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April 2006 arXiv papers — page 21

Showing 2,0012,100 of 3,886 papers

  1. Xiangdong Ji, Jian-Wei Qiu, Werner Vogelsang, Feng Yuan

    We study the single-transverse spin asymmetry in semi-inclusive hadron production in deep inelastic scattering. We derive the leading contribution to the asymmetry at moderate transverse momentum $P_{h\perp}$ of the produced hadron in terms of twist-three quark-gluon correlation functions, and compare with the approach based on the factorization at fixed tra

  2. Zhou Ya-Jin, Ma Wen-Gan, Zhang Ren-You, Jiang Yi

    We present the full ${\cal O}(α_{ew})$ electroweak radiative corrections to the Higgs-boson production in association with $Z^0$-boson pair at an electron-positron linear collider(LC) in the standard model. We analyze the dependence of the full one-loop corrections on the Higgs-boson mass $m_{H}$ and colliding energy $\sqrt{s}$. We find that the corrections

  3. The BABAR Collaboration, B. Aubert

    We present the first measurement of $Υ(4S)$ decays to $π^+pi^-Υ(1S)$ and $π^+pi^-Υ(2S)$ based on a sample of 230$\times10^6$ $Υ(4S)$ mesons collected with the BABAR detector. We measure the product branching fractions ${\cal B}(Υ(4S)\to π^+pi^-Υ(1S))\times{\cal B}(Υ(1S)\toμ^+μ^-)=(2.23\pm0.25_{stat} \pm0.27_{sys})\times 10^{-6}$ and ${\cal B}(Υ(4S)\to π^+pi^

  4. Liang Wu

    Feature extraction and matching are among central problems of computer vision. It is inefficent to search features over all locations and scales. Neurophysiological evidence shows that to locate objects in a digital image the human visual system employs visual attention to a specific object while ignoring others. The brain also has a mechanism to search from

  5. Mohamed Laradji, P. B. Sunil Kumar

    The effect of asymmetry in the transbilayer lipid distribution on the dynamics of phase separation in fluid vesicles is investigated numerically for the first time. This asymmetry is shown to set a spontaneous curvature for the domains that alter the morphology and dynamics considerably. For moderate tension, the domains are capped and the spontaneous curvat

  6. Paul Larson, Walter R. L. Lambrecht

    A computational study of the electronic structure and magnetic properties of Gd-pnictides is reported. The calculations were performed using a full-potential linear muffin-tin orbital (LMTO) method within the so-called LSDA+U approach, which adds Hubbard-U correlation effects to specified narrow bands in a mean-field approach to the local spin density approx

  7. P. Buonsante, P. Kevrekidis, V. Penna, A. Vezzani

    We investigate the ground state of a system of interacting particles in small nonlinear lattices with M > 2 sites, using as a prototypical example the discrete nonlinear Schroedinger equation that has been recently used extensively in the contexts of nonlinear optics of waveguide arrays, and Bose-Einstein condensates in optical lattices. We find that, in the

  8. W. J. Mullin, R. Krotkov, F. Laloë

    We consider the interference of two overlapping ideal Bose-Einstein condensates. The usual description of this phenomenon involves the introduction of a so-called condensate wave functions having a definite phase. We investigate the origin of this phase and the theoretical basis of treating interference. It is possible to construct a phase state, for which t

  9. K. Ishizaka, R. Eguchi, S. Tsuda, T. Yokoya

    We have investigated the low energy electronic state of a boron-doped diamond thin film by the ultrahigh resolution laser-excited photoemission spectroscopy. We observed a clear shift of the leading edge below 11 K indicative of a superconducting gap opening ($Δ\sim 0.78$ meV at 4.5 K). The gap feature is significantly broad and the well-defined quasiparticl

  10. Vincent Richefeu, Moulay Saïd El Youssoufi, Farhang Radjaï

    We investigate shear strength properties of wet granular materials in the pendular state (i.e. the state where the liquid phase is discontinuous) as a function of water content. Sand and glass beads were wetted and tested in a direct shear cell and under various confining pressures. In parallel, we carried out three-dimensional molecular dynamics simulations

  11. M. -H. Tsai, Y. -H. Tang, H. Chou, W. T. Wu

    The complicated electronic, magnetic, and colossal magnetoresistant (CMR) properties of Sr and Ca doped lanthanum manganites can be understood by spin-polarized first-principles calculations. The electronic properties can be attributed to a detailed balancing between Sr and Ca induced metal-like O 2p and majority-spin (majority-spin) Mn eg delocalized states

  12. M. -H Tsai, S. K. Dey

    To date, the generic polarization of Bernardini, Fiorentini and Vanderbilt (PBFV) has been widely used to address the issue of polarity in III-V nitride semiconductors, but improvements in nitride materials and the performance of optoelectronic devices have been limited. The current first-principles calculation for the electronic structures of nm-scale [0001

