January 2006 arXiv papers — page 25

John Cardy

SLE(kappa,rho) is a generalisation of Schramm-Loewner evolution which describes planar curves which are statistically self-similar but not conformally invariant in the strict sense. We show that, in the context of boundary conformal field theory, this process arises naturally in models which contain a conserved U(1) current density J, in which case it gives

A. F. M. ter Elst, Derek W. Robinson, Yueping Zhu

We consider second-order partial differential operators $H$ in divergence form on $\Ri^d$ with a positive-semidefinite, symmetric, matrix $C$ of real $L_\infty$-coefficients and establish that $H$ is strongly elliptic if and only if the associated semigroup kernel satisfies local lower bounds, or, if and only if the kernel satisfies Gaussian upper and lower

Arun Ram

This paper makes precise the close connection between the affine Hecke algebra, the path model, and the theory of crystals. Section 2 is a basic pictorial exposition of Weyl groups and affine Weyl groups and Section 5 is an exposition of the theory of (a) symmetric functions, (b) crystals and (c) the path model. Sections 3 and 4 give an exposition of the aff

Daniele Del Santo, Martino Prizzi

We give sharp regularity conditions, ensuring the backward uniquess property to a class of parabolic operators.

Giovanni Felder, Andre Henriques, Carlo A. Rossi, Chenchang Zhu

The identities for elliptic gamma functions discovered by A. Varchenko and one of us are generalized to an infinite set of identities for elliptic gamma functions associated to pairs of planes in 3-dimensional space. The language of stacks and gerbes gives a natural framework for a systematic description of these identities and their domain of validity. A tr

Klaus Fleischmann, Vladimir A. Vatutin, Vitali Wachtel

Consider a critical Galton-Watson process Z={Z_n: n=0,1,...} of index 1+alpha, alpha in (0,1]. Let S_k(j) denote the sum of the Z_n with n in the window [k,...,k+j), and M_m(j) the maximum of the S_k with k moving in [0,m-j]. We describe the asymptotic behavior of the expectation EM_m(j) if the window width j=j_m is such that j/m converges in [0,1] as m tend

B. Brighi, J. -D. Hoernel

In this paper we investigate the similarity solutions of a plane mixed convection boundary layer flow near a semi-vertical plate, with a prescribed power law function of the distance from the leading edge for the temperature, that is embedded in a porous medium. We show the existence and uniqueness of convex and concave solutions for positive values of the p

Remi Leandre

We define measures on central extension of current groups in any dimension by using infinite dimensional Brownian motion.

Zoltan Buczolich

A universally L^1 good sequence n_k is constructed with n_{k+1}-n_k tending to infinity. For ergodic transformations non-conventional ergodic averages of L^1 functions computed by using this sequence converge to the integral of the function.

Matthieu Picantin

Divisibility monoids are a natural lattice-theoretical generalization of Mazurkiewicz trace monoids, namely monoids in which the distributivity of the involved divisibility lattices is kept as an hypothesis, but the relations between the generators are not supposed to necessarily be commutations. Here, we show that every divisibility monoid admits an explici

Eero Hyry, Yukio Nakamura, Lauri Ojala

In this article we investigate when a complete ideal in a two-dimensional regular local ring is a multiplier ideal of some ideal with an integral multiplying parameter. In particular, we show that this question is closely connected to the Gorenstein property of the blowup along the ideal.

Birgit Richter

The stabilization of Hochschild homology of commutative algebras is Gamma homology. We describe a cyclic variant of Gamma homology and prove that the associated analogue of Connes' periodicity sequence becomes almost trivial, because the cyclic version coincides with the ordinary version from homological degree two on. We offer an alternative explanation

Alexander Premet, Helmut Strade

Let L be a finite dimensional simple Lie algebra over an algebraically closed field of characteristic p>3. We prove in this paper that if all tori of maximal dimansion in the semisimple p-envelope of L are standard, the L is up to isomorphism either a Lie algebra of type A_n, B_n, C_n, D_n, E_6, E_7, E_8, F_4, G_2 or a filtered Lie algebra of Cartan type. Wh

Andreas Gathmann

Tropical algebraic geometry is an active new field of mathematics that establishes and studies some very general principles to translate algebro-geometric problems into purely combinatorial ones. This expository paper gives an introduction to these new techniques with a special emphasis on the recent applications to problems in enumerative geometry.

