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January 2005 arXiv papers — page 5

Showing 401–500 of 3,506 papers

  1. Ortwin Gerhard, Magda Arnaboldi, Kenneth C. Freeman, Nobunari Kashikawa

    [OIII] lambda 5007AA emission lines of 16 intracluster planetary nebulae candidates in the Coma cluster were detected with a Multi-Slit Imaging Spectroscopy (MSIS) technique using FOCAS on the Subaru telescope. The identification of these faint emission sources as PNe is supported by (i) their point-like flux distribution in both space and wavelength, with t

  2. D. Reimers, E. Janknecht, C. Fechner, I. I. Agafonova

    HE 0141-3932 (zem = 1.80) is a bright blue radio-quite quasar with an unusually weak Ly-alpha emission line. Large redshift differences (Delta z = 0.05) are observed between high ionization and low ionization emission lines. Absorption systems identified at zabs = 1.78, 1.71, and 1.68 show mild oversolar metallicities (Z ~= 1-2Zsolar) and can be attributed t

  3. W. H. T. Vlemmings, H. J. van Langevelde

    The changes in the spectral line profile of the 22GHz H2O maser are calculated as a function of emerging maser flux. We address not only the narrowing and re-broadening of the maser lines, but also the deviations of Gaussian symmetry as a result of the various hyperfine components of the 22 GHz maser line. Non-LTE models of the H2O maser transition, includin

  4. David M. Rothstein, Stephen S. Eikenberry, Keith Matthews

    We present evidence that ~ 30 minute episodes of jet formation in the Galactic microquasar GRS 1915+105 may sometimes entirely be a superposition of smaller, faster phenomena. We base this conclusion on simultaneous X-ray and infrared observations in July 2002, using the Rossi X-ray Timing Explorer and the Palomar 5 meter telescope. On two nights, we observe

  5. J. K. Jorgensen, F. L. Schoeier, E. F. van Dishoeck

    Radiative transfer models of multi-transition observations are used to determine molecular abundances as functions of position in pre- and protostellar cores. The data require a "drop" abundance profile with radius, with high abundances in the outermost regions probed by low excitation 3 mm lines, and much lower abundances at intermediate zones probe

  6. Miguel A. de Avillez, Dieter Breitschwerdt

    The Local Bubble (LB) is an X-ray emitting region extending 100 pc in radius in the Galactic plane and 300 pc perpendicular to it, and it is embedded in a somewhat larger H{\sc i} deficient cavity. Its origin and spectral properties in UV, EUV and X-rays are still poorly understood. We have performed 3D high resolution (down to 1.25 pc) hydrodynamic superbub

  7. Klaus Halterman, Merle Elson, Surendra Singh

    We compute the electromagnetic response and corresponding forces between two silver nanowires. The wires are illuminated by a plane wave which has the electric field vector perpendicular to the axis of the wires, insuring that plasmonic resonances can be excited. We consider a nontrivial square cross section geometry that has dimensions on the order of $0.1

  8. L. M. Feher, B. Komuves

    In this paper we derive closed formulas for the Thom polynomials of two families of second order Thom-Boardman singularities Σ^{i,j}. The formulas are given as linear combinations of Schur polynomials, and all coefficients are nonnegative.

  9. A. Dekel, F. Stoehr, G. A. Mamon, T. J. Cox

    There is strong evidence that the mass in the Universe is dominated by dark matter, which exerts gravitational attraction but whose exact nature is unknown. In particular, all galaxies are believed to be embedded in massive haloes of dark matter. This view has recently been challenged by surprisingly low random stellar velocities in the outskirts of ordinary

  10. D. B. Leinweber, A. W. Thomas, R. D. Young

    Resummation of the chiral expansion is necessary to make accurate contact with current lattice simulation results of full QCD. Resummation techniques including relativistic formulations of chiral effective field theory and finite-range regularization (FRR) techniques are reviewed, with an emphasis on using lattice simulation results to constrain the paramete

  11. Carlos O. Lousto

    Perturbation theory of rotating black holes is described in terms of the Weyl scalars $ψ_4$ and $ψ_0$; each satisfying the Teukolsky's complex master wave equation with spin $s=\mp2$, and respectively representing outgoing and ingoing radiation. We explicitly construct the metric perturbations out of these Weyl scalars in the Regge-Wheeler gauge in the n

  12. M. Loewe, C. Villavicencio

    Isospin density and thermal corrections for several condensates are discussed, at the one-loop level, in the frame of chiral dynamics with pionic degrees of freedom. The evolution of such objects give an additional insight into the condensed-pion phase transition, that occurs basically when $|\mui|>m_π$, being $|\mui|$ the isospin chemical potential. Calcula

