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April 2006 arXiv papers — page 7

Showing 601700 of 3,886 papers

  1. Aiichi Iwazaki

    We apply the effective theory of color glass condensate to the analysis of gluon states in dense quark matter, in which the saturation region of gluons is also present. We find that in the region two point function of gluons shows algebraic long range order. The order is completely the same as the one gluons show in the dense quark matter, which form quantum

  2. A. Bhattacharya, S. N. Banerjee, B. Chakraborti, S. Banerjee

    The properties of the proton has been investigated considering a proton as diquark-quark system. A model for diquark has been suggested in an analogy with the quasi-particle in a crystal lattice. The mass of the diquark obtained in the present model has been found to be in good agreement with other theoretical predictions. The binding energy of proton, compr

  3. Jason Doukas, S. Rai Choudhury, G. C. Joshi

    Black holes at the TeV scale are investigated in the extra large dimension scenario. We interpret the lightest black hole excitation as a singlet scalar field, and show how interaction terms can be appended to the standard model at the dimension five non-renormalizable level. Lepton family number violation is natural in this model. Muon magnetic moment, and

  4. KLOE Collaboration

    We describe the method of measuring the integrated luminosity of the $e^+e^-$ collider DA$Φ$NE, the Frascati $ϕ-$factory. The measurement is done with the KLOE detector selecting large angle Bhabha scattering events and normalizing them to the effective cross section. The $e^+e^- \to e^+e^-(γ)$ cross section is calculated using different event generators whi

  5. Clas Collaboration, S. Niccolai

    For the first time, the reaction gamma d -> Lambda n K+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Lab, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the

  6. M. Demetrian, P. Presnajder

    We present a new point of view on the problem of the Schwarzschild black hole in the noncommutative spaces, proposed recently by F. Nasseri. We apply our treatment also to the case of the 2+1 dimensional Ba\~ nados-Teitelboim-Zanelli black hole.

  7. Fangyu Li, R. M. L. Baker,, Zhenya Chen

    There exist corresponding metric perturbations of the relic gravitational waves (GWs) in the region of approximately h~10^(-30)-10^(-32)in the GHz band. A detector for these GWs is described in which we measure the perturbative photon flux (PPF) or signal generated by such high-frequency relic GWs (HFRGWs) via a coupling system of fractal membranes and a Gau

  8. Ofer Shayevitz, Ram Zamir, Meir Feder

    We address the problem of delay in an arithmetic coding system. Due to the nature of the arithmetic coding process, source sequences causing arbitrarily large encoding or decoding delays exist. This phenomena raises the question of just how large is the expected input to output delay in these systems, i.e., once a source sequence has been encoded, what is th

  9. Farid Benbadis, Jean-Jacques Puig, Marcelo Dias de Amorim, Claude Chaudet

    Positioning systems in self-organizing networks generally rely on measurements such as delay and received signal strength, which may be difficult to obtain and often require dedicated equipment. An alternative to such approaches is to use simple connectivity information, that is, the presence or absence of a link between any pair of nodes, and to extend it t

  10. Akiko Manada, Navin Kashyap

    A construction of Crochemore, Mignosi and Restivo in the automata theory literature gives a presentation of a finite-type constrained system (FTCS) that is deterministic and has a relatively small number of states. This construction is thus a good starting point for determining the minimal deterministic presentation, known as the Shannon cover, of an FTCS. W

  11. Y. Guan, W. E. Bailey, E. Vescovo, C. -C. Kao

    We present a time-resolved measurement of magnetization dynamics during ferromagnetic resonance (FMR) in a single layer of Ni81Fe19. Small-angle (<1 deg.) precession of elemental Ni, Fe moments could be measured directly and quantitatively using time-resolved x-ray magnetic circular dichroism (XMCD) in transmission. The high temporal and rotational sensitivi

  12. E. Onac, F. Balestro, L. H. Willems van Beveren, U. Hartmann

    We present the experimental realization of a Quantum Dot (QD) operating as a high-frequency noise detector. Current fluctuations produced in a nearby Quantum Point Contact (QPC) ionize the QD and induce transport through excited states. The resulting transient current through the QD represents our detector signal. We investigate its dependence on the QPC tra

  13. A. D. Bortolozo, O. H. SantAnna, M. S. da Luz, C. A. M. dos Santos

    Nb2SnC is a member of the large family of lamellar materials that crystallize in the hexagonal structure with space group P63/mmc which are isomorphs with Cr2AlC, also named H-phase. In spite of the great number of compounds which belong to this family, the superconductivity has been reported only for two cases: Mo2GaC and Nb2SC. In this work we show that su

