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April 2010 arXiv papers — page 48

Showing 4,7014,800 of 5,597 papers

  1. Miao Li, Yi Pang

    We show that to accommodate inflation in the entropic force scenario of Verlinde, it is necessary to introduce a negative temperature on a holographic screen, this will introduce several puzzles such as energy non-conservation. If one tries to modify the derivation of the Einstein equations to avoid a negative temperature, we prove that it is impossible to f

  2. Jun Gao, Chong Sheng Li, Bo Hua Li, C. -P. Yuan

    We present a complete next-to-leading order (NLO) QCD calculation to a heavy resonance production and decay into a top quark pair at the LHC, where the resonance could be either a Randall-Sundrum (RS) Kaluza-Klein (KK) graviton $G$ or an extra gauge boson $Z'$. The complete NLO QCD corrections can enhance the total cross sections by about $80\%- 100\%$ a

  3. Stefan Jansen, Nikolai Neumaier, Gregor Schaumann, Stefan Waldmann

    In this paper we investigate equivariant Morita theory for algebras with momentum maps and compute the equivariant Picard groupoid in terms of the Picard groupoid explicitly. We consider three types of Morita theory: ring-theoretic equivalence, *-equivalence and strong equivalence. Then we apply these general considerations to star product algebras over symp

  4. Jonathan Spreer

    We investigate slicings of combinatorial manifolds as properly embedded co-dimension 1 submanifolds. A focus is given to dimension 3 where slicings are normal surfaces. In the case of 2-neighborly 3-manifolds and quadrangulated slicings, a lower bound on the number of quadrilaterals of normal surfaces depending on the genus g is presented. It is shown to be

  5. Lin Lin, Joseph Morrone, Roberto Car, Michele Parrinello

    The proton momentum distribution, accessible by deep inelastic neutron scattering, is a very sensitive probe of the potential of mean force experienced by the protons in hydrogen-bonded systems. In this work we introduce a novel estimator for the end to end distribution of the Feynman paths, i.e. the Fourier transform of the momentum distribution. In this fo

  6. S. R. Clark, A. J. Connor, D. Jaksch, S. Popescu

    Relativistic causality has dramatic consequences on the measurability of nonlocal variables and poses the fundamental question of whether it is physically meaningful to speak about the value of nonlocal variables at a particular time. Recent work has shown that by weakening the role of the measurement in preparing eigenstates of the variable it is in fact po

  7. Laszlo Erdos

    We study the universality of spectral statistics of large random matrices. We consider $N\times N$ symmetric, hermitian or quaternion self-dual random matrices with independent, identically distributed entries (Wigner matrices) where the probability distribution for each matrix element is given by a measure $ν$ with a subexponential decay. Our main result is

  8. Benjamin Golub, Yair Livne

    This paper develops strategic foundations for an important statistical model of random networks with heterogeneous expected degrees. Based on this, we show how social networking services that subtly alter the costs and indirect benefits of relationships can cause large changes in behavior and welfare. In the model, agents who value friends and friends of fri

  9. Joe Silk, Adi Nusser

    Force balance considerations put a limit on the rate of AGN radiation momentum output, $L/c$, capable of driving galactic superwinds and reproducing the observed $\mbh -σ$ relation between black hole mass and spheroid velocity dispersion. We show that black holes cannot supply enough momentum in radiation to drive the gas out by pressure alone. Energy-driven

  10. E. Brian Davies, Pavel Exner, Jiri Lipovsky

    Inspired by a recent result of Davies and Pushnitski, we study resonance asymptotics of quantum graphs with general coupling conditions at the vertices. We derive a criterion for the asymptotics to be of a non-Weyl character. We show that for balanced vertices with permutation-invariant couplings the asymptotics is non-Weyl only in case of Kirchhoff or anti-

  11. Cihangir Ozemir, Faruk Gungor

    We apply Painlevé test to the most general variable coefficient nonlinear Schrodinger (VCNLS) equations as an attempt to identify integrable classes and compare our results versus those obtained by the use of other tools like group-theoretical approach and the Lax pairs technique of the soliton theory. We present explicit transformation formulae that can be

  12. E. Del Monte, M. Feroci, Y. Evangelista, E. Costa

    We present the observation of Cyg X-1 in hard spectral state performed during the AGILE Science Verification Phase and Observing Cycle 1 in hard X-rays (with SuperAGILE) and gamma rays (with the GRID) and lasting for about 160 days with a live time of $\sim 6$ Ms. We investigate the variability of Cyg X-1 in hard X-rays at different timescales, from $\sim 30

