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June 2009 arXiv papers — page 28

Showing 2,7012,800 of 5,471 papers

  1. Andrew Smith, Jeremy Bailey, J. H. Hough, Steven Lee

    We present an empirical analysis of the effectiveness of frame selection (also known as Lucky Imaging) techniques for high resolution imaging. A high-speed image recording system has been used to observe a number of bright stars. The observations were made over a wide range of values of D/r0 and exposure time. The improvement in Strehl ratio of the stellar i

  2. S. -H. Baek, M. J. Graf, A. V. Balatsky, E. D. Bauer

    We report the use of impurities to probe the hidden order parameter of the strongly correlated metal URu_2Si_2 below the transition temperature T_0 ~ 17.5 K. The nature of this order parameter has eluded researchers for more than two decades, but is accompanied by the development of a partial gap in the single particle density of states that can be detected

  3. Konstantinos Pelechrinis, Ioannis Broustis, Srikanth V. Krishnamurthy, Christos Gkantsidis

    Dense, unmanaged 802.11 deployments tempt saboteurs into launching jamming attacks by injecting malicious interference. Nowadays, jammers can be portable devices that transmit intermittently at low power in order to conserve energy. In this paper, we first conduct extensive experiments on an indoor 802.11 network to assess the ability of two physical layer f

  4. C. Berg, C. Vignat

    In this paper, we find an expression for the density of the sum of two independent $d-$dimensional Student $t-$random vectors $\mathbf{X}$ and $\mathbf{Y}$ with arbitrary degrees of freedom. As a byproduct we also obtain an expression for the density of the sum $\mathbf{N}+\mathbf{X}$, where $\mathbf{N}$ is normal and $\mathbf{X}$ is an independent Student $

  5. P. K. Pathak, S. Hughes

    We present a scheme for the fast generation of entangled photons from a single quantum dot coupled to a planar photonic crystal that support two orthogonally polarized cavity modes. We discuss ``within generation'' and ``across generation'' of entangled photons when both biexciton to exciton, and exciton to ground state transitions, are coupled through cavit

  6. Jean-Marc Bonnet-Bidaud, Francoise Praderie, Susan Whitfield

    This paper presents an analysis of the star atlas included in the medieval Chinese manuscript (Or.8210/S.3326), discovered in 1907 by the archaeologist Aurel Stein at the Silk Road town of Dunhuang and now held in the British Library. Although partially studied by a few Chinese scholars, it has never been fully displayed and discussed in the Western world. T

  7. J. Michael Owen

    We describe a modified form of Smoothed Particle Hydrodynamics (SPH) in which the specific thermal energy equation is based on a compatibly differenced formalism, guaranteeing exact conservation of the total energy. We compare the errors and convergence rates of the standard and compatible SPH formalisms on analytic test problems involving shocks. We find th

  8. H. Tian, E. Marsch, C. -Y. Tu, L. -D. Xia

    We study the height variations of the sizes of chromospheric and transition-region features in a small coronal hole and the adjacent quiet Sun, considering images of the intensity, Doppler shift, and non-thermal motion of ultraviolet emission lines as measured by SUMER, together with the magnetic field as obtained by extrapolation from photospheric magnetogr

  9. Alberto Filipuzzi, Gino Isidori

    We analyse the violations of lepton-flavour universality in the ratios B(P -> l nu)/B(P -> l' nu) using a general effective theory approach, discussing various flavour-symmetry breaking patterns of physics beyond the SM. We find that in models with Minimal Lepton Flavour Violation the effects are too small to be observed in the next generations of experi

  10. C. N. Ferreira, J. A. Helayël Neto, A. A. V. Paredes

    In this work, we study a $U(1) \times U(1) ^{\prime}-$ model that results from a dimensional reduction of the N=1-D=4 supersymmetric version of the Cremer-Scherk-Kalb-Ramond model with non-minimal coupling to matter. Field truncations are not carried out, two Abelian symmetries coexist and three vector fields are present; two of them are gauge bosons. Then,

  11. Marcel Urban, Francois Couchot, Sylvie Dagoret Campagne, Xavier Sarazin

    We are used to describe the detection of light in terms of particles and its propagation from the source to the detection, by waves. For instance, the slowing down of light in a transparent medium is always explained within the electromagnetic wave framework. We propose to approach that phenomenon through a purely corpuscular description. We find expression

  12. Michael J. Mortonson, Wayne Hu

    The CMB temperature power spectrum offers ambiguous evidence for the existence of horizon-scale power in the primordial power spectrum due to uncertainties in spatial curvature and the physics of cosmic acceleration as well as the observed low quadrupole. Current polarization data from WMAP provide evidence for horizon-scale power that is robust to these unc

  13. J. Kiskis, R. Narayanan

    We numerically compute the spatial string tension in the deconfined phase of three dimensional QCD in the large N limit. Our results clearly show that the string tension grows linearly with temperature.

