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December 2008 arXiv papers — page 24

Showing 2,3012,400 of 5,096 papers

  1. Paata Kakashvili, C. J. Bolech

    A growing expertise to engineer, manipulate and probe different cold-atom analogs of electronic condensed matter systems allows to probe properties of exotic pairing. We study paired states of spin-imbalanced ultracold atomic system of fermions with attractive short-range interactions in one-dimensional traps. Calculations are done using the Bethe Ansatz tec

  2. R. R. Gal, P. A. A. Lopes, R. R. de Carvalho, J. L. Kohl-Moreira

    We present the complete galaxy cluster catalog from the Northern Sky Optical Cluster Survey, a new, objectively defined catalog of candidate galaxy clusters at z<0.25 drawn from the Digitized Second Palomar Observatory Sky Survey (DPOSS). The data presented here cover the Southern Galactic Cap, as well as the less-well calibrated regions of the Northern Gala

  3. T. J. Atherton, J. R. Sambles, J. P. Bramble, J. R. Henderson

    We have discovered an optically uniform type of domain that occurs in Twisted Nematic (TN) cells that are constructed from substrates chemically patterned with stripes via microcontact printing of Self-Assembled Monolayers (SAM); such domains do not occur in TN cells constructed from uniform substrates. In such a cell, the azimuthal anchoring at the substrat

  4. A. A. Abdo

    The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed exposure and early sky survey scanning. We have used the Vela signal to verify Fermi timing and angular resolution. The

  5. R. Buta, X. Zhang

    The morphology of a disk galaxy is closely linked to its kinematic state. This is because density wave features are likely made of spontaneously-formed modes which are allowed to arise in the galactic resonant cavity of a particular basic disk state. The pattern speed of a density wave is an important parameter that characterizes the wave and its associated

  6. Alfredo Aranda

    We present two different models with electroweak scale right-handed neutrinos. One of the models is created under the constraint that any addition to the Standard Model must not introduce new higher scales. The model contains right-handed neutrinos with electroweak scale masses and a lepton number violating singlet scalar field. The scalar phenomenology is a

  7. Lei Chang, Yu-xin Liu, Craig D. Roberts, Yuan-mei Shi

    The chiral susceptibility is given by the scalar vacuum polarisation at zero total momentum. This follows directly from the expression for the vacuum quark condensate so long as a nonperturbative symmetry preserving truncation scheme is employed. For QCD in-vacuum the susceptibility can rigorously be defined via a Pauli-Villars regularisation procedure. Owin

  8. Matthew P. A. Fisher, Olexei I. Motrunich, Donna N. Sheng

    Characterizing and accessing quantum phases of itinerant bosons or fermions in two dimensions (2D) that exhibit singular structure along surfaces in momentum space but have no quasi-particle description remains as a central challenge in the field of strongly correlated physics. Fortuitously, signatures of such 2D strongly correlated phases are expected to be

  9. M. Eichenfield, R. Camacho, J. Chan, K. J. Vahala

    We describe the design, fabrication, and measurement of a cavity opto-mechanical system consisting of two nanobeams of silicon nitride in the near-field of each other, forming a so-called &#34;zipper&#34; cavity. A photonic crystal patterning is applied to the nanobeams to localize optical and mechanical energy to the same cubic-micron-scale volume. The picr

  10. Fergal Mullally, William T. Reach, Steven Degennaro, Adam Burrows

    We present infrared observations in search of a planet around the white dwarf, GD66. Time-series photometry of GD66 shows a variation in the arrival time of stellar pulsations consistent with the presence of a planet with mass > 2.4Mj. Any such planet is too close to the star to be resolved, but the planet&#39;s light can be directly detected as an excess fl

  11. Gregory M. Grason

    Molecular chirality frustrates the two-dimensional assembly of filamentous molecules, a fact that reflects the generic impossibility of imposing a global twisting of layered materials. We explore the consequences of this frustration for hexagonally-ordered assemblies of chiral filaments that are {\it finite} in lateral dimension. Specifically, we employ a co

  12. Peter G. Wolynes

    Complex spatiotemporal structures develop during the process of aging glasses after cooling and of rejuvenating glasses upon heating. The key to understanding these structures is the interplay between the activated reconfiguration events which generate mobility and the transport of mobility. These effects are both accounted for by combining the random first

  13. Frank Julicher, Jacques Prost

    We discuss the motion of colloidal particles relative to a two component fluid consisting of solvent and solute. Particle motion can result from (i) net body forces on the particle due to external fields such as gravity; (ii) slip velocities on the particle surface due to surface dissipative phenomena. The perturbations of the hydrodynamic flow field exhibit

