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February 2009 arXiv papers — page 16

Showing 1,5011,600 of 4,929 papers

  1. Takuma Matsumoto, Tomoaki Egami, Kazuyuki Ogata, Masanobu Yahiro

    We present a practical way of smoothing discrete breakup S-matrix elements calculated by the continuum-discretized coupled-channel method (CDCC). This method makes the smoothing procedure much easier. The reliability of the smoothing method is confirmed for the three-body breakup reactions, 58Ni(d,pn) at 80 MeV and 12C(6He,4He2n) at 229.8 MeV.

  2. Yingda Cheng, Irene M. Gamba, Armando Majorana, Chi-Wang Shu

    In this paper, we present results of a discontinuous Galerkin (DG) scheme applied to deterministic computations of the transients for the Boltzmann-Poisson system describing electron transport in semiconductor devices. The collisional term models optical-phonon interactions which become dominant under strong energetic conditions corresponding to nano-scale a

  3. Mark Burgin, Gordana Dodig-Crnkovic

    Agents and agent systems are becoming more and more important in the development of a variety of fields such as ubiquitous computing, ambient intelligence, autonomous computing, intelligent systems and intelligent robotics. The need for improvement of our basic knowledge on agents is very essential. We take a systematic approach and present extended classifi

  4. Yositake Takane

    We theoretically study nonequilibrium spin transport in a superconducting wire connected by tunnel junctions to two ferromagnetic metal wires, each of which serves as an injector or detector of spin-polarized electron current. We present a set of Boltzmann equations to determine nonequilibrium quasiparticle distributions in this system, and obtain an analyti

  5. C. Forssen, J. Christensson, P. Navratil, S. Quaglioni

    This contribution reviews a number of applications of the ab initio no-core shell model (NCSM) within nuclear physics and beyond. We will highlight a nuclear-structure study of the A = 12 isobar using a chiral NN + 3NF interaction. In the spirit of this workshop we will also mention the new development of the NCSM formalism to describe open channels and to a

  6. Ross P. Church, Johann Dischler, Melvyn B. Davies, Christopher A. Tout

    To measure the onset of mass transfer in eccentric binaries we have developed a two-phase SPH technique. Mass transfer is important in the evolution of close binaries, and a key issue is to determine the separation at which mass transfer begins. The circular case is well understood and can be treated through the use of the Roche formalism. To treat the eccen

  7. Vladimir S. Mashkevich

    A solution to the dark matter problem is set forth in the framework of reductive semiclassical gravity, i.e., semiclassical gravity involving quantum state reduction. In that theory, the Einstein equation includes the energy-momentum tensor originating from pseudomatter and partially compensating for quantum jumps of the matter energy-momentum tensor. The co

  8. L Jeganathan, R Rama, Ritabrata Sengupta

    In this paper, we propose a new operation, Generalised Sequential Crossover (GSCO) of words, which in some sense an abstract model of crossing over of the chromosomes in the living organisms. We extend GSCO over language $L$ iteratively ($GSCO^*(L)$ as well as iterated GSCO over two languages $GSCO^*(L_1,L_2)$). Our study reveals that $GSCO^*(L)$ is subclass

  9. BES collaboration

    Using 58$\times 10^{6}$ $\jpsi$ events collected with the Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC), the branching fractions of $\jpsi$ to $p\bar{p}η$ and $p\bar{p}\etap$ are determined. The ratio $\frac{Γ(\jpsi\rar\ppbη)}{Γ(\jpsi\rar\ppb)}$ obtained by this analysis agrees with expectations based on soft-pion theorem calc

  10. Chin-Fei Lee, Ming-Chien Hsu, Raghvendra Sahai

    Collimated fast winds (CFWs) have been proposed to operate during the post-AGB evolutionary phase (and even earlier during the late AGB phase), responsible for the shaping of pre-planetary nebulae (PPNs) and young planetary nebulae (PNs). This paper is a follow-up to our previous study of CFW models for the well-studied PPN CRL 618. Previously, we compared o

  11. Adrian Butscher

    The gluing technique is used to construct hypersurfaces in Euclidean space having approximately constant prescribed mean curvature. These surfaces are perturbations of unions of finitely many spheres of the same radius assembled end-to-end along a line segment. The condition on the existence of these hypersurfaces is the vanishing of the sum of certain integ

  12. Gregory C. Dente, Michael L. Tilton

    Using the Wentzel-Kramers-Brillouin method, we derive a modified form of the Thomas-Fermi approximation to electron density. This new result enables us to calculate the details of the self-consistent ion cores, as well as the ionization potentials for the first s-orbital bound to the closed-shell ion core of the Group III, IV and V elements. Next, we demonst

