March 2008 arXiv papers — page 16

M. Puech, H. Flores, F. Hammer, Y. Yang

Using the multi-integral field spectrograph GIRAFFE at VLT, we have derived the K-band Tully-Fisher relation (TFR) at z~0.6 for a representative sample of 65 galaxies with emission lines. We confirm that the scatter in the z~0.6 TFR is caused by galaxies with anomalous kinematics, and find a positive and strong correlation between the complexity of the kinem

Jeroen van den Brink, Daniel I. Khomskii

In this contribution to the special issue on multiferroics we focus on multiferroicity driven by different forms of charge ordering. We will present the generic mechanisms by which charge ordering can induce ferroelectricity in magnetic systems. There is a number of specific classes of materials for which this is relevant. We will discuss in some detail $(i)

S. Groote, H. Veermäe

Coupled map lattices are a paradigm of higher-dimensional dynamical systems exhibiting spatio-temporal chaos. A special case of non-hyperbolic maps are one-dimensional map lattices of coupled Chebyshev maps with periodic boundary conditions, called chaotic strings. In this short note we show that the fine structure of the self energy of this chaotic string i

Peer-Olaf Siebers, Uwe Aickelin, Giuliana Battisti, Helen Celia

There is no doubt that management practices are linked to the productivity and performance of a company. However, research findings are mixed. This paper provides a multi-disciplinary review of the current evidence of such a relationship and offers suggestions for further exploration. We provide an extensive review of the literature in terms of research find

Pau Figueras, Hari K Kunduri, James Lucietti, Mukund Rangamani

We consider extremal black hole solutions to the vacuum Einstein equations in dimensions greater than five. We prove that the near-horizon geometry of any such black hole must possess an SO(2,1) symmetry in a special case where one has an enhanced rotational symmetry group. We construct examples of vacuum near-horizon geometries using the extremal Myers-Perr

HERMES Collaboration, A. Airapetian

The momentum and helicity density distributions of the strange quark sea in the nucleon are obtained in leading order from charged-kaon production in deep-inelastic scattering on the deuteron. The distributions are extracted from spin-averaged K+/- multiplicities, and from K+/- and inclusive double-spin asymmetries for scattering of polarized positrons by a

Sabin Cautis, Timothy Logvinenko

We propose a three dimensional generalization of the geometric McKay correspondence described by Gonzales-Sprinberg and Verdier in dimension two. We work it out in detail when G is abelian and C^3/G has a single isolated singularity. More precisely, we show that the Bridgeland-King-Reid derived category equivalence induces a natural geometric correspondence

Eric A. Bergshoeff, Olaf Hohm, Teake A. Nutma

We determine the gauge symmetries of all p-forms in maximal three-dimensional gauged supergravity by requiring invariance of the Lagrangian. It is shown that in a particular ungauged limit these symmetries are in precise correspondence to those predicted by the very-extended Kac-Moody algebra E11. We demonstrate that whereas in the ungauged limit the bosonic

Ning Bo Zhao, An Min Wang

We investigate the local implementation of nonlocal operations with the block matrix form, and propose a protocol for any diagonal or offdiagonal block operation. This method can be directly generalized to the two-party multiqubit case and the multiparty case. Especially, in the multiparty cases, any diagonal block operation can be locally implemented using

Bruno Carneiro da Cunha

The collective behavior of the SL(2,R) covariant brane states of non-critical c=1 string theory found in a previous work, is studied in the Fermi liquid approximation. It is found that such states mimick the coset WZW model, whereas only by further restrictions one recovers the double-scaling limit which was purported to be equivalent to closed string models

Wojciech Krolikowski

In the discussed model, the cold dark matter consists of Dirac spin-1/2 fermions, sterile from all Standard Model charges, where masses are generated by a nonzero vacuum expectation value of a field of scalar bosons, also assumed to be sterile. For convenience, these sterile particles have beeen called sterinos and sterons, respectively. It has been conjectu

Uwe Aickelin, Jingpeng Li

Schedules can be built in a similar way to a human scheduler by using a set of rules that involve domain knowledge. This paper presents an Estimation of Distribution Algorithm (eda) for the nurse scheduling problem, which involves choosing a suitable scheduling rule from a set for the assignment of each nurse. Unlike previous work that used Genetic Algorithm

Angelo V. Caldarella, Anna Maria Pastore

We study manifolds endowed with mixed metric 3--contact structures, proving that the distribution spanned by the Reeb vector fields is integrable, with totally geodesic integral manifolds, of constant sectional curvature $k=\pm1$. We also prove a result of projectability of such structures onto paraquaternionic Kählerian structures.