  14. Elisabetta Bissaldi, Andreas von Kienlin, Giselher G. Lichti, Helmut Steinle

    One of the scientific objectives of NASA&#39;s Fermi Gamma-ray Space Telescope is the study of Gamma-Ray Bursts (GRBs). The Fermi Gamma-Ray Burst Monitor (GBM) was designed to detect and localize bursts for the Fermi mission. By means of an array of 12 NaI(Tl) (8 keV to 1 MeV) and two BGO (0.2 to 40 MeV) scintillation detectors, GBM extends the energy range

  15. E. Harper-Clark, N. Murray

    We have tested the two main theoretical models of bubbles around massive star clusters, Castor et al. and Chevalier & Clegg, against observations of the well studied Carina Nebula. The Castor et al. theory over-predicts the X-ray luminosity in the Carina bubble by a factor of 60 and expands too rapidly, by a factor of 4; if the correct radius and age are use

  16. N. P. M. Kuin, W. B. Landsman, M. J. Page, P. Schady

    We present the earliest ever ultraviolet spectrum of a gamma-ray burst (GRB) as observed with the Swift-UVOT. The GRB 081203A spectrum was observed for 50 seconds with the UV grism starting 251 seconds after the Swift-BAT trigger when the GRB was of u ~13.4 mag and still rising to its peak optical brightness. The UV grism spectrum shows a damped Ly-alpha lin

  17. Sung Nae Cho

    An optical shutter based on charged particles is presented. The output light intensity of the proposed device has an intrinsic dependence on the interparticle spacing between charged particles, which can be controlled by varying voltages applied to the control electrodes. The interparticle spacing between charged particles can be varied continuously and this

  18. M. Eshaghi Gordji, S. Kaboli, S. Zolfaghari

    In this paper, we obtain the general solution and the generalized Hyers-Ulam Rassias stability of the functional equation $$3(f(x+2y)+f(x-2y))=12(f(x+y)+f(x-y))+4f(3y)-18f(2y)+36f(y)-18f(x).$$

  19. Emilio Porcu, René L. Schilling

    We show that a large subclass of variograms is closed under products and that some desirable stability properties, such as the product of special compositions, can be obtained within the proposed setting. We introduce new classes of kernels of Schoenberg-Lévy type and demonstrate some important properties of rotationally invariant variograms.

  20. Teppei Okumura, Y. P. Jing

    We examine whether the gravitational shear--intrinsic ellipticity (GI) correlation function of the luminous red galaxies (LRGs) can be modeled with the distribution function of a misalignment angle advocated recently by Okumura et al. For this purpose, we have accurately measured the GI correlation for the LRGs in the Data Release 6 (DR6) of the Sloan Digita

  21. E. J. Murphy, R. -R. Chary, D. M. Alexander, M. Dickinson

    (abridged) We present deep Spitzer mid-infrared spectroscopy, along with 16, 24, 70, and 850um photometry, for 22 galaxies located in GOODS-N. The sample spans a redshift range of 0.6 < z < 2.6, 24um flux densities between ~0.2-1.2 mJy, and consists of SMGs, AGN, and optically faint (z_AB > 25) sources. We find that IR luminosities derived by fitting local S

  22. Alexi Morin-Duchesne, Yvan Saint-Aubin

    A Fortuin-Kasteleyn cluster on a torus is said to be of type $\{a,b\}, a,b\in\mathbb Z$, if it possible to draw a curve belonging to the cluster that winds $a$ times around the first cycle of the torus as it winds $-b$ times around the second. Even though the $Q$-Potts models make sense only for $Q$ integers, they can be included into a family of models para

  23. Yu-Zhong Zhang, Hem C. Kandpal, Ingo Opahle, Harald O. Jeschke

    Using {\it ab initio} molecular dynamics we investigate the electronic and lattice structure of $A$Fe$_2$As$_2$ ($A$=Ca, Sr, Ba) under pressure. We find that the structural phase transition (orthorhombic to tetragonal symmetry) is always accompanied by a magnetic phase transition in all the compounds, while the nature of the transitions is different for the

  24. Kirill Koshelev

    Two forms of relativistic density functional are derived from Dirac equation. Based on their structure analysis model of split electron is proposed. In this model electric charge and mass of electron behave like two point-like particles. It is shown that two electrons obeying this model cannot occupy the same quantum state. Empirical verification of the mode

