September 2002 arXiv papers — page 5
Showing 401–500 of 3,263 papers
Alexander Dynin
We consider functional Schrödinger equations associated with a wide class of Hamiltonians in all Fock representations of the bosonic canonical commutation relations, in particular the Cook-Fock, Friedrichs-Fock, and Bargmann-Fock models. An infinite-dimensional symbolic calculus allows us to prove the convergence of the corresponding Hamiltonian Feynman inte
Karen E. Smith
This is an expanded version of the author's lecture at the Conference in Commutative Algebra and Algebraic Geometry in Messina Italy in June 1999. The purpose of the talk was to give a brief introduction to the subject of tight closure, aimed at commutative algebraists who have not before studied this topic. The first part focused mainly on the definitio
Manfred Schocker
The linear span P_n of the sums of all permutations in the symmetric group S_n with a given set of peaks is a sub-algebra of the symmetric group algebra, due to Nyman. This peak algebra is a left ideal of the descent algebra D_n; and the direct sum P of all P_n is a Hopf sub-algebra of the direct sum D of all D_n, dual to the Stembridge algebra of peak funct
Ngo Viet Trung
We present a constructive description of minimal reductions with a given reduction number. This description has interesting consequences on the minimal reduction number, the big reduction number, and the core of an ideal. In particular, it helps solve a conjecture of Vasconcelos on the relationship between reduction numbers and initial ideals.
Adela Vraciu
We study the relationship between the tight closure of an ideal and the sum of all ideals in its linkage class.
Holger Brenner
We give a complete and consistent formal interpretation of the modal logic of Aristotle as developped in his analytics.
Holger Brenner
In this paper we consider the open complement U of a hypersurface Y=V(a) in an affine scheme X. We study the relations between the affineness of U, the intersection of Y with closed subschemes, the property that every closed surface in U is affine, the property that every analytic closed surface is Stein and the superheight of the defining ideal a.
Holger Brenner
In this paper we study the ring of global sections of an open subset U=D(I) in Spec A, where A is a two-dimensional noetherian ring. The main concern is to give a geometric criterion when these rings are finitely generated, in order to correct an invalid statement of Schenzel.
Olivier Mejane
We consider the model of directed polymers in a random environment introduced by Petermann : the random walk is $\mathbb{R}^d$-valued and has independent gaussian $N(0,I_d)$-increments, and the random media is a stationary centred Gaussian process $(g(k,x), k \geq 1, x \in \mathbb{R}^d)$ with covariance matrix $cov(g(i,x),g(j,y))=δ_{ij} Γ(x-y) ,$ where $Γ$ i
Sara Faridi
For a graded domain $R=k[X_0,...,X_m]/J$ over an arbitrary domain $k$, it is shown that the ideal generated by elements of degree $\geq mA$, where $A$ is the least common multiple of the weights of the $X_i$, is a normal ideal.
Juergen Bokowski, Simon King, Susanne Mock, Ileana Streinu
We present a new direct proof of a topological representation theorem for oriented matroids in the general rank case. Our proof is based on an earlier rank 3 version. It uses hyperline sequences and the generalized Sch{ö}nflies theorem. As an application, we show that one can read off oriented matroids from arrangements of embedded spheres of codimension one
Adrian Iovita, Annette Werner
We prove that for abelian varieties with semistable ordinary reduction the p-adic Mazur-Tate height pairing is induced by the unit root splitting of the Hodge filtration on the first deRham cohomology.
Mordechai Katzman
The paper shows that if the set of associated primes of Frobenius powers of ideals or a closely related set of primes is finite then if tight closure does not commute with localisation one can find a counter-example where $R$ is complete local and we are localizing at a prime ideal $P \subset R$ with $\dim (R/P)=1$. If one assumes further that for any local
Dinakar Ramakrishnan
In this Note we show that given any cusp form πon GL(3) over the rationals, there exist an infinite number of primes p which are Ramanujan for π, i.e., that the local components π_p are tempered for an infinite number of p. It turns out that the key structural device which is needed is the degree 8 adjoint L-function of π.
