November 2005 arXiv papers — page 30

Curtis Struck

The study of colliding galaxies has progressed rapidly in the last few years, driven by observations with powerful new ground and space-based instruments. These instruments have used for detailed studies of specific nearby systems, statistical studies of large samples of relatively nearby systems, and increasingly large samples of high redshift systems. Foll

Filippo Fraternali, James Binney

Recent HI observations reveal that the discs of spiral galaxies are surrounded by extended gaseous haloes. This extra-planar gas reaches large distances (several kpc) from the disc and shows peculiar kinematics (low rotation and inflow). We have modelled the extra-planar gas as a continuous flow of material from the disc of a spiral galaxy into its halo regi

Lev Titarchuk, Pascal Chardonnet

Compton Gamma Ray Observatory, OSSE, SMM, TGRS, balloon and recent INTEGRAL data reveal a feature of the 0.511 MeV annihilation radiation of the Galactic Center with a flux of approximately 5x 10^{-4}~0.511 MeV photons cm^{-2} s^{-1}. We argue that e+e- pairs can be generated when the X-ray radiation photons and ~10-30 MeV photons interact with each other in

G. Covone, J. -P. Kneib, G. Soucail, J. Richard

(abridged) We present extensive multi-color imaging and low resolution VIMOS Integral Field Unit spectroscopic observations of the X-ray luminous cluster Abell 2667 (z=0.233). An extremely bright giant gravitational arc (z=1.0334) is easily identified as part of a triple image system and other fainter multiple images are also revealed by the HST-WFPC2 images

Carsten Weidner, Pavel Kroupa

We demonstrate that the mass of the most massive star in a cluster correlates non-trivially with the cluster mass. A simple algorithm according to which a cluster is filled up with stars that are chosen randomly from the standard IMF but sorted with increasing mass yields an excellent description of the observational data. Algorithms based on random sampling

Julia M. Comerford, Massimo Meneghetti, Matthias Bartelmann, Mischa Schirmer

Although N-body simulations of cosmic structure formation suggest that dark matter halos have density profiles shallower than isothermal at small radii and steeper at large radii, whether observed galaxy clusters follow this profile is still ambiguous. We use one such density profile, the asymmetric NFW profile, to model the mass distributions of 11 galaxy c

Pasquale Temi, Fabrizio Brighenti, William G. Mathews

Mid-infrared observations (3.6 - 24 microns) of normal giant elliptical galaxies with the Spitzer space telescope are consistent with pure populations of very old stars with no evidence of younger stars. Most of the stars in giant elliptical galaxies are old but the mean stellar age determined from Balmer absorption in optical spectra can appear much younger

Martin C. Weisskopf, John P. Hughes

We present a review of the first six years of Chandra X-ray Observatory observations of supernova remnants. From the official "first-light" observation of Cassiopeia A that revealed for the first time the compact remnant of the explosion, to the recent million-second spectrally-resolved observation that revealed new details of the stellar composition

Pascal Borde, Wesley Traub

Following the tracks of Malbet, Yu, & Shao (1995} on dark hole algorithms, we present analytical methods to measure and correct the speckle noise behind an ideal coronagraph. We show that, in a low aberration regime, wavefront sensing can be accomplished with only three images, the next image being fully corrected (no iterative process needed). The only hard

N. J. Turner, K. Willacy, G. Bryden, H. W. Yorke

The effects of turbulence on the mixing of gases and dust in the outer Solar nebula are examined using 3-D MHD calculations in the shearing-box approximation with vertical stratification. The turbulence is driven by the magneto-rotational instability. The magnetic and hydrodynamic stresses in the turbulence correspond to an accretion time at the midplane abo

B. Willems

The basic theory of dynamic tides in close binaries is reviewed. Particular attention is paid to resonances between dynamic tides and free oscillation modes and to the role of the apsidal-motion rate in probing the internal structure of binary components. The discussed effects are generally applicable to stars across the entire Hertzsprung-Russell diagram, i

H. A. Hirsch, U. Heber, S. J. O'Toole, F. Bresolin

We report the discovery of an unbound hyper-velocity star, US 708, in the Milky Way halo, with a heliocentric radial velocity of +708+-15km/s. A quantitative NLTE model atmosphere analysis of optical spectra obtained with LRIS at the Keck I telescope shows that US 708 is an extremely helium-rich (N(He)/N(H)=10) subluminous O type star with Teff=44500K, log g