  13. Taras Verkholyak, Jozef Strecka, Michal Jascur, Johannes Richter

    The Jordan-Wigner transformation is applied to study magnetic properties of the quantum spin-1/2 $XX$ model on the diamond chain. Generally, the Hamiltonian of this quantum spin system can be represented in terms of spinless fermions in the presence of a gauge field and different gauge-invariant ways of assigning the spin-fermion transformation are considere

  14. Sung-Chul Yoon, Stan E. Woosley, Norbert Langer

    We investigate the evolution of Type Ib/c supernova (SN Ib/c) progenitors in close binary systems, using new evolutionary models that include the effects of rotation, with initial masses of 12 - 25 Msun for the primary components, and of single helium stars with initial masses of 2.8 - 20 Msun. We find that, despite the impact of tidal interaction on the rot

  15. Swarup Kumar Majee, Narendra Sahu

    We explore the discovery potential of doubly charged Higgs bosons (ξ^{\pm\pm}) at the CERN Large Hadron Collider (LHC). For moderate values of the coupling constants in the original Type-II seesaw model, these doubly-charged Higgs bosons are not accessible by any present or near future collider experiments. In a gauged B-L symmetric model we introduce two tr

  16. Tristram Bogart, Raymond Hemmecke, Sonja Petrović

    Associated to any vector configuration A is a toric ideal encoded by vectors in the kernel of A. Each toric ideal has two special generating sets: the universal Gröbner basis and the Graver basis. While the former is generally a proper subset of the latter, there are cases for which the two sets coincide. The most prominent examples among them are toric idea

  17. Laurent Bienvenu, Frank Stephan, Jason Teutsch

    In the theory of algorithmic randomness, one of the central notions is that of computable randomness. An infinite binary sequence X is computably random if no recursive martingale (strategy) can win an infinite amount of money by betting on the values of the bits of X. In the classical model, the martingales considered are real-valued, that is, the bets made

  18. Miroslav Bulíček, Mohamed Majdoub, Josef Málek

    In order to describe behavior of various liquid-like materials at high pressures, incompressible fluid models with pressure dependent viscosity seem to be a suitable choice. In the context of implicit constitutive relations involving the Cauchy stress and the velocity gradient these models are consistent with standard procedures of continuum mechanics. Under

  19. Pierre-Guy Plamondon

    We apply our previous work on cluster characters for Hom-infinite cluster categories to the theory of cluster algebras. We give a new proof of Conjectures 5.4, 6.13, 7.2, 7.10 and 7.12 of Fomin and Zelevinsky's Cluster algebras IV for skew-symmetric cluster algebras. We also construct an explicit bijection sending certain objects of the cluster category

  20. Walter Smilga

    The S matrix of e--e scattering has the structure of a projection operator that projects incoming separable product states onto entangled two-electron states. In this projection operator the empirical value of the fine-structure constant alpha acts as a normalization factor. When the structure of the two-particle state space is known, a theoretical value of

  21. A. Kovács, A. Omont, A. Beelen, C. Lonsdale

    We present SHARC-2 350 micron data on 20 luminous z ~ 2 starbursts with S(1.2mm) > 2 mJy from the Spitzer-selected samples of Lonsdale et al. and Fiolet et al. All the sources were detected, with S(350um) > 25 mJy for 18 of them. With the data, we determine precise dust temperatures and luminosities for these galaxies using both single-temperature fits and m

  22. Dmytro Gavinsky, Alexander A. Sherstov

    We prove that NP differs from coNP and coNP is not a subset of MA in the number-on-forehead model of multiparty communication complexity for up to k = (1-\epsilon)log(n) players, where \epsilon>0 is any constant. Specifically, we construct a function F with co-nondeterministic complexity O(log(n)) and Merlin-Arthur complexity n^{\Omega(1)}. The problem was o

  23. Daniel Gayo-Avello

    Micro-blogging services such as Twitter allow anyone to publish anything, anytime. Needless to say, many of the available contents can be diminished as babble or spam. However, given the number and diversity of users, some valuable pieces of information should arise from the stream of tweets. Thus, such services can develop into valuable sources of up-to-dat

  24. Jakob Bohr, Kasper Olsen

    We describe a geometrical property of helical structures and show how it accounts for the early art of ropemaking. Helices have a maximum number of rotations that can be added to them -- and it is shown that this is a geometrical feature, not a material property. This geometrical insight explains why nearly identically appearing ropes can be made from very d