  14. G. Baume, G. Carraro, Y. Momany

    We present optical ($UBVI_C$) observations of a rich and complex field in the Galactic plane towards $l \sim 305^{\circ}$ and $b \sim 0^{\circ}$. Our analysis reveals a significantly high interstellar absorbtion ($A_V \sim 10$) and an abnormal extinction law in this line of sight. Availing a considerable number of color combinations, the photometric diagrams

  15. H. Tian, C. -Y. Tu, E. Marsch, J. -S. He

    Aims. The physical implication of large blue shift of Ne viii in the quiet Sun region is investigated in this paper. Methods. We compare the significant Ne viii blue shifts, which are visible as large blue patches on the Doppler-shift map of a middlelatitude quiet-Sun region observed by SUMER, with the coronal magnetic-field structures as reconstructed from

  16. Renat Zhdanov

    We prove that any potential symmetry of a system of evolution equations reduces to a Lie symmetry through a nonlocal transformation of variables. Based on this fact is our method of group classification of potential symmetries of systems of evolution equations having non-trivial Lie symmetry. Next, we modify the above method to generate more general nonlocal

  17. Hui Tian, Werner Curdt, Eckart Marsch, Jiansen He

    We performed a systematic study of the Doppler shifts and electron densities measured in an EUV bright point (hereafter BP) observed in more than 10 EUV lines with formation temperatures from log (T/K) p 4.5 to 6.3. Those parts of a BP seen in transition region and coronal lines are defined as its cool and hot components, respectively. We find that the trans

  18. Alain Goupil

    I present a bijection on integer partitions that leads to recursive expressions, closed formulae and generating functions for the cardinality of certain sets of partitions of a positive integer $n$. The bijection leads also to a product on partitions that is associative with a natural grading thus defining a free associative algebra on the set of integer par

  19. Ariel Bendersky, Fernando Pastawski, Juan Pablo Paz

    In this paper we describe in detail and generalize a method for quantum process tomography that was presented in [A. Bendersky, F. Pastawski, J. P. Paz, Physical Review Letters 100, 190403 (2008)]. The method enables the efficient estimation of any element of the $χ$--matrix of a quantum process. Such elements are estimated as averages over experimental outc

  20. Avner Peleg, Yeojin Chung, Tomáš Dohnal, Quan M. Nguyen

    We investigate the statistics of flat-top solitary wave parameters in the presence of weak multiplicative dissipative disorder. We consider first propagation of solitary waves of the cubic-quintic nonlinear Schrödinger equation (CQNLSE) in the presence of disorder in the cubic nonlinear gain. We show by a perturbative analytic calculation and by Monte Carlo

  21. P. Mohr

    The cross sections of the $^3$He($α$,$α$)$^3$He and $^3$He($α$,$γ$)$^7$Be reactions are studied at low energies using a simple two-body model in combination with a double-folding potential. At very low energies the capture cross section is dominated by direct s-wave capture. However, at energies of several MeV the d-wave contribution increases, and the theor

  22. Hailiang Liu, James Ralston

    Computation of high frequency solutions to wave equations is important in many applications, and notoriously difficult in resolving wave oscillations. Gaussian beams are asymptotically valid high frequency solutions concentrated on a single curve through the physical domain, and superposition of Gaussian beams provides a powerful tool to generate more genera

  23. Julien Garaud, Mikhail S. Volkov

    We present a detailed analysis of classical solutions in the bosonic sector of the electroweak theory which describe vortices carrying a constant electric current ${\cal I}$. These vortices exist for any value of the Higgs boson mass and for any weak mixing angle, and in the zero current limit they reduce to Z strings. Their current is produced by the conden

  24. Julia Berashevich, Tapash Chakraborty

    We propose a unique way to control both bandgap and the magnetic properties of nanoscale graphene, which might prove highly beneficial for application in nanoelectronic and spintronic devices. We have shown that chemical doping by nitrogen along a single zigzag edge breaks the sublattice symmetry of graphene. This leads to the opening of a gap and a shift of

  25. R. Bistritzer, A. H. MacDonald

    We study non-linear dc transport in graphene using a hydrodynamic approach and conclude that in clean samples the drift velocity saturates at a weakly density-dependent value v_{sat} ~ 10^7 cm/s. We show that saturation results from the interactions between graphene's Dirac quasi-particles and both acoustic and optical phonons. Saturation is accompanied

