January 2008 arXiv papers — page 6

Ariyeh H. Maller

In the CDM cosmological framework structures grow from merging with smaller structures. Merging should have observable effects on galaxies including destroying disks and creating spheroids. This proceeding aims to give a brief overview of how mergers occur in cosmological simulations. In this regard it is important to understand that dark matter halo mergers

T. D. Kitching, A. F. Heavens, L. Verde, P. Serra

In this paper we investigate the potential of 3D cosmic shear to constrain massive neutrino parameters. We find that if the total mass is substantial (near the upper limits from LSS, but setting aside the Ly alpha limit for now), then 3D cosmic shear + Planck is very sensitive to neutrino mass and one may expect that a next generation photometric redshift su

Ariyeh H. Maller, Andreas A. Berlind, Michael Blanton, David W. Hogg

Galaxies are seen from different viewing angles and their observed properties change as a function of viewing angle. In many circumstances we would rather know the intrinsic properties of galaxies - those properties that do not depend on viewing angle. For a large sample of galaxies it is possible to recover the intrinsic properties of galaxies, statisticall

Jonathan Braithwaite

An arbitrary initial magnetic field in an A star evolves into a stable equilibrium. Simulations are presented of the formation of non-axisymmetric equilibria consisting of twisted flux tubes meandering under the surface of the star, and analytic arguments are given relating the stability and form of these equilibria. These results may help to explain observa

H. Jang-Condell

Planets embedded in optically thick passive accretion disks are expected to produce perturbations in the density and temperature structure of the disk. We calculate the magnitudes of these perturbations for a range of planet masses and distances. The model predicts the formation of a shadow at the position of the planet paired with a brightening just beyond

Elizabeth R. Stanway, Malcolm N. Bremer, Valentina Squitieri, Laura S. Douglas

We present a survey of bright optical dropout sources in two deep, multiwavelength surveys comprising eleven widely-separated fields, aimed at constraining the galaxy luminosity function at z~7 for sources at 5-10L*(z=6). Our combined survey area is 225 arcmin^2 to a depth of J=24.2 (AB, 3 sigma) and 135 arcmin^2 to J=25.3 (AB, 4 sigma). We find that infrare

Daniel R. Ward, Naomi J. Halas, Jacob W. Ciszek, James M. Tour

Electronic conduction through single molecules is affected by the molecular electronic structure as well as by other information that is extremely difficult to assess, such as bonding geometry and chemical environment. The lack of an independent diagnostic technique has long hampered single-molecule conductance studies. We report simultaneous measurement of

Nick Dungey

Given a power-bounded linear operator T in a Banach space and a probability F on the non-negative integers, one can form a `subordinated' operator S = \sum_k F(k) T^k. We obtain asymptotic properties of the subordinated discrete semigroup (S^n: n=1,2,...) under certain conditions on F. In particular, we study probabilities F with the property that S sati

Winfried Just, German Enciso

Boolean networks have been the object of much attention, especially since S. Kauffman proposed them in the 1960's as models for gene regulatory networks. These systems are characterized by being defined on a Boolean state space and by simultaneous updating at discrete time steps. Of particular importance for biological applications are networks in which

PHENIX Collaboration, A. Adare

Neutral pion transverse momentum (pT) spectra at mid-rapidity (|y| < 0.35) were measured in Cu+Cu collisions at \sqrt s_NN = 22.4, 62.4, and 200 GeV. Relative to pi -zero yields in p+p collisions scaled by the number of inelastic nucleon-nucleon collisions (Ncoll) at the respective energies, the pi-zero yields for pT \ge 2 GeV/c in central Cu+Cu collisions a

Randall L. McEntaffer, Webster Cash

The Cygnus X-ray Emission Spectroscopic Survey (CyXESS) sounding rocket payload was launched from White Sands Missile Range on 2006 November 20 and obtained a high resolution spectrum of the Cygnus Loop supernova remnant in the soft X-rays. The novel X-ray spectrograph incorporated a wire-grid collimator feeding an array of gratings in the extreme off-plane

F. C. Lombardo, F. D. Mazzitelli, P. I. Villar

We review recent work on the Casimir interaction energy between cylindrical shells. We include proposals for future experiments involving cylinders, such us a null experiment using quasi-concentric cylinders, a cylinder in front a conducting plate, and a cylindrical version of the rack and pinion powered by Casimir lateral force. We also present an exact for

Haruka Tanji, Jonathan Simon, Saikat Ghosh, Vladan Vuletić

We point out that, if one accepts the validity of quantum mechanics, the Bell parameter for the polarization state of two photons can be measured in a simpler way than by the standard procedure [Clauser, Horne, Shimony, and Holt, Phys. Rev. Lett. 23, 880 (1969)]. The proposed method requires only two measurements with parallel linear-polarizer settings for A

Masaki Tsukamoto

We show estimates of the &#34;macroscopic dimension&#34; of the $\ell^p$-ball with respect to the $\ell^q$-norm.