  13. D. A. Pesin, A. V. Andreev

    We study superconductivity suppression due to thermal fluctuations in disordered wires using the replica nonlinear $σ$-model ($NLσM$). We show that in addition to the thermal phase slips there is another type of fluctuations that result in a finite resistivity. These fluctuations are described by saddle points in $NLσM$ and cannot be treated within the Ginzb

  14. Victor A. Gopar, Stefan Rotter, Henning Schomerus

    We investigate the effect of spatial symmetries on phase coherent electronic transport through chaotic quantum dots. For systems which have a spatial symmetry that interchanges the source and drain leads, we find in the framework of random matrix theory that the density of the transmission eigenvalues is indepedent of the number of channels N in the leads. A

  15. I. A. Nechaev, E. V. Chulkov

    We present a detailed study of a contribution of the T matrix accounting for multiple scattering between an electron and a hole to the quasiparticle self-energy. This contribution is considered as an additional term to the GW self-energy. The study is based on a variational solution of the T-matrix integral equation within a local approximation. A key quanti

  16. E. Schachinger, D. Neuber, J. P. Carbotte

    Optical data is encoded with information on the microscopic interaction between charge carriers. For an electron-phonon system, the Eliashberg equations apply and a Kubo formula can be used to get the infrared conductivity. The task of extracting the electron-phonon spectral density $α^2F(ω)$ from data is rather complicated and, thus, simplified but approxim

  17. Beth A. Biller, Laird M. Close, Aigen Li, Massimo Marengo

    We imaged the symbiotic star CH Cyg and two PSF calibration stars using the unique 6.5m MMT deformable secondary adaptive optics system. Our high-resolution (FWHM=0.3"), very high Strehl (98%+-2%) mid-infrared (9.8 and 11.7 um) images of CH Cyg allow us to probe finer length scales than ever before for this object. CH Cyg is significantly extended compar

  18. Regina A. Jorgenson, Arthur M. Wolfe, Jason X. Prochaska, Limin Lu

    As large optical quasar surveys for damped Lya become a reality and the study of star forming gas in the early Universe achieves statistical robustness, it is now vital to identify and quantify the sources of systematic error. Because the nature of optically-selected quasar surveys makes them vulnerable to dust obscuration, we have undertaken a radio-selecte

  19. Andrea Stolte, Wolfgang Brandner, Bernhard Brandl, Hans Zinnecker

    Based on deep VLT/ISAAC JHK photometry, we have derived the present-day mass function of the central starburst cluster NGC 3603 YC (Young Cluster) in the giant HII region NGC 3603. The effects of field contamination, individual reddening, and a possible binary contribution are investigated. The MF slopes resulting from the different methods are compared, and

  20. Edmund C. Sutton, Benjamin D. Wandelt

    We introduce a method for analyzing radio interferometry data which produces maps which are optimal in the Bayesian sense of maximum posterior probability density, given certain prior assumptions. It is similar to maximum entropy techniques, but with an exact accounting of the multiplicity instead of the usual approximation involving Stirling's formula.

  21. P. Monaco

    We discuss the role of feedback from AGNs on the formation of spheroidal galaxies. The energy released by an accreting Black Hole (BH) may be injected into the ISM through blast waves arising directly from the central engine, radiation pressure or radiative heating. A scenario is described in which radiative heating perturbs the methabolism of a star-forming

  22. Z. Bagoly, A. Mészáros, L. G. Balázs, I. Horváth

    Until 6 October 2005 sixteen redshifts have been measured of long gamma-ray bursts discovered by the Swift satellite. Further 45 redshifts have been measured of the long gamma-ray bursts discovered by other satellites. Here we perform five statistical tests comparing the redshift distributions of these two samples assuming - as the null hypothesis - identica

  23. V. Tatischeff, B. Kozlovsky, J. Kiener, R. J. Murphy

    We have studied the radioactive line emission expected from solar active regions after large flares, following the production of long-lived radioisotopes by nuclear interactions of flare-accelerated ions. This delayed X- and gamma-ray line emission can provide unique information on the accelerated particle composition and energy spectrum, as well as on mixin

  24. Carlos Hernandez-Monteagudo, Licia Verde, Raul Jimenez

    We study the constraints that future multifrequency Cosmic Microwave Background (CMB) experiments will be able to set on the metal enrichment history of the Inter Galactic Medium at the epoch of reionisation. We forecast the signal to noise ratio for the detection of the signal introduced in the CMB by resonant scattering off metals at the end of the Dark Ag

