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Title: Approximation of continuous functions on Fr\'echet spacesCategory: math.FAAuthors: M. A. Mytrofanov, A. V. RavskyStudy Abstract: We consider approximations of a continuous function on a countable normed Fr\'{e}chet space by analytic and $*$-analytic. Also we found a <extra_id_0> of the existence of an extension of a continuous function from a dense subspace <extra_id_1> onto the space. Comments: 9 pages, in Ukrainian. English version is downloadable in the source file
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<extra_id_0> criterium <extra_id_1> of a topological space <extra_id_2>
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Title: Constants of Motion for Constrained Hamiltonian Systems: A Particle around a Charged Rotating Black HoleCategory: gr-qc hep-thAuthors: Takahisa Igata, Tatsuhiko Koike, Hideki IshiharaStudy Abstract: We discuss constants of motion of a particle under an external field in a curved spacetime, taking into account the Hamiltonian <extra_id_0> from reparametrization invariance <extra_id_1> particle orbit. As <extra_id_2> condition for the existence of a constant of <extra_id_3> obtain a set of equations with a hierarchical structure, which <extra_id_4> understood as a generalization of the Killing tensor equation. It <extra_id_5> generalization of the conventional argument in that it includes <extra_id_6> when the conservation condition holds only on the constraint surface in the phase space. <extra_id_7> it is shown that the constant of motion is associated with a <extra_id_8> We apply the <extra_id_9> constants of motion in the case <extra_id_10> charged particle in an electro-magnetic field in black hole spacetimes. We also demonstrate that gravitational and electro-magnetic fields exist <extra_id_11> particle has a constant of motion associated with <extra_id_12> tensor. Comments: <extra_id_13>
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<extra_id_0> constraint which arises <extra_id_1> of the <extra_id_2> the necessary and sufficient <extra_id_3> motion, we <extra_id_4> is <extra_id_5> is also a <extra_id_6> the case <extra_id_7> In that case, <extra_id_8> conformal Killing tensor. <extra_id_9> hierarchical equations and find <extra_id_10> of a <extra_id_11> in which a charged <extra_id_12> a conformal Killing <extra_id_13> 20 pages <extra_id_14>
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Title: Hybrid superconductor-semiconductor devices <extra_id_0> SiGe nanocrystals on siliconCategory: cond-mat.mes-hall cond-mat.supr-conAuthors: G. Katsaros, P. Spathis, M. Stoffel, F. Fournel, M. Mongillo, V. Bouchiat, F. Lefloch, A. Rastelli, O. G. Schmidt and S. De FranceschiStudy Abstract: The epitaxial growth of germanium on silicon leads <extra_id_1> the self-assembly of SiGe nanocrystals via a process that allows the size, composition and position of the nanocrystals to be controlled. This level of control, combined with an inherent compatibility with silicon technology, could prove useful in nanoelectronic applications. Here we report the confinement <extra_id_2> quantum-dot devices made by directly contacting individual SiGe nanocrystals with aluminium electrodes, and the production of hybrid superconductorsemiconductor devices, such as resonant supercurrent transistors, when the dot is strongly coupled to the electrodes. Charge transport measurements on weakly coupled quantum dots reveal <extra_id_3> energy spectra, with the confined hole states displaying anisotropic gyromagnetic factors and strong spin-orbit coupling strength with pronounced gate-voltage and magnetic-field dependence. Comments: 35 pages, 6 figures
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<extra_id_0> made from self-assembled <extra_id_1> to <extra_id_2> of holes in <extra_id_3> discrete <extra_id_4>
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<extra_id_0> New Spectrum for Nonlinear Operators in Banach SpacesCategory: math.SP math.FAAuthors: Alessandro Calamai, Massimo Furi, and Alfonso VignoliStudy Abstract: Given any continuous self-map f of a Banach space E over K (where K is R or <extra_id_1> given any point p of E, we define a subset <extra_id_2> called spectrum of f at p, which coincides with the usual spectrum sigma(f) of f in the linear <extra_id_3> generally, we show that sigma(f,p) is always closed and, when <extra_id_4> coincides with the spectrum sigma(f'(p)) of the Frechet derivative of f at p. Some applications to bifurcation theory are given and some peculiar examples <extra_id_5> are provided. Comments: 23 pages, 3 figures
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<extra_id_0> Title: A <extra_id_1> C) and <extra_id_2> sigma(f,p) of K, <extra_id_3> case. More <extra_id_4> f is C^1, <extra_id_5> of spectra <extra_id_6>
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Title: Powers of sets in free groupsCategory: math.GRAuthors: Stanislav SafinStudy Abstract: We prove that |A^n| > c_n |A|^{[\frac{n+1}{2}]} for any finite subset A of a free group if <extra_id_0> least two noncommuting elements, where c_n>0 are constants not depending on A. Simple examples show that the order of these estimates are the best possible for each n>0. Comments: 3 pages
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<extra_id_0> A contains at <extra_id_1>
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Title: U(1)-decoupling, KK and BCJ relations in $\mathcal{N}=4$ SYMCategory: hep-thAuthors: Yin Jia, Rijun Huang, Chang-Yong LiuStudy Abstract: We proved the color reflection relation, U(1)-decoupling, Kleiss-Kuijf and Bern-Carrasco-Johansson <extra_id_0> $\mathcal{N}=4$ Super Yang-Mills theory using $\mathcal{N}=4$ SYM version BCFW recursion relation, which depends only on the general properties of super-amplitudes. This verified the conjectured matter <extra_id_1> We also show that color reflection relation and U(1)-decoupling relation are special cases of KK relation, if we consider the KK relation as a general relation, <extra_id_2> <extra_id_3> two relations come out naturally as the special cases. Comments: 17 <extra_id_4>
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<extra_id_0> relation for color-ordered <extra_id_1> fields BCJ relation. <extra_id_2> then <extra_id_3> the former <extra_id_4> pages <extra_id_5>
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Title: Finite Temperature Schwinger ModelCategory: hep-th hep-latAuthors: Ivo Sachs and Andreas WipfStudy Abstract: The temperature dependence of the order parameter of the Schwinger model is calculated in <extra_id_0> functional integral <extra_id_1> that we solve the model on a finite torus and let the spatial extension tend to infinity at the end of the computations. The induced actions, <extra_id_2> zero-modes, <extra_id_3> Green functions and Wilson loop correlators on the torus are derived. We find the analytic form of the chiral condensate for any temperature and in <extra_id_4> it <extra_id_5> \< \bar\Psi\Psi \> \sim -2 <extra_id_6> large <extra_id_7> the induced photon mass. Comments: Pre-arXiv article from 1991, 22 pages
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<extra_id_0> the euclidean <extra_id_1> approach. For <extra_id_2> fermionic <extra_id_3> relevant <extra_id_4> particular show that <extra_id_5> behaves like <extra_id_6> T\exp(-\pi\sqrt{\pi}T/e) for temperatures <extra_id_7> compared to <extra_id_8>
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Title: Perturbation Theory Based on Darboux Transformation on One-Dimensional Dirac Equation in Quantum ComputationCategory: quant-phAuthors: Agung TrisetyarsoStudy Abstract: We present the recent works \cite{trisetyarso2011} on the application of Darboux transformation on one-dimensional Dirac equation related <extra_id_0> the field of Quantum <extra_id_1> The representation of physical system in one-dimensional equation and its transformation due to the Bagrov, Baldiotti, Gitman, and Shamshutdinova (BBGS)-Darboux transformation showing the possibility admitting the concept of relativity <extra_id_2> trade-off of concurrent condition of quantum and classical physics play into the area of QIC. The applications in cavity quantum electrodynamics <extra_id_3> proposal of quantum transistor are presented. Comments: 2 pages, 3 figures Information and Communication Technology (ICoICT), 2013
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<extra_id_0> to <extra_id_1> Information and Computation (QIC). <extra_id_2> and the <extra_id_3> and on the <extra_id_4>
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Title: Coulomb interaction and first order <extra_id_0> cond-mat.supr-conAuthors: S.V.Syzranov, I.L. Aleiner, B.L. Altshuler, K.B. EfetovStudy Abstract: The superconductor-insulator transition (SIT) in regular arrays of Josephson junctions is studied at low temperatures. Near the transition a Ginzburg-Landau type action containing the imaginary time is derived. The new feature of this action is that it contains a gauge field $\Phi $ describing the Coulomb interaction and changing the standard critical behavior. The solution of <extra_id_1> at zero temperature $T=0$ in the space <extra_id_2> the SIT is always of the first order. At finite temperatures, a tricritical point separates the lines of the first and second order phase transitions. The same conclusion holds for $d=2$ if the mutual capacitance is larger than the distance between <extra_id_3> pages, 1 figure
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<extra_id_0> superconductor-insulator transitionCategory: <extra_id_1> renormalization group (RG) equations derived <extra_id_2> dimensionality $d=3$ shows that <extra_id_3> junctions. Comments: 4.1 <extra_id_4>
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Title: The Accretion of Gas onto Galaxies as Traced by their SatellitesCategory: astro-ph.COAuthors: Guinevere Kauffmann, Cheng Li, Timothy M. HeckmanStudy Abstract: We have compiled a large sample of isolated central galaxies from the Sloan Digital Sky Survey, which do not have a neighbour of comparable brightness within a <extra_id_0> of 1 Mpc. We use the colours, luminosities and surface brightnesses of satellite galaxies in the vicinity of these objects to estimate their atomic gas <extra_id_1> to derive the average total mass of HI gas contained in satellites as a function of projected radius from the primary. Recent calibrations of merging timescales from <extra_id_2> are used to estimate the rate at which this gas <extra_id_3> onto the <extra_id_4> Our estimated accretion rates fall short of those needed to maintain the observed level of star <extra_id_5> these <extra_id_6> two orders of magnitude. <extra_id_7> strong correlations between the total mass of gas <extra_id_8> colours and specific star formation rates of central <extra_id_9> stellar <extra_id_10> <extra_id_11> <extra_id_12> if we consider the total stellar mass in the satellites, rather <extra_id_13> their total gas mass. We ask why star formation in the central galaxies should <extra_id_14> with gas contained in satellites at projected separations of a <extra_id_15> more, well outside the virial radius of the <extra_id_16> halos of these systems. We suggest that gas-rich satellites trace an underlying reservoir of ionized gas that is accreted continuously, and that provides the fuel for ongoing <extra_id_17> in the local Universe. Comments: 14 pages, 6 figures, submitted to MNRAS
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<extra_id_0> projected distance <extra_id_1> content and <extra_id_2> N-body simulations <extra_id_3> will accrete <extra_id_4> primaries. <extra_id_5> formation in <extra_id_6> systems by nearly <extra_id_7> Nevertheless, there are <extra_id_8> in satellites and the <extra_id_9> galaxies of all <extra_id_10> masses. The <extra_id_11> correlations are <extra_id_12> much weaker <extra_id_13> than <extra_id_14> be correlated <extra_id_15> Mpc or <extra_id_16> dark matter <extra_id_17> star formation in galaxies <extra_id_18>
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Title: Unravelling the role of the interface for spin injection into organic semiconductorsCategory: cond-mat.mtrl-sci cond-mat.mes-hallAuthors: Cl\'ement Barraud, Pierre Seneor, Richard Mattana, St\'ephane Fusil, Karim Bouzehouane, Cyrile Deranlot, Patrizio Graziosi, Luis Hueso, Ilaria Bergenti, Valentin Dediu, Fr\'ed\'eric Petroff, Albert FertStudy Abstract: Whereas spintronics brings <extra_id_0> spin degree of freedom to electronic devices, molecular/organic electronics adds the opportunity to play with the <extra_id_1> versatility. Here we show how, as a contender to commonly used inorganic materials, organic/molecular based spintronics devices can exhibit very large magnetoresistance and lead to tailored spin polarizations. We report on giant tunnel magnetoresistance of up to 300% in a (La,Sr)MnO3/Alq3/Co nanometer size magnetic <extra_id_2> Moreover, we propose a spin dependent transport model giving a new understanding of spin injection into organic materials/molecules. Our findings bring a new insight on how one could tune spin injection by molecular engineering and paves the way to chemical tailoring <extra_id_3> of spintronics devices. Comments: Original version. Revised version to appear <extra_id_4> <extra_id_5>
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<extra_id_0> the <extra_id_1> chemical <extra_id_2> tunnel junction. <extra_id_3> of the properties <extra_id_4> in Nature <extra_id_5> Physics. <extra_id_6>
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Title: Light hadron production in inclusive pp-scattering at LHCCategory: hep-ph <extra_id_0> A. V. Luchinsky, A. A. <extra_id_1> inclusive production of light mesons in pp-scattering is considered in the framework of reggeon phenomenology with supercritical Pomeron. Available low-energy data can be explained with three reggeon particles taken into account. With the obtained results rapidity and pseudorapidity distributions for light-meson production at LHC energies are <extra_id_2> figures, 1 table; minor changes: figures 2,3 changed, references <extra_id_3>
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<extra_id_0> hep-exAuthors: A. K. Likhoded, <extra_id_1> NovoselovStudy Abstract: The <extra_id_2> predicted. Comments: 6 pages, 3 <extra_id_3> updated <extra_id_4>
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Title: Zero-field <extra_id_0> of two-body Stoner particles with dipolar interactionCategory: cond-mat.mes-hall cond-mat.mtrl-sciAuthors: Z. Z. Sun, Alexander Lopez, John SchliemannStudy Abstract: Nanomagnetism has recently attracted explosive <extra_id_1> particular, because of the enormous potential applications in information industry, e.g. new harddisk technology, race-track memory[1], and logic devices[2]. Recent technological advances[3] allow for the fabrication of single-domain <extra_id_2> whose magnetization dynamics have been extensively studied, both experimentally and theoretically, involving magnetic fields[4-9] and/or by spin-polarized currents[10-20]. From an industrial point of view, important issues include lowering the critical switching field $H_c$, and achieving short reversal <extra_id_3> Here we predict a new technological perspective: $H_c$ can be dramatically lowered (including $H_c=0$) by appropriately engineering the dipole-dipole interaction (DDI) in a system of two <extra_id_4> particles. Here, in a modified Stoner-Wohlfarth (SW) limit, both of the above goals can be achieved. The experimental feasibility of realizing our proposal is illustrated on the <extra_id_5> nanoparticles. Comments: 5 pages, 4 figures
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<extra_id_0> magnetization reversal <extra_id_1> attention, in <extra_id_2> magnetic nanoparticles (Stoner particles), <extra_id_3> times. <extra_id_4> synchronized Stoner <extra_id_5> example of cobalt <extra_id_6>
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Title: <extra_id_0> fullerene and <extra_id_1> derivativesCategory: cond-mat.mes-hallAuthors: E.F.Sheka, B.S.Razbirin, E.A.Nikitina D.K.NelsonStudy Abstract: Conventionally, <extra_id_2> Ih symmetry of fullerene C60 is accepted which <extra_id_3> numerous calculations. However, this conclusion results from the consideration of the molecule electron system, of its odd <extra_id_4> a close-shell approximation without taking the <extra_id_5> Passing to the open-shell approximation has lead to both the energy and the symmetry lowering up to Ci. Seemingly contradicting to a high-symmetry pattern of experimental recording, particularly concerning the molecule electronic spectra, the finding is considered in the current paper from the continuous symmetry viewpoint. Exploiting both continuous symmetry measure and continuous symmetry content, was shown that formal Ci symmetry of the molecule is by 99.99% Ih. A similar continuous symmetry analysis of the fullerene <extra_id_6> explanation of a large variety of their optical spectra patterns within the framework of the same C1 formal symmetry <extra_id_7> strong stability of the C60 skeleton. Comments: 11 pages. 5 figures. <extra_id_8>
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<extra_id_0> Continuous symmetry of C60 <extra_id_1> its <extra_id_2> the <extra_id_3> is supported by <extra_id_4> electrons in particular, in <extra_id_5> electron spin into account. <extra_id_6> monoderivatives gives a reasonable <extra_id_7> exhibiting a <extra_id_8> 6 tables <extra_id_9>
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Title: Can Centre Surround Model Explain the Enhancement of Visual Perception through Stochastic Resonance?Category: physics.comp-ph q-bio.NCAuthors: Ajanta Kundu and Sandip SarkarStudy Abstract: We demonstrate <extra_id_0> centre surround model for simulating the enhancement of contrast sensitivity through <extra_id_1> observed in psychophysical experiments. We also show that this model could be used to simulate the contrast sensitivity function through <extra_id_2> The quality of the fit of <extra_id_3> <extra_id_4> simulated data is <extra_id_5> 4 pages,5 figures
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<extra_id_0> the ability of <extra_id_1> stochastic resonance <extra_id_2> stochastic resonance. <extra_id_3> measured contrast sensitivity <extra_id_4> function to the <extra_id_5> very good. Comments: <extra_id_6>
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Title: Modeling the spectral evolution <extra_id_0> PWNe <extra_id_1> N. Bucciantini (NORDITA, Albanova), J. Arons (U.C. Berkeley), E. Amato (INAF, Arcetri)Study <extra_id_2> new model for the spectral evolution of Pulsar Wind Nebulae inside Supernova Remnants. The model couples the long-term dynamics of these systems, as derived in the 1-D approximation, with a <extra_id_3> spectral evolution of the emitting plasma. Our goal is to provide a simplified theoretical description that can be used as a tool to put constraints on unknown properties <extra_id_4> a piece of work that is preliminary to any more accurate and sophisticated modeling. In the present paper we apply the newly developed <extra_id_5> to a few objects of different ages and luminosities. We find that an injection spectrum in the form of a broken-power law gives a satisfactory description of the emission for all the systems <extra_id_6> surprisingly, we also find that the intrinsic spectral break <extra_id_7> to be at a similar energy for all sources, in spite of the differences mentioned above. <extra_id_8> the implications of our findings on the workings of pulsar magnetospheres, pair multiplicity and on the particle acceleration mechanism(s) that might be at work at the pulsar wind termination shock. Comments: 20 Pages, 6 Figures, Submitted to MNRAS
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<extra_id_0> of <extra_id_1> inside SNRsCategory: astro-ph.HEAuthors: <extra_id_2> Abstract: We present a <extra_id_3> 1-zone description of the <extra_id_4> of PWN-SNR systems: <extra_id_5> model <extra_id_6> we consider. More <extra_id_7> turns out <extra_id_8> We discuss <extra_id_9>
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Title: Excess AGN Activity in the z=2.30 Protocluster in HS 1700+64Category: astro-ph.CO astro-ph.GAAuthors: J. A. Digby-North (ICL), K. Nandra (ICL), E. S. Laird (ICL), C. C. Steidel (CalTech), A. <extra_id_0> M. Bogosavljevi\'c (CalTech), D. K. Erb (UCSB), A. <extra_id_1> N. A. <extra_id_2> <extra_id_3> present the results of spectroscopic, narrow-band and X-ray observations of a z=2.30 protocluster in the field of the QSO HS 1700+643. Using a sample of BX/MD galaxies, which are selected <extra_id_4> be at z~2.2-2.7 by their rest-frame ultraviolet colours, we find that there are 5 protocluster AGN which have been identified by characteristic emission-lines in their optical/near-IR spectra; this represents an enhancement over the field significant at ~98.5 per cent confidence. Using a ~200 ks Chandra/ACIS-I observation of this field we <extra_id_5> total of 161 X-ray point sources to a Poissonian false-probability limit of 4x10^{-6} and identify 8 <extra_id_6> BX/MD galaxies. Two of these are spectroscopically confirmed protocluster members and are also classified as emission-line <extra_id_7> a similarly selected field sample the analysis indicates this is also evidence for an enhancement of X-ray selected BX/MD AGN over the field, significant at ~99 per cent confidence. Deep Lya narrow-band imaging reveals that a total of 4/123 Lya emitters (LAEs) are found to be associated with <extra_id_8> with two of these <extra_id_9> and one highly likely member. We do not find a <extra_id_10> activity in this <extra_id_11> over that of the field (result significant at only 87 per cent confidence). The X-ray emitting AGN fractions for the BX/MD and LAE samples are found to be 6.9_{-4.4}^{+9.2} <extra_id_12> respectively, for protocluster AGN with L_{2-10 keV}>4.6x10^{43} erg s^{-1} at z=2.30. These findings are similar to results from the z=3.09 protocluster in the SSA 22 field found by <extra_id_13> (2009), in that both suggest AGN activity is favoured in dense environments at z>2. Comments: 8 pages, 2 figures. Accepted <extra_id_14> MNRAS.