Thomas K. Gaisser

The Roma International Conference on Astroparticle Physics covered gamma-ray astronomy, air shower experiments and neutrino astronomy on three successive days. I organize my brief summary comments into four topics that cut across these three techniques. They are detector calibration, galactic sources, extra-galactic sources and cosmology.

PHENIX Collaboration, A. Adare

Azimuthal angle (Delta phi) correlations are presented for a broad range of transverse momentum (0.4 < pT < 10 GeV/c) and centrality (0-92%) selections for charged hadrons from di-jets in Au+Au collisions at sqrt(s_NN) = 200 GeV. With increasing pT, the away-side Delta phi distribution evolves from a broad and relatively flat shape to a concave shape, then t

Pierre Moulin

When information is to be transmitted over an unknown, possibly unreliable channel, an erasure option at the decoder is desirable. Using constant-composition random codes, we propose a generalization of Csiszar and Korner&#39;s Maximum Mutual Information decoder with erasure option for discrete memoryless channels. The new decoder is parameterized by a weigh

G. Szabo, A. Szolnoki, I. Borsos

Formation and competition of associations are studied in a six-species ecological model where each species has two predators and two prey. Each site of a square lattice is occupied by an individual belonging to one of the six species. The evolution of the spatial distribution of species is governed by iterated invasions between the neighboring predator-prey

Thomas K. Gaisser

This paper is the written version of the rapporteur talk on Section HE-2, muons and neutrinos, presented at the 30th International Cosmic Ray Conference, Merida, Yucatan, July 11, 2007. Topics include atmospheric muons and neutrinos, solar neutrinos and astrophysical neutrinos as well as calculations and instrumentation related to these topics.

Charles Bonatto, Eduardo Bica, Joao F. C. Santos

We report the discovery of a new open cluster (OC) in the Galaxy at $\ell=167.0^\circ$ and $b=-1.0^\circ$. Its field includes the planetary nebula (PN) PK 167-0.1. We study the possible associations of the PN/OC pairs NGC 2818/NGC 2818A, NGC 2438/M 46 (NGC 2437), PK 6+2.5/NGC 6469, as well as of the PN PK 167-0.1 with New Cluster 1. The analyses are based on

S. G. Rajeev

We propose a relativistically invariant wave equation for the Skyrme soliton. It is a differential equation on the space $R^{1,3}\times S^3$ which is invariant under the Lorentz group and isospin. The internal variable valued in $SU(2)\approx S^3$ describes the orientation of the soliton. The mass of a particle of spin and isospin both equal to $j={1\over 2}

Theodor Pribulla, Slavek M. Rucinski

We present two-dimensional (radial velocity, orbital phase) spectroscopic results for the very low mass-ratio close binary AW UMa which strongly indicate that the spectroscopic mass ratio (q_sp = 0.10) does not agree with the photometrically derived one and that the widely adopted contact binary model appears to experience serious inconsistencies and limitat

Ben Craps, Frederik De Roo, Oleg Evnin

We continue the study of time-dependent Hamiltonians with an isolated singularity in their time dependence, describing propagation on singular space-times. In previous work, two of us have proposed a &#34;minimal subtraction&#34; prescription for the simplest class of such systems, involving Hamiltonians with only one singular term. On the other hand, Hamilt

S. Colafrancesco

We derive the SZ effect arising in radio-galaxy lobes that are filled with high-energy, non-thermal electrons. We provide here quantitative estimates for SZ effect expected from the radio galaxy lobes by normalizing it to the Inverse-Compton light, observed in the X-ray band, as produced by the extrapolation to low energies of the radio emitting electron spe

Pasquale Blasi

This paper summarizes highlights of the OG1 session of the 30th International Cosmic Ray Conference, held in Merida (Yucatan, Mexico). The subsessions (OG1.1, OG1.2, OG1.3, OG1.4 and OG1.5) summarized here were mainly devoted to direct measurements, acceleration and propagation of cosmic rays.

