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November 2007 arXiv papers — page 22

Showing 2,1012,200 of 5,016 papers

  1. Kazuhiro Hikami, Hitoshi Murakami

    The volume conjecture and its generalizations say that the colored Jones polynomial corresponding to the N-dimensional irreducible representation of sl(2;C) of a (hyperbolic) knot evaluated at exp(c/N) grows exponentially with respect to N if one fixes a complex number c near 2*Pi*I. On the other hand if the absolute value of c is small enough, it converges

  2. Charles Favre, Mattias Jonsson

    We find good dynamical compactifications for arbitrary polynomial mappings of C^2 and use them to show that the degree growth sequence satisfies a linear integral recursion formula. For maps of low topological degree we prove that the Green function is well behaved. For maps of maximum topological degree, we give normal forms.

  3. A. G. Oganesian

    The moments of the heavy quark-parton distribution functions in a heavy pseudoscalar meson are calculated from QCD sum rules. Expanding these sum rules in the inverse heavy quark mass we obtain the heavy-mass limits of the moments. Comparison with the finite mass results reveals that while the heavy mass expansion works reasonably well for the $b$ quark, one

  4. J. Luis Miramontes

    The Homogeneous sine-Gordon (HSG) theories are integrable perturbations of $G_k/U(1)^{r_G}$ coset CFTs, where $G$ is a simple compact Lie group of rank $r_G$ and $k>1$ is an integer. Using their T-duality symmetries, we investigate the relationship between the different theories corresponding to a given coset, and between the different phases of a particular

  5. Dang Duc Trong, Truong Trung Tuyen

    In this paper we shall consider the growth at infinity of a sequence $(P_n)$ of entire functions of bounded orders. Our results extend the results in \cite{trong-tuyen2} for the growth of entire functions of genus zero. Given a sequence of entire functions of bounded orders $P_n(z)$, we found a nearly optimal condition, given in terms of zeros of $P_n$, for

  6. Lajos Diósi

    We are discussing a universal non-unitary map M subsequent to a generic unitary map U, whose von Neumann entropy gain coincides with the calculated thermodynamic entropy production. For many-body quantum reservoirs we prove that M can be the averaging over all translations of the spatial frame. Assuming the coincidence of microscopic and macroscopic entropy

  7. Alan Dow, Saharon Shelah

    A point x is a (bow) tie-point of a space X if X setminus {x} can be partitioned into (relatively) clopen sets each with x in its closure. Tie-points have appeared in the construction of non-trivial autohomeomorphisms of betaN setminus N= N^* and in the recent study of (precisely) 2-to-1 maps on N^*. In these cases the tie-points have been the unique fixed p

  8. Alan Dow, Saharon Shelah

    A point x is a (bow) tie-point of a space X if X setminus {x} can be partitioned into (relatively) clopen sets each with x in its closure. Tie-points have appeared in the construction of non-trivial autohomeomorphisms of betaN setminus N and in the recent study of (precisely) 2-to-1 maps on betaN setminus N . In these cases the tie-points have been the uniqu

  9. Francisco M. Fernandez

    We calculate accurate bound states and resonances of two interesting perturbed Coulomb models by means of the Riccati-Padé method. This approach is based on a rational approximation to a modified logarithmic derivative of the eigenfunction and produces sequences of roots of Hankel determinants that converge towards the eigenvalues of the equation.

  10. Eleonora Troja, Andrew R. King, Paul T. O'Brien, Nicola Lyons

    We consider the spatial offsets of short hard gamma-ray bursts (SHBs) from their host galaxies. We show that all SHBs with extended duration soft emission components lie very close to their hosts. We suggest that NS-BH binary mergers offer a natural explanation for the properties of this extended duration/low offset group. SHBs with large offsets have no obs

  11. A. A. Moiseev, E. A. Baltz, J. F. Ormes, L. G. Titarchuk

    We present here the prospects for the GLAST Large Area Telescope (LAT) detection of the signature of the lightest Kaluza-Klein particle (LKP). It decays by direct annihilation into electron-positron pairs that may be detectable in the high energy electron flux. We discuss the LAT capability for detecting the high energy (20 GeV - ~1 TeV) cosmic ray electron

