October 2006 arXiv papers — page 46

S. V. Demidov, D. S. Gorbunov

We further discuss possible sgoldstino interpretation of the observation, reported by the HyperCP collaboration, of three Σ^+\to pμ^+μ^- decay events with dimuon invariant mass 214.3 MeV within detector resolution. With sgoldstino mass equal to 214.3 MeV, this interpretation can be verified at existing and future B- and ϕ-factories. We find that the most nat

P. A. Sturrock

We analyze Super-Kamiokande, SNO, and photospheric magnetic-field data for the common time interval, namely the SNO D2O phase. Concerning rotational modulation, the magnetic-field power spectrum shows the strongest peaks at the second and sixth harmonics of the solar synodic rotation frequency [3 nu(rot) and 7 nu(rot)]. The restricted Super-Kamiokande datase

E. Kh. Akhmedov

A brief overview of selected topics in the theory and phenomenology of neutrino oscillations is given. These include: oscillations in vacuum and in matter; phenomenology of 3-flavour neutrino oscillations and effective 2-flavour approximations; CP and T violation in neutrino oscillations in vacuum and in matter; matter effects on ν_μ\leftrightarrow ν_τoscill

T. N. Pham

The branching ratios and CP asymmetries of $B\to ππ$ decays measured in B factory experiments indicate a large ratio of color-suppressed ($C$) to color-allowed ($T$) tree contributions and a large relative phase between the tree and penguin amplitude. In this talk, I would like to report on a recent analysis to see whether the large $C/T$ ratio can be explai

C. Albertus, J. M. Flynn, E. Hernandez, J. Nieves

The semileptonic decay B->pi is studied starting from a simple quark model that takes into account the effect of the B* resonance. A novel, multiply subtracted, Omnes dispersion relation has been implemented to extend the predictions of the quark model to all q^2 values accesible in the physical decay. By comparison to the experimental data, we extract |V_ub

Michael Grady

Simulations of pure-gauge SU(2) lattice gauge theory are performed in the minimal Coulomb gauge. This leaves a residual or remnant gauge symmetry still active which is global in three directions but still local in one. Using averaged fourth-dimension pointing links as a spin-like order parameter, the remnant symmetry appears to undergo spontaneous symmetry b

K. Petrov

We calculate the free energy of a static quark anti-quark pair and the renormalized Polyakov loop in 2+1- and 3- flavor QCD using $16^3 \times 4$ and $16^3 \times 6$ lattices and improved staggered p4 action. We also compare the renormalized Polyakov loop with the results of our earlier studies.

F. de Soto, J. Carbonell

The numerical solutions of the non-relativistic Yukawa model on a 3-dimensional size lattice with periodic boundary conditions are obtained. The possibility to extract the corresponding -- infinite space -- low energy parameters and bound state binding energies from eigensates computed at finite lattice size is discussed.

C. Alexandrou, G. Koutsou, H. Neff

Gauge invariant density-density correlators yield detailed information on hadron structure. Hadron deformation and form factors can be extracted for momentum transfers up to about 6 GeV$^2$. We use stochastic techniques and dilution to compute the all to all propagator required for the exact evaluation of density-density correlators. We present first results

N. Ukita, S. Ejiri, T. Hatsuda, N. Ishii

We study the phase structure of QCD at finite temperatures with two flavors of dynamical quarks on a lattice with the size $N_s^3 \times N_t=16^3 \times 4$, using a renormalization group improved gauge action and a clover improved Wilson quark action. The simulations are made along the lines of constant physics determined in terms of $m_{\rm PS}/m_{\rm V}$ a

JLQCD Collaboration, T. Kaneko, S. Aoki, H. Fukaya

We present an overview of our project of large-scale simulations with dynamical overlap fermions. The first production run in two-flavor QCD is on-going using the Iwasaki gauge action on a 16^3 \times 32 lattice at the lattice spacing of 0.12fm with six sea quark masses down to m_{s,phys}/6, where m_{s,phys} is the physical strange quark mass. We briefly int

Jim Napolitano

We review the most recent results from experiments studying systems containing charmed quarks. The selection reflects the presenter's bias, and there is an emphasis on decays of open charm. We discuss precision measurements of various sorts, various new states in the charmonium system, measurements aimed at testing Lattice QCD, and the latest searches fo

G. S. Huang, CLEO Collaboration

We measure the inclusive branching fractions of charm mesons into three mesons with large s-anti-s content, namely the eta, eta' and phi. Data were accumulated with the CLEO-c detector. For D0 and D+ rates, we use 281/pb taken on the psi(3770) resonance, and for Ds+ rates, we use 195/pb taken at 4170 MeV. We find that the production rates of these partic

Katherine A. George

This article summarises measurements of time-dependent CP asymmetries in decays of neutral B mesons to charm final states using data collected by the BaBar detector at the PEP-II asymmetric-energy B-factory. All results are preliminary unless otherwise stated.