Derek F. Holt, Sarah Rees, Michael Shapiro

We prove that a group has word problem that is a growing context-sensitive language precisely if its word problem can be solved using a non-deterministic Cannon&#39;s algorithm (the deterministic algorithms being defined by Goodman and Shapiro). We generalise their results to find many examples of groups not admitting non-deterministic Cannon&#39;s algorithm

G. Oliveira-Neto, G. F. Sousa

The Wyman&#39;s solution depends on two parameters, the mass $M$ and the scalar charge $σ$. If one fixes $M$ to a positive value, say $M_0$, and let $σ^2$ take values along the real line it describes three different types of spacetimes. For $σ^2 >0$ the spacetimes are naked singularities, for $σ^2 = 0$ one has the Schwarzschild black hole of mass $M_0$ and f

E. Pollmann, Th. Rivinius

We report H-alpha observations of zeta Tauri, taken between late 2000 and early 2006. Next to extending existing long-term montioring of the disk state of this star we report an intermediate timescale of about 69 days to be present in the V/R variations of the Halpha line. The observational data will be published together with this manuscript.

G. Seibold

Based on the Kotliar-Ruckenstein slave-boson scheme we develop a configuration-interaction (CI) approach which is suitable to improve the energy of symmetry-broken saddle-point solutions. The theory is applied to spin-polaron states in the Hubbard model and compared with analogous results obtained within the Hartree-Fock approximation. In addition we show th

Kees de Jager

Elastic electron scattering off $^3$He and $^4$He has recently been studied at forward and backward scattering angles in Hall A at JLab. The results will provide accurate data on the elastic form factors, charge and magnetic for $^3$He and charge only for $^4$He, up to squared momentum transfer $Q^2$-values of 3.2 GeV$^2$.

S. Hallerberg, H. Kantz

We investigate the predictability of extreme events in time series. The focus of this work is to understand under which circumstances large events are better predictable than smaller events. Therefore we use a simple prediction algorithm based on precursory structures which are identified using the maximum likelihood principle. Using the receiver operator ch

Gianluca Geloni, Evgeni Saldin, Evgeni Schneidmiller, Mikhail Yurkov

This article describes a complete theory of spatial coherence for undulator radiation sources. Current estimations of coherence properties often assume that undulator sources are quasi-homogeneous, like thermal sources, and rely on the application of the van Cittert-Zernike theorem for calculating the degree of transverse coherence. Such assumption is not ad

Ora E. Percus, Jerome K. Percus

Given two sets of data which lead to a similar statistical conclusion, the Simpson Paradox describes the tactic of combining these two sets and achieving the opposite conclusion. Depending upon the given data, this may or may not succeed. Inverse Simpson is a method of decomposing a given set of comparison data into two disjoint sets and achieving the opposi

F. Delduc, E. Ivanov

This talk summarizes the study of superfield gaugings of isometries of extended supersymmetric mechanics in hep-th/0605211, hep-th/0611247 and arXiv:0706.0706. The gauging procedure provides a manifestly supersymmetric realization of d=1 automorphic dualities which interrelate various irreducible off-shell multiplets of d=1 extended supersymmetry featuring t

Kees de Jager

Preliminary results of a selected few recent experiments at JLab are presented.

T. Wiegelmann, A. Lagg, S. K. Solanki, B. Inhester

We compare magnetic field extrapolations from a photospheric magnetogram with the observationally inferred structure of magnetic loops in a newly developed active region. This is the first time that the reconstructed 3D-topology of the magnetic field is available to test the extrapolations. We compare the observations with potential fields, linear force-free

Devang A. Joshi, R. Nagalakshmi, S. K. Dhar, A. Thamizhavel

Single crystals of R$_2$CoGa$_8$ series of compounds were grown, for the first time, by high temperature solution growth (flux) method. These compounds crystallize in a tetragonal crystal structure with the space group $P4/mmm$. It has been found that R$_2$CoGa$_8$ phase forms only with the heavier rare earths, starting from Gd with a relatively large $c/a$

Sanjeev Kumar, Arno P. Kampf

We study the effect of quenched disorder on the ordering of orbital and magnetic degrees of freedom in a two-dimensional, two-band double-exchange model for $e_g$ electrons coupled to Jahn-Teller distortions. Using a real-space Monte Carlo method, we find that disorder can induce a short-range ordering of the orbital degrees of freedom near 30% hole doping.

