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Sourav Bhattacharya; Amitabha Lahiri
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We present a nonperturbative proof of the no hair theorems corresponding to scalar and Proca fields for stationary axisymmetric de Sitter black hole spacetimes. Our method also applies to asymptotically flat and under a reasonable assumption, to asymptotically antide Sitter spacetimes.
Source: http://arxiv.org/abs/1102.0053v2
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ANTARES collaboration; J. A. Aguilar; I. Al Samarai; A. Albert; M. Andre; M. Anghinolfi; G. Anton; S. Anvar; M. Ardid; A. C. Assis Jesus; T. Astraatmadja; JJ. Aubert; R. Auer; B. Baret; S. Basa; M. Bazzotti; V. Bertin; S. Biagi; C. Bigongiari; C. Bogazzi; M. BouCabo; M. C. Bouwhuis; A. M. Brown; J. Brunner; J. Busto; F. Camarena; A. Capone; C. Carloganu; G. Carminati; J. Carr; S. Cecchini; Ph. Charvis; T. Chiarusi; M. Circella; R. Coniglione; H. Costantini; N. Cottini; P. Coyle; C. Curtil; M. P. Decowski; I. Dekeyser; A. Deschamps; C. Distefano; C. Donzaud; D. Dornic; Q. Dorosti; D. Drouhin; T. Eberl; U. Emanuele; JP. Ernenwein; S. Escoffier; F. Fehr; V. Flaminio; U. Fritsch; JL. Fuda; S. Galata; P. Gay; G. Giacomelli; J. P. GomezGonzalez; K. Graf; G. Guillard; G. Halladjian; G. Hallewell; H. van Haren; A. J. Heijboer; Y. Hello; J. J. HernandezRey; B. Herold; J. HÃ¶ÃŸl; C. C. Hsu; M. de Jong; M. Kadler; N. KalantarNayestanaki; O. Kalekin; A. Kappes; U. Katz; P. Kooijman; C. Kopper; A. Kouchner; V. Kulikovskiy; R. Lahmann; P. Lamare; G. Larosa; D. Lefevre; G. Lim; D. Lo Presti; H. Loehner; S. Loucatos; F. Lucarelli; S. Mangano; M. Marcelin; A. Margiotta; J. A. MartinezMora; A. Mazure; A. Meli; T. Montaruli; M. Morganti; L. Moscoso; H. Motz; C. Naumann; M. Neff; D. Palioselitis; G. E. Pavalas; P. Payre; J. Petrovic; N. PicotClemente; C. Picq; V. Popa; T. Pradier; E. Presani; C. Racca; C. Reed; G. Riccobene; C. Richardt; R. Richter; A. Rostovtsev; M. Rujoiu; G. V. Russo; F. Salesa; P. Sapienza; F. SchÃ¶ck; JP. Schuller; R. Shanidze; F. Simeone; A. Spiess; M. Spurio; J. J. M. Steijger; Th. Stolarczyk; M. Taiuti; C. Tamburini; L. Tasca; S. Toscano; B. Vallage; V. Van Elewyck; G. Vannoni; M. Vecchi; P. Vernin; G. Wijnker; E. de Wolf; H. Yepes; D. Zaborov; J. D. Zornoza; J. Zuniga
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An algorithm is presented, that provides a fast and robust reconstruction of neutrino induced upwardgoing muons and a discrimination of these events from downwardgoing atmospheric muon background in data collected by the ANTARES neutrino telescope. The algorithm consists of a hit merging and hit selection procedure followed by fitting steps for a track hypothesis and a pointlike light source. It is particularly wellsuited for real time applications such as online monitoring and fast...
Source: http://arxiv.org/abs/1105.4116v1
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Dirk Pauly; Sergey Repin
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This paper is concerned with the derivation of computable and guaranteed upper bounds of the difference between the exact and the approximate solution of an exterior domain boundary value problem for a linear elliptic equation. Our analysis is based upon purely functional argumentation and does not attract specific properties of an approximation method. Therefore, the estimates derived in the paper at hand are applicable to any approximate solution that belongs to the corresponding energy...