  14. Jason Alicea, Matthew P. A. Fisher

    Starting from the graphene lattice tight-binding Hamiltonian with an on-site U and long-range Coulomb repulsion, we derive an interacting continuum Dirac theory governing the low-energy behavior of graphene in an applied magnetic field. Initially, we consider a clean graphene system within this effective theory and explore integer quantum Hall ferromagnetism

  15. R. N. Palmer, D. Jaksch

    We consider interacting bosonic atoms in an optical lattice subject to a large simulated magnetic field. We develop a model similar to a bilayer fractional quantum Hall system valid near simple rational numbers of magnetic flux quanta per lattice cell. Then we calculate its ground state, magnetic lengths, fractional fillings, and find unexpected sign changes

  16. Y. Alhassid

    We discuss mesoscopic effects in quantum dots, nanoparticles and nuclei. In quantum dots, we focus on the statistical regime of dots whose single-electron dynamics are chaotic. Random matrix theory methods, developed to explain the statistics of neutron resonances in compound nuclei, are useful in describing the mesoscopic fluctuations of the conductance in

  17. Mauro M. Doria, S. Salem-Sugui, P. Badica, K. Togano

    The scaling approach recently proposed by Landau and Ott for isothermal magnetization curves is extended to the average kinetic energy density of the condensate. Two low $T_c$ superconductors, Nb and $Li_{2}Pd_{3}B$ are studied and their isothermal reversible magnetization shown to display Landau and Ott scaling. Good agreement is obtained for the upper crit

  18. Catalin Gainaru, Alexander Brodin, Vladimir Novikov, Ernst A. Rössler

    The temperature evolution of the broadband $10^{-6}$-$10^{10}$ Hz dielectric susceptibility of the paradigmatic glass formers glycerol, propylene carbonate, and fluoro-aniline is analyzed assuming a three-step relaxation due to the $α$-process, its excess wing, and a $β$-process. We find that the $α$-peak and the wing can be described by susceptibility funct

  19. Gabriel Bester, Xifan Wu, David Vanderbilt, Alex Zunger

    We show that the piezoelectric effect that describes the emergence of an electric field in response to a crystal deformation in III-V semiconductors such as GaAs and InAs has strong contributions from second-order effects that have been neglected so far. We calculate the second-order piezoelectric tensors using density functional theory and obtain the piezoe

  20. Otto L. Muskens, Maarten H. M. van Weert, Magnus T. Borgstrom, Erik P. A. M. Bakkers

    Semiconductor nanowires exhibit large polarization anisotropy for the absorption and emission of light, making them ideal building blocks for novel photonic metamaterials. Here, we demonstrate that a high density of aligned nanowires exhibits giant optical birefringence, a collective phenomenon observable uniquely for collections of wires. The nanowire mater

  21. Shu-Chiuan Chang, Wenya Wang

    For a lattice $Λ$ with $n$ vertices and dimension $d$ equal or higher than two, the number of spanning trees $N_{ST}(Λ)$ grows asymptotically as $\exp(n z_Λ)$ in the thermodynamic limit. We present exact integral expressions for the asymptotic growth constant $z_Λ$ for spanning trees on several lattices. By taking different unit cells in the calculation, man

  22. S. A. Jafari, T. Tohyama, S. Maekawa

    We formulate the third harmonic generation (THG) within the dynamical mean field theory (DMFT) approximation of the Hubbard model. In the limit of large dimensions, where DMFT becomes exact, the vertex corrections to current vertices are identically zero, and hence the calculation of the THG spectrum reduces to a time-ordered convolution, followd by appropri

  23. V. P. S. Awana, Rajeev Ranjan, Rajeev Rawat, L. S. Sharath Chandra

    This is the first report of the observation of the onset of excess volume and also of the strain along the a-axis near the magnetic ordering temperature in Ru-1222 superconductor, and indicates a coupling between the lattice and the magnetism in this system. Magnetization, magneto transport and thermoelectric power measurements being carried out on the same

  24. V. P. S. Awana, S. Balamurugan, Akshay Deshpande, L. S. Sharath Chandra

    We carefully studied the nonsuperconducting sample of the magneto-superconducting RuSr2(Eu1-xCex)Cu2O10 series with composition RuSr2EuCeCu2O10. This compound seems to exhibit a complex magnetic state as revealed by host of techniques like resistivity, thermopower, magnetic susceptibility and MR measurements.