A. Budzanowski, M. Fidelus, D. Filges, F. Goldenbaum

The energy and angular dependence of double differential cross sections was measured for p,d,t,He,Li,Be, and B isotopes produced in collisions of 1.2 and 1.9 GeV protons with Au target. The shape of the spectra and angular distributions almost does not change in the beam energy range from 1.2 to 2.5 GeV, however, the absolute value of the cross sections incr

A. Sollima, B. Lanzoni, G. Beccari, F. R. Ferraro

Context. Blue Stragglers Stars (BSSs) are thought to form in globular clusters by two main formation channels: i) mergers induced by stellar collisions and ii) coalescence or mass-transfer between companions in binary systems. The detailed study of the BSS properties is therefore crucial for understanding the binary evolution mechanisms, and the complex inte

Marcel Vos

The SiLC - Silicon for the Linear Collider - collaboration aims to develop silicon detector technology for tracking in the international linear collider experiments. The R & D programme involves a substantial effort in simulation of the response of detector designs. In this contribution, an overview of ongoing efforts in this area is given.

V. A. Karmanov, J. -F. Mathiot, A. V. Smirnov

Within the framework of the covariant formulation of light-front dynamics, we develop a general non-perturbative renormalization scheme based on the Fock decomposition of the state vector and its truncation. The counterterms and bare parameters needed to renormalize the theory depend on the Fock sectors. We present a general strategy in order to calculate th

Jorge Sotomayor

New results are established here on the phase portraits and bifurcations of the kinematic model in a system of ODE&#39;s, first presented by H.K. Wilson in his 1971 book, and by him attributed to L. Markus (unpublished). A new, self-sufficient, study which extends Wilson&#39;s result and allows an essential conclusion for the applicability of the model is re

K. S. D. Beach, Matthieu Mambrini, Fabien Alet

Quantum Monte Carlo methods are sophisticated numerical techniques for simulating interacting quantum systems. In some cases, however, they suffer from the notorious &#34;sign problem&#34; and become too inefficient to be useful. A recent publication [J. Wojtkiewicz, Phys. Rev. B 75, 174421 (2007)] claims to have solved the sign problem for a certain class o

Henning Schomerus, Eric Lutz

We develop a theory describing the dynamics of quantum kicked rotators (modelling cold atoms in a pulsed optical field) which are subjected to combined amplitude and timing noise generated by a renewal process (acting as an engineered reservoir). For waiting-time distributions of variable exponent (Lévy noise), we demonstrate the existence of a regime of non

H. Beuther, D. Semenov, Th. Henning, H. Linz

APEX single-dish observations at sub-millimeter wavelengths toward a sample of massive star-forming regions reveal that C2H is almost omni-present toward all covered evolutionary stages from Infrared Dark Clouds via High-Mass Protostellar Objects to Ultracompact HII regions. High-resolution data from the Submillimeter Array toward one hot-core like High-Mass

T. Morel, S. Hubrig, M. Briquet

Evolutionary models for massive stars, accounting for rotational mixing effects, do not predict any core-processed material at the surface of B dwarfs with low rotational velocities. Contrary to theoretical expectations, we present a detailed and fully-homogeneous, NLTE abundance analysis of 20 early B-type dwarfs and (sub)giants that reveals the existence o

G. Manfredi, P. -A. Hervieux

The quantum coherence of a Bose-Einstein condensate is studied using the concept of quantum fidelity (Loschmidt echo). The condensate is confined in an elongated anharmonic trap and subjected to a small random potential such as that created by a laser speckle. Numerical experiments show that the quantum fidelity stays constant until a critical time, after wh

R. Crespo, A. Deltuva, E. Cravo, M. Rodriguez-Gallardo

Full Faddeev-type calculations are performed for $^{11}$Be breakup on proton target at 38.4, 100, and 200 MeV/u incident energies. The convergence of the multiple scattering expansion is investigated. The results are compared with those of other frameworks like Distorted Wave Impulse Approximation that are based on an incomplete and truncated multiple scatte

V. N. Zirakashvili, V. S. Ptuskin

We investigate the diffusive shock acceleration in the presence of the non-resonant streaming instability introduced by Bell (2004). The numerical MHD simulations of the magnetic field amplification combined with the analytical treatment of cosmic ray acceleration permit us to calculate the maximum energy of particles accelerated by high-velocity supernova s