  25. Brian A. Keeney, Charles W. Danforth, John T. Stocke, Steven V. Penton

    We detect high-velocity absorbing gas using Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer medium resolution spectroscopy along two high-latitude AGN sight lines (Mrk 1383 and PKS 2005-489) above and below the Galactic Center (GC). These absorptions are most straightforwardly interpreted as a wind emanating from the GC which does not escap

  26. S. A. Rodney, J. L. Tonry

    We demonstrate the effectiveness of two techniques for using x-rays to evaluate the amount of charge diffusion in charge coupled devices (CCDs). We quantify the degree of charge diffusion with two parameters: sigma_d, the standard deviation for a Gaussian diffusion model, and Q, a ratio of the point spread function (PSF) peak to its wings. sigma_d and Q are

  27. C. M. Gutierrez, M. S. Alonso, J. G. Funes, M. B. Ribeiro

    We present narrow-band observations of the H$α$ emission in a sample of 31 satellite orbiting isolated giant spiral galaxies. The sample studied spans the range $-19<M_B <-15$ mag. The H$α$ emission was detected in all the spiral and irregular objects with fluxes in the range $1.15-49.80\times 10^{-14}$ erg cm$^{-2}$ s$^{-1}$. The average and maximum values

  28. J. Bouvier, S. H. P. Alencar, T. J. Harries, C. M. Johns-Krull

    The inner 0.1 AU around accreting T Tauri stars hold clues to many physical processes that characterize the early evolution of solar-type stars. The accretion-ejection connection takes place at least in part in this compact magnetized region around the central star, with the inner disk edge interacting with the star&#39;s magnetosphere thus leading simultane

  29. Shugo Michikoshi, Shu-ichiro Inutsuka

    We analyze the stability of dust layer in protoplanetary disk to understand the effect of the relative motion between gas and dust. The previous analyses not including the effect of relative motion between gas and dust show that the shear-induced turbulence may prevent the dust grains from settling sufficiently to be gravitationally unstable. We determine th

  30. Edwin A. Henneken, Michael J. Kurtz, Guenther Eichhorn, Alberto Accomazzi

    In this report we examine the change in citation behavior since the introduction of the arXiv e-print repository (Ginsparg, 2001). It has been observed that papers that initially appear as arXiv e-prints get cited more than papers that do not (Lawrence, 2001; Brody et al., 2004; Schwarz & Kennicutt, 2004; Kurtz et al., 2005a, Metcalfe, 2005). Using the citat

  31. Charles P. Boyer, Krzysztof Galicki, Santiago R. Simanca

    Let $M$ be a closed manifold of Sasaki type. A polarization of $M$ is defined by a Reeb vector field, and for one such, we consider the set of all Sasakian metrics compatible with it. On this space, we study the functional given by the squared $L^2$-norm of the scalar curvature. We prove that its critical points, or canonical representatives of the polarizat

  32. Karol Kampf, Bachir Moussallam

    We derive constraints on combinations of O(p^6) chiral coupling constants by matching a recent two-loop calculation of the pi-K scattering amplitude with a set of sum rules. We examine the validity of the natural expectation that the values of the chiral couplings can be associated with physics properties of the light resonance sector. We focus, in particula

  33. David N. Burrows, Dirk Grupe, Milvia Capalbi, Alin Panaitescu

    We report the best evidence to date of a jet break in a short Gamma-Ray Burst (GRB) afterglow, using Chandra and Swift XRT observations of the X-ray afterglow of GRB 051221A. The combined X-ray light curve, which has three breaks, is similar to those commonly observed in Swift observations of long GRBs. A flat segment of the light curve at ~0.1 days after th

  34. S. Deboeuf, E. Lajeunesse, O. Dauchot, B. Andreotti

    Unconfined granular flows along an inclined plane are investigated experimentally. During a long transient, the flow gets confined by quasistatic banks but still spreads laterally towards a well-defined asymptotic state following a nontrivial process. Far enough from the banks a scaling for the depth averaged velocity is obtained, which extends the one obtai

  35. Keisuke Okamura, Kentaroh Yoshida

    We propose a perturbative asymptotic Bethe ansatz (PABA) for open spin-chain systems whose Hamiltonians are given by matrices of anomalous dimension for composite operators, and apply it to two types of composite operators related to two different brane configurations. One is an AdS_4 \times S^2-brane in the bulk AdS_5 \times S^5 which gives rise to a defect

  36. Eun-Ah Kim

    We compute the temperature, voltage, and magnetic field dependences of the resistance oscillations of a model interferometer designed to measure the fractional statistics of the quasiparticles in the fractional quantum Hall (FQH) effect. The geometry is the same as that used in recent experiments reported in Refs. \cite{camino-prl,camino-T,zhou}. With approp

