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October 2010 arXiv papers — page 21

Showing 2,0012,100 of 6,460 papers

  1. Orsola De Marco, Jean-Claude Passy, Maxwell Moe, Falk Herwig

    The α-formalism is a common way to parametrize the common envelope interaction between a giant star and a more compact companion. The α parameter describes the fraction of orbital energy released by the companion that is available to eject the giant star's envelope. By using new, detailed stellar evolutionary calculations we derive a user-friendly prescr

  2. Nopmanee Supanam, Harold W. Fearing, Yupeng Yan

    We construct the general pion-nucleon SU(2) Lagrangian including both virtual photons and leptons for relativistic baryon chiral perturbation theory up to fourth order. We include the light leptons as explicit dynamical degrees of freedom by introducing new building blocks which represent these leptons.

  3. Hideyuki Ishi, Satoshi Yamaji

    We describe the Bergman kernel of any bounded homogeneous domain in a minimal realization relating to the Bergman kernels of the Siegel disks. Taking advantage of this expression, we obtain substantial estimates of the Bergman kernel of the homogeneous domain.

  4. Muktish Acharyya

    The two dimensional ferromagnetic Ising model in the presence of a propagating magnetic field wave (with well defined frequency and wavelength) is studied by Mone Carlo simulation. This study differs from all of the earlier studies done so far, where the oscillating magnetic field was considered to be uniform in space. The time average magnetisation over a f

  5. Atsushi Shiho

    In this paper, we introduce the notion of parabolic log convergent isocrystals on smooth varieties endowed with a simple normal crossing divisor, which is a kind of $p$-adic analogue of the notion of parabolic bundles on smooth varieties defined by Seshadri, Maruyama-Yokogawa, Iyer-Simpson, Borne. We prove that the equivalence between the category of $p$-adi

  6. Xin-Zhong Yan, C. S. Ting

    Using the self-consistent Hartree-Fock approximation, we study the compressibility instability of the interacting electrons in bilayer graphene. The chemical potential and the compressibility of the electrons can be significantly altered by an energy gap (tunable by external gate voltages) between the valence and conduction bands. For zero gap case, we show

  7. Howard Baer, Senarath de Alwis, Kevin Givens, Shibi Rajagopalan

    Gaugino AMSB models-- wherein scalar and trilinear soft SUSY breaking terms are suppressed at the GUT scale while gaugino masses adopt the AMSB form-- yield a characteristic SUSY particle mass spectrum with light sleptons along with a nearly degenerate wino-like lightest neutralino and quasi-stable chargino. The left- sleptons and sneutrinos can be pair prod

  8. Mordecai Waegell, P. K. Aravind, Norman D. Megill, Mladen Pavicic

    The set of 60 real rays in four dimensions derived from the vertices of a 600-cell is shown to possess numerous subsets of rays and bases that provide basis-critical parity proofs of the Bell-Kochen-Specker (BKS) theorem (a basis-critical proof is one that fails if even a single basis is deleted from it). The proofs vary considerably in size, with the smalle

  9. Jun-Li Xin, J. -Q. Liang

    We study the quantum-classical correspondence in terms of coherent wave functions of a charged particle in two-dimensional central-scalar-potentials as well as the gauge field of a magnetic flux in the sense that the probability clouds of wave functions are well localized on classical orbits. For both closed and open classical orbits, the non-integer angular

  10. Akihito Soeda, Yoshiyuki Kinjo, Peter S. Turner, Mio Murao

    In order to investigate distributed quantum computation under restricted network resources, we introduce a quantum computation task over the butterfly network where both quantum and classical communications are limited. We consider deterministically performing a two-qubit global unitary operation on two unknown inputs given at different nodes, with outputs a

  11. Yin-Yang Shen, Xiao-Juan Yuan, Xiang-Mu Kong

    The dynamics of the one-dimensional spin-1/2 quantum XXZ model with random fields is investigated by the recurrence relations method. When the fields satisfy the bimodal distribution, the system shows a crossover between a collective-mode behavior and a central-peak one with increasing field while the anisotropy parameter Δ is small; a disordered behavior re

  12. A. Connolly

    We report on the status of the Salt Sensor Array (SalSA), a proposed experiment for detecting ultra-high energy neutrinos through the radio \v{C}erenkov technique with an array of radio-microwave antennas embedded in a large, naturally occurring salt formation. We review the measurements to date aimed at assessing SalSA's feasibility, including a return visi

