April 2009 arXiv papers — page 16

Joao L. Yun, Davide Elia, Pedro M. Palmeirim, Joana I. Gomes

We investigate the star-formation ocurring in the region towards IRAS07527-3446 in the molecular cloud [MAB97]250.63-3.63, in the far outer Galaxy. We report the discovery of a new young stellar cluster, and describe its properties and those of its parent molecular cloud. Near-infrared JHKS images were obtained with VLT/ISAAC, and millimetre line CO spectra

Sayan Bhattacharya, Vincent Conitzer, Kamesh Munagala, Lirong Xia

In this paper, we consider the problem of designing incentive compatible auctions for multiple (homogeneous) units of a good, when bidders have private valuations and private budget constraints. When only the valuations are private and the budgets are public, Dobzinski {\em et al} show that the {\em adaptive clinching} auction is the unique incentive-compati

Daniele Arcara, Aaron Bertram

Bridgeland stability conditions allow for a new generalization of Thaddeus pairs to surfaces and a new interpretation of Reider's theorem as a consequence of "Schur's lemma" for stable objects (Hom(E,F) = 0 if E,F are stable objects and the slope of E exceeds the slope of F). One improvement of Reider's theorem results (Proposition 3.8/Co

J. Lefebvre, M. Hilke, Z. Altounian

Since it was first observed about 40 years ago [1], the peak effect has been the subject of numerous research mainly impelled by the desire to determine its exact mechanisms. Despite these efforts, a consensus on this question has yet to be reached. Experimentally, the peak effect indicates a transition from a depinned vortex phase to a reentrant pinning pha

W. Trautmann, M. Chartier, Y. Leifels, R. C. Lemmon

The elliptic flow (squeeze-out) of neutrons, protons and light complex particles in reactions of neutron-rich systems at relativistic energies is proposed as an observable sensitive to the strength of the symmetry term in the equation of state at supra-normal densities. Preliminary results from a study of the existing FOPI/LAND data for 197Au + 197Au collisi

Kelley M. Hess, D. J. Pisano, Eric M. Wilcots, Jayaram N. Chengular

We present deep HI observations of the moderately inclined spiral galaxy, NGC 2997. The goal of these observations was to search for HI clouds in the vicinity of NGC 2997 analogous to the high velocity clouds of the Milky Way and gain insight into their origins. We find evidence for the presence of a galactic fountain as well as the accretion of intragalacti

Richard Miles, Thomas Ward

We consider asymptotic orbit-counting problems for certain expansive actions by commuting automorphisms of compact groups. A dichotomy is found between systems with asymptotically more periodic orbits than the topological entropy predicts, and those for which there is no excess of periodic orbits.

T. Hilger, B. Kampfer

Pseudo-scalar and scalar $D$ mesons are considered within the QCD sum rule approach. We present an analysis of the mass splitting of the pseudo-scalar D - D-bar mesons and the relation to QCD condensates. Weinberg type sum rules are derived for chiral partners which highlight the role of the chiral condensate.

Davide R. Campagnari, Hugo Reinhardt, Axel Weber

We study the Hamiltonian approach to Yang-Mills theory in Coulomb gauge in Rayleigh-Schroedinger perturbation theory. The static gluon and ghost propagator as well as the potential between static colour sources are calculated to one-loop order. Furthermore, the one-loop $β$-function is calculated from both the ghost-gluon vertex and the static potential and

O. Blanch Bigas, O. Deligny, K. Payet, V. Van Elewyck

The detection of Earth-skimming tau neutrinos has turned into a very promising strategy for the observation of UHE cosmic neutrinos. The sensitivity of this channel crucially depends on the parameters of the propagation of the tau neutrino (and the tau lepton) through the terrestrial crust, which governs the flux of emerging tau leptons that can be detected.