H. Kleinert, P. Kienle

We show that the recent observation of the time modulation of two-body weak decays of heavy ions reveals the mass content of the electron neutrinos via interference patterns in the recoiling ion wave function. From the modulation period we derive the difference of the square masses $ Δm^2\approx 22.5\times 10^{-5}$ eV${}^2$, which is about 2.8 times larger t

Uwe Aickelin, Jamie Twycross, Thomas Hesketh-Roberts

Intrusion Detection Systems (ids)provide an important layer of security for computer systems and networks, and are becoming more and more necessary as reliance on Internet services increases and systems with sensitive data are more commonly open to Internet access. An ids responsibility is to detect suspicious or unacceptable system and network activity and

N. N. Achasov, A. A. Kozhevnikov

The cross section of reaction e^+e^-\toπ^+π^-π^+π^- is calculated for energies 0.65\leq \sqrt{s}\leq1 GeV in the framework of the generalized hidden local symmetry model. The calculations are compared with the data of CMD-2 and BaBaR. It is shown that the inclusion of heavy isovector resonances ρ(1450) and ρ(1700) is necessary for reconciling calculations wi

Steve Cayzer, Uwe Aickelin

The immune system is a complex biological system with a highly distributed, adaptive and self-organising nature. This paper presents an Artificial Immune System (AIS) that exploits some of these characteristics and is applied to the task of film recommendation by Collaborative Filtering (CF). Natural evolution and in particular the immune system have not bee

U. Ellwanger, C. -C. Jean-Louis, A. M. Teixeira

We investigate various classes of Gauge Mediated Supersymmetry Breaking models and show that the Next-to-Minimal Supersymmetric Standard Model can solve the mu-problem in a phenomenologically acceptable way. These models include scenarios with singlet tadpole terms, which are phenomenologically viable, e.g., in the presence of a small Yukawa coupling <~ 10^{

Wilberd van der Kallen

Prompted by an exercise in the Brion Kumar book on Frobenius splittings, we show compatibility with a few more subvarieties of the Frobenius splitting from our 1992 paper.

Cédric Lejard

Analytic continuation of viscous shock solution for the generalized Burgers equation with polynomial nonlinear source term is investigated. We show that a pertubated wave recovers its analyticity in the space variable in the strip limited by the first pair of singularities of the wave.

A. Deandrea, A. Nehme, P. Talavera

We provide a model-independent determination of the quantity B_0(m_d-m_u). Our approach rests only on chiral symmetry and data from the decay of the eta into three neutral pions. Since the low-energy prediction at next-to-leading order fails to reproduce the experimental results, we keep the strong interaction correction as an unknown parameter. As a first s

Lenka Zdeborová, Marc Mézard

We introduce and study the random &#34;locked&#34; constraint satisfaction problems. When increasing the density of constraints, they display a broad &#34;clustered&#34; phase in which the space of solutions is divided into many isolated points. While the phase diagram can be found easily, these problems, in their clustered phase, are extremely hard from the

Rajendra Bhandari

We first derive the round-trip Jones matrix for double passage through a reciprocal optical medium by means of reflection off a plane mirror that could be optically anisotropic. We then show that if a medium with only linear birefringence and linear dichroism is placed between a pair of orthogonal quarterwave plates with principal axes at 45 deg to that of t

Andreas Laeuchli, Corinna Kollath

We investigate the spreading of information in a one-dimensional Bose-Hubbard system after a sudden parameter change. In particular, we study the time-evolution of correlations and entanglement following a quench. The investigated quantities show a light-cone like evolution, i.e. the spreading with a finite velocity. We discuss the relation of this veloctiy

Mokhtar Hassaine, Cristian Martinez

We obtain electrically charged black hole solutions of the Einstein equations in arbitrary dimensions with a nonlinear electrodynamics source. The matter source is deriving from a Lagrangian given by an arbitrary power of the Maxwell invariant. The form of the general solution suggests a natural partition for the different ranges of this power. For a particu

E. H Saidi, A. Segui

We study the attractor mechanism of dual pairs of black brane bounds in N=2 supergravity in six and seven dimensions. First, we consider the effective potentials of the 6D and 7D black branes as well as their entropies. The contribution coming from the SO(1,1) factor of the moduli spaces M_{6D} and M_{7D} of these theories is carefully analyzed and it is use