  13. Alexandre Belloni, Daniel Chen, Victor Chernozhukov, Christian Hansen

    We develop results for the use of Lasso and Post-Lasso methods to form first-stage predictions and estimate optimal instruments in linear instrumental variables (IV) models with many instruments, $p$. Our results apply even when $p$ is much larger than the sample size, $n$. We show that the IV estimator based on using Lasso or Post-Lasso in the first stage i

  14. Shiwu Yang

    We consider the problem of small data global existence for a class of semilinear wave equations with null condition on a Lorentzian background $(\mathbb{R}^{3+1}, g)$ with a \textbf{time dependent metric $g$} coinciding with Minkowski metric outside the cylinder $\{(t, x)| |x|\leq R\}$. We show that the small data global existence result can be reduced to tw

  15. Eduardo V. Flores

    We assume that particles are point-like objects even when not observed. We report on the consequences of our assumption within the realm of quantum theory. An important consequence is the necessity of vacuum fields to account for particle dynamics. The zero-point energy is evidence of the reality of vacuum fields. The dynamics of vacuum fields depends on wav

  16. Jean Jacod, Viktor Todorov

    We consider a process $X_t$, which is observed on a finite time interval $[0,T]$, at discrete times $0,Δ_n,2Δ_n,\ldots.$ This process is an Itô semimartingale with stochastic volatility $σ_t^2$. Assuming that $X$ has jumps on $[0,T]$, we derive tests to decide whether the volatility process has jumps occurring simultaneously with the jumps of $X_t$. There ar

  17. J. Kallsen, J. Muhle-Karbe

    In frictionless markets, utility maximization problems are typically solved either by stochastic control or by martingale methods. Beginning with the seminal paper of Davis and Norman [Math. Oper. Res. 15 (1990) 676--713], stochastic control theory has also been used to solve various problems of this type in the presence of proportional transaction costs. Ma

  18. Pablo Azcue, Nora Muler

    We consider in this paper the optimal dividend problem for an insurance company whose uncontrolled reserve process evolves as a classical Cramér--Lundberg process. The firm has the option of investing part of the surplus in a Black--Scholes financial market. The objective is to find a strategy consisting of both investment and dividend payment policies which

  19. Daniel Fernholz, Ioannis Karatzas

    In a Markovian model for a financial market, we characterize the best arbitrage with respect to the market portfolio that can be achieved using nonanticipative investment strategies, in terms of the smallest positive solution to a parabolic partial differential inequality; this is determined entirely on the basis of the covariance structure of the model. The

  20. Bertrand I. Halperin, Ady Stern, Izhar Neder, Bernd Rosenow

    We analyze interference phenomena in the quantum-Hall analog of the Fabry-Perot interferometer, exploring the roles of the Aharonov-Bohm effect, Coulomb interactions, and fractional statistics on the oscillations of the resistance as one varies the magnetic field B and/or the voltage V_G applied to a side gate. Coulomb interactions couple the interfering edg

  21. A. M. Mathai, H. J. Haubold, C. Tsallis

    The established technique of eliminating upper or lower parameters in a general hypergeometric series is profitably exploited to create pathways among confluent hypergeometric functions, binomial functions, Bessel functions, and exponential series. One such pathway, from the mathematical statistics point of view, results in distributions which naturally emer

  22. Timothy Trudgian

    This paper contains a small improvement to the explicit bounds on the growth of the function $S(T)$. It is shown how more substantial improvements are possible if one has better explicit bounds on the growth of $|ζ(\frac{1}{2}+it)|$.

  23. Jianda Wu, Lijun Zhu, Qimiao Si

    Entropy accumulation near a quantum critical point was expected based on general scaling arguments, and has recently been explicitly observed. We explore this issue further in two canonical models for quantum criticality, with particular attention paid to the potential effects beyond hyperscaling. In the case of a one-dimensional transverse field Ising model

  24. C. -Y. Ng, V. M. Kaspi

    Anomalous X-ray pulsars and soft gamma repeaters have recently emerged as a unified class of neutron stars, identified by dramatic X-ray and gamma-ray outbursts and via luminous X-ray pulsations, both thought to be powered by the decay of an enormous internal magnetic field. This "magnetar" hypothesis has raised the question of these objects' phy

  25. Ran Cheng, Qian Niu

    A rigorous proof is given on the equivalence of the O(3) nonlinear sigma model and the CP1 model via path integral approach.

