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October 2010 arXiv papers — page 64

Showing 6,3016,400 of 6,460 papers

  1. Wesam Gabran, Przemysław Pawełczak, Danijela Čabrić

    Multi-stage sensing is a novel concept that refers to a general class of spectrum sensing algorithms that divide the sensing process into a number of sequential stages. The number of sensing stages and the sensing technique per stage can be used to optimize performance with respect to secondary user throughput and the collision probability between primary an

  2. Benjamin Dodson

    In this paper we prove that the defocusing, quintic nonlinear Schrödinger initial value problem is globally well-posed and scattering for $u_{0} \in L^{2}(\mathbf{R})$. To do this, we will prove a frequency localized interaction Morawetz estimate similar to the estimate made in [11]. Since we are considering an $L^{2}$ - critical initial value problem we wil

  3. Shu-Wei Chen, Ching-Chang Lin, Kwei-Chou Yang

    We calculate the $S$-wave charmonium spectroscopy using the Hamiltonian with the non-relativistic QCD (NRQCD) potential. The logarithmic factor $\ln μr$, appearing in the next-to-leading order QCD loop corrections to the potential, is expanded about $r=1/μ$, where $μ$ corresponds to the typical charmonium scale. The resulting potential characterized by the C

  4. Suresh Kumar

    The paper deals with a spatially homogeneous and isotropic FRW space-time filled with perfect fluid and dark energy components. The two sources are assumed to interact minimally, and therefore their energy momentum tensors are conserved separately. A special law of variation for the Hubble parameter proposed by Berman (1983) has been utilized to solve the fi

  5. Keith Stroyan

    Researchers especially beginning with (Rogers & Graham, 1982) have noticed important psychophysical and experimental similarities between the neurologically different motion parallax and stereopsis cues. Their quantitative analysis relied primarily on the "disparity equivalence" approximation. In this article we show that retinal motion from lateral

  6. Boris Gutkin

    For a bounded planar domain $Ω^0$ whose boundary contains a number of flat pieces $Γ_i$ we consider a family of non-symmetric billiards $Ω$ constructed by patching several copies of $Ω^0$ along $Γ_i$'s. It is demonstrated that the length spectrum of the periodic orbits in $Ω$ is degenerate with the multiplicities determined by a matrix group $G$. We stud

  7. Hiroyuki Kamano

    We present the current status of a combined and simultaneous analysis of meson production reactions based on a dynamical coupled-channels (DCC) model, which is conducted at Excited Baryon Analysis Center (EBAC) of Jefferson Lab.

  8. Juan A. Bazerque, Gonzalo Mateos, Georgios B. Giannakis

    The unceasing demand for continuous situational awareness calls for innovative and large-scale signal processing algorithms, complemented by collaborative and adaptive sensing platforms to accomplish the objectives of layered sensing and control. Towards this goal, the present paper develops a spline-based approach to field estimation, which relies on a basi

  9. Matti Jarvinen

    Several phenomenologically viable walking technicolor models have been proposed recently. I demonstrate that these models can have first order electroweak phase transitions, which are sufficiently strong for electroweak baryogenesis. Strong dynamics can also lead to several separate transitions at the electroweak scale, with the possibility of a temporary re

  10. B. Ruiz-Granados, J. A. Rubino-Martin, E. Florido, E. Battaner

    Recent observations of the rotation curve of M31 show a rise of the outer part that can not be understood in terms of standard dark matter models or perturbations of the galactic disc by M31's satellites. Here, we propose an explanation of this dynamical feature based on the influence of the magnetic field within the thin disc. We have considered standar

  11. Kirill A. Velizhanin, Andrei Piryatinski

    Using previously developed exciton scattering model accounting for the interband, i.e., exciton-biexciton, Coulomb interactions in semiconductor nanocrystals (NCs), we derive a closed set of equations for 2D double-quantum coherence signal. The signal depends on the Liouville space pathways which include both the interband scattering processes and the inter-

  12. Liliya L. R. Williams, Jens Hjorth, Radoslaw Wojtak

    We compare the DARKexp differential energy distribution, N(E) \propto \exp(ϕ_0-E)-1, obtained from statistical mechanical considerations, to the results of N-body simulations of dark matter halos. We first demonstrate that if DARKexp halos had anisotropic velocity distributions similar to those of N-body simulated halos, their density and energy distribution