  12. Andreas Blass, Saharon Shelah

    We construct a non-free but aleph_1-separable, torsion-free abelian group G with a pure free subgroup B such that all subgroups of G disjoint from B are free and such that G/B is divisible. This answers a question of Irwin and shows that a theorem of Blass and Irwin cannot be strengthened so as to give an exact analog for torsion-free groups of a result prov

  13. Richard Gran

    The MINERvA neutrino interaction experiment in the NuMI beam at Fermilab will measure several aspects of neutrino interactions in the few GeV energy region. We will make cross section and form factor measurements using a fine-grained fully active scintillator (CH) target, and also investigate nuclear effects on neutrino interactions as well as hadron rescatt

  14. O. Benichou, R. Voituriez

    The time needed for a particle to exit a confining domain through a small window, called the narrow escape time (NET), is a limiting factor of various processes, such as some biochemical reactions in cells. Obtaining an estimate of the mean NET for a given geometric environment is therefore a requisite step to quantify the reaction rate constant of such proc

  15. Richard Gran

    This is an exciting time for folks who are looking at neutrino cross sections, and the especially important quasielastic interaction. We are able to inspect several recent results from K2K and MiniBooNE and are looking forward to a couple more high statistics measurements of neutrino and anti-neutrino interactions. There is additional interest because of the

  16. The IceCube Collaboration, M. Ackermann

    A search for diffuse neutrinos with energies in excess of 10^5 GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10^7 GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra high-energy neutrinos at the horizon. The primary

  17. Tridib Sadhu, Deepak Dhar

    We study the Zhang model of sandpile on a one dimensional chain of length $L$, where a random amount of energy is added at a randomly chosen site at each time step. We show that in spite of this randomness in the input energy, the probability distribution function of energy at a site in the steady state is sharply peaked, and the width of the peak decreases

  18. Chia-Ren Hu

    It is shown that, in a conductor carrying a moderate spin current, singlet pairing can still take place almost as effectively as without a spin current. The system will still be fully gapped for all spin-up and -down single-particle excitations, with no depaired electrons. All thermodynamic properties will be practically the same as without the spin current.

  19. M. O. Hase, J. F. F. Mendes

    The question of robustness of a network under random ``attacks'' is treated in the framework of critical phenomena. The persistence of spontaneous magnetization of a ferromagnetic system to the random inclusion of antiferromagnetic interactions is investigated. After examing the static properties of the quenched version (in respect to the random anti

  20. Jun Koda, Milos Milosavljevic, Paul R. Shapiro

    We study the formation of disk-dominated galaxies in a Lambda CDM universe. Their existence is considered to be a challenge for the Lambda CDM cosmology, because galaxy mergers isotropize stellar disks and trigger angular momentum transport in gas disks, thus fostering the formation of central stellar spheroids. Here, we postulate that the formation of stell

  21. Eiko Kin, Mitsuhiko Takasawa

    The dilatation of a pseudo-Anosov braid is a conjugacy invariant. In this paper, we study the dilatation of a special family of pseudo-Anosov braids. We prove an inductive formula to compute their dilatation, a monotonicity and an asymptotic behavior of the dilatation for this family of braids. We also give an example of a family of pseudo-Anosov braids with

  22. Jan Staff, Brian Niebergal, Rachid Ouyed

    We present a three-stage model for a long GRB inner engine to explain the prompt gamma ray emission, and interpret recent Swift satellite observations of early X-ray afterglow plateaus followed by a sharp drop off or a shallow power law decay. The three stages involves a neutron star phase, a quark star (QS) and a black hole phase as described in Staff et al

  23. Kurt Langfeld

    After a brief introduction to the statistical description of data, these lecture notes focus on quantum field theories as they emerge from lattice models in the critical limit. For the simulation of these lattice models, Markov chain Monte-Carlo methods are widely used. We discuss the heat bath and, more modern, cluster algorithms. The Ising model is used as

  24. Georg Weiglein

    Some aspects of electroweak physics at the International Linear Collider (ILC) are reviewed. The importance of precision measurements in the Higgs sector and in top-quark physics is emphasized, and the physics potential of the GigaZ option of the ILC is discussed. It is shown in particular that even in a scenario where the states of new physics are so heavy