  26. T. Kallinger, B. Mosser, S. Hekker, D. Huber

    Clear power excess in a frequency range typical for solar-type oscillations in red giants has been detected in more than 1000 stars, which have been observed during the first 138 days of the science operation of the NASA Kepler satellite. This sample includes stars in a wide mass and radius range with spectral types G and K, extending in luminosity from the

  27. Natalya Kovaleva, Leonid Manevitch

    Physico-mechanical properties of polymers in solid state, in particular conditions of their structural transformations, are substantially defined by existence and mobility of elementary nonlinear excitations. The localized oscillatory excitations (breathers) which have been revealed in crystalline PE are important for thermodynamic studies. In the given work

  28. Se-Wan Ji, Jaewan Kim, Hai-Woong Lee, M. S. Zubairy

    We derive two classes of multi-mode Bell inequalities under local realistic assumptions, which are violated only by the entangled states negative under partial transposition in accordance with the Peres conjecture. Remarkably, the failure of local realism can be manifested by exploiting wave and particle correlations of readily accessible continuous-variable

  29. Roland Kothes

    There is a growing community of astronomers presenting evidence that the pulsar wind nebula 3C58 is much older than the connection with the historical supernova of A.D 1181 would indicate. Most of the strong evidence against a young age for 3C58 relies heavily on the assumed distance of 3.2 kpc determined with HI absorption measurements. I have revisited thi

  30. N. Madhusudhan, S. Seager

    Several studies in the recent past have inferred the existence of thermal inversions in some transiting hot Jupiter atmospheres. Given the limited data available, the inference of a thermal inversion depends critically on the chemical composition assumed for the atmosphere. In this study, we explore the degeneracies between thermal inversions and molecular a

  31. Roland Duclous, John Kirk, Anthony Bell

    Gamma-ray and electron-positron pair production will figure prominently in laser-plasma experiments with next generation lasers. Using a Monte Carlo approach we show that straggling effects arising from the finite recoil an electron experiences when it emits a high energy photon, increase the number of pairs produced on further interaction with the laser fie

  32. P. G. Bizzeti, A. M. Bizzeti-Sona, D. Tonev, A. Giannatiempo

    To investigate the possible X(5) character of 122Ba, suggested by the ground state band energy pattern, the lifetimes of the lowest yrast states of 122Ba have been measured, via the Recoil Distance Doppler-Shift method. The relevant levels have been populated by using the 108Cd(16O,2n)122Ba and the 112Sn(13C,3n)122Ba reactions. The B(E2) values deduced in th

  33. Tom Eccles

    For integers $m_1,...,m_d>0$ and a cuboid $M=[0,m_1]\times ... \times [0,m_d]\subset \mathbb{R}^d$, a brick of $M$ is a closed cuboid whose vertices have integer coordinates. A set $H$ of bricks in $M$ is a system of brick islands if for each pair of bricks in $H$ one contains the other or they are disjoint. Such a system is maximal if it cannot be extended

  34. Miranda C. N. Cheng, Robbert Dijkgraaf, Cumrun Vafa

    We give a non-perturbative completion of a class of closed topological string theories in terms of building blocks of dual open strings. In the specific case where the open string is given by a matrix model these blocks correspond to a choice of integration contour. We then apply this definition to the AGT setup where the dual matrix model has logarithmic po

  35. Daniel Thomas, Claudia Maraston, Jonas Johansson

    We present new stellar population models of Lick absorption-line indices with variable element abundance ratios. The models are based on our new calibrations of absorption-line indices with stellar parameters derived from the MILES stellar library. The key novelty compared to our previous models is that they are now available at the higher spectral resolutio

  36. D. Huber, T. R. Bedding, D. Stello, B. Mosser

    We have studied solar-like oscillations in ~800 red-giant stars using Kepler long-cadence photometry. The sample includes stars ranging in evolution from the lower part of the red-giant branch to the Helium main sequence. We investigate the relation between the large frequency separation (Delta nu) and the frequency of maximum power (nu_max) and show that it

  37. Joseph H. Silverman

    In the moduli space of polynomials of degree 3 with marked critical points c_1 and c_2, let C_{1,n} be the locus of maps for which c_1 has period n and let C_{2,m} be the locus of maps for which c_2 has period m. A consequence of Thurston's rigidity theorem is that the curves C_{1,n} and C_{2,m} intersect transversally. We give a purely algebraic proof t

  38. A. K. Zvezdin, D. I. Plokhov

    Full magnetization process of magnetic nanocluster Mn4, including all its actual multiplets, is theoretically investigated. The formulas needed to determine the exchange constants of cluster Mn4 from experimental data are obtained. It is shown that quantum jumps of magnetization of this nanocluster are in area of megagauss magnetic fields. Remarkable feature

  39. Alan Kostelecky

    This talk given at the CPT'10 meeting provides a brief introduction to Lorentz and CPT violation and outlines a few recent developments in the subject.