  13. Liliya L. R. Williams, Jens Hjorth

    In this paper, we present the density, ρ, velocity dispersion, σ, and ρ/σ^3 profiles of isotropic systems which have the energy distribution, N(E)\propto[\exp(ϕ_0-E)-1], derived in Paper I. This distribution, dubbed DARKexp, is the most probable final state of a collisionless self-gravitating system, which is relaxed in terms of particle energies, but not ne

  14. Jens Hjorth, Liliya L. R. Williams

    We present an equilibrium statistical mechanical theory of collisionless self-gravitational systems with isotropic velocity distributions. Compared to existing standard theories, we introduce two changes: (1) the number of possible microstates is computed in energy (orbit) space rather than phase space and (2) low occupation numbers are treated more appropri

  15. Oleg Kochukhov

    The upper main sequence magnetic chemically peculiar (Ap) stars exhibit a non-uniform distribution of chemical elements across their surfaces and with height in their atmospheres. These inhomogeneities, responsible for the conspicuous photometric and spectroscopic variation of Ap stars, are believed to be produced by atomic diffusion operating in the stellar

  16. Hechang Lei, Rongwei Hu, E. S. Choi, C. Petrovic

    Thermally activated flux flow (TAFF) and flux flow Hall effect (FFHE) of Fe(Te,S) single crystal in the mixed state are studied in magnetic fields up to 35 T. Thermally activated energy (TAE) is analyzed using conventional Arrhenius relation and modified TAFF theory which is closer to experimental results. The results indicate that there is a crossover from

  17. Peter A. Sturrock, Luca Bertello

    This article presents a power-spectrum analysis of 39,024 measurements of the solar diameter made at the Mount Wilson Observatory from 1968.670 to 1997.965. This power spectrum contains a number of very strong peaks. We find that eight of these peaks agree closely with the frequencies of r-mode oscillations for a region of the Sun where the sidereal rotation

  18. Ilka Agricola, Julia Becker-Bender, Thomas Friedrich

    Consider the nonstandard embedding of SO(3) into SO(5) given by the 5-dimensional irreducible representation of SO(3), henceforth called SO(3)_\ir. In this note, we study the topology and the differential geometry of 5-dimensional Riemannian manifolds carrying such an SO(3)_\ir structure, i.\,e. with a reduction of the frame bundle to SO(3)_\ir.

  19. O. A. Croze, E. E. Ashraf, M. A. Bees

    The recent interest in using microorganisms for biofuels is motivation enough to study bioconvection and cell dispersion in tubes subject to imposed flow. To optimize light and nutrient uptake, many microorganisms swim in directions biased by environmental cues (e.g. phototaxis in algae and chemotaxis in bacteria). Such taxes inevitably lead to accumulations

  20. Timothy Cohen, Henriette Elvang, Michael Kiermaier

    We study "on-shell constructibility" of tree amplitudes from recursion relations in general 4-dimensional local field theories with any type of particles, both massless and massive. Our analysis applies to renormalizable as well as non-renormalizable interactions, with or without supersymmetry. We focus on recursion relations that arise from complex

  21. Andrew Lutomirski

    Wiesner's quantum money [5] is a simple, information-theoretically secure quantum cryptographic protocol. In his protocol, a mint issues quantum bills and anyone can query the mint to authenticate a bill. If the mint returns bogus bills when it is asked to authenticate them, then the protocol can be broken in linear time.

  22. Lara B. Anderson, James Gray, Andre Lukas, Burt Ovrut

    In this paper, we show that the presence of gauge fields in heterotic Calabi-Yau compacitifications causes the stabilisation of some, or all, of the complex structure moduli of the Calabi-Yau manifold while maintaining a Minkowski vacuum. Certain deformations of the Calabi-Yau complex structure, with all other moduli held fixed, can lead to the gauge bundle

  23. J. H. Nam, H. S. Kim, A. J. Hatt, N. A. Spaldin

    The recent discovery of a stress-induced structural phase transition in the single-component perovskite BiFeO3 has revived interest in this lead-free ferroelectric. The coexistence of different phases may lead to large piezoelectric coefficients, a property typically associated with complex solid solutions of lead-based perovskites. Here we report combined e

  24. M. Akbari-Moghanjoughi

    Using the extended Poincaré-Lighthill-Kuo (PLK) reductive perturbation method to study the small-amplitude ion acoustic solitary wave (IASW) dynamics (propagation and interaction), it is shown that in Thomas-Fermi magneto-plasma consisting of inertial-less degenerate electrons and positrons and isothermal ions, distinctive features emerge when the ultra-rela