Jaroslaw Kosiorek, Andrzej Matras

We introduce two axioms in Laguerre geometry and prove that they provide a characterization of miquelian planes over fields of the characteristic different from 2. They allow to describe an involutory automorphism that sheds some new light on a Laguerre inversion as well as on a symmetry with respect to a pair of generators.

Enrico De Micheli, Giovanni Alberto Viano

In this paper we study a class of Hausdorff--transformed power series whose convergence is extremely slow for large values of the argument. We perform a Watson-type resummation of these expansions, and obtain, by the use of the Pollaczek polynomials, a new representation whose convergence is much faster. We can thus propose a new algorithm for the numerical

William Y. C. Chen, Kathy Q. Ji

We obtain a finite form of Jacobi's identity and present a combinatorial proof based on the structure of synchronized partitions.

A. F. M. ter Elst, Derek W. Robinson, Adam Sikora, Yueping Zhu

We consider properties of second-order operators $H = -\sum^d_{i,j=1} \partial_i \, c_{ij} \, \partial_j$ on $\Ri^d$ with bounded real symmetric measurable coefficients. We assume that $C = (c_{ij}) \geq 0$ almost everywhere, but allow for the possibility that $C$ is singular. We associate with $H$ a canonical self-adjoint viscosity operator $H_0$ and examin

K. T. -R. McLaughlin, A. H. Vartanian, X. Zhou

Let $Λ^{\mathbb{R}}$ denote the linear space over $\mathbb{R}$ spanned by $z^{k}$, $k \! \in \! \mathbb{Z}$. Define the real inner product (with varying exponential weights) $\langle \boldsymbol{\cdot},\boldsymbol{\cdot} \rangle_{\mathscr{L}} \colon Λ^{\mathbb{R}} \times Λ^{\mathbb{R}} \! \to \! \mathbb{R}$, $(f,g) \! \mapsto \! \int_{\mathbb{R}}f(s)g(s) \ex

Christian Krattenthaler

We put recent results by Chen, Deng, Du, Stanley and Yan on crossings and nestings of matchings and set partitions in the larger context of the enumeration of fillings of Ferrers shape on which one imposes restrictions on their increasing and decreasing chains. While Chen et al. work with Robinson-Schensted-like insertion/deletion algorithms, we use the grow

Shripad M. Garge

It is a theorem of Artin, Tits et al. that a finite simple group is determined by its order, with the exception of the groups (A_3(2), A_2(4)) and (B_n(q), C_n(q)) for n > 2, q odd. We investigate the situation for finite semisimple groups of Lie type. It turns out that the order of the finite group H(F_q) for a split semisimple algebraic group H defined ove

Jason Fox Manning

We prove some general results about quasi-actions on trees and define Property (QFA), which is analogous to Serre's Property (FA), but in the coarse setting. This property is shown to hold for a class of groups, including $SL(n,\Z)$ for $n\geq 3$. We also give a way of thinking about Property (QFA) by breaking it down into statements about particular cla

Hannu J. Rajaniemi

We explore the importance of the choice of spin structure in determining the amount of supersymmetry preserved by a symmetric M-theory background constructed by quotienting a supersymmetric Hpp-wave with a discrete subgroup in the centraliser of its isometry group.

Aurel Bulgac, Piotr Magierski, Andreas Wirzba

We present a simple formalism for the evaluation of the Casimir energy for two spheres and a sphere and a plane, in case of a scalar fluctuating field, valid at any separations. We compare the exact results with various approximation schemes and establish when such schemes become useful. The formalism can be easily extended to any number of spheres and/or pl

Tewodros Amdeberhan, Arvind Ayyer

Partial Isometries are important constructs that help give nontrivial solutions once a simple solution is known. We generalize this notion to Extended Partial Isometries and include operators which have right inverses but no left inverses (or vice versa). We find a large class of such operators and conjecture the moduli space to be the Hilbert Scheme of Poin

Pedro Castelo Ferreira

In this work are consider several topics in the Topological Membrane (TM) approach to string theory. The string dynamics is generated from the bulk physics, namely from the 3D Topologically Massive Gauge Theory (TMGT) and Topologically Massive Gravity (TMG). Both (equivalent) path integral and canonical methods of quantizing TMGT are studied. It is shown tha

A. B. Balantekin

Current experimental and observational limits on the neutrino magnetic moment are reviewed. Implications of the recent results from the solar and reactor neutrino experiments for the value of the neutrino magnetic moment are discussed. It is shown that spin-flavor precession in the Sun is suppressed.