  25. Alan D. Bristow, Denis Karaiskaj, Xingcan Dai, Richard. P. Mirin

    We study the coherent light-matter interactions of GaAs quantum wells associated with excitons, biexcitons and many-body effects. For most polarization configurations, excitonic features dominate the phase-resolved two-dimensional Fourier-transform (2DFT) spectra and have dispersive lineshapes, indicating the presence of many-body interactions. For cross-lin

  26. Andreas H. Pawlik, Joop Schaye

    Photo-heating associated with reionisation and kinetic feedback from core-collapse supernovae have previously been shown to suppress the high-redshift cosmic star formation rate. Here we investigate the interplay between photo-heating and supernova feedback using a set of cosmological, smoothed particle hydrodynamics simulations. We show that photo-heating a

  27. Daniel Podolsky, Hae-Young Kee, Yong Baek Kim

    We show the existence of an emergent SO(6) symmetry in the low energy description of the iron pnictides. This approximate symmetry provides a unifying framework for the occurrence of spin density wave (SDW) and superconductivity (SC) in these materials. We use this symmetry to make several predictions for future experiments, including the topology of the pha

  28. Y. Ali-Haïmoud, C. M. Hirata, C. Dickinson

    We present a comprehensive treatment of the spectrum of electric dipole emission from spinning dust grains, updating the commonly used model of Draine and Lazarian. Grain angular velocity distributions are computed using the Fokker-Planck equation; we revisit the drift and diffusion coefficients for the major torques on the grain, including collisions, grain

  29. M. Storni, R. H. Morf, S. Das Sarma

    Results from exact diagonalization show that the spin-polarized Coulomb ground state at nu=5/2 is adiabatically connected with the Moore-Read wave function for systems with up to Nel = 16 electrons on the surface of a sphere. Varying the Haldane pseudopotentials v1 and v3, keeping all others at their value for Coulomb interaction, energy gap and (v1,v3)-depe

  30. Frank Pollmann, Subroto Mukerjee, Ari Turner, Joel E. Moore

    Studies of entanglement in many-particle systems suggest that most quantum critical ground states have infinitely more entanglement than non-critical states. Standard algorithms for one-dimensional many-particle systems construct model states with limited entanglement, which are a worse approximation to quantum critical states than to others. We give a quant

  31. M. V. Bondarko

    We construct a &#39;triangulated analogue&#39; of coniveau spectral sequences: the motif of a variety over a countable field is &#39;decomposed&#39; (in the sense of Postnikov towers) into the twisted (co)motives of its points; this is generalized to arbitrary Voevodsky&#39;s motives. To this end we construct a &#39;Gersten&#39; weight structure for a certai

  32. Simon Catterall

    We construct a four dimensional Yang-Mills theory with ${\cal N}=4$ twisted supersymmetry whose classical vacua correspond to four dimensional anti-de Sitter space. The theory utilizes a complex gauge field whose real part is a spin connection which is used to enforce local Lorentz invariance. The imaginary part of the connection can then be interpreted as a

  33. Ben Craps, Frederik De Roo, Oleg Evnin

    We study free string propagation in families of plane wave geometries developing strong scale-invariant singularities in certain limits. We relate the singular limit of the evolution for all excited string modes to that of the center-of-mass motion (the latter existing for discrete values of the overall plane wave profile normalization). Requiring that the e

  34. Vesko Valov

    Let $M$ be a complete metric $ANR$-space such that for any metric compactum $K$ the function space $C(K,M)$ contains a dense set of Bing (resp., Krasinkiewicz) maps. It is shown that $M$ has the following property: If $f\colon X\to Y$ is a perfect surjection between metric spaces, then $C(X,M)$ with the source limitation topology contains a dense $G_δ$-subse

  35. Martin Schmaltz, Jesse Thaler

    Any extension of the standard model that aims to describe TeV-scale physics without fine-tuning must have a radiatively-stable Higgs potential. In little Higgs theories, radiative stability is achieved through so-called collective symmetry breaking. In this letter, we focus on the necessary conditions for a little Higgs to have a collective Higgs quartic cou

  36. Oana Ivanovici, Fabrice Planchon

    The first purpose of this note is to provide a proof of the usual square function estimate on Lp (?). It turns out to follow directly from a generic Mikhlin multiplier theorem obtained by Alexopoulos, which mostly relies on Gaussian bounds on the heat kernel. We also provide a simple proof of a weaker version of the square function estimate, which is enough