Jerzy Stryla
I begin from a particular field of generalised Puiseux series and investigate a class of nonlinear differential equations in the field. It is appeared that the main part of differential equation determines solvability and positions of resonance i.e. the appearance of a free constant in solutions. Secondly, for any singular differential equation in a differen
Nemanja Kaloper, Matthew Kleban, Albion Lawrence, Stephen Shenker
Free scalar fields in de Sitter space have a one-parameter family of states invariant under the de Sitter group, including the standard thermal vacuum. We show that, except for the thermal vacuum, these states are unphysical when gravitational interactions are included. We apply these observations to the quantum state of the inflaton, and find that, at best,
On Algebraic Singularities, Finite Graphs and D-Brane Gauge Theories: A String Theoretic Perspective
hep-thYang-Hui He
In this writing we shall address certain beautiful inter-relations between the construction of 4-dimensional supersymmetric gauge theories and resolution of algebraic singularities, from the perspective of String Theory. We review in some detail the requisite background in both the mathematics, such as orbifolds, symplectic quotients and quiver representatio
Felix Lev
As shown in our previous papers (hep-th/0209001 and reference therein), quantum theory based on a Galois field (GFQT) possesses a new symmetry between particles and antiparticles, which has no analog in the standard approach. In the present paper it is shown that this symmetry (called the AB one) is also compatible with supersymmetry. We believe this is a st
Bo Feng, Sebastian Franco, Amihay Hanany, Yang-Hui He
We develop an unhiggsing procedure for finding the D-brane probe world volume gauge theory for blowups of geometries whose gauge theory data are known. As specific applications we unhiggs the well-studied theories for the cone over the third del Pezzo surface. We arrive at what we call pseudo del Pezzos and these will constitute a first step toward the under
Nima Arkani-Hamed, Savas Dimopoulos, Gia Dvali, Gregory Gabadadze
We propose a phenomenological approach to the cosmological constant problem based on generally covariant non-local and acausal modifications of four-dimensional gravity at enormous distances. The effective Newton constant becomes very small at large length scales, so that sources with immense wavelengths and periods -- such as the vacuum energy-- produce min
Yi Liao, Klaus Sibold
We study the spectral representation and dispersion relations that follow from some basic assumptions and the reduced spacetime symmetries on noncommutative (NC) space. Kinematic variables involving the NC parameter appear naturally as parametric variables in this analysis. When subtractions are necessary to remove ultraviolet divergences, they are always ma
Shijong Ryang
We construct the Penrose limit backgrounds in closed forms along the generic null geodesics for the near-horizon geometries of D1, D3, D5, NS1 and NS5 branes. The Penrose limit metrics of D1, D5 and NS1 have non-trivial dependence of the light-cone time coordinate, while those of D3 and NS5 have no its dependence. We study the Penrose limits on the marginal
A. J. M. Medved
There has been substantial interest in obtaining a quantum-gravitational description of de Sitter space. However, any such attempts have encountered formidable obstacles, and new philosophical directions may be in order. One possibility, although somewhat speculative, would be to view the physical universe as a timelike hypersurface evolving in a higher-dime
Ernest Ma
The recently proposed supersymmetric $A_4$ model of the neutrino mass matrix is modified to merge with a previously proposed axionic solution of the strong CP problem. The resulting model has only one input scale, i.e. that of $A_4$ symmetry breaking, which determines both the seesaw neutrino mass scale and the axion decay constant. It also solves the $μ$ pr
F. Hautmann
We study jet final states in diffractive deep-inelastic scattering. We present the QCD factorization formula in terms of diffractive parton distributions and discuss its implementation in NLO Monte Carlo generators. We compute NLO predictions for the diffractive jet cross section. We use this calculational framework to discuss theoretical models of the long-
Paul Hoyer
The quark <\barψψ> and gluon <F_{μν}F^{μν}> vacuum expectation values are non-vanishing at low orders in α_s when the perturbative ground state includes quark and gluon pairs. This offers possibilities of studying the effects of a non-trivial vacuum using formally exact perturbative methods. The QCD Feynman rules are modified only for the free, on-shell quar
Paul Hoyer
Parton distributions given by deep inelastic lepton scattering (DIS) are not equal to the probabilities of finding those partons in the parent wave function. Soft rescattering of the struck parton within the coherence length of the hard process influences the DIS cross section and gives dynamical phases to the scattering amplitudes. This gives rise to diffra
K. J. Eskola, H. Honkanen, V. J. Kolhinen, P. V. Ruuskanen
We explain how the constraints from present experimental data can be used to obtain the nPDF in the framework of LO DGLAP evolution. We will also compare the only two available sets of this type and comment on the important information that neutrino factories could provide.