  13. Domenico D'Alessandro

    I obtain the dynamics of the continuous time quantum walk on a $d$-dimensional lattice, with periodic boundary conditions, as an appropriate limit of the dynamics of the discrete time quantum walk on the same lattice. This extends the main result of arXiv:quant-ph/0606050 which proved this limit for the infinite line. By highlighting the main features of the

  14. James S. Bullock, Manoj Kaplinghat, Andrew Fruchter, Marla Geha

    Over the past five years, searches in Sloan Digital Sky Survey data have more than doubled the number of known dwarf satellite galaxies of the Milky Way, and have revealed a population of ultra-faint galaxies with luminosities smaller than typical globular clusters, L ~ 1000 Lsun. These systems are the faintest, most dark matter dominated, and most metal poo

  15. Michael Hitrik, Karel Pravda-Starov

    For a class of non-selfadjoint semiclassical pseudodifferential operators with double characteristics, we study bounds for resolvents and estimates for low lying eigenvalues. Specifically, assuming that the quadratic approximations of the principal symbol of the operator along the double characteristics enjoy a partial ellipticity property along a suitable s

  16. Kira V. Khmelnytskaya, Vladislav V. Kravchenko

    We give an overview of recent advances in analysis of equations of electrodynamics with the aid of biquaternionic technique. We discuss both models with constant and variable coefficients, integral representations of solutions, a numerical method based on biquaternionic fundamental solutions for solving standard electromagnetic scattering problems, relations

  17. Sergei Kopeikin

    Lunar Laser Ranging (LLR) measurements are crucial for advanced exploration of the evolutionary history of the lunar orbit, the laws of fundamental gravitational physics, selenophysics and geophysics as well as for future human missions to the Moon. Current LLR technique measures distance to the Moon with a precision approaching one millimeter that strongly

  18. The HADES Collaboration, G. Agakishiev, A. Balanda, B. Bannier

    We present phase space distributions and multiplicities of K+, K- and phi mesons produced in Ar+KCl reactions at a kinetic beam energy of 1.756 AGeV and measured with the HADES spectrometer. The inverse slope parameters and yields of kaons supplement the systematics of previous measurements. The percentage of K- mesons coming fromphi decay is found to be 18+

  19. David Arthur, Rajeev Motwani, Aneesh Sharma, Ying Xu

    We study the use of viral marketing strategies on social networks to maximize revenue from the sale of a single product. We propose a model in which the decision of a buyer to buy the product is influenced by friends that own the product and the price at which the product is offered. The influence model we analyze is quite general, naturally extending both t

  20. Rahul Shetty, Jens Kauffmann, Scott Schnee, Alyssa A. Goodman

    We investigate the effect of line of sight temperature variations and noise on two commonly used methods to determine dust properties from dust continuum observations of dense cores. One method employs a direct fit to a modified blackbody SED; the other involves a comparison of flux ratios to an analytical prediction. Fitting fluxes near the SED peak produce

  21. Taner Yildirim

    We present a detailed first principles study of Fe-pnictides with particular emphasis on competing magnetic interactions, structural phase transition, giant magneto-elastic coupling and its effect on phonons. The exchange interactions $J_{i,j}(R)$ are calculated up to $\approx 12 $Å$. We find that $J_{i,j}(R)$ has an oscillatory character with an envelop dec

  22. Sang Pyo Kim

    Some field theoretical aspects, such as the effective action and Schwinger pair production, are critically reviewed in strong QED. The difference of the boundary conditions on the solutions of the field equation is discussed to result in the effective action both in the Coulomb and time-dependent gauge. Finally, the apparent spin-statistics inversion is also

  23. Nils Bruin, Kevin Doerksen

    In this paper we study genus 2 curves whose Jacobians admit a polarized (4,4)-isogeny to a product of elliptic curves. We consider base fields of characteristic different from 2 and 3, which we do not assume to be algebraically closed. We obtain a full classification of all principally polarized abelian surfaces that can arise from gluing two elliptic curves

  24. Ron Ferguson, Corneliu Hoffman, Florian Luca, Alina Ostafe

    We study the distribution of singular and unimodular matrices in sumsets in matrix rings over finite fields. We apply these results to estimate the largest prime divisor of the determinants in sumsets in matrix rings over the integers.