  13. Ehud Altman, Ashvin Vishwanath

    We describe and justify a simple model for the dynamics associated with rapid sweeps across a Feshbach resonance, from the atomic to the molecular side, in an ultra cold Fermi system. The model allows us to relate the observed molecule momentum distribution, including its dependence on the sweep rate, to equilibrium properties of the initial state. For initi

  14. I. Arad, P. H. Johansson

    Using N-body simulations with a large set of massless test particles we compare the predictions of two theories of violent relaxation, the well known Lynden-Bell theory and the more recent theory by Nakamura. We derive ``weaken'' versions of both theories in which we use the whole equilibrium coarse-grained distribution function as a constraint inste

  15. B. L. T. Plourde, T. L. Robertson, P. A. Reichardt, T. Hime

    We report measurements on two superconducting flux qubits coupled to a readout Superconducting QUantum Interference Device (SQUID). Two on-chip flux bias lines allow independent flux control of any two of the three elements, as illustrated by a two-dimensional qubit flux map. The application of microwaves yields a frequency-flux dispersion curve for 1- and 2

  16. P. Miocchi, R. Capuzzo Dolcetta, P. Di Matteo, A. Vicari

    The main topic of this paper is the investigation of the modes of interaction of globular clusters (GCs) moving in the inner part of a galaxy. This is tackled by means of high-resolution N-body simulations, whose first results are presented in this article. Our simulations dealt with primordial very massive (order of 10^7 solar masses) GCs that were able to

  17. Ivan Vitev

    Final state medium-induced gluon radiation in ultradense nuclear matter is examined and shown to favor large angle emission when compared to vacuum bremsstrahlung due to the suppression of collinear gluons. Perturbative expression for the contribution of its hadronic fragments to the back-to-back particle correlations is derived. It is found that in the limi

  18. B. Z. Kopeliovich, J. Nemchik, I. K. Potashnikova, M. B. Johnson

    Recent measurements by the BRAHMS collaboration of high-pT hadron production at forward rapidities at RHIC found the relative production rate(d-Au)/(p-p) to be suppressed, rather than enhanced. Examining other known reactions (forward production of light hadrons, the Drell-Yan process, heavy flavor production, etc.), one notes that all of these display a sim

  19. Florian Pfender

    We present an extension of the Delsarte linear programming method. For several dimensions it yields improved upper bounds for kissing numbers and for spherical codes. Musin's recent work on kissing numbers in dimensions three and four can be viewed in our framework.

  20. N. Ivanova, F. A. Rasio, J. C. Lombardi,, K. L. Dooley

    Bright, ultracompact X-ray binaries observed in dense star clusters, such as Galactic globular clusters, must have formed relatively recently, since their lifetimes as persistent bright sources are short (e.g., ~10^8 yr above 10^36 erg/s for a 1.4 Msun neutron star accreting from a degenerate helium companion with an initial mass of ~0.2 Msun). Therefore, we

  21. Johannes Kerimo

    We obtain the pp-waves of D=5 and D=4 gauged supergravities supported by $U(1)^3$ and $U(1)^4$ gauge field strengths respectively. We show that generically these solutions preserve 1/4 of the supersymmetry, but supernumerary supersymmetry can arise for appropriately constrained harmonic functions associated with the pp-waves. In particular it implies that th

  22. M. Melis, S. Mignemi

    We study the phase space of the spherically symmetric solutions of Einstein Gauss-Bonnet system nonminimally coupled to a scalar field and show that in four dimensions the only regular black hole solutions are asymptotically flat

  23. N. Bartolo, S. Matarrese, A. Riotto

    We discuss how primordial (e.g. inflationary) non-Gaussianity in the cosmological perturbations is left imprinted in the Large-Scale Structure of the universe. Our findings show that the information on the primordial non-Gaussianity set on super-Hubble scales flows into Post-Newtonian terms, leaving an observable imprint in the Large-Scale Structure. Future

  24. Michele Caselle, Martin Hasenbusch, Marco Panero

    We discuss a way to evaluate the full prediction for the interquark potential which is expected from the effective Nambu-Goto string model. We check the correctness of the prescription reproducing the results obtained with the zeta function regularization for the first two perturbative orders. We compare the predictions with existing Monte Carlo data for the