  25. G. Aurelio, J. Curiale, R. D. Sanchez, G. J. Cuello

    In this article we study the effects of a partial substitution of Ba with the smaller cation Ca in the layered cobaltites YBaCo_2O_{5+δ} for δ\approx 0.5. Neutron thermodiffractograms are reported for the compounds YBa_{0.95}Ca_{0.05}Co_2O_{5.5} (x_{Ca}=0.05) and YBa_{0.90}Ca_{0.10}Co_2O_{5.5} (x_{Ca}=0.10) in the temperature range 20 K \leq T \leq 300 K, as

  26. Natalia Ivanova, Craig O. Heinke, Frederic A. Rasio

    In this contribution we discuss how neutron stars are produced and retained in globular clusters, outlining the most important dynamical channels and evolutionary events that affect thepopulation of mass-transferring binaries with neutron stars and result in the formation of recycled pulsars. We confirm the importance of electron-capture supernovae in globul

  27. Yannick Frein, Benjamin Lévêque, Andras Sebo

    We consider the problem of minimizing the size of a family of sets G such that every subset of 1,...,n can be written as a disjoint union of at most k members of G, where k and n are given numbers. This problem originates in a real-world application aiming at the diversity of industrial production. At the same time, the minimum of G so that every subset of 1

  28. P. Watson, H. Reinhardt

    It is argued that within the continuum functional formalism, there is no need to supply a further (spatially independent) gauge constraint to complete the Coulomb gauge of Yang-Mills theory. It is shown explicitly that a natural completion of the gauge-fixing leads to a contradiction with the perturbative renormalizability of the theory.

  29. Ryan Requist, Oleg Pankratov

    A system of electrons in a local or nonlocal external potential can be studied with 1-matrix functional theory (1MFT), which is similar to density functional theory (DFT) but takes the one-particle reduced density matrix (1-matrix) instead of the density as its basic variable. Within 1MFT, Gilbert derived [PRB 12, 2111 (1975)] effective single-particle equat

  30. J. Aichelin, H. Petersen, S. Vogel, M. Bleicher

    There is little doubt that Quantumchromodynamics (QCD) is the theory which describes strong interaction physics. Lattice gauge simulations of QCD predict that in the $μ,T$ plane there is a line where a transition from confined hadronic matter to deconfined quarks takes place. The transition is either a cross over (at low $μ$) or of first order (at high $μ$).

  31. H. A. Carmona, F. K. Wittel, F. Kun, H. J. Herrmann

    We study the brittle fragmentation of spheres by using a three-dimensional Discrete Element Model. Large scale computer simulations are performed with a model that consists of agglomerates of many particles, interconnected by beam-truss elements. We focus on the detailed development of the fragmentation process and study several fragmentation mechanisms. The

  32. Jost-Hinrich Eschenburg, Martin Kerin

    Gromoll and Meyer have represented a certain exotic 7-sphere $Σ^7$ as a biquotient of the Lie group $G = Sp(2)$. We show for a 2-parameter family of left invariant metrics on $G$ that the induced metric on $Σ^7$ has strictly positive sectional curvature at all points outside four subvarieties of codimension $\geq 1$ which we describe explicitly.

  33. R. S. Thorne

    I consider the uncertainties in parton distributions and the consequences for hadronic cross-sections. There is ever-increasing sophistication in the relationship between the uncertainties of the distributions and the errors on the experimental data used to extract them. However, I demonstrate that this uncertainty is frequently subsumed by that due to the c

  34. Guido Tiana

    With the help of metadynamics it is possible to calculate efficiently the free energy of systems displaying high energy barriers as a function of few selected "collective variables". In doing this, the contribution of all the other degrees of freedom ("microscopic" variables) is averaged out and, thus, lost. In the following, it is shown that

  35. Antoni Szczurek, Tomasz Pietrycki, Anna Rybarska, Gabriela Slipek

    We discuss correlations in azimuthal angle as well as correlations in two-dimensional space of transverse momenta of two jets as well as photon and jet. Some $k_t$-factorization subprocesses are included for the first time in the literature. Different unintegrated gluon/parton distributions are used in the $k_t$-factorization approach. The results depend on

  36. Remi Tailleux

    The incompressible Navier-Stokes equations currently represent the primary model for describing stratified turbulent fluid flows at low Mach number. The validity of the incompressible assumption, however, has so far only been rigorously established for adiabatic motions. Here, we show from first principl es that the use of available energetics and thermodyna