  25. Ivan Arraut Guerrero, Davide Batic, Marek Nowakowski

    We analyze the static and spherically symmetric perfect fluid solutions of Einstein field equations inspired by the non commutative geometry. In the framework of the non commutative geometry this solution is interpreted as a mini black hole which has the Schwarzschild geometry outside the event horizon, but whose standard central singularity is replaced by a

  26. The HADES Collaboration, G. Agakishiev, A. Balanda, B. Bannier

    HADES is a versatile magnetic spectrometer aimed at studying dielectron production in pion, proton and heavy-ion induced collisions. Its main features include a ring imaging gas Cherenkov detector for electron-hadron discrimination, a tracking system consisting of a set of 6 superconducting coils producing a toroidal field and drift chambers and a multiplici

  27. Martin Hairer, Charles Manson

    We consider a one-dimensional diffusion process with coefficients that are periodic outside of a finite 'interface region'. The question investigated in this article is the limiting long time / large scale behaviour of such a process under diffusive rescaling. Our main result is that it converges weakly to a rescaled version of skew Brownian motion,

  28. M. J. Martins, C. S. Melo

    We apply the algebraic Bethe ansatz developed in our previous paper \cite{CM} to three different families of U(1) integrable vertex models with arbitrary $N$ bond states. These statistical mechanics systems are based on the higher spin representations of the quantum group $U_q[SU(2)]$ for both generic and non-generic values of $q$ as well as on the non-compa

  29. Robert F. Allen, Flavia Colonna

    In this paper, we study the multiplication operators on the Bloch space of a bounded homogeneous domain in $\mathbb{C}^n$. Specifically, we characterize the bounded and the compact multiplication operators, establish estimates on the operator norm, and determine the spectrum. We prove that the only bounded multiplication operators on the Bloch space of the p

  30. Parsa Bakhtary

    We generalize Horrocks' criterion for the splitting of vector bundles on projective space. We establish an analogous splitting criterion for vector bundles on a class of smooth complex projective varieties of dimension at least four, over which every extension of line bundles splits.

  31. Ravi Vakil, Kirsten Wickelgren

    In topology, the notions of the fundamental group and the universal cover are closely intertwined. By importing usual notions from topology into the algebraic and arithmetic setting, we construct a fundamental group family from a universal cover, both of which are schemes. A geometric fiber of the fundamental group family (as a topological group) is canonica

  32. Joshua N. Winn, John Asher Johnson, Daniel Fabrycky, Andrew W. Howard

    We present photometric and spectroscopic observations of the 2009 Feb. 2 transit of the exoplanet XO-3b. The new data show that the planetary orbital axis and stellar rotation axis are misaligned, as reported earlier by Hebrard and coworkers. We find the angle between the sky projections of the two axes to be 37.3 +/- 3.7 deg, as compared to the previously r

  33. Thayne Currie

    Based on a suite of Monte Carlo simulations, I show that a stellar-mass dependent lifetime of the gas disks from which planets form can explain the lack of hot Jupiters/close-in giant planets around high-mass stars and other key features of the observed semimajor axis distribution of radial velocity-detected giant planets. Using reasonable parameters for the

  34. Fa-Min Chen, Yong-Shi Wu

    We introduce an anti-symmetric metric into a 3-algebra and call it a symplectic 3-algebra. The N=6, Sp(2N) X U(1) superconformal Chern-Simons-matter theory with SU(4) R-symmetry in three dimensions is constructed by specifying the 3-brackets in a symplectic 3-algebra. We also demonstrate that the N=6, U(M) X U(N) theory can be recast into this symplectic 3-a

  35. J. A. Keselman, A. Nusser, P. J. E. Peebles

    Numerical simulations of the effect of a long-range scalar interaction (LRSI) acting only on nonbaryonic dark matter, with strength comparable to gravity, show patterns of disruption of satellites that can agree with what is seen in the Milky Way. This includes the symmetric Sagittarius stellar stream. The exception presented here to the Kesden and Kamionkow

  36. A. R. Fazely, R. M. Gunasingha, R. L. Imlay, K. D. Muhammad

    We investigate the discovery potential of cubic kilometer neutrino observatories such as IceCube to set stringent limits on the forbidden decays $η\toν_e\barν_e$ and $η\toν_τ\barν_τ$. The signatures for these decays are cascade events resulting from the charged-current reactions of $ν_e, ν_τ$, $\barν_e$ and $\barν_τ$ on nuclei in such detectors. Background c

  37. Ryo Suzuki

    We consider classical string spectrum of R x CP^3, and construct a family of solutions with residual SU(2) symmetry by the dressing method on SU(4)/U(3) sigma model. All of them obey the square-root type dispersion relation, as is expected from the su(2|2) symmetry. A single dyonic giant magnon is not found in this approach.