Owen Long

I present a review of using rare B decays to search for physics beyond the Standard Model. B decays that proceed either through annihilation or loop topologies at leading order in the Standard Model provide unique probes in the search for new physics. The latest experimental results from the B factories (Babar and Belle) and the Tevatron experiments (CDF and

Saurya Das, Anindya Dey, Soumitra SenGupta

We show that when the antisymmetric Kalb-Ramond field is included in the Randall-Sundrum scenario, although the hierarchy problem can be solved, it requires an extreme fine tuning of the Kalb-Ramond field (about 1 part in $10^{62}$). We interpret this as the return of the problem in disguise. Further, we show that the Kalb-Ramond field induces a small negati

Jerzy Matyjasek

The approximate renormalized one-loop effective action of the quantized massive scalar, spinor and vector field in a large mass limit, i.e., the lowest order of the DeWitt-Schwinger expansion involves the coincidence limit of the Hadamard-DeWitt coefficient a3. Building on this and using Wald's approach we shall construct the general expression describin

Christian Reisswig, Nigel T. Bishop, Chi Wai Lai, Jonathan Thornburg

The characteristic approach to numerical relativity is a useful tool in evolving gravitational systems. In the past this has been implemented using two patches of stereographic angular coordinates. In other applications, a six-patch angular coordinate system has proved effective. Here we investigate the use of a six-patch system in characteristic numerical r

Tim Koslowski

We investigate the action of diffeomorphisms in the context of Hamiltonian Gravity. By considering how the diffeomorphism-invariant Hilbert space of Loop Quantum Gravity should be constructed, we formulate a physical principle by demanding, that the gauge-invariant Hilbert space is a completion of gauge- (i.e. diffeomorphism-)orbits of the classical (configu

Mathys Walma

This paper discusses a method for pipelining the calculation of CRC's, such as ITU/CCITT CRC32, into a mostly feed-forward architecture. This method allows several benefits such as independent scaling of circuit frequency and data throughput. Additionally it allows calculation over packet tails (packet length not a multiple of CRC input width). Finally i

Simeon Warner, Jeroen Bekaert, Carl Lagoze, Xiaoming Liu

In the emerging eScience environment, repositories of papers, datasets, software, etc., should be the foundation of a global and natively-digital scholarly communications system. The current infrastructure falls far short of this goal. Cross-repository interoperability must be augmented to support the many workflows and value-chains involved in scholarly com

Donna M. Thompson, Alberto Accomazzi, Guenther Eichhorn, Carolyn Grant

The NASA Astrophysics Data System in conjunction with the Wolbach Library at the Harvard-Smithsonian Center for Astrophysics is working on a project to microfilm historical observatory publications. The microfilm is then scanned for inclusion in the ADS. The ADS currently contains over 700,000 scanned pages of volumes of historical literature. Many of these

Carolyn S. Grant, Alberto Accomazzi, Donna Thompson, Edwin Henneken

The Smithsonian/NASA ADS Abstract Service contains a wealth of data for astronomers and librarians alike, yet the vast majority of usage consists of rudimentary searches. Hints on how to obtain more focused search results by using more of the various capabilities of the ADS are presented, including searching by affiliation. We also discuss the classification

Olivier Zendra

Embedded systems become more and more widespread, especially autonomous ones, and clearly tend to be ubiquitous. In such systems, low-power and low-energy usage get ever more crucial. Furthermore, these issues also become paramount in (massively) multi-processors systems, either in one machine or more widely in a grid. The various problems faced pertain to a

Leah Epstein, Rob van Stee

We consider the machine covering problem for selfish related machines. For a constant number of machines, m, we show a monotone polynomial time approximation scheme (PTAS) with running time that is linear in the number of jobs. It uses a new technique for reducing the number of jobs while remaining close to the optimal solution. We also present an FPTAS for

Belynda Brahimi, Christophe Aubrun, Eric Rondeau

The Networked Control Systems (NCS) are complex systems which integrate information provided by several domians such as automatic control, computer science, communication network. The work presented in this paper concerns fault detection, isolation and compensation of communication network. The proposed method is based on the classical approach of Fault Dete

Farid Nouioua, Daniel Kayser

We develop a system which must be able to perform the same inferences that a human reader of an accident report can do and more particularly to determine the apparent causes of the accident. We describe the general framework in which we are situated, linguistic and semantic levels of the analysis and the inference rules used by the system.