  37. Jacques Gabarro-Arpa

    In a previous work a procedure was decribed for dividing the $3 \times N$-dimensional conformational space of a molecular system into a number of discrete cells, this partition allowed the building of a combinatorial structure from data sampled in molecular dynamics trajectories: the graph of cells or G, encoding the set of cells in conformational space that

  38. Francesco Giacosa

    In this proceeding the emergence of a composite, adjoint-scalar field as an average over (trivial holonomy) calorons and anti-calorons is reviewed. This composite field acts as a background field to the dynamics of perturbative gluons, to which is coupled via an effective, gauge invariant Lagrangian valid for temperatures above the deconfinement phase transi

  39. Roberto Notari, Ignacio Ojeda, Maria Luisa Spreafico

    In this paper, we study double structures supported on rational normal curves. After recalling the general construction of double structures supported on a smooth curve described in \cite{fer}, we specialize it to double structures on rational normal curves. To every double structure we associate a triple of integers $ (2r,g,n) $ where $ r $ is the degree of

  40. Igor A. Bandos

    In search for a dynamical description of Q7-branes, which were known as solutions of supergravity equations and then conjectured to be dynamical objects of type IIB string theory, we study the superembedding description of 7-branes in curved type IIB supergravity superspace. With quite minimal and natural assumptions we have found that there is no place for

  41. Giovanni Amelino-Camelia, Giulia Gubitosi, Flavio Mercati

    Motivation for the study of spacetime noncommutativity comes primarily from its possible use in investigations of (Planck-scale) spacetime fuzziness, but most work focuses on S-matrix/field-theory observables and still very little has been established for geometric observables. We argue that it might be useful to exploit the &#34;pregeometric&#34; formulatio

  42. N. Clauvelin, B. Audoly, S. Neukirch

    We derive solutions of the Kirchhoff equations for a knot tied on an infinitely long elastic rod subjected to combined tension and twist. We consider the case of simple (trefoil) and double (cinquefoil) knots; other knot topologies can be investigated similarly. The rod model is based on Hookean elasticity but is geometrically non-linear. The problem is form

  43. Syksy Rasanen

    We derive the redshift and the angular diameter distance in rotationless dust universes which are statistically homogeneous and isotropic, but have otherwise arbitrary geometry. The calculation from first principles shows that the Dyer-Roeder approximation does not correctly describe the effect of clumping. Instead, the redshift and the distance are determin

  44. Stephen P. Shipman

    For the problem of diffraction of harmonic scalar waves by a lossless periodic slab scatterer, we analyze field sensitivity with respect to the material coefficients of the slab. The governing equation is the Helmholtz equation, which describes acoustic or electromagnetic fields. The main theorem establishes the variational Frechet derivative of the scattere

  45. Marc A. Rieffel

    The coadjoint orbits of compact Lie groups carry many K\"ahler structures, which include a Riemannian metric and a complex structure. We provide a fairly explicit formula for the Levi-Civita connection of the Riemannian metric, and we use the complex structure to give a fairly explicit construction of a canonical Dirac operator for the Riemannian metric, in

  46. Michael J. Butler, Jonathan C. Tan

    (Abridged) We use 8 micron Spitzer GLIMPSE images to make extinction maps of 10 IRDCs, selected to be relatively nearby and massive. The extinction mapping technique requires modeling the IR background intensity behind the cloud, which is achieved by correcting for foreground emission and then interpolating from the surrounding regions. The correction for fo

  47. Ilka Brunner, Manfred Herbst

    We study parity symmetries and boundary conditions in the framework of gauged linear sigma models. This allows us to investigate the Kaehler moduli dependence of the physics of D-branes as well as orientifolds in a Calabi-Yau compactification. We first determine the parity action on D-branes and define the set of orientifold-invariant D-branes in the linear

  48. Juliane Behrend

    The averaging problem in general relativity concerns the difficulty of defining meaningful averages of tensor quantities and we consider various aspects of the problem. We first address cosmological backreaction which arises because the averaged Einstein tensor is not the same as the Einstein tensor of the averaged metric. It has been suggested that backreac

  49. Oyvind Gron

    In the present article we analyze, by means of the statefinder parameter formalism, some universe models introduced by Brevik and co-workers. We determine constants that earlier were left unspecified, in terms of observable quantities. It is verified that a Big Bang universe model with a fluid having a certain non-linear equation of state behaves in the same

  50. Gaston Giribet, Lorena Nicolás

    Recently, exact agreement has been found between bulk and boundary three-point functions in AdS_3 x S^3 x T^4 with NSNS fluxes. This represents a non-trivial check of AdS/CFT correspondence beyond the supergravity approximation as it corresponds to an exact worldsheet computation. When taking a closer look at this computation, one notices that a crucial poin

  51. Elisa Vasquez Rifo

    We use the Cauchy-Crofton formula to show that every definable cell (bounded by a ball with rational radius) in an O-minimal expansion of a field extension of the real numbers satisfies the Whitney arc property.

