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November 2005 arXiv papers — page 32

Showing 3,1013,200 of 4,366 papers

  1. Yuri A. Shibanov, Sergei V. Zharikov, Viktoria N. Komarova, Nobuyuki Kawai

    We carried out a deep subarcsecond BRI imaging of the two middle-aged pulsars to establish their properties in the optical range. Both pulsars are detected at >10 sigma level. Geminga is for the first time reliably detected in the I band with a magnitude of 25.10+/-0.14. We also reanalyze archival ESO/NTT and HST broadband data and find that some published f

  2. Casey Papovich, L. A. Moustakas, M. Dickinson, E. Le Floc'h

    We investigate the properties of massive galaxies at z=1-3.5 using HST observations, ground-based near-IR imaging, and Spitzer Space Telescope observations at 3-24 micron. We identify 153 distant red galaxies (DRGs) with J-K > 2.3 mag (Vega) in the southern GOODS field. This sample is approximately complete in stellar mass for passively evolving galaxies abo

  3. K. Pottschmidt, I. Kreykenbohm, J. Wilms, W. Coburn

    We present an analysis of the 2-150 keV spectrum of the transient X-ray pulsar V0332+53 taken with the Rossi X-Ray Timing Explorer (RXTE) in 2004 December. We report on the detection of three cyclotron resonance features at 27, 51, and 74 keV in the phase-averaged data, corresponding to a polar magnetic field of 2.7 x 10^12 G. After 4U0115+63, this makes V03

  4. A. Kashlinsky

    Cosmic infrared background (CIB) contains information about galaxy luminosities over the entire history of the Universe and can be a powerful diagnostic of the early populations otherwise inaccessible to telescopic studies. Its measurements are very difficult because of the strong IR foregrounds from the Solar system and the Galaxy. Nevertheless, substantial

  5. Rosalba Perna, Enrico Bozzo, Luigi Stella

    Accreting X-Ray Binaries display a wide range of behaviours. Some of them are observed to spin up steadily, others to alternate between spin-up and spin-down states, sometimes superimposed on a longer trend of either spin up or spin down. Here we interpret this rich phenomenology within a new model of the disk-magnetosphere interaction. Our model, based on t

  6. Joel N. Bregman, Eric D. Miller, Alex E. Athey, Jimmy A. Irwin

    Early-type galaxies often contain a hot X-ray emitting interstellar medium (3-8E6 K) with an apparent radiative cooling time much less than a Hubble time. If unopposed by a heating mechanism, the gas will radiatively cool to temperatures <= 10E4 K at a rate proportional to L_X/T_X, typically 0.03-1 M_solar yr^-1. We can test if gas is cooling through the 3E5

  7. S. Casassus, G. Cabrera, F. Forster, T. J. Pearson

    The spectral energy distribution of the dark cloud LDN1622, as measured by Finkbeiner using WMAP data, drops above 30GHz and is suggestive of a Boltzmann cutoff in grain rotation frequencies, characteristic of spinning dust emission. LDN1622 is conspicuous in the 31 GHz image we obtained with the Cosmic Background Imager, which is the first cm-wave resolved

  8. E. Egami, G. Neugebauer, B. T. Soifer, K. Matthews

    In order to examine the relative importance of powerful starbursts and Compton-thick AGNs in NGC 6240, we have obtained mid-infrared images and low-resolution spectra of the galaxy with sub-arcsecond spatial resolution using the Keck Telescopes. Despite the high spatial resolution (~200 pc) of our data, no signature of the hidden AGNs has been detected in th

  9. D. Paulson, J. Allred, R. Anderson, S. Hawley

    We present optical spectra of a flare on Barnard&#39;s star. Several photospheric as well as chromospheric species were enhanced by the flare heating. An analysis of the Balmer lines shows that their shapes are best explained by Stark broadening rather than chromospheric mass motions. We estimate the temperature of the flaring region in the lower atmosphere

  10. Christian Leipski, Nicola Bennert

    Interactions between the radio jet and the optical emission of the narrow-line region (NLR) are a well known phenomenon in Seyfert galaxies. Here, we present the study of possible jet-NLR interactions in five radio-quiet PG quasars with double or triple radio structure. High spatial and spectral resolution observations were carried out in the Hbeta-[OIII]500

  11. Nicola Bennert, Bruno Jungwiert, Stefanie Komossa, Martin Haas

    We study the narrow-line region (NLR) of the Seyfert-2 galaxy NGC 1386 by means of long-slit spectroscopy obtained with FORS1 at the VLT. We use the galaxy itself for subtracting the stellar template, applying reddening corrections to fit the stellar template to the spectra of the NLR. The continuum gets steadily redder towards the nucleus. The spatial distr