Venkatesan Guruswami

Much progress has been made on decoding algorithms for error-correcting codes in the last decade. In this article, we give an introduction to some fundamental results on iterative, message-passing algorithms for low-density parity check codes. For certain important stochastic channels, this line of work has enabled getting very close to Shannon capacity with

A. Hoffmann, T. Jungk, E. Soergel

Commercial atomic force microscopes usually use a four-segmented photodiode to detect the motion of the cantilever via laser beam deflection. This read-out technique enables to measure bending and torsion of the cantilever separately. A slight angle between the orientation of the photodiode and the plane of the readout beam, however, causes false signals in

P. G. Niklowitz, M. J. Steiner, G. G. Lonzarich, D. Braithwaite

We report low-temperature and high-pressure measurements of the electrical resistivity ρ(T) of the antiferromagnetic compound NiS_2 in its high-pressure metallic state. The form of ρ(T) suggests that metallic antiferromagnetism in NiS_2 is quenched at a critical pressure p_c=76+-5 kbar. Near p_c the temperature variation of ρ(T) is similar to that observed i

Pai-Yi Hsiao, Erik Luijten

We study the salt-dependent conformations of dilute flexible polyelectrolytes in solution via computer simulations. Low concentrations of multivalent salt induce the known conformational collapse of individual polyelectrolyte chains, but as the salt concentration is increased further this is followed by a reexpansion. We explicitly demonstrate that multivale

N. M. Plakida, V. S. Oudovenko

A microscopic theory for electronic spectrum of the CuO2 plane within an effective p-d Hubbard model is proposed. Dyson equation for the single-electron Green function in terms of the Hubbard operators is derived which is solved self-consistently for the self-energy evaluated in the noncrossing approximation. Electron scattering on spin fluctuations induced

M. Bahiana, S. Allende, F. S. Amaral, D. Altbir

The effect of dipolar interactions in hexagonal arrays of Ni nanowires has been investigated by means of Monte Carlo simulations combined with a scaling technique, which allows the investigation of the internal structure of the wires. A strong dependence of the coercivity and remanence on the distance between wires has been observed. At intermediate packing

Jaydip Das, Sangita S. Kalarickal, Kyoung-Suk Kim, Carl E. Patton

The magnetization (M) as a function of temperature (T) from 2 to 300 K and in-plane field (H) up to 1 kOe, room temperature easy and hard direction in-plane field hysteresis loops for fields between -100 and +100 Oe, and 10 GHz ferromagnetic resonance (FMR) profiles have been measured for a series of soft-magnetic nano-crystalline 50 nm thick Fe-Ti-N films m

M. H. Ernst, E. Trizac, A. Barrat

We study a generic class of inelastic soft sphere models with a binary collision rate $g^ν$ that depends on the relative velocity $g$. This includes previously studied inelastic hard spheres ($ν=1$) and inelastic Maxwell molecules ($ν=0$). We develop a new asymptotic method for analyzing large deviations from Gaussian behavior for the velocity distribution f

Leszek Bryja, Arkadiusz Wojs, Jan Misiewicz, Marek Potemski

In two-beam magneto-photoluminescence spectra of a two-dimensional valence hole gas we identify the three-level energy spectrum of a free positive trion with a field-induced singlet-triplet transition. The recombination spectrum of acceptor-bound trions is also detected, including a cyclotron replica corresponding to the hole shake-up process. The emergence

N. B. Kopnin, A. S. Mel'nikov, V. I. Pozdnyakova, D. A. Ryzhov

Electronic heat transport along the flux lines in a long ballistic mesoscopic superconductor cylinder with a radius of the order of several coherence lengths is investigated theoretically using both semiclassical approach and the full quantum-mechanical analysis of the Bogoliubov--de Gennes equations. The semiclassical approach is constructed analogously to

R. Stadler, S. Kubatkin, T. Bjornholm

Recent I/V curve measurements suggest that C60 molecules deposited in gold nanojunctions change their adsorption configuration when a finite voltage in a 2-terminal setting is applied. This is of interest for molecular electronics because a robust molecular transistor could be based on such junctions if the mechanism of the process is understood. We present

Oleg Derzhko, Vasyl Myhal

We use the density functional method to examine the properties of the nonuniform (two-phase) fluid of two-level atoms, a part of which is excited. Basing on the analysis of the equation of state of a gas of two-level atoms, a part of which is excited, we suggest a simple density functional of the grand thermodynamical potential. We use the proposed density f