  52. Kolja Knauer, Piotr Micek, Torsten Ueckerdt

    Given two players alternately picking pieces of a pizza sliced by radial cuts, in such a way that after the first piece is taken every subsequent chosen piece is adjacent to some previously taken piece, we provide a strategy for the starting player to get 4/9 of the pizza. This is best possible and settles a conjecture of Peter Winkler.

  53. Jeremy Clark, Wojciech De Roeck, Christian Maes

    We study a general class of translation invariant quantum Markov evolutions for a particle on $\bbZ^d$. The evolution consists of free flow, interrupted by scattering events. We assume spatial locality of the scattering events and exponentially fast relaxation of the momentum distribution. It is shown that the particle position diffuses in the long time limi

  54. R. R. Metsaev

    Conformal self-dual fields in flat space-time of even dimension greater than or equal to four are studied. Ordinary-derivative formulation of such fields is developed. Gauge invariant Lagrangian with conventional kinetic terms and corresponding gauge transformations are obtained. Gauge symmetries are realized by involving the Stueckelberg fields. Realization

  55. Pawel Gawrychowski, Travis Gagie

    A minimax tree is similar to a Huffman tree except that, instead of minimizing the weighted average of the leaves&#39; depths, it minimizes the maximum of any leaf&#39;s weight plus its depth. Golumbic (1976) introduced minimax trees and gave a Huffman-like, $\Oh{n \log n}$-time algorithm for building them. Drmota and Szpankowski (2002) gave another $\Oh{n \

  56. An-Li Tsai, Satoki Matsushita, Kouichiro Nakanishi, Kotaro Kohno

    We present results from a deep (1 sigma = 5.7 mJy beam^{-1} per 20.8 km s^{-1} velocity channel) ^{12}CO(1-0) interferometric observation of the central 60&#34; region of the nearby edge-on starburst galaxy NGC 2146 observed with the Nobeyama Millimeter Array (NMA). Two diffuse expanding molecular superbubbles and one molecular outflow are successfully detec

  57. Joseph G. Checkelsky, N. P. Ong

    We report measurements of the thermopower $S$ and Nernst signal $S_{yx}$ in graphene in a magnetic field $H$. Both quantities show strong quantum oscillations vs. the gate voltage $V_g$. Our measurements for Landau Levels of index $n\ne 0$ are in quantitative agreement with the edge-current model of Girvin and Jonson (GJ). The inferred off-diagonal thermoele

  58. J. M. Fink, R. Bianchetti, M. Baur, M. Goeppl

    We present an ideal realization of the Tavis-Cummings model in the absence of atom number and coupling fluctuations by embedding a discrete number of fully controllable superconducting qubits at fixed positions into a transmission line resonator. Measuring the vacuum Rabi mode splitting with one, two and three qubits strongly coupled to the cavity field, we

  59. Xavier Andrade, Alberto Castro, David Zueco, J. L. Alonso

    We present in detail the recently derived ab-initio molecular dynamics (AIMD) formalism [Phys. Rev. Lett. 101 096403 (2008)], which due to its numerical properties, is ideal for simulating the dynamics of systems containing thousands of atoms. A major drawback of traditional AIMD methods is the necessity to enforce the orthogonalization of the wave-functions

  60. G. Bozzi, S. Catani, G. Ferrera, D. de Florian

    We consider transverse-momentum (q_T) resummation for Drell--Yan lepton pair production in hadron collisions. At small values of q_T, the logarithmically-enhanced QCD contributions are resummed up to next-to-leading logarithmic accuracy. At intermediate and large values of q_T, resummation is consistently combined with the fixed-order perturbative result. We

  61. Huayi Chen

    We introduce the positive intersection product in Arakelov geometry and prove that the arithmetic volume function is continuously differentiable. As applications, we compute the distribution function of the asymptotic measure of a Hermitian line bundle and several other arithmetic invariants.