Source: http://arxiv.org/abs/1105.4101v1
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Akiyuki Tokuno; Thierry Giamarchi
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The response of cold atom gases to small periodic phase modulation of an optical lattice is discussed. For bosonic gases, the energy absorption rate is given, within linear response theory, by imaginary part of the current correlation function. For fermionic gases in a strong lattice potential, the same correlation function can be probed via the production rate double occupancy. The phase modulation gives thus direct access to the conductivity of the system, as function of the modulation...
Source: http://arxiv.org/abs/1101.2469v2
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M. Lepers; V. ZehnlÃ©; J. C. Garreau
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In this work we apply the formalism developed in [M. Lepers \emph{et al}., Phys. Rev. A \textbf{77}, 043628 (2008)] to different initial conditions corresponding to systems usually met in reallife experiments, and calculate the observable quantities that can be used to characterize the dynamics of the system. The position space point of view allows highly intuitive pictures of the physics at play.
Source: http://arxiv.org/abs/1009.5892v2
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Victor Grigoriev; Fabio Biancalana
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We consider a nonlinear microcavity separating a waveguide channel into two parts so as the coupling between them is possible only due to the resonant properties of the microcavity. We provide a rigorous derivation of the equations used in the phenomenological coupled mode theory for such systems. This allows us to find the explicit formulas for all fitting parameters such as decay rates, coupling coefficients and characteristic intensities in terms of the mode profiles. The advantages of using...
Source: http://arxiv.org/abs/1105.4071v1
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V. Balasubramanian; A. Bernamonti; J. de Boer; N. Copland; B. Craps; E. KeskiVakkuri; B. MÃ¼ller; A. SchÃ¤fer; M. Shigemori; W. Staessens
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Using the AdS/CFT correspondence, we probe the scaledependence of thermalization in strongly coupled field theories following a quench via saddlepoint calculations of 2point functions, Wilson loops and entanglement entropy in $d=2,3,4$. For homogeneous initial conditions, the entanglement entropy thermalizes slowest, and sets a timescale for equilibration that saturates a causality bound. The growth rate of entanglement entropy density is nearly volumeindependent for small volumes, but slows...
Source: http://arxiv.org/abs/1012.4753v3
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Sugata Kaviraj; Kevin Schawinski; Joseph Silk; Stanislav S. Shabala
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Recent work indicates that starforming earlytype galaxies (ETGs) residing in the blue cloud migrate rapidly to the red sequence within around a Gyr, passing through several phases of increasingly strong AGN activity in the process (Schawinski et al. 2007, MNRAS, 382, 1415; S07 hereafter). We show that natural depletion of the gas reservoir through star formation (i.e. in the absence of any feedback from the AGN) induces a bluetored reddening rate that is several factors lower than that...
Source: http://arxiv.org/abs/1008.1583v2
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Smarajit Karmakar; Itamar Procaccia
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The dramatic slowing down associated with the glass transition cannot be fully understood without an associated static length that is expected to increase rapidly as the temperature is reduced. The search for such a length was long and arduous, without a universally accepted candidate at hand. Recently a natural such length $\xi_s$ was proposed, stemming from a crossover between plastic and elastic mechanical responses of the material. In this Letter we show that supercooled liquids in which...
Source: http://arxiv.org/abs/1105.4053v1
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Rikard Enberg; Roman Pasechnik
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We propose central exclusive production of a charged Higgs boson in association with a W boson as a possible signature of certain types of extended Higgs sectors. We calculate the cross section and find that the rate at the LHC could be large enough to allow observation in some models with two Higgs doublets, where the charged Higgs and at least one of the neutral scalars can be light enough. We use the twoHiggs doublet model as a prototype and consider two distinct regions of parameter space,...
Source: http://arxiv.org/abs/1104.0889v2
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Lilia Anguelova; Peter Suranyi; L. C. Rohana Wijewardhana
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We investigate a model of dynamical electroweak symmetry breaking via a dual gravitational description. The gravity dual is obtained by embedding a D7  antiD7 pair of branes into a type IIB background that is dual to a walking gauge theory. We develop further a previous study of this model. In particular, we show that there is a nontrivial relation that needs to be satisfied in order for axialvector modes to exist. Furthermore, we compute explicitly the electroweak S parameter. The result is...