  25. S S Rao, S V Bhat

    Nanoparticles (dia ~ 5 - 7 nm) of Bi_0.5 X_0.5(X=Ca,Sr)MnO_3 are prepared by polymer assisted sol-gel method and characterized by various physico-chemical techniques. X-ray diffraction gives evidence for single phasic nature of the materials as well as their structures. Mono dispersed to a large extent, isolated nanoparticles are seen in the transmission ele

  26. J. E. Han

    By mapping steady-state nonequilibrium to an effective equilibrium, we formulate nonequilibrium problems within an equilibrium picture where we can apply existing equilibrium many-body techniques to steady-state electron transport problems. We study the analytic properties of many-body scattering states, reduce the boundary condition operator in a simple for

  27. Mathias Koerner, Helmut G. Katzgraber, Alexander K. Hartmann

    We propose a simple and general procedure based on a recently introduced approach that uses an importance-sampling Monte Carlo algorithm in the disorder to probe to high precision the tails of ground-state energy distributions of disordered systems. Our approach requires an estimate of the ground-state energy distribution as a guiding function which can be o

  28. B. Trauzettel, A. N. Jordan, C. W. J. Beenakker, M. Buttiker

    We propose a realization of a charge parity meter based on two double quantum dots alongside a quantum point contact. Such a device is a specific example of the general class of mesoscopic quadratic quantum measurement detectors previously investigated by Mao et al. [Phys. Rev. Lett. 93, 056803 (2004)]. Our setup accomplishes entangled state preparation by a

  29. Kenji Kamide, Yuji Tsukada, Susumu Kurihara

    We investigate spin-charge mixing effect on resonant tunneling in spin-polarized Tomonaga-Luttinger liquid with double impurities. The mixing arises from Fermi velocity difference between two spin species due to Zeeman effect. Zero bias conductance is calculated as a function of gate voltage $V_{\rm g}$, gate magnetic field $B_{\rm g}$, temperature and magne

  30. Jinwu Ye

    This paper was withdrawn and incorporated into section II of cond-mat/0310512

  31. V. A Marsakov, T. V. Borkova

    We analyze the relations between the relative magnesium abundances in stars and their metallicities, Galactic orbital elements, and ages. The relative magnesium abundances in metal-poor ([Fe/H] < -0.4) thin-disk stars have been found to systematically decrease with increasing stellar orbital radii in such a way that magnesium over abundances ([Mg/Fe]>0.2 dex

  32. Scott S. Sheppard, David C. Jewitt, Jan Kleyna

    We surveyed 1.75 square degrees of sky near Neptune to an R-band 50% detection efficiency of 25.8 mags (corresponding to radii of about 17 km for an assumed albedo of 0.04). We discovered one new outer satellite, Psamathe (S/2003 N1), about 20 km in radius and having a distant retrograde orbit and moderate eccentricity. Until 2003 Neptune was only known to h

  33. Christopher D. Sheehy, Nate McCrady, James R. Graham

    The point-spread function (PSF) of an adaptive optics (AO) system is often poorly known. This ignorance can lead to significant systematic errors in photometry. Since the degree of AO correction is sensitive to the observing conditions: seeing, wind speed, brightness of the wavefront reference, etc., it would be desirable to estimate the PSF from the data th

  34. S. Kozlowski, P. R. Wozniak, S. Mao, M. C. Smith

    We present a proper motion mini-survey of 35 fields in the vicinity of Baade window, (l, b) = (1 deg, -4 deg), sampling roughly a 5 x 2.5 deg region of the Galactic bar. Our second epoch observations collected with the ACS/HRC instrument on board the Hubble Space Telescope were combined with the archival WFPC2/PC images. The resulting time baselines are in t

  35. Jesper Rasmussen, Trevor J. Ponman, John S. Mulchaey

    Ram pressure stripping of galactic gas is generally assumed to be inefficient in galaxy groups due to the relatively low density of the intragroup medium and the small velocity dispersions of groups. To test this assumption, we obtained Chandra X-ray data of the starbursting spiral NGC 2276 in the NGC 2300 group of galaxies, a candidate for a strong galaxy i

  36. David B. Cline, Fabrizio Raffaelli, Franco Sergiampietri

    A scalable line of liquid argon TPC detectors is described, based on a three dimensional cubic frame array immersed on a common liquid argon volume. The paper describes general lines, main construction criteria, crucial points, parameters and required preliminary R&D activities for the construction of detectors with active mass ranging from 200 ton to 100 kT

  37. T. Ryabchikova, A. Ryabtsev, O. Kochukhov, S. Bagnulo

    We have obtained a UVES spectrum of a slowly rotating strongly magnetic Ap star, HD 144897, that exhibits very large overabundances of rare-earth elements. Here we present a detailed spectral analysis of this object, also taking into account effects of non-uniform vertical distribution (stratification) of chemical elements. We have determined the photospheri