  62. Philippe Brax, Carsten van de Bruck, Lisa M. H. Hall, Joel M. Weller

    In models of coupled dark energy, in which a dark energy scalar field couples to other matter components, it is natural to expect a coupling to the inflaton as well. We explore the consequences of such a coupling in the context of single field slow-roll inflation. Assuming an exponential potential for the quintessence field we show that the coupling to the i

  63. Fabien Pazuki

    This paper contains results concerning a conjecture made by Lang and Silverman predicting a lower bound for the canonical height on abelian varieties of dimension 2 over number fields. The method used here is a local height decomposition. We derive as corollaries uniform bounds on the number of torsion points on families of abelian surfaces and on the number

  64. Tomi Ylinen, Yvonne Edmonds, Elliott D. Bloom, Jan Conrad

    Dark matter constitutes one of the most intriguing but so far unresolved issues in physics today. In many extensions of the Standard Model the existence of a stable Weakly Interacting Massive Particle (WIMP) is predicted. The WIMP is an excellent dark matter particle candidate and one of the most interesting scenarios include an annihilation of two WIMPs int

  65. Thomas Richardson, Peter J. Mucha, Mason A. Porter

    We formulate a spectral graph-partitioning algorithm that uses the two leading eigenvectors of the matrix corresponding to a selected quality function to split a network into three communities in a single step. In so doing, we extend the recursive bipartitioning methods developed by Newman [Proc. Nat. Acad. Sci. 103, 8577 (2006); Phys. Rev. E 74, 036104 (200

  66. Ujjaini Alam, Varun Sahni, Alexei A. Starobinsky

    For a large class of dark energy (DE) models, for which the effective gravitational constant is a constant and there is no direct exchange of energy between DE and dark matter (DM), knowledge of the expansion history suffices to reconstruct the growth factor of linearized density perturbations in the non-relativistic matter component on scales much smaller t

  67. Amr Elmasry

    We give a priority queue that achieves the same amortized bounds as Fibonacci heaps. Namely, find-min requires O(1) worst-case time, insert, meld and decrease-key require O(1) amortized time, and delete-min requires $O(\log n)$ amortized time. Our structure is simple and promises an efficient practical behavior when compared to other known Fibonacci-like hea

  68. Fabien Pazuki

    The aim of this paper is to study a conjecture predicting a lower bound on the canonical height on abelian varieties, formulated by S. Lang and generalized by J. H. Silverman. We give here an asymptotic result on the height of Heegner points on the modular jacobian $J_{0}(N)$, and we derive non-trivial remarks about the conjecture.

  69. Claus Kiefer, Joao Marto, Paulo Vargas Moniz

    We discuss the dynamics of two harmonic oscillators of which one has a negative kinetic term. This model mimics the Hamiltonian in quantum geometrodynamics, which possesses an indefinite kinetic term. We solve for the time evolution in both the uncoupled and coupled case. We use this setting as a toy model for studying some possible aspects of the final stag

  70. E. Athanassoula, M. Romero-Gomez, J. J. Masdemont

    Two-armed, grand design spirals and inner and outer rings in barred galaxies can be due to orbits guided by the manifolds emanating from the vicinity of the L1 and L2 Lagrangian points, located at the ends of the bar. We first summarise the necessary theoretical background and in particular we describe the dynamics around the unstable equilibrium points in b

  71. Emmanuel Vantieghem

    We present a primality criterium based on congruences for cyclotomic polynomials, and point out a way to generalize our result in order to obtain a family of similar criteria. No practical use is aimed however.

  72. Davide Pietrobon, Paolo Cabella, Amedeo Balbi, Giancarlo de Gasperis

    We look for a non-Gaussian signal in the WMAP 5-year temperature anisotropy maps by performing a needlet-based data analysis. We use the foreground-reduced maps obtained by the WMAP team through the optimal combination of the W, V and Q channels, and perform realistic non-Gaussian simulations in order to constrain the non-linear coupling parameter $\fnl$. We

  73. Ryo Ichimiya, Nicole Apadula, Yasuyuki Akiba, Ermias Atomssa

    We have developed a silicon pixel detector to enhance the physics capabilities of the PHENIX experiment. This detector, consisting of two layers of sensors, will be installed around the beam pipe at the collision point and covers a pseudo-rapidity of | \eta | < 1.2 and an azimuth angle of | \phi | ~ 2{\pi}. The detector uses 200 um thick silicon sensors and

  74. Dongsu Bak

    We study the fermion zero-mode dynamics for open strings ending on the giant graviton branes. For the open string ending on the Z=0 brane, the quantization of the fermion zero-modes of boundary giant magnons reproduces the 256 states of the boundary degrees with the precise realization of the SU(2|2) X SU(2|2) symmetry algebra. Also for the open string endin