Source: http://arxiv.org/abs/1105.4185v1
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JieSheng Yu; ZhiFeng Sun; Xiang Liu; Qiang Zhao
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Inspired by the newly observed three resonances X(1835), X(2120) and X(2370), in this work we systematically study the twobody strong decays and double pion decays of $\eta(1295)/\eta(1475)$, $\eta(1760)/X(1835)$ and $X(2120)/X(2370)$ by categorizing $\eta(1295)/\eta(1475)$, $\eta(1760)/X(1835)$, X(2120) and X(2370) as the radial excitations of $\eta(548)/\eta^\prime(958)$. Our numerical results indicate the followings: (1) The obtained theoretical strong decay widths of three pseudoscalar...
Source: http://arxiv.org/abs/1104.3064v3
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Unver Ciftci; Holger Waalkens
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Recently the phase space structures governing reaction dynamics in Hamiltonian systems have been identified and algorithms for their explicit construction have been developed. These phase space structures are induced by saddle type equilibrium points which are characteristic for reaction type dynamics. Their construction is based on a Poincar{\'e}Birkhoff normal form. Using tools from the geometric theory of Hamiltonian systems and their reduction we show in this paper how the construction of...
Source: http://arxiv.org/abs/1105.4180v1
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Klaus Halterman; Oriol T. Valls; Mohammad Alidoust
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We study proximity effects in clean nanoscale superconductornormal metalsuperconductor (S$\mid$N$\mid$S) graphene heterostructures using a selfconsistent numerical solution to the continuum Dirac Bogoliubovde Gennes (DBdG) equations. We obtain results for the pair amplitude and the local density of states (DOS), as a function of doping and of the geometrical parameters determining the width of the structures. The superconducting correlations are found to penetrate the normal graphene layers...
Source: http://arxiv.org/abs/1105.4140v1
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Azam Hokmabadi; Behrooz Mashayekhy; Fahimeh Mohammadzadeh
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This article is devoted to present an explicit formula for the $c$th nilpotent multiplier of nilpotent products of some cyclic groups $G={\bf {Z}}\stackrel{n_1}{*}{\bf {Z}}\stackrel{n_2}{*}...\stackrel{n_{t1}}{*}{\bf {Z}}\stackrel{n_{t}}{*} {\bf {Z}}_{m_{t+1}}\stackrel{n_{t+1}}{*}{\bf {Z}}_{m_{t+2}}\stackrel{n_{t+2}}{*}...\stackrel{n_{k}}{*}{\bf{Z}}_{m_{k+1}}$, where $m_{i+1}  m_i$ for all $t+1 \leq i \leq k$ and $c \geq n_1\geq n_2\geq ...\geq n_t\geq ...\geq n_{k}$ such that $...
Source: http://arxiv.org/abs/1105.4012v1
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LHC Higgs Cross Section Working Group; S. Dittmaier; C. Mariotti; G. Passarino; R. Tanaka; J. Baglio; P. Bolzoni; R. Boughezal; O. Brein; C. CollinsTooth; S. Dawson; S. Dean; A. Denner; S. Farrington; M. Felcini; M. Flechl; D. de Florian; S. Forte; M. Grazzini; C. Hackstein; T. Hahn; R. Harlander; T. Hartonen; S. Heinemeyer; J. Huston; A. Kalinowski; M. KrÃ¤mer; F. Krauss; J. S. Lee; S. Lehti; F. Maltoni; K. Mazumdar; S. O. Moch; A. MÃ¼ck; M. MÃ¼hlleitner; P. Nason; C. Neu; C. Oleari; J. Olsen; S. Palmer; F. Petriello; G. Piacquadio; A. Pilaftsis; C. T. Potter; I. Puljak; J. Qian; D. Rebuzzi; L. Reina; H. Rzehak; M. Schumacher; P. Slavich; M. Spira; F. StÃ¶ckli; R. S. Thorne; M. Vazquez Acosta; T. Vickey; A. Vicini; D. Wackeroth; M. Warsinsky; M. Weber; G. Weiglein; C. Weydert; J. Yu; M. Zaro; T. Zirke
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This Report summarizes the results of the first 10 months' activities of the LHC Higgs Cross Sections Working Group. The main goal of the working group was to present the statusofart on Higgs Physics at the LHC integrating all new results that have appeared in the last few years. The Report is more than a mere collection of the proceedings of the general meetings. The subgroups have been working in different directions. An attempt has been made to present the first Report from these subgroups...