Baoli Liu, Junren Shi, Wenxin Wang, Hongming Zhao

We observe the inverse spin Hall effect in a two-dimensional electron gas confined in AlGaAs/InGaAs quantum wells. Specifically, we find that an inhomogeneous spin density induced by the optical injection gives rise an electric current transverse to both the spin polarization and its gradient. The spin Hall conductivity can be inferred from such a measuremen

Mustafa Keskin, Osman Canko, Ersin Kantar

The dynamic phase transitions have been studied, within a mean-field approach, in the kinetic spin-1 Ising model Hamiltonian with arbitrary bilinear and biquadratic pair interactions in the presence of a time varying (sinusoidal) magnetic field by using the Glauber-type stochastic dynamics. The nature (first- or second-order) of the transition is characteriz

Jean-Michel Condre, Christian Ligoure, Luca Cipelletti

We study experimentally and theoretically the sedimentation of gels made of strongly aggregated colloidal particles, focussing on the long time behavior, when mechanical equilibrium is asymptotically reached. The asymptotic gel height is found to vary linearly with the initial height, a finding in stark contrast with a recent study on similar gels [Manley \t

Llorens Serra, David Sanchez

We analyze the linear conductance of a semiconductor quantum wire containing a region where a local Rashba spin-orbit interaction is present. We show that Fano lineshapes appear in the conductance due to the formation of quasi bound states which interfere with the direct transmission along the wire, a mechanism that we term the Fano-Rashba effect. We obtain

O. D. Jayakumar, I. K. Gopalakrishnan, K. Shasikala, S. K. Kulshreshtha

The effect of hydrogenation on magnetic properties of Zn0.85Co0.05Li0.10O nanoparticles is presented. It was found that the sample hydrided at room temperature (RT) showed weak ferromagnetism (FM) while that hydrided at 400oC showed robust ferromagnetism at room temperature. In both cases reheating the sample at 400oC in air converts it back into paramagneti

A. V. Khomenko, I. A. Lyashenko

Within the framework of Lorentz model for description of viscoelastic medium the influence of deformational defect of the shear modulus is studied on melting of ultrathin lubricant film confined between the atomically flat solid surfaces. The possibility of jump-like and continuous melting is shown. Three modes of lubricant behavior are found, which correspo

N. R. Wilson, O. A. Petrenko, G. Balakrishnan, P. Manuel

Inelastic neutron scattering measurements have been performed on single crystal samples of Co3V2O8 and Ni3V2O8. The magnetic system in these compounds is believed to be frustrated, as the magnetic ions Co2+ with S=3/2 and Ni2+ with S=1 adopt a buckled version of the Kagome lattice. Magnetic excitations have been observed in both samples using a time-of-fligh

Patrick Rinke, Abdallah Qteish, Momme Winkelnkemper, Dieter Bimberg

We have studied the electronic structure of InN and GaN employing G0W0 calculations based on exact-exchange density-functional theory. For InN our approach predicts a gap of 0.7 eV. Taking the Burnstein-Moss effect into account, the increase of the apparent quasiparticle gap with increasing electron concentration is in good agreement with the observed blue s

G. A. Ovsyannikov, P. Komissinskiy, I. V. Borisenko, Yu. V. Kislinskii

We report an investigation of current transport in Nb/Au/CaSrCuO/YBaCuO heterostructures including an antiferromagnetic interlayer (CaSrCuO). Epitaxial thin films of YBaCuO and CaSrCuO were grown by laser ablation on NdGaO substrates; the thicknesses of CaSrCuO films were 20 and 50 nm, and x=0.15 or 0.5. Our experimental results show that the superconducting

H. Amitsuka, K. Matsuda, I. Kawasaki, K. Tenya

The pressure-temperature phase diagram of the heavy-electron superconductor URu2Si2 has been reinvestigated by ac-susceptibility and elastic neutron-scattering (NS) measurements performed on a small single-crystalline rod (2 mm in diameter, 6 mm in length) in a Cu-Be clamp-type high-pressure cell (P < 1.1 GPa). At ambient pressure, this sample shows the weak

Sudeshna Chattopadhyay, Alokmay Datta, Avijit Das, Angelo Giglia

Transverse layering of molecular gyration spheres in spin-coated atactic polystyrene ($aPS$) films, for film thickness $R \leq$ 4$R_g$ ($R_g$ = unperturbed gyration radius), causes an increase in free energy that does not follow the $(R_g/R)^{-2}$ dependence of planar confinement and is explained by invoking a fixed-range, repulsive, modified Pöschl-Teller i