Vincenzo Cirigliano, Benjamin Grinstein

We extend the effective theory of Minimal Lepton Flavor Violation (MLFV) by including four-lepton operators. We compute the rates for mu -> 3 e and tau -> 3 ell decays and point out several new ways to test the hypothesis of MLFV. We also investigate to what extent it will be possible from (future) experimental information to pin down the contributions of di

Jose A. Oller, Joaquim Prades, Michela Verbeni

In their Comment, Borasoy et al. [arXiv:hep-ph/0512279], criticize our results [PRL 95 (2005) 172502] that accommodate both scattering data and the new accurate measurement by DEAR of the shift and width of kaonic hydrogen. In our calculations we have employed unitary chiral perturbation theory (UCHPT). We discuss why their arguments are irrelevant or do not

A. Dainese, N. Armesto, M. Cacciari, C. A. Salgado

The attenuation of heavy-flavored particles in nucleus-nucleus collisions tests the microscopic dynamics of medium-induced parton energy loss and, in particular, its expected dependence on the identity (color charge and mass) of the parent parton. We discuss the comparison of theoretical calculations with recent single-electron data from RHIC experiments. Th

Zhi-zhong Xing, He Zhang

In a novel parametrization of neutrino mixing and in the approximation of $τ$-lepton dominance, we show that the one-loop renormalization-group equations (RGEs) of Dirac neutrinos are different from those of Majorana neutrinos even if two Majorana CP-violating phases vanish. As the latter can keep vanishing from the electroweak scale to the typical seesaw sc

Harald Fritzsch, Zhi-zhong Xing

We speculate that the mass spectrum of three neutrinos might have a normal hierarchy as that of three charged leptons or that of three up-type (or down-type) quarks. In this spirit, we propose a novel parametrization of the $3\times 3$ lepton flavor mixing matrix. Its mixing angles $θ_l$ and $θ_ν$ can be related to the mass ratios $m_e/m_μ$ and $m_1/m_2$ in

Johannes Hirn, Veronica Sanz

In this talk, an SU(Nf)xSU(Nf)Yang-Mills model with a compact extra-dimension is used to describe the spin-1 mesons and pions of massless QCD in the large-Nc. The right 4D symmetry and symmetry-breaking pattern is produced by imposing appropriate boundary conditions. The Goldstone boson fields are constructed using a Wilson line. We derive the low-energy lim

Masahiro Imachi, Yasuhiko Shinno, Hiroshi Yoneyama

The sign problem is notorious in Monte Carlo simulations of lattice QCD with the finite density, lattice field theory (LFT) with a $θ$ term and quantum spin models. In this report, to deal with the sign problem, we apply the maximum entropy method (MEM) to LFT with the $θ$ term and investigate to what extent the MEM is applicable to this issue. Based on this

P. Petroff, the CDF, D0 Collaboration

Measurements of inclusive W and Z cross sections times leptonic branching ratios for $p\bar p$ collisions at $\sqrt s$=1.96 TeV are reported here on behalf of the CDF and D0 collaborations. The data correspond t an integrated luminosity up to 200 $pb\_-1$. The ratio of leptonic W and Z rates is measured and the leptonic branching fraction $B(W \to \ellν)$ is

SciBooNE Collaboration

This document presents the physics case for bringing SciBar, the fully active, finely segmented tracking detector at KEK, to the FNAL Booster Neutrino Beam (BNB) line. This unique opportunity arose with the termination of K2K beam operations in 2005. The physics that can be done with SciBar/BNB can be put into three categories, each involving several measure

R. Arnold

The NEMO-3 tracking detector is located in the Fréjus Underground Laboratory. It was designed to study double beta decay in a number of different isotopes. Presented here are the experimental half-life limits on the double beta decay process for the isotopes $^{100}$Mo and $^{82}$Se for different Majoron emission modes and limits on the effective neutrino-Ma

V. Druzhinin

We present a review of BaBar results on e+e- annihilations into exclusive hadronic final states using the initial state radiation technique. Cross sections over the sqrt{s} range from threshold to 4.5 GeV, with very small point-to-point systematic errors, are presented for the 3pi, 2(pi+ pi-), 3(pi+ pi-), 2(pi+ pi-)2pi0, K+ K- pi+ pi-, 2(K+ K-) and p anti-p