Source: http://arxiv.org/abs/1101.0593v3
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Maxime Bois; Eric Emsellem; Frederic Bournaud; Katherine Alatalo; Leo Blitz; Martin Bureau; Michele Cappellari; Roger L. Davies; Timothy A. Davis; P. T. de Zeeuw; PierreAlain Duc; Sadegh Khochfar; Davor Krajnovic; Harald Kuntschner; PierreYves Lablanche; Richard M. McDermid; Raffaella Morganti; Thorsten Naab; Tom Oosterloo; Marc Sarzi; Nicholas Scott; Paolo Serra; AnneMarie Weijmans; Lisa M. Young
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We study the formation of earlytype galaxies through mergers with a sample of 70 highresolution (softening length < 60 pc and 12*10^6 particles) numerical simulations of binary mergers of disc galaxies and 16 simulations of ETG remergers. These simulations, designed to accompany observations and models conducted within the Atlas3D project, encompass various mass ratios (from 1:1 to 6:1), initial conditions and orbital parameters. The progenitor disc galaxies are spirallike with bulge to...
Source: http://arxiv.org/abs/1105.4076v1
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Andrea Meucci; J. A. Caballero; C. Giusti; J. M. Udias
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The analysis of the recent experimental data on chargedcurrent neutrinonucleus scattering cross sections measured at MiniBooNE requires fully relativistic theoretical descriptions also accounting for the role of final state interactions. In this work we evaluate inclusive quasielastic differential neutrino cross sections within the framework of the relativistic impulse approximation. Results based on the relativistic mean field potential are compared with the ones corresponding to the...
Source: http://arxiv.org/abs/1103.0636v2
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V. Blanco; J. C. Rosales
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We present a procedure to enumerate the whole set of numerical semigroups with a given Frobenius number F, S(F). The methodology is based on the construction of a partition of S(F) by a congruence relation. We identify exactly one irreducible and one homogeneous numerical semigroup at each class in the relation, and from those two elements we reconstruct the whole class. An alternative more efficient method is proposed based on the use of the Kunzcoordinates vectors of the elements in S(F).
Source: http://arxiv.org/abs/1105.4600v1
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AiWu Zhang; BoXiang Yu; YuGuang Xie; HongBang Liu; ZhengHua An; ZhiGang Wang; Xiao Cai; XiLei Sun; Feng Shi; Jian Fang; Zhen Xue; QiWen Lu; LiJun Sun; YongShuai Ge; YingBiao Liu; Tao Hu; Li Zhou; JunGuang Lu
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The gas gain and energy resolution of single and double THGEM detectors (5{\times}5cm2 effective area) with minirims (rim is less than 10{\mu}m) were studied. The maximum gain can reach 5{\times}103 and 2{\times}105 for single and double THGEM respectively, while the energy resolution of 5.9 keV Xray varied from 18% to 28% for both single and double THGEM detectors of different hole sizes and thicknesses.All the experiments were investigated in mixture of noble gases(argon,neon) and small...
Source: http://arxiv.org/abs/1105.1757v2
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Amit Einav; Michael Loss
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The sharp trace inequality of Jose Escobar is extended to traces for the fractional Laplacian on R^n and a complete characterization of cases of equality is discussed. The proof proceeds via Fourier transform and uses Lieb's sharp form of the HardyLittlewoodSobolev inequality.
