March 2008 arXiv papers — page 22

Zdeněk Stuchlík, Stanislav Hledík

The differences between the character of the Schwarzschild and Ernst spacetimes are illustrated by comparing the photon capture cones, and the embedding diagrams of the $t=\mathrm{const}$ sections of the equatorial planes of both the ordinary and optical reference geometry of these spacetimes. The non-flat asymptotic character of the Ernst spacetime reflects

The DELPHI Collaboration, J. Abdallah

A measurement of the W boson mass and width has been performed by the DELPHI collaboration using the data collected during the full LEP2 programme (1996-2000). The data sample has an integrated luminosity of 660 pb^-1 and was collected over a range of centre-of-mass energies from 161 to 209 GeV. Results are obtained by applying the method of direct reconstru

Zdeněk Stuchlík, Stanislav Hledík, Josef Juráň

Properties of the optical reference geometry related to Kerr-Newman black-hole and naked-singularity spacetimes are illustrated using embedding diagrams of their equatorial plane. Among all inertial forces defined in the framework of the optical geometry, just the centrifugal force plays a fundamental role in connection to the embedding diagrams because it c

Jeffrey D. P. Kenney, O. Ivy Wong, Anne Abramson, Justin H. Howell

We present the initial results from SPITSOV, the Spitzer Survey of Virgo, which includes MIPS and IRAC observations for a carefully selected sample of 44 Virgo cluster spiral and peculiar galaxies. SPITSOV is part of a multiwavelength campaign to understand the effects of the cluster environment on galaxy evolution. These Virgo galaxies are different from ga

Zdeněk Stuchlík

Interior solutions of Einstein's equations with a non-zero cosmological constant are given for static and spherically symmetric configurations of uniform density. The metric tensor and pressure are determined for both positive and negative values of the cosmological constant. Limits on the outer radius of the interior solutions are established. It is sho

Athena S. Sefat, Michael A. McGuire, Brian C. Sales, Rongying Jin

The crystal structure and numerous normal and superconducting state properties of layered tetragonal (P4/nmm) LaFeAsO, with F-doping of 11 %, are reported. Resistivity measurements give an onset transition temperature Tc = 28.2 K, and low field magnetic susceptibility data indicate bulk superconductivity. In applied magnetic field, analysis of the resistive

Vipin Samar, Sangeeta Patni

There is no denying that spreadsheets have become critical for all operational processes including financial reporting, budgeting, forecasting, and analysis. Microsoft Excel has essentially become a scratch pad and a data browser that can quickly be put to use for information gathering and decision-making. However, there is little control in how data comes i

N. Werner, A. Finoguenov, J. S. Kaastra, A. Simionescu

About half of the baryons in the local Universe are invisible and - according to simulations - their dominant fraction resides in filaments connecting clusters of galaxies in the form of low density gas with temperatures in the range of 10^5<T<10^7 K. The existence of this warm-hot intergalactic medium was never unambiguously proven observationally in X-rays

C. Zurita, M. Durant, M. A. P. Torres, T. Shahbaz

We present time-resolved photometry of the optical counterpart to the black hole candidate Swift J1753.5-0127, which has remained in the low/hard X-ray state and bright at optical/IR wavelengths since its discovery in 2005. At the time of our observations Swift J1753.5-0127 does not show a decay trend but remains stable at R=16.45 with a night to night varia

Nikolaos Diamantis, Ramesh Sreekantan

Higher order automorphic forms have recently been introduced to study important questions in number theory and mathematical physics. We investigate the connection between these functions and Chen&#39;s iterated integrals. Then using Chen&#39;s theory, we prove a structure theorem for automorphic forms of all orders. This allows us to define an analogue of a

F. Courbin, P. North, A. Eigenbrod, D. Chelouche

We report the first results of a spectroscopic search for Lyman alpha, envelopes around three z=4.5 radio-quiet quasars. Our observational strategy uses the FORS2 spectrograph attached to the UT1 of the Very Large Telescope (VLT) in the multi-slit mode. This allows us to observe simultaneously the quasars and several PSF stars. The spectra of the latter are

Alikram N. Aliev, Hakan Cebeci, Tekin Dereli

We present an exact solution describing a stationary and axisymmetric object with electromagnetic and dilaton fields. The solution generalizes the usual Kerr-Taub-NUT (Newman-Unti-Tamburino) spacetime in general relativity and is obtained by boosting this spacetime in the fifth dimension and performing a Kaluza-Klein reduction to four dimensions. We also dis