Charles R. Keeton, A. O. Petters

We study gravitational lensing by compact objects in gravity theories that can be written in a Post-Post-Newtonian (PPN) framework: i.e., the metric is static and spherically symmetric, and can be written as a Taylor series in m/r, where m is the gravitational radius of the compact object. Working invariantly, we compute corrections to standard weak-deflecti

Francesco Cianfrani, Giovanni Montani

In this work we develop a geometrical unification theory for gravity and the electro-weak model in a Kaluza-Klein approach; in particular, from the curvature dimensional reduction Einstein-Yang-Mills action is obtained. We consider two possible space-time manifolds: 1)$V^{4}\otimes S^{1}\otimes S^{2}$ where isospin doublets are identified with spinors; 2) $V

Subhash Kak

This article considers evidence from physical and biological sciences to show machines are deficient compared to biological systems at incorporating intelligence. Machines fall short on two counts: firstly, unlike brains, machines do not self-organize in a recursive manner; secondly, machines are based on classical logic, whereas Nature's intelligence ma

Alex Vinokur

A Turing machine that computes Fibonacci numbers is described.

Tony Thomas, Arbind Kumar Lal

Artin's braid groups have been recently suggested as a new source for public-key cryptography. In this paper we propose the first undeniable signature schemes using the conjugacy problem and the decomposition problem in the braid groups which are believed to be hard problems.

L. P. Gor'kov, P. D. Grigoriev

Enormous mass enhancement at ''hot spots'' on the Fermi surface (FS) of CeIn$_3$ has been reported at strong magnetic field near its antiferromagnetic (AFM) quantum critical point [T. Ebihara et al., Phys. Rev. Lett. 93, 246401 (2004)] and ascribed to anomalous spin fluctuations at these spots. The ''hot spots'' lie at the pos

Z. Rapti, A. Smerzi, K. O. Rasmussen, A. R. Bishop

We have recently suggested that the probability for the formation of thermally activated DNA bubbles is, to a very good approximation, proportional to the number of soft AT pairs over a length L(n) that depend on the size $n$ of the bubble and on the temperature of the DNA. Here we clarify the physical interpretation of this length by relating it to the (hea

Axel Fingerle

Fluctuation Theorems are statements about the entropy of systems far from thermal equilibrium. In this Letter relativistic Fluctuation Theorems for Brownian motion are presented and proven. Though there is a known discretization dilemma leading to a certain class of Brownian processes, the Fluctuation Theorems are shown to cover the entire class, and to dete

Hyeonjin Doh, Nir Friedman, Hae-Young Kee

An electronic nematic phase can be classified by a spontaneously broken discrete rotational symmetry of a host lattice. In a square lattice, there are two distinct nematic phases. The parallel nematic phase breaks $x$ and $y$ symmetry, while the diagonal nematic phase breaks the diagonal $(x+y)$ and anti-diagonal $(x-y)$ symmetry. We investigate the interpla

Titus Sandu, Athanasios Chantis, Radu Iftimie

Spin-dependent tunneling through an indirect bandgap barrier like the GaAs/AlAs/GaAs heterostructure along [001] direction is studied by the tight-binding method. The tunneling is characterized by the proportionality of the Dresselhaus Hamiltonians at $Γ$ and $X$ points in the barrier and by Fano resonances. The present results suggest that large spin polari

G. Giupponi, J. Harting, P. V. Coveney

We use a lattice Boltzmann (LB) kinetic scheme for modelling amphiphilic fluids that correctly predicts rheological effects in flow. No macroscopic parameters are included in the model. Instead, three-dimensional hydrodynamic and rheological effects are emergent from the underlying particulate conservation laws and interactions. We report evidence of shear t

Mika Sillanpaa, Leif Roschier, Teijo Lehtinen, Pertti Hakonen

Low-frequency susceptibility of the split Cooper-pair box (SCPB) is investigated for use in sensitive measurements of external phase or charge. Depending on the coupling scheme, the box appears as either inductive or capacitive reactance which depends on external phase and charge. While coupling to the source-drain phase, we review how the SCPB looks like a

Jean-Pascal Rueff, M. Calandra, M. D'astuto, Ph. Leininger

We report on first investigation of the lattice dynamics in the novel superconducting material Na$\_{0.35}$CoO$\_2$$\cdot$1.3H$\_2$O and the non-hydrated parent compound Na$\_{0.7}$CoO$\_2$ by inelastic x-ray scattering. The measured phonon dispersion along the $Γ-M$ direction show a marked softening with hole doping of two optical phonon branches close to t

Olaf Stenull, T. C. Lubensky

We present a theory for the low-frequency, long-wavelength dynamics of soft smectic-C elastomers with locked-in smectic layers. Our theory, which goes beyond pure hydrodynamics, predicts a dynamic soft elasticity of these elastomers and allows us to calculate the storage and loss moduli relevant for rheology experiments as well as the mode structure.