  25. Maknickas Algirdas Antano

    With applying of new proposed electromagnetic gravity Lagrangian together with Einstein-Hilbert equation not zero space curvature was derived. The curvature gives "a priory" postulate of equivalence of mass and electromagnetic field gravity properties. The non zero trace of energy-stress tensor of electrical field changes space curvature of gravity mass, whi

  26. Qing-Guo Huang

    We calculate the trispectrum in ghost inflation where both the contact diagram and scale-exchange diagram are taken into account. The shape of trispectrum is discussed carefully and we find that the local form is absent in ghost inflation. In general, for the non-local shape trispectrum there are not analogous parameters to $τ_{NL}^{loc.}$ and $g_{NL}^{loc.}

  27. Stefan Nimmrichter, Klemens Hammerer, Peter Asenbaum, Helmut Ritsch

    We derive a master equation for the motion of a polarizable particle weakly interacting with one or several strongly pumped cavity modes. We focus here on massive particles with complex internal structure such as large molecules and clusters, for which we assume a linear scalar polarizability mediating the particle-light interaction. The predicted friction a

  28. Aleksey V. Belyaev, Olga I. Vinogradova

    Patterned surfaces with large effective slip lengths, such as super-hydrophobic surfaces containing trapped gas bubbles, have the potential to reduce hydrodynamic drag. Based on lubrication theory, we analyze an approach of a hydrophilic disk to such a surface. The drag force is predicted analytically and formulated in terms of a correction function to the R

  29. Zhuo Li, Xiao-Hong Zhao

    Long-lived >100 MeV emission has been a common feature of most Fermi-LAT detected gamma-ray bursts (GRBs), e.g., detected up to ~10^3s in long GRBs 080916C and 090902B and ~10^2s in short GRB 090510. This emission is consistent with being produced by synchrotron emission of electrons accelerated to high energy by the relativistic collisionless shock propagat

  30. T. Kiesel, W. Vogel

    Necessary and sufficient conditions for the nonclassicality of bosonic quantum states are formulated by introducing nonclassicality filters and nonclassicality quasiprobability distributions. Regular quasiprobabilities are constructed from characteristic functions which can be directly sampled by balanced homodyne detection. Their negativities uncover the no

  31. Soroush Akhlaghi, Abbas Kiani, Mohammad Reza Ghanavati

    Distributed storage systems are mainly justified due to the limited amount of storage capacity and improving the reliability through distributing data over multiple storage nodes. On the other hand, it may happen the data is stored in unreliable nodes, while it is desired the end user to have a reliable access to the stored data. So, in an event that a node

  32. Yves Auffray, Pierre Barbillon, Jean-Michel Marin

    In the paradigm of computer experiments, the choice of an experimental design is an important issue. When no information is available about the black-box function to be approximated, an exploratory design have to be used. In this context, two dispersion criteria are usually considered: the minimax and the maximin ones. In the case of a hypercube domain, a st

  33. A. S. Bakry, D. B. Leinweber, P. J. Moran, A. Sternbeck

    The distribution of the gluon action density in mesonic systems is investigated at finite temperature. The simulations are performed in quenched QCD for two temperatures below the deconfinment phase. Unlike the gluonic profiles displayed at T=0, the action density iso-surfaces display a prolate-spheroid like shape. The curved width profile of the flux-tube i

  34. M. J. Biercuk, H. Uys, J. W. Britton, A. P. VanDevender

    The ability to detect extremely small forces is vital for a variety of disciplines including precision spin-resonance imaging, microscopy, and tests of fundamental physical phenomena. Current force-detection sensitivity limits have surpassed 1 $aN/\sqrt{Hz}$ (atto $=10^{-18}$) through coupling of micro or nanofabricated mechanical resonators to a variety of

  35. Shahram Biglari

    The additivity of traces in certain tensor triangulated categories for endomorphisms of finite order of distinguished triangles is investigated. For the identity endomorphism this has been fully established by J. P. May ("The additivity of traces in triangulated categories", Adv. Math., 2001, 163, 34-73). By imposing extra conditions on the coefficie

  36. Kamaljit Lakhtaria, Bhaskar N. Patel, Satish G. Prajapati, N. N. Jani

    This article has been withdrawn by arXiv admins because it contains plagiarized content from International Conference on Computer Networks and Security (ICCNS 2008, September 27-28, 2008): "Securing AODV for MANETs using Message Digest with Secret Key", by Sunil J. Soni and Prashant B. Swadas.