A. A. Kochanov, T. S. Sinegovskaya, S. I. Sinegovsky

A new calculation of the atmospheric fluxes of cosmic-ray hadrons and muons in the energy range 10-10^5 GeV has been performed for the set of hadron production models, EPOS 1.6, QGSJET II-03, SIBYLL 2.1, and others that are of interest to cosmic ray physicists. The fluxes of secondary cosmic rays at several levels in the atmosphere are computed using directl

Chuan-Hung Chen, Hai-Yang Cheng, Yu-Kuo Hsiao

The channel $D_s^+\to p\bar n$ is the only kinematically allowed baryonic D decay. It proceeds solely through the W-annihilation topology. Hence, a recent observation of this mode by CLEO will shed light on the dynamics of W-annihilation. At the short-distance level, its branching ratio is very small, of order $10^{-6}$, owing to chiral suppression. It recei

Xiaoguang Wang, Zhe Sun, Z. D. Wang

We introduce the operator fidelity and propose to use its susceptibility for characterizing the sensitivity of quantum systems to perturbations. Two typical models are addressed: one is the transverse Ising model exhibiting a quantum phase transition, and the other is the one dimensional Heisenberg spin chain with next-nearest-neighbor interactions, which ha

Enno Middelberg, Uwe Bach

Very Long Baseline Interferometry, or VLBI, is the observing technique yielding the highest-resolution images today. Whilst a traditionally large fraction of VLBI observations is concentrating on Active Galactic Nuclei, the number of observations concerned with other astronomical objects such as stars and masers, and with astrometric applications, is signifi

Bibekananda Nayak, Lambodar Prasad Singh

The present day accelerated expansion of the universe is naturally addressed within the Brans-Dicke theory just by using holographic dark energy model with inverse of Hubble scale as IR cutoff. It is also concluded that if the universe continues to expand, then one day it might be completely filled with dark energy.

S. N. Dolya

We suggest a systematic method of extension of quasi-exactly solvable (QES) systems. We construct finite-dimensional subspaces on the basis of special functions (hypergeometric, Airy, Bessel ones) invariant with respect to the action of differential operators of the second order with polynomial coefficients. As a example of physical applications, we show tha

BES Collaboration, M. Ablikim

Using a sample of 14 million $\psip$ events collected with the BESII detector, branching fractions or upper limits on the branching fractions of $\psip$ decays into $γ\ppb$, $γ2(\pip\pim)$, $γ\kskp$, $γ\kap\kam\pip\pim$, $γ\kstarz\kam\pip+c.c.$, $γ\kstarz \kstarzb$, $γ\pip\pim\ppb$, $\gamma2(\kap\kam)$, $\gamma3(\pip\pim)$ and $\gamma2(\pip\pim)\kap\kam$ wit

Lee Smolin

A simple cubic matrix model is presented, which has truncations that, it is argued, lead at the classical level to a variety of theories of gauge fields and gravity. These include Chern-Simons theory in d=3, and BF theory and general relativity in d=4. General relativity coupled to Yang-mills theory for any SU(N) may also arise from quantum corrections. On t

E. Toth, A. M. Rey, P. B. Blakie

In this paper we develop a theoretical description of the correlations between ultra-cold bosons after free expansion from confinement in an optical lattice. We consider the system evolution during expansion and give criteria for a far field regime. We develop expressions for first and second order two-point correlations based on a variety of commonly used a

Travis R. Beals, Barry C. Sanders

We introduce a simple, practical approach with probabilistic information-theoretic security to mitigate one of quantum key distribution&#39;s major limitations: the short maximum transmission distance (~200 km) possible with present day technology. Our scheme uses classical secret sharing techniques to allow secure transmission over long distances through a

Alessio Figalli, Ludovic Rifford

We study the optimal transport problem in sub-Riemannian manifolds where the cost function is given by the square of the sub-Riemannian distance. Under appropriate assumptions, we generalize Brenier-McCann&#39;s Theorem proving existence and uniqueness of the optimal transport map. We show the absolute continuity property of Wassertein geodesics, and we addr

Alexander Raichev, Mark C. Wilson

Let $\sum_{\beta\in\nats^d} F_\beta x^\beta$ be a multivariate power series. For example $\sum F_\beta x^\beta$ could be a generating function for a combinatorial class. Assume that in a neighbourhood of the origin this series represents a nonentire function $F=G/H^p$ where $G$ and $H$ are holomorphic and $p$ is a positive integer. Given a direction $\alpha\

Yun Soo Myung, Min-Gyun Seo

We investigate the origin of holographic dark energy models which were recently proposed to explain the dark energy-dominated universe. For this purpose, we introduce the spacetime foam uncertainty of $δl \ge l_{\rm p}^αl^{α-1}$. It was argued that the case of $α=2/3$ could describe the dark energy with infinite statistics, while the case of $α=1/2$ can desc

Kunio Ishida, Keiichiro Nasu

We study the dynamics of quantum pattern formation processes in molecular crystals which is a concomitant with photoinduced nucleation. Since the nucleation process in coherent regime is driven by the nonadiabatic transition in each molecule followed by the propagation of phonons, it is necessary to take into account the quantum nature of both electrons and

Robert Fernholz, Ioannis Karatzas, Constantinos Kardaras

A financial market is called &#34;diverse&#34; if no single stock is ever allowed to dominate the entire market in terms of relative capitalization. In the context of the standard Ito-process model initiated by Samuelson (1965) we formulate this property (and the allied, successively weaker notions of &#34;weak diversity&#34; and &#34;asymptotic weak diversi

Myungshin Im, Induk Lee, Yunseok Cho, Changsu Choi

We report the discovery of 40 bright quasars and active galactic nuclei (AGNs) at low Galactic latitude (b<20deg). The low Galactic latitude region has been considered a place to avoid when searching for extragalactic sources, because of the high Galactic extinction, as well as a large number of stars contaminating the sample selection. Bright quasars (R<~17

Charles P. Strehlow, M. C. Sullivan

The suspension and levitation of superconductors by permanent magnets is one of the most fascinating consequences of superconductivity, and a wonderful instrument for generating interest in low temperature physics and electrodynamics. We present a novel classroom demonstration of the levitation/suspension of a superconductor over a magnetic track that maximi

Ian Agol

We show that there are at most finitely many one cusped orientable hyperbolic 3-manifolds which have more than eight non-hyperbolic Dehn fillings. Moreover, we show that determining these finitely many manifolds is decidable.

Mladen Georgiev

We propose a global symmetry-breaking mechanism based on an extension of the vibronic (cooperative Jahn-Teller) effects (comprising electron-phonon superpartners) to generalize them into fermion-boson superpartners. Examples of superpairs are constructed by combining phonons, photons, pi-mesons, etc. with electrons, holes, nucleons, etc. in condensed and nuc

M. Gersbach, D. L. Boiko, C. Niclass, C. Petersen

A system for time-correlated single photon counting applications based on CMOS single photon avalanche diodes is presented. An instrument response function of 79 ps allows a fluorescence decay of high-affinity Ca2+ indicator Oregon Green BAPTA-1 to be analyzed with unprecedented temporal resolution in the two-photon excitation regime. A triple exponential de

Stephen S. Eikenberry

Upon commissioning on Gemini South, FLAMINGOS-2 will be one of the most powerful wide-field near-infrared imagers and multi-object spectrographs ever built for use on 8-meter-class telescopes. In order to take best advantage of the strengths of FLAMINGOS-2 early in its life cycle, the instrument team has proposed to use 21 nights of Gemini guaranteed time in

S. Nicholas Raines, Stephen S. Eikenberry, Reba M. Bandyopadhyay

FLAMINGOS-2 (PI: S. Eikenberry) is a $5M facility-class near-infrared (1-2.5 micron) multi-object spectrometer and wide-field imager being built at the University of Florida for Gemini South. Here we highlight the capabilities of FLAMINGOS-2, as it will be an ideal instrument for surveying the accreting binary population in the Galactic Center.

D. J. Reilly, J. M. Taylor, J. R. Petta, C. M. Marcus

Coherent two-level systems, or qubits, based on electron spins in GaAs quantum dots are strongly coupled to the nuclear spins of the host lattice via the hyperfine interaction. Realizing nuclear spin control would likely improve electron spin coherence and potentially enable the nuclear environment to be harnessed for the long-term storage of quantum informa

M. Tajmar

An extension to the model from Berger is proposed to analyse the nonlinearity of the magnetic field from a rotating superconducting shell, taking into account the effect of the London penetration depth.