K. O. Mason, A. J. Blustin, P. W. A. Roming

We review some of the initial data from the UVOT telescope on the Swift observatory. Statistics based on about six months of data suggest a dark burst fraction of about 50% when combining both UVOT and ground-based observations. There is evidence that some bursts have a large gamma-ray efficiency, which may be due to strong magnetic fields in their ejecta. T

Heinz Edelmann, Ralf Napiwotzki, Uli Heber, Norbert Christlieb

We report the discovery of a 16th magnitude star, HE0437-5439, with a heliocentric radial velocity of +723+-3km/s. A quantitative spectral analysis of high-resolution optical spectra obtained with the VLT and the UVES spectrograph shows that HE0437-5439 is a main sequence B-type star with Teff=20350K, log g=3.77, solar within a factor of a few helium abundan

L. J. Tacconi, R. Neri, S. C. Chapman, R. Genzel

We present sub-arcsecond resolution IRAM PdBI interferometry of eight submillimeter galaxies at redshifts from 2 to 3.4, where we detect continuum at 1mm and/or CO lines at 3 and 1 mm. The CO 3-2/4-3 line profiles in five of the sources are double-peaked, indicative of orbital motion either in a single rotating disk or of a merger of two galaxies. The millim

Arend P. N. Sluis, T. B. Williams

We report on observations of four early-type galaxies performed with the Rutgers Fabry-Perot in order to search for Planetary Nebulae (PNe) in these systems. The aim is to use the PNe as kinematic tracers of the galaxy potential. We describe our data reduction and analysis procedure and show that the proper calibration of our detection statistic is crucial i

A. Georgakakis, I. Georgantopoulos, A. Akylas

In this paper we combine archival and proprietary XMM-Newton observations (about 5deg^2) that overlap with the Sloan Digital Sky Survey to explore the nature of the moderate-z X-ray population. We focus on X-ray sources with optically red colours (g-r>0.4), which we argue are important for understanding the origin of the X-ray background. Firstly, these syst

Hrvoje Stefancic

The phenomenon of the dark energy transition between the quintessence regime ($w > -1$) and the phantom regime ($w < -1$), also known as the cosmological constant boundary crossing, is analyzed in terms of the dark energy equation of state. It is found that the dark energy equation of state in the dark energy models which exhibit the transition is {\em impli

David Merritt, Thaisa Storchi Bergmann, Andrew Robinson, Dan Batcheldor

Magain et al. (2005) argued that the host galaxy of the quasar in HE0450-2958 is substantially under-luminous given the likely mass of its nuclear black hole. Using kinematical information from the spectra of the quasar and the companion galaxy, an ultra-luminous infrared galaxy, we test the hypothesis that the black hole powering the quasar was ejected from

S. T. Megeath, L. Hartmann, K. L. Luhman, G. G. Fazio

We present IRAC 3.6, 4.5, 5.8 and 8 micron photometry for the 17 A, K and M type members of the Eta Chameleontis association. These data show infrared excesses toward six of the 15 K and M stars, indicating the presence of circumstellar disks around 40% of the stars with masses of 0.1-1 solar mass. The two A-stars show no infrared excesses. The excess emissi

D. Molteni, G. Gerardi, V. Teresi

We discuss a special case of formation of axisymmetric shocks in the accretion flow of ideal gas onto a Schwarzschild black hole: when the total energy of the flow is negative. The result of our analysis enlarges the parameter space for which these steady shocks are exhibited in the accretion of gas rotating around relativistic stellar objects. Since kepleri

Mirko Krumpe, Deirdre Coffey, Georg Egger, Francesc Vilardell

Gamma ray bursts (GRBs) are the most energetic eruptions known in the Universe. Instruments such as Compton-GRO/BATSE and the GRB monitor on BeppoSAX have detected more than 2700 GRBs and, although observational confirmation is still required, it is now generally accepted that many of these bursts are associated with the collapse of rapidly spinning massive

C. Monteserin, R. B. Barreiro, J. L. Sanz, E. Martinez-Gonzalez

A method to compute several scalar quantities of Cosmic Microwave Background maps on the sphere is presented. We consider here four type of scalars: the Hessian matrix scalars, the distortion scalars, the gradient related scalars and the curvature scalars. Such quantities are obtained directly from the spherical harmonic coefficients (alm) of the map. We als