Thorsten Lisker, Zhanwen Han

The flux excess of elliptical galaxies in the far-ultraviolet can be reproduced by population synthesis models when accounting for the population of old hot helium-burning subdwarf stars. This has been achieved by Han and coworkers through a quantitative model of binary stellar evolution. Here, we compare the resulting evolutionary population synthesis model

G. J. D. Petrie

Coronal loop emission profiles are often of remarkably constant width along their entire lengths, contradicting expectations based on model coronal magnetic field strengths decreasing with height. Meanwhile Paul Bellan has produced a theoretical model in which an initially empty, twisted force-free loop, on being filled with plasma via upflow at each foot po

Goran Bjorck, Uffe Haagerup

When using a Groebner basis to solve the highly symmetric system of algebraic equations defining the cyclic p-roots, one has the feeling that much of the advantage of computerized symbolic algebra over hand calculation is lost through the fact that the symmetry is immediately ``thrown out&#39;&#39; by the calculations. In this paper, the problem of finding (

J. P. Marques, M. J. P. F. G. Monteiro, J. M. Fernandes

In this paper we present a grid of stellar evolution models, computed with an up-to-date physical description of the internal structure, using the Code d&#39;Evolution Stellaire Adaptatif et Modulaire (CESAM). The evolutionary sequences span from the pre-main sequence to the beginning of the Red Giant Branch and cover an interval of mass typical for low and

Victor Batyrev, Fatima Haddad

In this paper, we show that any 3-dimensional normal affine quasihomogeneous SL(2)-variety can be described as a categorical quotient of a 4-dimensional affine hypersurface. Moreover, we show that the Cox ring of an arbitrary 3-dimensional normal affine quasihomogeneous SL(2)-variety has a unique defining equation. This allows us to construct SL(2)-equivaria

Manuel Toharia

We consider a real scalar field with an arbitrary negative bulk mass term in a general 5D setup, where the extra spatial coordinate is a warped interval of size $πR$. When the 5D field verifies Neumann conditions at the boundaries of the interval, the setup will always contain at least one tachyonic KK mode. On the other hand, when the 5D scalar verifies Dir

Nilufer Koldan, Igor Prokhorenkov, Mikhail Shubin

We discuss semiclassical asymptotics for the eigenvalues of the Witten Laplacian for compact manifolds with boundary in the presence of a general Riemannian metric. To this end, we modify and use the variational method suggested by Kordyukov, Mathai and Shubin (2005), with a more extended use of quadratic forms instead of the operators. We also utilize some

J. C. Suarez, M. J. Goupil

The present paper provides a description of the oscillation code FILOU, its main features, type of applications it can be used for, and some representative solutions. The code is actively involved in CoRoT/ESTA exercises (this volume) for the preparation for the proper interpretation of space data from the CoRoT mission. Although CoRoT/ESTA exercises have be

György Darvas, Tamás F. Farkas

The paper introduces an alternative rishon model for a composite structure of quarks and leptons. The model builds matter from six basic blocks (and their antiparticles). For this reason it introduces new properties of rishons, called &#34;scents&#34;, that can take two values, called masculine and feminine scents, which can appear in three colours both. The

Gabriel Istrate, Madhav V. Marathe, S. S. Ravi

In (Istrate, Marathe, Ravi SODA 2001) we advocated the investigation of robustness of results in the theory of learning in games under adversarial scheduling models. We provide evidence that such an analysis is feasible and can lead to nontrivial results by investigating, in an adversarial scheduling setting, Peyton Young&#39;s model of diffusion of norms. I

David Jou, Michele Sciacca, Maria Stella Mongiovi&#39;

An equation previously proposed to describe the evolution of vortex line density in rotating counterflow turbulent tangles in superfluid helium is generalized to incorporate nonvanishing barycentric velocity and velocity gradients. Our generalization is compared with an analogous approach proposed by Lipniacki, and with experimental results by Swanson et al.

