Skip to content

January 2004 arXiv papers — page 11

Showing 1,001–1,100 of 3,112 papers

  1. Roberto Zucchini

    Recently, Witten showed that there is a natural action of the group SL(2,Z) on the space of 3 dimensional conformal field theories with U(1) global symmetry and a chosen coupling of the symmetry current to a background gauge field on a 3-fold N. He further argued that, for a class of conformal field theories, in the nearly Gaussian limit, this SL(2,Z) action

  2. Qing-Hong Cao, C. -P. Yuan

    A precise determination of the $W$ boson mass at the CERN LHC requires a theoretical calculation in which the effect of the initial-state multiple soft-gluon emission and the final-state photonic correction are simultaneously included. Here, we present such a calculation and discuss its prediction on a few most relevant distributions of the decay leptons.

  3. Hyung Do Kim, Stuart Raby, Leslie Schradin

    Recent precise measurements of sin 2 beta from the B-factories (BABAR and BELLE) and a better known strange quark mass from lattice QCD make precision tests of predictive texture models possible. The models tested include those hierarchical N-zero textures classified by Ramond, Roberts and Ross, as well as any other hierarchical matrix Ansatz with non-zero 1

  4. Sang Pyo Kim

    We apply the canonical quantum field theory based on the Liouville-von Neumann equation to the nonequilibrium linear sigma model. Particular emphasis is put on the mechanism for domain growth of disoriented chiral condensates due to long wavelength modes and its scaling behavior. Scattering effects, decoherence and emergence of order parameter are also discu

  5. Peter Minkowski, Wolfgang Ochs

    The existence of glueballs is predicted in QCD, the lightest one with quantum numbers J^{PC}=0^{++}, but different calculations do not well agree on its mass in the range below 1800 MeV. Several theoretical schemes have been proposed to cope with the experimental data which often have considerable uncertainties. Further experimental studies of the scalar mes

  6. B. Gruter, R. Alkofer, A. Maas, J. Wambach

    We investigate the behaviour of the gluon and ghost propagators, especially their infrared properties, at non-vanishing temperatures. To this end we solve their Dyson-Schwinger equations on a torus and find an infrared enhanced ghost propagator and an infrared vanishing gluon propagator.

  7. Michail P. Rekalo, Egle Tomasi-Gustafsson

    We present two possibilities to determine the P-parity of the pentaquark $Θ^+$, in a model independent way, via the measurement of polarization observables in $p+p\to Θ^+ +Σ^+$, or $n+p\to Θ^+ +Λ^0$, in the near threshold region. Besides the measurement of the spin correlation coefficient, $A_{xx}=A_{yy}$, (in collisions of transversally polarized nucleons),

  8. V. I. Kuvshinov, V. A. Shaparau

    At the non-perturbative stage of jet evolution, fluctuations of collinear gluons are less than those for coherent states that is indication of gluon squeezed states. We show that gluon entangled states which are closely related with two-mode squeezed states of gluon fields can appear by analogy with corresponding photon states in quantum optics.

  9. Giacomo Cacciapaglia, Csaba Csaki, Christophe Grojean, John Terning

    We calculate the tree-level oblique corrections to electroweak precision observables generated in higgless models of electroweak symmetry breaking with a 5D SU(2)_L x SU(2)_R x U(1)_{B-L} gauge group on a warped background. In the absence of brane induced kinetic terms (and equal left and right gauge couplings) we find the S parameter to be ~1.15, while T,U~

  10. Pedro Miguel Martins Ferreira

    We argue that recent results from two-photon processes at LEP are better explained by quarks possessing integer electric charges.

  11. J. M. Zanotti, S. Boinepalli, D. B. Leinweber, A. G. Williams

    The Fat-Link Irrelevant Clover (FLIC) fermion action provides a new form of nonperturbative O(a) improvement and allows efficient access to the light quark-mass regime. FLIC fermions enable the construction of the nonperturbatively O(a)-improved conserved vector current without the difficulties associated with the fine tuning of the improvement coefficients.

  12. Tim Christiansen

    Using approximately 41 pb^-1 of proton-antiproton collisions, recorded with the D0 detector during the TeVatron Run II, this document describes the search for minimal GMSB SUSY signal (with a neutralino as next-to-lightest supersymmetric particle) in di-photon + missing E_T events. Since no deviation from the Standard Model is observed, a 95% confidence leve

  13. Angelo Tartaglia, Matteo Luca Ruggiero

    The asymmetry in the time delay for light rays propagating on opposite sides of a spinning body is analyzed. A frequency shift in the perceived signals is found. A practical procedure is proposed for evidencing the asymmetry, allowing for a measurement of the specific angular momentum of the rotating mass. Orders of magnitude are discussed.