  38. Akira Mizuta, Jave O. Kane, Marc W. Pound, Bruce A. Remington

    We investigate numerically the hydrodynamic instability of an ionization front (IF) accelerating into a molecular cloud, with imposed initial perturbations of different amplitudes. When the initial amplitude is small, the imposed perturbation is completely stabilized and does not grow. When the initial perturbation amplitude is large enough, roughly the rati

  39. Christine C. Dantas, Fernando M. Ramos

    In this paper we present a study of the cosmic flow from the point of view of how clusterings at different dynamical regimes in an expanding universe evolve according to a `coarse-grained&#39; partitioning of their ranked energy distribution. By analysing a Lambda-CDM cosmological simulation from the Virgo Project, we find that cosmic flows evolve in an orde

  40. I. Agudo, J. L. Gomez, D. C. Gabuzda, A. P. Marscher

    We present polarimetric 5 GHz to 43 GHz VLBI observations of the BL Lacertae object PKS 0735+178, spanning March 1996 to May 2000. Comparison with previous and later observations suggests that the overall kinematic and structural properties of the jet are greatly influenced by its activity. Time intervals of enhanced activity, as reported before 1993 and aft

  41. R. Tuellmann, D. Breitschwerdt, J. Rossa, W. Pietsch

    In Paper I we showed that multi-phase gaseous halos of late-type spiral galaxies, detected in the radio continuum, in Halpha, and in X-rays, are remarkably well correlated regarding their morphology and spatial extent. In this work we present new results from a statistical analysis in order to specify and quantify these phenomenological relations. This is ac

  42. Jay Anderson, Luigi R. Bedin, Giampaolo Piotto, Ramakant Singh Yadav

    This paper is the first of a series of papers in which we will apply the methods we have developed for high-precision astrometry (and photometry) with the Hubble Space Telescope to the case of wide-field ground-based images. In particular, we adapt the software originally developed for WFPC2 to ground-based, wide field images from the WFI at the ESO 2.2m tel

  43. P. Beirao, B. R. Brandl, D. Devost, J. D. Smith

    We present new Spitzer Space Telescope data on the nearby, low-metallicity starburst galaxy NGC 5253, from the Infrared Array Camera IRAC and the Infrared Spectrograph IRS. The mid-IR luminosity profile of NGC 5253 is clearly dominated by an unresolved cluster near the center, which outshines the rest of the galaxy at longer wavelengths. We find that the [Ne

  44. J. Einasto, M. Einasto, E. Saar, E. Tago

    We investigate properties of superclusters of galaxies found on the basis of the 2dF Galaxy Redshift Survey, and compare them with properties of superclusters from the Millennium Simulation. We study the dependence of various characteristics of superclusters on their distance from the observer, on their total luminosity, and on their multiplicity. The multip

  45. S. L. Kenyon, J. S. Lawrence, M. C. B. Ashley, J. W. V. Storey

    We present low-resolution turbulence profiles of the atmosphere above Dome C, Antarctica, measured with the MASS instrument during 25 nights in March-May 2004. Except for the lowest layer, Dome C has significantly less turbulence than Cerro Tololo and Cerro Pachon. In particular, the integrated turbulence at 16 km is always less than the median values at the

  46. Biping Gong

    Superluminal motion has been interpreted as relativistically moving out flow. The increasing observations of such sources provide chance to investigate their mechanism in detail. This paper proposes that superluminal motion may be jet precession induced blob motion. This model can interpret a number of observational phenomena which are not well understood un

  47. Chang Hyun Baek, Dongsu Ryu, Hyesung Kang, Jongsoo Kim

    Thermal-gravitational instability (TGI) is studied in the protogalactic environment. We extend our previous work, where we found that dense clumps first form out of hot background gas by thermal instability and later a small fraction of them grow to virialized clouds of mass M_c >~ 6X10^6 M_sun by gravitational infall and merging. But these clouds have large

  48. Mark A. Fardal, Neal Katz, David H. Weinberg, Romeel Dav&#39;e

    The total extragalactic background radiation can be an important test of the global star formation history (SFH). Using direct observational estimates of the SFH, along with standard assumptions about the initial mass function (IMF), we calculate the total extragalactic background radiation and the observed stellar density today. We show that plausible SFHs

  49. Connie Te-ching Chang, James P. Sethna

    We provide a theory for the effects of polarons and phonons in mediating and suppressing the quantum tunneling of electrons into single molecules of conducting polymers, motivated by experiments on molecular quantum dots. The effects of both phonons and excitations of the polaron particle-in-a-box excitations are calculated. Using both the Su-Schrieffer-Heeg