David Garofalo

The interaction of large scale magnetic fields with the event horizon of rotating black holes (the Blandford-Znajek [1977] mechanism) forms the basis for some models of the most relativistic jets. We explore a scenario in which the central inward "plunging" region of the accretion flow enhances the trapping of large scale poloidal field on the black

R. E. Skelton, P. A. Woudt, R. C. Kraan-Korteweg

A deep K_s-band photometric catalogue of galaxies at the core of the rich, nearby Norma cluster (ACO3627) is presented. The survey covers about 45 by 45 square arcmin (slightly less than 1/3 Abell radius), which corresponds to approx. 0.8 Mpc^2 at the adopted distance (v_cmb/H0) of 70 Mpc of this cluster. The survey is estimated to be complete to a magnitude

Abram L. Falk, Frank H. L. Koppens, Chun L. Yu, Kibum Kang

Photonic circuits can be much faster than their electronic counterparts, but they are difficult to miniaturize below the optical wavelength scale. Nanoscale photonic circuits based on surface plasmon polaritons (SPs) are a promising solution to this problem because they can localize light below the diffraction limit. However, there is a general tradeoff betw

A. Kizilersu, M. R. Pennington

In principle, calculation of a full Green's function in any field theory requires knowledge of the infinite set of multi-point Green's functions, unless one can find some way of truncating the corresponding Schwinger-Dyson equations. For the fermion and boson propagators in QED this requires an {\it ansatz} for the full three point vertex. Here we il

Claudia M. Haetinger, Luis Ghivelder, Jacob Schaf, Paulo Pureur

The static critical phenomenology near the Curie temperature of the re-entrant metallic alloys Au_0.81Fe_0.19, Ni_0.78Mn_0.22, Ni_0.79Mn_0.21 and amorphous a-Fe_0.98Zr_0.08 is studied using a variety of experimental techniques and methods of analysis. We have generally found that the values for the exponents alpha, beta, gamma and delta depart significantly

Christian Schnell

We establish a relationship between the graded quotients of a filtered holonomic D-module, their sheaf-theoretic duals, and the characteristic variety, in case the filtered D-module underlies a polarized Hodge module on a smooth algebraic variety. The proof is based on Saito's result that the associated graded module is Cohen-Macaulay, and on local duali

Biagio Lucini, Agostino Patella

In SU($N$) gauge theories with fermions in the fundamental or in a two-index (either symmetric or antisymmetric) representation formulated on a manifold with at least one compact dimension with non-trivial holonomy the discrete symmetries $C$, $P$ and $T$ are broken at small enough size of the compact direction(s) for certain values of $N$. We show that for

Tomonori Fukunaga

In this paper we give the stable classification of ordered, pointed, oriented multi-component curves on surfaces with minimal crossing number less than or equal to 2 such that any equivalent curve has no simply closed curves in its components. To do this, we use the theory of words and phrases which was introduced by V. Turaev. Indeed we give the homotopy cl

T. Duric, A. F. Ho, D . K. K. Lee

We study the weak-tunnelling limit for a system of cold 40K atoms trapped in a one-dimensional optical lattice close to an s-wave Feshbach resonance. We calculate the local spectrum for three atoms at one site of the lattice within a two-channel model. Our results indicate that, for this one-dimensional system, one- and two-channel models will differ close t

G. Domenech, F. Holik, L. Kniznik, D. Krause

Our aim in this paper is to show an example of the formalism we have developed to avoid the label-tensor-product-vector-space-formalism of quantum mechanics when dealing with indistinguishable quanta. States in this new vector space, that we call the Q-space, refer only to occupation numbers and permutation operators act as the identity operator on them, ref

G. A. Levin, P. N. Barnes, J. P. Rodriguez, J. A. Connors

We discuss the emergence of a spontaneous temperature and critical current spatial modulation in current-carrying high temperature superconducting wire. The modulation of the critical current along the wire on a scale of 3 - 10 mm forces a fraction of the transport current to crisscross the resistive interface between the superconducting film and normal meta

Philippe Brax, Carsten van de Bruck, Jerome Martin, Anne-Christine Davis

We examine the embedding of dark energy in high energy models based upon supergravity and extend the usual phenomenological setting comprising an observable sector and a hidden supersymmetry breaking sector by including a third sector leading to the acceleration of the expansion of the universe. We find that gravitational constraints on the non-existence of

Boaz Tsaban

Contents: 1. Editor's note 2. Research announcements 2.1. Pseudocompact group topologies with no infinite compact subsets 2.2. Selective coideals on (FIN[1]k) 2.3. Entire functions mapping uncountable dense sets of reals onto each other monotonically 2.4. Effective refining of Borel coverings 2.5. Symmetry and colorings: Some results and open problems 2.