  37. S. T. Holland, P. T. Boyd, J. Gorosabel, J. Hjorth

    We present ultraviolet, optical, and infrared photometry of the afterglow of the X-ray flash XRF 050416A taken between approximately 100 seconds and 36 days after the burst. We find an intrinsic spectral slope between 1930 and 22,200 Angstrom of beta = -1.14 +/- 0.20 and a decay rate of alpha = -0.86 +/- 0.15. There is no evidence for a change in the decay r

  38. Fabien Bruneval, Francesco Sottile, Valerio Olevano, Lucia Reining

    In the description of the interaction between electrons beyond the classical Hartree picture, bare exchange often yields a leading contribution. Here we discuss its effect on optical spectra of solids, comparing three different frameworks: time-dependent Hartree-Fock, a recently introduced combined density-functional and Green&#39;s functions approach applie

  39. Laszlo P. Csernai, Joseph. I. Kapusta, Larry D. McLerran

    Substantial collective flow is observed in collisions between large nuclei at RHIC (Relativistic Heavy Ion Collider) as evidenced by single-particle transverse momentum distributions and by azimuthal correlations among the produced particles. The data are well-reproduced by perfect fluid dynamics. A calculation of the dimensionless ratio of shear viscosity $

  40. Matteo Viel, Martin G. Haehnelt, Antony Lewis

    A combined analysis of Cosmic Microwave Background (CMB) and Lyman-a forest data allows to constrain the matter power spectrum from small scales of about 1 Mpc/h all the way to the horizon scale. The long lever arm and complementarity provided by such an analysis has previously led to a significant tightening of the constraints on the shape and the amplitude

  41. Adrienne L. Erickcek, Marc Kamionkowski, Andrew J. Benson

    The merger of two supermassive black holes is expected to produce a gravitational-wave signal detectable by the satellite LISA. The rate of supermassive-black-hole mergers is intimately connected to the halo merger rate, and the extended Press-Schechter formalism is often employed when calculating the rate at which these events will be observed by LISA. This

  42. S. M. Kopeikin, A. G. Polnarev, G. Schaefer, I. Yu. Vlasov

    The most precise test of the post-Newtonian gamma parameter in the solar system has been achieved in measurement of the frequency shift of radio waves to and from the Cassini spacecraft as they passed near the Sun. The test relies upon the JPL model of radiowave propagation that includes, but does not explicitly parametrize, the impact of the non-stationary

  43. Ana Júlia Mizher, Eduardo S. Fraga, Gastão Krein

    We investigate the effects of dissipation in the deconfinement transition for pure SU(2) and SU(3) gauge theories. Using an effective theory for the order parameter, we study its Langevin evolution numerically. Noise effects are included for the case of SU(2). We find that both dissipation and noise have dramatic effects on the spinodal decomposition of the

  44. N. Matagne, Fl. Stancu

    The masses of positive $[{\bf 70},0^+]$ and $[{\bf 70},2^+]$ nonstrange and strange baryons are calculated in the $1/N_c$ expansion. The approach is based on the separation of a system of $N_c$ quarks into an excited core and an excited quark. The previous work for two flavor baryons is now extended to include strange baryons, to first order in SU(3)-flavor

  45. John Foster, Ken-ichi Okumura, Leszek Roszkowski

    We discuss the implications, for general flavour mixing, of the recent results regarding the new allowed range for mixing in the $B_s$ meson system, as well as the new improved bounds on $BR(\bar{B}_s\toμ^+μ^-)$. Constraints on right handed insertions, in particular, improve considerably in the large $\tanb$ regime where the contributions to $B_s$ mixing are

  46. W. Liu, R. Rapp

    Within an effective hadronic model including electromagnetic interactions via a U$_{\rm em}$(1) gauge, we reinvestigate photon Bremsstrahlung from a hot hadronic gas as expected to be formed in relativistic heavy-ion collisions at SPS energies. We calculate photon emission from the reactions $ππ\toππγ$ and $πK \toπKγ$ by an explicit (numerical) evaluation of

  47. Paolo Piazza, Thomas Schick

    Let G be a discrete group, and let M be a closed spin manifold of dimension m>3 with pi_1(M)=G. We assume that M admits a Riemannian metric of positive scalar curvature. We discuss how to use the L2-rho invariant and the delocalized eta invariant associated to the Dirac operator on M in order to get information about the space of metrics with positive scalar

  48. Y. -P. Lee

    The main goal of this paper is to introduce a set of conjectures on the relations in the tautological rings. In particular, the framework gives an efficient algorithm to calculate all tautological equations using only finite dimensional linear algebra. Other applications are also indicated.