  14. Banibrata Mukhopadhyay, Naresh Dadhich

    We study the scalar and spinor perturbation to Kerr-NUT space-time, that is, Klein-Gordan and Dirac equation therein. The equations are invariant under duality transformation between the gravitational electric (M) and magnetic (l) charge, radial and angular coordinate, and radial and angular component of the field. We solve the equations separating into radi

  15. E. I. Bolotin, G. Sh. Tsitsiashvili, I. V. Golycheva

    A method of temporal factor prognosis of TE (tick-borne encephalitis) infection has been developed. The high precision of the prognosis results for a number of geographical regions of Primorsky Krai has been achieved. The method can be applied not only to epidemiological research but also to others.

  16. D. Vaknin, J. L. Zarestky, J. -P. Rivera, H. Schmid

    Neutron scattering studies of single-crystal LiNiPO$_4$ reveal a spontaneous first-order commensurate-incommensurate magnetic phase transition. Short- and long-range incommensurate phases are intermediate between the high temperature paramagnetic and the low temperature antiferromagnetic phases. The modulated structure has a predominant antiferromagnetic com

  17. Guangyong Xu, P. M. Gehring, V. J. Ghosh, G. Shirane

    We present a new technique which brings a substantial increase of the wave-vector $q$-resolution of triple-axis-spectrometers by matching the measurement wave-vector $q$ to the reflection $τ_a$ of a perfect crystal analyzer. A relative Bragg width of $δ/Q \sim 10^{-4}$ can be achieved with reasonable collimation settings. This technique is very useful in mea

  18. Guangyong Xu, H. Hiraka, K. Ohwada, G. Shirane

    We performed x-ray diffraction studies on a series of (1-$x$)Pb(Zn$_{1/3}$Nb$_{2/3}$)O$_3$-$x$PbTiO$_3$ (PZN-$x$PT) single crystals with different incident photon energies, and therefore different penetration depths. Our results show that outer-layers of $\sim 10$ to 50 $μ$m thick are present in all samples. The structure of those outer-layers is different f

  19. D. A. Stariolo, J. J. Arenzon, G. Fabricius

    A comparative study of the dynamics of inherent structures at low temperatures is performed on different models of glass formers: a three dimensional Lennard-Jones binary mixture (LJBM), facilitated spin models (either symmetrically constrained, SCIC, or asymmetrically, ACIC) and the trap model. We use suitable correlation functions introduced in a previous

  20. Thomas Petermann, Paolo De Los Rios

    The spreading of an epidemic is determined by the connectiviy patterns which underlie the population. While it has been noted that a virus spreads more easily on a network in which global distances are small, it remains a great challenge to find approaches that unravel the precise role of local interconnectedness. Such topological properties enter very natur

  21. G. Giusiano, F. P. Mancini, P. Sodano, A. Trombettoni

    We argue that Josephson junction networks may be engineered to allow for the emergence of new and robust quantum coherent states. We provide a rather intuitive argument showing how the change in topology may affect the quantum properties of a bosonic particle hopping on a network. As a paradigmatic example, we analyze in detail the quantum and thermodynamic

  22. V. P. Gnezdilov, Yu. G. Pashkevich, A. V. Yeremenko, P. Lemmens

    The Raman-active phonons in perovskite-like LaMn1-xCoxO3 (x = 0, 0.2, 0.3, 0.4, and 1.0) were studied by measuring Raman spectra at temperatures of 295 and 5 K. The changes in the spectra with Co doping are correlated with the decrease of orthorhombic distortions. Surprisingly more phonon lines than allowed for the rhombohedral LaCoO3 structure were observed

  23. Emmanuel Clouet, Juan-Miguel Sanchez, Christophe Sigli

    The experimental solubility limit of Zr in Al is well-known. Al3Zr has a stable structure DO23 and a metastable one L12. Consequently there is a metastable solubility limit for which only few experimental data are available. The purpose of this study is to obtain by ab-initio calculations the solubility limit of Zr in Al for the stable as well as the metasta

  24. David Jacob, Bernhard Wunsch, Daniela Pfannkuche

    Charge localization seems unlikely to occur in two vertically coupled symmetric quantum dots even if a small bias voltage breaks the exact isospin-symmetry of the system. However for a three-electron double quantum dot we find a strong localization of charges at certain vertically applied magnetic fields. The charge localization is directly connected to new

  25. Enrico Perfetto, Michele Cini

    We discuss a many-electron Hamiltonian with Hubbard-like repulsive interaction and linear coupling to the phonon branches, having the Cu-O plane of the superconducting cuprates as a paradigm. A canonical transformation extracts an effective two-body problem from the many-body theory. As a prototype system we study the $\cu$ cluster, which yields electronic p