Pierre Collet, Servet Martinez, Sylvie Méléard, Jaime San Martin

We study the probabilistic evolution of a birth and death continuous time measure-valued process with mutations and ecological interactions. The individuals are characterized by (phenotypic) traits that take values in a compact metric space. Each individual can die or generate a new individual. The birth and death rates may depend on the environment through

M. E. Gusakov, E. M. Kantor, P. Haensel

We calculate the relativistic entrainment matrix Y_ik at zero temperature for nucleon-hyperon mixture composed of neutrons, protons, Lambda and Sigma^- hyperons, as well as of electrons and muons. This matrix is analogous to the entrainment matrix (also termed mass-density matrix or Andreev-Bashkin matrix) of non-relativistic theory. It is an important ingre

ZEUS Collaboration

The scaled momentum distributions of charged particles in jets have been measured for dijet photoproduction with the ZEUS detector at HERA using an integrated luminosity of 359 pb-1. The distributions are compared to predictions based on perturbative QCD carried out in the framework of the modified leading-logarithmic approximation (MLLA) and assuming local

Miguel Ángel Marco-Buzunariz, Jorge Martín-Morales

Let $Q\in \K[x_1,...,x_n] = S$ be a homogeneous polynomial of degree $d$. The freeness of the logarithmic derivation module, $D(Q)$, and of its natural generalizations, has been widely studied. In the free case, $D(Q) \simeq \bigoplus_{i=1}^n S(-d_i)$ where the $d_i$'s are the exponents of the module; and as a direct consequence of the Saito-Ziegler crit

R. Mittal, M. Zbiri, S. Rols, Y. Su

We report detailed measurements of composition as well as temperature dependence of the phonon density-of-states in a new series of FeAs compounds with composition CaFe1\_{1-x}Co\_{x}AsF (x = 0, 0.06, 0.12). The composition as well as temperature dependence of phonon spectra for CaFe\_{1-x}Co\_{x}AsF (x = 0, 0.06, 0.12) compounds have been measured using tim

M. Eshaghi Gordji, N. Ghobadipour

In this paper, we establish the Hyers--Ulam--Rassias stability of ring homomorphisms and ring derivations on fuzzy Banach algebras.

M. Jouravlev, Kwang S. Kim

For the study of molecular spin junctions, we take into account two types of couplings between the molecule and the metal leads: (i) electron transfer that gives rise to net current in the biased junction and (ii) energy transfer between the molecule and the leads. Using a rotating wave approximation in the Heisenberg representation, we derive a set of diffe

M. Eshaghi Gordji, A. Ebadian, M. B. Ghaemi, J. Shokri

In this paper, we introduce an iterative numerical method to solve systems of nonlinear equations. The third-order convergence of this method is analyzed. Several examples are given to illustrate the efficiency of the proposed method.

A. Akylas, I. Georgantopoulos

We present XMM-Newton spectral analysis of all 38 Seyfert galaxies from the Palomar spectroscopic sample of galaxies. These are found at distances of up to 67 Mpc and cover the absorbed 2-10 keV luminosity range ~10^38-10^43 ergs/s. Our aim is to determine the distribution of the X-ray absorption in the local Universe. Three of these are Compton-thick with c

Praveen Sivadasan, P Sojan Lal

Software obfuscation or obscuring a software is an approach to defeat the practice of reverse engineering a software for using its functionality illegally in the development of another software. Java applications are more amenable to reverse engineering and re-engineering attacks through methods such as decompilation because Java class files store the progra

Sh. Najafzadeh, M. Eshaghi Gordji, A. Ebadian

By considering a fixed point in unit disk $Δ$, a new class of univalent convex functions is defined. Coefficient inequalities, integral operator and extreme points of this class are obtained.

Federico Bonelli, Nicola Manini, Emiliano Cadelano, Luciano Colombo

Using a tight-binding atomistic simulation, we simulate the recent atomic-force microscopy experiments probing the slipperiness of graphene flakes made slide against a graphite surface. Compared to previous theoretical models, where the flake was assumed to be geometrically perfect and rigid, while the substrate is represented by a static periodic potential,

D. S. Golubev, M. S. Kalenkov, A. D. Zaikin

We formulate a microscopic theory of non-local electron transport in three-terminal diffusive normal-superconducting-normal (NSN) structures with arbitrary interface transmissions. At low energies $\varepsilon$ we predict strong enhancement of non-local spectral conductance $g_{12} \propto 1/\varepsilon$ due to quantum interference of electrons in disordered

Wenchang Chu, Chenying Wang

The partial sums of two quartic basic hypergeometric series are investigated by means of the modified Abel lemma on summation by parts. Several summation and transformation formulae are consequently established.