  37. V. K. Magas, L. P. Csernai

    The freeze out of the expanding systems, created in relativistic heavy ion collisions, is discussed. We combine Bjorken scenario with earlier developed freeze out equations into a unified model. The important feature of the proposed model is that physical freeze out is completely finished in a finite time, which can be varied from 0 (freeze out hypersurface)

  38. Claudio Albanese

    We study triangulation schemes for the joint kernel of a diffusion process with uniformly continuous coefficients and an adapted, non-resonant Abelian process. The prototypical example of Abelian process to which our methods apply is given by stochastic integrals with uniformly continuous coeffcients. The range of applicability includes also a broader class

  39. Brendan Casey

    We discuss several recent measurements of rare charmed hadron decays. Focus is placed on radiative and annihilation topologies highlighting their sensitivity to new physics and pointing out the strengths and weaknesses of different channels. We compare the different measurement techniques employed at fixed target and $e^+e^-$ dedicated charm experiments, B-f

  40. A. C. Fabian

    Iron line emission is common in the X-ray spectra of accreting black holes. When the line emission is broad or variable then it is likely to originate from close to the black hole. X-ray irradiation of the accretion flow by the power-law X-ray continuum produces the X-ray 'reflection' spectrum which includes the iron line. The shape and variability o

  41. G. Guibert, F. Loeser, M. Merle

    We compute the motivic nearby cycles of functions obtained by composition of two functions with distinct sets of variables with a two variable function

  42. Ignazio Licata

    The problem of emergence in physical theories makes necessary to build a general theory of the relationships between the observed system and the observing system. It can be shown that there exists a correspondence between classical systems and computational dynamics according to the Shannon-Turing model. A classical system is an informational closed system w

  43. Jorge E. Fiscina, Christian Wagner

    We investigated the yield stress and the apparent viscosity of sand with and without small amounts of liquid. By pushing the sand through a tube with an enforced Poiseuille like profile we minimize the effect of avalanches and shear localization. We find that the system starts to flow when a critical shear of the order of one particle diameter is exceeded. I

  44. Sylvain Kubicki, Annie Guerriéro, Damien Hanser, Gilles Halin

    In the Architecture Engineering and Construction sector (AEC) cooperation between actors is essential for project success. The configuration of actors' organization takes different forms like the associated coordination mechanisms. Our approach consists in analyzing these coordination mechanisms through the identification of the "base practices"

  45. A. K. Avetissian

    A heuristic hypothesis about domination of Bose-Einstein statistics in the early Universe is suggested. The possibility of Bose-Einstein condensation (BEC) of primordial baryon-antibaryon pairs is considered. In accordance with this postulation enormous masses in the order of galactic mass may be accumulated within the cosmic scales. At the certain threshold

  46. C. Cazorla, J. Boronat

    We study the zero-temperature equation of state (EOS) of solid 4He in the hexagonal closed packet (hcp) phase over the 0-57 GPa pressure range by means of the Diffusion Monte Carlo (DMC) method and the semi-empirical Aziz pair potential HFD-B(HE). In the low pressure regime (P ~ 0-1 GPa) we assess excellent agreement with experiments and we give an accurate

  47. C. Burrage

    Measurements of standard candles and measurements of standard rulers give an inconsistent picture of the history of the universe. This discrepancy can be explained if photon number is not conserved as computations of the luminosity distance must be modified. I show that photon number is not conserved when photons mix with chameleons in the presence of a magn

  48. Yuval Elias, José M. Fernandez, Tal Mor, Yossi Weinstein

    Algorithmic Cooling (AC) of Spins is potentially the first near-future application of quantum computing devices. Straightforward quantum algorithms combined with novel entropy manipulations can result in a method to improve the identification of molecules. We introduce here several new exhaustive cooling algorithms, such as the Tribonacci and k-bonacci algor

  49. Ken Ebisawa, Shigeo Yamauchi, Yasuo Tanaka, Katsuji Koyama

    We have observed a typical Galactic plane field at (l,b) = (28.46d, -0.20d) with Suzaku for 100 ksec to carry out a precise spectral study of the Galactic Ridge X-ray Emission (GRXE). The field is known to be devoid of X-ray point sources brighter than ~2 x 10^{-13} ergs s^{-1} cm^{-2} (2--10 keV), and already deeply observed with Chandra. Thanks to the low

  50. G. Papini, G. Scarpetta, A. Feoli, G. Lambiase

    The Maxwell and Maxwell-de Rham equations can be solved exactly to first order in an external gravitational field. The gravitational background induces phases in the wave functions of spin-1 particles. These phases yield the optics of the particles without requiring any thin lens approximation.