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<extra_id_0> Georgakakis (NOA), <extra_id_1> E. Shapley (UCLA), <extra_id_2> Reddy (NOAO) and J. Aird <extra_id_3> (UCSD)Study Abstract: We <extra_id_4> to <extra_id_5> detect a <extra_id_6> of these with <extra_id_7> AGN. When compared to <extra_id_8> X-ray sources, <extra_id_9> confirmed protocluster members <extra_id_10> significant enhancement of AGN <extra_id_11> LAE sample <extra_id_12> and 2.9_{-1.6}^{+2.9} per cent, <extra_id_13> Lehmer et al. <extra_id_14> for publication in <extra_id_15>
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<extra_id_0> measurements on a 94 GHz SIS mixerCategory: astro-ph.IM physics.app-ph physics.ins-detAuthors: L. Oberto, N. De Leo, M. Fretto, A. Tartari, L. Brunetti and V. LacquanitiStudy Abstract: In this paper we present the realization and a preliminary characterization of a SIS <extra_id_1> It has been developed for the MASTER experiment that consists in a three-band SIS receiver (94, 225 and 345 GHz) for astrophysical observations through the <extra_id_2> at high altitude <extra_id_3> measurements performed establish an upper limit to <extra_id_4> A comparison has been tried with the MASTER requirements and with state of the art results. A noise figure of 110 K has been obtained at 94 GHz, about 22 times the quantum <extra_id_5> accepted for publication <extra_id_6> Journal of Infrared <extra_id_7> Terahertz Waves, <extra_id_8> pages, 6 figures, 1 table
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<extra_id_0> Title: Realization and preliminary <extra_id_1> based receiver. <extra_id_2> atmospheric windows available <extra_id_3> dry sites. The <extra_id_4> the overall receiver noise temperature. <extra_id_5> limit. Comments: Version <extra_id_6> on <extra_id_7> Millimeter and <extra_id_8> 6 <extra_id_9>
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Title: Optimal branching asymmetry of hydrodynamic pulsatile treesCategory: cond-mat.stat-mech physics.bio-ph physics.med-phAuthors: <extra_id_0> Marcel FilocheStudy Abstract: Most of the studies on optimal transport are done <extra_id_1> regime conditions. <extra_id_2> examples in living systems where supply tree networks have to deliver products in a limited time due to the pulsatile character <extra_id_3> This is the case for mammals respiration for which air has to reach the <extra_id_4> before the start of expiration. We report here that introducing a systematic branching asymmetry allows to reduce the average delivery time of the products. It simultaneously increases its robustness against the unevitable variability of sizes related to morphogenesis. We then apply this approach to the human tracheobronchial tree. <extra_id_5> show that in this case all extremities are <extra_id_6> with fresh air, provided that the asymmetry is smaller than a critical threshold which happens to fit with the <extra_id_7> in the human lung. This could <extra_id_8> the structure is <extra_id_9> maximum <extra_id_10> that allows to feed <extra_id_11> with fresh air. Comments: 4 pages, 4 figures
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<extra_id_0> Magali Florens, Bernard Sapoval, <extra_id_1> for steady state <extra_id_2> Yet, there exists numerous <extra_id_3> of the flow. <extra_id_4> gas exchange units <extra_id_5> We <extra_id_6> supplied <extra_id_7> asymmetry measured <extra_id_8> indicate that <extra_id_9> adjusted at the <extra_id_10> asymmetry level <extra_id_11> all terminal units <extra_id_12>
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Title: Quantum Diffusion and Delocalization for Band Matrices with General DistributionCategory: math-ph math.MP math.PRAuthors: Laszlo <extra_id_0> Abstract: We consider Hermitian and symmetric random band matrices $H$ in $d \geq 1$ dimensions. The matrix <extra_id_1> by $x,y \in \Lambda \subset \Z^d$, are independent and their variances satisfy $\sigma_{xy}^2:=\E \abs{H_{xy}}^2 = W^{-d} f((x - y)/W)$ for some probability density $f$. We assume that the <extra_id_2> of each matrix element $H_{xy}$ is symmetric and exhibits subexponential decay. We prove that the time evolution of a quantum particle subject to the Hamiltonian $H$ is diffusive on time scales $t\ll W^{d/3}$. We also show <extra_id_3> length of the eigenvectors of $H$ is larger than a <extra_id_4> $W^{d/6}$ times the band width $W$. All results are uniform in the size $\abs{\Lambda}$ of the matrix. This extends our recent result \cite{erdosknowles} to general band matrices. As another consequence of our proof we <extra_id_5> a larger class of random matrices satisfying $\sum_x\sigma_{xy}^2=1$ for all $y$, the largest eigenvalue of $H$ is bounded with high probability by $2 + M^{-2/3 + \epsilon}$ for any $\epsilon > 0$, where $M \deq 1 / (\max_{x,y} \sigma_{xy}^2)$. Comments: Corrected typos and some inaccuracies in appendix C
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<extra_id_0> Erdos and Antti KnowlesStudy <extra_id_1> elements $H_{xy}$, indexed <extra_id_2> law <extra_id_3> that the localization <extra_id_4> factor <extra_id_5> show that, for <extra_id_6>
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Title: Some planar isospectral domainsCategory: math.DGAuthors: Peter Buser, John Conway, Peter Doyle, Klaus-Dieter SemmlerStudy Abstract: We give a number of examples of isospectral pairs of <extra_id_0> a particularly simple <extra_id_1> isospectrality. One of our examples is a pair of domains <extra_id_2> are <extra_id_3> isospectral but homophonic: Each <extra_id_4> distinguished point such that corresponding normalized <extra_id_5> equal values at the distinguished points. This shows that one really can't hear the shape of a drum. Comments: Version 1.0.1 dated 15 September 1994
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<extra_id_0> plane domains, and <extra_id_1> method of proving <extra_id_2> that <extra_id_3> not only <extra_id_4> domain has a <extra_id_5> Dirichlet eigenfunctions take <extra_id_6>
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Title: A new approach to reconstruction methods in $f(R)$ gravityCategory: gr-qc astro-ph.COAuthors: Sante Carloni, Rituparno Goswami and Peter K. S. DunsbyStudy Abstract: We present a <extra_id_0> approach <extra_id_1> method based on the use of the <extra_id_2> instead of a time <extra_id_3> scale factor. This allows the derivation and analysis of a set of new non-trivial cosmological solutions for $f(R)$-gravity. A number of simple examples are given. Comments: 5 pages, Revtex4
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<extra_id_0> new <extra_id_1> of the reconstruction <extra_id_2> cosmic parameters <extra_id_3> law for the <extra_id_4>
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Title: Triggered star formation and Young <extra_id_0> Population in Bright-Rimmed Cloud SFO 38Category: <extra_id_1> Rumpa Choudhury, Bhaswati Mookerjea, H. C. <extra_id_2> have investigated the young stellar population in and around SFO 38, one of the massive globules located in the northern part of the Galactic HII region IC 1396, using the Spitzer IRAC and MIPS observations (3.6 <extra_id_3> and followed up with ground based optical photometric <extra_id_4> observations. Based on the IRAC and MIPS colors and H-alpha emission we identify ~45 Young Stellar Objects (Classes 0/I/II) and 13 probable <extra_id_5> We derive the spectral <extra_id_6> K- and M-type stars), effective temperatures <extra_id_7> of the relatively bright and optically visible <extra_id_8> Based on optical photometry and theoretical isochrones, we estimate the spread in stellar ages to be between <extra_id_9> with a median age of 3 Myr and a mass distribution of 0.3--2.2 <extra_id_10> <extra_id_11> 0.5 Msun. Using the width of the H-alpha emission line measured at 10% peak intensity, we derive the mass accretion rates of individual objects to be between 10^{-10} to 10^{-8} Msun/yr. From the continuum-subtracted H-alpha line image, we find that the H-alpha emission of the globule is not spatially symmetric with respect to the O type ionizing star HD <extra_id_12> We clearly <extra_id_13> enhanced concentration of YSOs closer to the southern rim of SFO~38 and identify <extra_id_14> YSOs from the rim to the dense core of the cloud, <extra_id_15> of the Class II objects located at the bright rim. The YSOs appear to be aligned along two different directions towards the <extra_id_16> HD 206267 and the B0V type star HD 206773. This is consistent with the Radiation Driven Implosion (RDI) model for triggered star formation. (Abridged) Comments: Accepted for publication in ApJ
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<extra_id_0> Stellar <extra_id_1> astro-ph.GA astro-ph.SRAuthors: <extra_id_2> BhattStudy Abstract: We <extra_id_3> to 24 micron) <extra_id_4> and spectroscopic <extra_id_5> Pre Main Sequence candidates. <extra_id_6> types (mostly <extra_id_7> and individual extinction <extra_id_8> Class II objects. <extra_id_9> 1--8 Myr <extra_id_10> Msun with a <extra_id_11> median value around <extra_id_12> 206267. <extra_id_13> detect an <extra_id_14> an evolutionary sequence of <extra_id_15> with most <extra_id_16> O6.5V type star <extra_id_17>
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Title: Tol 2240-384 - a new low-metallicity AGN candidateCategory: astro-ph.COAuthors: Y. I. Izotov, N. G. Guseva, K. <extra_id_0> Stasinska, C. Henkel, P. PapaderosStudy Abstract: Active galactic <extra_id_1> typically been discovered in massive galaxies of high metallicity. We attempt to increase the number of AGN candidates <extra_id_2> galaxies. We present VLT/UVES <extra_id_3> VLT/FORS1 spectroscopic and NTT/SUSI2 photometric observations of <extra_id_4> galaxy Tol 2240-384 and perform a detailed study of its <extra_id_5> emission-line profiles. We determine abundances of nitrogen, <extra_id_6> S, Cl, Ar, and Fe by analyzing the fluxes of narrow components of <extra_id_7> empirical methods. We verify with a photoionisation model that the physics of the narrow-line component gas is similar to that in common metal-poor galaxies. Image deconvolution <extra_id_8> brightness regions in Tol 2240-384 separated by 2.4 kpc.The brightest southwestern region is surrounded by intense ionised gas emission <extra_id_9> scale of ~5 kpc. The profiles of the strong emission lines in the UVES spectrum are asymmetric and all these lines apart from Halpha and Hbeta can be fitted by two Gaussians of FWHM ~75-92 km/s separated by ~80 km/s implying that there are two regions of ionised gas emitting <extra_id_10> shapes of the Halpha and Hbeta lines are more complex. In <extra_id_11> line consists of two broad components of FWHM ~700 km/s and <extra_id_12> in addition to narrow components of two regions revealed from profiles of other lines. The extraordinarily high luminosity of the broad Halpha line of <extra_id_13> be accounted for by massive stars at different stages of their evolution. The broad Halpha emission persists over a period of 7 years, which excludes supernovae as a powering mechanism of this emission. <extra_id_14> likely arises from an accretion disc <extra_id_15> <extra_id_16> of mass ~10e7 Msun. Comments: <extra_id_17> figures, accepted for publication in Astronomy and Astrophysics
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<extra_id_0> J. Fricke, G. <extra_id_1> nuclei (AGNs) have <extra_id_2> in low metallicity <extra_id_3> and archival <extra_id_4> the low-metallicity emission-line <extra_id_5> morphology, chemical composition, and <extra_id_6> O, Ne, <extra_id_7> the emission lines using <extra_id_8> reveals two high-surface <extra_id_9> on a spatial <extra_id_10> narrow lines. The <extra_id_11> particular, the Halpha emission <extra_id_12> 2300 km/s, <extra_id_13> 3x10e41 erg/s cannot <extra_id_14> This emission most <extra_id_15> around a <extra_id_16> black hole <extra_id_17> 15 pages, 8 <extra_id_18>
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Title: Implication of the Steady State Equilibrium Condition for Electron-Positron Gas in the Neutrino-driven Wind from Proto-Neutron StarCategory: astro-ph.HE astro-ph.SRAuthors: Men-Quan Liu, Ye-Fei YuanStudy Abstract: Based <extra_id_0> the steady state equilibrium condition for neutron-proton-electron-positron gas in the neutrino-driven wind from protoneutron star, we estimate the initial electron fraction in the wind in a simple and <extra_id_1> We find that <extra_id_2> condition in the wind might be <extra_id_3> r-process nucleosynthesis. Comments: 5pages, 1 table. To appear in Proceedings for "Compact stars in the QCD phase diagram II (CSQCD II), May 20-24, 2009, KIAA at Peking University, Beijing - P. R. China [http://vega.bac.pku.edu.cn/rxxu/csqcd.htm]
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<extra_id_0> on <extra_id_1> effective way. <extra_id_2> the <extra_id_3> propriate for the <extra_id_4>
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Title: <extra_id_0> of G29.96-0.02: fitting the full SEDCategory: astro-ph.GAAuthors: J.M. Kirk, E. Polehampton, L. D. Anderson, J.-P. Baluteau, S. Bontemps, C. Joblin, S. C. Jones, D.A. Naylor, D. Ward-Thompson, G. J. White, A. Abergel, P. Ade, P. Andre, H. Arab, J.-P. Bernard, K. Blagrave, F. Boulanger, <extra_id_1> M. Compiegne, P. Cox, E. Dartois, G. Davis, R. <extra_id_2> T. Fulton, C. Gry, E. Habart, M. Huang, G. Lagache, T. Lim, S. <extra_id_3> P. Martin, M.-A. Miville-Deschenes, S. Molinari, H. Moseley, F. Motte, <extra_id_4> D. Pinheiro Gocalvez, J. A. Rodon, D. Russeil, P. Saraceno, S. Sidher, L. Spencer, B. Swinyard, <extra_id_5> Abstract: We use the SPIRE Fourier-Transform Spectrometer (FTS) on-board the ESA Herschel Space Telescope to analyse <extra_id_6> submillimetre spectrum of the Ultra-compact HII region G29.96-0.02. Spectral lines <extra_id_7> species including 13CO, CO, [CI], and [NII] are detected. A sparse map of the [NII] <extra_id_8> least one <extra_id_9> region neighbouring the clump containing the UCHII. The FTS spectra are combined with ISO SWS and LWS spectra and fluxes from the literature to present a <extra_id_10> of the <extra_id_11> orders of magnitude in wavelength. The quality of the spectrum longwards of 100 {\mu}m allows us to fit a single temperature greybody with temperature 80.3\pm0.6K and dust emissivity <extra_id_12> an <extra_id_13> with previous instruments. We estimate a mass <extra_id_14> the clump containing the HII region. The clump's bolometeric luminosity of 4 x 10^6 Lsol is comparable to, or slightly greater than, the known O-star powering <extra_id_15> region. Comments: 5 pages including affiliations, 4 <extra_id_16> by A&A
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<extra_id_0> Herschel-SPIRE spectroscopy <extra_id_1> M. Cohen, <extra_id_2> Emery, <extra_id_3> Madden, G. Makiwa, <extra_id_4> K. Okumura, <extra_id_5> and A. ZavagnoStudy <extra_id_6> the <extra_id_7> from <extra_id_8> emission shows at <extra_id_9> other HII <extra_id_10> detailed spectrum <extra_id_11> source spanning three <extra_id_12> index 1.73\pm0.02, <extra_id_13> accuracy rarely obtained <extra_id_14> of 1500 Msol for <extra_id_15> the UCHII <extra_id_16> figures, accepted <extra_id_17>
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Title: H2 reformation in post-shock regionsCategory: <extra_id_0> L.E. Kristensen and E. GavardiStudy Abstract: H2 formation is an <extra_id_1> process in post-shock regions, since H2 is an active participant in the cooling and shielding of the environment. The <extra_id_2> formation therefore has a strong effect on the temperature and chemical evolution in the post shock regions. <extra_id_3> developed a model for H2 formation on a graphite surface in warm conditions. The graphite surface <extra_id_4> model system <extra_id_5> of polycyclic aromatic hydrocarbon structures. Here this model is used to obtain a new description of the H2 formation rate as a function of gas temperature that can be implemented in molecular shock models. The H2 formation rate is substantially higher at high gas temperatures as compared to the original implementation of <extra_id_6> in shock models, because of the introduction of <extra_id_7> are chemically bonded to the grain (chemisorption). Since H2 plays such a key role in the cooling, the <extra_id_8> found to have a substantial effect on the predicted line <extra_id_9> of an important coolant in dissociative shocks <extra_id_10> I] at 63.2 and 145.5 micron. With the new <extra_id_11> agreement between model and observations is obtained. Since one of the goals of Herschel/PACS <extra_id_12> observe <extra_id_13> lines with higher spatial resolution and sensitivity than the former observations by ISO-LWS, this more <extra_id_14> is very timely to help with <extra_id_15> of <extra_id_16> 12 pages, 3 figures, 1 table, accepted in MNRAS Letters
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<extra_id_0> astro-ph.SRAuthors: H.M. Cuppen, <extra_id_1> important <extra_id_2> onset of H2 <extra_id_3> We recently <extra_id_4> acts as a <extra_id_5> for grains containing large areas <extra_id_6> this rate <extra_id_7> H atoms which <extra_id_8> increased rate is <extra_id_9> fluxes <extra_id_10> [O <extra_id_11> model a better <extra_id_12> will be to <extra_id_13> these <extra_id_14> accurate model <extra_id_15> the interpretation <extra_id_16> these future results. Comments: <extra_id_17>
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Title: The central region of spiral galaxies as seen by <extra_id_0> M81, M99 and M100Category: astro-ph.GA astro-ph.COAuthors: M. Sauvage, N. Sacchi, G. J. Bendo, A. Boselli, <extra_id_1> D. Wilson, R. Auld, M. Baes, M. J. Barlow, J. J. Bock, M. Bradford, V. Buat, <extra_id_2> P. Chanial, <extra_id_3> <extra_id_4> Clements, A. Cooray, D. Cormier, L. Cortese, J. I. Davies, E. Dwek, S. A. Eales, D. Elbaz, M. Galametz, F. Galliano, W. K. Gear, J. Glenn, H. L. Gomez, M. Griffin, S. Hony, K. G. Isaak, L. R. <extra_id_5> Lu, S. C. Madden, B. O'Halloran, K. Okumura, S. Oliver, M. J. Page, P. Panuzzo, A. <extra_id_6> J. Parkin, I. Perez-Fournon, N. <extra_id_7> E. Rigby, H. Roussel, A. Rykala, <extra_id_8> P. Schirm, M. W. L. Smith, L. Spinoglio, J. <extra_id_9> M. Symeonidis, M. Trichas, M. Vaccari, <extra_id_10> H. Wozniak, G. S. Wright, W. <extra_id_11> With appropriate spatial resolution, images of spiral galaxies in thermal infrared (~10 micron and beyond) often reveal a bright central component, distinct from the stellar bulge, superimposed on a disk with prominent spiral arms. ISO and Spitzer studies have shown that much of the scatter in the mid-infrared <extra_id_12> galaxies is related to changes in the relative importance of these two components, rather than to <extra_id_13> such <extra_id_14> morphological <extra_id_15> star formation rate, that <extra_id_16> properties of the galaxy as a whole. With the Herschel imaging capability from <extra_id_17> micron, we revisit this two-component approach at longer wavelengths, to see if <extra_id_18> working description of the brightness distribution of galaxies, and to determine its implications <extra_id_19> interpretation of global far-infrared properties of galaxies. Comments: 5 pages, <extra_id_20> figures, accepted for the A&A Herschel Special Issue