J. T. Wickramasinghe, W. M. Napier

We calculate the expected flux profile of comets into the planetary system from the Oort cloud arising from Galactic tides and encounters with molecular clouds. We find that both periodic and sporadic bombardment episodes, with amplitudes an order of magnitude above background, occur on characteristic timescales ~25-35 Myr. Bombardment episodes occurring pre

M. H. Siegel, M. D. Shetrone, M. Irwin

Willman 1 is a small low surface-brightness object identified in the Sloan Digital Sky Survey and tentatively classified as a very low luminosity dSph galaxy. Further study has supported this classification while hinting that it may be undergoing disruption by the Milky Way potential. In an effort to better constrain the nature of Willman 1, we present a com

Ana Hurtado

In this work, we study the stability of Hopf vector fields on Lorentzian Berger spheres as critical points of the energy, the volume and the generalized energy. In order to do so, we construct a family of vector fields using the simultaneous eigenfunctions of the Laplacian and of the vertical Laplacian of the sphere. The Hessians of the functionals are negat

Sándor Baran, Gyula Pap

A nearly unstable sequence of stationary spatial autoregressive processes is investigated, when the sum of the absolute values of the autoregressive coefficients tends to one. It is shown that after an appropriate norming the least squares estimator for these coefficients has a normal limit distribution. If none of the parameters equals zero than the typical

Yves Gallot, Pieter Moree, Huib Hommersom

Let a_n(k) be the kth coefficient of the nth cyclotomic polynomial Phi_n(x). As n ranges over the integers, a_n(k) assumes only finitely many values. For any such value v we determine the density of integers n such that a_n(k)=v. Also we study the average of the a_n(k). We derive analogous results for the kth Taylor coefficient of 1/Phi_n(x) (taken around x=

J. F. Helmboldt, R. A. M. Walterbos, T. Goto

We present the results of an effort to identify and study a sample of the likely progenitors of elliptical (E) and lenticular (S0) K+A galaxies. To achieve this, we have searched a sample ~11,000 nearby (m(r)<16) early-type galaxies selected by morphology from the Sloan Digital Sky Survey (SDSS) Main spectroscopic sample for actively star-forming E and S0 ga

Y. Hatta, E. Iancu, A. H. Mueller

Within the framework of the AdS/CFT correspondence, we study the time evolution of an energetic R-current propagating through a finite temperature, strongly coupled, N=4 SYM plasma and propose a physical picture for our results. In this picture, the current splits into a pair of massless partons, which then evolve via successive branchings, in such a way tha

Guy Barles, Pierre Cardaliaguet, Olivier Ley, Aurélien Monteillet

We are interested in nonlocal Eikonal Equations describing the evolution of interfaces moving with a nonlocal, non monotone velocity. For these equations, only the existence of global-in-time weak solutions is available in some particular cases. In this paper, we propose a new approach for proving uniqueness of the solution when the front is expanding. This

John Michael Nahay

The existence of linear differential resolvents for z^alpha for any root z of an ordinary polynomial with coefficients in a given ordinary differential field has been established, where alpha is an indeterminate constant with respect to the derivation of the given field. In this paper we consider several alphas. We will call a finite sum of indeterminate pow

Lance J. Dixon

I describe some recent developments in the understanding of gluon scattering amplitudes in N=4 super-Yang-Mills theory in the large-N_c limit. These amplitudes can be computed to high orders in the weak coupling expansion, and also now at strong coupling using the AdS/CFT correspondence. They hold the promise of being solvable to all orders in the gauge coup

F. Haberl, P. Eger, W. Pietsch, R. H. D. Corbet

To investigate candidates for Be/X-ray binaries in the Small Magellanic Cloud (SMC), we observed a region around the emission nebula N19 with XMM-Newton in October 2006. We analysed the EPIC data of the detected point sources to derive their spectral and temporal characteristics. We detected X-ray pulsations with a period of 25.550(2) s from the second-brigh

Maria-Paula Gomez-Aparicio

Let G be a locally compact group and rho a non-unitary finite dimensional representation of G. We consider tensor products of rho by some unitary representations of G in order to define two Banach algebras analogous to the group C*-algebras, C*(G) and C*_r(G). We calculate the K-theory of such algebras for a large class of groups satisfying the Baum-Connes c

P. Barthold, T. Luedtke, R. J. Haug

An atomic force microscope is used to structure a film of multilayer graphene. The resistance of the sample was measured in-situ during nanomachining narrow trenches. We found a reversible behavior in the electrical resistance which we attribute to the movement of dislocations. After several attempts also permanent changes are observed.