  25. F. Pont, C. H. F. Melo, F. Bouchy, S. Udry

    We report the discovery and characterisation of OGLE-TR-122b, the smallest main-sequence star to date with a direct radius determination. OGLE-TR-122b transits around its solar-type primary every 7.3-days. With M=0.092+-0.009 Mo and R=0.120 +0.024-0.013 Ro, it is by far the smallest known eclipsing M-dwarf. The derived mass and radius for OGLE-TR-122b are in

  26. Arne Brataas, Yaroslav Tserkovnyak, Gerrit E. W. Bauer

    The mode dependence of current-induced magnetic excitations in spin valves is studied theoretically. The torque exerted on the magnetization by transverse spin currents as well as the Gilbert damping constant are found to depend strongly on the wave length of the excitation (spin wave). Analytic expressions are presented for the critical currents that excite

  27. B. König, E. W. Guenther, J. Woitas, A. P. Hatzes

    EK Dra (HD 129333) is a young, active, nearby star that is orbited by a low mass companion. By combining new speckle observations with old and new radial velocity measurements we find that the orbit is highly eccentric with e=0.82\pm0.03, and we derive the true masses of both components. The masses are $0.9\pm0.1 {\rm M}_\odot$ and $0.5\pm0.1 {\rm M}_\odot$,

  28. Jean-Philippe Bouchaud, Giulio Biroli

    We argue that for generic systems close to a critical point, an extended Fluctuation-Dissipation relation connects the low frequency non-linear (cubic) susceptibility to the four-point correlation function. In glassy systems, the latter contains interesting information on the heterogeneity and cooperativity of the dynamics. Our result suggests that if the ab

  29. Eduardo Guendelman, Alexander Kaganovich, Emil Nissimov, Svetlana Pacheva

    We discuss in some detail the properties of a novel class of Weyl-conformally invariant p-brane theories which describe intrinsically light-like branes for any odd world-volume dimension and whose dynamics significantly differs from that of the ordinary (conformally non-invariant) Nambu-Goto p-branes. We present explicit solutions of the WILL-brane (Weyl-Inv

  30. Richard L. White, Robert H. Becker, David J. Helfand

    Archival data have been combined with recent observations of the Galactic plane using the Very Large Array to create new catalogs of compact centimetric radio sources. The 20 cm source catalog covers a longitude range of -20 deg < l < 120 deg; the latitude coverage varies from +- 0.8 deg to +- 2.7 deg. The total survey area is ~331 sq deg; coverage is 90% co

  31. Kevin A. Parendo, K. H. Sarwa B. Tan, A. Bhattacharya, M. Eblen-Zayas

    Superconductivity has been induced in insulating ultra-thin films of amorphous bismuth using the electric field effect. The screening of electron-electron interaction was found to increase with electron concentration in a manner correlated with the tendency towards superconductivity. This does not preclude an increase in the density of states being important

  32. T. Repolust, J. Puls, M. M. Hanson, R. -P. Kudritzki

    In this paper we have analyzed 25 Galactic O and early B-stars by means of H and K band spectroscopy, with the primary goal to investigate to what extent a lone near-IR spectroscopy is able to recover stellar and wind parameters derived in the optical. Most of the spectra have been taken with SUBARU IRCS, at a resolution of 12,000, and with a very high S/N (

  33. Dimitri Polyakov

    We discuss the appearance of the GL(1) charged physical operators in the twistor string theory. These operators are shown to be BRST-invariant and non-trivial, and some of their correlators and conformal beta-functions are computed. Remarkably, the non-conservation of the GL(1)-charge in interactions involving these operators is related to the anomalous term

  34. Patrick N. McGraw, Michael Menzinger

    Using a recently described technique for manipulating the clustering coefficient of a network without changing its degree distribution, we examine the effect of clustering on the synchronization of phase oscillators on networks with Poisson and scale-free degree distributions. For both types of network, increased clustering hinders global synchronization as

  35. K. Galsgaard, C. E. Parnell

    The magnetic field plays a crucial role in heating the solar corona, but the exact energy release mechanism(s) is(are) still unknown. Here, we investigate in detail, the process of magnetic energy release in a situation where two initially independent flux systems are forced into each other. Work done by the foot point motions goes in to building a current s

  36. A. Ilderton

    Properties of Green&#39;s functions may be derived in either first or second quantisation. We illustrate this with a factorisation property for propagators in arbitrary spacetimes, and apply it to scalar fields in AdS space.