  38. Carl McBride

    A new metric is introduced, inspired by the Hirsch {\it h-index}, to measure the impact of a wiki site. A table of wikiFactors is presented for a number of wikis, in particular those oriented towards scientific topics. The wikiFactor is defined as the number of web pages, wF, that have had $\ge 1000$wF visits.

  39. Luiz C. L. Botelho

    We present physical arguments based on loop space representations for Dirac/Klein gordon determinants that some suitable Fermionic String Ising models at the critical point and defined on the space-time base manifold are formal quantum states of the gravitational field when quantized in the Ashtekar-Sen connection canonical formalism .These results complemen

  40. Elsen Veli Veliev, Gulsah Kaya

    In the present work, $D_{s}$ and $B_{s}$ meson parameters are investigated in the framework of thermal QCD sum rules. The temperature dependence of the mass and the leptonic decay constants are investigated by using Borel transform sum rules and Hilbert moment sum rules. To increase sensitivity, the vacuum contributions are subtracted from thermal expression

  41. Douglas Scott, Adam Moss

    The temperature of the atomic matter in the Universe is held to that of the Cosmic Background radiation until decoupling at z~100. After this it cools faster than the radiation (\propto(1+z)^2 rather than (1+z)) and would have fallen to about 20mK today if astrophysical feedback processes had not heated up the interglactic medium. We show how the derivative

  42. Reza Asgari, T. Gokmen, B. Tanatar, Medini Padmanabhan

    We present numerical calculations of the electron effective mass in an interacting, ferromagnetic, two-dimensional electron system. We consider quantum interaction effects associated with the charge-density fluctuation induced many-body vertex corrections. Our theory, which is free of adjustable parameters, reveals that the effective mass is suppressed (rela

  43. Mukul S. Laad, Luis Craco

    The precise nature of unconventional superconductivity in Iron Pnictides is presently a hotly debated issue. Here, using insights from normal state electronic structure and symmetry arguments, we show how an unconventional SC emerges from the bad metal "normal" state. Short-ranged, multi-band spin- and charge correlations generates nodeless SC in the

  44. Andrey Katz, Raman Sundrum

    Recently Arkani-Hamed, Finkbeiner, Slatyer and Weiner proposed a unified explanation to the set of experimental and observational anomalies with possible connections to Dark Matter (DM). A central role is played by GeV scale "dark" gauge bosons exchanged by the weak scale DM. Motivated by this proposal, we build an explicit model of DM in the context of Weak

  45. Guillaume Bal, Alexandre Jollivet

    This paper concerns the reconstruction of the absorption and scattering parameters in a time-dependent linear transport equation from knowledge of angularly averaged measurements performed at the boundary of a domain of interest. We show that the absorption coefficient and the spatial component of the scattering coefficient are uniquely determined by such me

  46. Cecilia Tarantino

    We present the update of the Unitarity Triangle (UT) analysis within the Standard Model (SM) and beyond. Within the SM, combining the direct measurements on sides and angles, the UT turns out to be overconstraint in a consistent way, showing that the CKM matrix is the dominant source of flavour mixing and CP-violation and that New Physics (NP) effects can ap

  47. Yishay Mansour, Mehryar Mohri, Afshin Rostamizadeh

    This paper addresses the general problem of domain adaptation which arises in a variety of applications where the distribution of the labeled sample available somewhat differs from that of the test data. Building on previous work by Ben-David et al. (2007), we introduce a novel distance between distributions, discrepancy distance, that is tailored to adaptat

  48. Hyun Kyu Lee, Mannque Rho

    With the explicit breaking of scale invariance by the trace anomaly of QCD rephrased in terms of spontaneous breaking, low-energy strong interaction dynamics of dense (and also hot) matter can be effectively captured by -- in addition to the Nambu-Goldstone bosons and the vector mesons -- two dilaton fields, the "soft" ($\chi_s$) field that is locked to chir

  49. Francis Oger

    In the present paper, as we did previously in [7], we investigate the relations between the geometric properties of tilings and the algebraic properties of associated relational structures. Our study is motivated by the existence of aperiodic tiling systems. In [7], we considered tilings of the euclidean spaces of finite dimension, and isomorphism was define