  25. Marc Kamionkowski, Tristan L. Smith, Alan Heavens

    Minimum-variance estimators for the parameter fnl that quantifies local-model non-Gaussianity can be constructed from the cosmic microwave background (CMB) bispectrum (three-point function) and also from the trispectrum (four-point function). Some have suggested that a comparison between the estimates for the values of fnl from the bispectrum and trispectrum

  26. Aaron T. Lee, Eugene Chiang, Xylar Asay-Davis, Joe Barranco

    Dust at the midplane of a circumstellar disk can become gravitationally unstable and fragment into planetesimals if the local dust-to-gas density ratio mu is sufficiently high. We simulate how dust settles in passive disks and ask how high mu can become. We settle the dust using a 1D code and test for dynamical stability using a 3D shearing box code. This sc

  27. Aaron T. Lee, Eugene Chiang, Xylar Asay-Davis, Joseph Barranco

    Gravitational instability (GI) of a dust-rich layer at the midplane of a gaseous circumstellar disk is one proposed mechanism to form planetesimals, the building blocks of rocky planets and gas giant cores. Self-gravity competes against the Kelvin-Helmholtz instability (KHI): gradients in dust content drive a vertical shear which risks overturning the dusty

  28. Crystal Brasseur, Peter B. Stetson, Don A. VandenBerg, Luca Casagrande

    We have obtained broad-band near-infrared photometry for seven Galactic star clusters (M92, M15, M13, M5, NGC1851, M71 and NGC6791) using the WIRCam wide-field imager on the Canada-France-Hawaii Telescope, supplemented by images of NGC1851 taken with HAWK-I on the VLT. In addition, 2MASS observations of the [Fe/H] ~ 0.0 open cluster M67 were added to the clu

  29. Lawrence J. Hall, John March-Russell, Stephen M. West

    We propose a unified theory of dark matter (DM) genesis and baryogenesis. It explains the observed link between the DM density and the baryon density, and is fully testable by a combination of collider experiments and precision tests. Our theory utilises the "thermal freeze-in" mechanism of DM production, generating particle anti-particle asymmetries

  30. Paul McFadden, Kostas Skenderis

    We discuss the phenomenology of recently proposed holographic models of inflation, in which the very early universe is non-geometric and is described by a dual three-dimensional quantum field theory (QFT). We analyze models determined by a specific class of dual QFTs and show that they have the following universal properties: (i) they have a nearly scale inv

  31. M. Cattani

    In this article we analyze the predictions of the Einstein gravitation theory (EGT) on black holes in the framework of the Schwarzschild geometry that is defined in the vacuum around a spherically symmetric mass distribution, without charge, not in rotation. The Eddington and Kruskal metrics have been also taken unto account and the topological connections n

  32. Wang-Kong Tse, A. H. MacDonald

    We develop a theory of the magneto-optical and magneto-electric properties of a topological insulator thin film in the presence of a quantizing external magnetic field. We find that low-frequency magneto-optical properties depend only on the sum of top and bottom surface Dirac-cone filling factors $ν_{\mathrm{T}}$ and $ν_{\mathrm{B}}$, whereas the low-freque

  33. Claude LeBrun

    Let (M,h) be a compact 4-dimensional Einstein manifold, and suppose that h is Hermitian with respect to some complex structure J on M. Then either (M,J,h) is Kaehler-Einstein, or else, up to rescaling and isometry, it is one of the following two exceptions: the Page metric on CP2 # (-CP2), or the Einstein metric on CP2 # 2 (-CP2) constructed in Chen-LeBrun-W

  34. Kristina Lerman, Tad Hogg

    Popularity of content in social media is unequally distributed, with some items receiving a disproportionate share of attention from users. Predicting which newly-submitted items will become popular is critically important for both hosts of social media content and its consumers. Accurate and timely prediction would enable hosts to maximize revenue through d

  35. Rolf Kuiper, Hubert Klahr, Henrik Beuther, Thomas Henning

    We present radiation hydrodynamics simulations of the collapse of massive pre-stellar cores. We treat frequency dependent radiative feedback from stellar evolution and accretion luminosity at a numerical resolution down to 1.27 AU. In the 2D approximation of axially symmetric simulations, it is possible for the first time to simulate the whole accretion phas

  36. Francis Halzen

    Despite their discovery potential touching a wide range of science, construction of TeV gamma-ray telescopes, Auger, IceCube and a suite of other particle astrophysics experiments has been largely motivated by the hunt for the sources of cosmic rays. I will assess the status of our search for the still-enigmatic sources of cosmic rays. Although a resolution