Source: http://arxiv.org/abs/1105.4079v1
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Huan Dong; T. T. S. Kuo; J. W. Holt
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Shellmodel calculations for several mass 1619 nuclei are performed using the N$^3$LO twonucleon potential $V_{2N}$ with and without the addition of an inmedium threenucleon potential $V_{3N}^{med}$, which is a densitydependent effective twonucleon potential recently derived from the leadingorder chiral threenucleon force $V_{3N}$ by Holt, Kaiser, and Weise. We first calculate the $V_{lowk}$ lowmomentum interactions from $V_{2N}$ and $V_{3N}^{med}$. The shellmodel effective...
Source: http://arxiv.org/abs/1105.4169v1
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Ion Garate; M. Franz
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We present a theoretical study of interacting electronhole pairs located on a magnetized surface of a strong topological insulator (TI). The excitonic energy levels and the optical absorption on such surface display unique and potentially measurable features such as (i) an enhanced binding energy for excitons whose total angular momentum is aligned with the magnetic exchange field, (ii) a stark dependence of the optical absorption on the direction of the magnetic exchange field as well as on...
Source: http://arxiv.org/abs/1103.5059v2
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M. Magliocchetti; P. Santini; G. Rodighiero; A. Grazian; H. Aussel; B. Altieri; P. Andreani; S. Berta; J. Cepa; H. CastaÃ±eda; A. Cimatti; E. Daddi; D. Elbaz; R. Genzel; C. Gruppioni; D. Lutz; B. Magnelli; R. Maiolino; P. Popesso; A. Poglitsch; F. Pozzi; M. SanchezPortal; N. M. FÃ¶rster Schreiber; E. Sturm; L. Tacconi; I. Valtchanov
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ABRIDGEDThis paper presents the first direct estimate of the 3D clustering properties of farinfrared sources up to z~3. This has been possible thanks to the Pacs Evolutionary Probe (PEP) survey of the GOODS South field performed with the PACS instrument onboard the Herschel Satellite. An analysis of the twopoint correlation function over the whole redshift range spanned by the data reports for the correlation length, r_0~6.3 Mpc and r_0~6.7 Mpc, respectively at 100um and 160um, corresponding...
Source: http://arxiv.org/abs/1105.4093v1
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Miguel Couceiro; Michel Grabisch
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The symmetric maximum, denoted by v, is an extension of the usual max operation so that 0 is the neutral element, and x is the symmetric (or inverse) of x, i.e., x v(x)=0. However, such an extension does not preserve the associativity of max. This fact asks for systematic ways of parenthesing (or bracketing) terms of a sequence (with more than two arguments) when using such an extended maximum. We refer to such systematic (predefined) ways of parenthesing as computation rules. As it turns out...
Source: http://arxiv.org/abs/1105.4174v1
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YiFu Cai; James B. Dent; Damien A. Easson
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We propose a warm inflationary model in the context of relativistic Dbrane inflation in a warped throat, which has DiracBornInfeld (DBI) kinetic term and is coupled to radiation through a dissipation term. The perturbation freezes at the sound horizon and the power spectrum is determined by a combination of the dissipative parameter and the sound speed parameter. The thermal dissipation ameliorates the {\it eta} problem and softens theoretical constraints from the extradimensional volume...
Source: http://arxiv.org/abs/1011.4074v2
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A. L. Efros; Brian Skinner; B. I. Shklovskii
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The oneparticle density of states (1PDOS) in a system with localized electron states vanishes at the Fermi level due to the Coulomb interaction between electrons. Derivation of the Coulomb gap uses stability criteria of the ground state. The simplest criterion is based on the excitonic interaction of an electron and a hole and leads to a quadratic 1PDOS in the threedimensional (3D) case. In 3D, higher stability criteria, including two or more electrons, were predicted to exponentially...
Source: http://arxiv.org/abs/1105.1712v2
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Tim Johannsen; Dimitrios Psaltis
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According to the nohair theorem, astrophysical black holes are uniquely characterized by their masses and spins and are described by the Kerr metric. Several parametric deviations from the Kerr metric have been suggested to study observational signatures in both the electromagnetic and gravitationalwave spectra that differ from the expected Kerr signals. Due to the nohair theorem, however, such spacetimes cannot be regular everywhere outside the event horizons, if they are solutions to the...