Andrea Gauzzi, Neven Barišic, Francesca Licci, Gianluca Calestani

Resistivity under pressure and magnetization measurements on Ba$_{1-x}$Sr$_x$VS$_3$ single crystals with 0 $\leq x \leq$ 0.18 and no sulphur deficiency show an abrupt onset of ferromagnetic (FM) order at a critical value $x$=0.07, concomitant to a change of the magnetic properties at the metal-insulator transition (MIT) and to a collapse of the unit cell at

Zhenghan Wang

We discuss a nexus among quantum topology, quantum physics and quantum computing.

M. Pica Ciamarra, M. D. De Vizia, A. Fierro, M. Tarzia

We present extensive Molecular Dynamics simulations on species segregation in a granular mixture subject to vertical taps. We discuss how grain properties, e.g., size, density, friction, as well as, shaking properties, e.g., amplitude and frequency, affect such a phenomenon. Both Brazil Nut Effect (larger particles on the top, BN) and the Reverse Brazil Nut

Jeppe C. Dyre

We first review the phenomenology of viscous liquids and the standard models used for explaining the non-Arrhenius average relaxation time. Then the focus is turned to the so-called elastic models, arguing that these models are all equivalent in the Einstein approximation (where the short-time elastic properties are all determined by just one effective, temp

Y. Nakajima, K. Izawa, Y. Matsuda, K. Behnia

We report on the pressure dependence of the Hall coefficient $R_H$ in quasi-2D heavy fermion CeCoIn$_5$. At ambient pressure, below a temperature associated with the emergence of non-Fermi liquid properties, $R_H$ is anomalously enhanced. We found that the restoration of the Fermi liquid state with applied pressure leads to a gradual suppression of this dram

K. B. K. Mayya, R. E. Amritkar

We construct and analyze symmetrized delay correlation matrices for empirical data sets for atmopheric and financial data to derive information about correlation between different entities of the time series over time. The information about correlations is obtained by comparing the results for the eigenvalue distribution with the analytical results for the i

R. D. R. Bhat, J. E. Sipe

Quantum interference between one- and two-photon absorption pathways allows coherent control of interband transitions in unbiased bulk semiconductors; carrier population, carrier spin polarization, photocurrent injection, and spin current injection can all be controlled. We calculate injection spectra for these effects using a 14x14 k.p Hamiltonian including

F. F. Sizov, I. O. Lysiuk, J. V. Gumenjuk-Sichevska, S. G. Bunchuk

Investigations of electrical properties of long-wavelength infrared (LWIR) mercury cadmium telluride (MCT) arrays exposed to gamma-radiation have been performed. Resistance-area product characteristics of LWIR n{+}-p photodiodes have been investigated using microprobe technique at T=78 K before and after an exposure to various doses of gamma-radiation. The c

U. Buchenau, M. Ohl, A. Wischnewski

Literature dielectric data of glycerol, propylene carbonate and ortho-terphenyl (OTP) show that the measured dielectric relaxation is a decade faster than the Debye expectation, but still a decade slower than the breakdown of the shear modulus. From a comparison of time scales, the dielectric relaxation seems to be due to a process which relaxes not only the

Anastasios Malakis, Nikolaos G. Fytas

We apply the recently developed critical minimum energy subspace scheme for the investigation of the random-field Ising model. We point out that this method is well suited for the study of this model. The density of states is obtained via the Wang-Landau and broad histogram methods in a unified implementation by employing the N-fold version of the Wang-Landa

Boris Kastening

The fluctuation pressure that an infinitely extended fluid membrane exerts on two enclosing parallel hard walls is computed. Variational perturbation theory is used to extract the hard-wall limit from a perturbative expansion through six loops obtained with a smooth wall potential. Our result alpha=0.0821+/-0.0005 for the constant conventionally parametrizin