  37. Greg Maloney, Aaron Tikuisis

    This paper systematically studies finite rank dimension groups, as well as finite dimensional ordered real vector spaces with Riesz interpolation. We provide an explicit description and classification of finite rank dimension groups, in the following sense. We show that for each n, there are (up to isomorphism) finitely many ordered real vector spaces of dim

  38. Denjoe O'Connor, J. A. Santiago, C. R. Stephens, A. Zamora

    Using Environmentally Friendly Renormalization, we present an analytic calculation of the series for the renormalization constants that describe the equation of state for the $O(N)$ model in the whole critical region. The solution of the beta-function equation, for the running coupling to order two loops, exhibits crossover between the strong coupling fixed

  39. I. F. Rúa, Elías F. Combarro, J. Ranilla

    Finite nonassociative division algebras (i.e., finite semifields) with 243 elements are completely classified.

  40. J. Brian Pitts

    Both particle physics and the 1890s Seeliger-Neumann modification of Newtonian gravity suggest considering a "mass term" for gravity, yielding a finite range due to an exponentially decaying Yukawa potential. Unlike Nordström's "massless" theory, massive scalar gravities are strictly Special Relativistic, being invariant under the Poincar

  41. Lalitha Sankar, S. Raj Rajagopalan, H. Vincent Poor

    Ensuring the usefulness of electronic data sources while providing necessary privacy guarantees is an important unsolved problem. This problem drives the need for an overarching analytical framework that can quantify the safety of personally identifiable information (privacy) while still providing a quantifable benefit (utility) to multiple legitimate inform

  42. P. Roig

    We analyze the hadronization structure of $τ\to ηπ^- π^0 ν_τ$ decays. In the isospin limit only the vector current contributes to this process. We compute the relevant form factor within Resonance Chiral Theory, at leading order in the $1/N_C$ expansion, and considering only the contribution of the lightest vector resonances. The couplings in the resonance t

  43. S. X. Nakamura

    We address a question about how much resonance poles and residues extracted from data depend on a model used for the extraction, and on the precision of data. We focus on the P11 pi-N scattering and use the dynamical coupled-channel (DCC) model developed in Excited Baryon Analysis Center (EBAC) at JLab. We examine the model-dependence of the poles by varying

  44. E. Alec Johnson, James A. Rossmanith

    For the first time to our knowledge, we demonstrate fast magnetic reconnection near a magnetic null point in a fluid model of collisionless pair plasma without resorting to the contrivance of anomalous resistivity. In particular, we demonstrate that fast reconnection occurs in an anisotropic adiabatic two-fluid model of collisionless pair plasma with relaxat

  45. Arnab Kar, S. G. Rajeev

    We propose classical equations of motion for a charged particle with magnetic moment, taking radiation reaction into account. This generalizes the Landau-Lifshitz equations for the spinless case. In the special case of spin-polarized motion in a constant magnetic field (synchrotron motion) we verify that the particle does lose energy. Previous proposals did

  46. A. Sanna, F. Bernardini, G. Profeta, S. Sharma

    We report on theoretical calculations of the optical conductivity of Ba [Fe(1-x)Co(x)]2 As2, as obtained from density functional theory within the full potential LAPW method. A thorough comparison with experiment shows that we are able to reproduce most of the observed experimental features, in particular a magnetic peak located at about 0.2 eV which we ascr

  47. Anthony Labarre, Josef Cibulka

    Pancake flipping, a famous open problem in computer science, can be formalised as the problem of sorting a permutation of positive integers using as few prefix reversals as possible. In that context, a prefix reversal of length k reverses the order of the first k elements of the permutation. The burnt variant of pancake flipping involves permutations of sign

  48. Jörn Warnecke, Axel Brandenburg

    Magnetic buoyancy is believed to drive the transport of magnetic flux tubes from the convection zone to the surface of the Sun. The magnetic fields form twisted loop-like structures in the solar atmosphere. In this paper we use helical forcing to produce a large-scale dynamo-generated magnetic field, which rises even without magnetic buoyancy. A two layer sy

  49. Wenwu Tian, Denis Leahy

    We briefly summarize recent results of five TeV SNRs from radio and X-ray observations. We focus on remeasuring kinematic distances of 5 TeV SNRs, i.e. HESS J1732-347/SNR G353.6-0.7 (3.2 kpc), HESS J1834-087/G23.3-0.3 (also W41, 4.0 kpc), HESS J1833-105/G21.5-0.9 (4.8 kpc), HESS J1846-029/G29.7-0.3 (Kes 75, 6.3 kpc) and TeV SNR G54.1-0.3 (6.5 kpc), and study