  37. Alberto De Gregorio

    This paper deals with the Physics Institute of via Panisperna in Rome, getting ready for investigation on neutron physics before Fermi&#39;s discovery of neutron-induced radioactivity. The importance of nuclear research had been acknowledged in the Physics Institute in Rome since 1929. The Institute had been directed towards nuclear physics since then, but f

  38. Sergiu I. Vacaru

    We propose a new framework for constructing geometric and physical models on nonholonomic manifolds provided both with Clifford -- Lie algebroid symmetry and nonlinear connection structure. Explicit parametrizations of generic off-diagonal metrics and linear and nonlinear connections define different types of Finsler, Lagrange and/or Riemann-Cartan spaces. A

  39. Ulrich Bunke, Philipp Rumpf, Thomas Schick

    In string theory, the concept of T-duality between two principal T^n-bundles E_1 and E_2 over the same base space B, together with cohomology classes h_1\in H^3(E_1) and h_2\in H^3(E_2), has been introduced. One of the main virtues of T-duality is that h_1-twisted K-theory of E_1 is isomorphic to h_2-twisted K-theory of E_2. In this paper, a new, very topolo

  40. W. -Y. Hwang

    The Ekert 91 quantum key distribution (QKD) protocol appears to be secure whatever devices legitimate users adopt for the protocol, as long as the devices give a result that violates Bell&#39;s inequality. However, this is not the case if they ignore non-detection events because Eve can make use of the detection-loophole, as Larrson showed. We show that even

  41. Ki-Seok Kim

    We investigate the effect of nonmagnetic disorder on the stability of the algebraic spin liquid ($ASL$) by deriving an effective field theory, nonlinear $σ$ model ($NLσM$). We find that the anomalous critical exponent characterizing the criticality of the $ASL$ causes an anomalous gradient in the $NLσM$. We show that the sign of the anomalous gradient expone

  42. Masaki Ishii, Masaru Shibata, Yasushi Mino

    We derive a tidal potential for a self-gravitating fluid star orbiting Kerr black hole along a timelike geodesic extending previous works by Fishbone and Marck. In this paper, the tidal potential is calculated up to the third and fourth-order terms in $R/r$, where $R$ is the stellar radius and $r$ the orbital separation, in the Fermi-normal coordinate system

  43. L. Stawarz, A. Siemiginowska, M. Ostrowski, M. Sikora

    Several low-power kiloparsec-scale jets in nearby radio galaxies are known for their synchrotron radiation extending up to optical and X-ray photon energies. Here we comment on high-energy gamma-ray emission of one particular object of this kind, i.e. the kiloparsec-scale jet of M 87 radio galaxy, resulting from comptonization of the starlight photon field o

  44. Mustapha Ishak

    We study future constraints on dark energy parameters determined from several combinations of CMB experiments, supernova data, and weak lensing surveys with and without tomography. In this analysis, we look in particular for combinations that will bring the uncertainties to a level of precision tight enough (a few percent) to answer decisively some of the da

  45. Hai-Yang Cheng, Kwei-Chou Yang

    The decay $B\to f_0(980)K is studied within the framework of QCD factorization and the two-quark scenario for $f_0(980)$. There are two distinct penguin contributions and their interference depends on the unknown mixing angle $θ$ of strange and nonstrange quark contents of $f_0(980)$: destructive for $0<θ<π/2$ and constructive for $π/2<θ<π$. The QCD sum rule

  46. Dao-jun Liu, Xin-zhou Li

    The cosmological dynamics of minimally coupled scalar field that couple to the background matter with thermal interactions is investigated in exponential potential. The conditions for the existence and stability of various critical points as well as their cosmological implications are obtained. Although we show that the effects of thermal interaction such as

  47. M. Dine, D. O&#39;Neil, Z. Sun

    With respect to the question of supersymmetry breaking, there are three branches of the flux landscape. On one of these, if one requires small cosmological constant, supersymmetry breaking is predominantly at the fundamental scale; on another, the distribution is roughly flat on a logarithmic scale; on the third, the preponderance of vacua are at very low sc

  48. Taesoo Song, Su Houng Lee

    The next to leading order (NLO) quarkonium-hadron cross section is calculated in perturbative QCD. The corresponding leading order (LO) result was performed by Peskin more than 20 years ago using the operator product expansion (OPE). In this work, the calculation is performed using the Bethe-Salpeter amplitude and the factorization formula. The soft divergen

  49. Stuart E. Brown, Eduardo Fradkin, Steven A. Kivelson

    We study the mean-field theory of charge-density wave (CDW) order in a layered system, including the effect of the long-range Coulomb interaction and of screening by uncondensed electrons. We particularly focus on the conditions necessary for an ``extraordinary&#39;&#39; transition, in which the surface orders at a higher temperature, and is more likely to b