  26. D. C. Stephens, S. K. Leggett, Michael C. Cushing, Mark S. Marley

    We present new 5.2-14.5 micron low-resolution spectra of 14 mid-L to mid-T dwarfs, as well as 3.0-4.1 micron spectra for five of these dwarfs. These data are supplemented by existing red and near-infrared spectra (0.6-2.5 micron), as well as red through mid-infrared spectroscopy of seven other L and T dwarfs presented by Cushing et al. (2008). We compare the

  27. Roberto Ferreiro Pérez, Jaime Muñoz Masqué

    Two examples of $\mathrm{Diff}^+S^1$-invariant closed two-forms obtained from forms on jet bundles, which does not admit equivariant moment maps are presented. The corresponding cohomological obstruction is computed and shown to coincide with a nontrivial Lie algebra cohomology class on $H^2(\mathfrak{X}(S^1))$.

  28. P. A. Baikov, K. G. Chetyrkin, J. H. Kühn

    We report on some technical aspects of our calculation of alpha_s^4 corrections to R(s) and the semi-leptonic tau decay width [1-3]. We discuss the inner structure of the result as well as the issue of its correctness. We demonstrate recently appeared independent evidence positively testing one of two components of the full result.

  29. Gennadiy Burlak, Isabel Sainz, Andrei B. Klimov

    We study the entanglement dynamics in a two-spin system governed by a bilinear Hamiltonian and assisted by phase kicks. It is found that the application of instant kicks to both spins at some specific moments leads to enhancement of entanglement. This procedure also improves the transient character of entanglement leading, for large spins, to a formation of

  30. Leandro M. Del Pezzo, Julián Fernández Bonder

    In this paper, we study the problem of minimizing the first eigenvalue of the $p-$Laplacian plus a potential with weights, when the potential and the weight are allowed to vary in the class of rearrangements of a given fixed potential $V_0$ and weight $g_0$. Our results generalized those obtained in [9] and [5].

  31. The CLEO Collaboration, D. Besson

    Using the entire CLEO-c ψ(3770)-> D\bar{D} event sample, corresponding to an integrated luminosity of $818 pb^-1 and approximately 5.4 million D\bar{D} events, we present a study of the decays D^0 -> π^- e^+ ν_e, D^0 -> K^- e^+ ν_e, D^+ -> π^0 e^+ ν_e, and D^+ -> \bar{K}^0 e^+ ν_e. Via a tagged analysis technique, in which one D is fully reconstructed in a h

  32. Masashi Kojo, Kikuji Hirose

    We develop a biorthogonal linear-scaling algorithm for a transcorrelated method based on the localized nature of transformed orbitals. The transcorrelated method, which employs a similarity-transformed Hamiltonian referred to as a transcorrelated Hamiltonian, enables highly accurate first-principles condensed-matter calculations in principle. Meanwhile, the

  33. Alexander A. Borisenko, Vicente Miquel

    Let $M$ be a complete Riemannian manifold which either is compact or has a pole, and let $φ$ be a positive smooth function on $M$. In the warped product $M\times_φ\mathbb R$, we study the flow by the mean curvature of a locally Lipschitz continuous graph on $M$ and prove that the flow exists for all time and that the evolving hypersurface is $C^\infty$ for $

  34. P. Brogueira, J. Dias de Deus, J. G. Milhano

    Saturation models -- colour glass condensate and string percolation -- impose a strict relation between the average transverse momentum, <P_T>, and the rapidity particle densities, dn/dy. By combining this relation with an appropriate evolution equation for dn/dy, and imposing energy-momentum conservation, we obtain a fair description of data, for generic AB

  35. E. Bayet, M. Gerin, T. G. Phillips, A. Contursi

    In this paper, we investigate the relevance of using the $^{12}$CO line emissions as indicators of star formation rates (SFR). For the first time, we present this study for a relatively large number of $^{12}$CO transitions (12) as well as over a large interval in redshift (from z$\sim$0 to z$\sim$6). For the nearby sources (D$\leq$10 Mpc), we have used homo

  36. K. Jin, X. H. Zhang, P. Bach, R. L. Greene

    We investigated the in-plane angular magnetoresistivity (AMR) of $% T^{^{\prime}}$-phase La$_{2-x}$Ce$_{x}$CuO$_{4}$ (LCCO) thin films ($% x=0.06-0.15$) fabricated by a pulsed laser deposition technique. The in-plane AMR with $\mathbf{H}\parallel ab$ shows a twofold symmetry instead of the fourfold behavior found in other electron-doped cuprates such as Pr$%