  50. Z. -C. Liang, L. Gizon, H. Schunker

    We observe and characterize the scattering of acoustic wave packets by a sunspot, in a regime where the wavelength is comparable to the size of the sunspot. Spatial maps of wave traveltimes and amplitudes are measured from the cross-covariance function of the random wave field. The averaging procedure is such that incoming wave packets are plane wave packets

  51. M. De La Sen

    This paper is concerned with the investigation of the controllability and observability of Caputo fractional differential linear systems of any real order α . Expressions for the expansions of the evolution operators in powers of the matrix of dynamics are first obtained. Sets of linearly independent continuous functions or matrix functions, which are also C

  52. S. S. Chabysheva

    A nonperturbative method for the solution of quantum field theories is described in the context of quantum electrodynamics and applied to the calculation of the electron's anomalous magnetic moment. The method is based on light-front quantization and Pauli-Villars regularization. The application to light-front QED is intended as a test of the methods in

  53. Piotr T. Chruściel, Sebastian J. Szybka

    We show stable causality of the Pomeransky-Senkov black rings.

  54. Anastasia Korshunova, Olga Rozanova

    We extend our result of [1] and show that one can associate with the stochastically perturbed non-viscid Burgers equation a system of viscous balance laws. The Cauchy data for the Burgers equation generates the data for this system. Till the moment of the shock formation in the solution to the Burgers equation the above system of viscous balance laws can be

  55. Stephane Collion

    We study in this work the existence of minimizing solutions to the critical-power type equation $\triangle_{\textbf{g}}u+h.u = f.u^{\frac{n+2}{n-2}}$ on a compact riemannian manifold in the limit case normally not solved by variational methods. For this purpose, we use a concept of "critical function" that was originally introduced by E. Hebey and M.

  56. Fabio Bagarello, Francesco Oliveri

    We adopt the so--called \emph{occupation number representation}, originally used in quantum mechanics and recently considered in the description of stock markets, in the analysis of the dynamics of love relations. We start with a simple model, involving two actors (Alice and Bob): in the linear case we obtain periodic dynamics, whereas in the nonlinear regim

  57. Nigel Hitchin

    On a generalized complex manifold there is an associated definition of a generalized holomorphic bundle, introduced by Gualtieri. This notion in the case of an ordinary complex structure yields an object which we call a co-Higgs bundle and we consider the B-field action of a closed form of type (1,1), both local and global. The effect makes contact with both

  58. G. Eichmann, R. Alkofer, C. S. Fischer, A. Krassnigg

    We examine the nucleon's electromagnetic form factors in a Poincare-covariant Faddeev framework. The three-quark core contributions to the form factors are obtained by employing a quark-diquark approximation. We implement the self-consistent solution for the quark-photon vertex from its inhomogeneous Bethe-Salpeter equation. We find that the resulting tr

  59. Rieuwert J. Blok, Bruce N. Cooperstein

    We prove that the Grassmannian of totally isotropic $k$-spaces of the polar space associated to the unitary group $\mathsf{SU}_{2n}(\mathbb{F})$ ($n\in \mathbb{N}$) has generating rank ${2n\choose k}$ when $\mathbb{F}\ne \mathbb{F}_4$. We also reprove the main result of Blok [Blok2007], namely that the Grassmannian of totally isotropic $k$-spaces associated

  60. Fabio Bagarello

    We construct a two-parameters example of {\em pseudo-bosons}, and we show that they are not regular, in the sense previously introduced by the author. In particular, we show that two biorthogonal bases of $\Lc^2(\Bbb R)$ can be constructed, which are not Riesz bases, in general.

  61. C. Aubin, K. Orginos

    We discuss a new approach to reducing excited state contributions from two- and three-point correlation functions in lattice simulations. For the purposes of this talk, we focus on the Delta(1232) resonance and discuss how this new method reduces excited state contamination from two-point functions and mention how this will be applied to three-point function

  62. Rieuwert J. Blok, Bruce N. Cooperstein

    In this short note, completing a sequence of studies by Cooperstein, Kasikova and Shult, we consider the k-Grassmannians of a number of polar geometries of finite rank n. We classify those subspaces that are isomorphic to the j-Grassmannian of a projective m-space. In almost all cases, these are parabolic, that is, they are the residues of a flag of the pola