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<extra_id_0> Herschel. <extra_id_1> M. Pohlen, C. <extra_id_2> N. Castro-Rodriguez, <extra_id_3> S. Charlot, L. Ciesla, <extra_id_4> D. L. <extra_id_5> Levenson, N. <extra_id_6> Papageorgiou, T. <extra_id_7> Rangwala, E. <extra_id_8> B. Schulz, M. R. <extra_id_9> A. Stevens, S. Srinivasan, <extra_id_10> L. Vigroux, <extra_id_11> W. ZeilingerStudy Abstract: <extra_id_12> colors of spiral <extra_id_13> other modifications, <extra_id_14> as the <extra_id_15> type or <extra_id_16> affect the <extra_id_17> 70 to 500 <extra_id_18> it still provides a <extra_id_19> on the <extra_id_20> 2 <extra_id_21>
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Title: Constrained Quantum Systems as an Adiabatic ProblemCategory: quant-ph math-ph math.MPAuthors: Jakob Wachsmuth, Stefan TeufelStudy Abstract: We derive the effective Hamiltonian for a quantum system constrained to a submanifold (the constraint <extra_id_0> space (the ambient space) in the asymptotic <extra_id_1> the restoring forces tend <extra_id_2> contrast to earlier works we consider at the same time the effects of variations in the <extra_id_3> and the effects of interior and exterior geometry which appear at different energy scales and thus provide, for the first time, a complete picture ranging over all interesting energy scales. We show that the leading order contribution to the effective Hamiltonian is the adiabatic potential given by <extra_id_4> of the confining <extra_id_5> the context of adiabatic quantum wave guides. At next to <extra_id_6> we see effects from the variation <extra_id_7> the normal eigenfunctions in form of a Berry connection. We apply our results to quantum wave guides and provide an example for the occurrence of a topological phase due to the geometry of <extra_id_8> circuit, i.e. a closed quantum wave <extra_id_9> 4 figures
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<extra_id_0> manifold) of configuration <extra_id_1> limit where <extra_id_2> to infinity. In <extra_id_3> constraining potential <extra_id_4> an eigenvalue <extra_id_5> potential well-known in <extra_id_6> leading order <extra_id_7> of <extra_id_8> a quantum wave <extra_id_9> guide. Comments: 19 pages, <extra_id_10>
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Title: <extra_id_0> of double heavy <extra_id_1> in a relativistic constituent three-quark model <extra_id_2> mixingCategory: hep-phAuthors: Tanja Branz, Amand Faessler, Thomas Gutsche, Mikhail <extra_id_3> Korner, Valery E. Lyubovitskij, Bettina OexlStudy Abstract: We study flavor-conserving radiative decays of double heavy baryons using <extra_id_4> Lorentz covariant constituent three-quark model. Decay rates are calculated and compared to each other in the full theory, keeping masses finite, and also in the heavy quark limit. <extra_id_5> in some detail hyperfine mixing effects. Comments: 23 pages, <extra_id_6>
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<extra_id_0> Radiative decays <extra_id_1> baryons <extra_id_2> including hyperfine <extra_id_3> A. Ivanov, Jurgen G. <extra_id_4> a manifestly <extra_id_5> We discuss <extra_id_6> 2 figures <extra_id_7>
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Title: Lattice model refinement of protein structuresCategory: cs.CE physics.comp-ph q-bio.QMAuthors: Martin Mann (1) and Alessandro Dal Pal\`u (2) ((1) Bioinformatics, <extra_id_0> (2) Dip. di Matematica, Universit\`a di Parma, Italy)Study Abstract: To find the best lattice model representation of a given full atom protein <extra_id_1> a hard computational problem. Several greedy methods have been <extra_id_2> usually biased and leave room for <extra_id_3> In this paper we formulate and implement a Constraint Programming method to refine such lattice structure models. We show that the approach is able to provide better quality solutions. The prototype is implemented in COLA and is based on limited discrepancy search. Finally, some promising extensions based on local search are discussed. Comments: In Proceedings of Workshop on Constraint Based Methods for Bioinformatics (WCB 2010); Jul 21, 2010; Edinburgh, UK (co-located with ICLP 2010); 7 <extra_id_4>
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<extra_id_0> University Freiburg, Germany, <extra_id_1> structure is <extra_id_2> suggested where results are <extra_id_3> improvement. <extra_id_4> pages <extra_id_5>
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Title: Detection of a magnetic field on HD108: clues to extreme magnetic braking and the Of?p phenomenonCategory: astro-ph.SRAuthors: F. Martins (1), <extra_id_0> (2), W.L.F. Marcolino (3,4), J.-C. Bouret (3,5), G.A. Wade (6), C. Escolano (3), I.D. Howarth (7) (1- GRAAL Montpellier, 2- LATT Toulouse, 3- LAM Marseille, 4- Observatorio Nacional, Rio de Janeiro, 5- NASA/GSFC, Greenbelt, 6- RMC, Kingston, 7- UCL London)Study Abstract: We report <extra_id_1> of a <extra_id_2> the Of?p star HD108. Spectropolarimetric observations conducted in 2007, 2008 and 2009 respectively with NARVAL@TBL and ESPaDOnS@CFHT reveal a clear Zeeman signature in the average Stokes V profile, <extra_id_3> on timescales of days to months and slowly increasing in amplitude <extra_id_4> of years. We speculate that this timescale is the same as that on which Ha emission is varying and is equal to the rotation period of the star. The corresponding longitudinal magnetic field, measured during each of the <extra_id_5> slowly from 100 to 150G, implying that <extra_id_6> of the putatively-dipolar large-scale magnetic field of HD108 is at least 0.5kG and most likely of the order of 1-2 kG. The stellar and wind properties are derived through a quantitative spectroscopic analysis with the code CMFGEN. The effective <extra_id_7> difficult to constrain because of the unusually strong HeI4471 and HeI5876 lines. Values in the range 33000-37000 K are preferred. A mass loss rate of about 1e-7 Msun/yr (with a clumping factor f=0.01) and a wind terminal velocity of 2000 km/s <extra_id_8> wind <extra_id_9> parameter eta_star is larger than 100, <extra_id_10> wind of HD108 is magnetically confined. Stochastic short-term variability is observed in the wind-sensitive lines but not in the photospheric <extra_id_11> the presence of pulsations. Material infall <extra_id_12> the confined wind is the most likely origin for lines formed in the inner wind. Wind-clumping also probably causes part of the Ha variability. The projected rotational velocity of HD108 is lower than 50 km/s, consistent with the spectroscopic and <extra_id_13> of a few decades. Overall, HD108 is very similar to the magnetic O star HD191612 <extra_id_14> an even slower rotation. Comments: 10 <extra_id_15> figures; MNRAS accepted
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<extra_id_0> J.-F. Donati <extra_id_1> the detection <extra_id_2> magnetic field on <extra_id_3> stable <extra_id_4> on timescales <extra_id_5> three seasons, increases <extra_id_6> the polar strength <extra_id_7> temperature is <extra_id_8> are derived. The <extra_id_9> confinement <extra_id_10> implying that the <extra_id_11> lines, excluding <extra_id_12> in <extra_id_13> photometric variation timescales <extra_id_14> except for <extra_id_15> pages, 6 <extra_id_16>
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Title: Introduction to Feynman IntegralsCategory: hep-phAuthors: Stefan WeinzierlStudy Abstract: In these lectures I will give an introduction to Feynman integrals. In the first part of the course I review the basics <extra_id_0> perturbative expansion in quantum field theories. In the second part of the course I will discuss more advanced topics: Mathematical aspects of <extra_id_1> integrals related to periods, shuffle algebras and multiple polylogarithms are <extra_id_2> well as practical algorithms for evaluating Feynman integrals. Comments: 43 pages, <extra_id_3> given at the summer school "Geometric and Topological Methods for Quantum Field Theory", July 2009, Villa <extra_id_4>
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<extra_id_0> of the <extra_id_1> loop <extra_id_2> covered as <extra_id_3> lectures <extra_id_4> de Leyva, Colombia <extra_id_5>
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Title: An Elliptic Curve-based Signcryption Scheme with Forward SecrecyCategory: cs.CRAuthors: M. Toorani, A. A. BeheshtiStudy <extra_id_0> curve-based <extra_id_1> introduced in this paper that effectively combines the functionalities of digital signature and encryption, and decreases the computational costs and communication overheads in comparison with the traditional signature-then-encryption schemes. It simultaneously provides the attributes of message confidentiality, authentication, integrity, unforgeability, non-repudiation, public verifiability, and forward secrecy of message confidentiality. Since it is <extra_id_2> curves and can use any fast and secure <extra_id_3> encrypting messages, it has great advantages to be used for security establishments in store-and-forward applications and when dealing with resource-constrained devices. Comments: 13 Pages, <extra_id_4> Figures, 2 Tables
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<extra_id_0> Abstract: An elliptic <extra_id_1> signcryption scheme is <extra_id_2> based on elliptic <extra_id_3> symmetric algorithm for <extra_id_4> 5 <extra_id_5>
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<extra_id_0> Paired states of interacting electrons in a <extra_id_1> latticeCategory: cond-mat.str-elAuthors: D.Souza and <extra_id_2> that two tight binding electrons that repel may <extra_id_3> bounded <extra_id_4> in two dimensions. The paired states form a band with energies that scale like the strength of the interaction potential. By applying an electric field we show that the dynamics of such states is that of a composite particle of charge 2e. <extra_id_5> still sustains Bloch-like states, so that if the two bands overlap single and paired states might <extra_id_6> for a bosonic fluid component that, if condensed, would decrease the resistance at low temperatures. The presence of two bands allows for new oscillations whose experimental detection would permit a direct measurement of the interaction potential strength. Comments: 7 pages, 3 figures
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<extra_id_0> Title: <extra_id_1> two dimensional <extra_id_2> F.ClaroStudy Abstract: We show <extra_id_3> form a <extra_id_4> pair <extra_id_5> The system <extra_id_6> coexist allowing <extra_id_7>
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Title: Growth in finite <extra_id_0> Lie type of bounded rankCategory: math.GRAuthors: L\'aszl\'o Pyber and Endre Szab\'oStudy Abstract: We prove that if L is a finite simple group of Lie type and A a symmetric set of generators <extra_id_1> <extra_id_2> <extra_id_3> |A|^{1+epsilon} where epsilon depends only on the Lie rank of L, or AAA=L. This implies that for a family of simple groups L of Lie type of bounded rank the diameter of any Cayley graph is polylogarithmic in |L|. We obtain a similar bound for the diameters of all Cayley graphs of perfect subgroups of GL(n,p) generated by their elements of order p. We also obtain some new families of expanders. We also prove the following partial extension. Let G be a subgroup of GL(n,p), p a prime, and S a symmetric set of generators of G satisfying |S^3|\le K|S| for some K. Then G has two normal subgroups H\ge P such that H/P is soluble, P is contained in S^6 <extra_id_4> <extra_id_5> by K^c cosets of H <extra_id_6> depends on n. We obtain results of similar flavour for sets generating infinite subgroups of GL(n,F), F an arbitrary field. Comments: 84 pages, various new results concerning non-growing <extra_id_7> were added
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<extra_id_0> simple groups of <extra_id_1> of L, <extra_id_2> then A grows <extra_id_3> i.e |AAA| > <extra_id_4> and S <extra_id_5> is covered <extra_id_6> where c <extra_id_7> subsets of linear groups <extra_id_8>
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Title: Evolving Neutron Star Low-Mass X-ray Binaries to Ulta-compact <extra_id_0> astro-ph.SRAuthors: Xiang-Dong LiStudy Abstract: The author presented <extra_id_1> results on <extra_id_2> evolution of NS <extra_id_3> the formation of UCXBs(Ma <extra_id_4> Li 2009 for details), and proposed a scenario for the formation of UCXBs from L/IMXBs with the aid of a CB disk in <extra_id_5> 7pages, 3figures. To appear in Proceedings for "Compact <extra_id_6> the QCD phase diagram II (CSQCD II), May 20-24, 2009, KIAA at <extra_id_7> Beijing - P. R. China [http://vega.bac.pku.edu.cn/rxxu/csqcd.htm]
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<extra_id_0> X-ray BinariesCategory: astro-ph.HE <extra_id_1> the <extra_id_2> the <extra_id_3> LMXBs and <extra_id_4> & <extra_id_5> this work. Comments: <extra_id_6> stars in <extra_id_7> Peking University, <extra_id_8>
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Title: Feature Selection Using Regularization in Approximate Linear Programs for Markov Decision ProcessesCategory: cs.AIAuthors: Marek Petrik, Gavin Taylor, <extra_id_0> <extra_id_1> Abstract: Approximate dynamic programming has been used successfully in a large variety of domains, but <extra_id_2> small set of provided approximation features to calculate solutions reliably. Large and rich sets of features can cause existing algorithms to overfit because of a limited number of samples. We address this shortcoming using $L_1$ regularization in approximate linear programming. Because the <extra_id_3> can automatically select the appropriate richness of features, its performance does not degrade with an increasing number of features. These results rely on new <extra_id_4> sampling bounds for regularized approximate linear programs. We also propose a computationally efficient homotopy method. The empirical evaluation of the approach shows that the proposed method performs <extra_id_5> simple MDPs and standard benchmark problems. Comments: Technical report corresponding to the ICML2010 submission of the same name
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<extra_id_0> Ron Parr, <extra_id_1> Shlomo ZilbersteinStudy <extra_id_2> it relies on a <extra_id_3> proposed method <extra_id_4> and stronger <extra_id_5> well on <extra_id_6>
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Title: <extra_id_0> criteria for the absence of arbitrage in <extra_id_1> modelsCategory: q-fin.GN math.PRAuthors: Aleksandar Mijatovi\'c and Mikhail UrusovStudy Abstract: We obtain a deterministic characterisation of <extra_id_2> lunch with vanishing risk}, the \emph{no generalised arbitrage} and the \emph{no relative <extra_id_3> in <extra_id_4> diffusion setting and examine <extra_id_5> of no-arbitrage relate to each other. Comments: 20 pages; most results in this paper were contained <extra_id_6> first version of submission 0905.3701; to appear in Finance & Stochastics
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<extra_id_0> Deterministic <extra_id_1> one-dimensional diffusion <extra_id_2> the \emph{no free <extra_id_3> arbitrage} conditions <extra_id_4> the one-dimensional <extra_id_5> how these notions <extra_id_6> in the <extra_id_7>
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Title: On the estimation of integrated covariance <extra_id_0> high dimensional diffusion processesCategory: stat.ME math.PR math.ST q-fin.ST stat.THAuthors: Xinghua Zheng, Yingying LiStudy Abstract: We consider the estimation of integrated covariance (ICV) matrices of high dimensional diffusion processes based on high frequency observations. We start by studying the most commonly used estimator, the realized covariance (RCV) matrix. We show that in the high dimensional case when the dimension $p$ and the observation frequency $n$ grow in the same rate, the limiting spectral distribution (LSD) of RCV depends on the covolatility process not only through the targeting ICV, but <extra_id_1> the <extra_id_2> varies in time. We establish a Mar\v{c}enko--Pastur type theorem for weighted sample covariance matrices, based on which we obtain <extra_id_3> for RCV for a class $\mathcal{C}$ of diffusion processes. The results explicitly demonstrate how the time variability of <extra_id_4> affects the <extra_id_5> We further propose an alternative estimator, the time-variation adjusted realized covariance (TVARCV) matrix. We show that for processes <extra_id_6> $\mathcal {C}$, the TVARCV possesses the desirable property that its LSD depends solely on that <extra_id_7> ICV through the Mar\v{c}enko--Pastur equation, and hence, in particular, the TVARCV can be <extra_id_8> empirical spectral distribution of the ICV by using existing algorithms. Comments: Published in at http://dx.doi.org/10.1214/11-AOS939 the <extra_id_9> (http://www.imstat.org/aos/) <extra_id_10> of Mathematical Statistics (http://www.imstat.org)
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<extra_id_0> matrices of <extra_id_1> also on how <extra_id_2> covolatility process <extra_id_3> a Mar\v{c}enko--Pastur type theorem <extra_id_4> the covolatility process <extra_id_5> LSD of RCV. <extra_id_6> in class <extra_id_7> of the targeting <extra_id_8> used to recover the <extra_id_9> Annals of Statistics <extra_id_10> by the Institute <extra_id_11>
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Title: Interior Matter Estimates of Rapidly Rotating Compact StarsCategory: astro-ph.HE astro-ph.SRAuthors: Na-na Pan, <extra_id_0> The authors try to probe the <extra_id_1> of rapidly rotating compact stars such <extra_id_2> millisecond pulsar SAX J1808.4-3658 <extra_id_3> sub-millisecond pulsar XTE J1739-285 in their <extra_id_4> comparing the genuine rotation frequencies under different theoretical <extra_id_5> data, which may exert more stringent constraint on <extra_id_6> of compact stars. According <extra_id_7> the SAX J1808.4-3658 is a star with <extra_id_8> and XTE J1739-285 a hybrid star. Comments: 4 pages, 2 figures. To appear in Proceedings for "Compact stars in the QCD phase diagram II (CSQCD II), May 20-24, 2009, KIAA at Peking University, Beijing - P. R. China <extra_id_9>
