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January 2010 arXiv papers — page 13

Showing 1,2011,300 of 5,448 papers

  1. S. M. Hanasoge, T. L. Duvall, M. L. DeRosa

    We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by analyzing simulations of waves propagating through a velocity snapshot of global solar convection via methods of time-d

  2. Gastao S. F. Frederico, Delfim F. M. Torres

    We prove a Noether's theorem for fractional variational problems with Riesz-Caputo derivatives. Both Lagrangian and Hamiltonian formulations are obtained. Illustrative examples in the fractional context of the calculus of variations and optimal control are given.

  3. T. Fernandez-Carames, A. Valcarce, J. Vijande

    We present a systematic and selfconsistent analysis of four-quark charmonium states and applied it to study compact four-quark systems and meson-meson molecules. Our results are robust and should serve to clarify the situation of charmonium spectroscopy above the threshold production of charmed mesons.

  4. Enrico Carlini, Adam Van Tuyl

    Consider l lines in P^2 such that no three lines meet in a point. Let X(l) denote all points of intersections of these l lines. We describe all pairs (d,l) such that generic degree d curve in P^2 contains a X(l).

  5. G. De Cesare, P. Ubertini, A. Bazzano

    The IBIS imager on board the INTEGRAL satellite, thanks to the large field of view and good sensitivity, gave us a unique opportunity to search for possible 511 keV point sources either previously unknown or associated to known objects such as X-ray binaries or supernovae. The IBIS sensitivity at 511 keV depends on the gamma ray detector quantum efficiency a

  6. Jorge Penarrubia, Matthew G. Walker, Gerard Gilmore

    We use N-body simulations to study the tidal evolution of globular clusters (GCs) in dwarf spheroidal (dSph) galaxies. Our models adopt a cosmologically motivated scenario in which the dSph is approximated by a static NFW halo with a triaxial shape. For a large set of orbits and projection angles we examine the spatial and velocity distribution of stellar de

  7. Michal Nánási, Tomáš Vinař, Broňa Brejová

    Hidden Markov models are traditionally decoded by the Viterbi algorithm which finds the highest probability state path in the model. In recent years, several limitations of the Viterbi decoding have been demonstrated, and new algorithms have been developed to address them \citep{Kall2005,Brejova2007,Gross2007,Brown2010}. In this paper, we propose a new effic

  8. Kefeng Liu, Hao Xu

    We derive effective recursion formulae of top intersections in the tautological ring $R^*(M_g)$ of the moduli space of curves of genus $g\geq 2$. As an application, we prove a convolution-type tautological relation in $R^{g-2}(M_g)$.

  9. John M. Campbell, R. Keith Ellis, Ciaran Williams

    We perform an update of the next-to-leading order calculation of the rate for Higgs boson production in association with two jets. Our new calculation incorporates the full analytic result for the one-loop virtual amplitude. This new theoretical information allows us to construct a code including the decay of the Higgs boson without incurring a prohibitive p

  10. Florian Dorfler, Bruce Francis

    In the formation control problem for autonomous robots a distributed control law steers the robots to the desired target formation. A local stability result of the target formation can be derived by methods of linearization and center manifold theory or via a Lyapunov-based approach. It is well known that there are various other undesired invariant sets of t

  11. Josef Angermeier, Sandor P. Fekete, Tom Kamphans, Nils Schweer

    Every year, the computing resources available on dynamically partially reconfigurable devices increase enormously. In the near future, we expect many applications to run on a single reconfigurable device. In this paper, we present a concept for multitasking on dynamically partially reconfigurable systems called virtual area management. We explain its advanta

  12. M. El Beiyad, B. Pire, M. Segond, L. Szymanowski

    The chiral-odd transversity generalized parton distributions (GPDs) of the nucleon can be accessed experimentally through the exclusive photoproduction process gamma + N -> pi + rho + N', in the kinematics where the meson pair has a large invariant mass and the final nucleon has a small transverse momentum, provided the vector meson is produced in a tran

  13. Tao Huang Changyou Wang

    We establish both local and global well-posedness for the heat flow of polyharmonic maps from $R^n$ to a compact Riemannian manifold without boundary for initial data with small BMO norms.