Assaf Libman

We construct an analogue of the normaliser decomposition for p-local finite groups (S,F,L) with respect to collections of F-centric subgroups and collections of elementary abelian subgroups of S. This enables us to describe the classifying space of a p-local finite group, before p-completion, as the homotopy colimit of a diagram of classifying spaces of fini

D. K. Sunko

The construction of the Zhang-Rice singlet is revisited in the light of recent understanding of high-temperature superconductors at optimal doping. A minimal local model is derived which contains the physical regime found relevant for ARPES experiments, characterized by significant direct oxygen-oxygen hopping. For the values of orbital parameters indicated

Leonid G. Fel, Jacob Bear

The coefficients of dispersion, D_{ij}, and the dispersivity, a_{ijkl}, appear in the expression for the flux of a solute in saturated flow through porous media. We present a detailed analysis of these tensors in an axially symmetric porous medium and show that in such a medium, the dispersivity is governed by 6 independent moduli. We present also the constr

L. A. Alexeyeva

The biquaternion approach is developed for building of the equations of the inter-action of different charges and currents and generated Electro-GravyMagnetic fields. The field analogues of three Newton's laws are offered free and interacting charge-currents, as well as total field of interaction. An invariance of the equations for one EGM-field model at

Bhupendra Gupta

It is a correction paper on "P.J. Wan and C.W. Yi, "Coverage by Randomly Deployed Wireless Sensor Networks", IEEE Transaction On Information Theory, vol.52, No.6, June 2006." In the above paper, Lemma (4), on page 2659 play the key role for deriving the main results in the paper. The statement as well as the proof of Lemma (4), page $2659,$ i

A. V. Derbin, S. V. Bakhlanov, A. I. Egorov, I. A. Mitropolsky

The search for resonant absorption of the Primakoff solar axions by $^{169}$Tm nuclei have been performed. Such an absorption should lead to the excitation of low-lying nuclear energy level: $A+^{169}$Tm $\to ^{169}$Tm$^*$ $\to ^{169}$Tm$ + γ$ (8.41 keV). The Si(Li) detector and $^{169}$Tm target placed inside the low-background setup were used for that purp

Laurent Chemin, Olivier Hernandez

We report on an estimate of the bar pattern speed Omega_p for the low surface brightness spiral galaxy UGC 628. We applied the Tremaine-Weinberg method to high resolution Halpha velocity and integrated emission maps of this dark matter dominated galaxy. Observations were made at the CFHT using the optical Fabry-Perot interferometer, FaNTOmM. The Tremaine-Wei

Christian Wolf

We combine in a single framework the two complementary benefits of chi^2-template fits and empirical training sets used e.g. in neural nets: chi^2 is more reliable when its probability density functions (PDFs) are inspected for multiple peaks, while empirical training is more accurate when calibration and priors of query data and training set match. We prese

Renat Yulmetyev, Ramil Khusnutdinoff, Timur Tezel, Yildiz Iravul

Analytically and quantitatively we reveal that the GLE equation, based on a memory function approach, in which memory functions and information measures of statistical memory play fundamental role in determining the thin details of the stochastic behavior of seismic systems, naturally conduces to a description of seismic phenomena in terms of strong and weak

Kenta Fuji, Takao Suzuki

We study the Drinfeld-Sokolov hierarchies of type A_n^{(1)} associated with the regular conjugacy classes of W(A_n). A class of fourth order Painleve systems is derived from them by similarity reductions.

Julia Böttcher, Jan Hladky, Diana Piguet

We prove that for all epsilon>0 there are c>0 and n_0 such that for all n>n_0 the following holds. For any two-colouring of the edges of $K_{n,n,n}$ one colour contains copies of all trees T of order t<(3-epsilon)n/2 and with maximum degree at most n^c. This confirms a conjecture of Schelp.

Solen Balman

We detect dipping activity/modulations in the light curve of the four LMXBs in the 3--10 keV and 20--40 keV energy ranges. The spectral parameters derived from the fits to the INTEGRAL data are consistent with hot coronal structures in these systems where we find a range of plasma temperatures 3.0--224.9 keV. The unabsorbed X-ray to soft Gamma-ray flux betwe

I. Cahit

In this paper we have given an algorithmic proof of an long standing Barnette&#39;s conjecture (1969) that every 3-connected bipartite cubic planar graph is hamiltonian. Our method is quite different than the known approaches and it rely on the operation of opening disjoint chambers, bu using spiral-chain like movement of the outer-cycle elastic-sticky edges