  49. J. D. McEwen, M. P. Hobson, A. N. Lasenby, D. J. Mortlock

    We repeat the directional spherical real Morlet wavelet analysis used to detect non-Gaussianity in the WMAP 1-year data (McEwen et al. 2005a), on the WMAP 3-year data. The non-Gaussian signal previously detected is indeed present in the 3-year data, although the significance of the detection is reduced. Using our most conservative method for constructing sig

  50. Sébastien Darses, Ivan Nourdin

    In this paper, we introduce some fundamental notions related to the so-called stochastic derivatives with respect to a given $σ$-field $\mathcal{Q}$. In our framework, we recall well-known results about Markov--Wiener diffusions. We then focus mainly on the case where $X$ is a fractional diffusion and where $\mathcal{Q}$ is the past, the future or the presen

  51. Y. -J. Choie, N. Lichiardopol, P. Moree, P. Sole

    Robin's criterion states that the Riemann Hypothesis (RH) is true if and only if Robin's inequality sum_{d|n}d<e^{gamma}n loglog n is satisfied for n>=5041, where gamma denotes the Euler(-Mascheroni) constant. We show by elementary methods that if n>=37 does not satisfy Robin's criterion it must be even and is neither squarefree nor squarefull. Using a bound

  52. C. H. Arthur Cheng, Daniel Coutand, Steve Shkoller

    We study a moving boundary value problem consisting of a viscous incompressible fluid moving and interacting with a nonlinear elastic fluid shell. The fluid motion is governed by the Navier-Stokes equations, while the fluid shell is modeled by a bending energy which extremizes the Willmore functional and a membrane energy that extremizes the surface area of

  53. Tuhin Ghosh, Amir Hajian, Tarun Souradeep

    Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII_h templates in the CMB anisotropy maps to determine whether the existence of a hidden Bianchi template in the WMAP data is consistent with the previous n

  54. J. Hu, G. Sheffer, Yu. I. Davydov, D. R. Gill

    A low mass time expansion chamber (TEC) has been developed to measure distributions of position and angle of the TRIUMF low energy surface muon beam used for the TWIST experiment. The experiment is a high precision measurement of muon decay and is dominated by systematic uncertainties, including the stability, reproducibility, and characterization of the bea

  55. A. A. Ashimova, S. R. Slabospitsky

    Using the constraint on the single top production cross-section obtained at the HERA collider, $σ(ep \to e t X)$, we evaluate an upper limit on oupling constant of the anomalous top quark interaction with a gluon via flavor-changing neutral current: $|κ_{tgq}/Λ| \le 0.4 {TeV}^{-1}$, BR$(t \to gq) < 13 % $

  56. V. Soma, P. Bozek

    In medium T-matrix calculations for symmetric nuclear matter at zero and finite temperatures are presented. The internal energy is calculated from the Galitskii-Koltun&#39;s sum rule and from the summation of the diagrams for the interaction energy. The pressure at finite temperature is obtained from the generating functional form of the thermodynamic potent

  57. T. R. Cass, P. K. Friz

    We extend the Bismut-Elworthy-Li formula to non-degenerate jump diffusions and &#34;payoff&#34; functions depending on the process at multiple future times. In the spirit of Fournie et al [13] and Davis and Johansson [9] this can improve Monte Carlo numerics for stochastic volatility models with jumps. To this end one needs so-called Malliavin weights and we

  58. F. Ghahhari, V. Karimipour, R. Shahrokhshahi

    We investigate the dynamics of an initially disentangled Gaussian state on a general finite symmetric graph. As concrete examples we obtain properties of this dynamics on mean field graphs of arbitrary sizes. In the same way that chains can be used for transmitting entanglement by their natural dynamics, these graphs can be used to store entanglement. We als

  59. S. Duhot, R. Mélin

    We show that a spin-up electron from a normal metal entering a superconductor propagates as a composite object consisting of a spin-down hole and a pair in the condensate. This leads to a factorization of the non local conductance as two local Andreev reflections at both interfaces and one propagation in the superconductor, which is tested numerically within

  60. Aram Saharian, Giampiero Esposito

    Non-local boundary conditions have been considered in theoretical high-energy physics with emphasis on one-loop quantum cosmology, one-loop conformal anomalies, Bose-Einstein condensation models and spectral branes. We have therefore studied the Wightman function, the vacuum expectation value of the field square and the energy-momentum tensor for a massive s

  61. K. Machida, T. Mizushima, M. Ichioka

    It is shown by microscopic calculations for trapped imbalanced Fermi superfluids that the gap function has always sign changes, i.e., the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state like, up to a critical imbalance $P_c$, beyond which normal state becomes stable, at temperature T=0. A phase diagram is constructed in $T$ vs $P$, where the BCS state without