Laura Gastaldo, Raphaele Herbin, Jean-Claude Latché

We present in this paper a pressure correction scheme for the drift-flux model combining finite element and finite volume discretizations, which is shown to enjoy essential stability features of the continuous problem: the scheme is conservative, the unknowns are kept within their physical bounds and, in the homogeneous case (i.e. when the drift velocity van

G. S. Bisnovatyi-Kogan, O. Yu. Tsupko

The properties of the relativistic rings which show up in images of a source when a black hole lies between the source and observer are examined. The impact parameters are calculated, along with the distances of closest approach of the rays which form a relativistic ring, their angular sizes, and their &#34;magnification&#34; factors, which are much less tha

V. Straizys, V. Laugalys

Using the infrared photometry data extracted from the 2MASS, IRAS and MSX databases, 50 suspected young stellar objects (YSOs) are selected from about 37500 infrared objects in the 3x3 deg area with the center at Galactic longitude 142.5 deg and latitude +1.0 deg, in the vicinity of the young stellar object GL 490 in the dark cloud DoH 942 (Dobashi et al. 20

D. Makogon, N. de Jeu, C. Morais Smith

We study a set of crossed 1D systems, which are coupled with each other via tunnelling at the crossings. We begin with the simplest case with no electron-electron interactions and find that besides the expected level splitting, bound states can emerge. Next, we include an external potential and electron-electron interactions, which are treated within the Har

V. Straizys, V. Laugalys

Using infrared photometric data extracted from the 2MASS, IRAS and MSX databases, 142 suspected young stellar objects (YSOs) are selected from about 2 million stars in the Camelopardalis segment of the Milky Way limited by Galactic longitude 132-158 deg, latitude pm 12 deg. According to radial velocities of the associated CO clouds, the objects are attribute

Idan Goldenberg, David Burshtein

The error performance of the ensemble of typical LDPC codes transmitted over the binary erasure channel (BEC) is analyzed. In the past, lower bounds on the error exponents were derived. In this paper a probabilistic upper bound on this error exponent is derived. This bound holds with some confidence level.

Pascal Moyal

In this paper, we present a stability criterion for Processor Sharing queues, in which the throughput may depend on the number of customers in the system (in such cases such as interferences between the users). Such a system is represented by a point measure-valued stochastic recursion keeping track of the remaining processing times of the customers.

Hannu-Pekka Komsa, Eero Arola, Eric Larkins, Tapio T. Rantala

The GaAs/GaAsN interface band offset is calculated from first principles. The electrostatic potential at the core regions of the atoms is used to estimate the interface potential and align the band structures obtained from respective bulk calculations. First, it is shown that the present method performs well on the well-known conventional/conventional AlAs/G

Myung-Ho Bae, Jae-Hyun Park, Jae-Hyun Choi, Hu-Jong Lee

We report heating-compensated interlayer tunneling spectroscopy (ITS) performed on stacks of overdoped Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ intrinsic junctions, where most of bias-induced heating in the ITS was eliminated. The onset temperature of the pseudogap (PG), revealed in the hump structure of the electronic excitation spectra, reached nearly room temperatur

D I Abramov

The new representation of the Coulomb three-body wave function via the well-known solutions of the separable Coulomb two-centre problem $ϕ_j(ξ,η)=X_j(ξ)Y_j(η)$ is obtained, where $X_j(ξ)$ and $Y_j(η)$ are the Coulomb spheroidal functions. Its distinguishing characteristic is the coordination with the boundary conditions of the scattering problem below the th

Yum-Tong Siu

In the 80th birthday conference for Professor LU Qikeng in June 2006 I gave a talk on the analytic approach to the finite generation of the canonical ring for a compact complex algebraic manifold of general type. This article is my contribution to the proceedings of that conference from my talk. In this article I give an overview of the analytic proof and fo

Serge Galam

A two state model for opinion forming, which has proven heuristic power, is reviewed with a novel emphasis on the existence or absence of a threshold for the dynamics. Monitored by repeated small groups discussions floater agents update their opinion according to a local majority rule. A threshold makes the initial supports to flow towards eitheir one of two

D. S. Murphy, J. F. McCann

The states of a boson pair in a one-dimensional double-well potential are investigated. Properties of the ground and lowest excited states of this system are studied, including the two-particle wavefunction, momentum pair distribution and entanglement. The effects of varying both the barrier height and the effective interaction strength are investigated.