B. L. Ioffe
The recent results in QCD at low energies are reported. The theoretical analysis of hadronic tau-decay is performed in complex q^2-plane. The terms of perturbation theory (PT) up to alpha^3_s are accounted, the terms of operator product expansion (OPE) -- up do dimension 8. The momenta of charmed quark vector current polarization operator are analyzed in 3 l
A. Banfi
We describe a numerical procedure to resum multiple emission effects in event shape variables and jet rates.
Tai-Fu Feng, Xue-Qian Li, Yan-An Luo
Inspired by the recent HEIDELBERG-MOSCOW double beta decay experiment, we discuss the neutrinoless double beta decay in the supersymmetric seesaw model. Our numerical analysis indicates that we can naturally explain the data of the observed neutrinoless double beta decay, as well as that of the solar and atmospheric neutrino experiments with at least one Maj
Stephen P. Martin, James D. Wells
The recent developments in theory and experiment related to the anomalous magnetic moment of the muon are applied to supersymmetry. We follow a very cautious course, demanding that the supersymmetric contributions fit within five standard deviations of the difference between experiment and the standard model prediction. Arbitrarily small supersymmetric contr
W. Bardeen, E. Eichten, H. Thacker
We present results of a high-statistics study of scalar and pseudoscalar meson propagators in quenched QCD at two values of lattice spacing, beta = 5.7 and 5.9, with clover-improved Wilson fermions. The study of the chiral limit is facilitated by the pole-shifting ansatz of the modified quenched approximation. Pseudoscalar masses and decay constants are dete
MILC Collaboration, C. Bernard, T. Burch, S. Datta
During the past year the MILC Collaboration has continued its study of heavy-light meson decay constants with three dynamical quarks. Calculations have been extended to a second lattice spacing of about 0.09 fm. At this lattice spacing, there are results in the quenched approximation and for three sets of dynamical quark mass: m_l=m_s; m_l=0.4 m_s and m_l=0.
Rainer Sommer
We discuss the necessity of non-perturbative renormalization in QCD and HQET and explain the general strategy for solving this problem. A few selected topics are discussed in some detail, namely the importance of off-shell improvement in the MOM-scheme on the lattice, recent progress in the implementation of finite volume schemes and then particular emphasis
Mushtaq Loan, Michael Brunner, Chris Hamer
A numerical study of low-lying glueball masses of compact U(1) lattice gauge theory in (2+1) dimensions is performed using Standard Path integral Monte Carlo techniques. The masses are extracted, at fixed (low) temperature, from simulations on anisotropic lattices, with temporal lattice spacing much smaller than the spatial ones. Convincing evidence of the s
M. Göckeler, R. Horsley, D. Pleiter, P. E. L. Rakow
The progress on the lattice computation of low moments of both the unpolarised and polarised nucleon structure functions is reviewed with particular emphasis on continuum and chiral extrapolations and comparison between quenched and unquenched fermions.
q Collaboration, F. Farchioni, C. Gebert, I. Montvay
The computational cost of numerical simulations of QCD with light dynamical Wilson-quarks is estimated. The qualitative behaviour of the pion mass and coupling at small quark masses is discussed.
V. Daniel Elvira
DO has implemented and calibrated a KT jet algorithm for the first time in a ppbar collider. We present two results based on 1992-1996 data which were recently published: the subjet multiplicity in quark and gluon jets and the central inclusive jet cross section. The measured ratio between subjet multiplicities in gluon and quark jets is consistent with theo
HERMES Collaboration, A. Airapetian
Exclusive coherent and incoherent electroproduction of the $ρ^0$ meson from $^1$H and $^{14}$N targets has been studied at the HERMES experiment as a function of coherence length ($l_c$), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared four-momentum of the virtual photon ($-Q^2$). The ratio of $^{14}$N to $^1$H cross
D. Muller, H. V. Fagundes, R. Opher
We generalize a previously obtained result, for the case of a few other static hyperbolic universes with manifolds of nontrivial topology as spatial sections.