  12. G. Bihain, R. Rebolo, V. J. S. Bejar, J. A. Caballero

    We present results of an optical and near-infrared (IR) 1.8 deg^2 survey in the Pleiades open cluster to search for substellar objects. From optical I-band images from the CFHT and J-band images from the 3.5 m CAHA Telescope, we identify 18 faint and very red L brown dwarf candidates, with I> 20.9 and I-J> 3.2. The follow-up observations of nine objects in t

  13. Eric Armengaud, Guenter Sigl, Francesco Miniati

    Nearby sources of cosmic rays up to a ZeV(=10^21 eV) could be observed with a multi-messenger approach including secondary gamma-rays and neutrinos. If cosmic rays above ~10^18 eV are produced in magnetized environments such as galaxy clusters, the flux of secondary gamma-rays below ~1 TeV can be enhanced up to several orders of magnitudes compared to unmagn

  14. G. Fabbiano

    Chandra observations show the importance of the X-ray band for studying the evolution of galaxies. Binary X-ray sources are an easily detectable tracer of the stellar population. Chandra studies of these populations are giving us insights into the nature and formation of these binaries, and provide the basis for diagnostics of galaxy evolution. With Chandra

  15. G. Fabbiano

    The IAU Symposium 230, Populations of High Energy Sources in Galaxies, has been a wide-spectrum affair, with talks discussing results from the soft X-ray to the Gamma-ray range on virtually the entire universe, from our Galaxy to the high redshift regions when first galaxies emerged. I do not name any presenter in this summary, but concentrate on themes and

  16. G. Fabbiano

    Today&#39;s sensistive, high resolution Chandra X-ray observations allow the study of many populations of X-ray sources. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, and provide the means for classifying the X-ray sources and probing their evolution. While overall stellar mass drive

  17. P. Padovani

    The Astrophysical Virtual Observatory (AVO) initiative, jointly funded by the European Commission and six European organisations, had the task of creating the foundations of a regional scale infrastructure by conducting a research and demonstration programme on the VO scientific requirements and necessary technologies. The AVO project is now formally conclud

  18. I. Kreykenbohm, N. Mowlavi, K. Pottschmidt, J. Wilms

    We present the spectral and temporal analysis of the 2004/2005 outburst of the transient X-ray pulsar V0332+53 as observed with Integral. After the discovery of the third cyclotron line in phase averaged spectra (Kreykenbohm et al 2005, Pottschmidt et al 2005), detailed pulse phase spectroscopy revealed remarkably little variability of the cyclotron lines th

  19. Georges Meynet, Andre Maeder

    Using single star models including the effects of shellular rotation with and without magnetic fields, we show that massive stars at solar metallicity with initial masses lower than about 20-25 M$_\odot$ and with an initial rotation above $\sim 350$ km s$^{-1}$ likely reach the critical velocity during their Main-Sequence phase. This results from the efficie

  20. I. Agudo, T. P. Krichbaum, U. Bach, A. Pagels

    The Global mm-VLBI Array is at present the most sensitive 3 mm-VLBI interferometer and provides images of up to 40 micro-arcsecond resolution. Using this array, we have monitored the rotation of the innermost jet in the quasar NRAO 150, which shows an angular speed of ~ 7 deg./yr. Future 3 mm arrays could include additional stations like ALMA, GBT, LMT, CARM

  21. V. Lazaro, R. Saxton, A. M. Read, M. P. Esquej

    The low background, good spatial resolution and great sensitivity of the EPIC-pn camera on XMM-Newton give useful limits for the detection of extended sources even during the short exposures made during slewing maneouvers. In this paper we attempt to illustrate the potential of the XMM-Newton slew survey as a tool for analysing flux-limited samples of cluste

  22. Corinne Charbonnel, Suzanne Talon

    The Sun&#39;s rotation profile and lithium content have been difficult to understand in the context of conventional models of stellar evolution. Classical hydrodynamical models predict that the solar interior must rotate highly differentially, in disagreement with observations. It has recently been shown that internal waves produced by convection in solar-ty

  23. Guillem Anglada, Jordi Torra

    Context:Very precise planned space astrometric missions and recent improvements on imaging capabilities require a detailed review of the assumptions of classical astrometric modeling. Aims:We show that Light-Travel Time must be taken into account to model the kinematics of astronomical objects in nonlinear motion, even at stellar distances. Methods:A closed