Katsuyoshi Matsushita, Ryoko Sugano, Akiyoshi Kuroda, Yusuke Tomita

We have investigated, by the Monte Carlo simulation, spin systems which represent moments of arrayed magnetic nanoparticles interacting with each other only by the dipole-dipole interaction. In the present paper we aim the understanding of finite size effects on the magnetic nanoparticles arrayed in hexagonal columns cut out from the close-packing structures

Tomoyoshi Ono, Ikuo Ichinose

In this paper, we introduce a Ginzburg-Landau (GL) theory for the extended-$s$ and d-wave superconductors (SC) in granular systems that is defined on a lattice. In contrast to the ordinary Abelian Higgs model (AHM) that is a GL theory for the s-wave SC, Cooper-pair field (Higgs field) is put on links of the lattice in the present model. By means of Monte-Car

Moritz Hiller, Tsampikos Kottos, T. Geisel

We consider a family of chaotic Bose-Hubbard Hamiltonians (BHH) parameterized by the coupling strength $k$ between neighboring sites. As $k$ increases the eigenstates undergo changes, reflected in the structure of the Local Density of States. We analyze these changes, both numerically and analytically, using perturbative and semiclassical methods. Although o

M. Huecker, M. v. Zimmermann, G. D. Gu

The influence of high electric fields on the charge stripe order in Nd1.67Sr0.33NiO4 was studied by means of simultaneous hard x-ray diffraction and electrical transport experiments. Direct measurements of the charge stripe satellite peaks in zero and high electric fields provide no evidence for a deformation or a sliding of the stripe lattice, which contrad

Keishi Kanada, Takehiro Saito, Akira Oosawa, Takayuki Goto

The ground state of the solid solution of the two spin gap systems (CH3)2CHNH3CuCl3 and (CH3)2CHNH3CuBr3 has been investigated by 1H-NMR. The existence of a magnetic ordering in the sample with the Cl-content x=0.85 was clearly demonstrated by a drastic splitting in a resonance line at low temperatures below TN=13.5K. The observed NMR spectra in the ordered

U. Krey

The paper is withdrawn by the author due to a recently discovered flaw in a basic proof.

Bing Zhang, Enwei Liang, Kim L. Page, Dirk Grupe

We systematically analyze the prompt emission and the early afterglow data of a sample of 31 GRBs detected by {\em Swift} before September 2005, and estimate the GRB radiative efficiency. BAT&#39;s narrow band inhibits a precise determination of the GRB spectral parameters, and we have developed a method to estimate these parameters with the hardness ratio i

D. Londish, S. M. Croom, J. Heidt, B. J. Boyle

We report on our further analysis of the expanded and revised sample of potential BL Lac objects (the 2BL) optically identified from two catalogues of blue-selected (UV excess) point sources, the 2dF and 6dF QSO Redshift Surveys (2QZ and 6QZ). The 2BL comprises 52 objects with no apparent proper motion, over the magnitude range 16.0 < bj< 20.0. Follow-up hig

A. Burrows, E. Livne, L. Dessart, C. D. Ott

In the context of 2D, axisymmetric, multi-group, radiation/hydrodynamic simulations of core-collapse supernovae over the full 180$^{\circ}$ domain, we present an exploration of the progenitor dependence of the acoustic mechanism of explosion. All progenitor models we have tested with our Newtonian code explode. We investigate the roles of the Standing-Accret

L. Tenorio

We consider the problem of estimating the parameter $\fnl$ in the standard local model of primordial CMB non-Gaussianity. We determine the properties of maximum likelihood (ML) estimates and show that the problem is not the typical ML estimation problem as there are subtle issues involved. In particular, The Cramer-Rao inequality is not applicable and the li

O. G. Benvenuto, R. D. Rohrmann, M. A. De Vito

Splaver and coworkers have measured the masses of the white dwarf and the neutron star components of the PSR J1713+0747 binary system pair by Shapiro Delay. We attempt to find the original configuration of this system performing a set of binary evolution calculations to simultaneously account for the masses of both stars and the orbital period. We considered

Ju Zhang, O. E. Bronson Messer, Alexei M. Khokhlov, Tomasz Plewa

The thermonuclear explosion of a massive white dwarf in a Type Ia supernova explosion is characterized by vastly disparate spatial and temporal scales. The extreme dynamic range inherent to the problem prevents the use of direct numerical simulation and forces modelers to resort to subgrid models to describe physical processes taking place on unresolved scal

G. J. Harris, A. E. Lynas-Gray, S. Miller, J. Tennyson

The primordial elements, H, He and Li are included in a low temperature equation of state and monochromatic opacity function. The equation of state and opacity function are incorporated into the stellar evolution code NG-ELMS, which makes use of a non-grey model atmosphere computed at runtime. NG-ELMS is used to compute stellar evolution models for primordia