  63. S. S. Chabysheva

    The methods of light-front quantization and Pauli-Villars regularization are applied to a nonperturbative calculation of the dressed-electron state in quantum electrodynamics. This is intended as a test of the methods in a gauge theory, as a precursor to possible methods for the nonperturbative solution of quantum chromodynamics. The electron state is trunca

  64. Paul R. Archer

    In order to investigate the phenomenological implications of allowing gauge fields to propagate in warped spaces of more than five dimensions, we consider a toy model of a space warped by the presence of a anisotropic bulk cosmological constant. After solving the Einstein equation, three classes of solutions are found, those in which the additional ($D>5$) d

  65. T. Sako

    The LHC forward experiment (LHCf) is specifically designed for measurements of the very forward ($η$$>$8.4) production cross sections of neutral pions and neutrons at Large Hadron Collider (LHC) at CERN. LHCf started data taking in December 2009, when the LHC started to provide stable collisions of protons at $\sqrt{s}$=900\,GeV. Since March 2010, LHC increa

  66. Ion Patrascu, Florentin Smarandache

    In this article we'll present an elementary proof of a theorem of Alexandru Pantazi (1896-1948), Romanian mathematician, regarding the bi-orthological triangles.

  67. J. C. Phillips

    At vertical edges, thin films of silicon oxide (SiO_{2-x}) contain semiconductive c-Si layered nanocrystals (Si NC) embedded in and supported by an insulating g-SiO2 matrix. Tour et al. have shown that a trenched thin film geometry enables the NC to form switchable nanowires (SNW) when trained by an applied field. The field required to form SNW decreases rap

  68. Shane A. Maloney, Peter T. Gallagher

    Coronal mass ejections (CMEs) are large-scale ejections of plasma and magnetic field from the solar corona, which propagate through interplanetary space at velocities of $\sim$100--2500~km~s$^{-1}$. Although plane-of-sky coronagraph measurements have provided some insight into their kinematics near the Sun ($<$32~R$_\odot$), it is still unclear what forces g

  69. K. V. Belyakov, V. F. Suleimanov, E. A. Nikolaeva, N. V. Borisov

    The spectral energy distribution (SED) of the TT Ari system, which is well known from published IUE and optical photometric observations, was modeled by a steady-state accretion α-disc around a white dwarf. Parameters of the system were derived from time-resolved optical spectral observations in the bright state that we obtained in Sep. 1998. The radial velo

  70. David Geist, Seiichiro Ii, Koichi Tsuchiya, Hans-Peter Karnthaler

    The intermetallic compound Zr3Al is severely deformed by the method of repeated cold rolling. By X-ray diffraction it is shown that this leads to amorphization. TEM investigations reveal that a homogeneously distributed debris of very small nanocrystals is present in the amorphous matrix that is not resolved by X-ray diffraction. After heating to 773 K, the

  71. Nam Yul Yu

    Reed-Muller codes are studied for peak power control in multicarrier code-division multiple access (MC-CDMA) communication systems. In a coded MC-CDMA system, the information data multiplexed from users is encoded by a Reed-Muller subcode and the codeword is fully-loaded to Walsh-Hadamard spreading sequences. The polynomial representation of a coded MC-CDMA

  72. D. G. Yakin, V. F. Suleimanov, V. V. Shimansky, N. V. Borisov

    Results of photometric and spectroscopic investigations of the recently discovered disc cataclysmic variable star 1RXS J180834.7+101041 are presented. Emission spectra of the system show broad double peaked hydrogen and helium emission lines. Doppler maps for the hydrogen lines demonstrate strongly non-uniform emissivity distribution in the disc, similar to

  73. J. J. Heremans, L. L. Xu

    It is shown that an Aharonov-Casher vector potential in a two-dimensional geometry can lead to helical edge states. The Aharonov-Casher vector potential is the electromagnetic dual of the magnetic vector potential, and leads to traveling states at the sample edge in analogy to the integer quantum Hall effect. The helical edge states are predicted to appear i

  74. Beenish Anam, Kazi Sakib, Md. Alamgir Hossain, Keshav Dahal

    Since security is one of the most important issues, the evolve of cryptography and cryptographic analysis are considered as the fields of on-going research. The latest development on this field is DNA cryptography. It has emerged after the disclosure of computational ability of Deoxyribo Nucleic Acid (DNA). DNA cryptography uses DNA as the computational tool