  75. S. Domdey, D. Grunewald, B. Z. Kopeliovich, H. J. Pirner

    Using a three stage model of hadron formation we calculate the change of the transverse momentum distribution of hadrons produced in semi-inclusive deep inelastic scattering (SIDIS) on nuclei. In the first stage after its interaction with the virtual photon, the struck quark propagates quasi free in the nuclear environment undergoing multiple collisions with

  76. Yuri A. Rylov

    It is shown, that the conventional presentation of the Maxwell equations for the electromagnetic field in the Riemannian space-time appears to be problematic. The reason of hesitations is the fact, that a solution of the Maxwell equations in the space-time of Minkowski do not turn into solution of the Maxwell equations in the Riemannian space-time after repl

  77. Sheldon Stone, Liming Zhang

    Heavy, as yet undiscovered particles, can affect measurements of CP violation in the B system. Measuring CP violation in the Bs system provides an excellent place to observe such effects since Standard Model sources are predicted to produce very small effects. The angle -2beta_s, the &#34;phase of Bs-\bar{B}s mixing,&#34; thought to be best measured in Bs ->

  78. Massimo Mannarelli

    The properties of cold and dense quark matter have been the subject of extensive investigation, especially in the last decade. Unfortunately, we still lack of a complete understanding of the properties of matter in these conditions. One possibility is that quark matter is in a color superconducting phase which is characterized by the formation of a diquark c

  79. Tobias Ahsendorf

    We use the Graph Minor Theorem to characterize infinite sequences of finite subsets of factorial and commutative semigroups (here semigroups have a unity element), e.g. the multiplicative semigroup of a unique factorization domain.

  80. Bogdan Ranguelov, Ivan Markov

    We study the behavior of single atoms on an infinite vicinal surface assuming certain degree of step permeability. Assuming complete lack of re-evaporation an ruling out nucleation the atoms will inevitably join kink sites at the steps but can do many attempts before that. Increasing the probability of step permeability or the kink spacing lead to increase o

  81. William Y. C. Chen, Henry Y. Gao, Kathy Q. Ji, Martin Y. X. Li

    We obtain a unification of two refinements of Euler&#39;s partition theorem respectively due to Bessenrodt and Glaisher. A specialization of Bessenrodt&#39;s insertion algorithm for a generalization of the Andrews-Olsson partition identity is used in our combinatorial construction.

  82. Merced Montesinos, Mercedes Velazquez

    The Husain-Kuchar theory is a four-dimensional background-independent model that has long been viewed as a useful model for addressing several conceptual and technical problems appearing in the quantization of general relativity mainly in the loop quantum gravity approach. The model was defined at Lagrangian level in terms of a su(2)-valued connection one-fo

  83. T. Fujihara, D. Kimura, T. Inagaki, A. Kvinikhidze

    We investigate color superconducting phase at high density in the extended Nambu--Jona-Lasinio model for the two flavor quarks. Because of the non-renormalizability of the model, physical observables may depend on the regularization procedure, that is why we apply two types of regularization, the cut-off and the dimensional one to evaluate the phase structur

  84. S. V. Shevchenko, V. V. Tokarevsky

    In our previous articles (&#34;The Information and the Matter&#34;, v1, v5; more systematically the informational conception is presented in arXiv paper &#34;The Information as Absolute&#34;, 2010) it was rigorously shown that the Matter is some informational system (structure), which is an [practically] infinitesimal sub-sets of the utmost infinite and fund

  85. Mathieu Rosenbaum, Alexandre B. Tsybakov

    We consider the model {eqnarray*}y=Xθ^*+ξ, Z=X+Ξ,{eqnarray*} where the random vector $y\in\mathbb{R}^n$ and the random $n\times p$ matrix $Z$ are observed, the $n\times p$ matrix $X$ is unknown, $Ξ$ is an $n\times p$ random noise matrix, $ξ\in\mathbb{R}^n$ is a noise independent of $Ξ$, and $θ^*$ is a vector of unknown parameters to be estimated. The matrix

  86. E. Eriksen, O. Gron

    An observer at rest in a uniformly accelerated reference frame experiences a parallel gravitational field, where the rays of light are formed as circular arcs instead of being straight lines. We deduce how a sphere at rest in the Rindler frame, and a freely falling sphere, will appear to an observer at rest in the frame.