  51. Ioanna Leonidaki, Andreas Zezas, Panayotis Boumis

    We present the initial results from a study of the SNR population in a sample of six nearby galaxies (NGC 2403, NGC 4214, NGC 4449, NGC 5204, NGC 3077, NGC 4395) based on Chandra archival data. We discuss the analysis of the Chandra data and we present candidate SNR sources selected on the basis of their X-ray colours. We also present deep [S II] 6716 & 6731

  52. Didier Mokoko, Martine Pithioux, Patrick Chabrand

    Various mathematical models represent the effects of local mechanical environment on the regulation of skeletal regeneration. Their relevance relies on an accurate description of the evolving mechanical properties of the regenerating tissue. The object of this study was to develop an experimental model which made it possible to characterize the temporal evol

  53. R. Thomas, T. Hilger, B. Kampfer

    The QCD sum rule approach to the in-medium behavior of hadrons is discussed for omega meson, nucleon and D meson. Emphasis is devoted to the impact of four-quark condensates and to order parameters of spontaneous symmetry breaking.

  54. P. Zasche, M. Wolf, P. Svoboda

    The contact eclipsing binary system XX Leonis (P = 0.97 days, sp A8) has been analysed using the PHOEBE programme, based on the Wilson Devinney code. The BVRI light curves were obtained during spring 2006 using the 20-cm telescope and ST-7 CCD detector. The effective temperature of the primary component determined from the photometric analysis is T=(7889+/-6

  55. Takashi Hamazaki

    We present the LWL formula which represents the long wavelengh limit of the solutions of evolution equations of cosmological perturbations in terms of the exactly homogeneous solutions in the most general case where multiple scalar fields and multiple perfect fluids coexist. We find the conserved quantity which has origin in the adiabatic decaying mode, and

  56. Zasche Petr, Zejda Miloslav, Brat Lubos

    The period changes of six eclipsing binaries have been studied with focus on the light-time effect. With the least squares method we also calculated parameters of such an effect and properties of the unresolved body in these systems. With these results we discussed the probability of presence of such bodies in the systems with respect to possible confirmatio

  57. Yunchang Shin, W. Mike Snow, Christopher M. Lavelle, David V. Baxter

    Neutron energy spectrum measurements from a solid methane moderator were performed at the Low Energy Neutron Source (LENS) at Indiana University Cyclotron Facility (IUCF) to verify our neutron scattering model of solid methane. The time-of-flight method was used to measure the energy spectrum of the moderator in the energy range of 0.1$meV\sim$ 1$eV$. Neutro

  58. G. Huber, T. Deuschle, W. Schnitzler, R. Reichle

    We describe the construction and operation of a segmented linear Paul trap, fabricated in printed-circuit-board technology with an electrode segment width of 500 microns. We prove the applicability of this technology to reliable ion trapping and report the observation of Doppler cooled ion crystals of Ca-40 with this kind of traps. Measured trap frequencies

  59. M. Orienti, D. Dallacasa

    Aims: The knowledge of the properties of the youngest radio sources is very important in order to trace the earliest phase of the evolution of the radio emission. RXJ1459+3337, with its high turnover frequency (~25 GHz) provides a unique opportunity to study this class of extreme objects. Methods: High-sensitivity multi-frequency VLA observations have been c

  60. V. N. Biktashev, A. Arutunyan, N. A. Sarvazyan

    We aim to understand the formation of abnormal waves of activity from myocardial regions with diminished cell-to-cell coupling. In route to this goal, we studied the behavior of a heterogeneous myocyte network in which a sharp coupling gradient was placed under conditions of increasing network automaticity. Experiments were conducted in monolayers of neonata

  61. Joakim Arnlind

    We construct C-algebras for a class of surfaces that are inverse images of certain polynomials of arbitrary degree. By using the directed graph associated to a matrix, the representation theory can be understood in terms of ``loop'' and ``string'' representations, which are closely related to the dynamics of an iterated map in the plane. As a