  50. J. Guardia, J. Montes, E. Nart

    Let $A$ be a Dedekind domain, $K$ the fraction field, $\p$ a non-zero prime ideal of $A$, and $K_\pp$ the completion of $K$ with respect to the $\p$-adic topology. At the input of a monic irreducible separable polynomial, $f(x)\in A[x]$, Montes algorithm determines the factorization of $f(x)$ over $K_\pp[x]$, and it provides essential arithmetic information

  51. David Kazhdan, Yakov Varshavsky

    In this paper we prove the fundamental lemma for Deligne-Lusztig functions. Namely, for every Deligne-Lusztig function $\phi$ on a $p$-adic group $G$ we write down an explicit linear combination $\phi^H$ of Deligne-Lusztig functions on an endoscopic group $H$ such that $\phi$ and $\phi^H$ have ``matching orbital integrals''. In particular, we prove a conject

  52. S. K. Mishra, F. Radu, H. A. Dürr, W. Eberhardt

    Positive exchange bias has been observed in the Ni$_{81}$Fe$_{19}$/Ir$_{20}$Mn$_{80}$ bilayer system via soft x-ray resonant magnetic scattering. After field cooling of the system through the blocking temperature of the antiferromagnet, an initial conventional negative exchange bias is removed after training i. e. successive magnetization reversals, resultin

  53. Andrea Cortis, Andrea Zoia

    Recent laboratory experiments on solute migration in composite porous columns have shown an asymmetry in the solute arrival time upon reversal of the flow direction, which is not explained by current paradigms of transport. In this work, we propose a definition for the solute flux across sharp interfaces and explore the underlying microscopic particle dynami

  54. V. K. Ignatovich, Yu. N. Pokotilovski

    A new limit is presented on the axionlike coupling from the data on the ultracold neutrons depolarization in traps.

  55. Constantine Yannouleas, Uzi Landman

    Through the introduction of a class of appropriate translationally invariant trial wave functions, we show that the strong correlations in the lowest Landau level (LLL) reflect in finite systems the emergence of intrinsic point-group symmetries associated with rotations and vibrations of molecules formed through particle localization. This quantal molecular

  56. Clifford Cheung, Joshua T. Ruderman, Lian-Tao Wang, Itay Yavin

    We propose a model in which supersymmetric weak scale dark matter is charged under a U(1)_d dark gauge symmetry. Kinetic mixing between U(1)_d and hypercharge generates the appropriate hierarchy of scales needed to explain PAMELA and ATIC with a GeV scale force carrier and DAMA (or INTEGRAL) using the proposals of inelastic (or, respectively, exciting) dark

  57. Drazen Adamovic, Antun Milas

    A general method for constructing logarithmic modules in vertex operator algebra theory is presented. By utilizing this approach, we give explicit vertex operator construction of certain indecomposable and logarithmic modules for the triplet vertex algebra W(p) and for other subalgebras of lattice vertex algebras and their N=1 super extensions. We analyze in

  58. C. Fernandez-Ramirez, A. M. Bernstein, T. W. Donnelly

    The contribution of D waves to physical observables for neutral pion photoproduction in the near threshold region is studied. Heavy Baryon Chiral Perturbation Theory to one loop, and up to ${\cal O}(q^4)$, is used to account for the S and P waves, while D waves are added in an almost model-independent way using standard Born terms and vector mesons. It is fo

  59. J. Zanghellini, F. Wodlei, H. -H. von Gruenberg

    The biogenesis of lipid droplets (LD) in the yeast Saccharomyces cerevisiae was theoretically investigated on basis of a biophysical model. In accordance with the prevailing model of LD formation, we assumed that neutral lipids oil-out between the membrane leaflets of the endoplasmic reticulum (ER), resulting in LD that bud-off when a critical size is reache

  60. Jasper F. Kok, Daniel J. Lacks

    Insulating particles can become highly electrified during powder handling, volcanic eruptions, and the wind-blown transport of dust, sand, and snow. Measurements in these granular systems have found that smaller particles generally charge negatively, while larger particles charge positively. These observations are puzzling, since particles in these systems a

  61. Kerstin Helfrich, H. -W. Hammer

    Three-body systems with large scattering length display universal phenomena associated with a discrete scaling symmetry. These phenomena include resonant enhancement of three-body loss rates when an Efimov three-body resonance is at the scattering threshold. In particular, there can be resonant peaks in the atom-dimer relaxation rate for large positive scatt

  62. A. P. Balachandran, M. Martone

    We show how to get a non-commutative product for functions on space-time starting from the deformation of the coproduct of the Poincare' group using the Drinfel'd twist. Thus it is easy to see that the commutative algebra of functions on space-time (R^4) can be identified as the set of functions on the Poincare' group invariant under the right ac

  63. M. Buric, M. Wohlgenannt

    We define a two-dimensional noncommutative space as a limit of finite-matrix spaces which have space-time dimension three. We show that on such space the Grosse-Wulkenhaar (renormalizable) action has natural interpretation as the action for the scalar field coupled to the curvature. We also discuss a natural generalization to four dimensions.