  24. P. Miocchi

    In the construction of multi-mass King-Michie models of globular clusters, an approximated central energy equipartition between stars of different masses is usually imposed by scaling the velocity parameter of each mass class inversely with the stellar mass, as if the distribution function were isothermal. In this paper, this &#39;isothermal approximation&#3

  25. R. Bernabei, P. Belli, F. Montecchia, F. Nozzoli

    In this paper another class of Dark Matter candidate particles: the pseudoscalar and scalar light bosonic candidates, is discussed. Particular care is devoted to the study of the processes for their detection (which only involves electrons and photons/X-rays) in a suitable underground experimental set-up. For this purpose the needed calculations are develope

  26. W. R. F. Dent, J. M. Torrelles, M. Osorio, N. Calvet

    We present 7 mm and 3.5 cm wavelength continuum observations toward the Herbig AeBe star HD169142 performed with the Very Large Array (VLA) with an angular resolution of ~1&#34;. We find that this object exhibits strong (~4.4 mJy), unresolved (~1&#34;) 7 mm continuum emission, being one of the brightest isolated Herbig AeBe stars ever detected with the VLA a

  27. Wlodzimierz Godlowski, Katarzyna Bajan, Piotr Flin

    We discuss the distribution of radial velocities of galaxies belonging to the Local Group. Two independent samples of galaxies as well as several methods of reduction from the heliocentric to the galactocentric radial velocities are explored. We applied the power spectrum analysis using the Hann function as a weighting method, together with the jackknife err

  28. D. R. Lorimer

    We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1700. There are now 80 binary and millisecond pulsars associated with the disk of our Galax

  29. K. Georgieva, B. Kirov, E. Gavruseva, J. Javaraiah

    The most geoeffective solar drivers are magnetic clouds - a subclass of coronal mass ejections (CME&#39;s) distinguished by the smooth rotation of the magnetic field inside the structure. The portion of CME&#39;s that are magnetic clouds is maximum at sunspot minimum and mimimum at sunspot maximum. This portion is determined by the amount of helicity carried

  30. Lorenzo Zaninetti

    The dichotomy between a universal mass function (IMF) and a variable IMF which depends on local physical parameters characterises observational and theoretical stellar astronomy. In this contribution the available distributions of probability are briefly reviewed. The physical nature of two of them, gamma variate and lognormal, is then explained once the fra

  31. C. Maier, S. J. Lilly, C. M. Carollo, K. Meisenheimer

    The 1<z<2 redshift window hosts the peak of the star formation and metal production rates. Studies of the metal content of the star forming galaxies at these epochs are however sparse. We report VLT-ISAAC near-infrared spectroscopy for a sample of five [OII]-selected, M_B,AB<-21.5, z~1.4 galaxies, by which we measured Hbeta and [OIII]5007 emission line fluxe

  32. Ayesha Begum, Jayaram. N. Chengalur, I. D. Karachentsev, S. S. Kaisin

    We compare the gas distribution, kinematics and the current star formation in a sample of 10 very faint (-13.37 < M_B < -9.55) dwarf galaxies. For 5 of these galaxies we present fresh, high sensitivity, GMRT HI 21cm observations. For all our galaxies we construct maps of the HI column density at a constant linear resolution of ~300 pc; this forms an excellen

  33. G. Mark Voit, Scott T. Kay, Greg L. Bryan

    The radial entropy profile of the hot gas in clusters of galaxies tends to follow a power law in radius outside of the cluster core. Here we present a simple formula giving both the normalization and slope for the power-law entropy profiles of clusters that form in the absence of non-gravitational processes such as radiative cooling and subsequent feedback.

  34. Eric W. Peng, Patrick Cote, Andres Jordan, John P. Blakeslee

    We use HST/ACS imaging of 100 early-type galaxies in the ACS Virgo Cluster Survey to investigate the nature of diffuse star clusters (DSCs). Compared to globular clusters (GCs), these star clusters have moderately low luminosities (M_V > -8) and a broad distribution of sizes (3 < r_h < 30 pc), but they are principally characterized by their low mean surface

  35. M. D. Silverstone, M. R. Meyer, E. E. Mamajek, D. C. Hines

    We present data obtained with the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope (Spitzer) for a sample of 74 young (t < 30 Myr old) Sun-like (0.7 < M(star)/M(Sun) < 1.5) stars. These are a sub-set of the observations that comprise the Spitzer Legacy science program entitled the Formation and Evolution of Planetary Systems (FEPS). Using IRAC

  36. Richard J. Elston, Anthony H. Gonzalez, Eric McKenzie, Mark Brodwin

    Using the Florida Multi-object Imaging Near-IR grism Observational Spectrometer (FLAMINGOS), we have conducted the FLAMINGOS Extragalactic Survey (FLAMEX), a deep imaging survey covering 7.1 square degrees within the 18.6 sq. deg NOAO Deep Wide-Field Survey (NDWFS) regions. FLAMEX is the first deep, wide-area near-infrared survey to image in both the J and K

