{ab} in a cuprate superconductor La_{2-x}Sr_{x}CuO_{4}, carefully examined using a series of high-quality single crystals. Our detailed measurements find a tendency towards charge ordering at particular rational hole doping fractions of 1/16, 3/32, 1/8, and 3/16. This observation appears to sugge

Jan Brugues, Joan Rojo, Jorge G. Russo

We find a new family of exact solutions in membrane theory, representing toroidal membranes spinning in several planes. They have energy square proportional to the sum of the different angular momenta, generalizing Regge-type string solutions to membrane theory. By compactifying the eleven dimensional theory on a circle and on a torus, we identify a family o

Mohammad R. Garousi, G. R. Maktabdaran

We study the S-matrix elements of the gauge invariant operators corresponding to on-shell closed strings, in open string field theory. In particular, we calculate the tree level S-matrix element of two ${\it arbitrary}$ closed strings, and the S-matrix element of one closed string and two open strings. By mapping the world-sheet of these amplitudes to the up

The Belle Collaboration, K. Abe

We present a precise measurement of the standard model CP-violation parameter sin(2phi1), the direct CP violation parameter |lambda|, the lifetimes of charged and neutral B mesons and their ratio, and the B0-B0bar mixing parameter Delta m_d based on a sample of 152 x 10^6 BB-bar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymm