May 2006 arXiv papers — page 11

D. Janjusevic, M. S. Grbic, M. Pozek, A. Dulcic

The microwave response of high quality niobium films in a perpendicular static magnetic field has been investigated. The complex frequency shift was measured up to the upper critical fields. The data have been analyzed by the effective conductivity model for the type-II superconductors in the mixed state. This model is found to yield consistent results for t

Alexie M. Kolpak, Na Sai, Andrew M. Rappe

We examine the application of short-circuit electrical boundary conditions in density functional theory calculations of ferroelectric thin films. Modeling PbTiO$_3$ films with Pt electrodes, we demonstrate that under periodic boundary conditions of supercells, short-circuit conditions for the electrodes are equivalently satisfied in two repeated slab geometr

E. Majernikova, S. Shpyrko

We study statistical properties of excited levels of the E x (b_1+b_2) Jahn-Teller model. The multitude of avoided crossings of energy levels is generally claimed to be a testimony of quantum chaos. We found that apart from two limiting cases (E x e and Holstein model) the distribution of nearest-neighbor spacings is rather stable as to the change of paramet

T. Thonhauser, K. M. Rabe

We present first-principles density-functional calculations using the local density approximation to investigate the structural instability of cubic perovskite BaBiO_3. This material might exhibit charge disproportionation and some evidence thereof has been linked to the appearance of an additional, fourth peak in the experimental IR spectrum. However, our r

Peter Morgan

The assumptions required for the derivation of Bell inequalities are not usually satisfied for random fields in which there are any thermal or quantum fluctuations, in contrast to the general satisfaction of the assumptions for classical two point particle models. Classical random field models that explicitly include the effects of quantum fluctuations on me

Fabio Bresolin, Grzegorz Pietrzynski, Miguel A. Urbaneja, Wolfgang Gieren

As part of the Araucaria Project, we present the first spectral catalog of supergiant stars in the Local Group dwarf irregular galaxy WLM. In assigning a spectral classification to these stars we accounted for the low metal content of WLM relative to the galactic standards used in the MK process, by using classification criteria developed for B and A supergi

M. C. Cushing, T. L. Roellig, M. S. Marley, D. Saumon

We present a low-resolution (R = 90), 5.5-38 micron spectral sequence of a sample of M, L, and T dwarfs obtained with the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope. The spectra exhibit prominent absorption bands of H_2O at 6.27 microns, CH_4 at 7.65 microns, and NH_3 at 10.5 microns and are relatively featureless at lambda > 15 microns.

W. M. Wood-Vasey, J. L. Sokoloski

We propose that a nova shell ejected from a recurrent nova progenitor system created the evacuated region around the explosion center of SN 2002ic. In this picture, periodic shell ejections due to nova explosions on a white dwarf sweep up the slow wind from the binary companion, creating density variations and instabilities that lead to structure in the circ

K. J. Pearson, R. I. Hynes, D. Steeghs, P. G. Jonker

We present optical and ultraviolet spectra, lightcurves, and Doppler tomograms of the low-mass X-ray binary EXO 0748-676. Using an extensive set of 15 emission line tomograms, we show that, along with the usual emission from the stream and ``hot spot'', there is extended non-axisymmetric emission from the disk rim. Some of the emission and Halpha and

Emmanuel Rollinde, Elisabeth Vangioni, Keith A. Olive

We calculate the evolution of Li6 generated from cosmic rays produced by an early population of massive stars. The computation is performed in the framework of hierarchical structure formation and is based on cosmic star formation histories constrained to reproduce the observed star formation rate at redshift z \la 6, the observed chemical abundances in damp

Syksy Rasanen

We discuss the Buchert equations, which describe the average expansion of an inhomogeneous dust universe. In the limit of small perturbations, they reduce to the Friedmann-Robertson-Walker equations. However, when the universe is very inhomogeneous, the behaviour can be qualitatively different from the FRW case. In particular, the average expansion rate can

Thomas Lilly, Uta Fritze-v. Alvensleben

We have extended our evolutionary synthesis code, GALEV, to include Lick/IDS absorption-line indices for both simple and composite stellar population models (star clusters and galaxies), using the polynomial fitting functions of Worthey et al. (1994) and Worthey & Ottaviani (1997). We present a mathematically advanced Lick Index Analysis Tool (LINO) for the

Omaira Gonzalez-Martin, Josefa Masegosa, Isabel Marquez, Martin A. Guerrero

We report the results from an homogeneous analysis of the X-ray (Chandra-ACIS) data available for a sample of 51 LINER galaxies selected from the catalogue by Carrillo et al. (1999) and representative of the population of bright LINER sources. The nuclear X-ray morphology has been classified attending to their nuclear compactness in the hard band (4.5-8.0 ke

Sergey Ustyugov

Three-dimensional magnetohydrodynamical large eddy simulations of solar surface convection using realistic model physics is conducted. The effects of magnetic fields on thermal structure of convective motions into radiative layers, the range of convection cell sizes and penetration depths of convection is investigated. We simulate a some portion of the solar

Orsola De Marco

Only a handful of binary central stars of planetary nebulae (PNe) are known today, due to the difficulty of detecting their companions. Preliminary results from radial velocity surveys, however, seem to indicate that binarity plays a fundamental,rather than marginal role in the evolution of PNe and that the close binary fraction might be much larger than the

A. H. Cerqueira, J. Canto, A. C. Raga, M. J. Vasconcelos

Neutral clumps immersed in HII regions are frequently found in star formation regions. We investigate here the formation of tail of neutral gas, which are not reached by the direct ionizing flux coming from two massive stars, using both an analytical approximation, that allows us to estimate the shadow geometry behind the clumps for different initial geometr

S. Garcia-Burillo, A. Fuente, J. Martin-Pintado, A. Usero

Observational constraints provided by high resolution and high sensitivity observations of external galaxies made in the millimeter and submillimeter range have started to put on a firm ground the study of extragalactic chemistry of molecular gas. In particular, the availability of multi-species and multi-line surveys of nearby galaxies is central to the int

M. Collobert, M. Sarzi, R. L. Davies, H. Kuntschner

We have investigated the properties of a volume and magnitude limited sample of nearby early type galaxies that were carefully selected from the AAO two degree field galaxy redshift survey. We used images from the DSS to confirm the E/S0 morphologies, and augmented this sample with field galaxies from Colbert et al. 2001. We present spectroscopic observation

Josefina Montalban, Francesca D'Antona

The Teff location of Pre-Main Sequence (PMS) evolutionary tracks depends on the treatment of over-adiabaticity. We present here the PMS evolutionary tracks computed by using the mixing length theory of convection (MLT) in which the alpha_MLT=l/H_p parameter calibration is based on 2D--hydrodynamical models (Ludwig et al. 1999). These MLT--α^2D stellar models

F. Coppolani, P. Petitjean, F. Stoehr, E. Rollinde

We present the transverse flux correlation function of the Lyman-alpha forest in quasar absorption spectra at z~2.1 from VLT-FORS and VLT-UVES observations of a total of 32 pairs of quasars; 26 pairs with separations in the range 0.6<theta<4 arcmin and 6 pairs with 4<theta<10 arcmin. Correlation is detected at the 3sigma level up to separations of the order

Jonathan Irwin, Suzanne Aigrain, Simon Hodgkin, Mike Irwin

We report on the results of a V and i-band time-series photometric survey of M34 (NGC 1039) using the Wide Field Camera (WFC) on the Isaac Newton Telescope (INT), achieving better than 1% precision per data point for 13 <~ i <~ 17. Candidate cluster members were selected from a V vs V-I colour-magnitude diagram over 14 < V < 24 (0.12 <~ M/Msun <~ 1.0), findi

R. D. Jeffries, P. F. L. Maxted, J. M. Oliveira, Tim Naylor

We have used precise radial velocity measurements for a large number of candidate low-mass stars and brown dwarfs, to show that the young Sigma Ori ``cluster&#39;&#39; consists of two spatially superimposed components which are kinematically separated by 7 km/s in radial velocity, and which have different mean ages. We examine the relationship of these two k

T. V. Mishenina, O. Bienaym&#39;e, T. I. Gorbaneva, C. Charbonnel

The aim of this paper is to provide the fundamental parameters and abundances for a large sample of local clump giants with a high accuracy. The selection of clump stars for the sample group was made applying a color - absolute magnitude window to nearby Hipparcos stars. The abundances of carbon and nitrogen were obtained from molecular synthetic spectrum, t

Jiren Liu, Hongguang Bi, Long-Long Feng, Li-Zhi Fang

We study the Gunn-Peterson effect of the photo-ionized intergalactic medium(IGM) in the redshift range 5< z <6.4 using semi-analytic simulations based on the lognormal model. Assuming a rapidly evolved and spatially uniform ionizing background, the simulation can produce all the observed abnormal statistical features near redshift z ~ 6. They include: 1) rap

O. I. Wong, G. R. Meurer, K. Bekki, D. J. Hanish

We have found the peculiar galaxy NGC922 to be a new drop-through ring galaxy using multi-wavelength (UV-radio) imaging and spectroscopic observations. Its `C&#39;-shaped morphology and tidal plume indicate a recent strong interaction with its companion which was identified with these observations. Using numerical simulations we demonstrate that the main pro

L. M. Stanford, G. S. Da Costa, J. E. Norris, R. D. Cannon

We present a metallicity distribution based on photometry and spectra for 442 omega Cen cluster members that lie at the main sequence turnoff region of the color-magnitude diagram. This distribution is similar to that found for the red giant branch. The distribution shows a sharp rise to a mean of [Fe/H] = -1.7 with a long tail to higher metallicities. Ages

Zhongmu Li, Fenghui Zhang, Zhanwen Han

We determine relative stellar ages and metallicities mainly for about 80 elliptical galaxies in low and high density environments via the latest binary stellar population (BSP) synthesis model and test a latest hierarchical formation model of elliptical galaxies which adopted the new $Λ$CDM cosmology for the first time. The stellar ages and metallicities of

Patricio Rojo, Joseph Harrington

We have developed a new method that uses wavelet analysis to remove interference fringe patterns from images. This method is particularly useful for flat fields in the common case where fringes vary between the calibration and object data. We analyze the efficacy of this method by creating fake flats with fictitious fringes and removing the fringes. We find

A. Bonacic Marinovic, R. G. Izzard, M. Lugaro, O. R. Pols

We study s-process element abundance ratios in stars by carrying out stellar population synthesis, using a rapid synthetic stellar evolution code which includes an up-to-date treatment of AGB nucleosynthesis and evolution. In contrast to other studies, we find that a large spread in the 13C efficiency parameter (13C_eff) is not needed to explain the observed

Thomas Buchert

This paper focusses on the barely understood gap between the weakly nonlinear regime of structure formation and the onset of the virialized regime. While the former is accessed through perturbative calculations and the latter through virialization conditions incorporating dynamical stresses that arise in collisionless self-gravitating systems due to velocity

Jian-Ming Tang, Jeremy Levy, Michael E. Flatte

We propose a method for all-electrical initialization, control and readout of the spin of single ions substituted into a semiconductor. Mn ions in GaAs form a natural example. In the ion&#39;s ground state the Mn core spin magnetic moment locks antiparallel to the spin and orbital magnetic moment of a bound valence hole from the GaAs host. Direct electrical

Abhijit Champanerkar, Ilya Kofman

We show that if {L_n} is any infinite sequence of links with twist number tau(L_n) and with cyclotomic Jones polynomials of increasing span, then lim sup tau(L_n)=infty. This implies that any infinite sequence of prime alternating links with cyclotomic Jones polynomials must have unbounded hyperbolic volume. The main tool is the multivariable twist--bracket

H. Haberzettl, K. Nakayama, S. Krewald

A fully gauge-invariant (pseudoscalar) meson photoproduction amplitude off a nucleon including the final-state interaction is derived. The approach based on a comprehensive field-theoretical formalism developed earlier by one of the authors replaces certain dynamical features of the full interaction current by phenomenological auxiliary contact currents. A p

Hrayr H. Matevosyan, Anthony W. Thomas, Peter C. Tandy

We include a generalized infinite class of quark-gluon vertex dressing diagrams in a study of how dynamics beyond the ladder-rainbow truncation influences the Bethe-Salpeter description of light quark pseudoscalar and vector mesons. The diagrammatic specification of the vertex is mapped into a corresponding specification of the Bethe-Salpeter kernel, which p

F. T. Brandt, J. Frenkel, C. M. Muramoto

We compute higher order contributions to the free energy of noncommutative quantum electrodynamics at a nonzero temperature $T$. Our calculation includes up to three-loop contributions (fourth order in the coupling constant $e$). In the high temperature limit we sum all the {\it ring diagrams} and obtain a result which has a peculiar dependence on the coupli

Chris Waltham, Andrzej Kotlicki

The full characterization of a stringed musical instrument requires measuring the motion of the strings in at least two dimensions. Traditionally this has been done using electromagnetic means or by optical transmission. However in many instruments the strings are not made of steel, nor are the strings easily accessible on both sides. In this work it is show

Oscar Cata

We reassess a work done by Migdal on the spectrum of low-energy vector mesons in QCD in the light of the AdS-QCD correspondence. Recently, a tantalizing parallelism was suggested between Migdal&#39;s work and a family of holographic duals of QCD. Despite the intriguing similarities, both approaches face a major drawback: the spectrum is in conflict with well

Hao Wu

We use the spanning tree model for Khovanov homology to study Legendrian links. This leads to an alternative proof for Ng&#39;s Khovanov bound for the Thurston-Bennequin number and to both a necessary and a sufficient condition for this bound to be sharp.

Guthrie B. Partridge, Wenhui Li, Ramsey I. Kamar, Yean-An Liao

Zwierlein and Ketterle rely on subjective arguments and fail to recognize important differences in physical parameters between our experiment and theirs. We stand by the conclusions of our original report.

Lei Chang, Yu-Xin Liu, Mandar S. Bhagwat, Craig D. Roberts

On a bounded, measurable domain of non-negative current-quark mass, realistic models of QCD&#39;s gap equation can simultaneously admit two inequivalent dynamical chiral symmetry breaking (DCSB) solutions and a solution that is unambiguously connected with the realisation of chiral symmetry in the Wigner mode. The Wigner solution and one of the DCSB solution

B. Charneski, A. F. Ferrari, M. Gomes

This work is dedicated to the study of the noncommutative Gross-Neveu model. As it is known, in the canonical Weyl-Moyal approach the model is inconsistent, basically due to the separation of the amplitudes into planar and nonplanar parts. We prove that if instead a coherent basis representation is used, the model becomes renormalizable and free of the afore

Etera R. Livine, Simone Speziale, Joshua L. Willis

We consider the recent calculation gr-qc/0508124 of the graviton propagator in the spinfoam formalism. Within the 3d toy model introduced in gr-qc/0512102, we test how the spinfoam formalism can be used to construct the perturbative expansion of graviton amplitudes. Although the 3d graviton is a pure gauge, one can choose to work in a gauge where it is not z

Michael B. Baer

An alphabetic binary tree formulation applies to problems in which an outcome needs to be determined via alphabetically ordered search prior to the termination of some window of opportunity. Rather than finding a decision tree minimizing $\sum_{i=1}^n w(i) l(i)$, this variant involves minimizing $\log_a \sum_{i=1}^n w(i) a^{l(i)}$ for a given $a \in (0,1)$.

Daniel Burgarth, Vittorio Giovannetti

We give a simple and physically intuitive necessary and sufficient condition for a map acting on a compact metric space to be mixing (i.e. infinitely many applications of the map transfer any input into a fixed convergency point). This is a generalization of the &#34;Lyapunov direct method&#34;. First we prove this theorem in topological spaces and for arbit

Ari Brynjolfsson

In 2001 Lori M. Lubin and Allan Sandage, using big-bang cosmology for interpreting the data, found the surface brightness of galaxies to be inversely proportional to about the third power of (1+z), while the contemporary big-bang cosmology predicts that the surface brightness is inversely proportional to the fourth power of (1+z). In contrast, these surface

J. Gegenberg, V. Suneeta

We examine the fixed points to first-order RG flow of a non-linear sigma model with background metric, dilaton and tachyon fields. We show that on compact target spaces, the existence of fixed points with non-zero tachyon is linked to the sign of the second derivative of the tachyon potential $V&#39;&#39;(T)$ (this is the analogue of a result of Bourguignon

Kazunori Kohri, Fumihiro Takayama

We consider Big Bang Nucleosynthesis (BBN) with long lived charged massive particles. Before decaying, the long lived charged particle recombines with a light element to form a bound state like a hydrogen atom. This effect modifies the nuclear reaction rates during the BBN epoch through the modifications of the Coulomb field and the kinematics of the capture

Marco D&#39;Anna, Marco Fontana

We introduce a new general construction, denoted by $R\JoinE$, called the amalgamated duplication of a ring $R$ along an $R$--module $E$, that we assume to be an ideal in some overring of $R$. (Note that, when $E^2 =0$, $R\JoinE$ coincides with the Nagata&#39;s idealization $R\ltimes E$.) After discussing the main properties of the amalgamated duplication $R

Guangyong Xu, P. M. Gehring, G. Shirane

We have performed a series of neutron diffuse scattering measurements on a single crystal of the solid solution Pb(Zn$_{1/3}$Nb$_{2/3}$)O$_3$ (PZN) doped with 8% PbTiO$_3$ (PT), a relaxor compound with a Curie temperature T$_C \sim 450$ K, in an effort to study the change in local polar orders from the polar nanoregions (PNR) when the material enters the fer

A. V. Afanasev, O. K. Baker, K. W. McFarlane, G. H. Biallas

The PVLAS collaboration has observed rotation of the plane of polarization of light passing through a magnetic field in vacuum and has proposed that the effect is due to interaction of photons with very light spin-zero bosons. This would represent new physics beyond the Standard Model, and hence it is of high interest to test this hypothesis. We describe a p

A. L. Gadelha, Dafni Z. Marchioro, Daniel L. Nedel

In this letter new aspects of string theory propagating in a pp-wave time dependent background with a null singularity are explored. It is shown the appearance of a 2d entanglement entropy dynamically generated by the background. For asymptotically flat observers, the vacuum close to the singularity is unitarily inequivalent to the vacuum at $τ= -\infty$ and

Jens Köplinger

In reference to S. W. Hawking's article "Information Loss in Black Holes" [S. W. Hawking, Phys. Rev. D 72 (2005) 084013], where a four dimensional Euclidean spacetime without Wick rotation is adopted for quantum gravity, an arithmetic with multiplicative modulus is mentioned here which incorporates both a hyperbolic (Minkowski) and circular (Euclidean) metri

Roman Bezrukavnikov, Michael Finkelberg, Victor Ostrik

We prove a weak version of Lusztig&#39;s conjecture on explicit description of the asymptotic Hecke algebras (both finite and affine), and explain its relation to Lusztig&#39;s classification of character sheaves.

A. E. Shalyt-Margolin

In this work the Vacuum Energy Density Problem or Dark Energy Problem is studied on the basis of the earlier results by the author within the scope of the Holographic Principle. It is demonstrated that the previously introduced deformed quantum field theory at a nonuniform lattice in the finite-dimensional hypercube is consistent with the Holographic Princip

Yu-Tung Chen, Ming-Hsien Tu

We rederive dispersionless Hirota equations of the dispersionless Toda hierarchy from the method of kernel formula provided by Carroll and Kodama. We then apply the method to derive dispersionless Hirota equations of the extended dispersionless BKP(EdBKP) hierarchy proposed by Takasaki. Moreover, we verify associativity equations (WDVV equations) in the EdBK

Roman Sauer

We provide a proof for an inequality between volume and L2-Betti numbers of aspherical manifolds for which Gromov outlined a strategy based on general ideas of Connes. The implementation of that strategy involves measured equivalence relations, Gaboriau&#39;s theory of L2-Betti numbers of R-simplicial complexes, and other themes of measurable group theory. F

William Thistleton, Kenric Nelson, John A. Marsh, Constantino Tsallis

Addendum: The generalized Box-M\"uller algorithm provides a methodology for generating q-Gaussian random variates. The parameter $-\infty<q\leq3$ is related to the shape of the tail decay; $q<1$ for compact-support including parabola $(q=0)$; $1<q\leq3$ for heavy-tail including Cauchy $(q=2)$. This addendum clarifies the transformation $q'=((3q-1)/(q+1))$ wi

Elena Caceres, Alberto Guijosa

Following recent developments, we employ the AdS/CFT correspondence to determine the drag force exerted on an external quark that moves through an N=4 super-Yang-Mills plasma with a non-zero R-charge density (or, equivalently, a non-zero chemical potential). We find that the drag force is larger than in the case where the plasma is neutral, but the dependenc

Troels Harmark, Marta Orselli

We study the thermodynamics of U(N) N=4 Super Yang-Mills (SYM) on RxS^3 with non-zero chemical potentials for the SU(4) R-symmetry. We find that when we are near a point with zero temperature and critical chemical potential, N=4 SYM on RxS^3 reduces to a quantum mechanical theory. We identify three such critical regions giving rise to three different quantum

Ze-Long Yi, Tong-Jie Zhang

Using the absolute ages of passively evolving galaxies observed at different redshifts, one can obtain the differential ages, the derivative of redshift $z$ with respect to the cosmic time $t$ (i.e. ${\rm d} z/{\rm d}t$). Thus, the Hubble parameter $H(z)$ can be measured through the relation $H(z)=-({\rm d} z/{\rm d}t)/(1+z)$. By comparing the measured Hubbl

Jacek Guzik, Gary Bernstein, Robert E. Smith

We investigate three potential sources of bias in distance estimations made assuming that a very simple estimator of the baryon acoustic oscillation (BAO) scale provides a standard ruler. These are the effects of the non-linear evolution of structure, scale-dependent bias and errors in the survey window function estimation. The simple estimator used is the p

F. Bruemmer, A. Hebecker, M. Trapletti

We investigate, in the general framework of KKLT, the mediation of supersymmetry breaking by fields propagating in the strongly warped region of the compactification manifold (&#39;throat fields&#39;). Such fields can couple both to the supersymmetry breaking sector at the IR end of the throat and to the visible sector at the UV end. We model the supersymmet

Z. Pajovic, M. Bozovic, Z. Radovic, J. Cayssol

We study the Josephson effect in clean heterojunctions that consist of superconductors connected through two metallic ferromagnets with insulating interfaces. We solve the scattering problem based on the Bogoliubov--de Gennes equation for any relative orientation of in-plane magnetizations, arbitrary transparency of interfaces, and mismatch of Fermi wave vec

Jorge Mondejar, Antonio Pineda, Joan Rojo

We study QCD in 1+1 dimensions in the large $N_c$ limit using light-front Hamiltonian perturbation theory in the $1/N_c$ expansion. We use this formalism to exactly compute hadronic transition matrix elements for arbitrary currents at leading order in $1/N_c$. We compute the semileptonic differential decay rate of a heavy meson, $dΓ/dx$, and its moments, $M_

Raphael Gavazzi, Genevieve Soucail

AIMS: We present a weak lensing search of galaxy clusters in the 4 deg2 of the CFHT Legacy Survey Deep. This work aims at building a mass-selected sample of clusters. METHODS: We use the deep i&#39; band images to perform weak lensing mass reconstructions and to identify high convergence peaks. Thanks to the availability of deep ugriz exposures, sources are

Kevin H. Knuth

Histograms are convenient non-parametric density estimators, which continue to be used ubiquitously. Summary quantities estimated from histogram-based probability density models depend on the choice of the number of bins. We introduce a straightforward data-based method of determining the optimal number of bins in a uniform bin-width histogram. By assigning

George J. McNinch

Let F be an algebraically closed field and let G be a semisimple F-algebraic group for which the characteristic of F is *very good*. If X in Lie(G) = Lie(G)(F) is a nilpotent element in the Lie algebra of G, and if C is the centralizer in G of X, we show that (i) the root datum of a Levi factor of C, and (ii) the component group C/C^o both depend only on the

I. Krichever

We prove Welter&#39;s trisecant conjecture: an indecomposable principally polarized abelian variety $X$ is the Jacobian of a curve if and only if there exists a trisecant of its Kummer variety $K(X)$.

Anita Dabrowska

The main aim of the paper is to present the analytical solution of the Belavkin quantum filtering equation for damped harmonic oscillator being initially in the squeezed coherent state for diffusion observation with complex white noise. The comparison of the a priori and a posteriori mean value of the optical quadrature operators and the photon number operat

Subhash Kak

We show how the anisotropy resulting from the motion of an observer in an isotropic universe may be determined by measurements. This provides a means to identify inertial frames, yielding a simple resolution to the twins paradox of relativity theory. We propose that isotropy is a requirement for a frame to be inertial; this makes it possible to relate motion

Shigeki Onoda, Naoyuki Sugimoto, Naoto Nagaosa

A unified theory of the anomalous Hall effect (AHE) is presented for multi-band ferromagnetic metallic systems with dilute impurities. In the clean limit, the AHE is mostly due to the extrinsic skew-scattering. When the Fermi level is located around anti-crossing of band dispersions split by spin-orbit interaction, the intrinsic AHE to be calculated ab initi

I. V. Bondarev, B. Vlahovic

The entanglement of two atoms (ions) doped into a carbon nanotube has been investigated theoretically. Based on the photon Green function formalism for quantizing electromagnetic field in the presence of carbon nanotubes, small-diameter metallic nanotubes are shown to result in a high degree of the two-qubit atomic entanglement for long times due to the stro

Ronald Hanson, Guido Burkard

We propose a set of universal gate operations for the singlet-triplet qubit realized by two electron spins in a double quantum dot, in the presence of a fixed inhomogeneous magnetic field. All gate operations are achieved by switching the potential offset between the two dots with an electrical bias, and do not require time-dependent control of the tunnel co

Alessandro Cafarella

In the first part of my thesis I am concerned with the phenomenology of DGLAP equations, and in particular I propose an algorithm to solve them numerically and discuss its implementation in a computer program. I also illustrate some applications of these studies, including a prediction for the total cross section for Higgs detection at the LHC and for study