  37. Mladen Pavicic, Brendan D. McKay, Norman D. Megill, Kresimir Fresl

    Using a graph approach to quantum systems, we prove that descriptions of 3-dim Kochen-Specker (KS) setups as well as descriptions of 3-dim spin systems by means of Greechie lattices that we find in the literature are wrong. Correct lattices generated by McKay-Megill-Pavicic (MMP) hypergraphs and Hilbert subspace equations are given. To enable exhaustive gene

  38. Roberto A. Sussman, German Izquierdo

    We consider spherically symmetric inhomogeneous dust models with a positive cosmological constant, $Λ$, given by the Lemaitre-Tolman-Bondi metric. These configurations provide a simple but useful generalization of the Lambda-CDM model describing cold dark matter (CDM) and a Lambda term, which seems to fit current cosmological observations. The dynamics of th

  39. Doan The Hieu

    Hyperplanes, hyperspheres and hypercylinders in $\Bbb R^n$ with suitable densities are proved to be weighted minimizing by a calibration argument. Also calibration method is used to prove a weighted minimal hypersurface is weighted area-minimizing locally.

  40. Leticia Carigi, Manuel Peimbert

    We present chemical evolution models of the Galactic disk with different Z-dependent yields. We find that a moderate mass loss rate for massive stars of solar metallicity produces an excellent fit to the observed C/H and C/O gradients of the Galactic disk. The best model also fits: the H, He, C, and O abundances derived from recombination lines of M17, the p

  41. Itzhak Bars, Shih-Hung Chen

    Exact analytic solutions for a class of scalar-tensor gravity theories with a hyperbolic scalar potential are presented. Using an exact solution we have successfully constructed a model of inflation that produces the spectral index, the running of the spectral index and the amplitude of scalar perturbations within the constraints given by the WMAP 7 years da

  42. Ryuichi Shindou, Akira Furusaki, Naoto Nagaosa

    We show that Majorana edge modes of two-dimensional spin-triplet topological superconductors have Ising-like spin density whose direction is determined by the d-vector characterizing the spin-triplet pairing symmetry. Exchange coupling between an impurity spin (S=1/2) and Majorana edge modes is thus Ising-type. Under external magnetic field perpendicular to

  43. Andrew Berget, Sen-Peng Eu, Victor Reiner

    We show how to derive new instances of the cyclic sieving phenomenon from old ones via elementary representation theory. Examples are given involving objects such as words, parking functions, finite fields, and graphs.

  44. Jesus Gonzalez, Peter Landweber

    We compute the integral homology and cohomology groups of configuration spaces of two distinct points on a given real projective space. The explicit answer is related to the (known multiplicative structure in the) integral cohomology---with simple and twisted coefficients---of the dihedral group of order 8 (in the case of unordered configurations) and the el

  45. Jungjai Lee, Hyun Seok Yang

    We review a novel and authentic way to quantize gravity. This novel approach is based on the fact that Einstein gravity can be formulated in terms of a symplectic geometry rather than a Riemannian geometry in the context of emergent gravity. An essential step for emergent gravity is to realize the equivalence principle, the most important property in the the

  46. Ilijas Farah, Bradd Hart, David Sherman

    We introduce a version of logic for metric structures suitable for applications to C*-algebras and tracial von Neumann algebras. We also prove a purely model-theoretic result to the effect that the theory of a separable metric structure is stable if and only if all of its ultrapowers associated with nonprincipal ultrafilters on N are isomorphic even when the

  47. Yurii Lyubarskii, Roman Vershynin

    Given a frame in C^n which satisfies a form of the uncertainty principle (as introduced by Candes and Tao), it is shown how to quickly convert the frame representation of every vector into a more robust Kashin's representation whose coefficients all have the smallest possible dynamic range O(1/\sqrt{n}). The information tends to spread evenly among these

  48. Catalin Barbu

    In this note, we present a proof of Smarandache's cevian triangle hyperbolic theorem in the Einstein relativistic velocity model of hyperbolic geometry.

  49. Kathleen L. Petersen, Christopher D. Sinclair

    Given a fixed quadratic extension K of Q, we consider the distribution of elements in K of norm 1 (denoted N). When K is an imaginary quadratic extension, N is naturally embedded in the unit circle in C and we show that it is equidistributed with respect to inclusion as ordered by the absolute Weil height. By Hilbert's Theorem 90, an element in N can be

  50. Justin H. Howell, Lee Armus, Joseph M. Mazzarella, Aaron S. Evans

    The Great Observatories All-sky LIRG Survey (GOALS) consists of a complete sample of 202 Luminous Infrared Galaxies (LIRGs) selected from the IRAS Revised Bright Galaxy Sample (RBGS). The galaxies span the full range of interaction stages, from isolated galaxies to interacting pairs to late stage mergers. We present a comparison of the UV and infrared proper