Matthew D. Duez, Pedro Marronetti, Stuart L. Shapiro, Thomas W. Baumgarte
We solve Einstein's field equations coupled to relativistic hydrodynamics in full 3+1 general relativity to evolve astrophysical systems characterized by strong gravitational fields. We model rotating, collapsing and binary stars by idealized polytropic equations of state, with neutron stars as the main application. Our scheme is based on the BSSN formul
Curt Cutler, William A. Hiscock, Shane L. Larson
We extend and improve earlier estimates of the ability of the proposed LISA (Laser Interferometer Space Antenna) gravitational wave detector to place upper bounds on the graviton mass, m_g, by comparing the arrival times of gravitational and electromagnetic signals from binary star systems. We show that the best possible limit on m_g obtainable this way is ~
Precession of a particle with anomalous magnetic moment in electromagnetic and gravitational pp-wave fields
gr-qcAlexander Balakin, Veronika Kurbanova, Winfried Zimdahl
We present an exact solution of the Bargmann-Michel-Telegdi (BMT) equations for the dynamics of a spin particle in external electromagnetic and gravitational pp-wave fields. We demonstrate that an anomalous magnetic moment gives rise to an additional spin rotation which is modulated both by the electromagnetic and by the gravitational wave periodicities.
Michael J. S. L. Ashley
The abstract boundary has, in recent years, proved a general and flexible way to define the singularities of space-time. In this approach an essential singularity is a non-regular boundary point of an embedding which is accessible by a chosen family of curves within finite parameter distance. Ashley and Scott proved the first theorem relating essential singu
Adriana Iamnitchi, Matei Ripeanu, Ian Foster
Data-sharing scientific collaborations have particular characteristics, potentially different from the current peer-to-peer environments. In this paper we advocate the benefits of exploiting emergent patterns in self-configuring networks specialized for scientific data-sharing collaborations. We speculate that a peer-to-peer scientific collaboration network
Stefan Boettcher, Allon G. Percus
A recently introduced general-purpose heuristic for finding high-quality solutions for many hard optimization problems is reviewed. The method is inspired by recent progress in understanding far-from-equilibrium phenomena in terms of {\em self-organized criticality,} a concept introduced to describe emergent complexity in physical systems. This method, calle
Julián Candia, Ezequiel V. Albano
The irreversible growth of a magnetic film with spins having two possible orientations is studied in three-dimensional confined geometries of size $L\times L\times M$, where $M\gg L$ is the growing direction. A competing situation with two opposite short range surface magnetic fields $H$ of the same magnitude is analyzed. Due to the antisymmetric condition c
Thermodynamic QED Coherence in Condensed Matter: Microscopic Basis of Thermal Superradiance
cond-mat.stat-mechS. Sivasubramanian, A. Widom, Y. N. Srivastava
Electromagnetic superradiant field coherence exists in a condensed matter system if the electromagnetic field oscillators undergo a mean displacement. Transitions into thermal states with ordered superradiant phases have been shown to theoretically exist in Dicke-Preparata models. The theoretical validity of these models for condensed matter has been called
A. Franceschetti, S. T. Pantelides
Excited-state relaxations in molecules are responsible for a red shift of the absorption peak with respect to the emission peak (Franck-Condon shift). The magnitude of this shift in semiconductor quantum dots is still unknown. Here we report first-principle calculations of excited-state relaxations in small (diameter < 2.2 nm) Si nanocrystals, showing that t
Twist of cholesteric liquid crystal cell with substrates of different anchoring strengths
cond-mat.mtrl-sciA. D. Kiselev
We consider director configurations of cholesteric liquid crystal (CLC) cells with two plane confining substrates. Exact solutions of the Euler-Lagrange equations for out-of-plane orientations of the easy axes that correspond to inhomogeneous conical structures of CLC director are derived. We study dependence of the CLC twist wavenumber on the free twisting
J. C. Xavier, E. Novais, E. Miranda
We study the one-dimensional Kondo lattice model through the density matrix renormalization group (DMRG). Our results for the spin correlation function indicate the presence of a small Fermi surface in large portions of the phase diagram, in contrast to some previous studies that used the same technique. We argue that the discrepancy is due to the open bound
Dimitris Achlioptas, Cristopher Moore
Form a random k-SAT formula on n variables by selecting uniformly and independently m=rn clauses out of all 2^k (n choose k) possible k-clauses. The Satisfiability Threshold Conjecture asserts that for each k there exists a constant r_k such that, as n tends to infinity, the probability that the formula is satisfiable tends to 1 if r < r_k and to 0 if r > r_
Controlling two-species Mott-insulator phses in an optical lattice to form an array of dipolar molecules
cond-matM. G. Moore, H. R. Sadeghpour
We consider the transfer of a two-species Bose-Einstein condensate into an optical lattice with a density such that that a Mott-insulator state with one atom per species per lattice site is obtained in the deep lattice regime. Depending on collision parameters the result could be either a `mixed' or a `separated' Mott-insulator phase. Such a `mixed&#
Roberto Percacci, Alessandro Vespignani
Measurements and data analysis have proved very effective in the study of the Internet's physical fabric and have shown heterogeneities and statistical fluctuations extending over several orders of magnitude. Here we analyze performance measurements obtained by the PingER monitoring infrastructure. We focus on the relationship between the Round-Trip-Time
Free Energy Minimizers for a Two--Species Model with Segregation and Liquid-Vapor Transition
cond-mat.stat-mechE. A. Carlen, M. C. Carvalho, R. Esposito, J. L. Lebowitz
We study the coexistence of phases in a two--species model whose free energy is given by the scaling limit of a system with long range interactions (Kac potentials) which are attractive between particles of the same species and repulsive between different species.