M. Sarzi, J. Falcon-Barroso, R. L. Davies, R. Bacon

We present the emission-line fluxes and kinematics of 48 representative elliptical and lenticular galaxies obtained with our custom-built integral-field spectrograph SAURON. Hb, [OIII], and [NI] emission lines were measured using a new procedure that simultaneously fits both the stellar spectrum and the emission lines. Using this technique we can detect emis

C. Aerts, P. De Cat, J. De Ridder, H. Van Winckel

We perform a seismic study of the young massive $β$Cephei star HD 203664 with the goal to constrain its interior structure. Our study is based on a time series of 328 new Geneva 7-colour photometric data of the star spread over 496.8 days. The data confirm the frequency of the dominant mode of the star which we refine to $f_1=6.02885 $c d$^{-1}$. The mode ha

Richard de Grijs, Peter Anders

[ABRIDGED] The LMC star cluster system offers the unique opportunity to independently check the accuracy of age and mass determinations based on a number of complementary techniques, including isochrone analysis. Using our sophisticated tool for star cluster analysis based on broad-band spectral energy distributions (SEDs), we reanalyse the Hunter et al. (20

Murat Kaplan, Hasan Saygin, Piet Hut, Jun Makino

Time-symmetric integration schemes share with symplectic schemes the property that their energy errors show a much better behavior than is the case for generic integration schemes. Allowing adaptive time steps typically leads to a loss of symplecticity. In contrast, time symmetry can be easily maintained, at least for a continuous choice of time step size. I

Sanil Unnikrishnan, T. R. Seshadri

In this paper we have explored the consequences of a model of dark energy with its energy density varying exponentially with the scale factor. We first consider the model with $ ρ_ϕ \propto e^{κa} $, where $κ$ is a constant. This is a kind of generalisation of the cosmological constant model with $κ= 0$. We show that such an exponentially varying dark energy

M. Del Santo, L. Sidoli, A. Bazzano, M. Cocchi

The X-ray persistent source 1E 1743.1-2843, located in the Galactic Centre region, has been detected by all X-ray telescope above 2 keV, whereas it is not visible in the soft X-rays (i. e. Rosat) because of the high column density along the line-of-sight. Moreover, the nature of this source remains still unknown. The gamma-ray satellite INTEGRAL has long obs

A. I. Chugunov, D. G. Yakovlev

We calculate the electron shear viscosity (determined by Coulomb electron collisions) for a dense matter in a wide range of parameters typical for white dwarf cores and neutron star crusts. In the density range from ~10^3 g cm^-3 to 10^7-10^10 g cm^-3 we consider the matter composed of widely abundant astrophysical elements, from H to Fe. For higher densitie

Mami Machida, Kenji Nakamura, Ryoji Matsumoto

We carried out three-dimensional global resistive magnetohydrodynamic (MHD) simulations of the cooling instability in optically thin hot black hole accretion flows by assuming bremsstrahlung cooling. General relativistic effects are simulated by using the pseudo-Newtonian potential. Cooling instability grows when the density of the accretion disk becomes suf

L. Labadie, P. Labeye, P. Kern, I. Schanen

This paper presents the work achieved for the manufacturing and characterization of first single-mode waveguides to be used as modal filters for nulling interferometry in the mid-infrared range [4-20 um]. As very high dynamic range is mandatory for detection of Earth-like planets, modal filtering is one of the most stringent instrumental aspects. The hollow

Masayuki Tanaka, Tadayuki Kodama, Nobuo Arimoto, Ichi Tanaka

(Abridged) We present a discovery of definitive large-scale structures around RXJ0152.7--1352 at z=0.83 based on spectroscopic redshifts. In our previous papers, we reported a photometric identification of the large-scale structures at z~0.8. A spectroscopic follow-up observation was carried out on 8 selected regions covering the most prominent structures to

Krzysztof Gozdziewski, Cezary Migaszewski

We re-analyze the precision radial velocity (RV) data of HD188015, HD114729, HD190360, HD147513 and HD208487. All these stars are supposed to host Jovian companions in long-period orbits. We test a hypothesis that the residuals of the 1-planet model of the RV or an irregular scatter of the measurements about the synthetic RV curve may be explained by the exi

Huei-Ru Chen, William J. Welch, David J. Wilner, Edmund C. Sutton

We have observed a high-mass protobinary system in the hot core W3(H2O) with the BIMA Array. Our continuum maps at wavelengths of 1.4mm and 2.8mm both achieve sub-arcsecond angular resolutions and show a double-peaked morphology. The angular separation of the two sources is 1.19&#34; corresponding to 2.43X10^3 AU at the source distance of 2.04 kpc. The flux