  26. I. Saika-Voivod, F. Sciortino

    We perform extensive simulations of a binary mixture Lennard-Jones system subjected to a temperature jump in order to study the time evolution of fluctuations during aging. Analyzing data from 1500 different aging realizations, we calculate distributions of inherent structure energies for different aging times and contrast them with equilibrium. We find that

  27. Enzo Granato, S. C. Ying

    We study the response of an adsorbed monolayer on a disordered substrate under a driving force using Brownian molecular-dynamics simulation. We find that the sharp longitudinal and transverse depinning transitions with hysteresis still persist in the presence of weak disorder. However, the transitions are smeared out in the strong disorder limit. The theoret

  28. D. Noujni, S. Kamba, A. Pashkin, V. Bovtun

    The microwave, near-millimetre and infrared (IR) dielectric response of Srn+1TinO3n+1 (n=1-4) Ruddlesden-Popper homologous series was studied in the temperature range 10 to 300 K. Remarkable softening of the polar optical mode was observed in Sr4Ti3O10 and Sr5Ti4O13 which explains the increase in microwave permittivity and dielectric loss upon cooling. Howev

  29. D. Valenti, A. Fiasconaro, B. Spagnolo

    We analyze the spatio-temporal patterns of two competing species in the presence of two white noise sources: an additive noise acting on the interaction parameter and a multiplicative noise which affects directly the dynamics of the species densities. We use a coupled map lattice (CML) with uniform initial conditions. We find a nonmonotonic behavior both of

  30. Anton Bovier, Jiri Cerny, Ostap Hryniv

    We propose a class of Markovian agent based models for the time evolution of a share price in an interactive market. The models rely on a microscopic description of a market of buyers and sellers who change their opinion about the stock value in a stochastic way. The actual price is determined in realistic way by matching (clearing) offers until no further t

  31. D. S. Dean, A. Lefèvre

    The behavior of the self diffusion constant of Langevin particles interacting via a pairwise interaction is considered. The diffusion constant is calculated approximately within a perturbation theory in the potential strength about the bare diffusion constant. It is shown how this expansion leads to a systematic double expansion in the inverse temperature $β

  32. Stanislas Rohart, Gregory Baudot, Vincent Repain, Yann Girard

    Hetero-epitaxial growth on a strain-relief vicinal patterned substrate has revealed unprecedented 2D long range ordered growth of uniform cobalt nanostructures. The morphology of a Co sub-monolayer deposit on a Au(111) reconstructed vicinal surface is analyzed by Variable Temperature Scanning Tunneling Microscopy (VT-STM) experiments. A rectangular array of

  33. B. Basu, P. Bandyopadhyay

    It is shown that the deviation of fractional quantum Hall edge fluid from power law correlation functions with universal exponent $α=1/ν$ as observed in recent experiment may be explained when analyzed from the viewpoint of chiral anomaly and Berry phase. It is observed that at the edge anomaly vanishes and this induces a nonlocal effect in the construction

  34. C. Berthod

    The origin of the vortex-core states in s-wave and d_{x^2-y^2}-wave superconductors is investigated by means of some selected numerical experiments. By relaxing the self-consistency condition in the Bogoliubov-de Gennes equations and tuning the order parameter in the core region, it is shown that the suppression of the superfluid density in the core is not a

  35. H. Kotegawa, Y. Tokunaga, Y. Araki, G. -q. Zheng

    We report a coexistence of superconductivity and antiferromagnetism in five-layered compound HgBa$_2$Ca$_4$Cu$_5$O$_y$ (Hg-1245) with $T_c=108$ K, which is composed of two types of CuO$_2$ planes in a unit cell; three inner planes (IP's) and two outer planes (OP's). The Cu-NMR study has revealed that the optimallydoped OP undergoes a superconducting

  36. J. Deisenhofer, H. -A. Krug von Nidda, A. Loidl, K. Ahn

    The spin dynamics of GdI_2 have been investigated by ESR spectroscopy. The temperature dependences of the resonance field and ESR intensity are well described by the model for the spin susceptibility proposed by Eremin et al. [Phys. Rev. B 64, 064425 (2001)]. The temperature dependence of the resonance linewidth shows a maximum similar to the electrical resi

  37. Ratnadeep Roy, Purusattam Ray

    We study the dynamics of spin flipping at first order transitions in zero temperature two-dimensional random-field Ising model driven by an external field. We find a critical value of the disorder strength at which a discontinuous sharp jump in magnetization first occurs. We discuss growth morphology of the flipped-spin domains at and away from criticality.