  75. Ahmed Bouziad, Jean-Pierre Troallic

    Let $X$ and $Y$ be topological spaces, let $Z$ be a metric space, and let $f: X\times Y\to Z$ be a mapping. It is shown that when $Y$ has a countable base $\mathcal B$, then under a rather general condition on the set-valued mappings $X\ni x\to f_x(B)\in 2^Z$, $B\in\mathcal B$, there is a residual set $R\subset X$ such that for every $(a,b)\in R\times Y$, $f

  76. Vegard Lima, N. Lovasoa Randrianarivony

    In 1999, Bates, Johnson, Lindenstrauss, Preiss and Schechtman asked whether a Banach space that is a uniform quotient of $\ell_p$, $1 < p \neq 2 < \infty$, must be isomorphic to a linear quotient of $\ell_p$. We apply the geometric property $(β)$ of Rolewicz to the study of uniform and Lipschitz quotient maps, and answer the above question positively for the

  77. Yiwei Song, Natasha Devroye

    We demonstrate a decoding scheme for nested lattice codes which is able to decode a list of a particular size which contains the transmitted codeword with high probability. This list decoder is analogous to that used in random coding arguments in achievability schemes of relay channels, and allows for the effective combination of information from the relay a

  78. F. Bouchy, M. Deleuil, T. Guillot, S. Aigrain

    We report the discovery by the CoRoT space mission of a transiting brown dwarf orbiting a F7V star with an orbital period of 3.06 days. CoRoT-15b has a radius of 1.12 +0.30 -0.15 Rjup, a mass of 63.3 +- 4.1 Mjup, and is thus the second transiting companion lying in the theoretical mass domain of brown dwarfs. CoRoT-15b is either very young or inflated compar

  79. Thorsten Holm, Alexander Zimmermann

    Bialkowski, Erdmann and Skowronski classified those indecomposable self-injective algebras for which the Nakayama shift of every (non-projective) simple module is isomorphic to its third syzygy. It turned out that these are precisely the deformations, in a suitable sense, of preprojective algebras associated to the simply laced ADE Dynkin diagrams and of ano

  80. K. Yamada, S. Inaba

    We study Type I migration of a planet in a radiatively efficient disk using global two dimensional hydrodynamic simulations. The large positive corotation torque is exerted on a planet by an adiabatic disk at early times when the disk has the steep negative entropy gradient. The gas on the horseshoe orbit of the planet is compressed adiabatically during the

  81. V. I. Dokuchaev, S. V. Chernov

    We have calculated a discrete spectrum and found an exact analytical solution in the form of Meixner polynomials for the wave function of a thin gravitating shell in the Reissner-Nordstrom geometry. We show that there is no extreme state in the quantum spectrum of the gravitating shell, as in the case of extreme black hole.

  82. Elena Accomando, Stefania De Curtis, Daniele Dominici, Luca Fedeli

    We study the phenomenology of the neutral gauge sector of the four-site Higgsless model, based on the SU(2)_L x SU(2)_1 x SU(2)_2 x U(1)_Y gauge symmetry, at present colliders. The model predicts the existence of two neutral and four charged extra gauge bosons, Z_{1,2} and W^\pm_{1,2}. We expand and update a previous study, by concentrating on the neutral se

  83. Massoud Masoumi

    Developed by Paul Kocher, Joshua Jaffe, and Benjamin Jun in 1999, Differential Power Analysis (DPA) represents a unique and powerful cryptanalysis technique. Insight into the encryption and decryption behavior of a cryptographic device can be determined by examining its electrical power signature. This paper describes a novel approach for implementation of t

  84. Mohammad Momani, Subhash Challa

    This paper introduces the security and trust concepts in wireless sensor networks and explains the difference between them, stating that even though both terms are used interchangeably when defining a secure system, they are not the same. The difference between reputation and trust is also explained, highlighting that reputation partially affects trust. A su

  85. A. N. Poddubny, A. A. Prokofiev, I. N. Yassievich

    Dynamics of hot carriers confined in Si nanocrystals is studied theoretically using atomistic tight binding approach. Radiative, Auger-like and phonon-assisted processes are considered. The Auger-like energy exchange between electrons and holes is found to be the fastest process in the system. However the energy relaxation of hot electron-hole pair is govern

  86. Herwig Hauser, Josef Schicho

    We propose a combinatorial game on finite graphs, called Salmagundy, that is played by two protagonists, Dido and Mephisto. The game captures the logical structure of a proof of the resolution of singularities. In each round, the graph of the game is modified by the moves of the players. When it assumes a final configuration, Dido has won. Otherwise, the gam