  14. Jacco Th. van Loon, Joana M. Oliveira, Karl D. Gordon, G. C. Sloan

    We present 52-93 micron spectra, obtained with the Spitzer Space Telescope, of luminous compact far-IR sources in the SMC. These comprise 9 Young Stellar Objects (YSOs), the compact HII region N81 and a similar object within N84, and two red supergiants (RSGs). The spectra of the sources in N81 (of which we also show the ISO-LWS spectrum between 50-170 micro

  15. Wolfgang Ochs

    The scalar meson f_0(1370) - indicated in particular in the low energy p\bar p \to 3 body reactions - is a crucial element in certain schemes of the scalar meson spectroscopy including glueballs. The most definitive results can be obtained from elastic and inelastic pi pi phase shift analyses using the constraints from unitarity where the discrete ambiguitie

  16. D. Donatelli, S. Spirito

    In this paper we prove that weak solution constructed by artificial compressibility method are suitable in the sense of Scheffer. Using Hilbertian setting and Fourier transform with respect to the time we obtain nontrivial estimates of the pressure and the time derivate which allow us to pass into the limit.

  17. G. Lehaut, D. Durand, O. Lopez

    We show a systematic experimental study based on INDRA data of the stopping power in central symmetric nuclear reactions. Total mass of the systems goes from 80 to 400 nucleons while the incident energy range is from 12 AMeV to 100 AMeV. The role of isospin diffusion at 32 and 45 MeV/nucleon with 124,136Xe projectiles on 112,124Sn targets performed at GANIL

  18. S. G. Rohozinski, J. Dobaczewski, W. Nazarewicz

    Spatial symmetries of the densities appearing in the nuclear Density Functional Theory are discussed. General forms of the local densities are derived by using methods of construction of isotropic tensor fields. The spherical and axial cases are considered.

  19. K. A. Bugaev, P. T. Reuter

    We discuss exact analytical solutions of a variety of statistical models recently obtained for finite systems by a novel powerful mathematical method, the Laplace-Fourier transform. Among them are a constrained version of the statistical multifragmentation model, the Gas of Bags Model and the Hills and Dales Model of surface partition. Thus, the Laplace-Four

  20. J. M. Paredes, V. Zabalza

    The discovery of non-thermal X-ray emission from the jets of some X-ray binaries, and especially the discovery of GeV-TeV gamma-rays in some of them, provide a clear evidence of very efficient acceleration of particles to multi-TeV energies in these systems. The observations demonstrate the richness of non-thermal phenomena in compact galactic objects contai

  21. Ansgar Denner, Stefan Dittmaier, Thomas Gehrmann, Christian Kurz

    We report on a recent calculation of the electroweak O(α^3α_s) corrections to 3-jet production and related event-shape observables at e+e- colliders. The calculation properly accounts for the experimental photon isolation criteria and for the corrections to the total hadronic cross section. Corrections to the normalised event-shape distributions, which are e

  22. A. Rivera-Ingraham, M. H. van Kerkwijk

    We analyze the X-ray scattering halos around three Galactic Anomalous X-ray Pulsars (AXPs) in order to constrain the distance and the optical extinction of each source. We obtain surface brightness distributions from EPIC-pn data obtained with XMM-Newton, compare the profiles of different sources, and fit them with a model based on the standard theory of X-r

  23. Jeppe R. Andersen, Jennifer M. Smillie

    We discuss results from a recently proposed all-order description of hard, radiative corrections to certain multi-jet processes at hadron colliders. The description is based on obtaining an all-order estimate of the t-channel singularities of scattering amplitudes. As a simple example, we illustrate the similarities between qQ and qg-scattering. In particula

  24. Dionisis Stefanatos, Jr-Shin Li

    In this letter, we apply optimal control theory to design minimum-energy $π/2$ and $π$ pulses for the Bloch system in the presence of relaxation with constrained control amplitude. We consider a commonly encountered case in which the transverse relaxation rate is much larger than the longitudinal one so that the latter can be neglected. Using the Pontryagin&

  25. Alexandros Beskos, Natesh S. Pillai, Gareth O. Roberts, Jesus M. Sanz-Serna

    We investigate the properties of the Hybrid Monte-Carlo algorithm (HMC) in high dimensions. HMC develops a Markov chain reversible w.r.t. a given target distribution $Π$ by using separable Hamiltonian dynamics with potential $-\logΠ$. The additional momentum variables are chosen at random from the Boltzmann distribution and the continuous-time Hamiltonian dy