M. Tajmar

A fully consistent model to study electrodynamics for superconductors in the stationary and non-stationary regime has been developed based on Proca equations and a massive photon. In particular, this approach has been applied to study the electric field penetration depth in superconductors. The model shows a deviation from the charge contribution to an inter

Stéphane Sacuto, Alain Jorissen, Pierre Cruzalèbes, Olivier Chesneau

We study the close circumstellar environment of the nearby S-type star Pi^1 Gruis using high spatial-resolution, mid-infrared observations from the ESO/VLTI. Spectra and visibilities were obtained with the MIDI interferometer on the VLT Auxiliary Telescopes. The cool M5III giant Beta Gruis was used as bright primary calibrator, and a dedicated spectro-interf

Michel Gross, Michael Atlan

We propose a variant of the heterodyne holography scheme that combines the properties of off-axis and phase-shifting holography. This scheme makes it possible to filter off numerically the zero-order image alias and the technical noise of the reference. It is then possible to record and reconstruct holographic images at an extremely low signal level. We show

C. J. Davis, P. Scholz, P. Lucas, M. D. Smith

We discuss wide-field near-IR imaging of the NGC1333, L1448, L1455 and B1 star forming regions in Perseus. The observations have been extracted from a much larger narrow-band imaging survey of the Taurus-Auriga-Perseus complex. These H2 2.12 micron observations are complemented by broad-band K imaging, mid-IR imaging and photometry from the Spitzer Space Tel

Karen Yagdjian, Anahit Galstian

In this article we construct the fundamental solutions for the Klein-Gordon equation in de Sitter spacetime. We use these fundamental solutions to represent solutions of the Cauchy problem and to prove $L^p-L^q$ estimates for the solutions of the equation with and without a source term.

Mariano Chernicoff, Alberto Guijosa

We explore various aspects of the motion of heavy quarks in strongly-coupled gauge theories, employing the AdS/CFT correspondence. Building on earlier work by Mikhailov, we study the dispersion relation and energy loss of an accelerating finite-mass quark in N=4 super-Yang-Mills, both in vacuum and in the presence of a thermal plasma. In the former case, we

J. M. Leisenring, F. Kemper, G. C. Sloan

We present \emph{Spitzer} IRS data on 19 asymptotic giant branch (AGB) stars in the Large Magellanic Cloud, complementing existing published data sets of carbon stars in both Magellanic Clouds and the Milky Way, to investigate the effects of metallicity on dust and molecular spectral features arising from the circumstellar envelope. We find that the C$_2$H$_

Anthony Várilly-Alvarado, David Zywina

We construct explicit examples of E_8 lattices occurring in arithmetic for which the natural Galois action is equal to the full group of automorphisms of the lattice, i.e., the Weyl group of E_8. In particular, we give explicit elliptic curves over Q(t) whose Mordell-Weil lattices are isomorphic to E_8 and have maximal Galois action. Our main objects of stud

Venky Krishnan, Plamen Stefanov

Let $(M,g)$ be a simple Riemannian manifold with boundary and consider the geodesic ray transform of symmetric 2-tensor fields. Let the integral of $f$ along maximal geodesics vanish on an appropriate open subset of the space of geodesics in $M$. Under the assumption that the metric $g$ is real-analytic, it is shown that there exists a vector field $v$ satis

Marc Mezard, Thierry Mora

A new field of research is rapidly expanding at the crossroad between statistical physics, information theory and combinatorial optimization. In particular, the use of cutting edge statistical physics concepts and methods allow one to solve very large constraint satisfaction problems like random satisfiability, coloring, or error correction. Several aspects

Ameur Dhahri

We study a XY model which consists of a spin chain coupled to heat baths. We give a repeated quantum interaction Hamiltonian describing this model. We compute the explicit form of the associated Lindblad generator in the case of the spin chain coupled to one, two and several heat baths. We further study the properties of quantum master equation such as appro

Thibaut Jonckheere, Ken-Ichiro Imura, Thierry Martin

We study electronic transport through a magnetic molecule with an intrinsic spin $S$ coupled to two magnetic electrodes, in the incoherent regime. The molecule is modeled as a single resonant level with large Coulomb repulsion (no double occupancy). The molecular spin is isotropic and it interacts with the electronic spin through an exchange interaction. Usi

Valery A. Gaiko

In this paper, a quadratic system with two parallel straight line-isoclines is considered. This system corresponds to the system of class II in the classification of Ye Yanqian. Using the field rotation parameters of the constructed canonical system and geometric properties of the spirals filling the interior and exterior domains of its limit cycles, we prov

Gavin W. Morley, Louis-Claude Brunel, Johan van Tol

We describe a pulsed multi-frequency electron paramagnetic resonance spectrometer operating at several frequencies in the range of 110-336 GHz. The microwave source at all frequencies consists of a multiplier chain starting from a solid state synthesizer in the 12-15 GHz range. A fast PIN-switch at the base frequency creates the pulses. At all frequencies a

Michael Courtney, Amy Courtney

This paper presents a summary of seven distinct chains of evidence, which, taken together, provide compelling support for the theory that a ballistic pressure wave radiating outward from the penetrating projectile can contribute to wounding and incapacitating effects of handgun bullets. These chains of evidence include the fluid percussion model of traumatic

A. Kanigel, U. Chatterjee, M. Randeria, M. R. Norman

In the underdoped high temperature superconductors, instead of a complete Fermi surface above Tc, only disconnected Fermi arcs appear, separated by regions that still exhibit an energy gap. We show that in this pseudogap phase, the energy-momentum relation of electronic excitations near E_F behaves like the dispersion of a normal metal on the Fermi arcs, but

Michael Courtney, Amy Courtney

This paper reviews the scientific support for a ballistic pressure wave radiating outward from a penetrating projectile and causing injury and incapacitation. This phenomenon is known colloquially as &#34;hydrostatic shock.&#34; The idea apparently originates with Col. Frank Chamberlin, a World War II trauma surgeon and wound ballistics researcher. The paper

Tigran S. Varzhapetyan, Hebin Li, Gombojav O. Ariunbold, Vladimir A. Sautenkov

We have studied the intensity correlations between two orthogonally linearly polarized components of a laser field propagating through a resonant atomic medium. These experiments have been performed in a Rubidium atomic vapor. We observe that the correlations between the orthogonally polarized components of the laser beam are maximal in the absence of a magn

Simone Selenu

Variations of polarization of the electronic field is a dielectric property quantified by Resta et al. and discovered to be a Berry phase of the electronic subsystem. In order to continue the previous research we wrote a scalar phase Φas the circulation of the polarization field or in alternative and in a more general form as the flux of a new vector field c

H. S. Köhler

This report concerns the energy of neutron-matter for densities below $0.15 fm^{-3}$ and temperatures at and below $10 MeV$. Separable NN-interactions are obtained by inverse scattering from the experimental phase-shifts with specified momentum cut-offs $Λ$. Results of Brueckner-Bloch-DeDomicis as well as finite temperature Green&#39;s function calculations

E. Benckiser, R. Rückamp, T. Möller, T. Taetz

We study orbital excitations in the optical absorption spectra of YVO3 and HoVO3. We focus on an orbital absorption band observed at 0.4 eV for polarization E parallel c. This feature is only observed in the intermediate, monoclinic phase. By comparison with the local crystal-field excitations in VOCl and with recent theoretical predictions for the crystal-f

Dana I. Casetti-Dinescu, Jeffrey L. Carlin, Terrence M. Girard, Steven R. Majewski

We present a 3D kinematical analysis of stars located in Kapteyn Selected Area 71 (l = 167.1, b = -34.7), where previously a stellar excess was found (Dinescu et al. 2002, Newberg et al. 2002). Previous findings indicated that the stellar excess has a cold kinematical signature as inferred from proper motions, and was initially associated with debris from th

Fabio Siringo, Luca Marotta

The Gaussian Effective Potential (GEP) is derived for the non-Abelian SU(2)xU(1) gauge theory of electroweak interactions. First the problem of gauge invariance is addressed in the Abelian U(1) theory, where an optimized GEP is shown to be gauge invariant. The method is then extended to the full non-Abelian gauge theory where, at variance with naive derivati

Joerg R. Hoerandel

Recent measurements of the properties of cosmic rays above 10^17 eV are summarized and implications on our contemporary understanding of their origin are discussed. Cosmic rays with energies exceeding 10^20 eV have been measured, they are the highest-energy particles in the Universe. Particles at highest energies are expected to be only marginally deflected

L. H. Haddad, L. D. Carr

We show that Bose-Einstein condensates in a honeycomb optical lattice are described by a nonlinear Dirac equation in the long wavelength, mean field limit. Unlike nonlinear Dirac equations posited by particle theorists, which are designed to preserve the principle of relativity, i.e., Poincaré covariance, the nonlinear Dirac equation for Bose-Einstein conden