Charles D. Hill, Henry L. Haselgrove

In this paper, we show that the ability to switch globally between two 2-local Hamiltonians on n qubits is sufficient for achieving universal unitary dynamics on those n qubits. Of the two Hamiltonians used in the construction, one is comprised of nearest-neighbour two-qubit interactions on a one-dimensional chain, the other is comprised of single-qubit inte

V. A. Karnaukhov, H. Oeschler, A. Budzanowski, S. P. Avdeyev

Critical temperature Tc for the nuclear liquid-gas phase transition is stimated both from the multifragmentation and fission data. In the first case,the critical temperature is obtained by analysis of the IMF yields in p(8.1 GeV)+Au collisions within the statistical model of multifragmentation (SMM). In the second case, the experimental fission probability f

Luísa Arruda, Fernando Barão, Patrícia Goncalves, Rui Pereira

The Alpha Magnetic Spectrometer (AMS) to be installed on the International Space Station (ISS) will be equipped with a proximity Ring Imaging Cherenkov (RICH) detector for measuring the velocity and electric charge of the charged cosmic particles. This detector will contribute to the high level of redundancy required for AMS as well as to the rejection of al

Jean-Alexandre Long, Vincent Daanen, Alexandre Moreau-Gaudry, Jocelyne Troccaz

This paper analyzes the impact of using 2D or 3D ultrasound on the efficiency of prostate biopsies. The evaluation is performed on home-made phantoms. The study shows that the accuracy is significantly improved.

Gilles Grégoire, Bruno Lucas, Michel Barat, Jacqueline Fayeton

UV photoinduced fragmentation of protonated aromatics amino acids have emerged the last few years, coming from a situation where nothing was known to what we think a good understanding of the optical properties. We will mainly focus this review on the tryptophan case. Three groups have mostly done spectroscopic studies and one has mainly been involved in dyn

Henri Gouin

We consider the wetting transition on a planar surface in contact with a semi-infinite fluid. In the classical approach, the surface is assumed to be solid, and when interaction between solid and fluid is sufficiently short-range, the contribution of the fluid can be represented by a surface free energy with a density of the form Phi(rho_s), where rho_s is t

Babatunde O. Okunoye

Deoxyribonucleic acid is increasingly being understood to be an informational molecule, capable of information processing.It has found application in the determination of non-deterministic algorithms and in the design of molecular computing devices. This is a theoretical analysis of the mathematical properties and relations of the molecules which constitutin

Franco Pellegrini, Simone Montangero, Giuseppe E. Santoro, Rosario Fazio

By gradually changing the degree of the anisotropy in a XXZ chain we study the defect formation in a quantum system that crosses an extended critical region. We discuss two qualitatively different cases of quenches, from the antiferromagnetic to the ferromagnetic phase and from the critical to the antiferromegnetic phase. By means of time-dependent DMRG simu

A. C. Becker, E. Agol, N. M. Silvestri, J. J. Bochanski

We report on 2MASS J01542930+0053266, a faint eclipsing system composed of two M dwarfs. The variability of this system was originally discovered during a pilot study of the 2MASS Calibration Point Source Working Database. Additional photometry from the Sloan Digital Sky Survey yields an 8-passband lightcurve, from which we derive an orbital period of 2.6390

P. Jovanović, A. F. Zakharov, L. Č. Popović, T. Petrović

We consider the influence of microlensing on different spectral bands of lensed QSOs. We assumed that the emitting X-ray, UV and optical regions are different in size, but that the continuum emission in these spectral bands is originating from an accretion disc. Estimations of the time scales for microlensing and flux amplification in different bands are giv

Riccardo Franco

In the present article we introduce a quantum mechanism which is able to describe the creation of correlations in the evaluation of random independent events: such correlations, known as positive and negative recency, correspond respectively to the hot hand&#39;s and to the gambler&#39;s fallacies. Thus we propose a description of these effects in terms of q

Babatunde O. Okunoye

Statistical tests were conducted on 1,000 numbers generated from the genome of Bacteriophage T4, obtained from GenBank with accession number AF158101.The numbers passed the non-parametric, distribution-free tests.Deoxyribonucleic acid was discovered to be a random number generator, existent in nature.