  37. Nevin N. Weinberg, Lars Bildsten, Hendrik Schatz

    We solve for the evolution of the vertical extent of the convective region of a neutron star atmosphere during a Type I X-ray burst. The convective region is well-mixed with ashes of nuclear burning and its extent determines the rise time of the burst light curve. Using a full nuclear reaction network, we show that the maximum vertical extent of the convecti

  38. Martin G. Haehnelt, Melvyn B. Davies, Martin J. Rees

    Attempts of Magain et al (2005) to detect the host galaxy of the bright QSO HE0450--2958 have not been successful. We suggest that the supermassive black hole powering the QSO was ejected from the observed ULIRG at the same redshift and at 1.5 arcsec distance. Ejection could have either be caused by recoil due to gravitational wave emission from a coalescing

  39. Christopher Lindsay Naumann, Gisela Anton, Kay Graf, Juergen Hoessl

    In order to study the possibility of acoustic detection of ultra-high energy neutrinos in water, our group is planning to deploy and operate an array of acoustic sensors using the ANTARES Neutrino telescope in the Mediterranean Sea. Therefore, acoustic sensor hardware has to be developed which is both capable of operation under the hostile conditions of the

  40. Y. Gupta, D. Mitra, D. A. Green, A. Acharyya

    We report the discovery of a young pulsar associated with the supernova remnant G21.5-0.9, using the Giant Metrewave Radio Telescope (GMRT) located near Pune, India. Discovered at a frequency of 610 MHz, J1833-1034 has a period of 61.86 ms and a period derivative of $2.0 \times 10^{-13}$, making it similar to other known young pulsars. The characteristic age

  41. J. Cuadra, S. Nayakshin, V. Springel, T. Di Matteo

    (ABRIDGED) We present in detail our new 3D numerical models for the accretion of stellar winds on to Sgr A*. In our most sophisticated models, we put stars on realistic orbits around Sgr A*, include `slow&#39; winds (300 km/s), and account for radiative cooling. We first model only one phase `fast&#39; stellar winds (1000 km/s). For wind sources fixed in spa

  42. T. Heinemann, W. Dobler, A. Nordlund, A. Brandenburg

    An efficient algorithm for calculating radiative transfer on massively parallel computers using domain decomposition is presented. The integral formulation of the transfer equation is used to divide the problem into a local but compute-intensive part for calculating the intensity and optical depth integrals, and a nonlocal part for communicating the intensit

  43. Helge Glockner

    We prove an implicit function theorem for C^k-maps from arbitrary topological vector spaces over valued fields to Banach spaces (for k at least 2). As a tool, we show the C^k-dependence of fixed points on parameters for suitable families of contractions of a Banach space. Similar results are obtained for k times strictly differentiable maps, and for k times

  44. Jonathan Oppenheim, Andreas Winter

    If two parties share an unknown quantum state, one can ask how much quantum communication is needed for party A to send her share to party B. Recently, it was found that the number of qubits which should be sent is given by the conditional entropy. This quantifies the notion of partial information, and it can even be negative. Here, we not only demand that A

  45. Siu A. Chin

    The structure of symplectic integrators up to fourth-order can be completely and analytical understood when the factorization (split) coefficents are related linearly but with a uniform nonlinear proportional factor. The analytic form of these {\it extended-linear} symplectic integrators greatly simplified proofs of their general properties and allowed easy

  46. Betty I. Bezverkhny

    Angular correlations between produced high pT Xi baryons and unidentified charged and neutral particles are observed in high-tower-triggered (on a large electromagnetic energy deposit) s^(1/2)=200 GeV p+p collisions. This trigger favors events with higher average multiplicity than those in minimum bias. These events are likely to contain jets. The average mu

  47. Jan Derezinski

    Lecture notes of a minicourse given at the Summer School on Large Coulomb Systems - QED in Nordfjordeid, 2003, devoted to representations of the CCR and CAR. Quasifree states, the Araki-Woods and Araki-Wyss representations, and the lattice of von Neumenn algebras in a bosonic/fermionic Fock space are discussed in detail.