Roberto Soria, Giuseppina Fabbiano, Alister W. Graham, Alessandro Baldi

We have studied the nuclear activity in a sample of six quiescent early-type galaxies, with new Chandra data and archival HST optical images. Their nuclear sources have X-ray luminosities ~ 10^{38} - 10^{39} erg/s (L_X/L_Edd ~ 10^{-8} - 10^{-7}), and colors or spectra consistent with accreting supermassive black holes (SMBHs)--except for the nucleus of NGC 4

Alexander Heger, Andrew Cumming, Stanford E. Woosley

We investigate marginally stable nuclear burning on the surface of accreting neutron stars as an explanation for the mHz quasi-periodic oscillations (QPOs) observed from three low mass X-ray binaries. At the boundary between unstable and stable burning, the temperature dependence of the nuclear heating rate and cooling rate almost cancel. The result is an os

Duncan A. Forbes

Various galaxy properties are not continuous over a large range in mass, but rather reveal a remarkable transition or `bimodality&#39; at a stellar mass of 3 x 10^{10} Mo. These properties include colors, stellar populations, Xray emission and mass-to-light ratios. This behavior has been interpreted as the transition from hot to cold flows by Dekel & Birnboi

G. S. Bisnovatyi-Kogan, S. G. Moiseenko, N. V. Ardeljan

Core-collapse supernovae are connected with formation of neutron stars. Part of the gravitation energy is transformed into the energy of the explosion, observed in SN II, SN Ib,c type supernovae. The mechanism of transformation is not simple, because the overwhelming majority of the energy is going into weakly interacting neutrino. The attempts to use this e

Je-An Gu

By invoking small extra dimensions as a good energy bearer, a new scenario for understanding the origin of ultrahigh-energy cosmic rays (UHECRs), from both the bottom-up and the top-down viewpoints, is proposed. We explore the possibility of generating UHECRs via Kaluza-Klein (KK) bursts, a violent energy transfer from extra dimensions to ordinary dimensions

Fumiko Yamaguchi, Kae Nemoto, William J. Munro

We propose a new scheme for quantum error correction using robust continuous variable probe modes, rather than fragile ancilla qubits, to detect errors without destroying data qubits. The use of such probe modes reduces the required number of expensive qubits in error correction and allows efficient encoding, error detection and error correction. Moreover, t

N. Gland, P. Wang, Hernan A. Makse

We investigate the Green function of two-dimensional dense random packings of grains in order to discriminate between the different theories of stress transmission in granular materials. Our computer simulations allow for a detailed quantitative investigation of the dynamics which is difficult to obtain experimentally. We show that both hyperbolic and parabo

Phil Marshall

We present a novel approach for reconstructing the projected mass distribution of clusters of galaxies from sparse and noisy weak gravitational lensing shear data. The reconstructions are regularised using knowledge gained from numerical simulations of clusters: trial mass distributions are constructed from N physically-motivated components, each of which ha

Ehud Nakar, Avishay Gal-Yam, Derek B. Fox

The recent discovery of the first four afterglows of short-hard gamma-ray bursts (SHBs), suggests that they typically result from long-lived progenitor systems. The most popular progenitor model invokes the merger of either double neutron star (DNS) binaries or neutron star-black hole (NS-BH) systems. Such events are strong sources of gravitational-waves (GW

Tao Zhou, Jian-Guo Liu, Bing-Hong Wang

In this comment, we investigate a common used algorithm proposed by Newman [M. E. J. Newman, Phys. Rev. E {\bf 64}, 016132(2001)] to calculate the betweenness centrality for all vertices. The inaccurateness of Newman&#39;s algorithm is pointed out and a corrected algorithm, also with O($MN$) time complexity, is given. In addition, the comparison of calculati

Selcuk Bayin, E. N. Glass, Jean P. Krisch

A single Israel layer can be created when two metrics adjoin with no continuous metric derivative across the boundary. The properties of the layer depend only on the two metrics it separates. By using a fractional derivative match, a family of Israel layers can be created between the same two metrics. The family is indexed by the order of the fractional deri