O. Matsumoto, A. Utsuki, A. Tsukada, H. Yamamoto

In this article, we report the superconductivity in T&#39;-RE2CuO4 (RE = Pr, Nd, Sm, Eu, and Gd), which have been for a long time believed as a Mott insulator. Our discovery was achieved by using metal-organic decomposition (MOD), an inexpensive and easy-to-implement thin-film process. The keys to prepare the superconducting films are firing with low partial

N. N. Chugai

Formation of circumstellar lines of Na I and Ca II in type Ia supernovae is studied for the case, when supernova explodes in a binary system with a red giant. The model suggests a spherically-symmetric wind and takes into account ionization and heating of the wind by X-rays from the shock wave and by gamma-quanta of ^{56}Ni radioactive decay. For the wind de

Gregory Lehaut, Francesca Gullminelli, Olivier Lopez

It has been proposed that multifragmentation can be related to the liquid-gas phase transition of nuclear matter. We study the statistical properties of finite nuclear matter near the phase transition with the help of a Lattice Gas Model (LGM). The original version of LGM with only one type of charge-neutral particles is well known to feature the properties

Patricia A. Whitelock, Michael W. Feast, Floor van Leeuwen

Published data for large amplitude asymptotic giant branch variables in the Large Magellanic Cloud are re-analysed to establish the constants for an infrared (K) period-luminosity relation of the form: Mk=rho[log P-2.38] + delta. A slope of rho=-3.51+/-0.20 and a zero point of delta=-7.15+/-0.06 are found for oxygen-rich Miras (if a distance modulus of 18.39

Jacco H. Snoeijer, Bruno Andreotti

We discuss the equilibrium condition for a liquid that partially wets a solid on the level of intermolecular forces. Using a mean field continuum description, we generalize the capillary pressure from variation of the free energy and show at what length scale the equilibrium contact angle is selected. After recovering Young&#39;s law for homogeneous substrat

P. A. Evans, A. P. Beardmore, M. R. Goad, J. P. Osborne

Since GRBs fade rapidly, it is important to publish accurate, precise positions at early times. For Swift-detected bursts, the best promptly available position is most commonly the X-ray Telescope (XRT) position. We present two processes, developed by the Swift team at Leicester, which are now routinely used to improve the precision and accuracy of the XRT p

Bernard Helffer, Yuri A. Kordyukov

We consider a periodic magnetic Schrödinger operator on a noncompact Riemannian manifold $M$ such that $H^1(M, \RR)=0$ endowed with a properly discontinuous cocompact isometric action of a discrete group. We assume that there is no electric field and that the magnetic field has a periodic set of compact magnetic wells. We review a general scheme of a proof o

Marcel Griesemer, David Hasler

For a large class of quantum mechanical models of matter and radiation we develop an analytic perturbation theory for non-degenerate ground states. This theory is applicable, for example, to models of matter with static nuclei and non-relativistic electrons that are coupled to the UV-cutoff quantized radiation field in the dipole approximation. If the lowest

N. Przybilla, M. F. Nieva, U. Heber, M. Firnstein

Context: Hyper-velocity stars move so fast that only a supermassive black hole (SMBH) seems to be capable to accelerate them. Hence the Galactic centre (GC) is their only suggested place of origin. Edelmann et al. (2005) found the early B-star HE0437-5439 to be too short-lived to have reached its current position in the Galactic halo if ejected from the GC,

R. Arlt

A variety of magnetohydrodynamic mechanisms that may play a role in magnetic, chemically peculiar (mCP) stars is reviewed. These involve dynamo mechanisms in laminar flows as well as turbulent environments, and magnetic instabilities of poloidal and toroidal fields as well as combinations of the two. While the proto-stellar phase makes the survival of primor

Alexander Knebe, Chris Power

We report on a correlation between virial mass M and spin parameter lambda for dark matter halos forming at redshifts z > 10. We find that the spin parameter decreases with increasing halo mass. Interestingly, our analysis indicates that halos forming at later times do not exhibit such a strong correlation, in agreement with the findings of previous studies.

C. Kramer, R. Moreno, A. Greve

The planets Uranus and Neptune with small apparent diameters are primary calibration standards. We investigate their variability at ~90 GHz using archived data taken at the IRAM 30m telescope during the 20 years period 1985 to 2005. We calibrate the planetary observations against non-variable secondary standards (NGC7027, NGC7538, W3OH, K3-50A) observed almo

O. Broche, E. Jespers, C. Polcino Milies, M. Ruiz

Let $R$ be a commutative ring, $G$ a group and $RG$ its group ring. Let $\vp : RG\to RG$ denote the $R$-linear extension of an involution $\vp$ defined on $G$. An element $x$ in $RG$ is said to be $\vp$-antisymmetric if $\vp (x) = -x$. A characterization is given of when the $\vp$-antisymmetric elements of $RG$ commute. This is a completion of earlier work.