  50. Dorin E. Dutkay, Palle E. T. Jorgensen

    We examine two questions regarding Fourier frequencies for a class of iterated function systems (IFS). These are iteration limits arising from a fixed finite families of affine and contractive mappings in $\br^d$, and the ``IFS&#39;&#39; refers to such a finite system of transformations, or functions. The iteration limits are pairs $(X, μ)$ where $X$ is a co

  51. Yongquan Xue, Feng Yuan, Wei Cui

    The spectral energy distribution (SED) of TeV blazars peaks both at keV and TeV energies. The X-ray emission is generally believed to originate in the synchrotron emission from relativistic electrons (and positrons) in the jet of these sources, while the origin of the gamma-ray emission is still being debated. We report results from a systematic study of X-r

  52. A. Sergyeyev

    In this brief note we present a zero-curvature representation for one of the new integrable system found by Mikhailov, Novikov and Wang in nlin.SI/0601046.

  53. Lianyi He, Meng Jin, Pengfei Zhuang

    We investigate the superfluidity and the associated Nambu-Goldstone modes in a three-flavor atomic Fermi gas with SU(3) global symmetry. The s-wave pairing occurs in flavor anti-triplet channel due to the Pauli principle, and the superfluid state contains both gapped and gapless fermionic excitations. Corresponding to the spontaneous breaking of the SU(3) sy

  54. W. M. Witzel, S. Das Sarma

    We describe how the spin coherence time of a localized electron spin in solids, i.e. a solid state spin qubit, can be prolonged by applying designed electron spin resonance pulse sequences. In particular, the spin echo decay due to the spectral diffusion of the electron spin resonance frequency induced by the non-Markovian temporal fluctuations of the nuclea

  55. T. P. Mayer Alegre, F. G. G. Hernández, A. L. C. Pereira, G. Medeiros-Ribeiro

    Understanding the electronic structure of semiconductor nanostructures is not complete without a detailed description of their corresponding spin-related properties. Here we explore the response of the shell structure of InAs self-assembled quantum dots to magnetic fields oriented in several directions, allowing the mapping of the g-tensor modulus for the s

  56. E. R. Siegel, J. N. Fry

    This paper examines the generation of seed magnetic fields due to the growth of cosmological perturbations. In the radiation era, different rates of scattering from photons induce local differences in the ion and electron density and velocity fields. The currents due to the relative motion of these fluids generate magnetic fields on all cosmological scales,

  57. Fernando Kokubun, Vilson T. Zanchin

    The emission of electromagnetic waves from a system described by the Hénon-Heiles potential is studied in this work. The main aim being to analyze the behavior of the system when the damping term is included explicitly into the equations of motion. Energy losses at the chaotic regime and at the regular regime are compared. The results obtained here are simil

  58. Nissan Itzhaki

    We propose a model of dynamical relaxation of the cosmological constant. Technical naturalness of the model and the present value of the vacuum energy density imply an upper bound on the supersymmetry breaking scale and the reheating temperature at the TeV scale.

  59. Robin Houston

    If a compact closed category has finite products or finite coproducts then it in fact has finite biproducts, and so is semi-additive.

  60. Ilia Gogoladze, Tianjun Li, V. N. Senoguz, Qaisar Shafi

    We consider orbifold GUTs with N=1 supersymmetry in which the Standard Model (SM) gauge couplings are unified at M_GUT =~ 2 x 10^16 GeV with one of the third family (charged) Yukawa couplings. With split supersymmetry the SM Higgs mass is estimated to be 131 +/- 10 GeV for gauge-top quark Yukawa unification, which increases to 146 +/- 8 GeV for gauge-bottom

  61. Abhishek Parakh

    This paper presents protocols for Kak&#39;s cubic transformation and proposes a modification to Diffie-Hellman key exchange protocol in order to achieve asymmetric oblivious exchange of keys.