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<extra_id_0> Xiao-ping ZhengStudy Abstract: <extra_id_1> inner components <extra_id_2> as the <extra_id_3> and the possible <extra_id_4> own way by <extra_id_5> models with the observational <extra_id_6> matter composition <extra_id_7> to their treatment, <extra_id_8> exotic matter <extra_id_9> [http://vega.bac.pku.edu.cn/rxxu/csqcd.htm] <extra_id_10>
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Title: The Herschel revolution: unveiling the morphology of the high mass star formation sites N44 <extra_id_0> LMCCategory: astro-ph.COAuthors: S. Hony, <extra_id_1> Madden, P. Panuzzo, M. Meixner, <extra_id_2> Engelbracht, K. Misselt, M. Galametz, M. Sauvage, J. Roman-Duval, K. Gordon, B. Lawton, <extra_id_3> Bernard, A. Bolatto, K. Okumura, C.-H. R. Chen, R. Indebetouw, F. P. Israel, E. Kwon, A. Li, F. Kemper, M. S. Oey, M. RubioStudy Abstract: We study the structure of the <extra_id_4> of <extra_id_5> determine the interrelation between the HII regions and the environment from which they were formed. <extra_id_6> <extra_id_7> surroundings is key in determining how the radiation of the newly <extra_id_8> <extra_id_9> surrounds in a way <extra_id_10> <extra_id_11> used as a star formation tracer. We present new Herschel/SPIRE 250, 350 and 500 mum data of LHA 120-N44 <extra_id_12> LHA 120-N63 in the LMC. We construct average spectral energy distributions (SEDs) for annuli centered on the IR bright part of the star formation sites. The annuli cover ~10-~100 pc. We use a <extra_id_13> fit these SEDs to derive the dust column densities, characterise the incident radiation field and the abundance <extra_id_14> aromatic hydrocarbon molecules. We see a factor 5 <extra_id_15> in the radiation field energy density as a function <extra_id_16> radial distance around N63. N44 does not show a systematic trend. We construct a simple geometrical model to <extra_id_17> density <extra_id_18> the surroundings of these two regions. Herschel/SPIRE data have proven very efficient in deriving the dust mass distribution. We find that the radiation field <extra_id_19> sources behaves very differently. N63 is more or less spherically symmetric and the average radiation field drops with distance. N44 shows no systematic decrease of the radiation intensity which is <extra_id_20> to the <extra_id_21> the surrounding molecular <extra_id_22> and to the complex distribution of several star forming clusters in the region. Comments: Accepted for publication in A&A letters (Herschel special issue)
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<extra_id_0> and N63 in the <extra_id_1> F. Galliano, S. C. <extra_id_2> C. <extra_id_3> J.-P. <extra_id_4> medium surrounding sites <extra_id_5> high-mass star formation to <extra_id_6> The density <extra_id_7> distribution of the <extra_id_8> formed stars interacts <extra_id_9> with the <extra_id_10> that allows <extra_id_11> it to be <extra_id_12> and <extra_id_13> phenomenological dust model to <extra_id_14> of polycyclic <extra_id_15> decrease <extra_id_16> of <extra_id_17> derive the 3-D <extra_id_18> profile of <extra_id_19> in the two <extra_id_20> probably due <extra_id_21> inhomogeneity of <extra_id_22> material <extra_id_23>
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Title: Long-range spin-triplet proximity effect in Josephson junctions with multilayered ferromagnetsCategory: cond-mat.supr-conAuthors: Luka <extra_id_0> Zoran RadovicStudy Abstract: We study the proximity effect in SF'(AF)F'S and SF'(F)F'S planar junctions, where S is a <extra_id_1> superconductor, <extra_id_2> middle layers are clean or moderately diffusive ferromagnets. Middle layers consist of <extra_id_3> ferromagnets with antiparallel (AF) or <extra_id_4> that are not collinear with magnetizations in the neighboring F' layers. We use fully self-consistent <extra_id_5> the Eilenberger equations to <extra_id_6> <extra_id_7> amplitudes and the <extra_id_8> for arbitrary thickness of ferromagnetic layers and the angle between in-plane magnetisations. For moderate disorder in ferromagnets the triplet proximity effect is practically the same <extra_id_9> AF and F structures, like in the dirty limit. Triplet Josephson current is dominant for $d'\approx\hbar v_F/2h'$, <extra_id_10> is the F' layer thickness and $h'$ is the exchange energy. Our results are in a qualitative agreement with the recent experimental <extra_id_11> S. Khaire, M. A. Khasawneh, W. <extra_id_12> and N. <extra_id_13> Lett. \textbf{104}, 137002 (2010)]. Comments: 4 pages, 4 figures
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<extra_id_0> Trifunovic and <extra_id_1> clean conventional (s-wave) <extra_id_2> while F' and <extra_id_3> two equal <extra_id_4> parallel (F) magnetizations <extra_id_5> numerical solutions of <extra_id_6> calculate the superconducting <extra_id_7> pair <extra_id_8> Josephson current <extra_id_9> for <extra_id_10> where $d'$ <extra_id_11> observations [T. <extra_id_12> P. Pratt, <extra_id_13> O. Birge, Phys. Rev. <extra_id_14>
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<extra_id_0> evolution of protein-biofilms: Simulations and ExperimentsCategory: cond-mat.softAuthors: Y. Schmitt(1), H. H\"ahl(1), C. Gilow(1), H. Mantz(1) and K. Jacobs(1), O. Leidinger(2), M. Bellion(2) and L. Santen(2) ((1) Department of Experimental Physics, Saarland University, 66041 Saarbr\"ucken, Germany, (2) Department of Theoretical Physics, <extra_id_1> 66041 Saarbr\"ucken, Germany)Study Abstract: The control of biofilm formation is a challenging goal that has not been reached yet in many aspects. One is the role of van der <extra_id_2> another the importance of mutual interactions between the adsorbing and the adsorbed biomolecules ('critical <extra_id_3> combined exeperimental and theoretical approach is presented that fundamentally <extra_id_4> aspects. On <extra_id_5> lysozyme, {\alpha}-amylase and bovine serum albumin (BSA), the adsorption kinetics is studied. Composite substrates are used enabling a separation of the short- and the long-range forces. Though usually neglected, experimental evidence is given for the influence <extra_id_6> forces on the protein adsorption as revealed by <extra_id_7> <extra_id_8> three proteins were chosen for their different conformational stability in order to investigate the influence of conformational changes on the adsorption kinetics. Monte Carlo simulations are used to develop a model for these experimental results by assuming an internal degree of freedom to represent conformational changes. The simulations also provide data on the distribution of adsorption sites. By <extra_id_9> atomic force microscopy we can also test this distribution <extra_id_10> <extra_id_11> to e.g. investigate the <extra_id_12> adsorbed proteins. Comments: 13 pages, 10 figures; submitted
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<extra_id_0> Title: Structural <extra_id_1> Saarland University, <extra_id_2> Waals forces and <extra_id_3> crowding'). Here, a <extra_id_4> probes both <extra_id_5> three model proteins, <extra_id_6> of van der Waals <extra_id_7> in <extra_id_8> situ ellipsometry. The <extra_id_9> in situ <extra_id_10> experimentally which opens <extra_id_11> the possibility <extra_id_12> interactions between <extra_id_13>
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Title: <extra_id_0> <extra_id_1> Shape, Velocity Dispersion <extra_id_2> astro-ph.COAuthors: C. Ragone-Figueroa, M. Plionis, M. Merchan, S. Gottlober and G. YepesStudy Abstract: We use dark matter haloes identified in the MareNostrum Universe and galaxy groups identified in the Sloan Data Release 7 galaxy catalogue, to study the relation between <extra_id_3> halo dynamics, parametrizing out the mass of the systems. A strong shape-dynamics, independent of mass, correlation is present in the simulation data, <extra_id_4> to be due to different halo formation times. Early formation time haloes are, at the present epoch, more spherical and have higher velocity dispersions than late forming-time haloes. The halo shape-dynamics <extra_id_5> the projection in 2D (ie., among projected shape and 1-D velocity dispersion). A similar shape-dynamics correlation, independent of mass, is also found in the SDSS DR7 groups of galaxies and in order <extra_id_6> we have tested and used, as a proxy of the group <extra_id_7> a concentration parameter. We have found, as in the case of <extra_id_8> groups, corresponding to late formation times, have <extra_id_9> and higher elongations than groups with higher <extra_id_10> concentration, corresponding to early formation <extra_id_11> MNRAS in press (10 pages, 10 figures)
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<extra_id_0> The Relation <extra_id_1> Between Halo <extra_id_2> and Formation TimeCategory: <extra_id_3> halo shape and <extra_id_4> which we find it <extra_id_5> correlation, albeit weaker, survives <extra_id_6> to investigate its cause <extra_id_7> formation time, <extra_id_8> the simulated haloes, that less concentrated <extra_id_9> lower velocity dispersions <extra_id_10> values of <extra_id_11> times. Comments: <extra_id_12>
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Title: Subfield-Subcodes of Generalized Toric codesCategory: cs.IT math.ITAuthors: Fernando Hernando, Michael <extra_id_0> Popovici and Shraddha SrivastavaStudy Abstract: We study subfield-subcodes of <extra_id_1> codes over $\mathbb{F}_{p^s}$. These are the multidimensional analogues of BCH codes, which may be seen as subfield-subcodes <extra_id_2> We identify polynomial generators for subfield-subcodes of GT codes which allows us to determine the dimensions and obtain bounds for the minimum distance. We give several examples of binary and ternary subfield-subcodes of GT codes that are the best known codes of a given dimension and length. Comments: Submitted to 2010 IEEE International Symposium on Information Theory (ISIT 2010)
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<extra_id_0> E. O'Sullivan, Emanuel <extra_id_1> Generalized Toric (GT) <extra_id_2> of generalized Reed-Solomon codes. <extra_id_3>
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Title: Nonequilibrium dynamical mean-field calculations based on the non-crossing approximation <extra_id_0> its generalizationsCategory: cond-mat.str-elAuthors: Martin Eckstein and Philipp WernerStudy Abstract: We solve the impurity problem which arises within nonequilibrium dynamical mean-field theory for the Hubbard model by means of a self-consistent perturbation expansion around the atomic limit. While the lowest order, known as the non-crossing <extra_id_1> is reliable only when <extra_id_2> much larger than the bandwidth, low-order corrections to the NCA turn out to be sufficient to reproduce numerically exact Monte Carlo results in a <extra_id_3> range that covers the insulating phase and the metal-insulator crossover regime at not too low temperatures. As <extra_id_4> of the perturbative strong-coupling impurity solver we investigate the response of the double occupancy in the Mott insulating phase of the Hubbard model <extra_id_5> change of the interaction <extra_id_6> hopping, a technique which has been used as a probe of the Mott insulating state in ultracold fermionic gases. Comments: 14 pages, 9 figures
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<extra_id_0> and <extra_id_1> approximation (NCA), <extra_id_2> the interaction U is <extra_id_3> wide parameter <extra_id_4> an application <extra_id_5> to a dynamical <extra_id_6> or the <extra_id_7>
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Title: Resonance strengths in the 14N(p, \gamma)15O and 15N(p, \alpha \gamma)12C reactionsCategory: nucl-exAuthors: Michele Marta, Erik Trompler, Daniel Bemmerer, Roland Beyer, Carlo Broggini, Antonio Caciolli, Martin Erhard, Zsolt F\"ul\"op, Eckart Grosse, Gy\"orgy Gy\"urky, Roland Hannaske, Arnd R. Junghans, Roberto Menegazzo, Chithra Nair, Ronald Schwengner, Tam\'as Sz\"ucs, <extra_id_0> Vezz\'u, Andreas Wagner, Dmitry YakorevStudy Abstract: The 14N(p, \gamma)15O reaction is the <extra_id_1> reaction of the carbon-nitrogen-oxygen cycle of hydrogen burning in stars. As a consequence, it determines the rate of the cycle. The 15N(p, \alpha \gamma)12C reaction <extra_id_2> used <extra_id_3> for hydrogen depth profiling in materials. The 14N(p, \gamma)15O <extra_id_4> reactions have been studied simultaneously, using titanium nitride targets of natural isotopic composition and a proton beam. The strengths of the resonances at Ep = 1058 keV in 14N(p, \gamma)15O and at Ep = 897 and 430 keV in 15N(p, \alpha <extra_id_5> with improved precision, relative to the well-known resonance at Ep = 278 keV in 14N(p, \gamma)15O. The new recommended values <extra_id_6> 0.353$\pm$0.018, 362$\pm$20, and 21.9$\pm$1.0 eV for their respective strengths. In addition, the branching ratios for the <extra_id_7> the Ep = 1058 keV resonance in 14N(p, \gamma)15O have been redetermined. The data reported here should facilitate future studies of off-resonant capture in the 14N(p, \gamma)15O reaction that are needed for an improved R-matrix extrapolation of the cross section. In addition, the data on the 430 keV resonance in 15N(p, \alpha \gamma)12C may be useful for hydrogen depth profiling. Comments: 10 pages, 8 figures. Corrected typos in the abstract, table IV made more comprehensible. As accepted in Phys.Rev.C
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<extra_id_0> Simone <extra_id_1> slowest <extra_id_2> is frequently <extra_id_3> in inverse kinematics <extra_id_4> and 15N(p, \alpha \gamma)12C <extra_id_5> \gamma)12C have been determined <extra_id_6> are \omega \gamma = <extra_id_7> decay of <extra_id_8>
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Title: Quark nova inside supernova: Application to GRBs and XROsCategory: astro-ph.HE astro-ph.SRAuthors: Jan Staff, Rachid OuyedStudy Abstract: In this paper we consider <extra_id_0> occurring inside an exploding star. The quark nova ejecta will shock when interacting with the <extra_id_1> When this shock reaches the surface of the star, <extra_id_2> is radiated away. We suggest <extra_id_3> energy may be seen in X-rays, <extra_id_4> that this may explain some flares seen in the X-ray afterglow of long gamma ray bursts (GRBs). A quark <extra_id_5> exploding star need not be followed by a GRB, or the GRB may not be beamed towards us. However, the shock breakout is likely not beamed and could be seen even in the absence of a GRB. <extra_id_6> that XRO 080109 is such an event in which a quark nova occurs inside an exploding star. No GRB is formed, but the break out of the shock leads to the XRO. Comments: 13 pages, 3 figures, 1 table. To appear in Proceedings for "Compact stars in the QCD phase diagram II (CSQCD <extra_id_7> 20-24, 2009, KIAA at Peking University, <extra_id_8> R. China [http://vega.bac.pku.edu.cn/rxxu/csqcd.htm]
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<extra_id_0> a quark nova <extra_id_1> stellar envelope. <extra_id_2> the energy <extra_id_3> that this <extra_id_4> and show here <extra_id_5> nova inside an <extra_id_6> We suggest <extra_id_7> II), May <extra_id_8> Beijing - P. <extra_id_9>
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Title: Improved bounds on coloring of graphsCategory: math.COAuthors: Sokol <extra_id_0> Benedetto ScoppolaStudy Abstract: Given a graph $G$ <extra_id_1> <extra_id_2> $\Delta\ge 3$, we <extra_id_3> edge chromatic number $a'(G)$ of $G$ is such that $a'(G)\le\lceil 9.62 (\Delta-1)\rceil$. Moreover we prove <extra_id_4> \lceil 6.42(\Delta-1)\rceil$ if <extra_id_5> girth $g\ge 5\,$; $a'(G)\le \lceil5.77 (\Delta-1)\rc$ if $G$ has girth $g\ge 7$; <extra_id_6> $g\ge 53$; <extra_id_7> \lceil25.84\D\log\D(1+ 4.1/\log\D)\rceil$. We further prove that the acyclic (vertex) chromatic number $a(G)$ of $G$ is such that $a(G)\le \lc 6.59 \Delta^{4/3}+3.3\D\rc$. We also prove that the star-chromatic number $\chi_s(G)$ of $G$ is such that $\chi_s(G)\le \lc4.34\Delta^{3/2}+ 1.5\D\rc$. We finally prove that the $\b$-frugal chromatic number <extra_id_8> <extra_id_9> that $\chi^\b(G)\le \lc\max\{k_1(\b)\D,\; k_2(\b){\D^{1+1/\b}/ (\b!)^{1/\b}}\}\rc$, where $k_1(\b)$ and $k_2(\b)$ are decreasing functions of $\b$ such that $k_1(\b)\in[4, 6]$ and $k_2(\b)\in[2,5]$. To obtain these results we use an improved version of the Lov\'asz Local Lemma due to Bissacot, <extra_id_10> and Scoppola \cite{BFPS}. Comments: Introduction revised. Added references. Corrected typos. Proof of Theorem 2 (items c-f) written in more details
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<extra_id_0> Ndreca, Aldo Procacci, <extra_id_1> with maximum <extra_id_2> degree <extra_id_3> prove that the acyclic <extra_id_4> that: $a'(G)\le <extra_id_5> $G$ has <extra_id_6> $a'(G)\le \lc4.52(\D-1)\rc$ if <extra_id_7> $a'(G)\le \D+2\,$ if $g\ge <extra_id_8> $\chi^\b(G)$ of $G$ <extra_id_9> is such <extra_id_10> Fern\'andez, Procacci <extra_id_11>
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Title: A Theoretical Investigation on the Gamma-ray Burst Host GalaxiesCategory: astro-ph.HE astro-ph.COAuthors: J. MaoStudy Abstract: Long-duration gamma-ray bursts(LGRBs) are believed to be <extra_id_0> the star formation. We adopt a galactic evolution model, in which the star formation process inside the virialized dark halo at given redshift can be achieved. In this paper, <extra_id_1> galaxies are assumed to be the star-forming galaxies <extra_id_2> the small dark halos. The star formation rates(SFRs) in the host galaxies of <extra_id_3> been derived from our model with the galactic evolutionary time about a few times of $10^7$ yr and the dark halo mass of about $5\times 10^{11}M_\odot$. The related stellar masses, luminosities and metallicities of these hosts are estimated as well. We further calculate the X-ray and optical absorption of GRB afterglow emission. From our model calculation, at higher redshift, the <extra_id_4> galaxy is larger, the absorption <extra_id_5> optical band of GRB afterglow is stronger, in the condition that the dust and metal components are released locally, surrounding the GRB environment. These model predictions are compared with the {\it Swift} and other observational <extra_id_6> redshift $z<1$, as the merger and interaction of <extra_id_7> galaxies are involved, one monolithic physical process is not <extra_id_8> fully explain all <extra_id_9> observed phenomena. Comments: ApJ accepted, <extra_id_10> welcome
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<extra_id_0> linked with <extra_id_1> the gamma-ray burst(GRB) host <extra_id_2> within <extra_id_3> LGRBs at different redshifts have <extra_id_4> SFR of host <extra_id_5> in X-ray band and <extra_id_6> data. At lower <extra_id_7> some host <extra_id_8> sufficient to <extra_id_9> kinds of <extra_id_10> comments are <extra_id_11>