  40. R. Esquivel-Sirvent, G. H. Cocoletzi, M. Palomono-Ovando

    We present a method for inducing and controlling van der Waals torques between two parallel slabs using a constant magnetic field. The torque is calculated using the Barash theory of dispersive torques. In III-IV semiconductors such as $InSb$, the effect of an external magnetic field is to induce an optical anisotropy, in an otherwise isotropic material, tha

  41. V. A. Khodel, J. W. Clark, M. V. Zverev

    The low-temperature kinetics of the strongly correlated electron liquid inhabiting a solid is analyzed. It is demonstrated that a softly damped branch of transverse zero sound emerges when several bands cross the Fermi surface simultaneously near a quantum critical point at which the density of states diverges. Suppression of the damping of this branch occur

  42. George Wilson

    Let X be a complex affine curve (not isomorphic to the affine line), and let Pic(D) be the group of autoequivalences of the category of D(X)-modules. Cannings and Holland have shown that Pic(D) fits into an exact sequence in which the other groups can be considered known: we show that this sequence is split.

  43. P. Wicke, S. Whitlock, N. J. van Druten

    Experiments on ultracold gases offer unparalleled opportunities to explore quantum many-body physics, with excellent control over key parameters including temperature, density, interactions and even dimensionality. In some systems, atomic interactions can be adjusted by means of magnetic Feshbach resonances, which have played a crucial role in realizing new

  44. Robbert Dijkgraaf, Hiroyuki Fuji, Masahide Manabe

    We study the relation between perturbative knot invariants and the free energies defined by topological string theory on the character variety of the knot. Such a correspondence between SL(2;C) Chern-Simons gauge theory and the topological open string theory was proposed earlier on the basis of the volume conjecture and AJ conjecture. In this paper we discus

  45. S. A. Leonel, I. A. Marques, P. Z. Coura, B. V. Costa

    We use Monte Carlo simulation to study the vortex nucleation on magnetic nanodots at low temperature. In our simulations, we have considered a simple microscopic two-dimensional anisotropic Heisenberg model with term to describe the anisotropy due to the presence of the nanodot edge. We have considered the thickness of the edge, which was not considered in p

  46. A. S. T. Pires, B. V. Costa, R. A. Dias

    The phase diagram of the quasi-two-dimensional easy-plane antiferromagnetic model, with a magnetic field applied in the easy plane, is studied using the self-consistent harmonic approximation. We found a linear dependence of the transition temperature as a function of the field for large values of the field. Our results are in agreement with experimental dat

  47. Luigi Brugnano, Felice Iavernaro, Donato Trigiante

    When numerically integrating canonical Hamiltonian systems, the long-term conservation of some of its invariants, among which the Hamiltonian function itself, assumes a central role. The classical approach to this problem has led to the definition of symplectic methods, among which we mention Gauss-Legendre collocation formulae. Indeed, in the continuous set

  48. M. Rapini, R. A. Dias, B. V. Costa

    Ultrathin magnetic films can be modeled as an anisotropic Heisenberg model with long-range dipolar interactions. It is believed that the phase diagram presents three phases: An ordered ferromagnetic phase I, a phase characterized by a change from out-of-plane to in-plane in the magnetization II, and a high-temperature paramagnetic phase III. It is claimed th

  49. J. C. S. Rocha, P. Z. Coura, S. A. Leonel, R. A. Dias

    The existence of nonlinear objects of the vortex type in two-dimensional magnetic systems presents itself as one of the most promising candidates for the construction of nanodevices, useful for storing data, and for the construction of reading and writing magnetic heads. The vortex appears as the ground state of a magnetic nanodisk whose magnetic moments int

  50. J. E. R. Costa, B. V. Costa

    By using a simulated annealing approach, Monte Carlo and molecular-dynamics techniques we have studied static and dynamic behavior of the classical two-dimensional anisotropic Heisenberg model. We have obtained numerically that the vortex developed in such a model exhibit two different behaviors depending if the value of the anisotropy $λ$ lies below or abov