  26. Gerben Broenink, Jaap-Henk Hoepman, Christian van 't Hof, Rob van Kranenburg

    The Privacy Coach is an application running on a mobile phone that supports customers in making privacy decisions when confronted with RFID tags. The approach we take to increase customer privacy is a radical departure from the mainstream research efforts that focus on implementing privacy enhancing technologies on the RFID tags themselves. Instead the Priva

  27. Enrique Álvarez, Roberto Vidal

    Scale invariant (transverse) gravitational theories are introduced. They are invariant under pure metric rescalings (i.e. the matter fields are inert under those). This symmetry forbids the presence of a cosmological constant. Those theories are not invariant under the full set of diffeomorphisms, but only with respect to those locally characterized by the f

  28. Jérémie Chalopin, Victor Chepoi, Nicolas Nisse, Yann Vaxès

    In the classical cop and robber game, two players, the cop C and the robber R, move alternatively along edges of a finite graph G. The cop captures the robber if both players are on the same vertex at the same moment of time. A graph G is called cop win if the cop always captures the robber after a finite number of steps. Nowakowski, Winkler (1983) and Quill

  29. Wieb Bosma, Ionica Smeets

    We give an algorithm that finds a sequence of approximations with Dirichlet coefficients bounded by a constant only depending on the dimension. The algorithm uses the LLL-algorithm for lattice basis reduction. We present a version of the algorithm that runs in polynomial time of the input.

  30. M. E. Gusakov

    We study transport properties of a strongly interacting superfluid mixture of two Fermi-liquids. A typical example of such matter is the neutron-proton liquid in the cores of neutron stars. To describe the mixture, we employ the Landau theory of Fermi-liquids, generalized to allow for the effects of superfluidity. We formulate the kinetic equation and analyz

  31. Matthew W. Pennington, David K. Lubensky

    We examine a spatially discrete reaction diffusion model based on the interactions that create a periodic pattern in the Drosophila eye imaginal disc. This model is capable of generating a regular hexagonal pattern of gene expression behind a moving front, as observed in the fly system. In order to better understand the novel switch and template mechanism be

  32. E. A. Kochetov, V. A. Osipov

    A self-consisting gauge-theory approach to describe Dirac fermions on flexible surfaces with a disclination is formulated. The elastic surfaces are considered as embeddings into R^3 and a disclination is incorporated through a topologically nontrivial gauge field of the local SO(3) group which generates the metric with conical singularity. A smoothing of the

  33. D. Salart, O. Landry, N. Sangouard, N. Gisin

    Single-photon entanglement is a simple form of entanglement that exists between two spatial modes sharing a single photon. Despite its elementary form, it provides a resource as useful as polarization-entangled photons and it can be used for quantum teleportation and entanglement swapping operations. Here, we report the first experiment where single-photon e

  34. Dzmitry Badziahin, Jason Levesley, Sanju Velani

    Let $\mathcal{D}=(d_n)_{n=1}^\infty$ be a bounded sequence of integers with $d_n\ge 2$ and let $(i, j)$ be a pair of strictly positive numbers with $i+j=1$. We prove that the set of $x \in \RR$ for which there exists some constant $c(x) > 0$ such that \[ \max\{|q|_\DDD^{1/i}, \|qx\|^{1/j}\} > c(x)/ q \qquad \forall q \in \NN \] is one quarter winning (in the

  35. Michel Breger

    Amplitude and period variations have been detected in almost all types of pulsating stars. Many of these modulations are nearly periodic. In RR Lyrae stars the phenomenon in known as the Blazhko Effect. Because of the observed similarities, we propose to extend the definition to other groups. We illustrate the Blazhko Effect with examples from Cepheids, RR L

  36. M. Cignoni, M. Tosi, E. Sabbi, A. Nota

    We present a novel approach to derive the age of very young star clusters, by using the Turn-On (TOn). The TOn is the point in the color-magnitude diagram (CMD) where the pre-main sequence (PMS) joins the main sequence (MS). In the MS luminosity function (LF) of the cluster, the TOn is identified as a peak followed by a dip. We propose that by combining the

  37. Anton S. Galaev

    The holonomy algebra $\g$ of an $n+2$-dimensional Lorentzian manifold $(M,g)$ admitting a parallel distribution of isotropic lines is contained in the subalgebra $\simil(n)=(\Real\oplus\so(n))\zr\Real^n\subset\so(1,n+1)$. An important invariant of $\g$ is its $\so(n)$-projection $\h\subset\so(n)$, which is a Riemannian holonomy algebra. One component of the