Source: http://arxiv.org/abs/1105.3191v2
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Jacek Mulak; Maciej Mulak
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Any electron eigenstate \Psi>of the paramagnetic ion openshell is characterized by the three independent multipole asphericities A_{k}= for k=2,4 and 6 related to the second moments of the relevant crystalfield splittings by \sigma_{k}^{2}= ]A_{k}^{2}S_{k}^{2}, where S_{k}^{2}= ]\sum_{q}B_{kq}^{2}. The A_{k} can serve as a reliable measure of the state \Psi>capability for the splitting produced by the krank component of the crystalfield Hamiltonian and allow one to verify any...
Source: http://arxiv.org/abs/1105.4168v1
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Michael T. Goodrich; Michael Mitzenmacher; Olga Ohrimenko; Roberto Tamassia
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We study the problem of providing privacypreserving access to an outsourced honestbutcurious data repository for a group of trusted users. We show that such privacypreserving data access is possible using a combination of probabilistic encryption, which directly hides data values, and stateless oblivious RAM simulation, which hides the pattern of data accesses. We give simulations that have only an $O(\log n)$ amortized time overhead for simulating a RAM algorithm, $\cal A$, that has a...
Source: http://arxiv.org/abs/1105.4125v1
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The usual discussions about black hole dynamics involve analogies with laws of thermodynamics especially in connection with black hole entropy and the associated holographic principle. We explore complementary aspects involving hydrodynamics of the horizon geometry through the membrane paradigm. New conceptual connections complementing usual thermodynamic arguments suggest deep links between diverse topics like black hole decay, quantum circulation and viscosity. Intriguing connections between...
Source: http://arxiv.org/abs/1105.4019v1
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Hiroko Watanabe; Gregal Vissers; Reizaburo Kitai; Luc Rouppe van der Voort; Robert J. Rutten
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Highresolution imagingspectroscopy movies of solar active region NOAA 10998 obtained with the CRisp Imaging SpectroPolarimeter (CRISP) at the Swedish 1m Solar Telescope show very bright, rapidly flickering, flamelike features that appear intermittently in the wings of the Balmer Halpha line in a region with moat flows and likely some flux emergence. They show up at regular Halpha bluewing bright points that outline magnetic network, but flare upward with much larger brightness and...
Source: http://arxiv.org/abs/1105.4008v1
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Experimental data for hadron radial and elliptic flow are used to investigate their influence on the shape of the thermal photon spectrum at RHIC. Leaving alone the actual mechanism of photon production and its time evolution, we concentrate on the spectrum shape. Radial and longitudinal flow of the bulk can change significantly the observed photon energy spectrum via the Doppler Effect. Experimental thermal photon data are described by local frame temperature parameter which depends on the...
Source: http://arxiv.org/abs/1105.4033v1
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Antonio J. Di Scala; Daniele Zuddas
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We show that any compact almostcomplex manifold of complex dimension m can be pseudoholomorphically embedded in R^(6m) equipped with a suitable almostcomplex structure.
Source: http://arxiv.org/abs/1005.4619v5
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Ryo Tamura; Naoki Kawashima
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Using a Monte Carlo method, we study the finitetemperature phase transition in the twodimensional classical Heisenberg model on a triangular lattice with or without easyplane anisotropy. The model takes account of competing interactions: a ferromagnetic nearestneighbor interaction $J_1$ and an antiferromagnetic third nearestneighbor interaction $J_3$. As a result, the ground state is a spiral spin configuration for $4 < J_1/J_3 < 0$. In this structure, global spin rotation cannot...
Source: http://arxiv.org/abs/1105.2452v2
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G. Coppola; M. Dall'Ora; V. Ripepi; M. Marconi; I. Musella; G. Bono; A. M. Piersimoni; P. B. Stetson; J. Storm
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We present new and accurate nearinfrared (NIR) J, Kband time series data for the Galactic globular cluster (GC) M5 = NGC5904. Data were collected with SOFI at the NTT (71 J + 120 K images) and with NICS at the TNG (25 J + 22 K images) and cover two orthogonal strips across the center of the cluster of \approx 5 \times 10 arcmin^{2} each. These data allowed us to derive accurate mean Kband magnitudes for 52 fundamental (RR_{ab}) and 24 first overtone (RR_{c}) RR Lyrae stars. Using this sample...