  38. Koichi Watanabe, Takafumi Kita

    We study nonmagnetic impurity effects in MgB$_{2}$ using the quasiclassical equations of superconductivity for a weak-coupling two-band model. Parameters in the model are fixed so as to reproduce experiments on MgB$_{2}$ as closely as possible. The quasiparticle density of states and the specific heat are calculated for various values of the interband impuri

  39. M. Xu, W. Cai, M. Lax, R. R. Alfano

    Light propagation in an infinite uniform turbid medium is treated as a Markov stochastic process of photons to provide an intuitive framework for photon migration. The macroscopic physical quantities of photon migration are shown to be completely determined by the microscopic statistics of the photon propagation direction in direction space and a generalized

  40. Ruben Costa-Santos

    We discuss a geometrical interpretation of the Z-invariant Ising model in terms of isoradial embeddings of planar lattices. The Z-invariant Ising model can be defined on an arbitrary planar lattice if and only if certain paths on the lattice edges do not intersect each other more than once or self-intersect. This topological constraint is equivalent to the e

  41. B. Basu, S. Dhar, P. Bandyopadhyay

    It is here pointed out that the antiferromagnetic spin fluctuation may be associated with a gauge field which gives rise to the antiferromagnetic ground state chirality. This is associated with the chiral anomaly and Berry phase when we consider the two dimensional spin system on the surface of a 3D sphere with a monopole at the centre. This realizes the RVB

  42. Rene Plume, Michael J. Kaufman, David A. Neufeld, Ronald L. Snell

    We have observed 6 clouds along the line-of-sight toward W49A using the Submillimeter Wave Astronomy Satellite (SWAS) and several ground-based observatories. The ortho-H2O 1-0 and OH (1665 and 1667 MHz) transitions are observed in absorption, whereas the low-J CO, 13CO, and C18O lines, as well as the [CI] 1-0 transition, are seen in emission. By using both t

  43. Richard V. E. Lovelace, Marina M. Romanova

    A model is developed for relativistic Poynting jets from the inner region of a disk around a rotating black hole. The disk is initially threaded by a dipole-like magnetic field. The model is derived from the special relativistic equation for a force-free electromagnetic field. The ``head'' of the Poynting jet is found to propagate outward with a velo

  44. F. Miniati

    The contribution to the ultraviolet background (UVB) from thermal emission due to gas shock heated during cosmic structure formation is assessed with an updated version of Press-Schechter (Sheth & Tormen 1999) formalism. The calculation is consistent with empirical estimates based on the observed properties of galaxies and the observed cosmic star formation

  45. P. Schuller, P. Salomé, G. Perrin, B. Mennesson

    Recently available near-infrared interferometric data on late-type stars show a strong increase of diameter for asymptotic giant branch (AGB) stars between the K (2.0 - 2.4 μm) and L (3.4 - 4.1 μm) bands. Aiming at an explanation of these findings, we chose the objects αOrionis (Betelgeuse), SW Virginis, and R Leonis, which are of different spectral types an

  46. F. Miniati

    I present a review of nonthermal processes in the large scale structure of the universe. After examining the properties of cosmological shock waves and their role as particle accelerators, I discuss the main observational facts, from radio to \gr and describe the processes that are thought be responsible for the observed nonthermal emissions. Finally, I emph

  47. M. E. Putman, C. Thom, B. K. Gibson, L. Staveley-Smith

    A possible gaseous component to the stream of debris from the Sagittarius dwarf galaxy is presented. We identify 4 - 10 x 10^6 Msun of neutral hydrogen along the orbit of the Sgr dwarf in the direction of the Galactic anticenter (at 36 kpc, the distance to the stellar debris in this region). This is 1-2% of the estimated total mass of the Sgr dwarf. Both the

  48. Suzanne Talon, Corinne Charbonnel

    This paper is the second in a series where we examine the generation and filtering of internal gravity waves in stars and the consequences of wave induced transport of angular momentum at various stages of the stellar evolution. Here we concentrate on Pop II dwarf stars and we focus in particular on the differential properties of internal gravity waves as a

  49. John P. Hughes, Ian Dell'Antonio, Joseph Hennawi, Vera Margoniner

    We report on preliminary results of our X-ray survey of the most massive clusters currently identified from the Deep Lens Survey (DLS). The DLS cluster sample is selected based on weak lensing shear, which makes it possible for the first time to study clusters in a baryon-independent way. In this article we present X-ray properties of a subset of the shear-s