  38. Y. I. Izotov, T. X. Thuan

    We present a new determination of the primordial helium mass fraction Yp, based on 93 spectra of 86 low-metallicity extragalactic HII regions, and taking into account the latest developments concerning systematic effects. These include collisional and fluorescent enhancements of HeI recombination lines, underlying HeI stellar absorption lines, collisional an

  39. Paolo Cea, Leonardo Cosmai, Massimo D'Elia, Chiara Manneschi

    We perform a numerical study of the systematic effects involved in the determination of the critical line at real baryon chemical potential by analytic continuation from results obtained at imaginary chemical potentials. We present results obtained in a theory free of the sign problem, three-color QCD with finite isospin chemical potential, and comment on ge

  40. Daniel Ventura, Mauricio Ayala-Rincón, Fairouz Kamareddine

    The lambda-calculus with de Bruijn indices assembles each alpha-class of lambda-terms in a unique term, using indices instead of variable names. Intersection types provide finitary type polymorphism and can characterise normalisable lambda-terms through the property that a term is normalisable if and only if it is typeable. To be closer to computations and t

  41. Bernhard Gramlich, Felix Schernhammer

    We propose a generalized version of context-sensitivity in term rewriting based on the notion of "forbidden patterns". The basic idea is that a rewrite step should be forbidden if the redex to be contracted has a certain shape and appears in a certain context. This shape and context is expressed through forbidden patterns. In particular we analyze th

  42. Ariel Gonzalez, Carlos Luna

    The study of variability in software development has become increasingly important in recent years. A common mechanism to represent the variability in a product line is by means of feature models. However, the relationship between these models and UML design models is not straightforward. UML statecharts are extended introducing variability in their main com

  43. Thomas Zaslavsky

    For each pair $(Q_i,Q_j)$ of reference points and each real number $r$ there is a unique hyperplane $h \perp Q_iQ_j$ such that $d(P,Q_i)^2 - d(P,Q_j)^2 = r$ for points $P$ in $h$. Take $n$ reference points in $d$-space and for each pair $(Q_i,Q_j)$ a finite set of real numbers. The corresponding perpendiculars form an arrangement of hyperplanes. We explore t

  44. Besik Dundua, Temur Kutsia, Mircea Marin

    PRholog is an experimental extension of logic programming with strategic conditional transformation rules, combining Prolog with Rholog calculus. The rules perform nondeterministic transformations on hedges. Queries may have several results that can be explored on backtracking. Strategies provide a control on rule applications in a declarative way. With stra

  45. Loet Leydesdorff, Peter Van den Besselaar

    A theory of citations should not consider cited and/or citing agents as its sole subject of study. One is able to study also the dynamics in the networks of communications. While communicating agents (e.g., authors, laboratories, journals) can be made comparable in terms of their publication and citation counts, one would expect the communication networks no

  46. Loet Leydesdorff, Peter Van den Besselaar

    Arthur's (1988) model for competing technologies is discussed from the perspective of evolution theory. Using Arthur's own model for the simulation, we show that 'lock-ins' can be suppressed by adding reflexivity or uncertainty on the side of consumers. Competing technologies then tend to remain in competition. From an evolutionary perspectiv

  47. Eduardo Bonelli, Pablo Barenbaum

    We study superdevelopments in the weak lambda calculus of Cagman and Hindley, a confluent variant of the standard weak lambda calculus in which reduction below lambdas is forbidden. In contrast to developments, a superdevelopment from a term M allows not only residuals of redexes in M to be reduced but also some newly created ones. In the lambda calculus the

  48. Tony Bourdier, Horatiu Cirstea, Daniel Dougherty, Hélène Kirchner

    This paper is a contribution to the theoretical foundations of strategies. We first present a general definition of abstract strategies which is extensional in the sense that a strategy is defined explicitly as a set of derivations of an abstract reduction system. We then move to a more intensional definition supporting the abstract view but more operational

  49. Sophie Dabo Niang, Baba Thiam

    In this paper, we present a statistical framework for modeling conditional quantiles of spatial processes assumed to be strongly mixing in space. We establish the $L_1$ consistency and the asymptotic normality of the kernel conditional quantile estimator in the case of random fields. We also define a nonparametric spatial predictor and illustrate the methodo

  50. Loet Leydesdorff, Nienke Oomes

    The emerging system at the European level can be conceptualized as a pattern of relations among member states that tends to be reproduced despite disturbances in individual trajectories. The Markov property is used as an indicator of systemness in the distribution. The individual trajectories of nations participating in the European Monetary System is assess