G. Van Hooydonk

While achiral Bohr atom theory cannot generate Hbar signatures, achiral Heitler-London bond theory can but its Hbar signatures must be detected. We show that the largest spectral signature to probe Hbar is the singlet-triplet splitting of 9,5 eV at r(0)=0,74 Angstrom, observed in the dihydrogen band spectrum. This large Hbar-signature, overlooked for nearly

Florin Avram, Nikolai Leonenko, Ludmila Sakhno

Many statistical applications require establishing central limit theorems for sums, integrals, or for quadratic forms of functions of a stationary process. A particularly important case is that of Appell polynomials, since the Appell expansion rank&#34; determines typically the type of central limit theorem satisfied by these functionals. We review and exten

S. Camalet

We derive the Joule expansion of an isolated perfect gas from the principles of quantum mechanics. Contrary to most studies of irreversible processes which consider composite systems, the gas many-body Hilbert space cannot be factorised into Hilbert spaces corresponding to interesting and ignored degrees of freedom. Moreover, the expansion of the gas into th

A. A. Coley, G. W. Gibbons, S. Hervik, C. N. Pope

We investigate solutions of the classical Einstein or supergravity equations that solve any set of quantum corrected Einstein equations in which the Einstein tensor plus a multiple of the metric is equated to a symmetric conserved tensor $T_{μν}$ constructed from sums of terms the involving contractions of the metric and powers of arbitrary covariant derivat

Erwann Delay

We prove local existence of solutions to the extended constant scalar curvature equations introduced by A. Butscher, in the asymptotically hyperbolic setting. This gives a new local construction of asymptotically hyperbolic metrics with constant scalar curvature.

T. A. Lozinskaya, A. V. Moiseev, N. Yu. Podorvanyuk, A. N. Burenkov

We have investigated the structure, kinematics, and emission spectrum of the ionized gas in the synchrotron superbubble in the irregular galaxy IC 10 based on observations with the 6-m Special Astrophysical Observatory telescope with the SCORPIO focal reducer in three modes: direct imaging in the [SII](6717+6731)A lines, long-slit spectroscopy, and spectrosc

Vincent Cavalier, Daniel Lehmann

We describe the global structure of holomorphic webs in codimension one, and in particular their singularity (caustic). Various concepts are introduced, which have no interest locally near a regular point, such as the type, the reducibility, the quasi-smoothness, the CI property (complete intersection), the dicriticity... We prove for instance that the algeb

Igor Drozdovsky, Andrew M. Hopkins, Antonio Aparicio, Carme Gallart

Given the many recent advances in our understanding of the star formation history (SFH) of the Local Group and other nearby galaxies, and in the evolution of star formation with redshift, we present a new comparison of the comoving space density of the star formation rate as a function of look-back time for the Local and Distant Universe. We update the Local

Piergiulio Katis, N. Sabadini, R. F. C. Walters

We give a precise mathematical account of partita doppia in terms of an algebraic structure on the bicategory of spans of reflexive graphs. (The paper was written in 1998.)

Tae-Wook Ko, Bard Ermentrout

We investigate coupled identical phase oscillators with scale-free distribution of coupling strength. It is shown that partially locked states can occur due to the inhomogeneity in coupling and some properties of the coupling function. Various quantities of the partially locked states are computed through a self-consistency argument and the values show good

D. Salart, A. Baas, J. A. W. van Houwelingen, N. Gisin

We report on a Bell experiment with space-like separation assuming that the measurement time is related to gravity-induced state reduction. Two energy-time entangled photons are sent through optical fibers and directed into unbalanced interferometers at two receiving stations separated by 18 km. At each station, the detection of a photon triggers the displac

J. Bagherian, A. Rahnamai Barghi

It is well known that the adjacency algebra of an association scheme has the standard character. In this paper we first define the concept of standard character for C-algebras and we say that a C-algebra has the {\it standard character condition} if it has the standard character. Then we investigate some properties of C-algebras which have the standard chara

M. Mishra, C. P. Singh

One of the most surprising results is to find that a consistent description of all the experimental results on particle multiplicities and particle ratios obtained from the lowest AGS to the highest RHIC energies is possible within the framework of a thermal statistical model. We propose here a thermodynamically consistent excluded-volume model involving an

Jérémy Bluteau, Sabine Coquillart, Yohan Payan, Edouard Gentaz

BACKGROUND: Learning to perform new movements is usually achieved by following visual demonstrations. Haptic guidance by a force feedback device is a recent and original technology which provides additional proprioceptive cues during visuo-motor learning tasks. The effects of two types of haptic guidances-control in position (HGP) or in force (HGF)-on visuo-