  50. Ö. E. Müstecaplıoğlu, M. Zhang, L. You

    We study quantum dynamical properties of a spin-1 atomic Bose-Einstein condensate in a double-well potential. Adopting a mean field theory and single spatial mode approximation, we characterize our model system as two coupled spins. For certain initial states, we find full magnetization oscillations between wells not accompanied by mass (or atom numbers) exc

  51. Frank Vewinger, Frank Zimmer

    We report the observation of transient velocity-selective coherent population trapping (VSCPT) in a beam of metastable neon atoms. The atomic momentum distribution resulting from the interaction with counterpropagating sigma_+ and sigma_- radiation which couples a J_g=2 <-> J_e=1 transition is measured via the transversal beam profile. This transition exhibi

  52. Dariusz Chruscinski, Krzysztof Mlodawski

    We discuss a family of quasi-distributions (s-ordered Wigner functions of Agarwal and Wolf) and its connection to the so called phase space representation of the Schroedinger equation. It turns out that although Wigner functions satisfy the Schroedinger equation in phase space they have completely different interpretation.

  53. Tulsi Dass

    These lecture notes cover the important developments in histories approach to quantum mechanics with overall content and emphasis somewhat different from other reviews and books on the subject.The idea of Houtappel, Van Dam and Wigner of employing objects based on primitive concepts of physical theories is discussed in some detail and the fact that histories

  54. Wim van Dam

    This Letter looks at the consequences of so-called &#39;superstrong nonlocal correlations&#39;, which are hypothetical violations of Bell/CHSH inequalities that are stronger than quantum mechanics allows, yet weak enough to prohibit faster-than-light communication. It is shown that the existence of maximally superstrong correlated bits implies that all distr

  55. Madalena Chaves, Reka Albert, Eduardo D. Sontag

    Interactions between genes and gene products give rise to complex circuits that enable cells to process information and respond to external signals. Theoretical studies often describe these interactions using continuous, stochastic, or logical approaches. We propose a new modeling framework for gene regulatory networks, that combines the intuitive appeal of

  56. G. Van Hooydonk

    Molecular band spectra as well as atomic line spectra reveal a left-right symmetry for atoms (Van Hooydonk, Spectrochim. Acta A, 2000, 56, 2273 and Phys. Rev. A 66, 044103 (2002). We now extract a Mexican hat shaped or double well curve from the line spectrum (Lyman ns-series) of natural atom H. An H CSB theory and its oscillator contribution (1-0.5pi/n)sup(

  57. G. Van Hooydonk

    Molecular band spectra reveal a left-right symmetry for atoms (Van Hooydonk, Spectrochim.Acta A, 2000, 56, 2273). Intra-atomic left-right symmetry points to antiatom states and, to make sense, this must also show in line spectra. H Lyman ns-states show a mirror plane at quantum number n=pi/2. Symmetry breaking oscillator (1-0.5pi/n)sup(2) means that some of

  58. Jacob Scheuer, William M. J. Green, Guy A. DeRose, Amnon Yariv

    A novel class of circular resonators, based on a radial defect surrounded by Bragg reflectors, is studied in detail. Simple rules for the design and analysis of such structures are derived using a transfer matrix formalism. Unlike conventional ring resonators, annular Bragg resonators (ABR) are not limited by the total internal reflection condition, and can

  59. Guy Bartal, Oren Cohen, Hrvoje Buljan, Jason W. Fleischer

    We present a novel, real-time, experimental technique for linear and nonlinear Brillouin zone spectroscopy of photonic lattices. The method relies on excitation with random-phase waves and far-field visualization of the spatial spectrum of the light exiting the lattice. Our technique facilitates mapping the borders of the extended Brillouin zones and the are

  60. Taehyun Kim, Marco Fiorentino, Pavel V. Gorelik, Franco N. C. Wong

    We present a simple and low-cost implementation of a fast electronic coincidence detector based on PECL logic with a TTL-compatible interface. The detector has negligible dead time and the coincidence window is adjustable with a minimum width of 1 ns. Coincidence measurements of two independent sources of Bose-Einstein distributed photocounts are presented u

  61. Jagmeet Singh, K. Subramanyam

    Two filter based approaches for deghosting of Ocean Bottom Cable data are presented. One of them is phase shifting of geophone followed by least square matching of cross ghosted geophone and hydrophone data.In the second approach,phase shifting of geophone is followed by direct matching of geophone&#39;s amplitude spectrum with that of the hydrophone within