William Crawley-Boevey

We introduce a notion of a connection on a coherent sheaf on a weighted projective line (in the sense of Geigle and Lenzing). Using a theorem of Huebner and Lenzing we show, under a mild hypothesis, that if one considers coherent sheaves equipped with such a connection, and one passes to the perpendicular category to a nonzero vector bundle without self-exte

S. Colafrancesco, P. Marchegiani

(Abridged) High-E electrons produce Hard X-Ray (HXR) emission in galaxy clusters by via Inverse Compton Scattering (ICS) of CMB photons. We derive the ICS HXR emission of Ophiuchus under various scenarios: primary cosmic ray model, secondary cosmic rays model and neutralino DM annihilation scenario. We further discuss the predictions of the Warming Ray model

Tapan Nayak, Bikash Sinha

The major aim of nucleus-nucleus collisions at the LHC is to study the physics of strongly interacting matter and the quark gluon plasma (QGP), formed in extreme conditions of temperature and energy density. We give a brief overview of the experimental program and discuss the signatures and observables for a detailed study of QGP matter.

Kazuo Hiroi, Daisaku Nogami, Yoshihiro Ueda, Yuuki Moritani

We carried out an international spectroscopic observation campaign of the dwarf nova GW Librae (GW Lib) during the 2007 superoutburst. Our observation period covered the rising phase of the superoutburst, maximum, slowly decaying phase (plateau), and long fading tail after the rapid decline from the plateau. The spectral features dramatically changed during

O. O. Vaneeva, R. O. Popovych, C. Sophocleous

Reduction operators (called often nonclassical symmetries) of variable coefficient semilinear reaction-diffusion equations with power nonlinearity $f(x)u_t=(g(x)u_x)_x+h(x)u^m$ ($m\neq0,1,2$) are investigated using the algorithm suggested in [O.O. Vaneeva, R.O. Popovych and C. Sophocleous, Acta Appl. Math., 2009, V.106, 1-46; arXiv:0708.3457].

Sunder Lal, Vandani Verma

Braids groups provide an alternative to number theoretic public cryptography and can be implemented quite efficiently. The paper proposes five signature schemes: Proxy Signature, Designated Verifier, Bi-Designated Verifier, Designated Verifier Proxy Signature And Bi-Designated Verifier Proxy Signature scheme based on braid groups. We also discuss the securit

S. Pellegrini, L. Ciotti, J. P. Ostriker

The centers of elliptical galaxies host supermassive black holes that significantly affect the surrounding interstellar medium through feedback resulting from the accretion process. The evolution of this gas and of the nuclear emission during the galaxies&#39; lifetime has been studied recently with high-resolution hydrodynamical simulations. These included

Sunder Lal, Vandani Verma

This paper presents a new identity based strong designated verifier parallel multi-proxy signature scheme. Multi-Proxy signatures allow the original signer to delegate his signing power to a group of proxy signers. In our scheme, the designated verifier can only validate proxy signatures created by a group of proxy signer.

A. M. Cherepashchuk, R. A. Sunyaev, K. A. Postnov, E. A. Antokhina

The analysis of hard X-ray INTEGRAL observations (2003-2008) of superaccreting galactic microquasar SS433 at precessional phases of the source with the maximum disk opening angle is carried out. It is found that the shape and width of the primary X-ray eclipse is strongly variable suggesting additional absorption in dense stellar wind and gas outflows from t

A. Budzanowski, A. Chatterjee, P. Hawranek, R. Jahn

Inclusive measurements of pion production in proton--proton collisions in the forward direction were undertaken at 400 and 600 MeV at COSY using the Big Karl spectrograph. The high resolution in the $π^+$ momentum ensured that there was an unambiguous separation of the $pp\to π^+d/π^+pn$ channels. Using these and earlier data, the ratio of the production cro

Jürgen Stoll, Jadran Vrabec, Hans Hasse

Results of a systematic investigation of the vapour-liquid equilibria of 38 individual two-centre Lennard-Jones plus axial pointdipole model fluids (2CLJD) are reported over a range of reduced dipolar momentum 0 $\le μ^{*2} \le$ 20 and of reduced elongation 0 $\le$ L* $\le$ 1.0. Temperatures investigated are from about 55 % to about 95 % of the critical temp