  51. Motoaki Saruwatari, Masa-aki Hashimoto

    Effects of a new triple-alpha reaction rate on the ignition of carbon-oxygen white dwarfs accreting helium in a binary systems have been investigated. The ignition points determine the properties of a thermonuclear explosion of a Type Ia supernova. We examine the cases of different accretion rates of helium and different initial masses of the white dwarf, wh

  52. Byoung S. Ham

    Atomic population transfer in an inhomogeneously broadened optical medium is analyzed for on-demand photon storage-time control in both atomic frequency comb (AFC) and phase locked echoes. In AFC the photon storage mechanism belongs to the conventional three-pulse photon echoes, while the storage time control is limited by conventional two-pulse photon echoe

  53. Germán J. de Valcárcel, Eugenio Roldán, Alejandro Romanelli

    We study the evolution of initially extended distributions in the coined quantum walk on the line by analyzing the dispersion relation of the process and its associated wave equations. This allows us, in particular, to devise an initially extended condition leading to a uniform probability distribution whose width increases linearly with time, with increasin

  54. L. S. Borkowski

    We study the response of a Hodgkin-Huxley neuron stimulated by a periodic sequence of conductance pulses arriving through the synapse in the high frequency regime. In addition to the usual excitation threshold there is a smooth crossover from the firing to the silent regime for increasing pulse amplitude $g_{syn}$. The amplitude of the voltage spikes decreas

  55. Marcelo Jaime

    Production of very high magnetic fields in the laboratory has relentlessly increased in quantity and quality over the last five decades, and a shift occurred from research focused in magnet technology to studies of the fundamental physics of novel materials in high fields. New strategies designed to understand microscopic mechanisms at play in materials surf

  56. Jade C. Bond, David P. O'Brien, Dante S. Lauretta

    Extrasolar planet host stars have been found to be enriched in key planet-building elements. These enrichments have the potential to drastically alter the composition of material available for terrestrial planet formation. Here we report on the combination of dynamical models of late-stage terrestrial planet formation within known extrasolar planetary system

  57. Ilan Lobel, Asuman Ozdaglar, Diego Feijer

    We study distributed algorithms for solving global optimization problems in which the objective function is the sum of local objective functions of agents and the constraint set is given by the intersection of local constraint sets of agents. We assume that each agent knows only his own local objective function and constraint set, and exchanges information w

  58. Yoseph Imry, Ariel Amir

    The Anderson localization transition is considered at finite temperatures. This includes the electrical conductivity as well as the electronic thermal conductivity and the thermoelectric coefficients. An interesting critical behavior of the latter is found. A method for characterizing the conductivity critical exponent, an important signature of the transiti

  59. Alain Jeanneret, Samuel Wuethrich

    We construct a free and transitive action of the group of bilinear forms Bil(I/I^2[1]) on the set of R-products on F, a regular quotient of an E-infinity ring spectrum R with F_* \cong R_*/I. We show that this action induces a free and transitive action of the group of quadratic forms QF(I/I^2[1]) on the set of equivalence classes of R-products on F. The cha

  60. Federico Demartin, Stefano Forte, Elisa Mariani, Juan Rojo

    We present a systematic study of uncertainties due to parton distributions and the strong coupling on the gluon-fusion production cross section of the Standard Model Higgs at the Tevatron and LHC colliders. We compare procedures and results when three recent sets of PDFs are used, CTEQ6.6, MSTW08 and NNPDF1.2, and we discuss specifically the way PDF and stro

  61. Sean T. McWilliams, Bernard J. Kelly, John G. Baker

    Advances in the field of numerical relativity now make it possible to calculate the final, most powerful merger phase of binary black-hole coalescence for generic binaries. The state of the art has advanced well beyond the equal-mass case into the unequal-mass and spinning regions of parameter space. We present a study of the nonspinning portion of parameter

  62. Mukremin Kilic, Jeffrey A. Munn, Kurtis A. Williams, P. M. Kowalski

    We report the discovery of three nearby old halo white dwarf candidates in the Sloan Digital Sky Survey (SDSS), including two stars in a common proper motion binary system. These candidates are selected from our 2800 square degree proper motion survey on the Bok and U.S. Naval Observatory Flagstaff Station 1.3m telescopes, and they display proper motions of

  63. A. Garg, K. H. Cook, S. Nikolaev, M. E. Huber

    We present 2323 High-Amplitude δ-Scuti (HADS) candidates discovered in the Large Magellanic Cloud (LMC) by the SuperMACHO survey (Rest et al. 2005). Frequency analyses of these candidates reveal that several are multimode pulsators, including 119 whose largest amplitude of pulsation is in the fundamental (F) mode and 19 whose largest amplitude of pulsation i