  50. John P. Hughes, Robert B. Friedman, Patrick Slane, Sangwook Park

    We report the discovery of pulsed X-ray emission from the compact object CXOU J112439.1-591620 within the Galactic supernova remnant G292.0+1.8 using the High Resolution Camera on the Chandra X-Ray Observatory. The X-ray period is consistent with the extrapolation of the radio period and spindown rate of PSR J1124-5916. The X-ray pulse is single peaked and b

  51. Gianfranco De Zotti, Gian Luigi Granato, Laura Silva, Luigi Danese

    The mutual feedback between star formation and nuclear activity in large spheroidal galaxies may be a key ingredient to overcome several difficulties plaguing current semi-analytic models for galaxy formation. We discuss some observational implications of the model by Granato et al. (2003) for the co-evolution of galaxies and active nuclei at their centers a

  52. K. Dolag, M. Jubelgas, V. Springel, S. Borgani

    We study the formation of clusters of galaxies using high-resolution hydrodynamic cosmological simulations that include the effect of thermal conduction with an effective isotropic conductivity of 1/3 the classical Spitzer value. We find that, both for a hot ($T_{\rm ew}\simeq 12$ keV) and several cold ($T_{\rm ew}\simeq 2$ keV) galaxy clusters, the baryonic

  53. Jacob Biemond

    Many authors have considered a gravitational origin of the magnetic field of celestial bodies. Especially, the so-called Wilson-Blackett formula has been investigated, both theoretically and observationally. It appeared possible to deduce this formula from general relativity, e. g., by application of a special interpretation of gravito-magnetic theory. More

  54. H. Uitenbroek, E. Miller-Ricci, A. Asensio Ramos, J. Trujillo Bueno

    We investigate the possibility of measuring magnetic field strength in G-band bright points through the analysis of Zeeman polarization in molecular CH lines. To this end we solve the equations of polarized radiative transfer in the G band through a standard plane-parallel model of the solar atmosphere with an imposed magnetic field, and through a more reali

  55. K. A. Postnov, A. M. Cherepashchuk

    We analyze the mass distribution of stellar black holes derived from the light and radial velocity curves of optical stars in close binary systems using dynamical methods. The systematic errors inherent in this approach are discussed. These are associated primarily with uncertainties in models for the contribution from gaseous structures to the optical brigh

  56. Tod E. Strohmayer

    Observations with NASA's Rossi X-ray Timing Explorer (RXTE) have resulted in the discovery of fast (200 - 600 Hz), coherent X-ray intensity oscillations (hereafter, "burst oscillations") during thermonuclear X-ray bursts from 12 low mass X-ray binaries (LMXBs). It is now beyond doubt that these oscillations result from spin modulation of the ther

  57. Marek A. Abramowicz, Wlodek Kluzniak, Zdenek Stuchlik, Gabriel Torok

    Many Galactic black hole and neutron star sources in low X-ray mass binaries show QPOs (quasi periodic oscillations) in their observed X-ray fluxes, i.e. peaks in the Fourier variability power spectra. Pairs of twin peaks are observed, and in black-hole systems their frequencies (upp), (down) are in rational ratios. For example, in all four microquasars with

  58. H. -Th. Janka, R. Buras, K. Kifonidis, A. Marek

    Recent progress in modeling core-collapse supernovae is summarized and set in perspective. Two-dimensional simulations with state-of-the-art treatment of neutrino transport still fail to produce powerful explosions, but evidence is presented that they are very close to success.

  59. L. van Zyl, B. Warner, D. O'Donoghue, C. Hellier

    The dwarf nova GW Librae is the first cataclysmic variable discovered to have a primary in a white dwarf instability strip, making it the first multi-mode, nonradially-pulsating star known to be accreting. The primaries of CVs, embedded in hot, bright accretion discs, are difficult to study directly. Applying the techniques of asteroseismology to GW Librae c

  60. T. G. Müller, J. A. D. L. Blommaert

    We investigated the physical and thermal properties of 65 Cybele}, one of the largest main-belt asteroids. Based on published and recently obtained thermal infrared observations, including ISO measurements, we derived through thermophysical modelling (TPM) a size of 302x290x232 km (+/- 4 %) and an geometric visible albedo of 0.050+/-0.005. Our model of a reg

  61. M. Sol Alonso, Patricia B. Tissera, Georgina Coldwell, Diego G. Lambas

    We analyse the effects of galaxy interactions on star formation in groups and clusters of galaxies with virial masses in the range $10^{13} - 10 ^{15} M_{\odot}$. We find a trend for galaxy-galaxy interactions to be less efficient in triggering star formation in high density regions in comparison with galaxies with no close companion. However, we obtain the