  48. Melanie Becker, Keshav Dasgupta, Sheldon Katz, Anke Knauf

    We continue our study of geometric transitions in type II and heterotic theories. In type IIB theory we discuss an F-theory setup which clarifies many of our earlier assumptions and allows us to study gravity duals of N = 1 gauge theories with arbitrary global symmetry group G. We also point out the subtle differences between global and local metrics, and sh

  49. S. J. Akhtarshenas

    We study the boson-parafermion entanglement of the parasupersymmetric coherent states of the harmonic oscillator and derive the degree of entanglement in terms of the concurrence. The conditions for obtaining the maximal entanglement is also examined, and it is shown that in the usual supersymmetry situation we can obtain maximally entangled Bell states.

  50. Loren Hoffman, Abraham Loeb

    The quasar HE0450-2958 was recently discovered to reside ~7kpc away from a galaxy that was likely disturbed by a recent merger. The lack of a massive spheroid of stars around the quasar raised the unlikely suggestion that it may have formed in a dark galaxy. Here we explain this discovery as a natural consequence of a dynamical kick imparted to the quasar as

  51. Mark D. Roberts

    It is shown that constant galactic rotation curves require a logarithmic potential in both newtonian and relativistic theory. In newtonian theory the density vanishes asymptotically, but there are a variety of possibilities for perfect fluid einstein theory.

  52. Volker Braun, Sakura Schafer-Nameki

    We construct Gepner models in terms of coset conformal field theories and compute their twisted equivariant K-theories. These classify the D-brane charges on the associated geometric backgrounds and therefore agree with the topological K-theories. We show this agreement for various cases, in particular the Fermat quintic.

  53. Andre H. Hoang, Pedro Ruiz-Femenia

    The vNRQCD Lagrangian for colored heavy scalar fields in the fundamental representation of QCD and the renormalization group analysis of the corresponding operators are presented. The results are an important ingredient for renormalization group improved computations of scalar-antiscalar bound state energies and production rates at next-to-next-to-leading-lo

  54. L. H. Li, P. Ventura, S. Basu, S. Sofia

    A high-precision two-dimensional stellar evolution code has been developed for studying solar variability due to structural changes produced by varying internal magnetic fields of arbitrary configurations. Specifically, we are interested in modeling the effects of a dynamo-type field on the detailed internal structure and on the global parameters of the Sun.

  55. J. C. Montero, C. C. Nishi, V. Pleitez, O. Ravinez

    We consider a model with soft CP violation which accommodate the CP violation in the neutral kaons even if we assume that the Cabibbo-Kobayashi-Maskawa mixing matrix is real and the sources of CP violation are three complex vacuum expectation values and a trilinear coupling in the scalar potential. We show that for some reasonable values of the masses and ot

  56. S. S. Tsygankov, A. A. Lutovinov, E. M. Churazov, R. A. Sunyaev

    We present results of observations of the transient X-ray pulsar V0332+53 performed during a very powerful outburst in Dec, 2004 -- Feb, 2005 with the INTEGRAL and RXTE observatories in a wide (3-100 keV) energy band. A cyclotron resonance scattering line at an energy of ~26 keV has been detected in the source spectrum together with its two higher harmonics

  57. Terence Tao, Van Vu

    Consider a random sum $η_1 v_1 + ... + η_n v_n$, where $η_1,...,η_n$ are i.i.d. random signs and $v_1,...,v_n$ are integers. The Littlewood-Offord problem asks to maximize concentration probabilities such as $¶(η_1 v_1 + ... + η_n v_n = 0)$ subject to various hypotheses on the $v_1,...,v_n$. In this paper we develop an \emph{inverse} Littlewood-Offord theore

  58. Julius Kuti

    Bosonic string formation in gauge theories is reviewed with particular attention to the confining flux in lattice QCD and its string theory description. Recent results on the Casimir energy of the ground state and the string excitation spectrum are analyzed in the Dirichlet string limit of large separation between static sources. The closed string-soliton (t

  59. M. Angeles Serrano, Ana Maguitman, Marian Boguna, Santo Fortunato

    The understanding of the immense and intricate topological structure of the World Wide Web (WWW) is a major scientific and technological challenge. This has been tackled recently by characterizing the properties of its representative graphs in which vertices and directed edges are identified with web-pages and hyperlinks, respectively. Data gathered in large

  60. Richard Easther, Eugene A. Lim, Matthew R. Martin

    We consider the long standing puzzle of how to obtain meaningful probabilities in eternal inflation. We demonstrate a new algorithm to compute the probability distribution of pocket universe types, given a multivacua inflationary potential. The computed probability distribution is finite and manifestly gauge-independent. We argue that in some scenarios this

  61. J. Santhanam, V. M. Kenkre, V. V. Konotop

    It is shown that a Bose-Fermi mixture of a degenerate gas of spin-polarized fermions, whose number significantly exceeds the number of bosons, embedded in a strongly anisotropic trap, is described by the one-dimensional coupled nonlinear Schrodinger equation for the boson component and the wave equation with external source for the fermion component. Dependi