  51. Enrico Priola, Jerzy Zabczyk, Lihu Xu

    We show how gradient estimates for transition semigroups can be used to establish exponential mixing for a class of Markov processes in infinite dimensions. We concentrate on semilinear systems driven by cylindrical $α$-stable noises, $α\in (0,2)$, introduced in Priola-Zabczyk "Structural properties of semilinear SPDEs driven by cylindrical stable proces

  52. Jerzy Marcinkowski, Jakub Michaliszyn

    The Halpern-Shoham logic is a modal logic of time intervals. Some effort has been put in last ten years to classify fragments of this beautiful logic with respect to decidability of its satisfiability problem. We contribute to this effort by showing - what we believe is quite an unexpected result - that the logic of subintervals, the fragment of the Halpern-

  53. N. V. Elkina, A. M. Fedotov, I. Yu. Kostyukov, M. V. Legkov

    The results of Monte-Carlo simulations of electron-positron-photon cascades initiated by slow electrons in circularly polarized fields of ultra-high strength are presented and discussed. Our results confirm previous qualitative estimations [A.M. Fedotov, et al., PRL 105, 080402 (2010)] of the formation of cascades. This sort of cascades has revealed the new

  54. Mauro Cambiaso, Luis F. Urrutia

    In the Einstein-Cartan formulation, an iterative procedure to find solutions in non-dynamical Chern-Simons (CS) gravity in vacuum is proposed. The iterations, in powers of a small parameter $β$ which codifies the CS coupling, start from an arbitrary torsionless solution of Einstein equations. With Schwarzschild as the zeroth-order choice, we derive a second-

  55. Marco Zamparo

    I investigate a disordered version of a simplified model of protein folding, with binary degrees of freedom, applied to an ideal beta-hairpin structure. Disorder is introduced by assuming that the contact energies are independent and identically distributed random variables. The equilibrium free-energy of the model is studied, performing the exact calculatio

  56. Guang Shi

    This article generalize the classical Goldstine-Weston theorem on normed spaces to one on random normed modules: the image of a random normed module $(E,\|\cdot\|)$ under the random natural embedding $J$ is dense in its double random conjugate space $E^{**}$ with respect to the $(ε,λ)$ weak star topology; and $J(E)$ is also dense in $E^{**}$ with respect to

  57. H. Moutarde

    Working at twist 2 accuracy and assuming the dominance of the Generalized Parton Distribution H we study the helicity-dependent and independent cross sections measured in Hall A, the beam spin asymmetries measured in Hall B at Jefferson Laboratory and beam charge, beam spin and target spin asymmetries measured by Hermes. We extract the real and imaginary par

  58. Harm Derksen, David Masser

    Let K be a field of positive characteristic. When V is a linear variety in K^n and G is a finitely generated subgroup of K^*, we show how to compute the intersection of V and G^n effectively using heights. We calculate all the estimates explicitly. A special case provides the effective solution of the S-unit equation in n variables.

  59. Mairi Sakellariadou

    Noncommutative spectral geometry succeeds in explaining the physics of the Standard Model of electroweak and strong interactions in all its details as determined by experimental data. Moreover, by construction the theory lives at very high energy scales, offering a natural framework to address early universe cosmological issues. After introducing the main el

  60. Terrence M. Adams, Andrew B. Nobel

    For any family of measurable sets in a probability space, we show that either (i) the family has infinite Vapnik-Chervonenkis (VC) dimension or (ii) for every epsilon > 0 there is a finite partition pi such the pi-boundary of each set has measure at most epsilon. Immediate corollaries include the fact that a family with finite VC dimension has finite bracket

  61. Jose Beltran Jimenez, Antonio L. Maroto

    In this work we consider the most general electromagnetic theory in curved space-time leading to linear second order differential equations, including non-minimal couplings to the space-time curvature. We assume the presence of a temporal electromagnetic background whose energy density plays the role of dark energy, as has been recently suggested. Imposing t

  62. K. Moraitis, A. Mastichiadis

    We study the expected variability patterns of blazars within the two-zone acceleration model putting special emphasis on flare shapes and spectral lags. We solve semi-analytically the kinetic equations which describe the particle evolution in the acceleration and radiation zone. We then perturb the solutions by introducing Lorentzian variations in its key pa

  63. A. Sinner, A. Sedrakyan, K. Ziegler

    We study the influence of lattice deformations on the optical conductivity of a two-dimensional electron gas. Lattice deformations are taken into account by introducing a non-abelian gauge field into the Eucledian action of two-dimensional Dirac electrons. This is in analogy to the introduction of the gravitation in the four-dimensional quantum field theory.