E. Egami, G. H. Rieke, D. Fadda, D. C. Hines

We present the Spitzer/IRS mid-infrared spectrum of the infrared-luminous (L_{IR}=4e11 L_sun) brightest cluster galaxy (BCG) in the X-ray-luminous cluster Z3146 (z=0.29). The spectrum shows strong aromatic emission features, indicating that the dominant source of the infrared luminosity is star formation. The most striking feature of the spectrum, however, i

D. Narbutis, R. Stonkute, V. Vansevicius

We compare stellar photometry data in the South-West part of the M31 disk published by Magnier et al. (1992), Mochejska et al. (2001) and Massey et al. (2006) as the local photometric standards for the calibration of star cluster aperture photometry. Large magnitude and color differences between these catalogs are found. This makes one to be cautious in usin

Enrique Martinez-Gonzalez

Most of the cosmological information extracted from the CMB has been obtained through the power spectrum, however there is much more to be learnt from the statistical distribution of the temperature random field. We review some recent developments in the study of the Cosmic Microwave Background (CMB) anisotropies and present a description of the novel tools

D. Narbutis, V. Vansevicius, K. Kodaira, I. Sableviciute

We present the results of UBVRI broad-band aperture CCD photometry of 51 compact star clusters located in the South-West part of the M31 disk. The mean rms errors of all measured star cluster colors are less than 0.02 mag. In color vs. color diagrams the star clusters show significantly tighter sequences when compared with the photometric data from the compi

Antoine Letessier-Selvon, Pierre Auger Collaboration

We present the first results for anisotropy searches around the galactic center at EeV energies using data from the Pierre Auger Observatory. Our analysis, based on a substantially larger data set, do not support previous claim of anisotropy found in this region by the AGASA and Sugar experiment. Furthermore we place un upper limit on a possible point like s

Eric Agol, Jason H. Steffen

We present a combined analysis of all publicly available, visible HST observations of transits of the planet HD 209458b. We derive the times of transit, planet radius, inclination, period, and ephemeris. The transit times are then used to constrain the existence of secondary planets in the system. We show that planets near an Earth mass can be ruled out in l

F. Mattana, D. Gotz, M. Falanga, F. Senziani

4U 1954+319 was discovered 25 years ago, but only recently has a clear picture of its nature begun to emerge. We present for the first time a broad-band spectrum of the source and a detailed timing study using more than one year of monitoring data. The timing and spectral analysis was done using publicly available Swift, INTEGRAL, BeppoSAX, and RXTE/ASM data

G. Stratta, S. Basa, N. Butler, J. L. Atteia

In this work, we present a multi-wavelength study of XRF 040912, aimed at measuring its distance scale and the intrinsic burst properties. We performed a detailed spectral and temporal analysis of both the prompt and the afterglow emission and we estimated the distance scale of the likely host galaxy. We then used the currently available sample of XRFs with

Ioannis Contopoulos

The present work is our first attempt to understand the role of reconnection in the pulsar magnetosphere. Our discussion is based on the observationaly infered fact that, as the pulsar spins down, the region of closed corotating dipolar field lines grows with time. This implies that reconnection must take place in the magnetosphere. We argue that non-dissipa

I. E. Papadakis, W. Brinkmann, M. J. Page, I. McHardy

We use the data from a recent, 100 ksec XMM-Newton observation of the Narrow Line Seyfert 1 galaxy Ark 564 to obtain its time average, X-ray spectrum. The 3-11 keV spectrum is well fitted by a power-law of slope 2.43. We detect a weak (equivalent width ~80 eV) emission line at ~6.7 keV, which implies emission from ionized iron. There is no compelling evidenc

Eric I. Barnes, Liliya L. R. Williams, Arif Babul, Julianne J. Dalcanton

There is no accepted mechanism that explains the equilibrium structures that form in collisionless cosmological N-body simulations. Recent work has identified nonextensive thermodynamics as an innovative approach to the problem. The distribution function that results from adopting this framework has the same form as for polytropes, but the polytropic index i

M. Guainazzi, S. Bianchi, M. Dovciak

We present preliminary results on the properties of relativistically broadened Fe K-alpha lines in a collection of more then 100 Active Galactic Nuclei (AGN) observed by the XMM-Newton EPIC-pn camera. Our main conclusions can be summarized as follows: a) we detect broad lines in about 25% of the sample objects. This fraction increases to 42+/-13% if we consi