Alexander Lubotzky

Finite simple groups of Lie type as expanders

F. Aharonian

Detection of a gamma-ray source above 300 GeV is reported, confirming the unidentified source MGRO J1908+06, discovered by the Milagro collaboration at a median energy of 20 TeV. The source was observed during 27 h as part of the extension of the H.E.S.S. Galactic plane survey to longitudes >30degr. HESS J1908+063 is detected at a significance level of 10.9

N. Mohr

Within the mSUGRA model, the observability of the decay of the next to lightest neutralino into leptons and the lightest neutralino has been studied using a full simulation of the CMS detector. The final state signature consists of two opposite sign leptons, several hard jets and missing transverse energy. The expected precision of the measurement of the dil

Roberto Casadio, Remo Garattini, Fabio Scardigli

We review the General Relativistic model of a (quasi) point-like particle represented by a massive shell of neutral matter which has vanishing total energy in the small-volume limit. We then show that, by assuming a Generalised Uncertainty Principle, which implies the existence of a minimum length of the order of the Planck scale, the total energy instead re

C. R. Dean, B. A. Piot, G. Gervais, L. N. Pfeiffer

Electrically detected nuclear magnetic resonance was studied in detail in a two-dimensional electron gas as a function of current bias and temperature. We show that applying a relatively modest dc-current bias, I_dc ~ 0.5 microAmps, can induce a re-entrant and even enhanced nuclear spin signal compared with the signal obtained under similar thermal equilibri

Brian M. Andersen, Olav F. Syljuasen, Per Hedegard

We present an explanation of the dynamical in-gap spin mode in LSCO induced by an applied magnetic field H as recently observed by J. Chang et al. Our model consists of a phenomenological spin-only Hamiltonian, and the softening of the spin mode is caused by vortex pinning of dynamical stripe fluctuations which we model by a local ordering of the exchange in

V. Krishan, S. Masuda

The lower solar atmosphere consists of partially ionized turbulent plasmas harbouring velocity field, magnetic field and current density fluctuations. The correlations amongst these small scale fluctuations give rise to large scale flows and magnetic fields which decisively affect all transport processes. The three fluid system consisting of electrons, ions

J. Merino, R. H. McKenzie, B. J. Powell

We report a detailed study of a model Hamiltonian which exhibits a rich interplay of geometrical spin frustration, strong electronic correlations, and charge ordering. The character of the insulating phase depends on the magnitude of Delta/|t| and on the sign of t. We find a Mott insulator for Delta >> U >> |t|; a charge transfer insulator for U >> Δ>> |t|;

Stephan M. Wehrli

We prove that Khovanov homology and Lee homology with coefficients in $\mathbb{F}_2$ are invariant under component-preserving link mutations.

Jean Ludwig, Lyudmila Turowska

We describe the C*-algebras of the Heisenberg group H_n, n\geq 1, and the thread-like Lie group G_N, N\geq 3, in terms of C*-algebras of operator fields.

Masanori Morishita

This is an expository article of our work on analogies between knot theory and algebraic number theory. We shall discuss foundational analogies between knots and primes, 3-manifolds and number rings mainly from the group-theoretic point of view.

Yuichi Otsuka, Hitoshi Seo, Yukitoshi Motome, Takeo Kato

We investigate ground state properties of a quasi-one-dimensional electron-lattice coupled model for quarter-filled molecular conductors. The effective one-dimensional extended Hubbard model coupled to adiabatic lattice degree of freedom is derived by the inter-chain mean-field approximation and solved by Lanczos exact diagonalization method. We find that th

Marie-Line Chabanol, Jean Duchon

We consider the one dimensional Burgers equation forced by a brownian in space and white noise in time process $\partial_t u + u \partial_x u = f(x,t)$, with $2E(f(x,t)f(y,s)) = (|x|+|y|-|x-y|)δ(t-s)$ and we show that there are Levy processes solutions, for which we give the evolution equation of the characteristic exponent. In particular we give the explici

M. Andrecut

Computational time reversal imaging can be used to locate the position of multiple scatterers in a known background medium. Here, we discuss a sparse approximation method for computational time-reversal imaging. The method is formulated entirely in the frequency domain, and besides imaging it can also be used for denoising, and to determine the magnitude of

Federico Ricci-Tersenghi, Guilhem Semerjian

We introduce a version of the cavity method for diluted mean-field spin models that allows the computation of thermodynamic quantities similar to the Franz-Parisi quenched potential in sparse random graph models. This method is developed in the particular case of partially decimated random constraint satisfaction problems. This allows to develop a theoretica