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<extra_id_0> molecular interstellar medium <extra_id_1> spectroscopyCategory: astro-ph.COAuthors: P. Panuzzo, N. Rangwala, A. Rykala, K. G. Isaak, J. Glenn, C. D. Wilson, R. Auld, M. Baes, <extra_id_2> Barlow, G. J. Bendo, J. J. Bock, A. <extra_id_3> <extra_id_4> N. Castro-Rodr\'iguez, P. <extra_id_5> S. Charlot, L. Ciesla, D. L. Clements, A. Cooray, <extra_id_6> L. Cortese, J. I. Davies, E. Dwek, S. A. Eales, D. Elbaz, T. Fulton, M. Galametz, F. Galliano, W. K. Gear, H. L. Gomez, M. Griffin, S. Hony, L. R. Levenson, N. Lu, S. Madden, B. O'Halloran, K. Okumura, S. Oliver, M. J. Page, A. Papageorgiou, T. J. Parkin, I. P\'erez-Fournon, M. Pohlen, E. T. Polehampton, E. E. Rigby, H. Roussel, N. <extra_id_7> M. Sauvage, B. Schulz, M. R. P. Schirm, M. W. L. Smith, L. Spinoglio, J. A. <extra_id_8> Symeonidis, B. Swinyard, M. Trichas, M. Vaccari, L. <extra_id_9> S. Wright, W. W. <extra_id_10> We present the observations of the starburst <extra_id_11> with the Herschel SPIRE Fourier Transform Spectrometer. The spectrum (194-671 {\mu}m) shows a prominent CO rotational ladder from J = 4-3 to 13-12 emitted by the central region of M82. The fundamental properties of the gas are well constrained by the high J lines observed for the first time. Radiative transfer modeling of these high-S/N 12CO and 13CO lines strongly indicates a very warm molecular gas component <extra_id_12> and pressure of ~3x10^6 K cm^-3, in good agreement with the H_2 rotational lines <extra_id_13> Spitzer and ISO. We suggest that this warm gas is heated by dissipation of turbulence in the interstellar medium (ISM) rather than X-rays or UV flux from the straburst. This paper illustrates the promise of <extra_id_14> FTS for <extra_id_15> of the ISM of nearby galaxies. Comments: 5 pages, 4 figures, Accepted for publication on the A&A Herschel Special Issue
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<extra_id_0> Title: Probing the <extra_id_1> of M82 with Herschel-SPIRE <extra_id_2> M. J. <extra_id_3> Boselli, M. <extra_id_4> Bradford, V. Buat, <extra_id_5> Chanial, <extra_id_6> D. Cormier, <extra_id_7> Sacchi, <extra_id_8> Stevens, S. Srinivasan, M. <extra_id_9> Vigroux, H. Wozniak, G. <extra_id_10> ZeilingerStudy Abstract: <extra_id_11> galaxy M82 taken <extra_id_12> at ~500 K <extra_id_13> measurements from <extra_id_14> the SPIRE <extra_id_15> the study <extra_id_16>
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Title: Chameleon Cosmology Model Describing the Phantom <extra_id_0> gr-qc astro-ph.CO hep-thAuthors: F. Cannata and A.Yu. KamenshchikStudy Abstract: An exact solution describing the evolution of the type Bang-to-Rip with the phantom divide line <extra_id_1> the Chameleon <extra_id_2> two independent functions of the scalar field. Comments: 9 pages
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<extra_id_0> Divide Line CrossingCategory: <extra_id_1> crossing is constructed in <extra_id_2> cosmology model, based on <extra_id_3>
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Title: Transcendental obstructions <extra_id_0> on general K3 surfacesCategory: math.AG math.NTAuthors: Brendan Hassett, Anthony V\'arilly-Alvarado, Patrick VarillyStudy Abstract: We construct an explicit K3 surface over the field of rational numbers that has geometric Picard rank one, and for which there is a transcendental Brauer-Manin obstruction to weak approximation. To do so, we exploit <extra_id_1> polarized K3 surfaces endowed with particular kinds of Brauer classes and cubic fourfolds. Comments: 24 pages, 3 figures, Magma scripts included at the end of the source file.
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<extra_id_0> to weak approximation <extra_id_1> the relationship between <extra_id_2>
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Title: Comment on "Dynamical mean field solution of the Bose-Hubbard model"Category: cond-mat.str-el cond-mat.quant-gasAuthors: K. Byczuk and D. VollhardtStudy Abstract: In their preprint Anders et al. [arXiv:1004.0510] propose a crucial modification of the Bosonic Dynamical Mean-Field Theory (B-DMFT) derived by us [Phys. Rev. B 77, 235106 (2008)]. Here we show that the modification consists of two steps which, in fact, cancel each <extra_id_0> self-consistency equations are <extra_id_1> ours. Comments: 2 pages, no figures
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<extra_id_0> other. Consequently their <extra_id_1> identical to <extra_id_2>
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Title: Approximate <extra_id_0> Emmanuel Breuillard, Ben Green, Terence TaoStudy Abstract: We establish various results on the structure of approximate subgroups in linear groups such as SL_n(k) that were previously announced by the authors. For example, generalising a result of Helfgott (who handled the cases n = 2 and 3), we show that any approximate subgroup of SL_n(F_q) which generates the group must be either very small or else nearly all of SL_n(F_q). The argument generalises to other absolutely almost simple connected (and non-commutative) algebraic groups G over a finite field k. In a <extra_id_1> paper, we will give applications of this result to the expansion properties <extra_id_2> Cayley graphs. Comments: 48 pages
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<extra_id_0> subgroups of linear groupsCategory: math.GRAuthors: <extra_id_1> subsequent <extra_id_2> of <extra_id_3>
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Title: Multiple critical point structure for chiral phase transition induced by charge neutrality and vector interactionCategory: hep-ph astro-ph.SRAuthors: Zhao Zhang, Teiji KunihiroStudy Abstract: The combined effect of the repulsive vector <extra_id_0> <extra_id_1> <extra_id_2> on the chiral phase transition is investigated by considering neutral color superconductivity. Under the charge-neutrality <extra_id_3> condensate, diquark condensate and <extra_id_4> number densities are obtained in two-plus-one-flavor Nambu-Jona-Lasinio model with the so called Kobayashi-Maskawa-'t Hooft term. We demonstrate that multiple chiral critical-point structures always exist in the Nambu-Jona-Lasinio model within the self-consistent mean-field approximation, and that the number of chiral critical points can vary from zero to four, which is dependent on the magnitudes of vector interaction and the diquark coupling. Comments: <extra_id_5> <extra_id_6> figure. To appear in Proceedings for "Compact stars in the QCD phase diagram II (CSQCD II), May 20-24, 2009, KIAA at Peking University, Beijing - P. R. China [http://vega.bac.pku.edu.cn/rxxu/csqcd.htm]
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<extra_id_0> interaction and the <extra_id_1> positive electric <extra_id_2> chemical potential <extra_id_3> constraint, the chiral <extra_id_4> quark <extra_id_5> 9 pages, 1 <extra_id_6> table, 1 <extra_id_7>
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Title: The absence of sub-minute periodicity in classical T Tauri starsCategory: astro-ph.SRAuthors: H. M. G\"unther, <extra_id_0> P. G. Hundertmark, H. Steinle, J. H. M. M. Schmitt, D. Buckley, S. Crawford, D. O'Donoghue <extra_id_1> <extra_id_2> Tauri stars (CTTS) are young, late-type objects, that still <extra_id_3> a circumstellar disk. Analytical treatments and numerical simulations predict instabilities of the accretion shock on the stellar surface. We <extra_id_4> for variability on timescales below a few minutes in the CTTS TW Hya and AA Tau. TW <extra_id_5> <extra_id_6> Southern African Large Telescope (SALT) in narrow-band filters around the Balmer jump. The observations were performed in slit mode, which provides a time resolution of about 0.1 s. <extra_id_7> we obtained <extra_id_8> a single photon-counting device with even better time <extra_id_9> Small-scale variability typically lasts <extra_id_10> seconds, however, no significant periodicity is detected. We place a 99 % confidence upper limit on the pulsed fraction <extra_id_11> The relative amplitude is below 0.001 for TW Hya in the frequency range 0.02-3 <extra_id_12> 340 nm filter and 0.1-3 Hz in the 380 nm filter. The corresponding value for AA Tau is an amplitude of <extra_id_13> The relevant timescales indicate that shock instabilites should not be seen directly in our optical <extra_id_14> observations, but the predicted <extra_id_15> induce observable variations in the reddening. We discuss how the magnetic <extra_id_16> stabilise the accretion shock. Comments: 8 pages, 9 figures, accepted by A&A
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<extra_id_0> N. Lewandowska, M. <extra_id_1> and P. VaisanenStudy Abstract: <extra_id_2> Classical T <extra_id_3> accrete matter from <extra_id_4> search <extra_id_5> Hya was observed with <extra_id_6> SALTICAM on the <extra_id_7> For AA Tau <extra_id_8> observations with OPTIMA, <extra_id_9> resolution. <extra_id_10> a few <extra_id_11> of the lightcurves. <extra_id_12> Hz in the <extra_id_13> 0.005 for 0.02-50 Hz. <extra_id_14> and UV <extra_id_15> oscialltions would <extra_id_16> field could <extra_id_17>
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Title: Towards a <extra_id_0> Network for AstronomyCategory: astro-ph.IMAuthors: Alberto Accomazzi, Michael J. Kurtz, Stephen S. MurrayStudy Abstract: Over the past decade, astronomers have been <extra_id_1> larger number of web-based applications and archives to conduct their research. However, despite the early success in creating links across projects and data centers, the promise of a single integrated digital library environment supporting e-science in astronomy has proven elusive. While some of the issues hampering progress in this area are of technical nature, others are rooted in existing policies which should be re-analyzed if further <extra_id_2> to be made in this area. This paper describes a proposal <extra_id_3> Astrophysics Data System <extra_id_4> <extra_id_5> in order to improve its role as one of the primary discovery portals for astronomers, focusing <extra_id_6> which could benefit from an increased level of involvement from the community, namely <extra_id_7> expose astronomy resources as linked data, and the harvesting of observational metadata. Comments: 6 <extra_id_8> of IAU Special Session 5, "Accelerating the Rate of Astronomical <extra_id_9> published in Proceedings of Science
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<extra_id_0> Resource-Centric Data <extra_id_1> using an increasingly <extra_id_2> rapid progress is <extra_id_3> that the NASA <extra_id_4> project has <extra_id_5> put forth <extra_id_6> on those aspects <extra_id_7> the effort to <extra_id_8> pages, 1 figure, proceedings <extra_id_9> Discovery." To be <extra_id_10>
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Title: Enhanced dust heating in the bulges of early-type spiral galaxiesCategory: astro-ph.COAuthors: C. W. Engelbracht, L. K. Hunt, R. A. Skibba, J. L. Hinz, D. Calzetti, <extra_id_0> Roussel, A. F. Crocker, K. A. Misselt, A. D. Bolatto, R. C. <extra_id_1> N. Appleton, L. Armus, P. Beir\~ao, B. R. Brandl, K. V. Croxall, D. A. Dale, B. T. Draine, G. Dumas, <extra_id_2> <extra_id_3> Groves, C.-N. Hao, B. D. Johnson, J. Koda, O. Krause, A. K. Leroy, S. E. Meidt, E. J. Murphy, N. Rahman, H.-W. Rix, K. M. <extra_id_4> <extra_id_5> T. Smith, S. Srinivasan, L. Vigroux, F. Walter, B. E. Warren, C. D. Wilson, M. G. Wolfire and S. ZibettiStudy Abstract: Stellar density and bar strength should affect the temperatures of the cool (T ~ 20-30 K) dust component in the inner <extra_id_6> which implies that the ratio of <extra_id_7> circumnuclear regions to the disk should depend on Hubble type. We investigate the differences <extra_id_8> dust temperatures in the central 3 kpc and disk of 13 nearby galaxies by fitting models to measurements between 70 and 500 microns. We <extra_id_9> to quantify temperature trends in nearby disk galaxies, with archival data from Spitzer/MIPS and new observations with Herschel/SPIRE, which were acquired during the first phases of <extra_id_10> observations for the KINGFISH (key <extra_id_11> galaxies: a far-infrared survey <extra_id_12> We fit single-temperature modified blackbodies to far-infrared and submillimeter measurements of the central and disk <extra_id_13> galaxies to determine the temperature of the component(s) emitting at those wavelengths. We present the ratio of central-region-to-disk-temperatures of the cool dust component of <extra_id_14> as a function of morphological type. We find a significant temperature gradient in the cool dust component in all galaxies, with a mean center-to-disk temperature ratio of 1.15 +/- 0.03. The cool dust temperatures in the central ~3 kpc of nearby galaxies are <extra_id_15> hotter for morphological types earlier than Sc, and only 9(+/-3)% hotter for <extra_id_16> types. The temperature ratio is also correlated with bar strength, with only strongly barred galaxies having a ratio over 1.2. The strong radiation field in the high stellar density of a galactic bulge tends to heat the cool dust component to higher temperatures, at least in early-type spirals with relatively large bulges, especially when paired with a strong bar. Comments: Accepted for publication on the A&A Herschel Special Issue
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<extra_id_0> K. D. Gordon, H. <extra_id_1> Kennicutt, P. <extra_id_2> A. Gil de <extra_id_3> Paz, B. <extra_id_4> Sandstrom, M. Sauvage, E. <extra_id_5> Schinnerer, J.-D. <extra_id_6> regions of galaxies, <extra_id_7> temperatures in the <extra_id_8> between cool <extra_id_9> attempt <extra_id_10> the Herschel <extra_id_11> insights in nearby <extra_id_12> with Herschel) sample. <extra_id_13> regions of <extra_id_14> 13 nearby galaxies <extra_id_15> 23(+/-3)% <extra_id_16> later <extra_id_17>
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Title: On <extra_id_0> holographyCategory: hep-phAuthors: V.A.RubakovStudy Abstract: We point <extra_id_1> there is a difference between the behavior of fermionic systems (and their holographic analogs) in a background axial vector field, on the one hand, <extra_id_2> at finite chiral chemical potential, on the other. In the former case, the electric current induced by constant background axial field $A_0$ and magnetic field ${\bf B}$ vanishes, while in the latter it is given by the anomaly-prescribed formula ${\bf j} = \frac{\mu_A}{2\pi^2}e^2 N_c {\bf B}$. Comments: 7 pages
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<extra_id_0> chiral magnetic effect and <extra_id_1> out that <extra_id_2> and <extra_id_3>
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Title: The Herschel Space <extra_id_0> in M81Category: astro-ph.COAuthors: G. J. Bendo, C. D. Wilson, M. Pohlen, M. Sauvage, R. Auld, M. Baes, M. J. Barlow, J. J. Bock, A. Boselli, M. Bradford, <extra_id_1> P. Chanial, S. Charlot, L. Ciesla, <extra_id_2> Cooray, D. Cormier, L. Cortese, J. I. Davies, E. Dwek, S. A. Eales, <extra_id_3> M. Galametz, F. Galliano, W. K. Gear, J. Glenn, H. L. Gomez, M. Griffin, S. <extra_id_4> G. Isaak, L. R. Levenson, N. Lu, S. Madden, B. O'Halloran, K. Okumura, S. Oliver, M. J. Page, P. Panuzzo, A. Papageorgiou, T. J. Parkin, I. Perez-Fournon, N. Rangwala, E. E. Rigby, H. Roussel, A. Rykala, N. Sacchi, B. Schulz, <extra_id_5> M. W. L. <extra_id_6> Spinoglio, J. A. <extra_id_7> Sundar, M. Symeonidis, M. Trichas, M. Vaccari, L. Vigroux, H. Wozniak, G. S. Wright, W. W. ZeilingerStudy Abstract: We use Herschel Space Observatory data to place observational constraints on the peak and Rayleigh-Jeans slope of dust emission observed at 70-500 microns <extra_id_8> spiral galaxy M81. We find that the ratios of wave bands between 160 and 500 microns are primarily dependent on radius but that the ratio of 70 to 160 micron emission shows no clear dependence on surface brightness or radius. These results along with analyses of the spectral energy distributions imply that the 160-500 micron emission traces 15-30 K dust heated by evolved stars in the bulge and disc whereas the 70 micron emission includes dust heated by the active galactic nucleus and young stars in star forming regions. Comments: Accepted for A & A Herschel special issue
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<extra_id_0> Observatory view of dust <extra_id_1> V. Buat, N. Castro-Rodriguez, <extra_id_2> D. L. Clements, A. <extra_id_3> D. Elbaz, <extra_id_4> Hony, K. <extra_id_5> M. R. P. Schirm, <extra_id_6> Smith, L. <extra_id_7> Stevens, S. <extra_id_8> in the nearby <extra_id_9>
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Title: SNIa photometric studies in SNLSCategory: astro-ph.COAuthors: N. Palanque-Delabrouille (on behalf of the SNLS collaboration)Study Abstract: The discovery of accelerated expansion using supernova surveys has been one of the most surprising discoveries in cosmology in the past ten years. Present and future surveys, among which SNLS, JDEM or LSST, are based on samples of a few hundreds to a million supernovae. The measurement of their spectroscopic redshifts to investigate dark energy properties is already by far the limiting aspect of such surveys. In this paper, I will discuss and illustrate with SNLS data an approach based solely on photometry to both select supernova candidates and determine their redshift. Comments: Proceedings for the Moriond 2010 Cosmology session, 4 pages, 3 figures
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<extra_id_0>
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Title: Abundance patterns of multiple populations in Globular Clusters: a <extra_id_0> model based on <extra_id_1> ejectaCategory: astro-ph.GAAuthors: <extra_id_2> Francesca D'Antona, Paolo Ventura, Enrico Vesperini and Stephen L. W. McMillanStudy Abstract: A large number of spectroscopic studies have provided evidence of the presence of multiple populations in globular clusters by revealing patterns in the stellar chemical abundances. This paper is aimed at studying the origin of these abundance patterns. We explore a <extra_id_3> which second generation (SG) stars form out of a mix of pristine gas <extra_id_4> first generation of asymptotic giant branch stars. We first study the <extra_id_5> by the spectroscopic data of SG stars in globular clusters on the chemical properties of the asymptotic and super asymptotic giant branch ejecta. With a simple one-zone chemical model, we then explore the formation of the SG population abundance patterns focussing our attention on the Na-O, Al-Mg anticorrelations and on the helium distribution function. We carry out a survey of models and explore the dependence of the final SG chemical properties on the key parameters affecting the gas dynamics and the SG formation process. Finally, we use our chemical evolution framework to build specific models for NGC 2808 and M4, two Galactic globular clusters which show different patterns in the Na-O and Mg-Al anticorrelation and have different helium distributions. We find that the amount of pristine gas involved in the formation of SG stars is a key parameter to fit the observed O-Na and Mg-Al patterns. The <extra_id_6> these models is in general good agreement with the observed one. Our models, by shedding light on the role of different parameters and their interplay in determining the final SG chemical properties, illustrate the basic ingredients, constraints and problems encountered in this self-enrichment scenario which must be addressed by more sophisticated chemical and hydrodynamic simulations. Comments: 19 <extra_id_7> <extra_id_8>