Effect of LaAlO$_3$ Surface Topography on RF Current Distribution in Superconducting Microwave Devices
cond-mat.supr-conA. P. Zhuravel, A. V. Ustinov, H. Harshavardhan, Steven M. Anlage
A laser scanning microscope with a thermal spot size of about 4 $μ$m is used to measure a quantity proportional to the rf current density in an operating superconducting co-planar waveguide microwave resonator. The twinning of the LaAlO$_3$ substrate produces a meandering of the current at the edges due to irregularities in the wet etching of the YBa$_2$Cu$_
Viral evolution under the pressure of an adaptive immune system - optimal mutation rates for viral escape
cond-mat.stat-mechChristel Kamp, Claus O. Wilke, Christoph Adami, Stefan Bornholdt
Based on a recent model of evolving viruses competing with an adapting immune system [1], we study the conditions under which a viral quasispecies can maximize its growth rate. The range of mutation rates that allows viruses to thrive is limited from above due to genomic information deterioration, and from below by insufficient sequence diversity, which lead
H. Bernas, D. Halley, K. -H. Heinig, J. -Ph. Attane
Combining He ion irradiation and thermal mobility below 600K, we both trigger and control the transformation from chemical disorder to order in thin films of an intermetallic ferromagnet (FePd). Kinetic Monte Carlo simulations show how the initial directional short range order determines order propagation. Magnetic ordering perpendicular to the film plane wa
Magnetization orientation dependence of the quasiparticle spectrum and hysteresis in ferromagnetic metal nanoparticles
cond-matA. Cehovin, C. M. Canali, A. H. MacDonald
We use a microscopic Slater-Koster tight-binding model with short-range exchange and atomic spin-orbit interactions that realistically captures generic features of ferromagnetic metal nanoparticles to address the mesoscopic physics of magnetocrystalline anisotropy and hysteresis in nanoparticle quasiparticle excitation spectra. Our analysis is based on quali
Jean-Louis Barrat, François Chiaruttini
Using equilibrium and nonequilibrium molecular dynamics simulations, we determine the Kapitza resistance (or thermal contact resistance) at a model liquid solid interface. The Kapitza resistance (or the associated Kapitza length) can reach appreciable values when the liquid does not wet the solid. The analogy with the hydrodynamic slip length is discussed.
Arnd Bäcker, Achim Manze, Bodo Huckestein, Roland Ketzmerick
We study the isolated resonances occurring in conductance fluctuations of ballistic electron systems with a classically mixed phase space. In particular, we calculate the conductance and Wigner-Smith time as well as scattering states and eigenstates of the open and closed cosine billiard, respectively. We demonstrate that the observed isolated resonances and
Cation intermixing and ordering phenomenon in MO layer of MSr2YCu2Oz (M1212) compounds with M = Fe, Co, Al, and Ga: A neutron powder diffraction study
cond-mat.supr-conV. P. S. Awana, E. Takayama-Muromachi, S. K. Malik, W. B. Yelon
Various MSr2YCu2Oz (M1212 with M = Fe, Co, Al and Ga) compounds have been synthesized through a solid state reaction route. All these compounds are derived from the basic CuBa2YCu2O7 structure. Rietveld structural refinement of the room-temperature neutron diffraction data for Fe-1212 reveals that nearly half of Fe remains at the M site, while the other half
Efficient Selfconsistent Calculations of Multiband Superconductivity in UPd$_2$Al$_3$
cond-mat.supr-conP. M. Oppeneer, G. Varelogiannis
An efficient physically motivated computational approach to multiband superconductivity is introduced and applied to the study of the gap symmetry in a heavy-fermion, UPd$_2$Al$_3$. Using realistic pairing potentials and accurate energy bands that are computed within density functional theory, self-consistent calculations demonstrate that the only accessible
Lattice dynamics and correlated atomic motion from the atomic pair distribution function
cond-mat.mtrl-sciI. -K. Jeong, R. H. Heffner, M. J. Graf, S. J. L. Billinge
The mean-square relative displacements (MSRD) of atomic pair motions in crystals are studied as a function of pair distance and temperature using the atomic pair distribution function (PDF). The effects of the lattice vibrations on the PDF peak widths are modelled using both a multi-parameter Born von-Karman (BvK) force model and a single-parameter Debye mod
Ravi Subrahmanyan, R. D. Ekers
We examine the prospects for observations of CMB anisotropy with the SKA; we discuss the advantages of interferometric SKA imaging, observing strategies, calibration issues and the achievable sensitivity. Although the SKA will probably operate at cm wavelengths, where discrete source confusion dominates the CMB anisotropy, its extreme sensitivity to point so
R. D. Mathieu, M. van den Berg, G. Torres, D. Latham
We report the discovery of two spectroscopic binaries in the field of the old open cluster M67 -- S1063 and S1113 -- whose positions in the color-magnitude diagram place them approximately 1 mag below the subgiant branch. A ROSAT study of M67 independently discovered these stars to be X-ray sources. Both have proper-motion membership probabilities greater th
CMB Anisotropy Constraints on Flat-Lambda and Open CDM Cosmogonies from DMR, UCSB South Pole, Python, ARGO, MAX, White Dish, OVRO, and SuZIE Data
astro-phPia Mukherjee, Ken Ganga, Bharat Ratra, Graca Rocha
We use joint likelihood analyses of combinations of fifteen cosmic microwave background (CMB) anisotropy data sets from the DMR, UCSB South Pole 1994, Python I--III, ARGO, MAX 4 and 5, White Dish, OVRO, and SuZIE experiments to constrain cosmogonies. We consider open and spatially-flat-Lambda cold dark matter cosmogonies, with nonrelativistic-mass density pa
Andrew J. Fox, Blair D. Savage, Kenneth R. Sembach, Dirk Fabian
We present Hubble Space Telescope Imaging Spectrograph (HST/STIS) and Far Ultraviolet Spectroscopic Explorer (FUSE) observations of high ion interstellar absorption along the sight line to HD 116852. At a distance of 4.8 kpc, HD 116852 is an O9 III star lying in the low Galactic halo, -1.3 kpc from the plane of the Galaxy in the direction l = 304.9, b = -16.
A. J. Barth, L. C. Ho, W. L. W. Sargent
We have measured the central stellar velocity dispersions of 33 nearby spiral and elliptical galaxies, using a straightforward template-fitting algorithm operating in the pixel domain. The spectra, obtained with the Double Spectrograph at Palomar Observatory, cover both the Ca triplet and the Mg b region, and we present a comparison of the velocity dispersio
A. J. Barth, L. C. Ho, W. L. W. Sargent
We have measured the central stellar velocity dispersion in the host galaxies of 11 BL Lac objects with redshifts z <= 0.125. The range of velocity dispersions, 170-370 km/s, is similar to that of nearby radio galaxies. Using the correlation between stellar velocity dispersion and black hole mass defined for nearby galaxies, we derive estimates of the black
Andrew Gould, Christopher W. Morgan
In searches for planetary transits in the field, well over half of the survey stars are typically giants or other stars that are too large to permit straightforward detection of planets. For all-sky searches of bright V<~11 stars, the fraction is ~90%. We show that the great majority of these contaminants can be removed from the sample by analyzing their red
Application of Monte Carlo Algorithms to the Bayesian Analysis of the Cosmic Microwave Background
astro-phJ. Jewell, S. Levin, C. H. Anderson
Power spectrum estimation and evaluation of associated errors in the presence of incomplete sky coverage; non-homogeneous, correlated instrumental noise; and foreground emission is a problem of central importance for the extraction of cosmological information from the cosmic microwave background. We develop a Monte Carlo approach for the maximum likelihood e
R. Glenn Morris, A. C. Fabian
In an attempt to reconcile recent spectral data with predictions of the standard cooling flow model, it has been suggested that the metals in the intracluster medium (ICM) might be distributed inhomogeneously on small scales. We investigate the possible consequences of such a situation within the framework of the cooling flow scenario. Using the standard iso
Massimo Ricotti
I analyze the properties of the first galaxies in cosmological simulations with radiative feedback. Preliminary results indicate similarities with the observed properties of the bulk of dwarf spheroidal galaxies (dSphs) in the Local Group and Andromeda. I briefly discuss observational tests that could help in understanding the impact of a population of small
Richard S. Pokorny, Hugh R. A. Jones, Nigel C. Hambly
We present a catalogue of 6206 stars which have proper motions exceeding 0.18 arcsec/yr with an R-band faint magnitude limit of 19.5 mag. This catalogue has been produced using SuperCOSMOS digitized R-Band ESO and UK Schmidt Plates in 131 Schmidt fields covering more than 3,000 square degrees (> 7.5% of the whole sky) at the South Galactic Cap. The survey is