  64. Taylor L. Hughes, Emil Prodan, B. Andrei Bernevig

    We study translationally-invariant insulators with inversion symmetry that fall outside the established classification of topological insulators. These insulators are not required to have gapless boundary modes in the energy spectrum. However, they do exhibit protected modes in the entanglement spectrum localized on the cut between two entangled regions. The

  65. Roni Parshani, Celine Rozenblat, Daniele Ietri, Cesar Ducruet

    Recent studies have shown that a system composed from several randomly interdependent networks is extremely vulnerable to random failure. However, real interdependent networks are usually not randomly interdependent, rather a pair of dependent nodes are coupled according to some regularity which we coin inter-similarity. For example, we study a system compos

  66. Sergei Fedotov

    We propose two nonlinear random walk models which are suitable for the analysis of both chemotaxis and anomalous transport. We derive the balance equations for the population density for the case when the transition rate for a random walk depends on residence time, chemotactic substance and population density. We introduce the anomalous chemotactic sensitivi

  67. Sandor P. Fekete, Tom Kamphans, Nils Schweer

    We analyze the problem of packing squares in an online fashion: Given a semi-infinite strip of width 1 and an unknown sequence of squares of side length in [0,1] that arrive from above, one at a time. The objective is to pack these items as they arrive, minimizing the resulting height. Just like in the classical game of Tetris, each square must be moved alon

  68. Walid Saad, Zhu Han, Tamer Basar, Merouane Debbah

    Collaborative Spectrum Sensing (CSS) between secondary users (SUs) in cognitive networks exhibits an inherent tradeoff between minimizing the probability of missing the detection of the primary user (PU) and maintaining a reasonable false alarm probability (e.g., for maintaining a good spectrum utilization). In this paper, we study the impact of this tradeof

  69. Robert Hovden, Huolin L. Xin, David A. Muller

    Aberration-corrected scanning transmission electron microscopes (STEM) provide sub-angstrom lateral resolution; however, the large convergence angle greatly reduces the depth of field. For microscopes with a small depth of field, information outside of the focal plane quickly becomes blurred and less defined. It may not be possible to image some samples enti

  70. Walid Saad, Zhu Han, Tamer Basar, Merouane Debbah

    Autonomous wireless agents such as unmanned aerial vehicles or mobile base stations present a great potential for deployment in next-generation wireless networks. While current literature has been mainly focused on the use of agents within robotics or software applications, we propose a novel usage model for self-organizing agents suited to wireless networks

  71. Roni Parshani, Sergey V. Buldyrev, Shlomo Havlin

    Current network models assume one type of links to define the relations between the network entities. However, many real networks can only be correctly described using two different types of relations. Connectivity links that enable the nodes to function cooperatively as a network and dependency links that bind the failure of one network element to the failu

  72. B. Hackens, F. Martins, S. Faniel, C. A. Dutu

    In the Quantum Hall regime, near integer filling factors, electrons should only be transmitted through spatially-separated edge states. However, in mesoscopic systems, electronic transmission turns out to be more complex, giving rise to a large spectrum of magnetoresistance oscillations. To explain these observations, recent models put forward that, as edge

  73. W. Schmidt, C. Federrath

    We formulate and implement the Euler equations with SGS dynamics and provide numerical tests of an SGS turbulence energy model that predicts the turbulent pressure of unresolved velocity fluctuations and the rate of dissipation for highly compressible turbulence. We test closures for the turbulence energy cascade by filtering data from high-resolution simula

  74. Jon P. Fulbright, Rosemary F. G. Wyse, Gregory R. Ruchti, G. F. Gilmore

    Very metal-poor stars are of obvious importance for many problems in chemical evolution, star formation, and galaxy evolution. Finding complete samples of such stars which are also bright enough to allow high-precision individual analyses is of considerable interest. We demonstrate here that stars with iron abundances [Fe/H] < -2 dex, and down to below -4 de

  75. Michael Bon, Henri Orland

    We present TT2NE, a new algorithm to predict RNA secondary structures with pseudoknots. The method is based on a classification of RNA structures according to their topological genus. TT2NE guarantees to find the minimum free energy structure irrespectively of pseudoknot topology. This unique proficiency is obtained at the expense of the maximum length of se