K. Børkje, A. Sudbø

Tunnelling between non-centrosymmetric superconductors with significant spin-orbit splitting is studied theoretically in a two-band treatment of the problem. We find that the critical Josephson current may be modulated by changing the relative angle between the vectors describing absence of inversion symmetry on each side of the junction. The presence of two

Christof Gattringer

We represent Polyakov loops and their correlators as spectral sums of eigenvalues and eigenmodes of the lattice Dirac operator. The deconfinement transition of pure gauge theory is characterized as a change in the response of moments of eigenvalues to varying the boundary conditions of the Dirac operator. We argue that the potential between static quarks is

Federica Legger, Thomas Schietinger

Radiative decays of polarized Lambda_b baryons represent an attractive possibility to measure the helicity of the photon emitted in the b --> s gamma quark transition and thus to subject the Standard Model to a stringent test at existing and future hadron colliders. The most abundant mode, Lambda(1116) gamma, is experimentally very challenging because of the

Supriyo Bandyopadhyay

Champions of spintronics often claim that spin based signal processing devices will vastly increase speed and/or reduce power dissipation compared to traditional charge based electronic devices. Yet, not a single spintronic device exists today that can lend credence to this claim. Here, I show that no spintronic device that clones conventional electronic dev

R. F. Wagenbrunn, L. Ya. Glozman

A fast restoration of chiral symmetry in excited mesons is demonstrated. A minimal &#34;realistic&#34; chirally symmetric confining model is used, where the only interaction between quarks is the linear instantaneous Lorentz-vector confining potential. Chiral symmetry breaking is generated via the nonperturbative resummation of valence quarks self-energy loo

Francois Gelis, Raju Venugopalan

We discuss a method for computing the generating function for the multiplicity distribution in field theories with strong time dependent external sources. At leading order, the computation of the generating function reduces to finding a pair of solutions of the classical equations of motion, with non-standard temporal boundary conditions.

Cédric Bonnafé

We study some aspects of the representation theory of Mantaci-Reutenauer algebras: Cartan matrix, Loewy length, modular representations.

Sergey D. Ganichev, Vasily V. Bel&#39;kov, Sergey A. Tarasenko, Sergey N. Danilov

Spin-orbit coupling provides a versatile tool to generate and to manipulate the spin degree of freedom in low-dimensional semiconductor structures. The spin Hall effect, where an electrical current drives a transverse spin current and causes a nonequilibrium spin accumulation observed near the sample boundary, the spin-galvanic effect, where a nonequilibrium

Guy Barles

Recently, C. Imbert & R. Monneau study the homogenization of coercive Hamilton-Jacobi Equations with a $u/e$-dependence : this unusual dependence leads to a non-standard cell problem and, in order to solve it, they introduce new ideas to obtain the estimates on the oscillations of the solutions. In this article, we use their ideas to provide new homogenizati

Krisztian Kis-Szabo, Peter Szepfalusy, Gergely Szirmai

The two Bose--Einstein condensed phases of a polar spin-1 gas at nonzero magnetizations and temperatures are investigated. The Hugenholtz--Pines theorem is generalized to this system. Crossover to a quantum phase transition is also studied. Results are discussed in a mean field approximation.

Yulia Klochko, Alexey Kokotov

We prove a formula for the determinant of Laplacian on an arbitrary compact polyhedral surface of genus one. This formula generalizes the well-known Ray-Singer result for a flat torus. A special case of flat conical metrics given by the modulus of a meromorphic quadratic differential on an elliptic surface is also considered. We study the determinant of Lapl

M. Kadler, P. A. Hughes, E. Ros, M. F. Aller

In this letter we present the results of a wavelet analysis of the radio light curve of the BL Lac Object PKS B0048-097 from the University of Michigan Radio Astronomy Observatory monitoring program at 8GHz during twenty-five years, from 1979 to 2004. The results show a remarkable periodicity of 450-470 days in the early 1980s that changed to a ~585 day peri

P. Süle, M. Menyhárd

The ion-sputtering induced transient enhanced intermixing has been studied by molecular dynamics (MD) simulations in Pt/Ti and its anomalous nature has been explained as a superdiffusive transient enhanced interdiffusion. We find ballistic mixing and a robust mass effect in Pt/Ti. The sum of the square of atomic displacements ($<R^2>$) asymptotically grows n

Luca Donetti, Franco Neri, Miguel A. Munoz

We report on some recent developments in the search for optimal network topologies. First we review some basic concepts on spectral graph theory, including adjacency and Laplacian matrices, and paying special attention to the topological implications of having large spectral gaps. We also introduce related concepts as ``expanders&#39;&#39;, Ramanujan, and Ca