M. Wittkowski, J. P. Aufdenberg, T. Driebe, V. Roccatagliata

We present K-band interferometric and optical spectroscopic observations of Menkar obtained with the instruments VINCI and UVES at Paranal Observatory. Spherically symmetric PHOENIX stellar model atmospheres are constrained by comparison to our interferometric and spectroscopic data, and high-precision fundamental parameters of Menkar are obtained. Our high-

M. Wittkowski, C. A. Hummel, J. P. Aufdenberg, V. Roccatagliata

Aims: We present a comparison of the visual and NIR intensity profile of the M0 giant gamma Sagittae to plane-parallel ATLAS 9 as well as to plane-parallel & spherical PHOENIX model atmospheres. Methods: We use previously described visual interferometric data obtained with the NPOI in July 2000. We apply the recently developed technique of coherent integrati

Osamu Nagae, Koji S. Kawabata, Yasushi Fukazawa, Takuya Yamashita

We present optical linear spectropolarimetry of the microquasar LS I +61$^{\circ}$ 303. The continuum emission is mildly polarized (up to 1.3 %) and shows almost no temporal change. We find a distinct change of polarization across the H$α$ emission line, indicating the existence of polarization component intrinsic to the microquasar. We estimate the interste

L. Meyer, R. Schoedel, A. Eckart, V. Karas

Context: The supermassive black hole at the Galactic center, SgrA*, shows frequent radiation outbursts, often called &#39;flares&#39;. In the near-infrared some of these flares were reported as showing intrinsic quasi-periodicities. The flux peaks associated with the quasi-periodic behavior were found to be highly polarized. Aims: The aim of this work is to

D. Froebrich, A. Scholz, C. L. Raftery

We used star density maps obtained from 2MASS to obtain a sample of star clusters in the entire Galactic Plane with |b|<20deg. A total of 1788 star cluster candidates are identified in this survey. Among those are 681 previously known open clusters and 86 globular clusters. A statistical analysis indicates that our sample of 1021 new cluster candidates has a

D. S. Wiebe, W. D. Watson

The anisotropy of velocities in MHD turbulence is demonstrated explicitly by calculating the velocity gradients as a function of direction in representative simulations of decaying turbulence. It follows that the optical depths of spectral lines are anisotropic when there is MHD turbulence, and that this anisotropy influences the polarization characteristics

G. Altavilla, P. Ruiz-Lapuente, A. Balastegui, J. Mendez

We study intermediate--z SNe Ia using the empirical physical diagrams which enable to learn about those SNe explosions. This information can be very useful to reduce systematic uncertainties of the Hubble diagram of SNe Ia up to high z. The study of the expansion velocities and the measurement of the ratio $\mathcal{R}$(\SiII) allow to subtype those SNe Ia a

T. Hyvonen, J. K. Kotilainen, E. Orndahl, R. Falomo

We present near-infrared H-band imaging of 15 intermediate redshift (0.5<z<1) radio quiet quasars (RQQ) in order to characterize the properties of their host galaxies. We are able to clearly detect the surrounding nebulosity in 12 objects, whereas the object remains unresolved in three cases. For all the resolved objects, we find that the host galaxy is well

Frank M. Rieger, Valenti Bosch-Ramon, Peter Duffy

We consider the acceleration of energetic particles by Fermi processes (i.e., diffusive shock acceleration, second order Fermi acceleration, and gradual shear acceleration) in relativistic astrophysical jets, with particular attention given to recent progress in the field of viscous shear acceleration. We analyze the associated acceleration timescales and th

N. Lodieu, N. C. Hambly, R. F. Jameson, S. T. Hodgkin

We present first results from a deep (J = 18.7), wide-field (6.5 square degrees) infrared (ZYJHK) survey in the Upper Sco association conducted within the science verification phase of the UKIRT Infrared Deep Sky Survey Galactic Cluster Survey (GCS). Cluster members define a sequence well separated from field stars in the (Z-J,Z) colour-magnitude diagram. We

D. Schaerer, R. Pello, J. Richard, E. Egami

Observing the first galaxies formed during the reionisation epoch, i.e. approximately within the first billion years after the Big Bang, remains one of the challenges of contemporary astrophysics. Several efforts are being undertaken to search for such remote objects. Combining the near-IR imaging power of the VLT and the natural effect of strong gravitation

D. P. Stark, W. M. Goss, E. Churchwell, V. L. Fish

We present VLBA observations of 1667 MHz OH maser emission from the massive star formation region G5.89-0.39. The observations were phase referenced allowing the absolute positions of the masers to be obtained. The 1667 MHz masers have radial velocities that span ~50 km/s but show little evidence of tracing the bipolar molecular outflow, as has been claimed