  62. C. Barbieri, B. K. Jennings

    Feshbach&#39;s projection formalism in the particle-hole model space leads to a microscopic description of scattering in terms of the many-body self-energy. To investigate the feasibility of this approach, an optical potential for O-16 is constructed starting from two previous calculations of the self-energy for this nucleus. The results reproduce the backgr

  63. H. Nemura, S. Shinmura, Y. Akaishi, Khin Swe Myint

    We describe full-coupled-channel ab initio calculations among the octet baryons for S=-2 s-shell hypernuclei,_{LambdaLambda}^4H,_{LambdaLambda}^5H and_{LambdaLambda}^6He. The wave function includes Lambda Lambda, Lambda Sigma, N Xi, and Sigma Sigma channels. Minnesota NN, D2^\prime YN and Nijmegen model D simulated YY interactions are used. This is the first

  64. Y. M. Zhao, A. Arima

    In this paper we study the enumeration of number (denoted as ${D_I}$) of spin $I$ states for fermions in a single-$j$ shell and bosons with spin $l$. We show that $D_I$ can be enumerated by the reduction from SU$(n+1)$ to SO(3). New regularities of $D_I$ are discerned.

  65. Alan Edelman, Per-Olof Persson

    We present efficient numerical techniques for calculation of eigenvalue distributions of random matrices in the beta-ensembles. We compute histograms using direct simulations on very large matrices, by using tridiagonal matrices with appropriate simplifications. The distributions are also obtained by numerical solution of the Painleve II and V equations with

  66. Pavel Exner

    We consider a class of Hamiltonians in $L^2(\R^2)$ with attractive interaction supported by piecewise $C^2$ smooth loops $Γ$ of a fixed length $L$, formally given by $-Δ-αδ(x-Γ)$ with $α>0$. It is shown that the ground state of this operator is locally maximized by a circular $Γ$. We also conjecture that this property holds globally and show that the problem

  67. Michael Kleber

    This &#34;Mathematical Entertainments&#34; column from the Intelligencer is an exposition of current investigations, rooted in recent work of Jim Propp, into &#34;quasirandom&#34; analogues of random walk and random aggregation processes. Featured are the &#34;Goldbugs&#34; and the &#34;Rotor-router&#34;. These are deterministic processes which simulate the

  68. Marius Dadarlat, Erik Guentner

    Let $Γ$ be a finitely generated group which is hyperbolic relative to a finite family $\{H_1,...,H_n\}$ of subgroups. We prove that $Γ$ is uniformly embeddable in a Hilbert space if and only if each subgroup $H_i$ is uniformly embeddable in a Hilbert space.

  69. Charles F. Dunkl

    For certain negative rational numbers k0, called singular values, and associated with the symmetric group S_N on N objects, there exist homogeneous polynomials annihilated by each Dunkl operator when the parameter k = k0. It was shown by de Jeu, Opdam and the author (TAMS 346(1994),237-256) that the singular values are exactly the values m/n with 2<=n<=N, m

  70. Adela N. Comanici

    We study non-resonant and resonant Hopf bifurcation of a rotating wave in SO(3)-equivariant reaction-diffusion systems on a sphere. We obtained reduced differential equations on so(3), the characterization of modulated rotating waves obtained by Hopf bifurcation of a rotating wave, as well as results regarding the resonant case. Our main tools are the equiva

  71. Alex Kuronya

    In this paper we define certain analogues of the volume of a divisor - called asymptotic cohomological functions - and investigate their behaviour on the Neron--Severi space. We establish that asymptotic cohomological functions are invariant with respect to the numerical equivalence of divisors, and that they give rise to continuous functions on the real Ner

  72. J. Scott Carter, Mohamed Elhamdadi, Masahico Saito, Shin Satoh

    We study the number of Reidemeister type III moves using Fox n-colorings of knot diagrams.

  73. Aramyan Rafik

    In this article we pose the problem of existence and uniqueness of convex body for which the projection curvature radius function coincides with given function. We find a necessary and sufficient condition that ensures a positive answer to both questions and suggest an algorithm of construction of the body. Also we find a representation of the support functi

  74. Krzysztof Burdzy, Zhen-Qing Chen, Peter Jones

    For every bounded planar domain $D$ with a smooth boundary, we define a `Lyapunov exponent&#39; $Λ(D)$ using a fairly explicit formula. We consider two reflected Brownian motions in $D$, driven by the same Brownian motion (i.e., a `synchronous coupling&#39;). If $Λ(D)>0$ then the distance between the two Brownian particles goes to 0 exponentially fast with r