  62. Cecilia Scannapieco, Patricia B. Tissera, Simon D. M. White, Volker Springel

    We have developed a new scheme to treat a multiphase interstellar medium in smoothed particle hydrodynamics simulations of galaxy formation. This scheme can represent a co-spatial mixture of cold and hot ISM components, and is formulated without scale-dependent parameters. It is thus particularly suited to studies of cosmological structure formation where ga

  63. Santo Fortunato, Alessandro Flammini

    PageRank, the prestige measure for Web pages used by Google, is the stationary probability of a peculiar random walk on directed graphs, which interpolates between a pure random walk and a process where all nodes have the same probability of being visited. We give some exact results on the distribution of PageRank in the cases in which the damping factor q a

  64. P. A. Varotsos, N. V. Sarlis, E. S. Skordas, H. K. Tanaka

    As mentioned in the preceding additional information (hereafter called Part I), a series of strong earthquakes with magnitudes between 5.2 and 5.9-units occurred during the two weeks period: 3 to 19 April, 2006 with epicenters lying at distances 80 to 100 km west of PAT station. Here, we show that the analysis in the natural time of the seismicity that occur

  65. Joeri Van der Veken

    We give a full classification of higher order parallel surfaces in three-dimensional homogeneous spaces with four-dimensional isometry group, i.e. in the so-called Bianchi-Cartan-Vranceanu family. This gives a positive answer to a conjecture formulated in 2002. As a partial result, we prove that totally umbilical surfaces only exist if the space is a Riemann

  66. C. M. Hull

    The gauged sigma-model argument that string backgrounds related by T-dual give equivalent quantum theories is revisited, taking careful account of global considerations. The topological obstructions to gauging sigma-models give rise to obstructions to T-duality, but these are milder than those for gauging: it is possible to T-dualise a large class of sigma-m

  67. Meng-Chwan Tan

    In this paper, we study the perturbative aspects of a twisted version of the two-dimensional $(0,2)$ heterotic sigma model on a holomorphic gauge bundle $\mathcal E$ over a complex, hermitian manifold $X$. We show that the model can be naturally described in terms of the mathematical theory of ``Chiral Differential Operators&#34;. In particular, the physical

  68. Jose J. Blanco-Pillado, Michele Redi

    We study the dynamics of BPS string-like objects obtained by lifting monopole and dyon solutions of N=2 Super-Yang-Mills theory to five dimensions. We present exact traveling wave solutions which preserve half of the supersymmetries. Upon compactification this leads to macroscopic BPS rings in four dimensions in field theory. Due to the fact that the strings

  69. Bernhard Hanke, Thomas Schick

    In a previous paper, we showed nonvaninishing of the universal index elements in the K-theory of the maximal C*-algebras of the fundamental groups of enlargeable spin manifolds. The underlying notion of enlargeability was the one from the first relevant paper of Gromov and Lawson, involving contracting maps defined on finite covers of the given manifolds. In

  70. R. A. Osten, R. Jayawardhana

    We report on searches for radio emission from three of the nearest known young brown dwarfs using the Very Large Array. We have obtained sensitive upper limits on 3.6cm emission from 2MASSW J1207334-393254, TWA~5B and SSSPM J1102-3431, all of which are likely members of the $\sim$8-Myr-old TW Hydrae association. We derive constraints on the magnetic field st

  71. Dumitru M. Ghilencea, Hyun Min Lee, Kai Schmidt-Hoberg

    We perform a detailed analysis of one-loop corrections to the self-energy of the (off-shell) gauge bosons in six-dimensional N=1 supersymmetric gauge theories on orbifolds. After discussing the Abelian case in the standard Feynman diagram approach, we extend the analysis to the non-Abelian case by employing the method of an orbifold-compatible one-loop effec

  72. W. Yi, L. -M. Duan

    We map out the detailed phase diagram of a trapped ultracold Fermi gas with population imbalance across a wide Feshbach resonance. We show that under the local density approximation, the properties of the atoms in any (anisotropic) harmonic traps are universally characterized by three dimensionless parameters: the normalized temperature, the dimensionless in

  73. Daniel Dugger

    This paper corrects a small mistake in a paper of Dwyer-Kan, and uses this to identify homotopy function complexes in a model category with the nerves of certain categories of zig-zags.

  74. Johanna Knapp, Harun Omer

    We present a method to compute the full non-linear deformations of matrix factorizations for ADE minimal models. This method is based on the calculation of higher products in the cohomology, called Massey products. The algorithm yields a polynomial ring whose vanishing relations encode the obstructions of the deformations of the D-branes characterized by the

  75. Boaz Tsaban, Lyubomyr Zdomskyy

    Using a dictionary translating a variety of classical and modern covering properties into combinatorial properties of continuous images, we get a simple way to understand the interrelations between these properties in ZFC and in the realm of the trichotomy axiom for upward closed families of sets of natural numbers. While it is now known that the answer to t

  76. Martin Kilbinger, Peter Schneider, Tim Eifler

    Aims. We quantify the mixing of the measured cosmic-shear E- and B-modes caused by the lack of shear-correlation measurements on small and large scales, arising from a lack of close projected galaxy pairs and the finite field size, respectively. Methods. We calculate the aperture-mass statistics <M_{ap, perp}^2> and the E-/B-mode shear-correlation functions