V. Zhakhovskii, K. Nishihara, M. Abe

Molecular Dynamic (MD) approach is applied to study the converging cylindrical shock waves in a dense Lennard-Jones (LJ) fluid. MD method is based on tracking of the atom motions and hence it has an fundamental advantages over hydrodynamic methods which assumes shocks as a structureless discontinuity and requires an equation of state. Due to the small thickn

Jan M. Tomczak, Silke Biermann

The aim of the present paper is to present a versatile scheme for the computation of optical properties of solids, with particular emphasis on realistic many-body calculations for correlated materials. Geared at the use with localized basis sets, we extend the commonly known lattice &#34;Peierls substitution&#34; approach to the case of multi-atomic unit cel

C. Chong, D. E. Pelinovsky

Using a variational approximation we study discrete solitons of a nonlinear Schroedinger lattice with a cubic-quintic nonlinearity. Using an ansatz with six parameters we are able to approximate bifurcations of asymmetric solutions connecting site-centered and bond-centered solutions and resulting in the exchange of their stability. We show that the numerica

Norbert S. Schulz, Glenn Allen, Mark W. Bautz, Claude C. Canizares

Low-mass pre-main sequence (PMS) stars are strong and variable X-ray emitters, as has been well established by EINSTEIN and ROSAT observatories. It was originally believed that this emission was of thermal nature and primarily originated from coronal activity (magnetically confined loops, in analogy with Solar activity) on contracting young stars. Broadband

Céline Hadziioannou, Eric Larose, Olivier Coutant, Philippe Roux

Previous studies have shown that small changes can be monitored in a scattering medium by observing phase shifts in the coda. Passive monitoring of weak changes through ambient noise correlation has already been applied to seismology, acoustics and engineering. Usually, this is done under the assumption that a properly reconstructed Green function as well as

Norbert S. Schulz, Glenn Allen, Mark W. Bautz, Claude C. Canizares

Understanding the origins and distribution of matter in the Universe is one of the most important quests in physics and astronomy. Themes range from astro-particle physics to chemical evolution in the Galaxy to cosmic nucleosynthesis and chemistry in an anticipation of a full account of matter in the Universe. Studies of chemical evolution in the early Unive

B. H. C. Emonts, C. N. Tadhunter, R. Morganti, T. A. Oosterloo

We present new observational results that conclude that the nearby radio galaxy B2 0722+30 is one of the very few known disc galaxies in the low-redshift Universe that host a classical double-lobed radio source. In this paper we use HI observations, deep optical imaging, stellar population synthesis modelling and emission-line diagnostics to study the host g

C. Michoski, J. A. Evans, P. G. Schmitz, A. Vasseur

We present a solution to the conservation form (Eulerian form) of the quantum hydrodynamic equations which arise in chemical dynamics by implementing a mixed/discontinuous Galerkin (MDG) finite element numerical scheme. We show that this methodology is stable, showing good accuracy and a remarkable scale invariance in its solution space. In addition the MDG

M. Hossain Ali, M. Khayrul Hasan

We investigate the general relativistic magnetohydrodynamic (GRMHD) equations for cold plasma around the Reissner-Nordström black hole. Applying 3+1 spacetime split we linearize the perturbed equations for non-magnetized/magnetized plasma in both rotating and non-rotating background. By Fourier analyze we then derive dispersion relations and investigate the

Mircea Voineagu

We use the cylindrical homomorphism and a geometric construction introduced by J. Lewis to study the Lawson homology groups of certain hypersurfaces $X\subset \mathbb{P}^{n+1}$ of degree $d\leq n+1$. As an application, we compute the rational semi-topological K-theory of a generic cubic of dimension 5, 6 and 8 and, using the Bloch-Kato conjecture, we prove S

Takeshi Matsumura, Takumi Yonemura, Keisuke Kunimori, Masafumi Sera

CeB6, a typical Gamma_8-quartet system, exhibits a mysterious antiferroquadrupolar ordered phase in magnetic fields, which is considered as originating from the T_{xyz}-type magnetic octupole moment induced by the field. By resonant x-ray diffraction in magnetic fields, we have verified that the T_{xyz}-type octupole is indeed induced in the 4f-orbital of Ce

Zhiwei Yun

We prove three new results about the global Springer action defined in \cite{GSI}. The first one determines the support of the perverse cohomology sheaves of the parabolic Hitchin complex, which serves as a technical tool for the next results. The second one (the Endoscopic Decomposition Theorem) links certain direct summands of the parabolic Hitchin complex