Source: http://arxiv.org/abs/1105.4031v1
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D. Lukman; N. S. Mankoc Borstnik; H. B. Nielsen
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One step towards realistic KaluzaKlein[like] theories and a loop hole through the Witten's "nogo theorem" is presented for cases which we call an effective two dimensionality cases: In $d=2$ the equations of motion following from the action with the linear curvature leave spin connections and zweibeins undetermined. We present the case of a spinor in $d=(1+5)$ compactified on a formally infinite disc with the zweibein which makes a disc curved on an almost $S^2$ and with the spin...
Source: http://arxiv.org/abs/1001.4679v5
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Steven R. Warren; Daniel R. Weisz; Evan D. Skillman; John M. Cannon; Julianne J. Dalcanton; Andrew E. Dolphin; Robert C. Kennicutt, Jr.; Barbel Koribalski; Juergen Ott; Adrienne M. Stilp; Schuyler D. Van Dyk; Fabian Walter; Andrew A. West
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The origin of kpcscale holes in the atomic hydrogen (H I) distributions of some nearby dwarf irregular galaxies presents an intriguing problem. Star formation histories (SFHs) derived from resolved stars give us the unique opportunity to study past star forming events that may have helped shape the currently visible H I distribution. Our sample of five nearby dwarf irregular galaxies spans over an order of magnitude in both total H I mass and absolute Bband magnitude and is at the low mass...
Source: http://arxiv.org/abs/1105.4117v1
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E. M. Kantor; M. E. Gusakov
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We study the effects of finite stellar temperatures on the oscillations of superfluid neutron stars. The importance of these effects is illustrated with a simple example of a radially pulsating general relativistic star. Two main effects are taken into account: (i) temperature dependence of the entrainment matrix and (ii) the variation of the size of superfluid region with temperature. Four models are considered, which include either one or both of these two effects. Pulsation spectra are...
Source: http://arxiv.org/abs/1105.4040v1
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Richard C. Bradley
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In a paper that appeared in 2010, C. Tone proved a multivariate central limit theorem for some strictly stationary random fields of random vectors satisfying certain mixing conditions. The "normalization" of a given "partial sum" (or "block sum") involved matrix multiplication by a "standard 1/2 power" of its covariance matrix (a symmetric, positive definite matrix), and the limiting multivariate normal distribution had the identity matrix as its...
Source: http://arxiv.org/abs/1105.4132v1
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Jose MartinezBernal; Susan Morey; Rafael H. Villarreal
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Let G be a graph and let I be its edge ideal. Our main result shows that the sets of associated primes of the powers of I form an ascending chain. It is known that the sets of associated primes of I(i) and intcl(I(i)) stabilize for large i, where "intcl" denotes integral closure and I(i) denotes the ith power of I. We show that for edge ideals their corresponding stable sets are equal. To show our main result we use a classical result of Berge from matching theory and certain notions...
Source: http://arxiv.org/abs/1103.0992v3
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Taichi Kosugi; Takashi Miyake; Shoji Ishibashi
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We study the dependence of the spin splitting on the number $N$ of atomic layers, using firstprinciples calculation for Au(111) surface. When the slab of the atomic layers is sufficiently thick, the lower split state has a minimum away from $\bar{\Gamma}$, which is known as the Rashba effect. As the number of layers decreases, the minimum approaches $\bar{\Gamma}$, and it is located at $\bar{\Gamma}$ for $N \leq 14$. This crossover is analyzed in detail using two models: a tightbinding model...