  37. Y. F. Niu, N. Paar, D. Vretenar, J. Meng

    The multipole response of nuclei at temperatures T=0-2 MeV is studied using a self-consistent finite-temperature RPA (random phase approximation) based on relativistic energy density functionals. Illustrative calculations are performed for the isoscalar monopole and isovector dipole modes and, in particular, the evolution of low-energy excitations with tempe

  38. Konstantine Zelator

    If o and * are two binary operations in a number system, then three elements a,b,c in that number system are said to satisfy the distributive property of the operation o over the operation * if, ao(b*c)= (aob)*(aoc) Now, suppose that the number system is the rationals,and the operations o and * are among the four usual operations of addition, multiplication,

  39. W. Zheng, J. Deng, M. Zhai, L. Xin

    A gamma-ray burst (GRB) optical photometric follow-up system at the Xinglong Observatory of National Astronomical Observatories of China (NAOC) has been constructed. It uses the 0.8-m Tsinghua-NAOC Telescope (TNT) and the 1-m EST telescope, and can automatically respond to GRB Coordinates Network (GCN)alerts. Both telescopes slew relatively fast, being able

  40. Richard Conn Henry

    A bright UV GALEX image in the direction of a dense high galactic latitude interstellar dust cloud is examined to test (and to reject) the idea that a bright extragalactic UV background radiation field exists. A GALEX &#34;Deep Imaging Survey&#34; image of a second high latitude region (a region almost totally free of dust) shows a similar bright background,

  41. Daniel Karapetyan, Gregory Gutin, Boris Goldengorin

    The multidimensional assignment problem (MAP) (abbreviated s-AP in the case of s dimensions) is an extension of the well-known assignment problem. The most studied case of MAP is 3-AP, though the problems with larger values of s have also a number of applications. In this paper we consider four fast construction heuristics for MAP. One of the heuristics is n

  42. B. Neethi Simon, Sudhavathani Simon, N. Mukunda, F. Gori

    The Mueller-Stokes formalism which governs conventional polarization optics is formulated for plane waves, and thus the only qualification one could demand of a $4\times 4$ real matrix $M$ in order that it qualifies to be the Mueller matrix of some physical system is that $M$ should map $Ω^{({\rm pol})}$, the positive cone of Stokes vectors, into itself. In

  43. Enric Palle, Maria Rosa Zapatero Osorio, Pilar Montanes-Rodriguez, Rafael Barrena

    Of the 342 planets discovered so far orbiting other stars, 58 &#34;transit&#34; the stellar disk, meaning that they can be detected by a periodic decrease in the starlight flux. The light from the star passes through the atmosphere of the planet, and in a few cases the basic atmospheric composition of the planet can be estimated. As we get closer to finding

  44. V. Yefremenko, G. Wang, V. Novosad, A. Datesman

    The thermal transport in partially trenched silicon nitride membranes has been studied in the temperature range from 0.3 to 0.6 K, with the transition edge sensor (TES), the sole source of membrane heating. The test configuration consisted of Mo/Au TESs lithographically defined on silicon nitride membranes 1 micron thick and 6 mm^2 in size. Trenches with var

  45. J. P. Bernstein, R. Kessler, S. Kuhlmann, H. Spinka

    We present simulations for the Dark Energy Survey (DES) using a new code suite (SNANA) that generates realistic supernova light curves accounting for atmospheric seeing conditions and intrinsic supernova luminosity variations using MLCS2k2 or SALT2 models. Errors include stat-noise from photo-statistics and sky noise. We applied SNANA to simulate DES superno

  46. S. Schmitz, A. Tilgner

    Numerical simulation of rotating convection in plane layers with free slip boundaries show that the convective flows can be classified according to a quantity constructed from the Reynolds, Prandtl and Ekman numbers. Three different flow regimes appear: Laminar flow close to the onset of convection, turbulent flow in which the heat flow approaches the heat f

  47. C. A. Büsser, G. B. Martins, L. Costa Ribeiro, E. Vernek

    The spatial length of the Kondo screening is still a controversial issue related to Kondo physics. While renormalization group and Bethe Anzats solutions have provided detailed information about the thermodynamics of magnetic impurities, they are insufficient to study the effect on the surrounding electrons, i.e., the spatial range of the correlations create

  48. Stefania Fanali, Massimo Giulietti

    In this paper we solve three open problems on maximal curves with Frobenius dimension 3. In particular, we prove the existence of a maximal curve with order sequence (0,1,3,q).