  51. Ali Mousavi, Pedram Pad, Farokh Marvasti

    Recently, a new class of binary codes for overloaded CDMA systems are proposed that not only has the ability of errorless communication but also suitable for detecting active users. These codes are called COWDA [1]. In [1], a Maximum Likelihood (ML) decoder is proposed for this class of codes. Although the proposed scheme of coding/decoding show impressive p

  52. Emerson Sadurni, Thomas Seligman, Fabrice Mortessagne

    The possibility of using hexagonal structures in general and graphene in particular to emulate the Dirac equation is the basis of our considerations. We show that Dirac oscillators with or without restmass can be emulated by distorting a tight binding model on a hexagonal structure. In a quest to make a toy model for such relativistic equations we first show

  53. Peter Johnson, Rachid Hourizi, Neil Carrigan, Nick Forbes

    In this paper we present an analysis of the complexities of large group collaboration and its application to develop detailed requirements for collaboration schema for Autonomous Systems (AS). These requirements flow from our development of a framework for collaboration that provides a basis for designing, supporting and managing complex collaborative system

  54. Riccardo Benedetti, Roberto Frigerio, Riccardo Ghiloni

    The goal of this paper is to describe and clarify as much as possible the 3-dimensional topology underlying the Helmholtz cuts method, which occurs in a wide theoretic and applied literature about Electromagnetism, Fluid dynamics and Elasticity on domains of the ordinary space. We consider two classes of bounded domains that satisfy mild boundary conditions

  55. Frank Bauer, Fatihcan M. Atay, Juergen Jost

    We study synchronization of non-diffusively coupled map networks with arbitrary network topologies, where the connections between different units are, in general, not symmetric and can carry both positive and negative weights. We show that, in contrast to diffusively coupled networks, the synchronous behavior of a non-diffusively coupled network can be drama

  56. E. Hernandez, J. Nieves, M. Valverde, M. J. Vicente-Vacas

    The N-Delta axial form factors are determined from neutrino induced pion production ANL & BNL data by using a state of the art theoretical model, which accounts both for background mechanisms and deuteron effects. We find violations of the off diagonal Goldberger-Treiman relation at the level of 2 sigma which might have an impact in background calculations f

  57. Laura Bocchi, José Fiadeiro, Noor Rajper, Stephan Reiff-Marganiec

    This paper provides an outline of a formal approach that we are developing for modelling Virtual Organisations (VOs) and their Breeding Environments (VBEs). We propose different levels of representation for the functional structures and processes that VBEs and VOs involve, which are independent of the specificities of the infrastructures (organisational and

  58. Vincent Tejedor, Olivier Benichou, Raphael Voituriez, Ralf Jungmann

    An increasing number of experimental studies employ single particle tracking to probe the physical environment in complex systems. We here propose and discuss new methods to analyze the time series of the particle traces, in particular, for subdiffusion phenomena. We discuss the statistical properties of mean maximal excursions, i.e., the maximal distance co

  59. Igor Mozolevsky, John Fitzgerald

    We propose a formal foundation for reasoning about access control policies within a Dynamic Coalition, defining an abstraction over existing access control models and providing mechanisms for translation of those models into information-flow domain. The abstracted information-flow domain model, called a Common Representation, can then be used for defining a

  60. J. Pospisil, M. Kratochvilova, J. Prokleska, M. Divis

    In this paper, specific features of Sm magnetism in an intermetallic compound have been studied. For this purpose, a high-quality single crystal of SmPd2Al3 was grown and subjected to detailed measurements of specific heat, magnetization, ac susceptibility, and electrical resistivity with respect to temperature and a magnetic field applied along the principa

  61. Ebru Devlen, E. Rennan Pekünlü

    We investigate the stability properties of a hot, dilute and differentially rotating weakly magnetized plasma which is believed to be found in the interstellar medium of galaxies and protogalaxies and in the low-density accretion flows around some giant black holes like the one in the Galactic center. In the linear MHD regime, we consider the combined effect

  62. E. Massaro, G. Ventura, F. Massa, M. Feroci

    GRS 1915+105 was observed by BeppoSAX for about 10 days in October 2000. For about 80% of the time, the source was in the variability class $ρ$, characterised by a series of recurrent bursts. We describe the results of the timing analysis performed on the MECS (1.6--10 keV) and PDS (15--100 keV) data. The X-ray count rate from \grss showed an increasing tren