Evgeny Kh. Akhmedov, Werner Rodejohann

In the type I + II seesaw formula the mass matrix of light neutrinos m_nu receives contributions from the exchanges of both heavy Majorana neutrinos and SU(2)_L-triplet Higgs bosons. We propose a new parameterization for the Dirac-type Yukawa coupling matrix of neutrinos in this case, which generalizes the well known Casas-Ibarra parameterization to type I +

C. Grimaldi

Electronic bound states around charged impurities in two-dimensional systems with structural inversion asymmetry can be described in terms of a two-dimensional hydrogen atom in the presence of a Rashba spin-orbit interaction. Here, the energy levels of the bound electron are evaluated numerically as a function of the spin-orbit interaction, and analytic expr

Peter Schattschneider, Michael Stoeger-Pollach, Stefano Rubino, Matthias Sperl

Magnetic Circular Dichroism (MCD) is a standard technique for the study of magnetic properties of materials in synchrotron beamlines. We present here a new scattering geometry in the Transmission Electron Microscope through which MCD can be observed with unprecedented spatial resolution. A convergent electron beam is used to scan a multilayer Fe/Au sample an

Bijan Saha, Mihai Visinescu

A Bianchi type I string cosmological model in the presence of a magnetic flux is investigated. A few plausible assumptions regarding the parametrization of the cosmic string and magneto-fluid are introduced and some exact analytical solutions are presented.

A. A. Saharian

We investigate the fermionic condensate and the vacuum expectation values of the energy-momentum tensor for a massive spinor field in de Sitter spacetime with spatial topology $\mathrm{R}^{p}\times (\mathrm{S}^{1})^{q}$. Both cases of periodicity and antiperiodicity conditions along the compactified dimensions are considered. By using the Abel-Plana formula,

Parongama Sen

We consider navigation or search schemes on networks which have a degree distribution of the form $P(k) \propto \exp(-k^γ)$. In addition, the linking probability is taken to be dependent on social distances and is governed by a parameter $λ$. The searches are realistic in the sense that not all search chains can be completed. An estimate of $μ=ρ/s_d$, where

M. Wang, Kai Chang

We investigate theoretically the spin transport in two-terminal mesoscopic rings in the presence of both the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI). We find that the interplay between the RSOI and DSOI breaks the original cylindric symmetry of mesoscopic ring and consequently leads to the anisotropic spin trans

L. Vanzi, G. Cresci, E. Telles, J. Melnick

We present integral field spectroscopy in the near-infrared of the nearby starburst galaxy IIZw40. Our new observations provide an unprecedented detailed view of the interstellar medium and star formation of this galaxy. The radiation emitted by the galaxy is dominated by a giant HII region, which extends over an area of more than 400 pc in size. A few clust

M. Kaniber, A. Neumann, A. Laucht, M. Bichler

We present an efficiently pumped single photon source based on single quantum dots (QD) embedded in photonic crystal nanocavities. Resonant excitation of a QD via a higher order cavity mode results in a 100$\times$ reduced optical power at the saturation onset of the photoluminescence, compared with excitation at the same frequency, after the cavity mode is

Zuo-Bing Wu

In this paper, a method to construct topological template in terms of symbolic dynamics for the diamagnetic Kepler problem is proposed. To confirm the topological template, rotation numbers of invariant manifolds around unstable periodic orbits in a phase space are taken as an object of comparison. The rotation numbers are determined from the definition and

Takayuki Kawamata, Nobuo Takahashi, Tadashi Adachi, Takashi Noji

We have measured the thermal conductivity of the one-dimensional (1D) S=1/2 Heisenberg antiferromagnetic spin system of Sr2Cu1-xPdxO3 single crystals including nonmagnetic impurities of Pd2+. It has been found that the mean free path of spinons along the 1D spin chain at low temperatures is very close to the average length of finite spin chains between spin

Gelio Alves, Aleksey Ogurtsov, Yi-Kuo Yu

Summary: In anticipation of the individualized proteomics era and the need to integrate knowledge from disease studies, we have augmented our peptide identification software RAId DbS to take into account annotated single amino acid polymorphisms, post-translational modifications, and their documented disease associations while analyzing a tandem mass spectru