  49. Olalla A. Castro-Alvaredo, Benjamin Doyon

    This manuscript is a review of the main results obtained in a series of papers involving the present authors and their collaborator J.L. Cardy over the last two years. In our work we have developed and applied a new approach for the computation of the bi-partite entanglement entropy in massive 1+1-dimensional quantum field theories. In most of our work we ha

  50. G. Chauvin, A. -M. Lagrange, M. Bonavita, B. Zuckerman

    Since November 2002, we have conducted the largest deep imaging survey of the young, nearby associations of the southern hemisphere. Our goal is detection and characterization of substellar companions at intermediate (10--500 AU) physical separations. We have observed a sample of 88 stars, mostly G to M dwarfs, that we essentially identify as younger than 10

  51. Stefania Fanali

    Some linear codes associated to maximal algebraic curves via Feng-Rao construction are investigated. In several case, these codes have better minimum distance with respect to the previously known linear codes with same length and dimension.

  52. Anton Baranov, Harald Woracek

    This is the second part in a series dealing with subspaces of de Branges spaces of entire function generated by majorization on subsets of the closed upper half-plane. In this part we investigate certain Banach spaces generated by admissible majorants. We study their interplay with the original de Branges space structure, and their geometry. In particular, w

  53. P. A. Ganai, J. A. Sheikh, I. Maqbool, R. P. Singh

    Temperature and angular momentum dependence of the quadrupole deformation is studied in the middle of the sd-shell for 28Si and 27Si isotopes using the spherical shell model approach. The shell model calculations have been performed using the standard USD interaction and the canonical partition function constructed from the calculated eigen-solutions. It is

  54. Noah J. Fitch, Carrie A. Weidner, L. Paul Parazzoli, H. R. Dullin

    The 1:1:2 resonant elastic pendulum is a simple classical system that displays the phenomenon known as Hamiltonian monodromy. With suitable initial conditions, the system oscillates between nearly pure springing and nearly pure elliptical-swinging motions, with sequential major axes displaying a stepwise precession. The physical consequence of monodromy is t

  55. U. Schwingenschlogl, I. A. Shelykh

    We consider the magnetic interaction of manganese phtalocyanine (MnPc) absorbed on Pb layers which were grown on a Si substrate. We perform an ab-initio calculation of the density of states and Kondo temperature as function of the number of Pb monolayers. Comparison to experimental data [Phys. Rev. Lett. 99, 256601 (2007)] then allows us to determine the exc

  56. Anton Baranov, Harald Woracek

    In this series of papers we study subspaces of de Branges spaces of entire functions which are generated by majorization on subsets $D$ of the closed upper half-plane. The present, first, part is addressed to the question which subspaces of a given de Branges space can be represented by means of majorization. Results depend on the set $D$ where majorization

  57. K. Holhjem, M. Schirmer, H. Dahle

    The aim of the present work is to study the overall mass distribution of the galaxy clusters Abell 1351 and Abell 1995 using weak gravitational lensing. These clusters have got a very different mass structure and dynamical state, and are the two extremes from a larger sample of 38 X-ray luminous clusters of similar size and redshift. We measure shear values

  58. Lorenzo Iorio

    In the framework of the MOdified Newtonian Dynamics (MOND), the internal dynamics of a gravitating system s embedded in a larger one S is affected by the external background field E of S even if it is constant and uniform, thus implying a violation of the Strong Equivalence Principle: it is the so-called External Field Effect (EFE). In the case of the solar

  59. Stefania Fanali, Massimo Giulietti

    Algebraic Geometric codes associated to a recently discovered class of maximal curves are investigated. As a result, some linear codes with better parameters with respect to the previously known ones are discovered, and 70 improvements on MinT&#39;s tables are obtained.

  60. Alberto G. Rojo, Anthony M. Bloch

    We consider the problem of a sphere rolling of a curved surface and solve it by mapping it to the precession of a spin 1/2 in a magnetic field of variable magnitude and direction. The mapping can be of pedagogical use in discussing both rolling and spin precession, and in particular in understanding the emergence of geometrical phases in classical problems.

  61. Patrick Popescu-Pampu

    Consider a smooth point O of a complex analytic surface S. A constellation based at O is a set of infinitely near points of O, centers of a sequence of blow-ups above O. Finite constellations are usually encoded in two ways: either using an Enriques diagram, or using the dual graph of the divisor obtained by blowing-up the points of the constellation. Both a

  62. Paula A. A. B. Carvalho, Christian Lomp, Dilek Pusat-Yilmaz

    The purpose of this paper is to study finiteness conditions on injective hulls of simple modules over Noetherian Down-Up algebras. We will show that the Noetherian Down-Up algebras A(α,β,γ) which are fully bounded are precisely those which are module-finite over a central subalgebra. We show that injective hulls of simple A(α,β,γ)-modules are locally Artinia