  62. Tai-Hung Wu, Jen-Tsung Hsiang, Da-Shin Lee

    The effects of electromagnetic vacuum fluctuations with the boundary on charged particles is investigated. They may be observed via an electron interference experiment near the conducting plate, where boundary effects of vacuum fluctuations are found significant on coherence reduction of the electrons. The dynamics of the charge under the influence of quanti

  63. S. A. Lamzin, M. M. Romanova, S. A. Kravtsova

    We calculated profiles of CIV 1550, Si IV 1400, NV 1240 and OVI 1035 doublet lines using results of 3D MHD simulations of disc accretion onto young stars with dipole magnetic field. It appeared that our calculations can not reproduce profiles of these lines observed (HST/GHRS-STIS and FUSE) in CTTSs's spectra. We also found that the theory predicts much

  64. Marc Siegmund, Markus Hofmann, Oleg Pankratov

    We use Density Functional Theory to study interacting spinless electrons on a one-dimensional quantum ring in the density range where the system undergoes Wigner crystallization. The Wigner transition leads to a drastic ``collective'' electron localization due to the Wigner crystal pinning, provided a weak impurity potential is applied. To reveal thi

  65. Gábor Kupi

    We give a gravitational upper limit for the mass of static degenerate fermionic dark matter objects. The treatment we use includes fully relativistic equations for describing the static solutions of these objects. We study the influence of the annihilation of the particles on this mass limit. We give the change of its value over the age of the Universe with

  66. Diego Bombardelli, Davide Fioravanti, Marco Rossi

    We survey and discuss the applications of the non-linear integral equation in the framework of the Bethe Ansatz type equations which are conjectured to give the eigenvalues of the dilatation operator in ${\cal {N}}=4$ SYM. Moreover, an original idea (different from that of \cite {FMQR}) to derive a non-linear integral equation is briefly depicted in Section

  67. M. Castellani

    The present status of Galactic Globular Clusters Database is briefly reviewed. The features implemented at the time writing are described, as well as plans for future improvements.

  68. F. Knechtli, N. Irges, M. Luz

    Spontaneous symmetry breaking has been observed in lattice simulations of five-dimensional gauge theories on an orbifold. This effect is reproduced by perturbation theory if it is modified to account for a finite cut-off. We present a comparison of lattice and analytic results for bulk gauge group SU(2).

  69. D. Senff, P. Link, N. Aliouane, D. N. Argyriou

    The field-induced multiferroic transition in TbMnO3 has been studied by neutron scattering. Apart strong hysteresis, the magnetic transition associated with the flop of electronic polarization exhibits a memory effect: after a field sweep, TbMnO3 does not exhibit the same phase as that obtained by zero-field cooling. The strong changes in the magnetic excita

  70. Jonathan Bowden

    We consider circle bundles over compact three-manifolds with symplectic total spaces. We show that the base of such a space must be irreducible or the product of the two-sphere with the circle. We then deduce that such a bundle admits a symplectic form if and only if it admits one that is invariant under the circle action in three special cases: namely if th

  71. T. A. Larsson

    The standard BV complex is never acyclic provided that the equations of motion have solutions and the admissible class of functions is general enough, unless one introduces second-order antifields. This phenomenon is explicitly illustrated for the harmonic oscillator and the free electromagnetic field.

  72. Ingrid Rotter

    In the Feshbach projection operator (FPO) formalism the whole function space is divided into two subspaces. One of them contains the wave functions localized in a certain finite region while the continuum of extended scattering wave functions is involved in the other subspace. The Hamilton operator of the whole system is Hermitian, that of the localized part

  73. Huihui Dai, Yanhong Hao, Zhen Chen

    In this paper, we study the localization phenomena in a slender cylinder composed of an incompressible hyperelastic material subjected to axial tension. We aim to construct the analytical solutions based on a three-dimensional setting and use the analytical results to describe the key features observed in the experiments by others. Using a novel approach of

  74. B. Miszalski, Q. A. Parker, A. Acker, J. L. Birkby

    We present a supplement to the Macquarie/AAO/Strasbourg H$α$ planetary nebulae (PNe) catalogue (MASH), which we denote MASH-II. The supplement consists of over 300 true, likely and possible new Galactic PNe found after re-examination of the entire AAO/UKST H$α$ survey of the southern Galactic Plane in digital form. We have spectroscopically confirmed over 24