  64. She-Sheng Xue

    We study the Quantum Regge Calculus of Einstein-Cartan theory to describe quantum dynamics of Euclidean space-time discretized as a 4-simplices complex. Tetrad field e_\mu(x) and spin-connection field \omega_\mu(x) are assigned to each 1-simplex. Applying the torsion-free Cartan structure equation to each 2-simplex, we discuss parallel transports and constru

  65. Boudewijn F. Roukema, Piotr T. Rozanski

    In a flat space, the global topology of comoving space can induce a weak acceleration effect similar to dark energy. Does a similar effect occur in the case of the Poincare dodecahedral space S^3/I^*? Does the effect distinguish the Poincare space from other well-proportioned spaces? The residual acceleration effect in the Poincare space is studied here usin

  66. Stephen C. Anco, Amanullah Dar

    For the Euler equations governing compressible isentropic fluid flow with a barotropic equation of state (where pressure is a function only of the density), local conservation laws in $n>1$ spatial dimensions are fully classified in two primary cases of physical and analytical interest: (1) kinematic conserved densities that depend only on the fluid density

  67. P. Buonsante, F. Massel, V. Penna, A. Vezzani

    We study a two-dimensional Bose-Hubbard model at a zero temperature with random local potentials in the presence of either uniform or binary disorder. Many low-energy metastable configurations are found with virtually the same energy as the ground state. These are characterized by the same blotchy pattern of the, in principle, complex nonzero local order par

  68. Zubeyir Cinkir

    We express the tau constant of a metrized graph in terms of the discrete Laplacian matrix and its pseudo inverse.

  69. Avraham Ben-Aroya, Amnon Ta-Shma

    The diamond norm is a norm defined over the space of quantum transformations. This norm has a natural operational interpretation: it measures how well one can distinguish between two transformations by applying them to a state of arbitrarily large dimension. This interpretation makes this norm useful in the study of quantum interactive proof systems. In this

  70. Grigori Olshanski

    We construct a family of Markov processes with continuous sample trajectories on an infinite-dimensional space, the Thoma simplex. The family depends on three continuous parameters, one of which, the Jack parameter, is similar to the beta parameter in random matrix theory. The processes arise in a scaling limit transition from certain finite Markov chains, t

  71. Kathryn Hess

    Hopf-Galois extensions of rings generalize Galois extensions, with the coaction of a Hopf algebra replacing the action of a group. Galois extensions with respect to a group $G$ are the Hopf-Galois extensions with respect to the dual of the group algebra of $G$. Rognes recently defined an analogous notion of Hopf-Galois extensions in the category of structure

  72. R. L. Aptekar, T. L. Cline, D. D. Frederiks, S. V. Golenetskii

    In 2008 August, the new soft gamma-ray repeater SGR 0501+4516 was discovered by Swift. The source was soon confirmed by several groups in space- and ground-based multi-wavelength observations. In this letter we report the analysis of five short bursts from the recently discovered SGR, detected with Konus-Wind gamma-ray burst spectrometer. Properties of the t

  73. T. Takahashi, N. Maeda, K. Ikematsu, K. Fujii

    We studied a feasibility of measuring Higgs boson pair production in a Photon Linear Collider. The optimum energy of gamma gamma collision was estimated with a realistic luminosity distribution. We also discussed simulation study for detecting the signal against W boson pair backgrounds.

  74. Jonas Andersen Seebach, Klaus Thomsen

    We prove that the unitary equivalence classes of extensions of C*_r(G) by any sigma-unital stable C"-algebra, taken modulo extensions which split via an asymptotic homomorphism, form a group which can be calculated from the universal coefficient theorem of KK-theory when G is a free product of a countable collection of amenable groups.