M. Campanelli, C. O. Lousto, P. Marronetti, Y. Zlochower

We present a new algorithm for evolving orbiting black-hole binaries that does not require excision or a corotating shift. Our algorithm is based on a novel technique to handle the singular puncture conformal factor. This system, based on the BSSN formulation of Einstein&#39;s equations, when used with a `pre-collapsed&#39; initial lapse, is non-singular at

Carlos Gershenson, Stuart A. Kauffman, Ilya Shmulevich

Evolution depends on the possibility of successfully exploring fitness landscapes via mutation and recombination. With these search procedures, exploration is difficult in &#34;rugged&#34; fitness landscapes, where small mutations can drastically change functionalities in an organism. Random Boolean networks (RBNs), being general models, can be used to explo

Max Lieblich

We use twisted sheaves and their moduli spaces to study the Brauer group of a scheme. In particular, we (1) show how twisted methods can be efficiently used to re-prove the basic facts about the Brauer group and cohomological Brauer group (including Gabber's theorem that they coincide for a separated union of two affine schemes), (2) give a new proof of de J

R. Holman, L. Mersini-Houghton

We show that the inclusion of backreaction of massive long wavelengths imposes dynamical constraints on the allowed phase space of initial conditions for inflation, which results in a superselection rule for the initial conditions. Only high energy inflation is stable against collapse due to the gravitational instability of massive perturbations. We present

Ignacio Navarro, Karel Van Acoleyen

In this paper we study long distance modifications of gravity obtained by considering actions that are singular in the limit of vanishing curvature. In particular, we showed in a previous publication that models that include inverse powers of curvature invariants that diverge for r->0 in the Schwarzschild geometry, recover an acceptable weak field limit at s

Mauricio Angel, Rafael Díaz

We construct geometric examples of N-differential graded algebras such as the algebra of differential forms of depth $N$ on an affine manifold, and $N$-flat covariant derivatives.

F. R. Klinkhamer, C. Rupp

It is shown that high-energy astrophysics can provide information on the small-scale structure of spacetime.

Mats Andersson, Elizabeth Wulcan

Given a coherent ideal sheaf $J$ we construct locally a vector-valued residue current $R$ whose annihilator is precisely the given sheaf. In case $J$ is a complete intersection, $R$ is just the classical Coleff-Herrera product. By means of these currents we can extend various results, previously known for a complete intersection, to general ideal sheaves. Co

A. J. Barr

A new method is presented for measuring the spin of selectrons and smuons at the Large Hadron Collider (LHC), using an angular variable which is sensitive to the polar angle in direct slepton pair production. This variable is invariant under boosts along the beam axis, so it can be used at the LHC despite the fact that the longitudinal boost of the centre-of

T. Bourdel, T. Donner, S. Ritter, A. Öttl

We observe the build-up of a matter wave interference pattern from single atom detection events in a double-slit experiment. The interference arises from two overlapping atom laser beams extracted from a Rubidium Bose-Einstein condensate. Our detector is a high-finesse optical cavity which realizes the quantum measurement of the presence of an atom and there

Asantha Cooray

The cosmic 21-cm background frequency spectrum related to the spin-flip transition of neutral Hydrogen present during and before the era of reionization is rich in features associated with physical processes that govern transitions between the two spin states. The intervening electrons in foreground galaxy clusters inversely Compton scatter the 21-cm backgro

Daniel S. Freed, Michael J. Hopkins, Constantin Teleman

This is the second in a series of papers investigating the relationship between the twisted equivariant K-theory of a compact Lie group G and the &#34;Verlinde ring&#34; of its loop group. We introduce the Dirac family of Fredholm operators associated to a positive energy representation of a loop group. It determines a map from isomorphism classes of represe

Huaiyu Duan, George M. Fuller, Yong-Zhong Qian

We examine coherent active-active channel neutrino flavor evolution in environments where neutrino-neutrino forward scattering can engender large-scale collective flavor transformation. We point out a key quantity, the &#34;total effective energy&#34;, which is conserved in several important regimes. Using this concept, we analyze collective neutrino and ant

Benjamin I. Zwiebel

We begin a study of higher-loop corrections to the dilatation generator of N=4 SYM in non-compact sectors. In these sectors, the dilatation generator contains infinitely many interactions, and therefore one expects very complicated higher-loop corrections. Remarkably, we find a short and simple expression for the two-loop dilatation generator. Our solution f

Sergey Morozov, Semjon Vugalter

We consider the Brown--Ravenhall model of a relativistic atom with N electrons and a nucleus of charge Z and prove the existence of an infinite number of discrete eigenvalues for N <= Z. As an intermediate result we prove a HVZ-type theorem for these systems.