  63. Jarred McGinnis, Kostas Stathis, Francesca Toni

    We propose a formal framework that supports a model of agent-based Virtual Organisations (VOs) for service grids and provides an associated operational model for the creation of VOs. The framework is intended to be used for describing different service grid applications based on multiple agents and, as a result, it abstracts away from any realisation choices

  64. Driss Bennis

    This paper unifies several generalizations of coherent rings in one notion. Namely, we introduce $n$-$\mathscr{X}$-coherent rings, where $\mathscr{X}$ is a class of modules and $n$ is a positive integer, as those rings for which the subclass $\mathscr{X}_n$ of $n$-presented modules of $\mathscr{X}$ is not empty, and every module in $\mathscr{X}_n$ is $n+1$-p

  65. Klara Uhlirova, Jan Prokleska, Vladimir Sechovsky, Stanislav Danis

    Solution growth of single crystals of the recently reported new compound Ce2PdIn8 was investigated. When growing from a stoichiometry in a range 2:1:20 - 2:1:35, single crystals of CeIn3 covered by a thin (~50 um) single-crystalline layer of Ce2PdIn8 were mostly obtained. Using palladium richer compositions the thickness of the Ce2PdIn8 layers were increased

  66. Mauro Carfora, Annalisa Marzuoli, Mario Rasetti

    We discuss in details the role of Wigner 6j symbol as the basic building block unifying such different fields as state sum models for quantum geometry, topological quantum field theory, statistical lattice models and quantum computing. The apparent twofold nature of the 6j symbol displayed in quantum field theory and quantum computing -a quantum tetrahedron

  67. C. S. Jeffery W. -R. Hamann

    Extreme helium stars are very rare low-mass supergiants in a late stage of evolution. They are probably contracting to become white dwarfs following a violent phase of evolution which caused them to become hydrogen-deficient giants, possibly R CrB stars. Using the latest generation of models for spherically expanding stellar atmospheres, we set out to measur

  68. A. Courvoisier, D. W. Hughes, M. R. E. Proctor

    The coupled equations that describe the effect of large-scale magnetic and velocity fields on forced high-diffusivity magnetohydrodynamic flows are investigated through an extension of mean field electrodynamics. Our results generalise those of Rädler & Brandenburg (2010), who consider a similar situation but assume that the effect of the Lorentz force on th

  69. K. Uhlirova, J. Prokleska, V. Sechovsky

    Comment to D. Kaczorowski et al., Phys. Rev. Lett. 103, 027003 (2009).

  70. Manabu Ozaki

    We will show that if $K$ is a knot of prime period $p>2$ and whose Alexander polynomial $Δ_K(t)$ is monic and of degree $p-1$, then $Δ_K(t)$ is uniquely determined only by $p$.

  71. Bjoern S. Schmekel

    Several Authors have demonstrated that substituting computer simulations for real experiments conducted in a lab may help to improve students' understanding of the material. In the present work we try to understand the reasons for this intriguing finding and investigate possible prerequisites necessary to achieve this outcome. The study was conducted in

  72. C. Lazarou, M. Keller, B. M. Garraway

    In this work we investigate the theory for three different uni-directional population transfer schemes in trapped multilevel systems which can be utilized to cool molecular ions. The approach we use exploits the laser-induced coupling between the internal and motional degrees of freedom so that the internal state of a molecule can be mapped onto the motion o

  73. Ben Burningham, S. K. Leggett, P. W. Lucas, D. J. Pinfield

    We report the discovery of a very cool d/sdL7+T7.5p common proper motion binary system, SDSS J1416+13AB, found by cross-matching the UKIDSS Large Area Survey Data Release 5 against the Sloan Digital Sky Survey Data Release 7. The d/sdL7 is blue in J-H and H-K and has other features suggestive of low-metallicity and/or high gravity. The T7.5p displays spectra

  74. Stefan Gerhold

    We investigate the number of sets of words that can be formed from a finite alphabet, counted by the total length of the words in the set. An explicit expression for the counting sequence is derived from the generating function, and asymptotics for large alphabet respectively large total word length are discussed. Moreover, we derive a Gaussian limit law for

  75. V. I. Yukalov

    Statistical systems, in which spontaneous symmetry breaking can be accompanied by spontaneous local symmetry restoration, are considered. A general approach to describing such systems is formulated, based on the notion of weighted Hilbert spaces and configuration averaging. The approach is illustrated by the example of a ferroelectric with mesoscopic fluctua