  62. N. N. Nikolaev, W. Schäfer

    We report the first derivation of the Landau-Pomeranchuk-Migdal effect for leading jets at fixed values of the transverse momentum p_t in the beam fragmentation region of hadron-nucleus collisions from RHIC (Relativistic Heavy Ion Collider) to LHC (Large Hadron Collider). The major novelty of this work is a derivation of the missing virtual radiative pQCD co

  63. A. Mirizzi, G. G. Raffelt, P. D. Serpico

    A model-independent experimental signature for flavor oscillations in the neutrino signal from the next Galactic supernova (SN) would be the observation of Earth matter effects. We calculate the probability for observing a Galactic SN shadowed by the Earth as a function of the detector's geographic latitude. This probability depends only mildly on details of

  64. A. Sesana, F. Haardt, P. Madau

    We use full three-body scattering experiments to study the ejection of hypervelocity stars (HVSs) by massive black hole binaries (MBHBs) at the center of galaxies. Ambient stars drawn from a Maxwellian distribution unbound to the binary are expelled by the gravitational slingshot. Accurate measurements of thermally averaged hardening, mass ejection, and ecce

  65. Yong Li, Z. D. Wang, C. P. Sun

    We employ a generalized Dicke model to study theoretically the quantum criticality of an extended two-level atomic ensemble interacting with a single-mode quantized light field. Effective Hamiltonians are derived and diagonalized to investigate numerically their eigenfrequencies for different quantum phases in the system. Based on the analysis of the eigenfr

  66. Cheng-Yi Sun, De-Hai Zhang

    In this paper, we use the result in [7] to calculate the non-Gaussianity of the racetrack models in [3, 5]. The two models give different non- Gaussianities. Both of them are reasonable.

  67. Sang-Woo Kim, D. G. Pak

    The gauge approach to gravity based on the local Lorentz group with a general independent affine connection A_{μcd} is developed. We consider SO(1,3) gauge theory with a Lagrangian quadratic in curvature as a simple model of quantum gravity. The torsion is proposed to represent a dynamic degree of freedom of quantum gravity at scales above the Planckian ener

  68. M. Glück, E. Reya, C. Schuck

    The significance of NNLO (3-loop) QCD contributions to the flavor non-singlet sector of F_2^ep and F_2^ed has been studied as compared to uncertainties (different factorization schemes, higher twist and QED contributions) of standard NLO (and LO) QCD analyses. The latter effects turn out to be comparable in size to the NNLO contributions. Therefore the minut

  69. V. Gogokhia

    We propose to realize a mass gap in QCD by not imposing the transversality condition on the full gluon self-energy, while preserving the color gauge invariance condition for the full gluon propagator. This is justified by the nonlinear and nonperturbative dynamics of QCD. None of physical observables/processes in low-energy QCD will be directly affected by s

  70. Shaaban Khalil

    We analyze supersymmetric contributions to B^- -> D^0 K^- and B^- ->\bar{D}^0 K^- processes. We investigate the possibility that supersymmetric CP violating phases can affect our determination for the angle γin the unitary triangle of Cabibbo-Kobayashi-Maskaw mixing matrix. We calculate the gluino and chargino contributions to b--> u(\bar{c}s) and b-->c(\bar

  71. Fabrice Doveil, Alessandro Macor, Yves Elskens

    We report the experimental observation of a &#34;devil&#39;s staircase&#39;&#39; in a time dependent system considered as a paradigm for the transition to large scale chaos in the universality class of hamiltonian systems. A test electron beam is used to observe its non-self-consistent interaction with externally excited wave(s) in a Travelling Wave Tube (TW

  72. Claudia Pinzari

    The notion of compact quantum subgroup is revisited and an alternative definition is given. Induced representations are considered and a Frobenius reciprocity theorem is obtained. A relationship between ergodic actions of compact quantum groups on C*-algebras and topological transitivity is investigated. A sufficient condition for embedding such actions in q

  73. Hajime Aoki, Jun Nishimura, Yoshiaki Susaki

    We investigate the effects of non-commutative geometry on the topological aspects of gauge theory using a non-perturbative formulation based on the twisted reduced model. The configuration space is decomposed into topological sectors labeled by the index nu of the overlap Dirac operator satisfying the Ginsparg-Wilson relation. We study the probability distri

  74. Metod Saniga, Michel Planat

    The paper gives a succinct appraisal of the properties of the projective line defined over the direct product ring $R\_{\triangle} \equiv$ GF(2)$\otimesGF(2)\otimes$GF(2). The ring is remarkable in that except for unity, all the remaining seven elements are zero-divisors, the non-trivial ones forming two distinct sets of three; elementary (&#39;slim&#39;) an