  76. Abhik Ghosh, Somnath Bharadwaj, Sk. Saiyad Ali, Jayaram N. Chengalur

    We have analyzed 610 MHz GMRT observations towards detecting the redshifted 21-cm signal from z=1.32. The multi-frequency angular power spectrum C_l(Delta nu) is used to characterize the statistical properties of the background radiation across angular scales ~20&#34; to 10&#39;, and a frequency bandwidth of 7.5 MHz with resolution 125 kHz. The measured C_l(

  77. Thomas A. Witten, Nathan W. Krapf

    The binding of clusters of metal nanoparticles is partly electrostatic. We address difficulties in calculating the electrostatic energy when high charging energies limit the total charge to a single quantum, entailing unequal potentials on the particles. We show that the energy at small separation $h$ has a strong logarithmic dependence on $h$. We give a gen

  78. Martin Traizet

    We develop a theory of holomorphic differentials on a certain class of non-compact Riemann surfaces obtained by opening infinitely many nodes.

  79. Gabriel Navarro

    We make a first approach to the representation theory of the wedge product of coalgebras by means of the description of its valued Gabriel quiver. Then we define semiprime coalgebras and study its category of comodules by the use of localization techniques. In particular, we prove that, whether its Gabriel quiver is locally finite, any monomial semiprime fc-

  80. Valentin I. Zakharov

    We start with the QCD sum rules which are originally based on the idea that it is the power-like corrections to the parton model which are related to the confinement. The naive use of the Operator Product Expansion ensures that there is a &#39;gap&#39; in the powers of $Λ_{QCD}$ which miss the quadratic terms and start with the quartic term, proportional to

  81. Grigoris Panotopoulos

    The gravitino dark matter with neutralino NLSP hypothesis is investigated in the framework of NMSSM. We have considered both the thermal and non-thermal gravitino production mechanisms, and we have taken into account all the collider and cosmological constraints. The maximum allowed reheating temperature after inflation, as well as the maximum allowed gravit

  82. I. S. Bojicic, Q. A. Parker, M. D. Filipovic, D. J. Frew

    We present an updated and newly compiled radio-continuum data-base for MASH PNe detected in the extant large scale &#34;blind&#34; radio-continuum surveys (NVSS, SUMSS/MGPS-2 and PMN) and, for a small number of MASH PNe, observed and detected in targeted radio-continuum observations. We found radio counterparts for approximately 250 MASH PNe. In comparison w

  83. Gabor Szederkenyi, Katalin M. Hangos

    Reversibility, weak reversibility and deficiency, detailed and complex balancing are generally not &#34;encoded&#34; in the kinetic differential equations but they are realization properties that may imply local or even global asymptotic stability of the underlying reaction kinetic system when further conditions are also fulfilled. In this paper, efficient n

  84. Manoj K. Panda, Anurag Kumar

    Analytical models for IEEE 802.11-based WLANs are invariably based on approximations, such as the well-known \textit{decoupling approximation} proposed by Bianchi for modeling single cell WLANs consisting of saturated nodes. In this paper, we provide a new approach to model the situation when the nodes are not saturated. We study a State Dependent Attempt Ra

  85. Bruno Piccirillo, Vincenzo D&#39;Ambrosio, Sergei Slussarenko, Lorenzo Marrucci

    Exploiting electro-optic effects in liquid crystals, we achieved real-time control of the retardation of liquid- crystal-based $q$-plates through an externally applied voltage. The newly conceived electro-optic $q$-plates can be operated as electrically driven converters of photon spin into orbital angular momentum, enabling a variation of the orbital angula

  86. Andreas Arvanitoyeorgos, Ioannis Chrysikos, Yusuke Sakane

    We find the precise number of non-Kähler $Sp(n)$-invariant Einstein metrics on the generalized flag manifold $M=Sp(n)/(U(p)\times U(n-p))$ with $n\geq 3$ and $1\leq p\leq n-1$. We use an analysis on parametric systems of polynomial equations and we give some insight towards the study of such systems.

  87. Dan Lascu, Ion Coltescu

    This paper present the important role that random system with complete connections played in solving the Gauss problem associated to the regular continued fractions. Hence, using the ergodic behavior of homogeneous random system with complete connections, we will solve a Gauss - Kuzmin type theorem.