  87. Arnulf Jentzen, Peter Kloeden

    The solution of a parabolic stochastic partial differential equation (SPDE) driven by an infinite-dimensional Brownian motion is in general not a semi-martingale anymore and does in general not satisfy an Itô formula like the solution of a finite-dimensional stochastic ordinary differential equation (SODE). In particular, it is not possible to derive stochas

  88. D. Colferai, F. Schwennsen, L. Szymanowski, S. Wallon

    For the first time, a next-to-leading BFKL study of the cross section and azimuthal decorrellation of Mueller Navelet jets is performed, i.e. including next-to-leading corrections to the Green&#39;s function as well as next-to-leading corrections to the Mueller Navelet vertices. The obtained results for standard observables proposed for studies of Mueller Na

  89. Marco Roncaglia, Cristian Degli Esposti Boschi, Arianna Montorsi

    The repulsive one-dimensional Hubbard model with bond-charge interaction (HBC) in the superconducting regime is mapped onto the spin-1/2 XY model with transverse field. We calculate correlations and phase boundaries, realizing an excellent agreement with numerical results. The critical line for the superconducting transition is shown to coincide with the ana

  90. Mubasher Jamil

    Motivated by several observational and theoretical developments concerning the variability of Newton&#39;s gravitational constant with time $G(t)$, we calculate the varying $G$ correction to the statefinder parameters for four models of dark energy namely interacting dark energy, holographic dark energy, new-agegraphic dark energy and generalized Chaplygin g

  91. Gerald Paul

    For almost two decades the question of whether tabu search (TS) or simulated annealing (SA) performs better for the quadratic assignment problem has been unresolved. To answer this question satisfactorily, we compare performance at various values of targeted solution quality, running each heuristic at its optimal number of iterations for each target. We find

  92. Andreas Schmidt Jensen

    Whereas classical multi-agent systems have the agent in center, there have recently been a development towards focusing more on the organization of the system. This allows the designer to focus on what the system goals are, without considering how the goals should be fulfilled. This paper investigates whether taking this approach has any clear advantages to

  93. Roberto A. Lineros

    Recent observations of lepton cosmic rays, coming from the PAMELA and FERMI experiments, have pushed our understanding of the interstellar medium and cosmic rays sources to unprecedented levels. The imprint of dark matter on lepton cosmic rays is the most exciting explanation of both PAMELA&#39;s positron excess and FERMI&#39;s total flux of electrons. Alter

  94. V. Suleimanov, J. Poutanen, M. Revnivtsev, K. Werner

    We present an extended set of model atmospheres and emergent spectra of X-ray bursting neutron stars in low mass X-ray binaries. Compton scattering is taken into account. The models were computed in LTE approximation for six different chemical compositions: pure hydrogen and pure helium atmospheres, and atmospheres with a solar mix of hydrogen and helium and

  95. Andreas Schmidt Jensen

    Since many of the currently available multi-agent frameworks are generally mostly intended for research, it can be difficult to built multi-agent systems using physical robots. In this report I describe a way to combine the multi-agent framework Jason, an extended version of the agent-oriented programming language AgentSpeak, with Lego robots to address this

  96. Federico Corberi, Leticia F. Cugliandolo, Hajime Yoshino

    We summarize studies of growing lengths in different aging systems. The article is structured as follows. We recall the definition of a number of observables, typically correlations and susceptibilities, that give access to dynamic and static correlation lengths. We use a growing length perspective to review three out of equilibrium cases: domain growth phen

  97. Yu. V. Churkin, A. B. Fedortsov, G. L. Klimchitskaya, V. A. Yurova

    The van der Waals and Casimir-Polder interaction of different atoms with graphene is investigated using the Dirac model which assumes that the energy of quasiparticles is linear with respect to the momentum. The obtained results for the van der Waals coefficients of hydrogen atoms and molecules and atoms of metastable He${}^{\ast}$ and Na as a function of se

  98. Claudia Köhler

    We classify the thick subcategories of an algebraic triangulated standard category with finitely many indecomposable objects.

  99. Jørgen Villadsen, Niklas Skamriis Boss, Andreas Schmidt Jensen, Steen Vester

    We provide a brief description of the Jason-DTU system, including the methodology, the tools and the team strategy that we plan to use in the agent contest.

  100. G. V. Efimov

    Bound state problem in the relativistic QED is investigated by the functional integral methods. The ortho- para- positron mass difference is calculated. Contribution of the &#34;nonphysical&#34;$~$ time variable turned out to be important and leads to the nonanalytic dependence of the bound state mass of the order $α^{2\over3}$. It is shown that the relativi