  75. Charles Bonatto, Eduardo Bica

    Structural parameters of model star clusters are measured in radial profiles built from number-density, mass-density and surface-brightness distributions, assuming as well different photometric conditions. Star clusters of different ages, structure and mass functions are modelled by assuming that the radial distribution of stars follows a pre-defined analyti

  76. James A. Thom, Jovan Pehcevski, Anne-Marie Vercoustre

    Wikipedia is a useful source of knowledge that has many applications in language processing and knowledge representation. The Wikipedia category graph can be compared with the class hierarchy in an ontology; it has some characteristics in common as well as some differences. In this paper, we present our approach for answering entity ranking queries from the

  77. Gidudu Anthony, Hulley Gregg, Marwala Tshilidzi

    Support Vector Machines (SVMs) are a relatively new supervised classification technique to the land cover mapping community. They have their roots in Statistical Learning Theory and have gained prominence because they are robust, accurate and are effective even when using a small training sample. By their nature SVMs are essentially binary classifiers, howev

  78. M. M. Tung, L. Soler, E. Defez, A. Hervas

    We discuss the direct use of cubic-matrix splines to obtain continuous approximations to the unique solution of matrix models of the type $Y''(x) = f(x,Y(x))$. For numerical illustration, an estimation of the approximation error, an algorithm for its implementation, and an example are given.

  79. Viktor V. Begun

    The aim of this paper is to give a short overview for the set of publications considering recently found effect of non-equivalence of multiplicity fluctuations in relativistic gases with globally conserved charge and energy.

  80. Daniel John Lawson, Henrik Jeldtoft Jensen

    The birth/death process with mutation describes the evolution of a population, and displays rich dynamics including clustering and fluctuations. We discuss an analytical `field-theoretical' approach to the birth/death process, using a simple dimensional analysis argument to describe evolution as a `Super-Brownian Motion' in the infinite population li

  81. S. N. Storchak

    Factorization of the (formal) path integral measure in a Wiener path integrals for Yang--Mills diffusion is studied. Using the nonlinear filtering stochastic differential equation, we perform the transformation of the path integral defined on a total space of the Yang--Mills principal fiber bundle and come to the reduced path integral on a Coulomb gauge surf

  82. Friso Hoefnagels, Keith S Cover, Ester Sanchez, Frank J. Lagerwaard

    Dynamic susceptibility-weighted contrast-enhanced (DSC) MRI or perfusion-MRI plays an important role in the non-invasive assessment of tumor vascularity. However, the large number of images provided by the method makes display and interpretation of the results challenging. Current practice is to display the perfusion information as relative cerebral blood vo

  83. Gregory Schehr, Heiko Rieger

    We study the effect of dissipation on the infinite randomness fixed point and the Griffiths-McCoy singularities of random transverse Ising systems in chains, ladders and in two-dimensions. A strong disorder renormalization group scheme is presented that allows the computation of the finite temperature behavior of the magnetic susceptibility and the spin spec

  84. Joe Zuntz

    We discuss Cosmic Microwave Background constraints on the causal set theory of quantum gravity, which has made testable predictions about the nature of dark energy. We flesh out previously discussed heuristic constraints by showing how the power spectrum of causal set dark energy fluctuations can be found from the overlap volumes of past light cones of point

  85. A. Masiero, S. K. Vempati, O. Vives

    In spite of the enormous success of the Standard Model (SM), we have strong reasons to expect the presence of new physics beyond the SM at higher energies. The idea of the Grand Unification of all the known interactions in nature is perhaps the main reason behind these expectations. Low-energy Supersymmetry is closely linked with grand unification as a solut

  86. S. D. Brown, P. Strange, L. Bouchenoire, B. Zarychta

    We report measured dipolar asymmetry ratios at the LIII edges of the heavy rare earth metals. The results are compared with a first principles calculation and excellent agreement is found. A simple model of the scattering is developed, enabling us to re-interpret the resonant x-ray scattering in these materials and to identify the peaks in the asymmetry rati

  87. G. Cristofano, V. Marotta, P. Minnhagen, A. Naddeo

    The issue of the number, nature and sequence of phase transitions in the fully frustrated XY (FFXY) model is a highly non trivial one due to the complex interplay between its continuous and discrete degrees of freedom. In this contribution we attack such a problem by means of a twisted conformal field theory (CFT) approach and show how it gives rise to the U