  76. P. Cea, L. Cosmai, M. D'Elia, A. Papa

    The method of analytic continuation is one of the most powerful tools to circumvent the sign problem in lattice QCD. The present study is part of a larger project which, based on the investigation of QCD-like theories which are free of the sign problem, is aimed at testing the validity of the method of analytic continuation and at improving its predictivity,

  77. I. C. Fulga, F. Hassler, C. W. J. Beenakker

    Electrical current fluctuations in a single-channel quantum point contact can produce photons (at frequency omega close to the applied voltage V x e/hbar) which inherit the sub-Poissonian statistics of the electrons. We extend the existing zero-temperature theory of the photostatistics to nonzero temperature T. The Fano factor F (the ratio of the variance an

  78. Igor A. Bandos

    We review the manifestation of the Brout-Englert-Higgs effect in general relativity interacting with point-like and extended objects (p-branes including string for p=1 and membrane for p=2), which manifests itself in the appearance of the brane source in the Einstein equation while the graviton remains massless (hep-th/0112207, hep-th/0507197 and refs therei

  79. Roger W. Anderson, Vincenzo Aquilanti, Annalisa Marzuoli

    Recoupling coefficients (3nj symbols) are unitary transformations between binary coupled eigenstates of N=(n+1) mutually commuting SU(2) angular momentum operators. They have been used in a variety of applications in spectroscopy, quantum chemistry and nuclear physics and quite recently also in quantum gravity and quantum computing. These coefficients, natur

  80. Wojciech Krolikowski

    In the case of previously proposed idea of photonic portal to hidden sector, the parity in this sector may be violated. We discuss here two new options within our model, where the parity is preserved. The first of them is not satisfactory, as not diplaying a full relativistic covariance. The second seems to be satisfactory.

  81. S. Rozov, E. Armengaud, C. Augier, L. Bergé

    This paper describes precise measurements of the thermal neutron flux in the LSM underground laboratory in proximity of the EDELWEISS-II dark matter search experiment together with short measurements at various other locations. Monitoring of the flux of thermal neutrons is accomplished using a mobile detection system with low background proportional counter

  82. Hans Zantema, Matthias Raffelsieper

    Streams are infinite sequences over a given data type. A stream specification is a set of equations intended to define a stream. A core property is productivity: unfolding the equations produces the intended stream in the limit. In this paper we show that productivity is equivalent to termination with respect to the balanced outermost strategy of a TRS obtai

  83. Lidia Obojska

    We propose a Relational Calculus based on the concept of unary relation. In this Relational Calculus different axiomatic systems converge to a model called Dynamic Generative System with Symmetry (DGSS). In DGSS we define the concepts of relational set and function and prove that extensionality and the substitution property of equality are theorems of DGSS.

  84. A. R. King, J. E. Pringle

    The nearest accretion disc to us in space if not time was the protosolar nebula. Remnants of this nebula thus potentially offer unique insight into how discs work. In particular the existence of chondrules, which must have formed in the disc as small molten droplets, requires strong and intermittent heating of disc material. We argue that this places importa

  85. Vibhor Singh, Shamashis Sengupta, Hari S. Solanki, Rohan Dhall

    We use suspended graphene electromechanical resonators to study the variation of resonant frequency as a function of temperature. Measuring the change in frequency resulting from a change in tension, from 300 K to 30 K, allows us to extract information about the thermal expansion of monolayer graphene as a function of temperature, which is critical for strai

  86. B. G. Konopelchenko, G. Ortenzi

    A class of Hamiltonian deformations of plane curves is defined and studied. Hamiltonian deformations of conics and cubics are considered as illustrative examples. These deformations are described by systems of hydrodynamical type equations. It is shown that solutions of these systems describe processes of formation of singularities (cusps, nodes), bubbles, a

  87. E. Spitoni, F. Calura, F. Matteucci, S. Recchi

    The existence of a mass-metallicity (MZ) relation in star forming galaxies at all redshift has been recently established. We aim at studying some possible physical mechanisms contributing to the MZ relation by adopting analytical solutions of chemical evolution models including infall and outflow. We explore the hypotheses of a variable galactic wind rate, i