Philippe Brax, Jerome Martin

We consider the coupling of quintessence to observable matter in supergravity and study the dynamics of both supersymmetry breaking and quintessence in this context. We investigate how the quintessence potential is modified by supersymmetry breaking and analyse the structure of the soft supersymmetry breaking terms. We pay attention to their dependence on th

W. P. S. Meikle, S. Mattila, C. L. Gerardy, R. Kotak

We present late-time (590-994 d) mid-IR photometry of the normal, but highly-reddened Type IIP supernova SN 2002hh. Bright, cool, slowly-fading emission is detected from the direction of the supernova. Most of this flux appears not to be driven by the supernova event but instead probably originates in a cool, obscured star-formation region or molecular cloud

M. Kemmler, C. Guerlich, A. Sterck, H. Poehler

We study experimentally the critical depinning current Ic versus applied magnetic field B in Nb thin films which contain 2D arrays of circular antidots placed on the nodes of quasiperiodic (QP) fivefold Penrose lattices. Close to the transition temperature Tc we observe matching of the vortex lattice with the QP pinning array, confirming essential features i

Joke Adam

The Chern-Simons actions of the multiple fundamental string and the multiple gravitational wave are established to full order in the background fields. Gauge invariance is checked. Special attention is drawn to the non-Abelian gauge transformations of the world-volume fields.

P. Anastasopoulos, T. P. T. Dijkstra, E. Kiritsis, A. N. Schellekens

The embedding of the SM hypercharge into an orientifold gauge group is studied. Possible embeddings are classified, and a systematic construction of bottom-up configurations and top-down orientifold vacua is achieved, solving the tadpole conditions in the context of Gepner orientifolds. Some hypercharge embeddings are strongly preferred compared to others. C

TWIST Collaboration, B. Jamieson, R. Bayes, Yu. I. Davydov

The quantity P_{mu}^{pi}xi, where xi is one of the muon decay parameters and $P_μ^π$ is the degree of muon polarization in pion decay, has been measured. The value P_{mu}^{pi}xi = 1.0003 +- 0.0006 stat. +- 0.0038 syst. was obtained. This result agrees with previous measurements but is over a factor of two more precise. It also agrees with the Standard Model

W. Horiuchi, Y. Suzuki

A dripline nucleus $^{22}$C is studied in a Borromean three-body model of $^{20}$C+$n$+$n$. The valence neutrons, interacting via a realistic potential, are constrained to be orthogonal to the occupied orbits in $^{20}$C. We obtain ample results supporting that $^{22}$C is an ideal $S$-wave two-neutron halo nucleus: The ground state is bound by 390-570 keV,

P. Anastasopoulos, M. Bianchi, E. Dudas, E. Kiritsis

A detailed analysis of anomalous U(1)&#39;s and their effective couplings is performed both in field theory and string theory. It is motivated by the possible relevance of such couplings in particle physics, as well as a potential signal distinguishing string theory from other UV options. The most general anomaly related effective action is analyzed and para

Tuneyoshi Kamae, Niklas Karlsson, Tsunefumi Mizuno, Toshinori Abe

We present the yield and spectra of stable secondary particles (gamma, e^+/-, nu_e, nubar_e, nu_mu, and nubar_mu) of p-p interaction in parameterized formulae to facilitate calculations involving them in astronomical environments. The formulae are derived on the up-to-date p-p interaction model by [Kamae05] which incorporates the logarithmically rising inela

Kengo Maeda, Makoto Natsuume, Takashi Okamura

In AdS/CFT duality, it is often argued that information behind the event horizon is encoded even in boundary correlators. However, its implication is not fully understood. We study a simple model which can be analyzed explicitly. The model is a two-dimensional scalar field propagating on the s-wave sector of the BTZ black hole formed by the gravitational col

CDF Collaboration

A measurement of the inclusive bottom jet cross section is presented for events containing a $Z$ boson in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV using the Collider Detector at Fermilab. $Z$ bosons are identified in their electron and muon decay modes, and $b$ jets with $E_T>20$ GeV and $|η|<1.5$ are identified by reconstructing a secondary decay vertex

Satoko Murata, Masaaki Umehara

It is classically known that complete flat surfaces in Euclidean 3-space are cylinders over space curves. This implies that the study of global behaviour of flat surfaces requires the study of singular points as well. If a flat surface $f$ admits singularities but its Gauss map $ν$ can be smoothly extended across the singular set, $f$ is called a frontal. In