A. N. Aleshin, I. P. Shcherbakov, E. L. Alexandrova, E. A. Lebedev

We report on the effect of electric field on the photoluminescence, PL, from a composite consisting of a conjugated polymer mixed with zinc oxide nanoparticles. We have found that in the absence of electric field PL emission from the composite film has two maxima in the blue and green-yellow regions. Application of a voltage bias to planar gold electrodes su

Jiang-Hai Qian, Ding-Ding Han

In this paper we consider nodes in network are heterogeneous and the link between nodes is caused by the potential dynamical demand of the nodes. Such demand can be measured by gravitation which increases with the heterogeneous strength of node and decreases with the geographical distance. Based on this, we propose a new model for spatial network from the vi

Sujin Babu, Jean-Christophe Gimel, Taco Nicolai

Irreversible diffusion limited cluster aggregation (DLCA) of hard spheres was simulated using Brownian cluster dynamics. Bound spheres were allowed to move freely within a specified range, but no bond breaking was allowed. The structure and size distribution of the clusters was investigated before gelation. The pair correlation function and the static struct

A. Bonanno, S. Benatti, R. Claudi, S. Desidera

A clear detection of excess of power, providing a substantial evidence for solar-like oscillations in the G5 subgiant \muher{}, is presented. This star was observed over seven nights with the SARG echelle spectrograph operating with the 3.6-m Italian TNG Telescope, using an iodine absorption cell as a velocity reference. A clear excess of power centered at 1

S. Fukushima, T. Sato, D. Akahoshi, H. Kuwahara

We have succeeded in preparing A-site ordered- and disordered-Y1/4Sr3/4CoO3-d with various oxygen deficiencies delta, and have made comparative study of their structural and physical properties. In the A-site ordered structure, oxygen vacancies order, and d = 0.34 sample shows a weak ferromagnetic transition beyond 300 K. On the other hand, in the A-site dis

K. Akabli, H. T. Diep

The magnetic phase transition is experimentally known to give rise to an anomalous temperature-dependence of the electron resistivity in ferromagnetic crystals. Phenomenological theories based on the interaction between itinerant electron spins and lattice spins have been suggested to explain these observations. In this paper, we show by extensive Monte Carl

Betsy Jane Becker, Meng-Jia Wu

Research on methods of meta-analysis (the synthesis of related study results) has dealt with many simple study indices, but less attention has been paid to the issue of summarizing regression slopes. In part this is because of the many complications that arise when real sets of regression models are accumulated. We outline the complexities involved in synthe

Nami Sakai, Takeshi Sakai, Yuri Aikawa, Satoshi Yamamoto

The millimeter-wave rotational emission lines (4(04)-3(03) and 5(05)-4(04)) of protonated carbon dioxide, HCO2+(HOCO+), has been detected toward the low-mass class 0 protostar IRAS 04368+2557 in L1527 with the IRAM 30 m telescope. This is the first detection of HCO2+ except for the Galactic Center clouds. The column density of HCO2+ averaged over the beam si

W. Saunders

Cosmic shear offers a remarkbly clean way to measure the equation of state of the Universe and its evolution. Resolution over a wide field is paramount, and Antarctica offers unique possibilities in this respect. There is an order of magnitude gain in speed over temperate sites, or a factor three in surface density. This means that PILOT outperforms much lar

Matthias Aschenbrenner, Christopher J. Hillar

A \textit{symmetric ideal} $I \subseteq R = K[x_1,x_2,...]$ is an ideal that is invariant under the natural action of the infinite symmetric group. We give an explicit algorithm to find Gröbner bases for symmetric ideals in the infinite dimensional polynomial ring $R$. This allows for symbolic computation in a new class of rings. In particular, we solve the

W. Saunders, P. R. Gillingham, A. J. McGrath, J. W. V. Storey

The proposed design for PILOT is a general-purpose, wide-field 1 degree 2.4m, f/10 Ritchey-Chretien telescope, with fast tip-tilt guiding, for use 0.5-25 microns. The design allows both wide-field and diffraction-limited use at these wavelengths. The expected overall image quality, including median seeing, is 0.28-0.3&#34; FWHM from 0.8-2.4 microns. Point so

J. Chen, Y. J. Chen, J. Fan, J. Liu

We present a new theory that the molecular high order harmonic generation in an intense laser field is determined by molecular internal symmetry and momentum distribution of the tunneling-ionized electron. The molecular internal symmetry determines the quantum interference form of the returning electron inside the molecule. The electron momentum distribution