A. Beetz, C. Gollwitzer, R. Richter, I. Rehberg

We observe the dynamics of waves propagating on the surface of a ferrofluid under the influence of a spatially and temporarily modulated field. In particular, we excite plane waves by a travelling lamellar modulation of the magnetization. By this external driving both the wavelength and the propagation velocity of the waves can be controlled. The amplitude o

Axel de Goursac, Jean-Christophe Wallet, Raimar Wulkenhaar

Candidates for renormalisable gauge theory models on Moyal spaces constructed recently have non trivial vacua. We show that these models support vacuum states that are invariant under both global rotations and symplectic isomorphisms which form a global symmetry group for the action. We compute the explicit expression in the position space for these vacuum c

G. Ramalho, M. T. Pena, Franz Gross

The covariant spectator formalism is used to model the nucleon and the $Δ$(1232) as a system of three constituent quarks with their own electromagnetic structure. The definition of the ``fixed-axis&#39;&#39; polarization states for the diquark emitted from the initial state vertex and absorbed into the final state vertex is discussed. The helicity sum over t

S. T. Fletcher, W. J. Chaplin, Y. Elsworth, R. New

We introduce a modified version of a standard power spectrum `peak-bagging&#39; technique which is designed to gain some of the advantages that fitting the entire low-degree p-mode power spectrum simultaneously would bring, but without the problems involved in fitting a model incorporating many hundreds of parameters. Employing Monte-Carlo simulations we sho

P. Blake, P. D. Brimicombe, R. R. Nair, T. J. Booth

Graphene is only one atom thick, optically transparent, chemically inert and an excellent conductor. These properties seem to make this material an excellent candidate for applications in various photonic devices that require conducting but transparent thin films. In this letter we demonstrate liquid crystal devices with electrodes made of graphene which sho

Adrien Poteaux, Marc Rybowicz

We have designed a new symbolic-numeric strategy to compute efficiently and accurately floating point Puiseux series defined by a bivariate polynomial over an algebraic number field. In essence, computations modulo a well chosen prime $p$ are used to obtain the exact information required to guide floating point computations. In this paper, we detail the symb

Deepa Kasinathan, K. Koepernik, W. E. Pickett

The zero temperature Mott transition region in antiferromagnetic, spin S=5/2 MnO is probed using the correlated band theory LSDA+U method. The first transition encountered is an insulator-insulator volume collapse within the rocksalt structure that is characterized by an unexpected Hund&#39;s rule violating `spin-flip&#39; moment collapse. This spin-flip to

A. E. Sansom, M. S. Northeast

Stellar population characteristics are presented for a sample of low luminosity early-type galaxies (LLEs) in order to compare them with their more luminous counterparts. Long-slit spectra of a sample of 10 LLEs were taken with the ESO New Technology Telescope, selected for their low luminosities. Line strengths were measured on the Lick standard system. Lic

Mikito Koshino, Tsuneya Ando

The magneto-optical absorption properties of graphene multilayers are theoretically studied. It is shown that the spectrum can be decomposed into sub-components effectively identical to the monolayer or bilayer graphene, allowing us to understand the spectrum systematically as a function of the layer number. Odd-layered graphenes always exhibit absorption pe

S. Beheshti, K. J. H. Law, P. G. Kevrekidis, Mason A. Porter

Motivated by recent experiments in optics and atomic physics, we derive an averaged nonlinear partial differential equation describing the dynamics of the complex field in a nonlinear Schroedinger model in the presence of a periodic nonlinearity and a periodically-varying dissipation coefficient. The incorporation of dissipation is motivated by experimental

Huey-Wen Lin, Saul D. Cohen, Robert G. Edwards, David G. Richards

Experiments at Jefferson Laboratory, MIT-Bates, LEGS, Mainz, Bonn, GRAAL, and Spring-8 offer new opportunities to understand in detail how nucleon resonance ($N^*$) properties emerge from the nonperturbative aspects of QCD. Preliminary data from CLAS collaboration, which cover a large range of photon virtuality $Q^2$ show interesting behavior with respect to

K. R. Ito, E. Seiler

We discuss in some detail certain gaps and open problems in the recent paper by E. T. Tomboulis, which claims to give a rigorous proof of quark confinement in 4D lattice Yang-Mills theory for all values of the bare coupling. We also discuss what would be needed to fill the gaps in his proof.