  62. A. W. McConnachie, M. J. Irwin, A. M. N. Ferguson, R. A. Ibata

    The absolute bolometric luminosity of the point of core Helium ignition in old, metal poor, red-giant stars is of roughly constant magnitude, varying only very slightly with mass or metallicity. It can thus be used as a standard candle. Here, we review the main difficulties in measuring this location in any real dataset and develop an empirical approach to o

  63. A. G. Kuranov, K. A. Postnov

    The population synthesis method is used to study the possibility of explaining the appreciable fraction (20^+12_15%) of the intergalactic (no-host) type Ia supernovae observed in galaxy clusters (Gal-Yam ete al. 2003) by binary whote dwarf merginngs in the cores of globular clusters. In a typical globular cluster, the number of merging double white dwarfs is

  64. Alessia Gualandris, Simon Portegies Zwart, Peter P. Eggleton

    We study the dynamical interaction in which the two single runaway stars AE Aurigae and mu Columbae and the binary iota Orionis acquired their unusually high space velocity. The two single runaways move in almost opposite directions with a velocity greater than 100 km/s away from the Trapezium cluster. The star iota Ori is an eccentric (e=0.8) binary moving

  65. M. S. Bessell, N. Christlieb, B. Gustafsson

    We have determined the oxygen abundance of HE0107-5240 from UV-OH lines detected in VLT/UVES spectra. Using a plane-parallel LTE model atmosphere, we derive [O/Fe] = +2.4, and a similar analysis of CD -38 245 yields [O/Fe] = +1.0. We estimate systematic errors due to 3D effects to be in the order of 0.3 to 0.4 dex. That is, our derived O abundances are likel

  66. Hubert Klahr

    This paper contains a local linear stability analysis for accretion disks under the influence of a global radial entropy gradient beta = - d log T / d log r for constant surface density. Numerical simulations suggested the existence of an instability in two- and three-dimensional models of the solar nebula. The present paper tries to clarify, quantify, and e

  67. S. M. Crawford, M. A. Bershady, A. D. Glenn, J. G. Hoessel

    Luminous Compact Blue Galaxies (LCBGs) are a heterogeneous class which dominate an intermediate phase of galaxy evolution. These sources account for the majority of the star formation between 0.3<z<1, yet the identity of their present-day counterparts is an open question. An environmental dependence to their evolution may provide the answer. We have undertak

  68. H. B. Richer, J. Brewer, G. G. Fahlman, J. Kalirai

    We respond to the paper by De Marchi, Paresce, Straniero and Moroni (2003) on the white dwarf cooling age of M4. The authors question the data analysis and interpretation that led to the conclusions in Hansen et al. (2002). In their paper, De Marchi et al. are unable to obtain photometry as deep as ours from the same data set and therefore assert that only a

  69. J A Sellwood

    Newtonian mechanics indicates that galaxies and galaxy clusters are much more massive than we would have guessed from their luminosities, with the discrepancy being generally attributed to dark matter halos. An alternative hypothesis is that accelerations in very weak gravitational fields are larger than predicted by Newton&#39;s laws, and there is no need f

  70. B. C. Kelly, T. A. McKay

    We describe the application of the `shapelet' linear decomposition of galaxy images to multi-wavelength morphological classification using the $u,g,r,i,$ and $z$-band images of 1519 galaxies from the Sloan Digital Sky Survey. We utilize elliptical shapelets to remove to first-order the effect of inclination on morphology. After decomposing the galaxies we pe

  71. M. D. Girardeau, M. Olshanii

    Divergence-free pseudopotentials for spatially even and odd-wave interactions in spinor Fermi gases in tight atom waveguides are derived. The Fermi-Bose mapping method is used to relate the effectively one-dimensional fermionic many-body problem to that of a spinor Bose gas. Depending on the relative magnitudes of the even and odd-wave interactions, the N-at

  72. Pablo Minces

    We consider a scalar field theory on AdS, and show that the usual AdS/CFT prescription is unable to map to the boundary a part of the information arising from the quantization in the bulk. We propose a solution to this problem by defining the energy of the theory in the bulk through the Noether current corresponding to time displacements, and, in addition, b

  73. Nicholas R. Howe, Alexandra Deschamps

    For many tracking and surveillance applications, background subtraction provides an effective means of segmenting objects moving in front of a static background. Researchers have traditionally used combinations of morphological operations to remove the noise inherent in the background-subtracted result. Such techniques can effectively isolate foreground obje

  74. J. D. Franson, B. C. Jacobs, T. B. Pittman

    We show that the quantum Zeno effect can be used to implement several quantum logic gates for photonic qubits, including a gate that is similar to the square-root of SWAP operation. The operation of these devices depends on the fact that photons can behave as if they were non-interacting fermions instead of bosons in the presence of a strong Zeno effect. The