Luc Dessart, John Hillier

We have incorporated time-dependent terms into the statistical and radiative equilibrium calculations of the non-LTE line-blanketed radiative transfer code CMFGEN. To illustrate the significant improvements in spectral fitting achieved for photospheric phase Type II SN, and to document the effects associated with time dependence, we model the outer 6.1Msun o

William F. Gilreath

Extensible markup language (XML) is a technology that has been much hyped, so that XML has become an industry buzzword. Behind the hype is a powerful technology for data representation in a platform independent manner. As a text document, however, XML suffers from being too bloated, and requires an XML parser to access and manipulate it. XString is an encodi

C. J. Olson Reichhardt, Kevin E. Bassler

Canalization of genetic regulatory networks has been argued to be favored by evolutionary processes due to the stability that it can confer to phenotype expression. We explore whether a significant amount of canalization and partial canalization can arise in purely random networks in the absence of evolutionary pressures. We use a mapping of the Boolean func

David J. Strozzi, Ed A. Williams, A. Bruce Langdon, Abraham Bers

1-D Eulerian Vlasov-Maxwell simulations are presented which show kinetic enhancement of stimulated Raman backscatter (SRBS) due to electron trapping in regimes of heavy linear Landau damping. The conventional Raman Langmuir wave is transformed into a set of beam acoustic modes [L. Yin et al., Phys. Rev. E 73, 025401 (2006)]. For the first time, a low phase v

Doreen Wackeroth

I give an overview of the theory status of predictions for single W and Z boson production at hadron colliders. I briefly report on work in progress for improvements necessary to match the anticipated high precision of electroweak measurements, such as the W mass and width, at the Fermilab Tevatron p anti-p and the CERN LHC pp colliders.

Prashanth Jaikumar, Bradley S. Meyer, Kaori Otsuki, Rachid Ouyed

We explore heavy-element nucleosynthesis by rapid neutron capture (r-process) in the decompressing ejecta from the surface of a neutron star. The decompression is triggered by a violent phase transition to strange quark matter (quark-nova scenario). The presence of neutron-rich large Z nuclei (40,95) < (Z,A) < (70,177), the large neutron-to-seed ratio, and t

Andrew R Liddle, Pia Mukherjee, David Parkinson, Yun Wang

We compute the Bayesian evidences for one- and two-parameter models of evolving dark energy, and compare them to the evidence for a cosmological constant, using current data from Type Ia supernova, baryon acoustic oscillations, and the cosmic microwave background. We use only distance information, ignoring dark energy perturbations. We find that, under vario

Vadim M. Uritsky, Maya Paczuski, Joseph M. Davila, Shaela I. Jones

An extended data set of extreme ultraviolet images of the solar corona provided by the SOHO spacecraft are analyzed using statistical methods common to studies of self-organized criticality (SOC) and intermittent turbulence (IT). The data exhibits simultaneous hallmarks of both regimes, namely power law avalanche statistics as well as multiscaling of structu

Dovi Poznanski, Dan Maoz, Avishay Gal-Yam

(abridged) Ongoing supernova (SN) surveys find hundreds of candidates, that require confirmation for their use. Traditional classification based on followup spectroscopy of all candidates is virtually impossible for these large samples. We present an automatic Bayesian classifying algorithm for supernovae, the SN-ABC. We rely solely on single-epoch multiband

Igor Prokhorenkov, Ken Richardson

Let $M$ be a compact Riemannian manifold endowed with an isometric action of a compact Lie group. The method of the Witten deformation is used to compute the virtual representation-valued equivariant index of a transversally elliptic, first order differential operator on $M$. The multiplicities of irreducible representations in the index are expressed in ter

Adam Amara, Alexandre Refregier

Weak lensing surveys provide a powerful probe of dark energy through the measurement of the mass distribution of the local Universe. A number of ground-based and space-based surveys are being planned for this purpose. Here, we study the optimal strategy for these future surveys using the joint constraints on the equation of state parameter wn and its evoluti

Gunther Roland

Heavy ion collisions at the Large Hadron Collider (LHC) will produce strongly interacting matter at unprecedented energy densities. At LHC collision energies, new hard probes of the dense initial collision system will become readily available. We present an overview of the capabilities of the Compact Muon Solenoid (CMS) detector to use these probes for a det

T. Mishra, Ramesh V. Pai, B. P. Das

We study the ground state quantum phase diagram for a two species Bose mixture in a one-dimensional optical lattice using the finite size density matrix renormalization group(FSDMRG) method. We discuss our results for different combinations of inter and intra species interaction strengths with commensurate and incommensurate fillings of the bosons. The phase