Jüri Lember, Alexey Koloydenko

The EM procedure is a principal tool for parameter estimation in the hidden Markov models. However, applications replace EM by Viterbi extraction, or training (VT). VT is computationally less intensive, more stable and has more of an intuitive appeal, but VT estimation is biased and does not satisfy the following fixed point property. Hypothetically, given a

Osamu Ikawa, Takashi Sakai, Hiroyuki Tasaki

In this paper we study tangentially degeneracy of the orbits of s-representations in the sphere. We show that an orbit of an s-representation is tangentially degenerate if and only if it is through a long root, or a short root of restricted root system of type G_2. Moreover these orbits provide many new examples of tangentially degenerate submanifolds which

Xiang Zhou, Cheng-Zheng Hu, Zhenyu Zhang, Ling Miao

We investigate the persistent spin currents in one- and two-dimensional electron systems with spin-orbit interaction in thermodynamics equilibrium at absolute zero temperature. The persistent spin current is the intrinsic one which is connected with the Berry phases in the configuration spaces of an electron system and winding numbers in the field configurat

M. Vahabi, G. R. Jafari

In recent years, the economic policy of privatization, which is defined as the transfer of property or responsibility from public sector to private sector, is one of the global phenomenon that increases use of markets to allocate resources. One important motivation for privatization is to help develop factor and product markets, as well as security markets.

Pengbo Li

We propose a scheme for the generation of two-mode entangled states between two spatially separated cavities. It utilizes a two-level atom sequentially coupling to two high-Q cavities with a strong classical driving field. It is shown that by suitably choosing the intensities and detunings of the fields and coherent control of the dynamics, several different

Lenore R. Mullin, James E. Raynolds

We present a systematic, algebraically based, design methodology for efficient implementation of computer programs optimized over multiple levels of the processor/memory and network hierarchy. Using a common formalism to describe the problem and the partitioning of data over processors and memory levels allows one to mathematically prove the efficiency and c

Bhubanjyoti Bhattacharya, Jonathan L. Rosner

New data on the decays of the charmed particles $D^0$, $D^+$, and $D_s$ to pairs of light pseudoscalar mesons $P$ allow the testing of flavor symmetry and the extraction of key amplitudes. Information on relative strong phases is obtained. One sees evidence for the expected interference between Cabibbo-favored and doubly-Cabibbo-suppressed decays in the diff

Shoji Kato

In previous papers, we have proposed a model that the high-frequency quasi-periodic oscillations (HF QPOs) observed in black-hole and neutron-star X-ray binaries are inertial-acoustic oscillations that are resonantly excited on a one-armed deformed disk by nonlinear couplings between the oscillations and the disk deformation. In this paper we show that in ad

Toshiro Hiranouchi

We develop class field theory of curves over $p$-adic fields which extends the unramified theory of S. Saito. The class groups which approximate abelian étale fundamental groups of such curves are introduced in the terms of algebraic $K$-groups by imitating G. Wiesend&#39;s class group for curves over finite fields.

I. V. Rozhansky, G. D. Fleishman, G. -L. Huang

We analyze a dense cluster of solar radio spikes registered at ~ 4.5 -- 6 GHz by the Purple Mountain Observatory spectrometer (Nanjing, China) operating in the 4.5 -- 7.5 GHz range with the 5 ms temporal resolution. To handle with the data from the spectrometer we developed a new technique utilizing a nonlinear multi-Gaussian spectral fit based on chi-square

Jean-Marie Droz

We extend an approach of Beliakova for computing knot Floer homology and implement it in a publicly available computer program. We review the main programming and optimization methods used. Our program is then used to check that the Floer homology of a prime non-alternating knot with less than 12 crossings has no torsion.

Daniel Juteau

The purpose of this article is to set foundations for decomposition numbers of perverse sheaves, to give some methods to calculate them in simple cases, and to compute them concretely in two situations: for a simple (Kleinian) surface singularity, and for the closure of the minimal non-trivial orbit in a simple Lie algebra. This work has applications to modu

Erminia Calabrese, Anze Slosar, Alessandro Melchiorri, George F. Smoot

Combined analyses of WMAP 3-year and ACBAR Cosmic Microwave Anisotropies angular power spectra have presented evidence for gravitational lensing >3 sigma level. This signal could provide a relevant test for cosmology. After evaluating and confirming the statistical significance of the detection in light of the new WMAP 5-year data, we constrain a new paramet