  75. S. Komossa, H. Zhou, A. Rau, M. Dopita

    The galaxy SDSSJ0952+2143 showed remarkable emission-line properties first reported in 2008 (paper I), which are the consequence of a powerful high-energy flare. Here we report follow-up observations of SDSSJ0952+2143, and discuss outburst scenarios in terms of stellar tidal disruption by a SMBH, peculiar variability of an AGN, and a supernova explosion. The

  76. L. I. Danilov

    We consider the Schrödinger operator in ${\mathbb R}^n$, $n\geq 3$, with the electric potential $V$ and the magnetic potential $A$ being periodic functions (with a common period lattice) and prove absolute continuity of the spectrum of the operator in question under some conditions which, in particular, are satisfied if $V\in L^{n/2}_{\mathrm {loc}}({\mathbb

  77. Vladimir I. Danilov, Alexander V. Karzanov, Gleb A. Koshevoy

    For the ordered set $[n]$ of $n$ elements, we consider the class $\Bscr_n$ of bases $B$ of tropical Plücker functions on $2^{[n]}$ such that $B$ can be obtained by a series of mutations (flips) from the basis formed by the intervals in $[n]$. We show that these bases are representable by special wiring diagrams and by certain arrangements generalizing rhombu

  78. Malte Avenhaus, Andreas Eckstein, Peter J. Mosley, Christine Silberhorn

    We demonstrate the implementation of a fiber-integrated spectrograph utilizing chromatic group velocity dispersion (GVD) in a single mode fiber. By means of GVD we stretch an ultrafast pulse in time in order to spectrally resolve single photons in the time domain, detected by single photon counting modules with very accurate temporal resolution. As a result,

  79. Sven van Teeffelen, Rainer Backofen, Axel Voigt, Hartmut Löwen

    The phase-field crystal model is by now widely used in order to predict crystal nucleation and growth. For colloidal solidification with completely overdamped individual particle motion, we show that the phase-field crystal dynamics can be derived from the microscopic Smoluchowski equation via dynamical density functional theory. The different underlying app

  80. Michael Caruana, Peter Friz, Harald Oberhauser

    We consider nonlinear parabolic evolution equations of the form $\partial_{t}u=F(t,x,Du,D^{2}u) $, subject to noise of the form $H(x,Du) \circ dB$ where $H$ is linear in $Du$ and $\circ dB$ denotes the Stratonovich differential of a multidimensional Brownian motion. Motivated by the essentially pathwise results of [Lions, P.-L. and Souganidis, P.E.; Fully no

  81. Claude Bardos, Jasmine S. Linshiz, Edriss S. Titi

    We present an alpha-regularization of the Birkhoff-Rott equation, induced by the two-dimensional Euler-alpha equations, for the vortex sheet dynamics. We show the convergence of the solutions of Euler-alpha equations to a weak solution of the Euler equations for initial vorticity being a finite Radon measure of fixed sign, which includes the vortex sheets ca

  82. Yuri Lyubarsky

    In relativistic, Poynting dominated outflows, acceleration and collimation are intimately connected. An important point is that the Lorentz force is nearly compensated by the electric force therefore the acceleration zone spans a large range of scales. We derived the asymptotic equations describing relativistic, axisymmetric MHD flows far beyond the light cy

  83. Abhishek Chaudhuri, Anupam Kundu, Dibyendu Roy, Abhishek Dhar

    We investigate the steady state heat current in two and three dimensional disordered harmonic crystals in a slab geometry, connected at the boundaries to stochastic white noise heat baths at different temperatures.The disorder causes short wavelength phonon modes to be localized so the heat current in this system is carried by the extended phonon modes which

  84. Antonio Vairo

    I review, in a personal perspective, the history of the theory of non-relativistic bound states in QED and QCD from the Bethe-Salpeter equation to the construction of effective field theories.

  85. Tim Netzer, Daniel Plaumann, Markus Schweighofer

    A linear matrix inequality (LMI) is a condition stating that a symmetric matrix whose entries are affine linear combinations of variables is positive semidefinite. Motivated by the fact that diagonal LMIs define polyhedra, the solution set of an LMI is called a spectrahedron. Linear images of spectrahedra are called semidefinite representable sets. Part of t

  86. Burra G. Sidharth

    In this paper we show how it is possible to obtain mass generation in the context of non Abelian gauge field theory, using a non commutative spacetime. This is further confirmed by the modified dispersion relation that results from such a geometry.