A. Karle
IceCube is a large neutrino telescope of the next generation to be constructed in the Antarctic Ice Sheet near the South Pole. We present the conceptual design and the sensitivity of the IceCube detector to predicted fluxes of neutrinos, both atmospheric and extra-terrestrial. A complete simulation of the detector design has been used to study the detector&#
M. Odenkirchen, E. K. Grebel, W. Dehnen, H. -W. Rix
Sloan Digital Sky Survey data for the field of the globular cluster Pal 5 reveal the existence of a long massive stream of tidal debris spanning an arc of 10 degrees on the sky. Pal 5 thus provides an outstanding example for tidal disruption of globular clusters in the Milky Way. Radial velocities from VLT spectra show that Pal 5 has an extremely low velocit
A. V. Dorodnitsyn
We propose a general physical mechanism which could contribute to the formation of fast line-driven outflows at the vicinity of strong gravitational field sources. We argue that the gradient of the gravitational potential plays the same role as the velocity gradient plays in Sobolev approximation. Both Doppler effect and gravitational redshifting are taken i
Second Parameter Globulars and Dwarf Spheroidals around the Local Group Massive Galaxies: What Can They Evidence?
astro-phValery V. Kravtsov
We suggest that the majority of the "young", so--called "second parameter" globular clusters (SPGCs) have originated in the outer Galactic halo due to a process other than a tidal disruption of the dwarf spheroidal (dSph) galaxies. Basic observational evidence regarding both the dSphs and the SPGCs, coupled with the latest data about a rather
A. Vikhlinin, M. Markevitch
This conference presentation discusses a Chandra observation of the cold front in Abell 3667. We first review our earlier results which include a measurement of the front velocity, M~1, using the ratio of exterior and interior gas pressures; observations of the hydrodynamic effects expected for a transonic front motion (weak bow shock and gas compression nea
G. Aldering, SNAP collaboration
The SuperNova / Acceleration Probe (SNAP) is a space-based experiment to measure the expansion history of the Universe and study both its dark energy and the dark matter. The experiment is motivated by the startling discovery that the expansion of the Universe is accelerating. A 0.7 square-degree imager comprised of 36 large format fully-depleted n-type CCD&
Measurement of B mixing Frequency and CP Violation parameter sin2beta at B factory experiments
hep-exYibin Pan
Recent results on B mixing and CP violation from the B-factory experiments, BABAR and Belle are summarized.
Gia Dvali, Alexander Vilenkin
We point out some intriguing analogies between field theoretic solitons (topological defects) and D-branes. Annihilating soliton-antisoliton pairs can produce stable solitons of lower dimensionality. Solitons that localize massless gauge fields in their world volume automatically imply the existence of open flux tubes ending on them and closed flux tubes pro
Massive Star Formation Rates and Radial Distributions from Halpha Imaging of 84 Virgo Cluster and Isolated Spiral Galaxies
astro-phRebecca A. Koopmann, Jeffrey D. P. Kenney
The massive star formation properties of 55 Virgo Cluster and 29 isolated S0-Scd bright (M(B) < -18) spiral galaxies are compared via analyses of R and Halpha surface photometry and integrated fluxes as functions of Hubble type and central R light concentration (bulge-to-disk ratio). In the median, the total normalized massive star formation rates (NMSFRs) i
Athanasios Dedes, Apostolos Pilaftsis
We derive the general resummed effective Lagrangian for Higgs-mediated flavour-changing neutral-current (FCNC) interactions in the Minimal Supersymmetric Standard Model (MSSM), without resorting to particular assumptions that rely on the squark-mass or the quark-Yukawa structure of the theory. In our derivation we also include the possibility of explicit CP
Mariana Frank, Shuquan Nie
We analyze $B^0_d-{\bar B}^0_d$ mixing in a fully left-right supersymmetric model. We give explicit expressions for all the chargino, gluino, gluino-neutralino and neutralino amplitudes involved in the process. We calculate the mass difference $Δm_d$ and CP asymmetry $a_{J/ψK_s}$ in both the constrained case (where the only flavor violation comes from the Ca
Matthias Klein