  64. Kyle W. Willett, John T. Stocke, Jeremy Darling, Eric S. Perlman

    We present low- and high-resolution mid-infrared (mid-IR) spectra and photometry for eight compact symmetric objects (CSOs) taken with the Infrared Spectrograph on the Spitzer Space Telescope. The hosts of these young, powerful radio galaxies show significant diversity in their mid-IR spectra. This includes multiple atomic fine-structure lines, H2 gas, polyc

  65. R. Poleski, I. Soszyński, A. Udalski, M. K. Szymański

    The sixth part of the OGLE-III catalog of Variable Stars presents δSct pulsators in the Large Magellanic Cloud. Altogether 2786 variable stars were found and amongst them 92 are multi-mode objects, including 67 stars pulsating in the fundamental mode and the first overtone (F/1O), nine double-mode pulsators with various combinations of the first three overto

  66. Andreas Koch, R. Michael Rich

    We present a statistical characterization of the carbon-star to M-giant (C/M) ratio in the halo of M31. Based on application of pseudo-filter band passes to our Keck/DEIMOS spectra we measure the 81-77-color index of 1288 stars in the giant stellar stream and in halo fields out to large distances. From this well-established narrow-band system, supplemented b

  67. I. Martin, Gábor B. Halász, L. N. Bulaevskii, A. E. Koshelev

    We show that shunt capacitor stabilizes synchronized oscillations in intrinsic Josephson junction stacks biased by DC current. This synchronization mechanism has an effect similar to the previously discussed radiative coupling between junctions, however, it is not defined by the geometry of the stack. It is particularly important in crystals with smaller num

  68. N. Lugaz, J. N. Hernandez-Charpak, I. I. Roussev, C. J. Davis

    We discuss how simultaneous observations by multiple heliospheric imagers can provide some important information about the azimuthal properties of Coronal Mass Ejections (CMEs) in the heliosphere. We propose two simple models of CME geometry that can be used to derive information about the azimuthal deflection and the azimuthal expansion of CMEs from SECCHI/

  69. S. Chu, T. M. McQueen, R. Chisnell, D. E. Freedman

    Spin-frustrated systems are one avenue for inducing macroscopic quantum states in materials. However, experimental realization of this goal has been difficult because of the lack of simple materials and, if available, the separation of the unusual magnetic properties arising from exotic magnetic states from behavior associated with chemical disorder, such as

  70. E. H. El Abdalaoui, M. Lemanczyk

    For some countable discrete torsion Abelian groups we give examples of their finite measure-preserving actions which have simple spectrum and no approximate transitivity property.

  71. Christopher Orme

    Within the LAGUNA design study, seven candidate sites are being assessed for their feasibility to host a next-generation, very large neutrino observatory. Such a detector will be expected to feature within a future European accelerator neutrino programme (Superbeam or Beta Beam), and hence the distance from CERN is of critical importance. In this article, th

  72. D. A. Mitchell, J. G. Robertson, R. J. Sault

    In radio astronomy, reference signals from auxiliary antennas that receive only the radio frequency interference (RFI) can be modified to model the RFI environment at the astronomy receivers. The RFI can then be canceled from the astronomy signal paths. However, astronomers typically only require signal statistics. If the RFI statistics are changing slowly,

  73. P. E. Williams, W. D. Pesnell

    Solar supergranulation plays an important role in generating and structuring the solar magnetic field and as a mechanism responsible for the 11-year solar cycle. It is clearly detected within SOHO/MDI Dopplergrams, from which a variety of properties may be derived. Techniques that extract spatial, temporal and kinematic characteristics and provide comparison

  74. B. M. Rubenstein, J. E. Gubernatis, J. D. Doll

    We propose a modified power method for computing the subdominant eigenvalue $λ_2$ of a matrix or continuous operator. Here we focus on defining simple Monte Carlo methods for its application. The methods presented use random walkers of mixed signs to represent the subdominant eigenfuction. Accordingly, the methods must cancel these signs properly in order to

  75. Stevens Le Blond, Arnaud Legout, Fabrice Le Fessant, Walid Dabbous

    This paper presents a set of exploits an adversary can use to continuously spy on most BitTorrent users of the Internet from a single machine and for a long period of time. Using these exploits for a period of 103 days, we collected 148 million IPs downloading 2 billion copies of contents. We identify the IP address of the content providers for 70% of the Bi