  62. Tonatiuh Matos, Jose-Ruben Luevano, Hugo Garcia-Compean

    We start with a particular cosmological model derived from type IIB supergravity theory with fluxes, where usually the dilaton is interpreted as a Quintessence field. Instead of that, in this letter we interpret the dilaton as the dark matter of the universe. With this alternative interpretation we find that in this supergravity model gives a similar evoluti

  63. The FOCUS collaboration, J. M. Link

    Using data collected by the FOCUS experiment at Fermilab, we present a new measurement of the charm semileptonic branching ratio BR(D+ -> rho0 mu+ nu)/BR(D+ -> K*0 mu+ nu). From a sample of 320+-44 and 11372+-161 D+ -> rho0 mu+ nu and D+ -> K*0 mu+ nu events respectively, we find BR(D+ -> rho0 mu+ nu)/BR(D+ -> K*0 mu+ nu)=0.041+-0.006(stat)+-0.004(syst).

  64. Frank Wilczek

    Our understanding of ordinary matter is remarkably accurate and complete, but it is based on principles that are very strange and unfamiliar. As I&#39;ll explain, we&#39;ve come to understand matter to be a Music of the Void, in a remarkably literal sense. Just as we physicists finalized that wonderful understanding, towards the end of the twentieth century,

  65. Alex G. Dias, J. C. Montero, V. Pleitez

    We show that in 3-3-1 models there exist a natural relation among the $SU(3)_L$ coupling constant $g$, the electroweak mixing angle $θ_W$, the mass of the $W$, and one of the vacuum expectation values, which implies that those models can be realized at low energy scales and, in particular, even at the electroweak scale. So that, being that symmetries realize

  66. Goren Gordon, Gustavo Rigolin

    A generalized teleportation protocol (GTP) for N qubits is presented, where the teleportation channels are non-maximally entangled and all the free parameters of the protocol are considered: Alice&#39;s measurement basis, her sets of acceptable results, and Bob&#39;s unitary operations. The full range of Fidelity (F) of the teleported state and the Probabili

  67. Akifumi Sako, Toshiya Suzuki

    We investigate the Seiberg-Witten monopole equations on noncommutative(N.C.) R^4 at the large N.C. parameter limit, in terms of the equivariant cohomology. In other words, N}=2 supersymmetric U(1) gauge theories with hypermultiplet on N.C. R}^4 are studied. It is known that after topological twisting partition functions of N}>1 supersymmetric theories on N.C

  68. Robert B. Mann, Donald Marolf

    A new local, covariant ``counter-term&#39;&#39; is used to construct a variational principle for asymptotically flat spacetimes in any spacetime dimension $ d \ge 4$. The new counter-term makes direct contact with more familiar background subtraction procedures, but is a local algebraic function of the boundary metric and Ricci curvature. The corresponding a

  69. R. Brustein, S. P. de Alwis

    We explore the possibility that quantum cosmology considerations could provide a selection principle in the landscape of string vacua. We propose that the universe emerged from the string era in a thermally excited state and determine, within a mini-superspace model, the probability of tunneling to different points on the landscape. We find that the potentia

  70. Merab Gogberashvili

    The model where the universe is considered as an expanding spherical 3-brane allows us to explain its expansion rate without a dark energy component. In this scenario the computed redshift that corresponds to the transition from cosmic deceleration to acceleration is in a good agreement with observations.

  71. D. Soler

    The concept of rigid reference frame and of constricted spatial metric, given in the previous work [\emph{Class. Quantum Grav.} {\bf 21}, 3067,(2004)] are here applied to some specific space-times: In particular, the rigid rotating disc with constant angular velocity in Minkowski space-time is analyzed, a new approach to the Ehrenfest paradox is given as wel

  72. Harald Luschgy, Gilles Pagès

    We derive high-resolution upper bounds for optimal product quantization of pathwise contionuous Gaussian processes respective to the supremum norm on [0,T]^d. Moreover, we describe a product quantization design which attains this bound. This is achieved under very general assumptions on random series expansions of the process. It turns out that product quant

  73. Wael Abushammala, Alberto Torchinsky

    In this paper we consider the $X_s$ spaces that lie between $H^1(R^n)$ and $L^1(R^n)$. We discuss the interpolation properties of these spaces, and the behavior of maximal functions and singular integrals acting on them.

  74. Akhlesh Lakhtakia, Tom G. Mackay

    The dyadic Green function for a homogeneous electromagnetic medium inspired by the spatiotemporally nonhomogeneous constitutive equations of gravitationally affected vacuum is derived.