Aurore Delaigle, Peter Hall, Hans-Georg Müller

We consider nonparametric estimation of a regression function for a situation where precisely measured predictors are used to estimate the regression curve for coarsened, that is, less precise or contaminated predictors. Specifically, while one has available a sample $(W_1,Y_1),...,(W_n,Y_n)$ of independent and identically distributed data, representing obse

Francesca Matteucci

I will review the role of massive stars in galactic evolution both from the nucleosynthesis and energetics point of view. In particular, I will highlight some important observational facts explained by means of massive stars in galaxies of different morphological type: the Milky Way, ellipticals and dwarf spheroidals. I will describe first the time-delay mod

M. Castro, S. Vauclair, O. Richard, N. C. Santos

Exoplanet-host stars (EHS) are known to present surface chemical abundances different from those of stars without any detected planet (NEHS). EHS are, on the average, overmetallic compared to the Sun. The observations also show that, for cool stars, lithium is more depleted in EHS than in NEHS. The overmetallicity of EHS may be studied in the framework of tw

S. P. Baranov

A new mechanism of the production of hypothetical $Θ(ud\bar{s}ud)^+$ pentaquark state is suggested. The considered mechanism is based on the exchange by exotic Regge trajectories in the $t$ channel. It is shown that the momentum distributions of $Θ^+$ baryons can differ significantly from the ones of the ordinary hyperons.

Xuelei Wang, Huiling Jin, Yanju Zhang, Yanhui Xi

With high luminosity and energy at the ILC and clean SM backgrounds, the top-charm production at the ILC should have powerful potential to probe new physics. The littlest Higgs model with discrete symmetry named &#34;T-parity&#34;(LHT) is one of the most promising new physics models. In this paper, we study the FC processes $e^+e^-(γγ)\to t\bar{c}$ at the IL

M. Amram, R. Shwartz, M. Teicher

Let $C(T)$ be a generalized Coxeter group, which has a natural map onto one of the classical Coxeter groups, either $B_n$ or $D_n$. Let $C_Y(T)$ be a natural quotient of $C(T)$, and if $C(T)$ is simply-laced (which means all the relations between the generators has order 2 or 3), $C_Y(T)$ is a generalized Coxeter group, too . Let $A_{t,n}$ be a group which c

Florian Libisch, Jürgen Möller, Stefan Rotter, Maxim G. Vavilov

We investigate the distribution of the lowest-lying energy states in a disordered Andreev billiard by solving the Bogoliubov-de Gennes equation numerically. Contrary to conventional predictions we find a decrease rather than an increase of the excitation gap relative to its clean ballistic limit. We relate this finding to the eigenvalue spectrum of the Wigne

Peter Hall, Yanyuan Ma

A low-degree polynomial model for a response curve is used commonly in practice. It generally incorporates a linear or quadratic function of the covariate. In this paper we suggest methods for testing the goodness of fit of a general polynomial model when there are errors in the covariates. There, the true covariates are not directly observed, and convention

F. B. Anders

We present a method for the calculation of dynamical correlation functions of quantum impurity systems out of equilibrium using Wilson&#39;s numerical renormalization group. Our formulation is based on a complete basis set of the Wilson chain and embeds the recently derived algorithm for equilibrium spectral functions. Our method fulfills the spectral weight

N. Fountoulakis, D. Kühn, D. Osthus

We show that there is a constant c>0 so that for any fixed r which is at least 3 a.a.s. an r-regular graph on n vertices contains a complete graph on c n^{1/2} vertices as a minor. This confirms a conjecture of Markstrom. Since any minor of an r-regular graph on n vertices has at most rn/2 edges, our bound is clearly best possible up to the value of the cons

B. O&#39;Halloran, S. C. Madden, N. P. Abel

Archival Spitzer observations of 41 starburst galaxies that span a wide range in metallicity reveal for the first time a correlation between the [FeII]/[NeII] 26.0/12.8 micron ratio and the electron gas density as traced by the 18.7/33.4 micron [SIII] ratio, with the [FeII]/[NeII] ratio decreasing with increasing gas density. The correlations of the [FeII]/[

Joel L. Horowitz, Enno Mammen

This paper discusses a nonparametric regression model that naturally generalizes neural network models. The model is based on a finite number of one-dimensional transformations and can be estimated with a one-dimensional rate of convergence. The model contains the generalized additive model with unknown link function as a special case. For this case, it is s

P. R. Eastham

A trapped polariton condensate with continuous pumping and decay is analyzed using a generalized Gross-Pitaevskii model. Whereas an equilibrium condensate is characterized by a macroscopic occupation of a ground state, here the steady-states take more general forms. Some are characterized by a large population in an excited state, and others by large populat