  75. BRAHMS Collaboration, I. Arsene

    Charged-particle pseudorapidity densities are presented for the d+Au reaction at sqrt{s_{NN}}=200 GeV with -4.2 <= eta <= 4.2$. The results, from the BRAHMS experiment at RHIC, are shown for minimum-bias events and 0-30%, 30-60%, and 60-80% centrality classes. Models incorporating both soft physics and hard, perturbative QCD-based scattering physics agree we

  76. Christian Saemann, Martin Wolf

    It has been known for quite some time that the N=4 super Yang-Mills equations defined on four-dimensional Euclidean space are equivalent to certain constraint equations on the Euclidean superspace R^(4|16). In this paper we consider the constraint equations on a deformed superspace R^(4|16)_\hbar a la Seiberg and derive the deformed super Yang-Mills equation

  77. Ralph Blumenhagen, Timo Weigand

    We explicitly construct A-type orientifolds of supersymmetric Gepner models. In order to reduce the tadpole cancellation conditions to a treatable number we explicitly work out the generic form of the one-loop Klein bottle, annulus and Moebius strip amplitudes for simple current extensions of Gepner models. Equipped with these formulas, we discuss two exampl

  78. Matthias Burkardt

    The $t$-dependence of generalized parton distrbutions for $x\to 1$ is discussed. We argue that constituent quark models, where the $t$-dependence for $x\to 1$ is through the product $(1-x)t$, are inconsistent. Instead we suggest a leading dependence in terms of $(1-x)^n t$, where $n\geq 2$, for $x\to 1$.

  79. Florian Meier, Veronica Cerletti, Oliver Gywat, Daniel Loss

    Time-resolved Faraday rotation has recently demonstrated coherent transfer of electron spin between quantum dots coupled by conjugated molecules. Using a transfer Hamiltonian ansatz for the coupled quantum dots, we calculate the Faraday rotation signal as a function of the probe frequency in a pump-probe setup using neutral quantum dots. Additionally, we stu

  80. V. M. Pudalov, M. E. Gershenson, H. Kojima

    In this paper, we analyze several experiments that address the effects of electron-electron interactions in 2D electron (hole) systems in the regime of low carrier density. The interaction effects result in renormalization of the effective spin susceptibility, effective mass, and g*-factor. We found a good agreement among the data obtained for different 2D e

  81. C. Schaefer, R. Speith, M. Hipp, W. Kley

    We have performed Smoothed Particle Hydrodynamics (SPH) simulations to study the time evolution of one and two protoplanets embedded in a protoplanetary accretion disc. We investigate accretion and migration rates of a single protoplanet depending on several parameters of the protoplanetary disc, mainly viscosity and scale height. Additionally, we consider t

  82. S. Lubeck, R. D. Willmann

    In this work we consider the steady state scaling behavior of directed percolation around the upper critical dimension. In particular we determine numerically the order parameter, its fluctuations as well as the susceptibility as a function of the control parameter and the conjugated field. Additionally to the universal scaling functions, several universal a

  83. Sandra Barsky, Rafael Delgado-Buscalioni, Peter Coveney

    We compare a newly developed hybrid simulation method which combines classical molecular dynamics (MD) and computational fluid dynamics (CFD) to a simulation consisting only of molecular dynamics. The hybrid code is composed of three regions: a classical MD region, a continuum domain where the dynamical equations are solved by standard CFD methods, and an ov

  84. J. A. Nieto, M. P. Ryan, O. Velarde, C. M. Yee

    It is shown that, with the only exception of $n=2$, the Einstein-Hilbert action in $n+D+d$ dimensions, with $n$ times, is invariant under the duality transformation $a\to \frac{1}{a}$ and $b\to \frac{1}{b}$, where $a$ is a Friedmann-Robertson-Walker scale factor in $D$ dimensions and $b$ a Brans-Dicke scalar field in $d$ dimensions respectively. We investiga

  85. Y. Meurice, M. B. Oktay

    We study numerically the continuum limit corresponding to the non-trivial fixed point of Dyson&#39;s hierarchical model. We discuss the possibility of using the critical amplitudes as input parameters. We determine numerically the leading and subleading critical amplitudes of the zero-momentum $2l$-point functions in the symmetric phase up to l=10 for random

  86. Hoshang Heydari, Gunnar Björk

    We propose an explicit formula for an entanglement measure of pure multipartite quantum states, then study a general pure tripartite state in detail, and at end we give some simple but illustrative examples on four-qubits and m-qubits states.