V. D&#39; Alessio, L. Piro, E. M. Rossi

We study the spectrum of the prompt emission and the X-ray and optical afterglow fluxes of 54 X-Ray Rich Gamma Ray Burst (XRRs) and X-Ray Flashes (XRFs), observed by BeppoSax and HETE-2. A comparison is then performed with classical Gamma Ray Bursts (GRBs). The goal of this paper is to investigate the nature of XRRs/XRFs, as high redshift GRBs or off-axis GR

Jian Wang, Quan Zhang, Chao-jing Tang

Most of the quantum secure direct communication protocol needs a pre-established secure quantum channel. Only after insuring the security of quantum channel, could the sender encode the secret message and send them to the receiver through the secure channel. In this paper, we present a quantum secure direct communication protocol using Einstein-Podolsky-Rose

C. G. Beneventano, E. M. Santangelo

We study the finite temperature free energy and fermion number for Dirac fields in a one-dimensional spatial segment, under local boundary conditions compatible with the presence of a spectral asymmetry. We discuss in detail the contribution of this part of the spectrum to the determinant. We evaluate the finite temperature properties of the theory for arbit

R. Silva

We rediscuss recent derivations of kinetic equations based on the Kaniadakis&#39; entropy concept. Our primary objective here is to derive a kinetical version of the second law of thermodynamycs in such a $κ$-framework. To this end, we assume a slight modification of the molecular chaos hypothesis. For the $H_κ$-theorem, it is shown that the collisional equi

Peter Constantin, Boris Levant, Edriss S. Titi

In this paper we study analytically the viscous `sabra&#39; shell model of energy turbulent cascade. We prove the global regularity of solutions and show that the shell model has finitely many asymptotic degrees of freedom, specifically: a finite dimensional global attractor and globally invariant inertial manifolds. Moreover, we establish the existence of e

Marek Szydlowski, Wlodzimierz Godlowski

The recent astronomical measurements of distant supernovae as well as other observations indicate that our universe is presently accelerating. There are different proposals for the explanation of this acceleration, such as the cosmological constant $Λ$, decaying vacuum energy, an evolving scalar field (quintessence), phantom energy, etc. Most of these propos

Oliver J. Rosten

The immense freedom in the construction of Exact Renormalization Groups means that the many non-universal details of the formalism need never be exactly specified, instead satisfying only general constraints. In the context of a manifestly gauge invariant Exact Renormalization Group for SU(N) Yang-Mills, we outline a proof that, to all orders in perturbation

Martin E. Olsson

We investigate the thermodynamics of the RR charged two-dimensional type-0A black hole background at finite temperature, and compare with known 0A matrix model results. It has been claimed that there is a disagreement for the free energy between the spacetime and the dual matrix model. Here we find that this discrepancy is sensitive to how the cutoff is impl

Junji Hisano, Shigeki Matsumoto, Osamu Saito, Masato Senami

The lightest neutralino is a viable dark matter (DM) candidate. In this paper we study indirect detection of the wino-like neutralino DM using positrons and antiprotons from the annihilation in the galactic halo. When the mass is around 2 TeV, which is favored from the thermal relic abundance, the non-perturbation effect significantly enhances the annihilati

Matthias Schuett

We classify newforms with rational Fourier coefficients and complex multiplication for fixed weight up to twisting. Under the extended Riemann hypothesis for odd real Dirichlet characters, these newforms are finite in number. We produce tables for weights 3 and 4, where finiteness holds unconditionally.

J. Koplik, T. S. Lo, M. Rauscher, S. Dietrich

We investigate the flow of a nano-scale incompressible ridge of low-volatility liquid along a &#34;chemical channel&#34;: a long, straight, and completely wetting stripe embedded in a planar substrate, and sandwiched between two extended less wetting solid regions. Molecular dynamics simulations, a simple long-wavelength approximation, and a full stability a

Bo Berndtsson

Let $L$ be a (semi)-positive line bundle over a Kahler manifold, $X$, fibered over a complex manifold $Y$. Assuming the fibers are compact and non-singular we prove that the hermitian vector bundle $E$ over $Y$ whose fibers over points $y$ are the spaces of global sections over $X_y$ to $L\gr K_{X/Y}$ endowed with the $L^2$-metric is (semi)-positive in the s