  87. Eugene Kang, Myungshin Im

    We report the discovery of possible overdensities of galaxies at z ~ 3.7 in the Chandra Deep Field South (CDF-S). These overdensities are identified from the photometric redshift selected sample, and the BVz-selected sample. One over-density is identified in the proximity of 2 AGNs and LBGs at z=3.66 and z=3.70 at 7-sigma significance level. The other over-d

  88. P. A. Curran, R. L. C. Starling, A. J. van der Horst, R. A. M. J. Wijers

    The complex structure of the light curves of Swift GRBs has made the identification of breaks, and the interpretation of the blast wave caused by the burst, more difficult than in the pre-Swift era. We aim to identify breaks, which are possibly hidden, and to constrain the blast wave parameters; electron energy distribution, p, density profile of the circumb

  89. Stefano Giaccari, Pietro Menotti

    Exact consistent gravitational anomalies for chiral bosons in two dimensions are treated both with the Schwinger-DeWitt regularization and independently through a cohomological procedure. The diffeomorphism transformations are described by a single ghost which allows to climb the cohomological chain in a unique way.

  90. A. Alvermann, H. Fehske

    We propose a general numerical approach to open quantum systems with a coupling to bath degrees of freedom. The technique combines the methodology of polynomial expansions of spectral functions with the sparse grid concept from interpolation theory. Thereby we construct a Hilbert space of moderate dimension to represent the bath degrees of freedom, which all

  91. T. Ferraro, A. Coniglio, M. Zannetti

    We present a theoretical study of a system with competing short-range ferromagnetic attraction and a long-range anti-ferromagnetic repulsion, in the presence of a uniform external magnetic field. The interplay between these interactions, at sufficiently low temperature, leads to the self-tuning of the magnetization to a value which triggers phase coexistence

  92. W. J. Kim, A. O. Sushkov, D. A. R. Dalvit, S. K. Lamoreaux

    We have measured the short-range attractive force between crystalline Ge plates, and found contributions from both the Casimir force and an electrical force possibly generated by surface patch potentials. Using a model of surface patch effects that generates an additional force due to a distance dependence of the apparent contact potential, the electrical fo

  93. Poul H. Damgaard, Hidenori Fukaya

    Chiral perturbation theory at finite four-volume V (=L^3T) is reconsidered with a view towards finding a computational scheme that can deal with any value of M_πL, where M_πis a generic Nambu-Goldstone mass. The momentum zero modes that cause the usual p-expansion to fail in the chiral limit are treated separately, and partly integrated out to all orders. In

  94. Nikolai Nikolov, Peter Pflug, Wlodzimierz Zwonek

    Geometric lower and upper estimates are obtained for invariant metrics on $\Bbb C$-convex domains containing no complex lines.

  95. Brent Everitt, John Fountain

    This is the first of a series of papers in which we initiate and develop the theory of reflection monoids, motivated by the theory of reflection groups. The main results identify a number of important inverse semigroups as reflection monoids, introduce new examples, and determine their orders.

  96. Andrej El, Zhe Xu, Carsten Greiner, Azwinndini Muronga

    Using Grad&#39;s method, we calculate the entropy production and derive a formula for the second-order shear viscosity coefficient in a one-dimensionally expanding particle system, which can also be considered out of chemical equilibrium. For a one-dimensional expansion of gluon matter with Bjorken boost invariance, the shear tensor and the shear viscosity t

  97. Zoran Ristivojevic

    We consider a thin superconducting film with a magnetic dot with permanent magnetization (normal to the film) placed on it by a method based on London-Maxwell equations. For sufficiently high dot magnetization a single vortex appears in the ground state. Further increase of magnetization is accompanied with the appearance of antivortices and more vortices in

  98. Joydeep Chakrabortty, Amitava Raychaudhuri

    Quantum gravity or string compactification can lead to effective dimension-5 operators in Grand Unified Theories which modify the gauge kinetic terms. We exhaustively discuss the group-theoretic nature of such operators for the popular SU(5), SO(10), and E(6) models. In particular, for SU(5) only a Higgs in the 200 representation can help bring the couplings

  99. Andrew Swann

    A twist construction for manifolds with torus action is described generalising certain T-duality examples and constructions in hypercomplex geometry. It is applied to complex, SKT, hypercomplex and HKT manifolds to construct compact simply-connected examples. In particular, we find hypercomplex manifolds that admit no compatible HKT metric, and HKT manifolds

  100. Joydeep Chakrabortty, Amol Dighe, Srubabati Goswami, Shamayita Ray

    We consider the standard model extended by heavy right handed fermions transforming as triplets under SU(2)$_L$, which generate neutrino masses through the Type-III seesaw mechanism. At energies below their respective mass scales, the heavy fields get sequentially decoupled to give an effective dimension-5 operator. Above their mass thresholds, these fields