We analyze the transmission of supersymmetry breaking in brane-world models of pseudo-supersymmetry. In these models two branes preserve different halves of the bulk supersymmetry. Thus supersymmetry is broken although each sector of the model is supersymmetric when considered separately. The world-volume theory on one brane feels the breakdown of supersymme
Christiaan Hofman, Jae-Suk Park
We study bulk-boundary correlators in topological open membranes. The basic example is the open membrane with a WZ coupling to a 3-form. We view the bulk interaction as a deformation of the boundary string theory. This boundary string has the structure of a homotopy Lie algebra, which can be viewed as a closed string field theory. We calculate the leading or
K. Splittorff, J. J. M. Verbaarschot
In a recent breakthrough Kanzieper showed that it is possible to obtain exact nonperturbative Random Matrix results from the replica limit of the corresponding Painlevé equation. In this article we analyze the replica limit of the Toda lattice equation and obtain exact expressions for the resolvent of the chiral Unitary Ensemble both in the quenched limit an
Osvaldo M. Moreschi
There are several definitions of the notion of angular momentum in general relativity. However non of them can be said to capture the physical notion of intrinsic angular momentum of the sources in the presence of gravitational radiation. We present a definition which is appropriate for the description of intrinsic angular momentum in radiative spacetimes. T
Knut Smoczyk, Mu-Tao Wang
This article studies the mean curvature flow of Lagrangian submanifolds. In particular, we prove the following global existence and convergence theorem: if the potential function of a Lagrangian graph in T^{2n} is convex, then the flow exists for all time and converges smoothly to a flat Lagrangian submanifold.
S. Drozdz, F. Grummer, F. Ruf, J. Speth
A hypothesis that the financial log-periodicity, cascading self-similarity through various time scales, carries signatures of a law is pursued. It is shown that the most significant historical financial events can be classified amazingly well using a single and unique value of the preferred scaling factor lambda=2, which indicates that its real value should
K. Agashe, A. Delgado
It has been conjectured that the (weakly coupled) Randall-Sundrum (RS) model with gauge fields in the bulk is dual to a (strongly coupled) 4D conformal field theory (CFT) with an UV cut-off and in which global symmetries of the CFT are gauged. We elucidate features of this dual CFT which are crucial for a complete understanding of the proposed duality. We ar
Ting-Wai Chiu
I show that the conventional formulations of lattice domain-wall fermion with any finite N_s (in the fifth dimension) do not preserve the chiral symmetry optimally and propose a new action which preserves the chiral symmetry optimally for any finite N_s.
Diana Vaman, Herman Verlinde
We present an improvement of the interacting string bit theory proposed in hep-th/0206059, designed to reproduce the non-planar perturbative amplitudes between BMN operators in N=4 gauge theory. Our formalism incorporates the effect of operator mixing and all non-planar corrections to the inner product. We use supersymmetry to construct the bosonic matrix el
M. Grazzini
We consider QCD corrections to Higgs boson production through gluon-gluon fusion in hadron collisions. We compute the effects of soft-gluon emission to all orders. We present numerical results at the Tevatron and the LHC.
Rennan Barkana, Abraham Loeb
Recent observations have shown that, only a billion years after the Big Bang, the Universe was already lit up by bright quasars fuelled by the infall of gas onto supermassive black holes. The masses of these early black holes are inferred from their luminosities to be > 10^9 solar masses, which is a difficult theoretical challenge to explain. Like nearby qua
Gregory Lawler, Oded Schramm, Wendelin Werner
We characterize and describe all random subsets $K$ of a given simply connected planar domain (the upper half-plane $\H$, say) which satisfy the ``conformal restriction'' property, i.e., $K$ connects two fixed boundary points (0 and $\infty$, say) and the law of $K$ conditioned to remain in a simply connected open subset $D$ of $\H$ is identical to t
Stefan Schwede, Brooke Shipley
We construct Quillen equivalences between the model categories of monoids (rings), modules and algebras over two Quillen equivalent model categories under certain conditions. This is a continuation of our earlier work where we established model categories of monoids, modules and algebras [Algebras and modules in monoidal model categories, Proc. London Math.