Zhiwei Yun

We construct an action of the graded double affine Hecke algebra (DAHA) on the parabolic Hitchin complex, extending the affine Weyl group action constructed in \cite{GSI}. In particular, we get representations of the degenerate DAHA on the cohomology of parabolic Hitchin fibers. We also generalize our construction to {\em parahoric} versions of Hitchin stack

J. Fukue

We examine the behavior of the variable Eddington factor for a relativistically moving radiative flow in the vertical direction. We adopt the &#34;one-tau photo-oval&#34; approximation in the comoving frame. Namely, the comoving observer sees radiation coming from a closed surface where the optical depth measured from the observer is unity; such a surface is

Stephen Becker, Jerome Bobin, Emmanuel Candes

Accurate signal recovery or image reconstruction from indirect and possibly undersampled data is a topic of considerable interest; for example, the literature in the recent field of compressed sensing is already quite immense. Inspired by recent breakthroughs in the development of novel first-order methods in convex optimization, most notably Nesterov&#39;s

Mark Daley, Michael Domaratzki, Kai Salomaa

A language $L$ is the orthogonal catenation of languages $L_1$ and $L_2$ if every word of $L$ can be written in a unique way as a catenation of a word in $L_1$ and a word in $L_2$. We establish a tight bound for the state complexity of orthogonal catenation of regular languages. The bound is smaller than the bound for arbitrary catenation.

Cheng Hui Ren

This paper expands and improves on the general Sieve method. This expaned and improved Sieve is applied to Goldbach&#39;s problem. A new estimate of the exception set in Goldbach&#39;s number E(X), an improved lower bound D_{1,2}(N) and upper bound D(N) are proposed. The proposed values are: |E(X)|<= X^{0.702+e}, D_{1,2}(N)>= 2.27C(N)/ln^{2}(N), D(N) <= 6.91

R. Benguria, M. Loewe, R. A. Santos

In this letter we discuss the influence of a U(1) chemical potential $μ$ on the existence of Gribov copies in a U(1) theory at finite temperature $T$. We show that the chemical potential conspires against the existence of Gribov copies in the sense that it restricts the space of solutions of the consistency equation for the gauge parameter. Explicit solution

I. Matsuyama, D. Johnstone, D. Hollenbach

We present a model for the dispersal of protoplanetary disks by winds from either the central star or the inner disk. These winds obliquely strike the flaring disk surface and strip away disk material by entraining it in an outward radial-moving flow at the wind-disk interface which lies several disk scale heights above the mid-plane. The disk dispersal time

Yuri A. Rylov

Contemporary geometers do not acknowledge nonaxomatizable geometries. This fact means that our knowledge of geometry is poor. A perfect knowledge of geometry is important for &#34;consumers of geometry&#34; (physicists dealing with geometry of microcosm), because poor knowledge of geometry forces physicists to refuse from the orthodox geometrical paradigm an

H. Baumgardt, P. Cote, M. Hilker, M. Rejkuba

Precise radial velocity measurements from HIRES on the Keck I telescope are presented for 40 stars in the outer halo globular cluster NGC 2419. These data are used to probe the cluster&#39;s stellar mass function and search for the presence of dark matter in this cluster. NGC 2419 is one of the best Galactic globular clusters for such a study due to its long

Ari Stern, Eitan Grinspun

In this paper, we derive a variational integrator for certain highly oscillatory problems in mechanics. To do this, we take a new approach to the splitting of fast and slow potential forces: rather than splitting these forces at the level of the differential equations or the Hamiltonian, we split the two potentials with respect to the Lagrangian action integ

Liviu Ornea, Misha Verbitsky

Locally conformally Kahler (LCK) manifolds with potential are those which admit a Kahler covering with a proper, automorphic Kaehler potential. Existence of a potential can be characterized cohomologically as a vanishing of a certain cohomology class, called the Bott-Chern class. Compact LCK manifolds with potential are stable at small deformations and admit

A. M. Gago, H. Minakata, H. Nunokawa, S. Uchinami

In neutrino oscillation with non-standard interactions (NSI) the system is enriched with CP violation caused by phases due to NSI in addition to the standard lepton Kobayashi-Maskawa phase \delta. In this paper we show that it is possible to disentangle the two CP violating effects by measurement of muon neutrino appearance by a near-far two detector setting