  63. Michael Keyl, Dirk-M. Schlingemann

    We present an approach to a non-commutative-like phase space which allows to analyze quasi-free states on the CAR algebra in analogy to quasi-free states on the CCR algebra. The used mathematical tools are based on a new algebraic structure the &#34;Grassmann algebra of canonical anti-commutation relations&#34; (GAR algebra) which is given by the twisted ten

  64. Mahmut Obol

    In this study, four different techniques are presented. 1 Rectangular waveguide measurement technique for normal microwave materials microwave properties such as permeability and permittivity. This technique removed guess parameter and dispersive effect issues of the old waveguide measurement techniques. It projects a new route for determination of any micro

  65. Laurent Busé, Guillaume Chèze, Salah Najib

    In this paper, the spectrum and the decomposability of a multivariate rational function are studied by means of the effective Noether&#39;s irreducibility theorem given by Ruppert. With this approach, some new effective results are obtained. In particular, we show that the reduction modulo p of the spectrum of a given integer multivariate rational function r

  66. Otfried Cheong, Xavier Goaoc, Andreas Holmsen

    A line L is a transversal to a family F of convex objects in R^d if it intersects every member of F. In this paper we show that for every integer d>2 there exists a family of 2d-1 pairwise disjoint unit balls in R^d with the property that every subfamily of size 2d-2 admits a transversal, yet any line misses at least one member of the family. This answers a

  67. Dominic C. Milioto

    In his paper &#34;On the Number of Primes Less Than a Given Magnitude&#34;, Bernhard Riemann introduced a prime counting function F(x) which counts the number of primes under x. Riemann obtained an analytic expression for F(x) by evaluating an inverse Laplace Transform. His method involved advanced techniques of analysis. However, this transform can be evalu

  68. Andras Nemethi, Patrick Popescu-Pampu

    The sandwiched surface singularities are those rational surface singularities which dominate birationally smooth surface singularities. de Jong and van Straten showed that one can reduce the study of the deformations of a sandwiched surface singularity to the study of deformations of a 1-dimensional object, a so-called decorated plane curve singularity. In p

  69. Piotr Bizon, Tadeusz Chmaj, Andrzej Rostworowski, Stanislaw Zajac

    We consider the late-time asymptotic behavior for solutions of Einstein&#39;s equations with the wave map matter. Solutions starting from small compactly supported $\ell$-equivariant initial data with $\ell\geq 1$ are shown to decay as $t^{-(2\ell+2)}$ at future timelike infinity and as $u^{-(\ell+1)}$ at future null infinity.

  70. Marco Fatuzzo, Fulvio Melia

    Molecular clouds at the Galactic center (GC) have environments considerably different from their disk counterparts. The GC may therefore provide important clues about how the environment affects star formation. Interestingly, while the inner 50 parsecs of our Galaxy include a remarkable population of high-mass stars, the initial mass function (IMF) appears t

  71. Cecile Appert-Rolland

    Single vehicle data obtained from magnetic loops on an expressway allowed us to measure velocity correlations and velocity differences between non--neighbor vehicles on the same lane, showing some strong correlations even for platoons of 7 or 8 vehicles. The corresponding time headway distribution for non--neighbor vehicles is also presented. We were also ab

  72. Ian D. Morris

    Using multiplicative ergodic theory we prove two formulae describing the relationships between different joint spectral radii for sets of bounded linear operators acting on a Banach space. In particular we recover a formula previously proved by V. S. Shulman and Yu. V. Turovski\uı using operator-theoretic ideas. As a byproduct of our method we answer a quest

  73. Mathieu Drouin, Laurent Gremillet, Jean-Claude Adam, Anne Héron

    Implicit particle-in-cell codes offer advantages over their explicit counterparts in that they suffer weaker stability constraints on the need to resolve the higher frequency modes of the system. This feature may prove particularly valuable for modeling the interaction of high-intensity laser pulses with overcritical plasmas, in the case where the electrosta

  74. Kari J. Eskola, Hannu Paukkunen, Carlos A. Salgado

    In this talk, we present our recent work on next-to-leading order (NLO) nuclear parton distribution functions (nPDFs), which we call EPS09. As an extension to earlier NLO analyses, we complement the deep inelastic scattering and Drell-Yan dilepton data by inclusive midrapidity pion production measurements from RHIC to reduce the otherwize large freedom of th