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<extra_id_0> chemical evolution <extra_id_1> yields from AGB <extra_id_2> Annibale D'Ercole, <extra_id_3> model in <extra_id_4> and ejecta of the <extra_id_5> constraints imposed <extra_id_6> helium distribution function for <extra_id_7> pages, 10 figures, <extra_id_8> MNRAS accepted <extra_id_9>
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Title: A probabilistic approach to the asymptotics of <extra_id_0> of the <extra_id_1> alternating subsequenceCategory: math.PR math.COAuthors: Christian Houdr\'e, Ricardo RestrepoStudy Abstract: Let $LA_{n}(\tau)$ be the length <extra_id_2> longest alternating subsequence of a uniform random permutation $\tau\in[n]$. Classical probabilistic <extra_id_3> used to rederive the asymptotic mean, variance and limiting law of $LA_{n}(\tau)$. Our methodology is robust enough to tackle similar problems for finite alphabet random words or even Markovian sequences in which case our results are mainly original. A sketch of how some cases of pattern restricted permutations can also be tackled with <extra_id_4> methods is finally presented. Comments: Final version with a new title and various extensions
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<extra_id_0> the length <extra_id_1> longest <extra_id_2> of the <extra_id_3> arguments are <extra_id_4> probabilistic <extra_id_5>
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Title: Tensors as module homomorphisms <extra_id_0> ringsCategory: math.NA cs.NA math.RAAuthors: Carmeliza Navasca, Michael <extra_id_1> Christino TamonStudy Abstract: Braman [B08] described a construction where third-order tensors are exactly the set of linear transformations acting on the set of matrices with vectors as scalars. This <extra_id_2> familiar notion that matrices form the set of all linear <extra_id_3> real-valued scalars. This result is based upon a circulant-based tensor multiplication due to Kilmer et al. [KMP08]. In this work, we generalize these observations further by viewing this construction in its natural framework of group rings.The circulant-based products arise as convolutions in these algebraic structures. Our generalization allows for any abelian group to replace the cyclic group, any commutative ring with identity to replace the <extra_id_4> an arbitrary order tensor to replace third-order tensors, provided the underlying ring is commutative. Comments: 11 pages, 4 figures.
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<extra_id_0> over group <extra_id_1> Opperman, Timothy Penderghest, <extra_id_2> extends the <extra_id_3> transformations over vectors with <extra_id_4> field of real numbers, and <extra_id_5>
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Title: Recent Results of Fluctuation and Correlation Studies <extra_id_0> STAR ExperimentCategory: nucl-exAuthors: Terence J Tarnowsky, (for the STAR Collaboration)Study Abstract: Enhanced fluctuations and correlations have been observed in the phase transitions of many systems. Their appearance at the predicted QCD phase transition (especially near the expected critical point) may provide insight into the <extra_id_1> the phase transition. Recent <extra_id_2> STAR experiment will be presented <extra_id_3> a focus on particle ratio (K/$\pi$ and p/$\pi$) fluctuations, forward-backward multiplicity correlations, and balance functions. Also discussed will be possibilities for measuring these correlations and <extra_id_4> the recently initiated beam energy scan at RHIC. Comments: 6 pages, 3 <extra_id_5> be published in the proceedings of WWND 2010, Ocho Rios, Jamaica, January 20010, Journal of Physics: Conference Series.
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<extra_id_0> from the <extra_id_1> nature of <extra_id_2> results from the <extra_id_3> with <extra_id_4> fluctuations in <extra_id_5> figures. To <extra_id_6>
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Title: Deciphering the minimum of energy of <extra_id_0> technicolor modelsCategory: hep-phAuthors: A. Doff and A. A. NataleStudy Abstract: There are quasi-conformal theories, like the Minimal <extra_id_1> models, which may break dynamically the gauge symmetry of the Standard Model and at the same time are compatible with electroweak precision data. The main characteristic of this type of models is their fermionic content in one or more higher dimensional representations, therefore it is not immediate to know which model leads to the most attractive channel or the minimum vacuum energy state. We discuss the effective potential for composite operators for these models, verifying that their vacuum energy <extra_id_2> different, with the Ultraminimal model having a deeper minimum of energy. Comments: 4 pages, 2 figures, published version.
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<extra_id_0> some walking <extra_id_1> and Ultraminimal Technicolor <extra_id_2> values are <extra_id_3>
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Title: Ionospheric Power-Spectrum Tomography in Radio InterferometryCategory: astro-ph.IM astro-ph.CO astro-ph.EP astro-ph.GA astro-ph.SRAuthors: L.V.E. Koopmans (Kapteyn Astronomical Institute)Study Abstract: A tomographic method is described to quantify the three-dimensional power-spectrum of <extra_id_0> electron-density fluctuations based on radio-interferometric observations by a two-dimensional planar array. The method is valid to first-order Born approximation and might be applicable to correct observed visibilities for phase variations due to the imprint of the full three-dimensional ionosphere. It is shown that not the ionospheric electron density distribution is the primary structure <extra_id_1> interferometry, but its autocorrelation function or equivalent its power-spectrum. An exact mathematical expression is derived that provides the three dimensional <extra_id_2> the ionospheric electron-density fluctuations directly from <extra_id_3> scattered intensity field and an incident intensity field convolved with a complex unit <extra_id_4> that depends on the w-term and is defined on the full sky pupil plane. <extra_id_5> a small field of view, the method reduces to the single phase <extra_id_6> Tomographic self-calibration can become important in high-dynamic range observations at <extra_id_7> with wide-field antenna interferometers, because a three-dimensional ionosphere causes a spatially varying convolution of the sky, whereas a single phase screen results in a spatially invariant convolution. A thick ionosphere can therefore not be approximated by a single phase screen without introducing <extra_id_8> the calibration process. By applying a Radon projection and the Fourier projection-slice theorem, <extra_id_9> shown that the phase-screen approach in three dimensions is identical to <extra_id_10> Finally we suggest that residual speckle can cause <extra_id_11> diffuse intensity halo around sources, due to uncorrectable ionospheric phase fluctuations in the short <extra_id_12> could pose a fundamental limit on the dynamic range in long-integration images. Comments: 8 pages; Accepted for publication in ApJ
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<extra_id_0> the ionospheric <extra_id_1> to model in <extra_id_2> power-spectrum of <extra_id_3> a rescaled <extra_id_4> phasor <extra_id_5> In the limit of <extra_id_6> screen approximation. <extra_id_7> low radio frequencies <extra_id_8> errors in <extra_id_9> it is <extra_id_10> the tomographic method. <extra_id_11> a <extra_id_12> integrations, which <extra_id_13>
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Title: The ABC of Digital Business EcosystemsCategory: cs.CYAuthors: Jo Stanley and Gerard BriscoeStudy Abstract: The European Commission has the power to inspire, initiate and sponsor huge transnational projects to an extent impossible for <extra_id_0> entities. <extra_id_1> projects can address universal themes and develop well-being models that <extra_id_2> diversity of societies <extra_id_3> is a universal fact that SMEs in all countries provide a substantial proportion of total employment, and <extra_id_4> nation's innovative activity. Yet these smaller companies struggle in global markets on a far from level playing field, where large companies have distinct advantages. To redress this imbalance the <extra_id_5> it as a priority to improve the trading capability of the Small and Medium-sized Enterprises (SMEs), and perceived digital platforms as the modern means to <extra_id_6> that the best operational model for a vibrant Web2.0-based Internet services industry would be by analogy to well-performing biological ecosystems. Open Source Software is adopted in <extra_id_7> as the best support for sustainability of such complex electronic webs, since it minimises interoperability problems, enables <extra_id_8> access for cheaper in-house modification or development of systems, and reduces both capital and operating expenditure. Comments: 24 pages, 5 figures
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<extra_id_0> most other <extra_id_1> These <extra_id_2> are valuable across a <extra_id_3> and economies. It <extra_id_4> conduct much of a <extra_id_5> Commission saw <extra_id_6> this end. They considered <extra_id_7> the DBE/OPAALS projects <extra_id_8> code <extra_id_9>
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Title: The graded structure of Leavitt Path algebrasCategory: math.RAAuthors: R. HazratStudy Abstract: Leavitt path algebras associate to directed graphs a $\mathbb Z$-graded algebra and in their simplest form recover the Leavitt algebras $L(1,k)$. In this note, we first study this $\mathbb Z$-grading and characterize the ($\mathbb Z$-graded) structure of Leavitt path algebras, associated to finite acyclic graphs, $C_n$-comet and multi-headed graphs. The last two type are examples of <extra_id_0> path algebras are strongly <extra_id_1> Leavitt path algebras <extra_id_2> graded, along the way obtaining classes of algebras which are group rings or crossed-products. In an attempt to generalize the <extra_id_3> weighted Leavitt path algebras associated to <extra_id_4> graphs which have natural $\textstyle{\bigoplus} \mathbb Z$-grading and in their simplest form recover the Leavitt algebras $L(n,k)$. We then establish some basic <extra_id_5> <extra_id_6> 32 pages, (even more) polishing
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<extra_id_0> graphs whose Leavitt <extra_id_1> graded. We characterize <extra_id_2> which are strongly <extra_id_3> grading, we introduce <extra_id_4> directed weighted <extra_id_5> properties of these <extra_id_6> algebras. Comments: <extra_id_7>
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Title: The Invariant Measures of some Infinite Interval Exchange MapsCategory: math.DSAuthors: W. Patrick HooperStudy Abstract: We classify the locally finite ergodic invariant measures of <extra_id_0> interval exchange transformations (IETs). These transformations <extra_id_1> from return maps of the straight-line flow on <extra_id_2> surfaces, and the study of the invariant measures for these IETs <extra_id_3> the study of invariant measures for the straight-line flow in some direction on these translation surfaces. For the surfaces and directions <extra_id_4> apply, we can characterize the locally finite ergodic invariant measures of the straight-line flow in a set of directions of Hausdorff dimension larger than 1/2. We promote this <extra_id_5> in some cases. For instance, when the surfaces admit a cocompact action by a nilpotent group, we prove each ergodic invariant measure for the straight-line flow is a Maharam measure, and we <extra_id_6> precisely which Maharam measures arise. When the surfaces under consideration are finite area, the straight-line flows in the directions we understand are uniquely ergodic. Our methods apply <extra_id_7> surfaces admitting multi-twists in a pair of cylinder decompositions in non-parallel directions. Comments: <extra_id_8> Minor improvements
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<extra_id_0> certain infinite <extra_id_1> naturally arise <extra_id_2> certain translation <extra_id_3> is equivalent to <extra_id_4> for which our methods <extra_id_5> characterization to a classification <extra_id_6> describe <extra_id_7> to translation <extra_id_8> 107 pages, 11 figures. <extra_id_9>
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Title: Complexity analysis of Klein-Gordon single-particle systemsCategory: quant-ph math-ph math.MPAuthors: Daniel Manzano, Sheila L\'opez-Rosa and Jes\'us S\'anchez-DehesaStudy Abstract: The Fisher-Shannon complexity is used to quantitatively estimate the contribution of relativistic effects to on the internal disorder of Klein-Gordon single-particle Coulomb systems which is manifest in <extra_id_0> variety of three-dimensional geometries of its corresponding quantum-mechanical probability <extra_id_1> It is observed that, contrary to the non-relativistic case, the Fisher-Shannon complexity of these relativistic systems does depend on the potential strength (nuclear charge). This is numerically illustrated for pionic atoms. Moreover, its <extra_id_2> quantum numbers (n, l, m) is analysed in various ground and excited states. It is found <extra_id_3> enhance when n and/or l are decreasing. Comments: 4 pages, 3 figures, Accepted in EPL (Europhysics Letters)
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<extra_id_0> the rich <extra_id_1> density. <extra_id_2> variation with the <extra_id_3> that the relativistic effects <extra_id_4>
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Title: Cloud Computing: Exploring the scopeCategory: cs.DCAuthors: <extra_id_0> Pandey, Ankit <extra_id_1> Kr Maurya, Upendra Kushwaha, Dr. Madhvendra Mishra, Vijayshree TiwariStudy Abstract: Cloud computing <extra_id_2> shift to overall IT solutions while raising the accessibility, scalability and effectiveness <extra_id_3> enabling technologies. However, migrated <extra_id_4> platforms and services cost benefits as well as performances are neither clear nor summarized. Globalization and the recessionary economic times have not only raised the bar of a better IT delivery models <extra_id_5> given access to technology enabled services via internet. Cloud computing <extra_id_6> terms of lean <extra_id_7> methodologies that can minimize the operational cost by using the third party based IT capabilities, as a service. It will not only increase the ROI but will also help in lowering the total cost of ownership. In this paper <extra_id_8> tried to compare the cloud computing cost benefits with the actual premise cost which an organization incurs normally. <extra_id_9> the cost benefits, many IT professional <extra_id_10> latest model i.e. "cloud computing" has risks and security concerns. This report demonstrates how to answer <extra_id_11> questions: (1) Idea behind cloud computing. (2) Monetary cost benefits of using <extra_id_12> to traditional premise computing. (3) What are the various security issues? We have <extra_id_13> find out the cost benefit <extra_id_14> the <extra_id_15> <extra_id_16> the prevalent premise <extra_id_17> pages, 7 figures, Paper accepted for the <extra_id_18> Conference on <extra_id_19> Applications (ICICCA 2010)
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<extra_id_0> Abhinav Pandey, Akash <extra_id_1> Tandon, Brajesh <extra_id_2> refers to a paradigm <extra_id_3> through its <extra_id_4> cloud <extra_id_5> but also have <extra_id_6> has vast potential in <extra_id_7> Retail <extra_id_8> we have <extra_id_9> However, in spite of <extra_id_10> believe that the <extra_id_11> the following <extra_id_12> cloud with respect <extra_id_13> tried to <extra_id_14> by comparing <extra_id_15> Microsoft Azure cloud <extra_id_16> cost with <extra_id_17> cost. Comments: 9 <extra_id_18> 2010 International <extra_id_19> Informatics, Cybernetics, and Computer <extra_id_20>
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Title: <extra_id_0> the specific heat measurements for <extra_id_1> Adel Benlagra and <extra_id_2> P\'epinStudy Abstract: Recently, attention has been given to a system of He$^3$ bi-layers where a quantum <extra_id_3> to the one in heavy fermion compounds has been observed <extra_id_4> 92007)] In our previous analysis [Phys. Rev. B 79, 045112 (2007)], based on the Kondo breakdown scenario, we addressed successfully most of the features <extra_id_5> in that experiment. Here, we consider the activation energy $\Delta$ observed experimentally in the specific heat measurements at low temperatures in the heavy Fermi liquid phase. Within our previous study of this system, this is identified with the <extra_id_6> when the <extra_id_7> is emptied due to a strong hybridization between the nearly localized <extra_id_8> the fluid second one. We discuss the successes and limitations of our approach. An <extra_id_9> is proposed. Comments: 6 pages, 6 figures - replaced <extra_id_10> published version
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<extra_id_0> Activation gap in <extra_id_1> He$^3$ bi-layersCategory: cond-mat.str-elAuthors: Adam Ran\c{c}on-Schweiger, <extra_id_2> Catherine <extra_id_3> criticality similar <extra_id_4> [Science 317, 1356 <extra_id_5> observed <extra_id_6> gap opening <extra_id_7> upper hybridized band <extra_id_8> first layer and <extra_id_9> additional prediction <extra_id_10> with the <extra_id_11>
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Title: Reentrant transition of bosons in a quasiperiodic potentialCategory: cond-mat.quant-gasAuthors: A. Cetoli, E. LundhStudy Abstract: We investigate the behavior of a <extra_id_0> of Bose-Einstein <extra_id_1> described by means of a Bose-Hubbard Hamiltonian. Using a Wannier function expansion for the wavefunction in each tube, we compute the Bose-Hubbard parameters related to two different longitudinal potentials, periodic and quasiperiodic. We predict that - upon increasing the external potential strength along the direction of the tubes - the condensate can experience a reentrant <extra_id_2> Mott insulating phase and the superfluid one. Comments: Accepted for publication in EPL