  75. Chun-Hsien Wu, Kin-Wang Ng, Wolung Lee, Da-Shin Lee

    We propose a new source for the cosmological density perturbation which is passive fluctuations of the inflaton driven dynamically by a colored quantum noise as a result of its coupling to other massive quantum fields. The created fluctuations grow with time during inflation before horizon-crossing. However, the larger-scale modes cross out the horizon earli

  76. Gaku Kiuchi, Kouji Ohta, Masayuki Akiyama, Kentaro Aoki

    We study properties of the host galaxies of 15 hard X-ray selected type-2 active galactic nuclei (AGNs) at intermediate redshifts (0.05$<z<$0.6) detected in $ASCA$ surveys. The absorption corrected hard X-ray luminosities $L_{\rm 2-10 keV}$ range from 10$^{42}$ erg s$^{-1}$ to $10^{45}$ erg s$^{-1}$. We took the $R$-band image of these AGNs with the Universi

  77. Xiao-Gang He, Xue-Qian Li

    In the standard model production of on-shell Z boson at a photon collider (or Z decays into $γγ$) is strictly forbidden by angular momentum conservation and Bose statistics (the Yang&#39;s Theorem). In the standard model with noncommutative space-time this process can occur. Therefore this process provides an important probe for the noncommutative space-time

  78. Patrick Desrosiers, Peter J. Forrester

    The gap probabilities at the hard and soft edges of scaled random matrix ensembles with orthogonal symmetry are known in terms of $τ$-functions. Extending recent work relating to the soft edge, it is shown that these $τ$-functions, and their generalizations to contain a generating function parameter, can be expressed as Fredholm determinants. These same Fred

  79. Jisuke Kubo, Ernest Ma, Daijiro Suematsu

    Two of the most important and pressing questions in cosmology and particle physics are: (1) What is the nature of cold dark matter? and (2) Will near-future experiments on neutrinoless double beta decay be able to ascertain that the neutrino is a Majorana particle, i.e. its own antiparticle? We show that these two seemingly unrelated issues are intimately co

  80. Mark C. Neyrinck, István Szapudi, Christopher D. Rimes

    Using the halo model, we investigate the cosmological Fisher information in the non-linear dark-matter power spectrum about the initial amplitude of linear power. We find that there is little information on `translinear&#39; scales (where the one- and two-halo terms are both significant) beyond what is on linear scales, but that additional information is pre

  81. Misha Verbitsky

    Let (M,I,J,K) be a hyperkahler manifold of real dimension 4n, and L a non-trivial holomorphic line bundle on (M,I). Using the quaternionic Dolbeault complex, we prove the following vanishing theorem for holomorphic cohomology of L. If the Chern class c_1(L) lies in the closure $\hat K$ of the dual Kahler cone, then $H^i(L)=0$ for i>n. If c_1(L) lies in the o

  82. K. J. Challis, R. J. Ballagh, C. W. Gardiner

    We present a theoretical treatment of Bragg scattering of a degenerate Fermi gas in the weakly interacting BCS regime. Our numerical calculations predict correlated scattering of Cooper pairs into a spherical shell in momentum space. The scattered shell of correlated atoms is centered at half the usual Bragg momentum transfer, and can be clearly distinguishe

  83. B. Tian, L. Deng, Z. Han, X. B. Zhang

    In this paper, we present the simulations for the primordial blue stragglers in the old open cluster M67 based on detailed modelling of the evolutionary processes. The principal aim is to discuss the contribution of mass transfer between the components of close binaries to the blue straggler population in M67. First, we followed the evolution of a binary of

  84. V. V. Varlamov

    Matrix elements and spherical functions of irreducible representations of the de Sitter group are studied on the various homogeneous spaces of this group. It is shown that a universal covering of the de Sitter group gives rise to quaternion Euler angles. An explicit form of Casimir and Laplace-Beltrami operators on the homogeneous spaces is given. Different

  85. Efstratios Manousakis

    In the present work, quantum theory is founded on the framework of consciousness, in contrast to earlier suggestions that consciousness might be understood starting from quantum theory. The notion of streams of consciousness, usually restricted to conscious beings, is extended to the notion of a Universal/Global stream of conscious flow of ordered events. Th

  86. Xiaoguang Wang, Z. D. Wang

    A formula to evaluate the entanglement in an one-dimensional ferrimagnetic system is derived. Based on the formula, we find that the thermal entanglement in a small size spin-1/2 and spin-s ferrimagnetic chain is rather robust against temperature, and the threshold temperature may be arbitrarily high when s is sufficiently large. This intriguing result answe

  87. Gen Kimura, Hajime Tanaka, Masanao Ozawa

    The Mean King&#39;s problem with mutually unbiased bases is reconsidered for arbitrary d-level systems. Hayashi, Horibe and Hashimoto [Phys. Rev. A 71, 052331 (2005)] related the problem to the existence of a maximal set of d-1 mutually orthogonal Latin squares, in their restricted setting that allows only measurements of projection-valued measures. However,