David Berenstein, Diego H. Correa

We study BPS states in a marginal deformation of super Yang-Mills on R x S^3 using a quantum mechanical system of q-commuting matrices. We focus mainly on the case where the parameter q is a root of unity, so that the AdS dual of the field theory can be associated to an orbifold of AdS_5x S^5. We show that in the large N limit, BPS states are described by de

Ola Wessely, Bjorn Skubic, Lars Nordstrom

A mechanism is proposed for manipulating the magnetic state of a helical spin density wave using a current. In this paper, we show that a current through a bulk system with a helical spin density wave induces a spin transfer torque, giving rise to a rotation of the order parameter.The use of spin transfer torque to manipulate the magnetization in bulk system

The LEP Collaboration, ALEPH Collaboration, DELPHI Collaboration, L3 Collaboration

This note presents a combination of published and preliminary electroweak results from the four LEP collaborations ALEPH, DELPHI, L3 and OPAL based on electron-positron collision data taken at centre-of-mass energies above the Z-pole, $130 \GeV$ to $209 \GeV$ (\LEPII), as prepared for the 2005 summer conferences. Averages are derived for di-fermion cross sec

Paola Gori-Giorgi, Andreas Savin

The combination of density functional theory with other approaches to the many-electron problem through the separation of the electron-electron interaction into a short-range and a long-range contribution is a promising method, which is raising more and more interest in recent years. In this work some properties of the corresponding correlation energy functi

Naoyuki Haba, Koichi Yoshioka

Discrete flavor symmetry is explored for an intrinsic property of mass matrix forms of quarks and leptons. In this paper we investigate the S3 permutation symmetry and derive the general forms of mass matrices in various types of S3 theories. We also exhibit particular realizations of previous ansatze of mass matrices, which have often been applied in the li

Dafne Guetta, Tsvi Piran

We compare the luminosity function and rate inferred from the BATSE short hard bursts (SHBs) peak flux distribution with the redshift and luminosity distributions of SHBs observed by Swift/HETE II. While the Swift/HETE II SHB sample is incompatible with SHB population that follows the star formation rate, it is compatible with a SHB rate that reflect a distr

Sin Kyu Kang, C. S. Kim

We propose a scenario that the mass splitting between the first generation of the heavy Majorana neutrino and the other two generations of degenerate heavy neutrinos in the seesaw framework is responsible for the deviation of the solar mixing angle from the maximal mixing, while keeping the maximal mixing between the tau and muon neutrinos as it is. On top o

Yasunari Kurita, Ken-ichi Nakao

In this paper, we study the gravitational collapse of null dust in the cylindrically symmetric spacetime. The naked singularity necessarily forms at the symmetry axis. We consider the situation in which null dust is emitted again from the naked singularity formed by the collapsed null dust and investigate the back-reaction by this emission for the naked sing

Simon J. Devitt, Andrew D. Greentree, Lloyd C. L. Hollenberg

Efficient generation of spatially delocalised entangled states is at the heart of quantum information science. Generally flying qubits are proposed for long range entangling interactions, however here we introduce a bus-mediated alternative for this task. Our scheme permits efficient and flexible generation of deterministic two-qubit operator measurements an

Satoshi Fujimoto

We explore low temperature properties of quantum triangular Heisenberg antiferromagnets in two dimension in the vicinity of the quantum phase transition at zero temperature. Using the effective field theory described by the $SO(3)\times SO(2)/SO(2)$ matrix Ginzburg-Landau-Wilson model and the non-perturbative renormalization group method, we clarify how quan

C. Z. Yuan, P. Wang, X. H. Mo

It is suggested that the newly observed Y(4260) by BARBAR collaboration is a molecular state composed of an omega and a chi_{c1}. Both the production and decay properties are discussed. A consequence for this molecular state, Y(4260), is that it decays into pi+pi-pi0 chi_{c1} with similar rate to pi+ pi- J/psi. It is also expected that Y(4260) -> pi0 pi0 J/p

Yan Li, Hui Jing, Ming-Sheng Zhan

We propose a feasible scheme to realize the optical entanglement of single-photon-added coherent state (SPACS) and show that, besides the Sanders entangled coherent state, the entangled SPACS also leads to new forms of hybrid entanglement of quantum Fock state and classical coherent state. We probe the essential difference of two types of hybrid entangled st