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<extra_id_0> two dimensional array <extra_id_1> condensate tubes <extra_id_2> transition between a <extra_id_3>
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Title: Dilatancy transition in a granular modelCategory: cond-mat.softAuthors: David Aristoff, Charles RadinStudy Abstract: We introduce a model of granular matter and use a stress ensemble to <extra_id_0> Carlo simulation shows the model to exhibit a second order phase transition, associated with the onset of dilatancy. <extra_id_1> versions can be obtained from: http://www.ma.utexas.edu/users/radin/papers/shear2.pdf
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<extra_id_0> analyze shearing. Monte <extra_id_1> Comments: Future <extra_id_2>
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Title: Topics in Lattice QCD and <extra_id_0> TheoryCategory: hep-lat nucl-thAuthors: Michael I. BuchoffStudy Abstract: Effective field theories provide <extra_id_1> categorizing <extra_id_2> effects of a high-energy fundamental theory in terms of the low-energy degrees of freedom. This process has been well established in mapping the fundamental <extra_id_3> QCD in <extra_id_4> degrees of freedom, which allows for quantitative connections and predictions between hardronic <extra_id_5> more direct approach to performing the non-perturbative QCD calculations is through lattice QCD. These computationally intensive calculations approximate continuum physics with a discretized lattice to extract hadronic phenomena from first principles. However, as in any approximation, <extra_id_6> systematic errors between <extra_id_7> calculation and actual <extra_id_8> To account for these systematic effects in terms of hadronic interactions, effective field theory proves to be useful. However, the fundamental theory <extra_id_9> is lattice QCD, as opposed to the usual continuum QCD. <extra_id_10> work, the basics of this process are outlined, and multiple original calculations are presented: effective field theory for anisotropic lattices, I=2 $\pi\pi$ scattering for isotropic, anisotropic, and twisted mass lattices. Additionally, a usage of effective field theories and the employment of an isospin chemical potential on the lattice is proposed to extract several computationally difficult scattering parameters. Lastly, recently proposed local, chiral lattice actions are analyzed in the framework of effective field theory, which illuminates various challenges <extra_id_11> actions. Comments: Ph.D Dissertation, 86 pages, 18 figures
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<extra_id_0> Effective Field <extra_id_1> a formalism for <extra_id_2> low-energy <extra_id_3> theory of <extra_id_4> terms of the hadronic <extra_id_5> observables. A <extra_id_6> there are multiple <extra_id_7> lattice QCD <extra_id_8> hardronic phenomena. <extra_id_9> of interest here <extra_id_10> In this <extra_id_11> in simulating such <extra_id_12>
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Title: LanHEP - a package for automatic generation <extra_id_0> rules from the Lagrangian. Updated version 3.1Category: hep-phAuthors: A. SemenovStudy Abstract: We present a new version 3.1 of the LanHEP software package. New features of the program include tools for the models with <extra_id_1> the particle classes for FeynArts output and using templates with LanHEP <extra_id_2> 4 pages
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<extra_id_0> of Feynman <extra_id_1> extra dimensions, implementation of <extra_id_2> statements. Comments: <extra_id_3>
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Title: Impulse approximation in the n p --> d pi^0 reaction reexaminedCategory: nucl-thAuthors: Daniel R. Bolton and Gerald A. MillerStudy Abstract: The impulse approximation (one-body operator) in the n <extra_id_0> --> d pi^0 reaction is reexamined <extra_id_1> of reducibility and recoil corrections. An inconsistency when one pion exchange is included in the production operator is demonstrated and then resolved via the introduction of "wave function corrections" which nearly vanish for static nucleon propagators. Inclusion of the recoil corrections to the nucleon propagators is found to change the magnitude and sign of the impulse production amplitude, worsening agreement with the experimental cross section by approximately 30%. A cutoff is used to account <extra_id_2> of the external wave functions, and is found to have a significant impact up to approximately 2.5 GeV. Comments: Published version
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<extra_id_0> p <extra_id_1> with emphasis on the issues <extra_id_2> for the phenomenological nature <extra_id_3>
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Title: Dynamical Chern-Simons modified gravity and Friedmann-Robertson-Walker metricCategory: hep-th gr-qcAuthors: C. Furtado, J. R. Nascimento, A. Yu. Petrov, A. F. SantosStudy Abstract: We study the conditions <extra_id_0> the Friedmann-Robertson-Walker (FRW) metric with <extra_id_1> Chern-Simons modified gravity. It turns out to be that in this situation the accelerated expansion <extra_id_2> the Universe takes place, with the time dependence of the scale factor turns out to be similar to the case of presence of the Chaplygin gas. Also we found that this modification changes the total density of the Universe and therefore gives a nontrivial <extra_id_3> a cosmological scenario. Comments: 11 pages, revised version, new material added
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<extra_id_0> for the consistency of <extra_id_1> the dynamical <extra_id_2> of <extra_id_3> impact to <extra_id_4>
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Title: Characterisation of 15 overlooked Ruprecht clusters with ages within 400Myr and 3GyrCategory: astro-ph.GAAuthors: Charles Bonatto and Eduardo BicaStudy Abstract: We <extra_id_0> and photometric parameters of 15 overlooked Ruprecht (hereafter Ru) star clusters by means of <extra_id_1> and field-star decontamination. Ru\,1, <extra_id_2> 23, 26, 27, 34, 35, 37, 41, 54, 60, 63, 66, and 152 are located in the third Galactic quadrant, while Ru\,174 is in the first. With <extra_id_3> by the field-decontaminated colour-magnitude diagrams (CMDs) and <extra_id_4> (RDPs), we derive ages in the range 400\,Myr --- 1\,Gyr, except for the older Ru\,37, with <extra_id_5> the Sun are within $\rm1.5\la\ds(kpc)\la8.0$. The RDPs are well-defined and can be described by a King-like profile for most of the radial range, except for Ru\,23, 27, 41, 63, and 174, which present a conspicuous stellar density <extra_id_6> central region. The clusters dwell between (or close to) the Perseus and Sagittarius-Carina arms. We derive evidence in favour of cluster size increasing with distance to the Galactic plane ($\zgc$), which is consistent with a low frequency of tidal stress associated with high-$|\zgc|$ regions. The <extra_id_7> rather faint even in the near-infrared, with apparent integrated \jj\ magnitudes within $6.4\la m_J\la9.8$, while their absolute magnitudes are $-6.6\la M_J\la-2.6$. Extrapolation of the relation between $M_V$ and $M_J$, derived <extra_id_8> that they are low-luminosity optical clusters, with $-5\la M_V\la-1$. Comments: The paper contains 11 <extra_id_9> Accepted by MNRAS.
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<extra_id_0> derive fundamental, structural, <extra_id_1> 2MASS photometry <extra_id_2> 10, <extra_id_3> the constraints imposed <extra_id_4> stellar radial density profiles <extra_id_5> $\sim3$\,Gyr. Distances from <extra_id_6> excess in the <extra_id_7> clusters are <extra_id_8> for globular clusters, suggests <extra_id_9> figures and 3 tables. <extra_id_10>
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Title: Spin susceptibility of interacting two-dimensional electrons in the presence of spin-orbit couplingCategory: <extra_id_0> Dmitrii L. Maslov, and Daniel LossStudy Abstract: A long-range interaction via virtual particle-hole pairs between Fermi-liquid quasiparticles <extra_id_1> a nonanalytic behavior of the spin susceptibility $\chi$ as a function of the temperature ($T$), magnetic field ($\mathbf{B}$), and wavenumber. In this paper, we study the effect of the Rashba spin-orbit interaction (SOI) on the nonanalytic behavior of $\chi$ for a two-dimensional electron liquid. Although the SOI breaks the SU(2) symmetry, it does not eliminate nonanalyticity but rather makes it anisotropic: while the linear scaling of $\chi_{zz}$ with <extra_id_2> saturates at the <extra_id_3> set by the SOI, that of $\chi_{xx}$ ($=\chi_{yy}$) continues through <extra_id_4> until <extra_id_5> interaction in the <extra_id_6> important. We show that the Renormalization Group flow in the Cooper channel has a non-trivial fixed point, and study the consequences of this fixed point for the nonanalytic behavior of $\chi$. An immediate <extra_id_7> SOI-induced anisotropy in the nonanalytic behavior of $\chi$ is a possible instability of a second-order ferromagnetic quantum phase transition with respect to a first-order transition to an XY ferromagnetic state. Comments: 34 pages, 12 figures
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<extra_id_0> cond-mat.mes-hall cond-mat.str-elAuthors: Robert Andrzej Zak, <extra_id_1> leads to <extra_id_2> $T$ and $|\mathbf{B}|$ <extra_id_3> energy scale <extra_id_4> this energy scale, <extra_id_5> renormalization of the electron-electron <extra_id_6> Cooper channel becomes <extra_id_7> consequence of <extra_id_8>
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Title: Dimensions of l^p-cohomology groupsCategory: math.FA math.GRAuthors: Mark S. Grinshpon, Peter A. Linnell, Michael J. PulsStudy Abstract: Let G be an infinite discrete group of type FP-infinity and let p>1 be a <extra_id_0> We prove that the l^p-homology and <extra_id_1> G are either 0 or infinite dimensional. We also show that the cardinality of the p-harmonic boundary of a finitely generated group is either 0, 1, or infinity. <extra_id_2> pages
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<extra_id_0> real number. <extra_id_1> cohomology groups of <extra_id_2> Comments: 9 <extra_id_3>
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Title: Analytical and numerical study of trapped strongly correlated bosons in two- <extra_id_0> Itay Hen and Marcos RigolStudy Abstract: We study <extra_id_1> properties of trapped inhomogeneous systems of hardcore bosons in two- and three-dimensional lattices. We obtain our results both numerically, using quantum Monte Carlo techniques, and via several analytical approximation schemes, such as the Gutzwiller-mean-field approach, a cluster-mean-field method and a spin-wave analysis which takes quantum fluctuations <extra_id_2> first study the homogeneous case, for which simple analytical expressions are obtained for all observables of <extra_id_3> the <extra_id_4> <extra_id_5> obtain the <extra_id_6> of <extra_id_7> with other thermodynamic properties such as the free energy, kinetic energy, superfluid density, condensate fraction and compressibility. <extra_id_8> of a trap, superfluid and insulating domains coexist in the system. We show that the spin-wave-based method reproduces the quantum Monte-Carlo results for global as well as for local quantities with a high degree of <extra_id_9> discuss the validity of the local <extra_id_10> those systems. Our analysis can <extra_id_11> describe bosons in optical lattices where the onsite interaction U is much larger than the hopping amplitude t. Comments: 14 pages, 14 figures
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<extra_id_0> and three-dimensional latticesCategory: cond-mat.quant-gasAuthors: <extra_id_1> the ground-state <extra_id_2> into account. We <extra_id_3> interest, and compare <extra_id_4> results with the <extra_id_5> numerical ones. We <extra_id_6> equation of state <extra_id_7> the system along <extra_id_8> In the presence <extra_id_9> accuracy. We also <extra_id_10> density approximation in <extra_id_11> be used to <extra_id_12>
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Title: First detection of the Methylidyne <extra_id_0> line with <extra_id_1> astro-ph.GAAuthors: D. A. Naylor, E. Dartois, E. Habart, A. Abergel, J.-P. Baluteau, S.C. <extra_id_2> Polehampton, P. Ade, L. D. Anderson, P. Andr\'e, H. Arab, J.-P. Bernard, K. Blagrave, <extra_id_3> M. Cohen, M. Compi\`egne, P. Cox, G. Davis, R. Emery, T. Fulton, C. Gry, M. Huang, <extra_id_4> M. Kirk, G. Lagache, T. Lim, S. Madden, G. Makiwa, P. Martin, M.-A. Miville-Desch\^enes, S. Molinari, H. Moseley, F. Motte, K. <extra_id_5> J. A. Rod\'on, D. Russeil, P. <extra_id_6> Spencer, B. Swinyard, D. Ward-Thompson, G. J. White, A. ZavagnoStudy Abstract: Aims. To follow the species chemistry arising in diverse sources of the Galaxy with Herschel. Methods. SPIRE FTS sparse sampled maps of the Orion bar & compact HII regions G29.96-0.02 and G32.80+0.19 have been analyzed. Results. Beyond <extra_id_7> atomic and molecular lines detected in the high-resolution <extra_id_8> with the FTS of SPIRE in <extra_id_9> Bar, one emission line is found to lie at the <extra_id_10> of the fundamental rotational transition of CH+ as measured precisely in the laboratory (Pearson & Drouion 2006). This coincidence suggests that it is the first detection of the fundamental rotational transition of CH+. This claim is strengthened by the observation of the lambda doublet transitions arising from its relative, CH, which are also observed in the same <extra_id_11> The broad spectral coverage of the SPIRE FTS <extra_id_12> simultaneous measurement of these closely related chemically species, under the same observing conditions. The importance of <extra_id_13> discussed and a comparison with results obtained from models of <extra_id_14> Region (PDR) of Orion are presented. The CH+ line also appears in absorption in the spectra of the two galactic compact HII regions G29.96-0.02 and G32.80+0.19, which is likely due to the presence <extra_id_15> CH+ in the the Cold Neutral Medium of the galactic plane. These detections will shed light on the formation processes and <extra_id_16> CH+, which are still outstanding questions in astrophysics. Comments: Accepted for publication in the A&A Herschel first results Special Issue
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<extra_id_0> cation (CH+) fundamental rotational <extra_id_1> the Herschel/SPIRE FTSCategory: <extra_id_2> Jones, E. <extra_id_3> F. Boulanger, <extra_id_4> C. Joblin, J. <extra_id_5> Okumura, D. Pinheiro-Gocalvez, <extra_id_6> Saraceno, S. Sidher, L. <extra_id_7> the wealth of <extra_id_8> spectra obtained <extra_id_9> the Orion <extra_id_10> position <extra_id_11> spectrum. <extra_id_12> allows for the <extra_id_13> these lines are <extra_id_14> the Photon Dominated <extra_id_15> of <extra_id_16> on the existence of <extra_id_17>
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Title: Prediction with Expert Advice under Discounted LossCategory: <extra_id_0> Alexey <extra_id_1> and Fedor <extra_id_2> study prediction with expert advice in the setting where the losses are <extra_id_3> with some discounting---the impact of old losses may gradually <extra_id_4> the Aggregating Algorithm and the Aggregating Algorithm for Regression to this case, propose a suitable new variant of exponential weights algorithm, and prove respective loss bounds. Comments: 26 pages; expanded (2 remarks -> theorems), some misprints corrected
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<extra_id_0> cs.LGAuthors: <extra_id_1> Chernov <extra_id_2> ZhdanovStudy Abstract: We <extra_id_3> accumulated <extra_id_4> vanish. We generalize <extra_id_5>
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Title: On the complement of the dense <extra_id_0> quiver of type $\Aa$Category: math.RTAuthors: Karin Baur, Lutz HilleStudy Abstract: Let $\Aa_t$ be the directed quiver of type $\Aa$ with $t$ vertices. For each dimension vector $d$ there is a dense orbit in <extra_id_1> representation space. The principal aim of this note <extra_id_2> use just rank conditions to define the irreducible components in the complement of the dense orbit. Then we compare this result with already <extra_id_3> Knight and Zelevinsky, and by Ringel. Moreover, we compare <extra_id_4> fan associated to the quiver $\Aa$ and derive a new formula for the number of orbits using nilpotent classes. In the complement <extra_id_5> orbit we determine the irreducible components and their codimension. Finally, we consider several particular examples. Comments: 16 pages, 9 figures
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<extra_id_0> orbit for a <extra_id_1> the corresponding <extra_id_2> is to <extra_id_3> existing ones by <extra_id_4> with the <extra_id_5> of the dense <extra_id_6>
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Title: A Naturally Minute Quantum Correction to the Cosmological Constant Descended from the HierarchyCategory: hep-th astro-ph.COAuthors: Shu-Heng Shao and Pisin ChenStudy Abstract: We demonstrate that an extremely small but positive quantum correction, or the Casimir energy, to the cosmological constant can arise from a massive bulk fermion field in the Randall-Sundrum model. Specifically, a cosmological constant doubly descended from the Planck-electroweak hierarchy and as minute as the observed dark energy scale can be naturally achieved without fine-tuning of the bulk fermion mass. To ensure the stabilization of the system, we discuss two stabilization mechanisms under <extra_id_0> It is found that the Goldberger-Wise <extra_id_1> can be successfully introduced in the <extra_id_2> bulk fermion, without spoiling the smallness of the quantum correction. Comments: 5 <extra_id_3>
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<extra_id_0> this setup. <extra_id_1> mechanism <extra_id_2> presence of a massive <extra_id_3> pages <extra_id_4>
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Title: PSpectRe: A Pseudo-Spectral Code for (P)reheatingCategory: astro-ph.CO gr-qc hep-ph hep-thAuthors: Richard Easther, Hal Finkel, Nathaniel RothStudy Abstract: PSpectRe is a C++ program that uses Fourier-space pseudo-spectral methods to evolve interacting scalar fields in an expanding universe. PSpectRe is optimized for the analysis of parametric resonance in the post-inflationary universe, and provides an alternative to <extra_id_0> such as Defrost and LatticeEasy. PSpectRe has both second- (Velocity-Verlet) and fourth-order (Runge-Kutta) time integrators. Given the same <extra_id_1> spatial points and/or momentum modes, PSpectRe is not significantly slower than finite differencing codes, despite the need <extra_id_2> multiple Fourier transforms at each timestep, and exhibits excellent energy conservation. Further, by computing the post-resonance equation of state, we <extra_id_3> some circumstances PSpectRe obtains <extra_id_4> results while using substantially fewer points <extra_id_5> a finite differencing code. PSpectRe is designed to be easily extended to other problems in early-universe cosmology, including the generation of gravitational <extra_id_6> during phase transitions and pre-inflationary bubble collisions. Specific applications of this code will be pursued in future work. Comments: 22 pages; source code for PSpectRe <extra_id_7> Typos fixed, minor improvements to wording; v3 updated as per referee comments