Michael Springborg, Bernard Kirtman

Mathematical arguments are presented that give a unique answer to the question in the title. Subsequently, the mathematical analysis is extended using results of detailed model calculations that, in addition, throw further light on the consequences of the analysis. Finally, through a comparison with various recent studies, many of the latter are given a new

Rajendra R. Zope, Tunna Baruah, Mark R. Pederson, B. I. Dunlap

The static dielectric response of C60, C180, C240, C540, C720, C960, C1500, and C2160 fullerenes is characterized by an all-electron density-functional method. First, the screened polarizabilities of C60, C180, C240, and C540, are determined by the finite-field method using Gaussian basis set containing 35 basis functions per atom. In the second set of calcu

Teruaki Kitano, Takayuki Morifuji

In this paper, we study a series of $L^2$-torsion invariants from the viewpoint of the mapping class group of a surface. We establish some vanishing theorems for them. Moreover we explicitly calculate the first two invariants and compare them with hyperbolic volumes.

Jun&#39;ichi Wakou, Akinori Ochiai, Masaharu Isobe

We present a Langevin approach to describe the steady-state dynamics of one-dimensional granular media fluidized by a vibrating bottom plate. We adopt a linear Langevin equation to describe the motion of the center of mass. Within this framework, we derive analytical expressions for several macroscopic quantities. We also predict the power spectrum for the h

Tim Gould, Ken Simpkins, John F. Dobson

In recent years intercalated and pillared graphitic systems have come under increasing scrutiny because of their potential for modern energy technologies. While traditional \emph{ab initio} methods such as the LDA give accurate geometries for graphite they are poorer at predicting physicial properties such as cohesive energies and elastic constants perpendic

Manas Tungare, Manuel Perez-Quinones

As users begin to use many more devices for personal information management (PIM) than just the traditional desktop computer, it is essential for HCI researchers to understand how these devices are being used in the wild and their roles in users&#39; information environments. We conducted a study of 220 knowledge workers about their devices, the activities t

Harry K. Hahn

The natural numbers divisible by the Prime Factors 2, 3, 5, 11, 13 and 17 lie on defined spiral graphs, which run through the Square Root Spiral. A mathematical analysis shows, that these spiral graphs are defined by specific quadratic polynomials. Basically all natural number which are divisible by the same prime factor lie on such spiral graphs. And these

A. G. Mal&#39;shukov, C. S. Chu

The Josephson tunneling through a 2D normal contact with the spin-orbit split conduction band has been studied in the diffusive regime. Linearized Usadel equations for triplet components of the pairing function revealed a striking similarity to the equations of spin diffusion driven by the electric field in normal metals. Consequently, we predict that the ou

Emi Miyata, Kuniaki Masai, John P. Hughes

We present an analysis of the Suzaku observation of the northeastern rim of the Cygnus Loop supernova remnant. The high detection efficiency together with the high spectral resolution of the Suzaku X-ray CCD camera enables us to detect highly-ionized C and N emission lines from the Cygnus Loop. Given the significant plasma structure within the Suzaku field o

L. F. Wei, J. R. Johansson, L. X. Cen, S. Ashhab

We propose an approach to coherently transfer populations between selected quantum states in one- and two-qubit systems by using controllable Stark-chirped rapid adiabatic passages (SCRAPs). These {\it evolution-time insensitive} transfers, assisted by easily implementable single-qubit phase-shift operations, could serve as elementary logic gates for quantum

Raza M. Syed

The following is the very first set of the series in &#39;Problems and Solutions in a Graduate Course in Classical Electrodynamics&#39;. In each of the sets of the problems we intend to follow a theme, which not only makes it unique but also deals with the investigation of a certain class of problems in a thorough and rigorous manner. Figures are not include

C. Baruteau, F. Masset

We investigate the tidal interaction between a low-mass planet and a self-gravitating protoplanetary disk, by means of two-dimensional hydrodynamic simulations. We first show that considering a planet freely migrating in a disk without self-gravity leads to a significant overestimate of the migration rate. The overestimate can reach a factor of two for a dis

Li-Gang Wang

In this paper, we present the equivalent medium theory by using the linear response theory. It is found that, under the condition of the linear response, a series of different media with different refractive indices $n_{i}(ω)$ and lengths $d_{i}$ can be equivalent to an effective medium with the volume-averaged refractive index $\frac{1}{D}\sum_{i=1}^{N}n_{i