T. Tohyama

Symmetry of photoexcited states with two photoinduced carriers in two-dimensional Mott insulators is examined by applying the numerically exact diagonalization method to finite-size clusters of a half-filled Hubbard model in the strong-coupling limit. The symmetry of minimum-energy bound state is found to be s-wave, which is different from a d_{x^2-y^2} wave

Reghan J. Hill

A theoretical model of electromigrative, diffusive and convectivetransport polymer-gel composites is presented. Bulk properties are derived from the standard electrokinetic model with an impenetrable charged sphere embedded in an electrolyte-saturated Brinkman medium. Because the microstructure can be carefully controlled, these materials are promising candi

Mukremin Kilic, Ted von Hippel, Fergal Mullally, William T. Reach

We present 4.5$μ$m and 8$μ$m photometric observations of 18 cool white dwarfs obtained with the Spitzer Space Telescope. Our observations demonstrate that four white dwarfs with T_eff< 6000 K show slightly depressed mid-infrared fluxes relative to white dwarf models. In addition, another white dwarf with a peculiar optical and near-infrared spectral energy d

M. Vestergaard, B. M. Peterson

We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy. These mass-scaling relationships between line widths and luminosity are based on recently improved empirical relationships between the broad-line region size

E. T. Young, P. S. Teixeira, C. J. Lada, J. Muzerolle

We analyze {\it Spitzer} and Magellan observations of a star forming core near IRS-2 in the young cluster NGC 2264. The submillimeter source IRAS 12 S1, previously believed to be an intermediate mass Class 0 object is shown to be a dense collection of embedded, low mass stars. We argue that this group of stars represents the fragmenting collapse of a dense,

Alain Coc, Keith A. Olive, Jean-Philippe Uzan, Elisabeth Vangioni

We investigate BBN in scalar-tensor theories of gravity with arbitrary matter couplings and self-interaction potentials. We first consider the case of a massless dilaton with a quadratic coupling to matter. We perform a full numerical integration of the evolution of the scalar field and compute the resulting light element abundances. We demonstrate in detail

J. Lavalle, H. Manseri, A. Jacholkowska, E. Brion

If dark matter is made of neutralinos, annihilation of such Majorana particles should produce high energy cosmic rays, especially in galaxy halo high density regions like galaxy centres. M31 (Andromeda) is our nearest neighbour spiral galaxy, and both its high mass and its low distance make it a source of interest for the indirect search for dark matter thro

L. van Starkenburg, P. P. van der Werf, L. Yan, A. F. M. Moorwood

The evolution of the line width - luminosity relation for spiral galaxies, the Tully-Fisher relation, strongly constrains galaxy formation and evolution models. At this moment, the kinematics of z>1 spiral galaxies can only be measured using rest frame optical emission lines associated with star formation, such as Halpha and [OIII]5007/4959 and [OII]3727. Th

Joseph C. Weingartner, B. T. Draine, David K. Barr

Photoelectric emission from dust plays an important role in grain charging and gas heating. To date, detailed models of these processes have focused primarily on grains exposed to soft radiation fields. We provide new estimates of the photoelectric yield for neutral and charged carbonaceous and silicate grains, for photon energies exceeding 20 eV. We include

A. Cattaneo, A. Dekel, J. Devriendt, B. Guiderdoni

We reproduce the blue and red sequences in the observed joint distribution of colour and magnitude for galaxies at low and high redshifts using hybrid N-body/semi-analytic simulations of galaxy formation. The match of model and data is achieved by mimicking the effects of cold flows versus shock heating coupled to feedback from active galactic nuclei (AGNs),

M. S. Lewis, W. M. Liu, N. E. Q. Paust, Brian Chaboyer

We present new photometry for the Galactic thick disk globular cluster Palomar 11 extending well past the main sequence turn-off in the V and I bands. This photometry shows noticeable red giant and subgiant branches. The difference in magnitude between the red horizontal branch (red clump) and the subgiant branch is used to determine that Palomar 11 has an a

E. Maiorano, N. Masetti, E. Palazzi, S. Savaglio

We here report on the photometric, spectroscopic and polarimetric monitoring of the optical afterglow of the Gamma-Ray Burst (GRB) 030328 detected by HETE-2. We found that a smoothly broken power-law decay provides the best fit of the optical light curves, with indices alpha_1 = 0.76 +/- 0.03, alpha_2 = 1.50 +/- 0.07, and a break at t_b = 0.48 +/- 0.03 d aft