  87. Hoshang Heydari, Gunnar Björk

    We propose a entanglement measure for pure $M \otimes N$ bipartite quantum states. We obtain the measure by generalizing the equivalent measure for a $2 \otimes 2$ system, via a $2 \otimes 3$ system, to the general bipartite case. The measure emphasizes the role Bell states have, both for forming the measure, and for experimentally measuring the entanglement

  88. A. D. Armour

    The current noise spectrum of a single-electron transistor (SET) coupled to a nano-mechanical resonator is calculated in the classical regime. Correlations between the charge on the SET island and the position of the resonator give rise to a distinctive noise spectrum which can be very different from that of the uncoupled SET. The current noise spectrum of t

  89. Ari Brynjolfsson

    A new interaction, plasma redshift, is derived, which is important only when photons penetrate a hot, sparse electron plasma. The derivation of plasma redshift is based entirely on conventional axioms of physics. When photons penetrate a cold and dense plasma, they lose energy through ionization and excitation, Compton scattering on the individual electrons,

  90. Stuart Raby

    In this article we try to clarify why supersymmetry [SUSY] and supersymmetric grand unified theories [SUSY GUTs] are the new standard model of particle physics, i.e. the standard by which all other theories and experiments are measured.

  91. Cedric Simenel, Philippe Chomaz, Gilles De France

    Classical mechanics and Time Dependent Hartree-Fock (TDHF) calculations of heavy ions collisions are performed to study the rotation of a deformed nucleus in the Coulomb field of its partner. This reorientation is shown to be independent on charges and relative energy of the partners. It only depends upon the deformations and inertias. TDHF calculations pred

  92. R. A. Blythe, W. Janke, D. A. Johnston, R. Kenna

    The one-dimensional Asymmetric Exclusion Process (ASEP) is a paradigm for nonequilibrium dynamics, in particular driven diffusive processes. It is usually considered in a canonical ensemble in which the number of sites is fixed. We observe that the grand-canonical partition function for the ASEP is remarkably simple. It allows a simple direct derivation of t

  93. M. Coraddu, M. Lissia, G. Mezzorani, Yu. V. Petrushevich

    The Bochum experimental enhancement of the d+d fusion rate in a deuterated metal matrix at low incident energies is explained by the quantum broadening of the momentum-energy dispersion relation and consequent modification of the high-momentum tail of the distribution function from an exponential to a power-law.

  94. Aristophanes Dimakis, Folkert Muller-Hoissen

    A linear system, which generates a Moyal-deformed two-dimensional soliton equation as integrability condition, can be extended to a three-dimensional linear system, treating the deformation parameter as an additional coordinate. The supplementary integrability conditions result in a first order differential equation with respect to the deformation parameter,

  95. Ryusuke Ikeda, Hiroto Adachi

    The mean field vortex phase diagram of a quasi two dimensional superconductor with a nodal d-wave pairing and with strong Pauli spin depairing is examined in the parallel field case in order to examine an effect of gap nodes (or minima) on the stability of a FFLO-like vortex lattice. We find through a heuristic argument and a model calculation with a four-fo

  96. J. D. Vergados, H. Ejiri

    In this paper we estimate the event rates of neutralino-nucleus scattering leading to electron emission by the atomic ionization. We find that the branching ratio for detecting electrons vis a vis the traditional neutralino nucleus elastic scattering sensitively depends on the threshold energy. In the case of a light target and a neutralino mass of 100 GeV w

  97. Donghi Lee

    Let u be a cyclic word in a free group F_n of finite rank n that has the minimum length over all cyclic words in its automorphic orbit, and let N(u) be the cardinality of the set {v: |v|=|u| and v=ϕ(u) for some ϕ\in AutF_n}. In this paper, we prove that N(u) is bounded by a polynomial function of degree 2n-3 with respect to |u| under the hypothesis that if t

  98. Richard Corrado, Nick Halmagyi

    Deformation of N=2 quiver gauge theories by adjoint masses leads to fixed manifolds of N=1 superconformal field theories. We elaborate on the role of the complex three-form flux in the IIB duals to these fixed point theories, primarily using field theory techniques. We study the moduli space at a fixed point and find that it is either the two (complex) dimen

  99. H. Ollivier, J. -P. Tillich

    We describe the theory of quantum convolutional error correcting codes. These codes are aimed at protecting a flow of quantum information over long distance communication. They are largely inspired by their classical analogs which are used in similar circumstances in classical communication. In this article, we provide an efficient polynomial formalism for d

  100. Artur Scherer, Andrei N. Soklakov, Ruediger Schack

    Within the decoherent histories formulation of quantum mechanics, we investigate necessary conditions for decoherence of arbitrarily long histories. We prove that fine-grained histories of arbitrary length decohere for all classical initial states if and only if the unitary evolution preserves classicality of states (using a natural formal definition of clas