  75. Sever Silvestru Dragomir

    Some genearlizations of Precupanu&#39;s inequality for orthornormal families of vectors in real or complex inner product spaces and applications related to Buzano&#39;s, Richard&#39;s and Kurepa&#39;s results are given

  76. Roland W. Freund

    A standard approach to model reduction of large-scale higher-order linear dynamical systems is to rewrite the system as an equivalent first-order system and then employ Krylov-subspace techniques for model reduction of first-order systems. This paper presents some results about the structure of the block-Krylov subspaces induced by the matrices of such equiv

  77. Raf Bocklandt, Stijn Symens, Geert Van de Weyer

    Given a Cayley-Hamilton smooth order A in a central simple algebra $Σ$, we determine the flat locus of the Brauer-Severi fibration of the smooth order. Moreover, we give a classification of all (reduced) central singularities where the flat locus differs from the Azumaya locus and show that the fibers over the flat, non-Azumaya points near these central sing

  78. N. Burq, P. Gerard, N. Tzvetkov

    We study nonlinear Schrödinger equations, posed on a three dimensional Riemannian manifold $M$. We prove global existence of strong $H^1$ solutions on $M=S^3$ and $M=S^2\times S^1$ as far as the nonlinearity is defocusing and sub-quintic and thus we extend the results of Ginibre-Velo and Bourgain who treated the cases of the Euclidean space $\R^3$ and the fl

  79. Holger Brenner

    Let I denote an R_+ -primary homogeneous ideal in a normal standard-graded Cohen-Macaulay domain over a field of positive characteristic p. We give a linear degree bound for the Frobenius powers I^[q] of I, q=p^e, in terms of the minimal slope of the top-dimensional syzygy bundle on the projective variety Proj R. This provides an inclusion bound for tight cl

  80. Ger Koole, Misja Nuyens, Rhonda Righter

    We study the impact of service-time distributions on the distribution of the maximum queue length during a busy period for the M^X/G/1 queue. The maximum queue length is an important random variable to understand when designing the buffer size for finite buffer (M/G/1/n) systems. We show the somewhat surprising result that for three variations of the preempt

  81. Yves Stalder

    We study convergent sequences of Baumslag-Solitar groups in the space of marked groups. We prove that BS(m,n) --> F_2 for |m|,|n| --> \infty and BS(1,n) --> Z \wr Z for |n| --> \infty. For m fixed, |m|>1, we show that the sequence (BS(m,n))_n is not convergent and characterize many convergent subsequences. Moreover if X_m is the set of BS(m,n)&#39;s for n re

  82. Isabel Fernandez, Francisco J. Lopez, Rabah Souam

    We show that a complete embedded maximal surface in the 3-dimensional Lorentz-Minkowski space $L^3$ with a finite number of singularities is, up to a Lorentzian isometry, an entire graph over any spacelike plane asymptotic to a vertical half catenoid or a horizontal plane and with conelike singular points. We study the space $G_n$ of entire maximal graphs ov

  83. Erik Kramer

    Various ideas support the notion that the GUT gauge group might be a semi-simple direct-product group such as $SU(5) \times SU(5)$. The doublet-triplet splitting problem can be solved with a direct product group. String theory suggests that the GUT scale is a modulus. Requiring this rules out a single SU(5) gauge group. A model with $SU(5) \times SU(5)$ gaug

  84. Matej Pavsic

    The idea that spacetime has to be replaced by Clifford space (C-space) is explored. Quantum field theory (QFT) and string theory are generalized to C-space. It is shown how one can solve the cosmological constant problem and formulate string theory without central terms in the Virasoro algebra by exploiting the peculiar pseudo-Euclidean signature of C-space

  85. Velimir Bardek, Stjepan Meljanac

    We consider a large $- N, $ two-family Calogero model in the Hamiltonian, collective-field approach. The Bogomol&#39;nyi limit appears and the corresponding solutions are given by the static-soliton configurations. Solitons from different families are localized at the same place. They behave like a paired hole and lump on the top of the uniform vacuum conden

  86. Marek Rogatko

    We derive formulas for variations of mass, angular momentum and canonical energy in Einstein (n-2)-gauge form field theory by means of the ADM formalism. Considering the initial data for the manifold with an interior boundary which has the topology of (n-2)-sphere we obtained the generalized first law of black hole thermodynamics. Supposing that a black hole

  87. S. A. Alavi

    We study the spectrum of Hydrogen atom, Lamb shift and Stark effect in the framework of simultaneous space-space and momentum-momentum (s-s, p-p) noncommutative quantum mechanics. The results show that the widths of Lamb shift due to noncommutativity is bigger than the one presented in [1]. We also study the algebras of abservables of systems of identical pa