  76. Maurice Robert Kibler

    Bases of finite-dimensional Hilbert spaces (in dimension d) of relevance for quantum information and quantum computation are constructed from angular momentum theory and su(2) Lie algebraic methods. We report on a formula for deriving in one step the (1+p)p qupits (i.e., qudits with d = p a prime integer) of a complete set of 1+p mutually unbiased bases in C

  77. Sara Maad Sasane, Amol Sasane

    Let $C$ denote a closed convex cone $C$ in $\mathbb{R}^d$ with apex at 0. We denote by $\mathcal{E}'(C)$ the set of distributions having compact support which is contained in $C$. Then $\mathcal{E}'(C)$ is a ring with the usual addition and with convolution. We give a necessary and sufficient analytic condition on $\hat{f}_1,..., \hat{f}_n$ for $f_1,

  78. Rishi Sharma, Sanjay Reddy

    We calculate the screening of the ion-ion potential due to electrons in the presence of a large background magnetic field, at densities of relevance to neutron star crusts. Using the standard approach to incorporate electron screening through the one-loop polarization function, we show that the magnetic field produces important corrections both at short and

  79. Mariafelicia De Laurentis

    This review paper is devoted to the theory of orbits. We start with the discussion of the Newtonian problem of motion then we consider the relativistic problem of motion, in particular the PN approximation and the further gravitomagnetic corrections. Finally by a classification of orbits in accordance with the conditions of motion, we calculate the gravitati

  80. Andreas Fring, Monique Smith

    We construct complex root spaces remaining invariant under antilinear involutions related to all Coxeter groups. We provide two alternative constructions: One is based on deformations of factors of the Coxeter element and the other based on the deformation of the longest element of the Coxeter group. Motivated by the fact that non-Hermitian Hamiltonians admi

  81. Junwei Zhang, Mustafa Cenk Gursoy

    In this paper, collaborative use of relays to form a beamforming system with the aid of perfect channel state information (CSI) and to provide communication in physicallayer security between a transmitter and two receivers is investigated. In particular, we describe decode-and-forward based null space beamforming schemes and optimize the relay weights jointl

  82. C. Henkel, K. M. Menten, M. T. Murphy, V. V. Flambaum

    Observing inversion lines of ammonia (NH3), complemented by rotational lines of NH3 and other molecular species, provides stringent constraints on potential variations of the proton-to-electron mass ratio. While a limit of one part per million is derived for a lookback time of 7 billion years, nearby dark clouds might show a statistically significant variati

  83. Jalmar M. F. Carrasco, Silvia L. P. Ferrari, Gauss M. Cordeiro

    A new five-parameter continuous distribution which generalizes the Kumaraswamy and the beta distributions as well as some other well-known distributions is proposed and studied. The model has as special cases new four- and three-parameter distributions on the standard unit interval. Moments, mean deviations, Rényi's entropy and the moments of order stati

  84. Taiga Yasuda, Masahito Tada-Umezaki, Mikio Nakahara, Tomonari Wakabayashi

    Entanglement control of qubits in a photoisomerizing molecule is studied in the context of an NMR quantum computer by taking azobenzene as an example. Azobenzene has two different isomers, {\it{}trans}-azobenzene (TAB) and {\it{}cis}-azobenzene (CAB), which can be interconverted by photoisomerization. Changing molecular structure leads to change in the spin-

  85. Rouchdi Bahloul

    We propose a general study of standard bases of polynomial ideals with parameters in the case where the monomial order is arbitrary. We give an application to the computation of the stratification by the local Hilbert-Samuel function. Moreover, we give an explicit upper bound for the degree of a standard basis for an arbitrary order and also for the number o

  86. Sami Akin, Mustafa Cenk Gursoy

    In this paper, cognitive transmission under quality of service (QoS) constraints is studied. In the cognitive radio channel model, it is assumed that both the secondary receiver and the secondary transmitter know the channel fading coefficients perfectly and optimize the power adaptation policy under given constraints, depending on the channel activity of th

  87. F. Castro, J. Gago, I. Hartillo, J. Puerto

    Integer variables allow the treatment of some portfolio optimization problems in a more realistic way and introduce the possibility of adding some natural features to the model. We propose an algebraic approach to maximize the expected return under a given admissible level of risk measured by the covariance matrix. To reach an optimal portfolio it is an esse

  88. G. Chincarini, J. Mao, R. Margutti, M. G. Bernardini

    We present an updated catalog of 113 X-ray flares detected by Swift in the ~33% of the X-ray afterglows of Gamma-Ray Bursts (GRB). 43 flares have a measured redshift. For the first time the analysis is performed in 4 different X-ray energy bands, allowing us to constrain the evolution of the flare temporal properties with energy. We find that flares are narr