  77. G. Lusztig

    Let i be a homomorphism of the multiplicative group into a connected reductive algebraic group over C. Let G^i be the centralizer of the image i. Let LG be the Lie algebra of G and let L_nG (n integer) be the summands in the direct sum decomposition of LG determined by i. Assume that n is not zero. For any G^i-orbit O in L_nG and any irreducible G^i-equivari

  78. Pulak Ranjan Giri

    We study the asymptotic quasi-normal modes for the scalar perturbation of the non-commutative geometry inspired Schwarzschild black hole in (3+1) dimensions. We have considered $M\geq M_0$, which effectively correspond to a single horizon Schwarzschild black hole with correction due to non-commutativity. We have shown that for this situation the real part of

  79. Jan, Broekaert

    The validity of the Weak Equivalence Principle relative to a local inertial frame is detailed in a scalar-vector gravitation model with Lorentz-Poincaré type interpretation. Given the previously established first Post-Newtonian concordance of dynamics with General Relativity, the principle is to this order compatible with GRT. The gravitationally modified Lo

  80. Robert Conte

    Most evolution equations %or wave equations are partially integrable and, in order to explicitly integrate all possible cases, there exist several methods of complex analysis, but none is optimal. The theory of Nevanlinna and Wiman-Valiron on the growth of the meromorphic solutions gives predictions and bounds, but it is not constructive and restricted to me

  81. S. -T. Wu, C. -H. Pao, S. -K. Yip

    We study the pairing between Fermions of different masses, especially at the unitary limit. At equal populations, the thermodynamic properties are identical with the equal mass case provided an appropriate rescaling is made. At unequal populations, for sufficiently light majority species, the system does not phase separate. For sufficiently heavy majority sp

  82. Saikat Chatterjee, Amitabha Lahiri, Partha Guha

    The generalized vector is defined on an $n$ dimensional manifold. Interior product, Lie derivative acting on generalized $p$-forms, $-1\le p\le n$ are introduced. Generalized commutator of two generalized vectors are defined. Adding a correction term to Cartan&#39;s formula the generalized Lie derivative&#39;s action on a generalized vector field is defined.

  83. S P Dawson, C J Fewster

    The quantized Dirac field is known, by a result of Fewster and Verch, to satisfy a Quantum Weak Energy Inequality (QWEI) on its averaged energy density along time-like curves in arbitrary four-dimensional globally hyperbolic spacetimes. However, this result does not provide an explicit form for the bound. By adapting ideas from the earlier work, we give a si

  84. P. Gegenwart, T. Westerkamp, C. Krellner, Y. Tokiwa

    We report thermodynamic measurements in a magnetic-field-driven quantum critical point of a heavy fermion metal, YbRh$_2$Si$_2$. The data provide evidence for an energy scale in the equilibrium excitation spectrum, that is in addition to the one expected from the slow fluctuations of the order parameter. Both energy scales approach zero as the quantum critic

  85. Qing-Guo Huang, Miao Li, Jian-Huang She

    WMAP three-year data favors a red power spectrum at the level of 2 standard deviations, which provides a stringent constraint on the inflation models. In this note we use this data to constrain brane inflation models and find that KKLMMT model can not fit WMAP+SDSS data at the level of 1 standard deviation and a fine-tuning, eight parts in thousand at least,

  86. Laurent Freidel

    In this work we discuss an analytic approach towards the solution of pure Yang-Mills theory in 3+1 dimensional spacetime which strongly suggests that the recent strategy already applied to pure Yang-Mills theory in 2+1 can be extended to 3+1 dimensions. We show that the local gauge invariant variables introduced by Bars gives a natural generalisation to any

  87. A. Fuzfa, J. -M. Alimi

    We investigate the possibility that dark energy does not couple to gravitation in the same way than ordinary matter, yielding a violation of the weak and strong equivalence principles on cosmological scales. We build a transient mechanism in which gravitation is pushed away from general relativity by a Born-Infeld gauge interaction acting as an &#34;Abnormal

  88. Oliver J. Rosten

    Within the framework of a manifestly gauge invariant exact renormalization group for SU(N) Yang-Mills, we derive a simple expression for the expectation value of an arbitrary gauge invariant operator. We illustrate the use of this formula by computing the O(g^2) correction to the rectangular, Euclidean Wilson loop with sides T >> L. The standard result is tr