  88. Daniele Binosi, Joannis Papavassiliou, Apostolos Pilaftsis

    We present a new method for determining the renormalization of Green functions to all orders in perturbation theory, which we call the displacement operator formalism, or the D-formalism, in short. This formalism exploits the fact that the renormalized Green functions may be calculated by displacing by an infinite amount the renormalized fields and parameter

  89. Daniel de Florian, Werner Vogelsang

    We study the resummation of large logarithmic perturbative corrections to the partonic cross sections relevant for the process pp->h X at high transverse momentum of the hadron h. These corrections arise near the threshold for the partonic reaction and are associated with soft-gluon emission. We perform the resummation to next-to-leading logarithmic accuracy

  90. Einan Gardi

    I present new results on the quark distribution in an on-shell heavy quark in perturbative QCD and explore its all-order relations with heavy-quark fragmentation. I first compute the momentum distribution function to all orders in the large-beta_0 limit and show that it is identical to the perturbative heavy-quark fragmentation function in the same approxima

  91. Rohini M. Godbole

    In this talk I explain in brief the motivations behind undertaking a study of the LHC-ILC interplay. I will give information about the activities of the LHC-LC study group as well as the study group document. I will illustrate the scope of the document by taking a few examples from the document which has appeared on the archives \cite{Group:2004hn} since thi

  92. K. -I. Izawa, T. Yanagida

    A model of gauge mediation with the gravitino mass of order 1eV is considered to motivate 100TeV colliders. Massive mediators with standard-model and supersymmetry-breaking gauge quantum numbers let low-scale dynamics induce sizable soft masses of the standard-model superpartners. We circumvent potential phenomenological difficulties that such low-scale mode

  93. Catherine I. Low

    I construct predictive models of neutrino mass and mixing that have fewer parameters, both in the lepton sector and overall, than the default seesaw model. The predictions are theta13=0 and one massless neutrino, with the models having a Z4 or Z2 symmetry and just one extra degree of freedom: one real singlet Higgs field. It has been shown that models with a

  94. S. V. Goloskokov

    Vector meson electroproduction is analyzed within the two-gluon (2G) model and the generalized parton distribution (GPD) approach at small $x$-Bjorken. We demonstrate that 2G and GPD models are not completely equivalent. At the same time, both models are in reasonable agreement with available experimental data on light vector meson electroproduction.

  95. K. Hayasaka

    We have searched for the lepton-flavor-violating decay tau -> e gamma using a data sample of 86.7/fb collected with the Belle detector at the KEKB asymmetric e^+ e^- collider. No evidence for a signal is obtained, and we set an upper limit for the branching fraction Br(tau -> e gamma) < 3.9 x 10^-7 at the 90% C.L.

  96. Alex Melnitchouk

    A search for non-SM light Higgs boson with an enhanced branching fraction into photons in ppbar collisions at the Fermilab Tevatron is presented using Run II DO data taken between April 2002 and September 2003. We set 95% CL limits on the diphoton branching fraction as a function of Higgs mass for Fermiophobic and Topcolor Higgs scenarios.

  97. Adrian C. Melissinos, William E. Butler

    Laser interferometer gravitational wave detectors can be operated at their free spectral range frequency. We show that in this case and when the interferometer is well understood one could detect a stochastic background using a single detector.

  98. Masato Minamitsuji, Misao Sasaki, David Langlois

    We discuss the effect of Kaluza-Klein (KK) modes of bulk metric perturbations on the second Randall-Sundrum (RS II) type brane cosmology, taking the possible backreaction in the bulk and on the brane into account. KK gravitons may be produced via quantum fluctuations during a de Sitter (dS) inflating phase of our brane universe. In an effective 4-dimensional

  99. Zengyou He, Xiaofei Xu, Shengchun Deng

    The data mining process consists of a series of steps ranging from data cleaning, data selection and transformation, to pattern evaluation and visualization. One of the central problems in data mining is to make the mined patterns or knowledge actionable. Here, the term actionable refers to the mined patterns suggest concrete and profitable actions to the de

  100. X. P. A. Gao, G. S. Boebinger, A. P. Mills, A. P. Ramirez

    We have studied the temperature dependent phonon emission rate $P$($T$) of a strongly interacting ($r_s\geq$22) dilute 2D GaAs hole system using a standard carrier heating technique. In the still poorly understood metallic state, we observe that $P$($T$) changes from $P$($T$)$\sim T^5$ to $P$($T$)$\sim T^7$ above 100mK, indicating a crossover from screened p