Source: http://arxiv.org/abs/1105.4123v1
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Elena Beretta; Eric Bonnetier; Elisa Francini; And Anna L Mazzucato
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We derive asymptotic expansions for the displacement at the boundary of a smooth, elastic body in the presence of small inhomogeneities. Both the body and the inclusions are allowed to be anisotropic. This work extends prior work of CapdeBoscq and Vogelius ({\em Math. Modelling Num. Anal.} 37, 2003) for the conductivity case. In particular, we obtain an asymptotic expansion of the difference between the displacements at the boundary with and without inclusions, under Neumann boundary...
Source: http://arxiv.org/abs/1105.4111v1
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Sergey E. Koposov; G. Gilmore; M. G. Walker; V. Belokurov; N. Wyn Evans; M. Fellhauer; W. Gieren; D. Geisler; L. Monaco; J. E. Norris; S. Okamoto; J. Penarrubia; M. Wilkinson; R. F. G. Wyse; D. B. Zucker
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We develop, implement and characterise an enhanced data reduction approach which delivers precise, accurate, radial velocities from moderate resolution spectroscopy with the fibrefed VLT/FLAMES+GIRAFFE facility. This facility, with appropriate care, delivers radial velocities adequate to resolve the intrinsic velocity dispersions of the very faint dSph dwarf galaxies. Importantly, repeated measurements let us reliably calibrate our individual velocity errors ($0.2 \leq \delta_V\leq 5$ km...
Source: http://arxiv.org/abs/1105.4102v1
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Brice R. Mbombo; Vladimir G. Pestov
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According to Kat\vetov (1988), for every infinite cardinal $\mathfrak m$ satisfying ${\mathfrak m}^{\mathfrak n}\leq {\mathfrak m}$ for all ${\mathfrak n}
Source: http://arxiv.org/abs/1012.1056v6
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Alberto A. Condori
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Let $\Phi$ be a continuous $n\times n$ matrixvalued function on the unit circle $\T$ such that the $(k1)$th singular value of the Hankel operator with symbol $\Phi$ is greater than the $k$th singular value. In this case, it is wellknown that $\Phi$ has a unique superoptimal meromorphic approximant $Q$ in $H^{\infty}_{(k)}$; that is, $Q$ has at most $k$ poles in the unit disc $\mathbb{D}$ (i.e. the McMillan degree of $Q$ in $\mathbb{D}$ is at most $k$) and $Q$ minimizes the essential suprema...
Source: http://arxiv.org/abs/1103.3906v2
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Daniel Waltner; Jack Kuipers; Klaus Richter
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Transport properties of open chaotic ballistic systems and their statistics can be expressed in terms of the scattering matrix connecting incoming and outgoing wavefunctions. Here we calculate the dependence of correlation functions of arbitrarily many pairs of scattering matrices at different energies on the Ehrenfest time using trajectory based semiclassical methods. This enables us to verify the prediction from effective random matrix theory that one part of the correlation function obtains...
Source: http://arxiv.org/abs/1007.1595v2
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Victor Chua; Hong Yao; Gregory A. Fiete
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We study an exactly solvable quantum spin model of Kitaev type on the kagome lattice. We find a rich phase diagram which includes a topological (gapped) chiral spin liquid with gapless chiral edge states, and a gapless chiral spin liquid phase with a spin Fermi surface. The ground state of the current model contains an odd number of electrons per unit cell which qualitatively distinguishes it from previously studied exactly solvable models with a spin Fermi surface. Moreover, we show that the...
Source: http://arxiv.org/abs/1010.1035v2
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Peter Kuhn; Dirk Pauly
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We prove regularity results up to the boundary for time independent generalized Maxwell equations on Riemannian manifolds with boundary using the calculus of alternating differential forms. We discuss homogeneous and inhomogeneous boundary data and show 'polynomially weighted' regularity in exterior domains as well.
Source: http://arxiv.org/abs/1105.4091v1
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M. Anand; P. R. Kumar
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For every Gaussian network, there exists a corresponding deterministic network called the discrete superposition network. We show that this discrete superposition network provides a nearoptimal digital interface for operating a class consisting of many Gaussian networks in the sense that any code for the discrete superposition network can be naturally lifted to a corresponding code for the Gaussian network, while achieving a rate that is no more than a constant number of bits lesser than the...
Source: http://arxiv.org/abs/1005.0167v2