  89. Sanjeev Kumar, Suneel Kumar, Rajeev K. Puri

    We present a complete systematics (excitation function, impact parameter, system size, isospin asymmetry, and equations of state dependences) of global stopping and fragment production for heavy-ion reactions in the energy range between 50 and 1000 MeV/nucleon in the presence of symmetry energy and an isospin-dependent cross section. It is observed that the

  90. Junwei Zhang, Mustafa Cenk Gursoy

    In this paper, collaborative use of relays to form a beamforming system and provide physical-layer security is investigated. In particular, amplify-and-forward (AF) relay beamforming designs under total and individual relay power constraints are studied with the goal of maximizing the secrecy rates when perfect channel state information (CSI) is available. I

  91. Qing Chen, Mustafa Cenk Gursoy

    In this paper, we have studied the energy efficiency of cooperative networks operating in either the fixed Amplifyand- Forward (AF) or the selective Decode-and-Forward (DF) mode. We consider the optimization of the M-ary quadrature amplitude modulation (MQAM) constellation size to minimize the bit energy consumption under given bit error rate (BER) constrain

  92. Sanjeev Kumar, Suneel Kumar, Rajeev K. Puri

    The elliptical flow of fragments is studied for different systems at incident energies between 50 and 1000 MeV/nucleon using the isospin-dependent quantum molecular dynamics (IQMD) model. Our findings reveal that elliptical flow shows a transition from positive (in-plane) to negative (out-of-plane) values in the midrapidity region at a certain incident energ

  93. D. Perez Daroca, G. S. Lozano, G. Pasquini, V. Bekeris

    We study the different dynamical regimes of a vortex lattice driven by AC forces in the presence of random pinning via numerical simulations. The behaviour of the different observables is charaterized as a function of the applied force amplitude for different frequencies. We discuss the inconveniences of using the mean velocity to identify the depinnig trans

  94. Deli Qiao, Mustafa Cenk Gursoy, Senem Velipasalar

    In this paper, the fading broadcast channel with confidential messages is studied in the presence of statistical quality of service (QoS) constraints in the form of limitations on the buffer length. We employ the effective capacity formulation to measure the throughput of the confidential and common messages. We assume that the channel side information (CSI)

  95. Deli Qiao, Mustafa Cenk Gursoy, Senem Velipasalar

    In this paper, the secure transmission of information over an ergodic fading channel is investigated in the presence of statistical quality of service (QoS) constraints. We employ effective capacity, which provides the maximum constant arrival rate that a given process can support while satisfying statistical delay constraints, to measure the secure throughp

  96. Krzysztof Putyra

    There are two categorifications of the Jones polynomial: "even" discovered by M.Khovanov in 1999 and "odd" dicovered by P.Ozsvath, J.Rasmussen and Z.Szabo in 2007. The first one can be fully constructed in the category of cobordisms (strictly: in the additive closure of that category), where we can build a complex for a given tangle and show

  97. William Matthews, Marco Piani, John Watrous

    We study the power of measurements implementable with local quantum operations and classical communication (or LOCC measurements for short) in the setting of quantum channel discrimination. More precisely, we consider discrimination procedures that attempt to identify an unknown channel, chosen uniformly from two known alternatives, that take the following f

  98. P. A. Boyle, J. M. Flynn, A. Juttner, C. Kelly

    Using partially twisted boundary conditions we compute the K->pi semi-leptonic form factors in the range of momentum transfers 0 <~ q^2 <= q^2_{max}=(mK-mpi)^2 in lattice QCD with N_f=2+1 dynamical flavours. In this way we are able to determine f+(0) without any interpolation in the momentum transfer, thus eliminating one source of systematic error. This stu

  99. V. B. Bobrov, S. A. Trigger

    It is shown that in adiabatic approximation for nuclei the many-component Coulomb system cannot be described on the basis of the grand canonical ensemble. Using the variational Bogolyubov&#39;s procedure for the free energy, the Hohenberg-Kohn theorem is proved in the canonical ensemble for inhomogeneous electron gas at finite temperature. The principal diff

  100. Daniel E. Lopez-Fogliani

    The $μν$SSM proposes to use right-handed neutrino supermultiplets in order to generate the $μ$ term and neutrino masses simultaneously. We discuss neutrino physics and the associated electroweak seesaw mechanism in this model. We show how to obtain, from the neutralino-neutrino mass matrix of the $μν$SSM, the effective neutrino mass matrix. In particular we