  88. Sameer M. Ikhdair, Ramazan Sever

    The analytical solutions of the N-dimensional Schrodinger equation with position-dependent mass for a general class of central potentials is obtained via the series expansion method. The position-dependent mass is expanded in series about origin. As a special case, the analytical bound-state series solutions and the recursion relation of the linear-plus-Coul

  89. Philippe Veber, Michel Le_Borgne, Anne Siegel, Sandrine Lagarrigue

    We advocate the use of qualitative models in the analysis of large biological systems. We show how qualitative models are linked to theoretical differential models and practical graphical models of biological networks. A new technique for analyzing qualitative models is introduced, which is based on an efficient representation of qualitative systems. As show

  90. E. Durand, M. G. B Blum, O. Francois

    We provide a mean-field analysis of community structure of social and biological networks assuming that actors are able to evaluate some tree-derived distance to the other actors and tend to aggregate with the less distant. We show that such networks have small components, and give exact descriptions for the probability distribution of a typical community si

  91. V. Drollinger

    In order to get ready for physics at the LHC, the CMS experiment has to be set up for data taking. The data have to be well understood before new physics can be investigated. On the other hand, there are standard processes, well known from previous experiments and from simulation, which will help to understand the data of the detector in the early days of th

  92. Viatcheslav Berejnov, Naji S. Husseini, Osama A. Alsaied, Robert E. Thorne

    Vitrification of aqueous cryoprotectant mixtures is essential in cryopreservation of proteins and other biological samples. We report systematic measurements of critical cryoprotective agent (CPA) concentrations required for vitrification during plunge cooling from T=295 K to T=77 K in liquid nitrogen. Measurements on fourteen common CPAs including alcohols

  93. V. I. Telnov

    This paper is the second part of my overview on photon colliders given at the conference ``The photon: its first hundred years and the future&#39;&#39; (PHOTON2005 + PLC2005). The first paper describes the first 25 years of the history and evolution of photon colliders. The present paper considers the photon collider at the ILC: possible parameters, technica

  94. Kalimullah, Madhur Garg, P. Arun, F. M. S. Lima

    A simple setup was assembled to study the motion of an object while it falls. The setup was used to determine the instantaneous velocity, terminal velocity and acceleration due to gravity. Also, since the whole project was done within $20 it can easily be popularized.

  95. A. V. Rogacheva, V. A. Fedotov, A. S. Schwanecke, N. I. Zheludev

    We report the first experimental evidence that electromagnetic coupling between physically separated planar metal patterns located in parallel planes provides for exceptionally strong polarization rotatory power if one pattern is twisted in respect to the other, creating a 3D chiral object. In terms of optical rotary power per sample of thickness equal to on

  96. M. Ya. Amusia, A. S. Baltenkov

    Correctness of the model representing the fullerene shell C60 as a conducting sphere has been analyzed. The static and dynamical polarizabilities of the molecule C60 have been calculated on the basis of experimental data on the photo-absorption cross- section of fullerene. It has been shown that the real C60 in the static electric field behaves most likely a

  97. Mark Heinz

    We present measurements of strange and multi-strange hadrons in p+p collisions at $\sqrt{s}$= 200 GeV measured by STAR. We will compare these preliminary results to leading-order (LO) and next-to-leading order (NLO) perturbative QCD models widely believed to describe the production mechanisms. In particular we will point out recent changes of the model calcu

  98. O. G. Chkhetiani, M. Hnatich, E. Jurcisinova, M. Jurcisin

    We have investigated the advection of a passive scalar quantity by incompressible helical turbulent flow in the frame of extended Kraichnan model. Turbulent fluctuations of velocity field are assumed to have the Gaussian statistics with zero mean and defined noise with finite time-correlation. Actual calculations have been done up to two-loop approximation i

  99. M. Hnatich, E. Jurcisinova, M. Jurcisin, M. Repasan

    The influence of compressibility on the stability of the scaling regimes of the passive scalar advected by a Gaussian velocity field with finite correlation time is investigated by the field theoretic renormalization group within two-loop approximation. The influence of compressibility on the scaling regimes is discussed as a function of the exponents $ε$ an

  100. A. Mumtaz, K. Maaz, B. Janjua, S. K. Hasanain

    Magnetic properties of core-shell cobalt ferrite nanoparticles 15 to 48nm prepared by a sol-gel route have been studied. It is shown that the coercivity follows non-monotonic size dependence varying as 1/d above the maximum (d is the particle size). Field cooled magnetization exhibited both horizontal (exchange bias) and vertical shifts. The exchange bias is