Genevieve Soucail, Giovanni Covone, Jean-Paul Kneib

We present an integral field spectroscopy survey of rich clusters of galaxies aimed at studying their lensing properties. Thanks to knowledge of the spectroscopic caracteristics of more than three families of multiple images in a single lens, one is able in principle to derive constraints on the geometric cosmological parameters. We show that this ambitious

A. D. Erlykin, A. W. Wolfendale

We study the effect of the stochastic character of supernova explosions on the anisotropy of galactic cosmic rays below the knee. We conclude that if the bulk of cosmic rays are produced in supernova explosions the observed small and nearly energy independent amplitude of the anisotropy and its phase are to the large extent determined by the history of these

Mercedes Lopez-Morales

This paper summarizes a three night observing campaign aimed at achieving milli-magnitude precision photometry of bright stars (V < 9.0) with the 1-meter Swope telescope at Las Campanas Observatory. The test targets were the main sequence stars HD205739 and HD135446. The results show that, by placing a concentric diaphragm in front of the aperture of the tel

Benjamin F. Williams, S. Naik, Michael R. Garcia, Paul J. Callanan

From October 1999 to August 2002, 45 transient X-ray sources were detected in M31 by Chandra and XMM-Newton. We have performed spectral analysis of all XMM-Newton and Chandra ACIS detections of these sources, as well as flux measurements of Chandra HRC detections. The result is absorption-corrected X-ray lightcurves for these sources covering this 2.8 year p

A. Merloni, E. Koerding, S. Heinz, S. Markoff

The fundamental plane of black hole activity is a non-linear correlation among radio core luminosity, X-ray luminosity and mass of all accreting black holes, both of stellar mass and supermassive, found by Merloni, Heinz and Di Matteo (2003) and, independently, by Falcke, Koerding and Markoff (2004). Here we further examine a number of statistical issues rel

G. Giovannini, L. Feretti, F. Govoni, M. Murgia

We present here new images of relics and halo sources in rich cluster of galaxies and the correlation between the halo radio surface brightness versus the cluster bolometric X-ray luminosity.

Brian Warner, Patrick A. Woudt

We present new observations of the rapid oscillations in the dwarf nova VW Hyi, made late in outburst. These dwarf nova oscillations (DNOs) increase in period until they reach 33 s, when a transition to a strong 1st harmonic and weak fundamental takes place. After further period increase the 2nd harmonic appears; often all three components are present simult

F. Sabbadin, M. Turatto, R. Ragazzoni, E. Cappellaro

This paper - the first of a short series dedicated to the long-stan ding astronomical problem of de-projecting the bi-dimensional apparent morpholog y of a three-dimensional mass of gas - focuses on the density distribution in real Planetary Nebulae (and all types of expanding nebulae). We introduce some basic theoretical notions, discuss the observational m

Hajime Sotani, Takayuki Tatekawa

For the evolution of density fluctuation in nonlinear cosmological dynamics, adhesion approximation (AA) is proposed as a phenomenological model, which is especially useful for describing nonlinear evolution. However, the origin of the artificial viscosity in AA is not clarified. Recently, Buchert and Dom\&#39;ınguez report if the velocity dispersion of the

Donald G. York, Pushpa Khare, Daniel Vanden Berk, Varsha P. Kulkarni

We have studied a sample of 809 Mg II absorption systems with 1.0 < z_abs < 1.86 in the spectra of SDSS QSOs, with the aim of understanding the nature and abundance of the dust and the chemical abundances in the intervening absorbers. Normalized, composite spectra were derived, for abundance measurements, for the full sample and several sub-samples, chosen o

Neal Dalal, Daniel E. Holz, Scott A. Hughes, Bhuvnesh Jain

Observations of the gravitational radiation from well-localized, inspiraling compact object binaries can measure absolute source distances with high accuracy. When coupled with an independent determination of redshift through an electromagnetic counterpart, these standard sirens can provide an excellent probe of the expansion history of the Universe and the

Kristian Pedersen, Jesper Rasmussen, Jesper Sommer-Larsen, Sune Toft

Hot gaseous haloes surrounding galaxies and extending well beyond the distribution of stars are a ubiquitous prediction of galaxy formation scenarios. The haloes are believed to consist of gravitationally trapped gas with a temperature of millions of Kelvin. The existence of such hot haloes around massive elliptical galaxies has been established through thei