  75. Holger Gies, Klaus Klingmuller

    We present new results for Casimir forces between rigid bodies which impose Dirichlet boundary conditions on a fluctuating scalar field. As a universal computational tool, we employ worldline numerics which builds on a combination of the string-inspired worldline approach with Monte-Carlo techniques. Worldline numerics is not only particularly powerful for i

  76. G. E. Bruno, A. Dainese

    The NA57 experiment has measured the pt distributions of K0s, Lambda, and antiLambda particles in fixed-target Pb-Pb interactions at sqrt(s_{NN})=17.3 GeV as a function of the collision centrality. In this paper we study the central-to-peripheral nuclear modification factors and compare them to other measurements and to theoretical predictions.

  77. Daniel Nogradi

    A generalization of Nahm&#39;s equation has been recently conjectured by Basu and Harvey to be the BPS condition describing the bound state of a stack of M2-branes ending on an M5-brane. In this note exact solutions are presented for the proposed BPS equation - which is from the point of view of the M2-brane world-volume dynamics - with boundary conditions a

  78. R. Muto, H. En&#39;yo, M. Naruki, T. Tabaru

    Invariant mass spectra of e+e- pairs have been measured in 12 GeV p+A reactions to detect possible in-medium modification of vector mesons. Copper and carbon targets are used to study the nuclear-size dependence of e+e- invariant mass distributions. A significant excess on the low-mass side of the phi meson peak is observed in the low beta gamma (=beta/sqrt(

  79. J. Cleymans, H. Oeschler, K. Redlich, S. Wheaton

    One of the most remarkable results to emerge from heavy-ion collisions over the past two decades is the striking regularity shown by particle yields at all energies. This has led to several very successful proposals describing particle yields over a very wide range of beam energies, reaching from 1 A GeV up to 200 A GeV, using only one or two parameters. A s

  80. M. C. Gonzalez-Garcia, P. C. de Holanda, R. Zukanovich Funchal

    In this work we study the phenomenological consequences of the environment dependence of neutrino mass on solar and reactor neutrino phenomenology. Such dependence can be induced, for example, by Yukawa interactions with a light scalar particle which couples to neutrinos and matter and it is expected, among others, in mass varying neutrino scenarios. Under t

  81. F. Becattini, J. Manninen, M. Gazdzicki

    We present a detailed study of chemical freeze-out in p-p, C-C, Si-Si and Pb-Pb collisions at beam momenta of 158A GeV as well as Pb-Pb collisions at beam momenta of 20A, 30A, 40A and 80A GeV. By analyzing hadronic multiplicities within the statistical hadronization model, we have studied the parameters of the source as a function of the number of the partic

  82. M. Takahashi, J. Goto, K. Fukumura, D. Rilett

    Fast and slow magnetosonic shock formation is presented for stationary and axisymmetric magnetohydrodynamical (MHD) accretion flows onto a black hole. The shocked black hole accretion solution must pass through magnetosonic points at some locations outside and inside the shock location. We analyze critical conditions at the magnetosonic points and the shock

  83. A. Tricoli

    Since the current uncertainty on the structure of the proton affects the new physics discovery potential of LHC, the ATLAS collaboration is investigating methods to constrain this uncertainty over the whole LHC kinematic regime. The Standard Model processes such as direct photon, Z, W and inclusive jet productions are optimal candidates for this purpose.

  84. Pengjie Zhang

    A generic prediction of general relativity is that the cosmological linear density growth factor $D$ is scale independent. But in general, modified gravities do not preserve this signature. A scale dependent $D$ can cause time variation in gravitational potential at high redshifts and provides a new cosmological test of gravity, through early time integrated

  85. Simon F. Ross

    We find soliton solutions in five-dimensional gauged supergravity, where a circle degenerates smoothly in the core of the geometry. In the family of solutions we consider, we find no completely smooth supersymmetric solutions, but we find discrete families of non-supersymmetric solitons. We discuss the relation to previous studies of the asymptotically flat

  86. Alexander Unzicker

    Ernst Mach (1838-1916) suggested that the origin of gravitational interaction could depend on the presence of all masses in the universe. A corresponding hypothesis of Sciama (1953) on the gravitational constant, c^2/G = \sum m_i/r_i, is linked to Dicke&#39;s (1957) proposal of an electromagnetic origin of gravitation, a precursor of scalar-tensor-theories.

  87. Jie Sun, Yizhi Ge, Sheng Li

    We proposed an evolving network model constituted by the same nodes but different edges. The competition between nodes and different links were introduced. Scale free properties have been found in this model by continuum theory. Different network topologies can be generated by some tunable parameters. Simulation results consolidate the prediction.