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<extra_id_0> finite differencing codes, <extra_id_1> number of <extra_id_2> for <extra_id_3> show that in <extra_id_4> reliable <extra_id_5> than <extra_id_6> waves <extra_id_7> available: http://easther.physics.yale.edu v2 <extra_id_8>
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Title: Fast Mid-IR Flashes Detected <extra_id_0> Small Solar X-Ray BurstsCategory: astro-ph.SRAuthors: Marta <extra_id_1> Cassiano, Pierre Kaufmann, <extra_id_2> Amauri S. Kudaka, <extra_id_3> Godoy, Pablo Pereyra, Arline M. Melo, Hugo LevatoStudy <extra_id_4> in the mid-infrared <extra_id_5> carried out with cadence of 5 frames per second, in December 2007. Rapid small heated sources, with typical duration of the order of seconds, were found on the bright plage-like areas around sunspots, in association with relatively weak GOES soft X-ray bursts. This work presents the analysis of fast mid-infrared flashes detected during a GOES B2.0-class event <extra_id_6> 10 December 2007, beginning at about 10:40 UT. Rapid brightness temperature enhancements of 0.5 to 2.0 K were detected at the Earth by a microbolometer array, using a telescope <extra_id_7> cm diameter aperture producing a diffraction limited field-of-view of 25 arcsec. <extra_id_8> <extra_id_9> of 0.1 K. <extra_id_10> 30-130 solar flux units. At the solar surface the estimated rapid brightenings were of 50-150 K Comments: 12 pages including 6 <extra_id_11> Physics, April 2010
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<extra_id_0> During <extra_id_1> M. <extra_id_2> Rogerio Marcon, <extra_id_3> Adolfo Marun, Rodolfo <extra_id_4> Abstract: Solar observations <extra_id_5> 8-14 \mu\m band continuum were <extra_id_6> on <extra_id_7> with 10.5 <extra_id_8> Minimum detectable temperature <extra_id_9> change was <extra_id_10> The corresponding fluxes are <extra_id_11> figures. Accepted by Solar <extra_id_12>
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Title: Evidence for Gamma-Ray Halos Around Active Galactic Nuclei and the First Measurement of Intergalactic Magnetic FieldsCategory: astro-ph.HE astro-ph.CO hep-phAuthors: Shin'ichiro <extra_id_0> Alexander Kusenko (UCLA/Tokyo)Study Abstract: Intergalactic magnetic fields (IGMF) can <extra_id_1> the appearance of halos around the gamma-ray images of distant objects because an electromagnetic cascade initiated by a high-energy gamma-ray interaction with the photon background is broadened by magnetic deflections. We report evidence of such gamma-ray halos in the stacked images of the 170 brightest active galactic nuclei (AGN) in the 11-month source <extra_id_2> Fermi Gamma-Ray Space Telescope. Excess over point spread function in the surface brightness profile is statistically significant at 3.5\sigma (99.95% confidence <extra_id_3> for the nearby, hard population of AGN. The halo size and brightness are consistent with IGMF, B_{IGMF} ~ 10^{-15} G. The knowledge of IGMF <extra_id_4> facilitate the future gamma-ray and <extra_id_5> since IGMF are likely to originate from the primordial seed fields created shortly after the Big Bang, this potentially opens a new window on the origin of cosmological <extra_id_6> the phase transitions in the early Universe. Comments: 14 pages, 4 figures; detailed discussion on instrumental effects; conclusions unchanged; accepted to ApJ Letters
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<extra_id_0> Ando (Caltech), <extra_id_1> cause <extra_id_2> catalog of the <extra_id_3> level), <extra_id_4> will <extra_id_5> charged-particle astronomy. Furthermore, <extra_id_6> magnetic fields, inflation, and <extra_id_7>
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Title: <extra_id_0> Using Improper Frame PaddingCategory: cs.CRAuthors: Bartosz Jankowski, Wojciech Mazurczyk, Krzysztof SzczypiorskiStudy <extra_id_1> information in network traffic may lead to leakage of confidential information. In this paper we introduce a new steganographic system: the PadSteg (Padding Steganography). To authors' best knowledge it is the first information hiding solution which represents interprotocol steganography i.e. usage of <extra_id_2> or more protocols from the TCP/IP stack to enable secret communication. PadSteg utilizes ARP and TCP protocols together with an Etherleak vulnerability (improper Ethernet frame padding) to facilitate secret communication for hidden groups in LANs (Local Area Networks). Basing on real network traces we confirm that PadSteg is feasible in today's networks and we estimate what steganographic bandwidth is achievable while limiting the chance of disclosure. We also point at possible countermeasures against PadSteg. Comments: 6 pages, 8 figures
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<extra_id_0> Information Hiding <extra_id_1> Abstract: Hiding <extra_id_2> relation between two <extra_id_3>
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Title: Polarization as <extra_id_0> indicator of intrinsic alignment in radio weak lensingCategory: astro-ph.COAuthors: Michael L. Brown and Richard A. BattyeStudy Abstract: We propose a new technique for weak gravitational lensing in the radio band making use of polarization information. Since the orientation of a galaxy's polarized emission is both unaffected by lensing and is related to the galaxy's intrinsic orientation, it effectively provides information on the unlensed galaxy <extra_id_1> a new weak <extra_id_2> estimator which exploits this effect and makes full use of both the observed galaxy shapes and the estimates of the intrinsic position angles as provided by polarization. Our method has the potential to both reduce the effects of shot noise, and to reduce to negligible levels, in a model-independent way, all effects of intrinsic galaxy alignments. We test our technique on simulated weak lensing skies, including an intrinsic alignment contaminant consistent with recent observations, in three overlapping redshift bins. Adopting a standard weak lensing analysis and ignoring intrinsic alignments results in biases of 5-10% in <extra_id_3> <extra_id_4> cosmological parameters. Applying our new estimator to one tenth the number of galaxies used for the standard case, we recover both power spectra and <extra_id_5> with similar <extra_id_6> to the standard case and with negligible residual bias, <extra_id_7> the presence of a substantial (astrophysical) scatter in the relationship between the observed orientation of the polarized emission and the intrinsic orientation. Assuming a reasonable polarization fraction for star-forming galaxies, and no cosmological conspiracy in the relationship between polarization direction and intrinsic morphology, our estimator should <extra_id_8> valuable <extra_id_9> for weak lensing analyses of forthcoming radio surveys, in particular, deep wide <extra_id_10> e-MERLIN, <extra_id_11> ASKAP and ultimately, definitive radio lensing surveys with the SKA. Comments: 18 pages, 10 figures, submitted to MNRAS
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<extra_id_0> an <extra_id_1> position angle. We derive <extra_id_2> lensing <extra_id_3> the recovered <extra_id_4> power spectra and <extra_id_5> the input cosmology <extra_id_6> precision as compared <extra_id_7> even in <extra_id_8> prove a <extra_id_9> tool <extra_id_10> field surveys with <extra_id_11> MeerKAT and <extra_id_12>
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Title: Revisiting fifth forces <extra_id_0> modelCategory: astro-ph.CO hep-ph <extra_id_1> Clare Burrage and David SeeryStudy Abstract: A Galileon field is one which obeys a spacetime generalization of the non-relativistic Galilean invariance. Such a field may possess non-canonical kinetic terms, but ghost-free theories with a well-defined Cauchy problem exist, constructed using a finite number of <extra_id_2> of this scalar with matter <extra_id_3> <extra_id_4> the Galileon to become weakly coupled near heavy <extra_id_5> of the fifth force mediated by a Galileon field, and show that the parameters of the model are less constrained by experiment than previously supposed. Comments: 14 pages
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<extra_id_0> in the Galileon <extra_id_1> hep-thAuthors: <extra_id_2> relevant operators. The interactions <extra_id_3> are hidden <extra_id_4> by the Vainshtein effect, causing <extra_id_5> sources. We revisit estimates <extra_id_6>
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Title: Phase transitions <extra_id_0> cond-mat.quant-gas cond-mat.soft cond-mat.stat-mechAuthors: Daniel G. Barci and Eduardo FradkinStudy Abstract: We study properties of phase transitions of 2D superconductor liquid crystal phases, and analyze the competition between the recently proposed Pair Density Wave (PDW) and nematic $4e$ superconductor ($4e$SC). Nematic fluctuations enhance the $4e$SC and suppress the PDW phase. In the absence of lattice effects, the PDW state exists only <extra_id_1> and the low temperature phase is a nematic $4e$SC with short ranged PDW order. A geometric description of the $4e$ SC is presented. Comments: 4 pages, 3 figures. Edited file with a new discussion on quasiparticle behavior in the charge 4e <extra_id_2> appear in Physical Review B Rapid Communications
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<extra_id_0> in superconductor liquid crystalsCategory: cond-mat.supr-con <extra_id_1> at T=0 <extra_id_2> nematic superconductor. To <extra_id_3>
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Title: Fast Pixel Space Convolution for CMB Surveys with Asymmetric Beams and Complex Scan Strategies: FEBeCoPCategory: astro-ph.CO gr-qcAuthors: S. Mitra, G. Rocha, K. <extra_id_0> G\'orski, <extra_id_1> M. Huffenberger, H. K. Eriksen, M. A. J. Ashdown and C. R. LawrenceStudy Abstract: Precise measurement of the angular power spectrum of the Cosmic Microwave Background (CMB) temperature and polarization anisotropy can tightly constrain many cosmological models <extra_id_2> accurate measurements can only be realized in practice provided all major systematic effects have been taken into account. Beam <extra_id_3> with the scan strategy, is a major source of systematic error in scanning CMB experiments such as Planck, the focus of our current interest. We envision Monte Carlo methods to rigorously <extra_id_4> account for the systematic effect of beams in CMB analysis. Toward that goal, we <extra_id_5> <extra_id_6> convolution method that can simulate sky maps <extra_id_7> scanning instrument, taking into account real beam shapes and scan strategy. The essence is to pre-compute the "effective beams" using a computer code, "Fast Effective Beam Convolution in <extra_id_8> we have <extra_id_9> for the Planck mission. The code computes effective beams given the focal plane beam characteristics of the Planck instrument and the full history of actual satellite pointing, and performs very fast convolution of <extra_id_10> using the effective beams. <extra_id_11> paper, we describe the algorithm and the computational scheme that <extra_id_12> We also outline a few <extra_id_13> effective beams in the precision analysis of Planck data, for characterizing the CMB anisotropy and for detecting and measuring properties of point sources. Comments: 26 pages, <extra_id_14> subsection on beam/PSF statistics, new and better figures, more explicit algebra for polarized beams, added explanatory text at many places following referees comments [Accepted for publication in ApJS]
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<extra_id_0> M. <extra_id_1> K. <extra_id_2> and parameters. However, <extra_id_3> asymmetry, coupled <extra_id_4> study and <extra_id_5> have developed a fast <extra_id_6> pixel space <extra_id_7> observed by a <extra_id_8> Pixel space" (FEBeCoP), that <extra_id_9> developed <extra_id_10> sky signals <extra_id_11> In this <extra_id_12> has been implemented. <extra_id_13> applications of the <extra_id_14> 15 figures. New <extra_id_15>
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Title: On the Existence of Energy-Preserving Symplectic Integrators Based upon Gauss Collocation FormulaeCategory: math.NAAuthors: Luigi Brugnano, Felice Iavernaro, Donato TrigianteStudy Abstract: We introduce a new family of symplectic integrators depending on a real parameter. When the paramer is zero, the corresponding method in the family becomes the classical Gauss collocation formula of order 2s, where s denotes the number of the internal stages. For any given non-null value of <extra_id_0> corresponding method remains symplectic and has order 2s-2: hence it may be interpreted as an order 2s-2 (symplectic) perturbation of the Gauss method. Under suitable assumptions, we show that the <extra_id_1> be properly tuned, at <extra_id_2> the integration procedure, <extra_id_3> to guarantee energy conservation in the numerical solution. The resulting symplectic, energy conserving method shares the same order 2s as the generating Gauss formula. Comments: 19 pages, 7 figures; Sections 1, 2, and 6 sliglthly modified
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<extra_id_0> the parameter, the <extra_id_1> free parameter may <extra_id_2> each step of <extra_id_3> so as <extra_id_4>
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Title: Testing the No-Hair Theorem with Observations in the Electromagnetic Spectrum: II. Black-Hole ImagesCategory: astro-ph.HE gr-qcAuthors: Tim Johannsen (Arizona), Dimitrios Psaltis (Arizona)Study Abstract: According to the no-hair theorem, all astrophysical black holes <extra_id_0> by their masses and spins. This theorem can be tested observationally by measuring (at least) three different multipole moments of the spacetimes of black <extra_id_1> paper, we analyze images of black holes within a framework that allows us to calculate observables in the electromagnetic spectrum as a function of the mass, spin, and, independently, the quadrupole moment of a black hole. We show that a deviation of the quadrupole moment from the expected Kerr value leads to images of black holes that are either prolate or oblate depending on the sign and magnitude of <extra_id_2> there is a ring-like structure around the black-hole shadow with a diameter of <extra_id_3> masses that is substantially brighter than the image of the underlying accretion flow and that is independent of the astrophysical details <extra_id_4> We show that the shape of this ring depends directly on the mass, spin, and quadrupole moment of the black hole and can be used for an independent measurement of all three parameters. In particular, we demonstrate that this ring is highly circular for a Kerr black hole with a spin a<0.9M, independent of the <extra_id_5> becomes elliptical and asymmetric <extra_id_6> theorem is <extra_id_7> baseline interferometric observations of Sgr A* will image this ring and may allow for an observational test of the no-hair theorem. Comments: Accepted for publication in ApJ
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<extra_id_0> are fully described <extra_id_1> holes. In this <extra_id_2> the deviation. In addition, <extra_id_3> about 10 black-hole <extra_id_4> of accretion flow models. <extra_id_5> observer's inclination, but <extra_id_6> if the no-hair <extra_id_7> violated. Near-future very-long <extra_id_8>
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Title: Radio and X-ray Observations of the Type Ic SN 2007gr Reveal an Ordinary, Non-relativistic ExplosionCategory: astro-ph.COAuthors: Alicia M. Soderberg, Andreas Brunthaler, Ehud Nakar, Roger A. Chevalier, Michael F. BietenholzStudy Abstract: We present extensive radio and X-ray observations of the nearby Type Ic SN 2007gr in NGC 1058 obtained <extra_id_0> the Very Large Array and <extra_id_1> X-ray Observatory and spanning 5 to 150 days <extra_id_2> Through our detailed modeling of <extra_id_3> estimate the properties of the blastwave and the circumstellar environment. We find <extra_id_4> for a freely-expanding and non-relativistic explosion with an average blastwave velocity, v~0.2c, and a total internal energy for <extra_id_5> <extra_id_6> emitting material of E ~ 2 x 10^46 erg assuming equipartition of energy between <extra_id_7> magnetic fields (epsilon_e=epsilon_B=0.1). The temporal <extra_id_8> of the radio emission points to <extra_id_9> stellar wind-blown environment shaped by a steady progenitor mass loss rate of Mdot ~ 6 x 10^-7 solar <extra_id_10> year <extra_id_11> <extra_id_12> are fully consistent with those inferred for <extra_id_13> and are in line with the expectations for an ordinary, homologous SN explosion. Our results are at odds with those <extra_id_14> (2010) <extra_id_15> evidence for a relativistic blastwave in SN 2007gr based on <extra_id_16> the radio emission was resolved away in <extra_id_17> low signal-to-noise Very Long Baseline Interferometry (VLBI) observation. Here <extra_id_18> show that the exotic physical scenarios required to explain the claimed relativistic velocity -- extreme departures from equipartition and/or a highly collimated outflow -- are excluded by our detailed Very Large Array radio observations. Moreover, we present an independent analysis of the VLBI data and propose that a modest loss of phase <extra_id_19> a more natural explanation for the apparent flux density loss which is <extra_id_20> on both short and long baselines. We conclude that SN 2007gr is an <extra_id_21> Ibc supernova. Comments: 14 pages, 6 figures, submitted to ApJ
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<extra_id_0> with <extra_id_1> the Chandra <extra_id_2> after explosion. <extra_id_3> these data, we <extra_id_4> evidence <extra_id_5> the <extra_id_6> radio <extra_id_7> electrons and <extra_id_8> and spectral evolution <extra_id_9> a <extra_id_10> masses per <extra_id_11> (wind velocity, v_w=10^3 km/s). <extra_id_12> These parameters <extra_id_13> other SNe Ibc <extra_id_14> of Paragi et al. <extra_id_15> who recently reported <extra_id_16> their claim that <extra_id_17> a <extra_id_18> we <extra_id_19> coherence provides <extra_id_20> evident <extra_id_21> ordinary Type <extra_id_22>
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