  75. M. Molina, L. Bassani, A. Malizia, J. B. Stephen

    In this paper we discuss the broad-band X-ray characteristics of a complete sample of 36 type 1 AGN, detected by INTEGRAL in the 20-40 keV band above the 5.5sigma level. We present, for all the objects in the sample, the broad-band (1-110 keV) spectral analysis obtained by using INTEGRAL/Swift-BAT observations together with XMM-Newton, Chandra, ASCA and Swif

  76. Sumiyoshi Abe

    A generalized definition of average, termed the q-average, is widely employed in the field of nonextensive statistical mechanics. Recently, it has however been pointed out that such an average value may behave unphysical under specific deformations of probability distributions. Here, the following three issues are discussed and clarified. Firstly, the deform

  77. A. V. Solov&#39;yov

    The main facts of the geometry of Finslerian 3-spinors are formulated. The close connection between Finslerian 3-spinors and vectors of the 9-dimensional linear Finslerian space is established. The isometry group of this space is described. The procedure of dimensional reduction to 4-dimensional quantities is formulated. The generalized Duffin-Kemmer equatio

  78. G. Van Hooydonk, Y. P. Varshni

    Symmetry breaking in Hsub2, quantified with Kratzer bond theory, leads to vibrational levels with errors of only 0,00008 %. For quanta, 0,0011 % errors are smaller than with any ab initio QM method. Chiral behavior of covalent bond Hsub2 implies bonding between left- and right-handed atoms HsubL and HsubR or between hydrogen H and antihydrogen Hbar. This gen

  79. Michel Rumin

    We prove some general Sobolev-type and related inequalities for positive operators A of given ultracontractive spectral decay, without assuming e^{-tA} is submarkovian. These inequalities hold on functions, or pure states, as usual, but also on mixed states, or density operators in the quantum mechanical sense. This provides universal bounds of Faber-Krahn t

  80. O. Jennrich

    This article reviews the present status of the technology and instrumentation for the joint ESA/NASA gravitational wave detector LISA. It briefly describes the measurement principle and the mission architecture including the resulting sensitivity before focussing on a description of the main payload items, such as the interferomtric measurement system, compr

  81. S. M. Kamil, A. K. Bhattacharjee, R. Adhikari, Gautam I. Menon

    We revisit the classic problem of the structure of the isotropic-nematic interface within Ginzburg-Landau-de Gennes theory, refining previous analytic treatments of biaxiality at the interface. We compare our analysis with numerical results obtained through a highly accurate spectral collocation scheme for the solution of the Landau-Ginzburg-de Gennes equati

  82. Gábor Simonyi, Gábor Tardos

    We investigate the local chromatic number of shift graphs and prove that it is close to their chromatic number. This implies that the gap between the directed local chromatic number of an oriented graph and the local chromatic number of the underlying undirected graph can be arbitrarily large. We also investigate the minimum possible directed local chromatic

  83. Aldo J. Lazar

    One shows that for two C^*-algebras A_1 and A_2 any continuous function on Prim(A_1)\times Prim(A_2) can be continuously extended to Prim(A_1\otimes A_2) provided it takes its values in a T_1 topological space. This generalizes a 1977 result of L.G. Brown. A new proof is given for a result of R.J. Archbold about the space of minimal primal ideals of A_1\otim

  84. S. Friedemann, N. Oeschler, C. Krellner, C. Geibel

    We report low-temperature measurements of the electrical resistivity of Yb(Rh1-xCox)2Si2 single crystals with 0 <= x <= 0.12. The isoelectronic substitution of Co on the Rh site leads to a decrease of the unit cell volume which stabilizes the antiferromagnetism. Consequently, the antiferromagnetic transition temperature increases upon Co substitution. For x

  85. J. L. Hernandez-Pastora

    The static solutions of the axially symmetric vacuum Einstein equations with a finite number of Relativistic Multipole Moments are described by means of a function that can be written in the same analytic form as the Newtonian gravitational multipole potential. A family of so-called MSA (Multipole-Symmetry Adapted) coordinates are introduced and calculated a

  86. Nick Halmagyi

    We study the first order form of the NS string sigma model allowing for worldsheet couplings corresponding on the target space to a bi-vector, a two-form and an inverse metric. Lifting the topological sector of this action to three dimensions produces several Wess-Zumino like terms which encode the bi-vector generalization of the Courant bracket. This bracke

  87. Alexandre Benoit, Bruno Salvy

    A Chebyshev expansion is a series in the basis of Chebyshev polynomials of the first kind. When such a series solves a linear differential equation, its coefficients satisfy a linear recurrence equation. We interpret this equation as the numerator of a fraction of linear recurrence operators. This interpretation lets us give a simple view of previous algorit