  89. C. S. Liu, H. G. Luo, W. C. Wu

    Using a nonlinear Schrödinger equation including short-range two-body attraction and three-body repulsion, we investigate the spatial distribution of indirect excitons in semiconductor coupled quantum wells. The results obtained can interpret the experimental phenomenon that annular exciton cloud first contracts then expands when the number of confined excit

  90. Monika Moscibrodzka, Tapas K. Das, Bozena Czerny

    The material accreting onto Sgr A* most probably comes from the nearby stars. We analyze the pattern of this flow at distances of a fraction of a parsec and we argue that the net angular momentum of this material is low but non-negligible, and the initially supersonic disk accretion changes into subsonic flow with constant angular momentum. Next we estimate

  91. Jan Derezinski, Wojciech De Roeck

    We study a class of self-adjoint operators defined on the direct sum of two Hilbert spaces: a finite dimensional one called sometimes a ``small subsystem&#39;&#39; and an infinite dimensional one -- a ``reservoir&#39;&#39;. The operator, which we call a ``Friedrichs Hamiltonian&#39;&#39;, has a small coupling constant in front of its off-diagonal term. It is

  92. G. Baym, J. -P. Blaizot, F. Gelis, T. Matsui

    We show how the Landau-Pomeranchuk-Migdal effect on photon production rates in a quark-gluon plasma can be derived via the usual Boltzmann equation. To do this, we first derive the electromagnetic polarization tensor using linear response theory, and then formulate the Boltzmann equation including the collisions mediated by soft gluon exchanges. We then iden

  93. Andrew P. Rasmussen, Steven M. Kahn, Frits Paerels, Jan Willem den Herder

    In a series of papers, Nicastro et al. have reported the detection of z>0 OVII absorption features in the spectrum of Mrk421 obtained with the Chandra Low Energy Transmission Grating Spectrometer (LETGS). We evaluate this result in the context of a high quality spectrum of the same source obtained with the Reflection Grating Spectrometer (RGS) on XMM-Newton.

  94. Kaoru Hagiwara, Ken-ichi Hikasa, Hiroshi Yokoya

    Parity-odd asymmetries in the decay angular distribution of a W boson produced with a hard jet in p\bar{p} collisions arise only from QCD rescattering effects. If observed, these asymmetries will provide a first demonstration that perturbative QCD calculation is valid for the absorptive part of scattering amplitudes. We propose a simple observable to measure

  95. Kunihiko Terasaki

    Production of neutral and doubly charged partners, $\hat F_I^0$ and $\hat F_I^{++}$, of $ D_{s0}^+(2317)$ as a charm-strange four-quark meson is studied in relation to observations of $D_{s0}^+(2317)$. It is discussed that observation of $\hat F_I^{++}$ in inclusive $e^+e^-\to c\bar c$ is difficult but it might be observed in $B_u^+\to D_s^+π^+D^-$. Observat

  96. B. Grossan, G. F. Smoot

    We describe data reduction and analysis of fluctuations in the cosmic far-IR background (CFIB) in observations with the Multiband Imaging Photometer for Spitzer (MIPS) instrument 160 micron detectors. We analyzed observations of an 8.5 square degree region in the Lockman Hole, part of the largest low-cirrus mapping observation with this instrument. We measur

  97. Boris Hasselblatt, James Propp

    For projectivizations of rational maps Bellon and Viallet defined the notion of algebraic entropy using the exponential growth rate of the degrees of iterates. We want to call this notion to the attention of dynamicists by computing algebraic entropy for certain rational maps of projective spaces (Theorem 6.2) and comparing it with topological entropy (Theor

  98. Sudipto Guha, Boulos Harb

    This paper addresses the problem of finding a B-term wavelet representation of a given discrete function $f \in \real^n$ whose distance from f is minimized. The problem is well understood when we seek to minimize the Euclidean distance between f and its representation. The first known algorithms for finding provably approximate representations minimizing gen

  99. Sinem Binicioglu, M. Ali Can, Alexander A. Klyachko, Alexander S. Shumovsky

    Using a single spin-1 object as an example, we discuss a recent approach to quantum entanglement. The key idea of the approach consists in presetting of basic observables in the very definition of quantum system. Specification of basic observables defines the dynamic symmetry of the system. Entangled states of the system are then interpreted as states with m

  100. S. Yasui, A. Hosaka

    We discuss the stability of strangelets by considering dynamical chiral symmetry breaking. For quark droplets of finite volume, we formulate the Nambu--Jona-Lasinio model with a basis set of the quark wave functions in the chiral bag model. Chiral symmetry breaking for the finite volume bag is discussed in a mean field approximation. Effects of the pion clou