  88. E. Rigliaco, A. Natta, S. Randich, L. Testi

    This paper presents the results of an U band survey with FORS1/VLT of a large area in the sigma Orionis star-forming region. We combine the U-band photometry with literature data to compute accretion luminosity and mass accretion rates from the U-band excess emission for all objects (187) detected by Spitzer in the FORS1 field and classified by Hernandez et

  89. Ran El-Yaniv, Mordechai Nisenson

    Motivated by authentication, intrusion and spam detection applications we consider single-class classification (SCC) as a two-person game between the learner and an adversary. In this game the learner has a sample from a target distribution and the goal is to construct a classifier capable of distinguishing observations from the target distribution from obse

  90. Alessandro Giuliani, Vieri Mastropietro, Marcello Porta

    The exact vanishing of the interaction corrections to the zero temperature and zero frequency conductivity of graphene in the presence of weak short range interactions is rigorously established.

  91. Joaquin Luna-Torres, Carlos Orlando Ochoa C

    The introduction of the categorical notion of closure operators has unified various important notions and has led to interesting examples and applications in diverse areas of mathematics (see for example, Dikranjan and Tholen (\cite{DT})). For a topological space it is well-known that the associated closure and interior operators provide equivalent descripti

  92. Marco Zamparo, Antonio Trovato, Amos Maritan

    We propose an exactly solvable simplified statistical mechanical model for the thermodynamics of beta-amyloid aggregation, generalizing a well-studied model for protein folding. The monomer concentration is explicitly taken into account as well as a non trivial dependence on the microscopic degrees of freedom of the single peptide chain, both in the alpha-he

  93. Erin Mentuch, Roberto Abraham, Stefano Zibetti

    We have measured the near-infrared colors and the fluxes of individual pixels in 68 galaxies common to the Spitzer Infrared Nearby Galaxies Survey and the Large Galaxy Atlas Survey. Each galaxy was separated into regions of increasingly red near-infrared colors. In the absence of dust extinction and other non-stellar emission, stellar populations are shown t

  94. N. Clement, K. Nishiguchi, A. Fujiwara, D. Vuillaume

    Flicker or 1/f noise in metal-oxide-semiconductor field-effect transistors (MOSFETs) has been identified as the main source of noise at low frequency. It often originates from an ensemble of a huge number of charges trapping and detrapping. However, a deviation from the well-known model of 1/f noise is observed for nanoscale MOSFETs and a new model is requir

  95. S. I. Grachev, V. K. Dubrovich

    Within the framework of a flat cosmological model a propagation of an instantaneous burst of nonpolarized isotropic radiation is considered from the moment of its beginning at some initial redshift z0 to the moment of its registration now (at z=0). Thomson (Rayleigh) scattering by free electrons is considered as the only source of opacity. Spatial distributi

  96. Dafeng Zuo

    In this paper, we propose a two-component generalization of the generalized Hunter-Saxton equation obtained in \cite{BLG2008}. We will show that this equation is a bihamiltonian Euler equation, and also can be viewed as a bi-variational equation.

  97. L. C. Gallo, D. Grupe, N. Schartel, S. Komossa

    In March 2009 the well-studied quasar, PG 0844+349, was discovered with Swift to be in an X-ray weak state. A follow-up XMM-Newton observation several weeks later generated a good quality spectrum of the source, showing substantial curvature and spectral hardening. In combination with archival data at two previous epochs when the source was in a bright state

  98. L. G. Lukyanov, S. A. Gasanov

    Motions of stars in close binary systems with a conservative mass exchange are examined. It is shown that Paczynski-Huang model widely used now for obtaining the semi-major axis variation of a relative stars orbit is incorrect, because it brings about large mistakes. A new model suitable for elliptical orbits of stars is proposed. Both of reactive and attrac

  99. M. Muzychuk, I. Ponomarenko

    An association scheme is called quasi-thin if the valency of each its basic relation is one or two. A quasi-thin scheme is Kleinian if the thin residue of it forms a Klein group with respect to the relation product. It is proved that any Kleinian scheme arises from near-pencil on~$3$ points, or affine or projective plane of order~$2$. The main result is that

  100. N. Vandersickel, D. Dudal, O. Oliveira, S. P. Sorella

    Over the last years, lattice calculations in pure Yang-Mills gauge theory seem to have come more or less to a consensus. The ghost propagator is not enhanced and the gluon propagator is positivity violating, infrared suppressed and non-vanishing at zero momentum. From an analytical point of view, several groups are agreeing with these results. Among them, th