  88. Amine Bahayou, Mohamed Boucetta

    We study the triple $(G,π,\prs)$ where $G$ is a connected and simply connected Lie group, $π$ and $\prs$ are, respectively, a multiplicative Poisson tensor and a left invariant Riemannian metric on $G$ such that the necessary conditions, introduced by Hawkins, to the existence of a non commutative deformation (in the direction of $π$) of the spectrale triple

  89. Umberto Amato, Anestis Antoniadis, Alexander Samarov, Alexander Tsybakov

    We consider the problem of multivariate density estimation when the unknown density is assumed to follow a particular form of dimensionality reduction, a noisy independent factor analysis (IFA) model. In this model the data are generated by a number of latent independent components having unknown distributions and are observed in Gaussian noise. We do not as

  90. S. K. Boutle

    An overview of recent measurements of charm and beauty production in ep collisions at HERA is presented. Various techniques are used by the ZEUS and H1 collaborations to efficiently tag heavy quarks in events and different regions of phase space are explored. Differential cross sections are measured in both photoproduction and deep-inelastic scattering. The

  91. U. Reinosa, J. Serreau

    We discuss the formulation of the prototype gauge field theory, QED, in the context of two-particle-irreducible (2PI) functional techniques with particular emphasis on the issues of renormalization and gauge symmetry. We show how to renormalize all $n$-point vertex functions of the (gauge-fixed) theory at any approximation order in the 2PI loop-expansion by

  92. T. E. Cocolios, A. N. Andreyev, B. Bastin, N. Bree

    In-gas-cell laser spectroscopy study of the 57,59,63,65Cu isotopes has been performed for the first time using the 244.164 nm optical transition from the atomic ground state of copper. The nuclear magnetic dipole moments for 57,59,65Cu relative to that of 63Cu have been extracted. The new value for 57Cu of mu(57Cu) = +2.582(7)mu_N is in strong disagreement w

  93. Carlotta Giusti, Andrea Meucci, Franco Davide Pacati

    Relativistic models developed for the exclusive and inclusive QuasiElastic (QE) electron scattering have been extended to Charged-Current (CC) and Neutral-Current (NC) neutrino-nucleus scattering. The results of different descriptions of Final-State Interactions (FSI) are compared.

  94. Christian Villiers, Mireille Chevallet, Hélène Diemer, Rachel Couderc

    Dendritic cells are known to be activated by a wide range of microbial products, leading to cytokine production and increased levels of membrane markers such as major histocompatibility complex class II molecules. Such activated dendritic cells possess the capacity to activate naïve T cells. In the present study we demonstrated that immature dendritic cells

  95. M. Matsuura, A. K. Speck, B. M. McHunu, I. Tanaka

    We present a deep and wide field-of-view (4&#39;x 7&#39;) image of the planetary nebula (PN) NGC 7293 (the Helix Nebula) in the 2.12 micron H2 v=1-0 S(1) line. The excellent seeing (0.4&#39;&#39;) at the Subaru Telescope, allows the details of cometary knots to be examined. The knots are found at distances of 2.2&#39;-6.4&#39; from the central star (CS). At

  96. Robin Steinigeweg, Marcel Ogiewa, Jochen Gemmer

    We investigate the transport of a single excitation through a chain of weakly coupled subunits. At both ends the chain is exposed to baths which are incorporated by means of a master equation in Lindblad form. This master equation is solved by the use of stochastic unraveling in order to obtain excitation profile and current in the steady state. Completely d

  97. Pierre Hyvernat

    This short note contains random thoughts about a factorization theorem for closure/interior operators on a powerset which is reminiscent to the notion of resolution for a monad/comonad. The question originated from formal topology but is interesting in itself. The result holds constructively (even if it classically has several variations); but usually not pr

  98. Barco You

    Discuss several tricks for solving twenty question problems which in this paper is depicted as a guessing game. Player tries to find a ball in twenty boxes by asking as few questions as possible, and these questions are answered by only &#34;Yes&#34; or &#34;No&#34;. With the discussion, demonstration of source coding methods is the main concern.

  99. Lotfi Saidane

    Let $(E)$ a homogeneous linear differential equation of order $n$ Fuchsien over $\mathbb{P}^{1}(\mathbb{C}) $. The idea of Riemann (1857) was to obtain the properties of solutions of (E) by studying the local system. Thus, he obtained some properties of Gauss hypergeometric functions by studying the assocated rank 2 local system over $\mathbb{P}^{1}(\mathbb{

  100. Denis Benois

    In the previous paper we generalized Greenberg&#39;s construction of the $\Cal L$-invariant to semistable representations. Here we prove that this construction is compatible with Perrin-Riou&#39;s theory of $p$-adic $L$-functions