  88. Igor Aharonovich, Stefania Castelletto, Brett C. Johnson, Jeffrey C. McCallum

    Controlled fabrication and identification of bright single photon emitters is at the heart of quantum optics and materials science. Here we demonstrate a controlled engineering of a chromium bright single photon source in bulk diamond by ion implantation. The Cr center has fully polarized emission with a ZPL centered at 749 nm, FWHM of 4 nm, an extremely sho

  89. G. A. Steele, A. K. Huettel, B. Witkamp, M. Poot

    Nanoscale resonators that oscillate at high frequencies are useful in many measurement applications. We studied a high-quality mechanical resonator made from a suspended carbon nanotube driven into motion by applying a periodic radio frequency potential using a nearby antenna. Single-electron charge fluctuations created periodic modulations of the mechanical

  90. K. M. Dasyra, B. M. Peterson, L. J. Tacconi, H. Netzer

    We present results from infrared spectroscopic projects that aim to test the relation between the mass of a black hole, M_BH, and the velocity dispersion of the stars in its host-galaxy bulge. We demonstrate that near-infrared, high-resolution spectroscopy assisted by adaptive optics is key in populating the high-luminosity end of the relation. We show that

  91. Natalia Zorii

    The study deals with a minimal energy problem over noncompact classes of infinite dimensional vector measures in a locally compact space. The components are positive measures (charges) satisfying certain normalizing assumptions and supported by given closed sets (plates) with the sign +1 or -1 prescribed such that oppositely signed sets are mutually disjoint

  92. Iina Hellsten, James Dawson, Loet Leydesdorff

    The framing of issues in the mass media plays a crucial role in the public understanding of science and technology. This article contributes to research concerned with diachronic analysis of media frames by making an analytical distinction between implicit and explicit media frames, and by introducing an automated method for analysing diachronic changes of i

  93. Ben Craps

    Despite impressive phenomenological successes, cosmological models are incomplete without an understanding of what happened at the big bang singularity. Depending on the model, one would like to understand how appropriate initial conditions were selected at the big bang singularity, or how a pre-existing contracting universe underwent a big crunch/big bang t

  94. Victor Guerrero, Ronald B. Morgan, Walter Wilcox

    We propose a new noise subtraction method, which we call "eigenspectrum subtraction", which uses low eigenmode information to suppress statistical noise at low quark mass. This is useful for lattice calculations involving disconnected loops or all-to-all propagators. It has significant advantages over perturbative subtraction methods. We compare unsu

  95. S. Bravyi, M. B. Hastings

    Recently, the stability of certain topological phases of matter under weak perturbations was proven. Here, we present a short, alternate proof of the same result. We consider models of topological quantum order for which the unperturbed Hamiltonian $H_0$ can be written as a sum of local pairwise commuting projectors on a $D$-dimensional lattice. We consider

  96. V. Beckmann, C. Ricci, S. Soldi, J. Alfonso-Garzon

    The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows to test the unified scheme for AGN. We present results based on the analysis of 199 AGN. A difference between the Seyfert types is detected in slightly flatter spectra with higher cut-off energies and lower luminosities for the more absorbed/type 2 AGN. Wh

  97. Ming Ding, Fan Xu

    We define an analogue of the Caldero-Chapoton map (\cite{CC}) for the cluster category of finite dimensional nilpotent representations over a cyclic quiver. We prove that it is a cluster character (in the sense of \cite{Palu}) and satisfies some inductive formulas for the multiplication between the generalized cluster variables (the images of objects of the

  98. I. Kraus, J. Cleymans, H. Oeschler, K. Redlich

    Prospects for strangeness production in pp collisions at the Large Hadron Collider (LHC) are discussed within the statistical model. Firstly, the system size and the energy dependence of the model parameters are extracted from existing data and extrapolated to LHC energy. Particular attention is paid to demonstrate that the chemical decoupling temperature is

  99. Pietro Govoni, Chiara Mariotti

    The production of Z bosons via Vector Boson Fusion at the LHC collider at 10 TeV centre-of-mass energy has been studied. The aim is to investigate the possibility to isolate a known Standard Model process to be used as reference for the measurement of the detector performance for the search of the Higgs Boson produced via Vector Boson Fusion. The signal to b

  100. Alexander Belavin, Chaiho Rim

    We consider bulk correlation numbers on disk in one-matrix model. Using the recently found so-called resonance transformation from the KdV to the Liouville frame, we obtain an explicit expression for the bulk one-point function. The result is consistent with the form of FZZ one-point function in the boundary Liouville Field Theory.