  88. J. Izquierdo, M. M. Tung, R. Perez, F. J. Martinez

    State estimation is necessary in diagnosing anomalies in Water Demand Systems (WDS). In this paper we present a neural network performing such a task. State estimation is performed by using optimization, which tries to reconcile all the available information. Quantification of the uncertainty of the input data (telemetry measures and demand predictions) can

  89. P. A. Bhobe, K. R. Priolkar, A. K. Nigam

    We have studied the effect of magnetic field on a non-stoichiometric Heusler alloy Ni$_{50}$Mn$_{35}$In$_{15}$ that undergoes a martensitic as well as a magnetic transition near room temperature. Temperature dependent magnetization measurements demonstrate the influence of magnetic field on the structural phase transition temperature. From the study of magne

  90. I. Agnolin, N. P. Kruyt

    We determine the elastic moduli of two-dimensional assemblies of disks by computer simulations. The disks interact through elastic contact forces, that oppose the relative displacement at the contact points by means of a normal and a tangential stiffness, both taken constant. Our simulations confirm that the uniform strain assumption results in inaccurate pr

  91. Anna Carbone

    We propose an algorithm to estimate the Hurst exponent of high-dimensional fractals, based on a generalized high-dimensional variance around a moving average low-pass filter. As working examples, we consider rough surfaces generated by the Random Midpoint Displacement and by the Cholesky-Levinson Factorization algorithms. The surrogate surfaces have Hurst ex

  92. Xuguang Huang, Xuewen Hao, Pengfei Zhuang

    We investigate the phase diagram in the plane of temperature and chemical potential mismatch for an asymmetric fermion superfluid with double- and single-species pairings. There is no mixing of these two types of pairings at fixed chemical potential, but the introduction of the single species pairing cures the magnetic instability at low temperature.

  93. Alain Gelle, Marie-Bernadette Lepetit

    An efficient real space method is derived for the evaluation of the Madelung's potential of ionic crystals. The proposed method is an extension of the Evjen's method. It takes advantage of a general analysis for the potential convergence in real space. Indeed, we show that the series convergence is exponential as a function of the number of annulled

  94. A. R. Yeates, D. H. Mackay, A. A. van Ballegooijen

    The hemispheric pattern of solar filaments is considered using newly-developed simulations of the real photospheric and 3D coronal magnetic fields over a 6-month period, on a global scale. The magnetic field direction in the simulation is compared directly with the chirality of observed filaments, at their observed locations. In our model the coronal field e

  95. Warren R. Brown, Timothy C. Beers, Ronald Wilhelm, Carlos Allende Prieto

    We present a complete spectroscopic survey of 2414 2MASS-selected blue horizontal branch (BHB) candidates selected over 4300 deg^2 of the sky. We identify 655 BHB stars in this non-kinematically selected sample. We calculate the luminosity function of field BHB stars and find evidence for very few hot BHB stars in the field. The BHB stars located at a distan

  96. Omer Offen, Eitan Sayag

    We show the uniqueness and disjointness of Klyachko models for GL(n,F) over a non-archimedean local field F. This completes, in particular, the study of Klyachko models on the unitary dual. Our local results imply a global rigidity property for the discrete automorphic spectrum.

  97. B. V. R. Tata, P. S. Mohanty, M. C. Valsakumar

    We report observations of stable bound pairs in very dilute deionized aqueous suspensions of highly charged polystyrene colloidal particles, with monovalent counterions, using a confocal laser scanning microscope. Through an analysis of several thousands of time series of confocal images recorded deep inside the bulk suspension, we find that the measured pai

  98. Gerhard Baur

    A brief introduction to the physics of ultraperipheral collisions at collider energies is given. Photon-hadron (proton/ nucleus) and photon-photon interactions can be studied in a hitherto unexplored energy regime.

  99. M. Puech, F. Hammer, L. Chemin, H. Flores

    We compare both the Milky Way and M31 to local external disk galaxies within the same mass range, using their relative locations in the planes formed by Vflat vs. MK (the Tully-Fisher relation), j_disk (specific angular momentum) and the average Fe abundance of stars in the galaxy outskirts. We find, for all relationships, that the MW is systematically offse

  100. Josep Lluís Solé, Frederic Utzet

    An explicit procedure to construct a family of martingales generated by a process with independent increments is presented. The main tools are the polynomials that give the relationship between the moments and cumulants, and a set of martingales related to the jumps of the process called Teugels martingales