Oana Mihaela Drăgulete

We construct symplectic and Kähler ray reduced spaces and discuss their relation with the Marsden-Weinstein (point) reduction. This Kähler reduction is well defined even when the momentum value is not totally isotropic. The compatibility of the ray reduction with the cone construction and the Boothby-Wang fibration is presented. Using the compatibility with

Gregory Dobler, Charles R. Keeton, Adam S. Bolton, Scott Burles

Spectroscopic galaxy-galaxy lens searches are presently the most prolific method of identifying strong lens systems in large data sets. We study the probabilities associated with these lens searches, namely the probability of identifying a candidate with rogue [OII] emission lines in a galaxy&#39;s spectrum, and the probability that the candidate will show f

Shun-Pei Miao, R. P. Woodard

We present a relatively simple operator formalism which reproduces the leading infrared logarithm of the one loop quantum gravitational correction to the fermion mode function on a locally de Sitter background. This rule may serve as the basis for an eventual stochastic formulation of quantum gravity during inflation. Such a formalism would not only effect a

Jacob Fox, Benny Sudakov

Let \mathcal{F}_k denote the family of 2-edge-colored complete graphs on 2k vertices in which one color forms either a clique of order k or two disjoint cliques of order k. Bollobás conjectured that for every ε>0 and positive integer k there is an n(k,ε) such that every 2-edge-coloring of the complete graph of order n \geq n(k,ε) which has at least ε{n \choo

B. Neichel, F. Hammer, M. Puech, H. Flores

We present a first combined analysis of the morphological and dynamical properties for the Intermediate MAss Galaxy Evolution Sequence (IMAGES) sample. It is a representative sample of 52 z~0.6 galaxies with Mstell from 1.5 to 15 10^10Msun and possessing 3D resolved kinematics and HST deep imaging in at least two broad band filters. We aim at evaluate robust

HERMES Collaboration, A. Airapetian

A single-spin asymmetry was measured in the azimuthal distribution of pi+pi- pairs produced in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target. For the first time, evidence is found for a correlation between the transverse target polarization and the azimuthal orientation of the plane containing the two pions.The correspo

Zeev Dvir

A Kakeya set is a subset of F^n, where F is a finite field of q elements, that contains a line in every direction. In this paper we show that the size of every Kakeya set is at least C_n * q^n, where C_n depends only on n. This improves the previously best lower bound for general n of ~q^{4n/7}.

G. Belanger, F. Boudjema, A. Pukhov, A. Semenov

We present a new module of the micrOMEGAs package for the calculation of WIMP-nuclei elastic scattering cross sections relevant for the direct detection of dark matter through its interaction with nuclei in a large detector. With this new module, the computation of the direct detection rate is performed automatically for a generic model of new physics which

Nicolas Brunner, Nicolas Gisin, Sandu Popescu, Valerio Scarani

With the goal of gaining a deeper understanding of quantum non-locality, we decompose quantum correlations into more elementary non-local correlations. We show that the correlations of all pure entangled states of two qubits can be simulated without communication, hence using only non-signaling resources. Our simulation model works in two steps. First, we de

Andrei A. Fedorenko, Pierre Le Doussal, Kay Joerg Wiese

We give evidence that the functional renormalization group (FRG), developed to study disordered systems, may provide a field theoretic description for the loop-erased random walk (LERW), allowing to compute its fractal dimension in a systematic expansion in epsilon=4-d. Up to two loop, the FRG agrees with rigorous bounds, correctly reproduces the leading log

Yukinobu Toda

In this paper, we introduce new enumerative invariants of curves on Calabi-Yau 3-folds via certain stable objects in the derived category of coherent sheaves. We introduce the notion of limit stability on the category of perverse coherent sheaves, a subcategory in the derived category, and construct the moduli spaces of limit stable objects. We then define t

Aleksandar Ivić

The &#34;hybrid&#34; moments $$ \int_T^{2T}|ζ(1/2+it)|^k{(\int_{t-G}^{t+G}|ζ(1/2+ix)|^\ell dx)}^m dt $$ of the Riemann zeta-function $ζ(s)$ on the critical line $\Re s = 1/2$ are studied. The expected upper bound for the above expression is $O_ε(T^{1+ε}G^m)$. This is shown to be true for certain specific values of the natural numbers $k,\ell,m$, and the expl