  88. Wen-ling Huang, Xiao Zhang

    In a vacuum spacetime equips with the Bondi&#39;s radiating metric which is asymptotically flat at spatial infinity including gravitational radiation ({\bf Condition D}), we establish the relation between the ADM total linear momentum and the Bondi momentum. The relation between the ADM total energy and the Bondi mass in this case was established earlier in

  89. Minoru Eto, Youichi Isozumi, Muneto Nitta, Keisuke Ohashi

    We completely determine the moduli space M_{N,k} of k-vortices in U(N) gauge theory with N Higgs fields in the fundamental representation. Its open subset for separated vortices is found as the symmetric product (C x CP^{N-1})^k / S_k. Orbifold singularities of this space correspond to coincident vortices and are resolved resulting in a smooth moduli manifol

  90. Xiao Zhang

    When a spacetime takes Bondi radiating metric, and is vacuum and asymptotically flat at spatial infinity which ensures the positive mass theorem, we prove that the standard ADM energy-momentum is the past limit of the Bondi energy-momentum. We also derive a formula relating the ADM energy-momentum of any asymptotically flat spacelike hypersurface to the Bond

  91. Yaoyun Shi, Yufan Zhu

    We initiate the study of quantifying nonlocalness of a bipartite measurement by the minimum amount of classical communication required to simulate the measurement. We derive general upper bounds, which are expressed in terms of certain tensor norms of the measurement operator. As applications, we show that (a) If the amount of communication is constant, quan

  92. Yaoyun Shi, Luming Duan, Guifre Vidal

    We show how to efficiently simulate a quantum many-body system with tree structure when its entanglement is bounded for any bipartite split along an edge of the tree. This is achieved by expanding the {\em time-evolving block decimation} simulation algorithm for time evolution from a one dimensional lattice to a tree graph, while replacing a {\em matrix prod

  93. Igor L. Markov, Yaoyun Shi

    The treewidth of a graph is a useful combinatorial measure of how close the graph is to a tree. We prove that a quantum circuit with $T$ gates whose underlying graph has treewidth $d$ can be simulated deterministically in $T^{O(1)}\exp[O(d)]$ time, which, in particular, is polynomial in $T$ if $d=O(\log T)$. Among many implications, we show efficient simulat

  94. Alessandro Bacchetta

    I discuss the relation between the Qiu-Sterman effects on one hand and the Collins, Sivers and Boer-Mulders effects on the other hand. It was suggested before that some of these effects are in fact the same, thus providing interesting connections between transverse-momentum dependent twist-2 functions and collinear twist-3 functions. Here I propose an altern

  95. Sanil Unnikrishnan, T. R. Seshadri

    In this paper we consider a model of scalar-tensor theory of gravitation in which the scalar field, $ϕ$ determines the gravitational coupling G and has a Lagrangian of the form, $\mathcal{L}_ϕ =-V(ϕ)\sqrt{1 - \partial_μϕ\partial^μϕ}$. We study the cosmological consequence of this theory in the matter dominated era and show that this leads to a transition fro

  96. Hisham Sati

    Elliptic curves play a natural and important role in elliptic cohomology. In earlier work with I. Kriz, thes elliptic curves were interpreted physically in two ways: as corresponding to the intersection of M2 and M5 in the context of (the reduction of M-theory to) type IIA and as the elliptic fiber leading to F-theory for type IIB. In this paper we elaborate

  97. Y. C. Zou, Z. G. Dai, D. Xu

    By considering synchrotron radiative process in the internal shock model and assuming that all internal shocks are nearly equally energetic, we analyze the gamma-ray burst (GRB) emission at different radii corresponding to different observed times. We apply this model to GRB 050904 and find that our analytical results can provide a natural explanation for th

  98. Raphael Bousso, Ben Freivogel

    We consider the question of asymptotic observables in cosmology. We assume that string theory contains a landscape of vacua, and that metastable de Sitter regions can decay to zero cosmological constant by bubble nucleation. The asymptotic properties of the corresponding bounce solution should be incorporated in a nonperturbative quantum theory of cosmology.

  99. James Conant, Jacob Mostovoy, Ted Stanford

    We study generalizations of finite-type knot invariants obtained by replacing the crossing change in the Vassiliev skein relation by some other local move, analyzing in detail the band-pass and doubled-delta moves. Using braid-theoretic techniques, we show that, for a large class of local moves, generalized Goussarov's n-equivalence classes of knots form gro

  100. Prashant

    The paper is taken out.