  87. Dominic Joyce, Yng-Ing Lee, Richard Schoen

    Let (M,w) be a compact symplectic 2n-manifold, and g a Riemannian metric on M compatible with w. For instance, g could be Kahler, with Kahler form w. Consider compact Lagrangian submanifolds L of M. We call L Hamiltonian stationary, or H-minimal, if it is a critical point of the volume functional under Hamiltonian deformations. It is called Hamiltonian stabl

  88. D. Haug, V. Hinkov, A. Suchaneck, D. S. Inosov

    We present a neutron-scattering study of the static and dynamic spin correlations in the underdoped high-temperature superconductor YBa(2)Cu(3)O(6.45) in magnetic fields up to 15 T. The field strongly enhances static incommensurate magnetic order at low temperatures and induces a spectral-weight shift in the magnetic-excitation spectrum. A reconstruction of

  89. John Schliemann

    Motivated by the hyperfine interaction of electron spins with surrounding nuclei, we investigate systems of central spins coupled to a bath of noninteracting spins in the framework of random matrix theory. With increasing number of central spins a transition from Poissonian statistics to the Gaussian orthogonal ensemble occurs which can be described by a gen

  90. Fei Liu, Zhong-can Ou-Yang

    We present a generalized integral fluctuation theorem (GIFT) for general diffusion processes using the Feynman-Kac and Cameron-Martin-Girsanov formulas. Existing IFTs can be thought of to be its specific cases. We interpret the origin of this theorem in terms of time-reversal of stochastic systems.

  91. Young Ki Cho, Jong-Ig Lee, Ki Young Kim

    For a narrow slit structure backed by a conducting strip which is taken as a representative example of an aperture-body resonance (ABR) problem, the transmission resonance condition (i.e., condition for maximum power transmission) and the transmission width (i.e., normalized maximum transmitted power through the slit) are found to be the same as those for na

  92. Dawn Archey

    In this paper we introduce an analog of the tracial Rokhlin property, called the {\emph {projection free tracial Rokhlin property}}, for $C^*$-algebras which may not have any nontrivial projections. Using this we show that if $A$ is an infinite dimensional stably finite simple unital $C^*$-algebra with stable rank one, with strict comparison of positive elem

  93. Gi-Chol Cho, Yoshimi Kanehata

    The forward-backward asymmetry of $b$-quark jets on the $Z$-pole measured at LEP/SLD experiments shows us -2.8-$σ$ deviation from the Standard Model (SM) prediction. We examine a possibility of Kaluza-Klein (KK) gluon to explain the $\afbb$ data in a scenario based on the warped extra dimension model by Randall and Sundrum. In this scenario, the KK gluon str

  94. Y. Ezawa, H. Iwasaki, Y. Ohkuwa, S. Watanabe

    We investigate whether the equivalence theorem in f(R)-type gravity is valid also in quantum theory. It is shown that, if the canonical quantization is assumed, equivalence does not hold in quantum theory.

  95. D. Wittman

    At many universities, astronomy is a popular way for non-science majors to fulfill a general education requirement. Because general-education astronomy may be the only college-level science course taken by these students, it is the last chance to shape the science attitudes of these future journalists, teachers, politicians, and voters. I report on an attemp

  96. S. V. Donskov, A. K. Likhoded, A. V. Luchinsky, V. D. Samoylenko

    The decay $η'\toηπ^{0}π^{0}$ is studied in the framework of isobar model. It is shown, that good agreement with the experiment is achieved if $a_0$- and $σ$-meson contributions are taken into account. The contribution of $a_0$-meson is dominant, but $σ$-meson is necessary to reproduce the form of experimental Dalitz plot. Instead of usual Breit-Wigner fo

  97. Ralph Blumenhagen, Mirjam Cvetic, Shamit Kachru, Timo Weigand

    We review recent progress in determining the effects of D-brane instantons in N=1 supersymmetric compactifications of Type II string theory to four dimensions. We describe the abstract D-brane instanton calculus for holomorphic couplings such as the superpotential, the gauge kinetic function and higher fermionic F-terms. This includes a discussion of multi-i

  98. A. Yamasaki, S. Imada, K. Takase, T. Muro

    We have investigated the electronic structures of newly discovered superconductor FeSe1-x by bulk-sensitive photoemission spectroscopy (PES). The large Fe 3d spectral weight is located in the vicinity of the Fermi level (EF) and it decreases steeply toward EF . Compared with results of band structure calculations, narrowing the Fe 3d band width and the energ

  99. Ki Young Kim

    The fundamental guided dispersion characteristics of guided light in a subwavelength dielectric slit channel embedded by two different plasmonic metals are investigated when varying the gap width. As a result, an overall and salient picture of the guided dispersion characteristics is obtained over a wide spectrum range below and above the plasma frequencies

  100. Yunxin Zhang

    Molecular motors are single macromolecules that generate forces at the piconewton range and nanometer scale. They convert chemical energy into mechanical work by moving along filamentous structures. In this paper, we study the velocity of two-head molecular motors in the framework of a mechanochemical network theory. The network model, a generalization of th