Eyal Markman

Let M be a 2n-dimensional Kahler manifold deformation equivalent to the Hilbert scheme of length n subschemes of a K3 surface S. Let Mon be the group of automorphisms of the cohomology ring of M, which are induced by monodromy operators. The second integral cohomology of M is endowed with the Beauville-Bogomolov bilinear form. We prove that the restriction h

Tom H. Koornwinder

An explicit structure relation for Askey-Wilson polynomials is given. This involves a divided q-difference operator which is skew symmetric with respect to the Askey-Wilson inner product and which sends polynomials of degree n to polynomials of degree n+1. By specialization of parameters and by taking limits, similar structure relations, as well as lowering

Richard Easther, William H. Kinney, Brian A. Powell

We derive an extended version of the well-known Lyth Bound on the total variation of the inflaton field, incorporating higher order corrections in slow roll. We connect the field variation $Δϕ$ to both the spectral index of scalar perturbations and the amplitude of tensor modes. We then investigate the implications of this bound for ``small field&#39;&#39; p

Prashant, Indranil Chakrabarty

The paper is taken out with immediate effect.

Marcelo Aparecido Marchiolli

Adopting the framework of the Jaynes-Cummings model with an external quantum field, we obtain exact analytical expressions of the normally ordered moments for any kind of cavity and driving fields. Such analytical results are expressed in the integral form, with their integrands having a commom term that describes the product of the Glauber-Sudarshan quasipr

Y. Tokiwa, T. Radu, R. Coldea, H. Wilhelm

We report magnetization and specific heat measurements in the 2D frustrated spin-1/2 Heisenberg antiferromagnet Cs2CuCl4 at temperatures down to 0.05 K and high magnetic fields up to 11.5 T applied along a, b and c-axes. The low-field susceptibility chi (T) M/B shows a broad maximum around 2.8 K characteristic of short-range antiferromagnetic correlations an

B. Kyung, G. Kotliar, A. -M. S. Tremblay

We study the Hubbard model using the Cellular Dynamical Mean-Field Theory (CDMFT) with quantum Monte Carlo (QMC) simulations. We present the algorithmic details of CDMFT with the Hirsch-Fye QMC method for the solution of the self-consistently embedded quantum cluster problem. We use the one- and two-dimensional half-filled Hubbard model to gauge the performa

Olga Kravchenko

Structures of Lie algebras, Lie coalgebras, Lie bialgebras and Lie quasibialgebras are presented as solutions of Maurer-Cartan equations on corresponding governing differential graded Lie algebras using the big bracket construction of Kosmann-Schwarzbach. This approach provides a definition of an $L_\infty$-(quasi)bialgebra (strongly homotopy Lie (quasi)bial

Pablo Mora, Rodrigo Olea, Ricardo Troncoso, Jorge Zanelli

A gauge invariant action principle, based on the idea of transgression forms, is proposed. The action extends the Chern-Simons form by the addition of a boundary term that makes the action gauge invariant (and not just quasi-invariant). Interpreting the spacetime manifold as cobordant to another one, the duplication of gauge fields in spacetime is avoided. T

A. M. Beloborodov, Y. Levin, F. Eisenhauer, R. Genzel

Two disks of young stars have recently been discovered in the Galactic Center. The disks are rotating in the gravitational field of the central black hole at radii r=0.1-0.3 pc and thus open a new opportunity to measure the central mass. We find that the observed motion of stars in the clockwise disk implies M=4.3+/-0.5 million solar masses for the fiducial

Daniel Proga, Bing Zhang

We consider the properties of a hyperaccretion model for gamma-ray bursts (GRBs) at the late time when the mass supply rate is expected to decrease with time. We point out that the region in the vicinity of the accretor and the accretor itself can play an important role in determining the rate and time behavior of the accretion and ultimately the energy outp

David Langlois, Filippo Vernizzi

We develop a covariant formalism to study nonlinear perturbations of dissipative and interacting relativistic fluids. We derive nonlinear evolution equations for various covectors defined as linear combinations of the spatial gradients of the local number of e-folds and of some scalar quantities characterizing the fluid, such as the energy density or the par

L. Girardello, A. Mariotti, G. Tartaglino-Mazzucchelli

We investigate the Dijkgraaf-Vafa proposal when supersymmetry is broken. We consider U(N) SYM with chiral adjoint matter where the coupling constants in the tree-level superpotential are promoted to chiral spurions. The holomorphic part of the low-energy glueball superpotential can still be analyzed. We compute the holomorphic supersymmetry breaking contribu