A. Juste

Ten years after its discovery at the Tevatron collider, we still know little about the top quark. Its large mass suggests it may play a key role in the mechanism of Electroweak Symmetry Breaking (EWSB), or open a window of sensitivity to new physics related to EWSB and preferentially coupled to it. To determine whether this is the case, precision measurement

A. Lazarian, D. Pogosyan

We discuss a new technique for studying astrophysical turbulence that utilizes the statistics of Doppler-broadened spectral lines. The technique relates the power Velocity Coordinate Spectrum (VCS), i.e. the spectrum of fluctuations measured along the velocity axis in Position-Position-Velocity (PPV) data cubes available from observations, to the underlying

Alex G. Dias, V. Pleitez

We show that in any invisible axion model due to the effects of effective non-renormalizable interactions related to an energy scale near the Peccei-Quinn, grand unification or even the Planck scale, active neutrinos necessarily acquire masses in the sub-eV range. Moreover, if sterile neutrinos are also included and if appropriate cyclic $Z_N$ symmetries are

H. Ahmedov, I. H. Duru, A. E. Gumrukcuoglu

Feynman propagator is calculated for the time dependent harmonic oscillator by converting the problem into a free particle motion

D. Banerjee, P. Bandyopadhyay

A quantized fermion can be represented by a scalar particle encircling a magnetic flux line. It has the spinor structure which can be constructed from quantum gates and qubits. We have studied here the role of Berry phase in removing dynamical phase during one qubit rotation of a quantized fermion. The entanglement of two qubit inserting spin-echo to one of

Giorgio Brida, Maria Chekhova, Marco Genovese, Alexander Penin

Accurate calibration of photodetectors both in analog and in photon-counting regime is fundamental for various scientific applications, which range from &#34;traditional&#34; quantum optics to the studies on foundations of quantum mechanics, quantum cryptography, quantum computation, etc. In this paper we systematically study the possibility of the absolute

Alberto Barchielli, Giancarlo Lupieri

Some bounds on the entropic informational quantities related to a quantum continual measurement are obtained and the time dependencies of these quantities are studied.

Swarnali Bandopadhyay, A. M. Jayannavar

We study the nature of tunneling phase time for various quantum mechanical structures such as networks and rings having potential barriers in their arms. We find the generic presence of Hartman effect, with superluminal velocities as a consequence, in these systems. In quantum networks it is possible to control the `super arrival&#39; time in one of the arms

Valerio Scarani, Sofyan Iblisdir, Nicolas Gisin, Antonio Acin

The impossibility of perfectly copying (or cloning) an arbitrary quantum state is one of the basic rules governing the physics of quantum systems. The processes that perform the optimal approximate cloning have been found in many cases. These &#34;quantum cloning machines&#34; are important tools for studying a wide variety of tasks, e.g. state estimation an

G. Juzeliunas, J. Ruseckas, P. Ohberg

We study the influence of two resonant laser beams (to be referred to as the control and probe beams) on the centre of mass motion of ultra-cold atoms characterised by three energy levels of the Lambda-type. The laser beams being in the Electromagnetically Induced Transparency (EIT) configuration drive the atoms to their dark states. We impose the adiabatic

Zhao Wei-Qin

It is proved that when solving Schroedinger equations for radially symmetric potentials the effect of higher dimensions on the radial wave function is equivalent to the effect of higher angular momenta in lower dimensional cases. This result is applied to giving solutions for several radially symmetric potentials in N-dimension.

Miloslav Znojil

Coupled pair of PT-symmetric square wells is studied as a prototype of a quantum system characterized by two manifestly non-Hermitian commuting observables. We demonstrate that there exists a domain of couplings where both the respective sets of eigenvalues (viz., energies and spin projections) remain real and where the model acquires a consistent probabilis

Sang Pyo Kim

Using the time-dependent annihilation and creation operators, the invariant operators, for a free mass and an oscillator, we find the coherent-squeezed state representation of a travelling general Gaussian wave packet with initial expectation values, $x_0$ and $p_0$, of the position and momentum and variances, $Δx_0$ and $Δp_0$. The initial general Gaussian

Yury B. Sherkunov

Casimir interaction between two media of ground-state atoms is well described with the help of Lifshitz formula depending upon permittivity of media. We will show that this formula is in contradiction with experimental evidence for excited atoms. We calculate Casimir force between two atoms if one of them or both atoms are excited. We use methods of quantum

Sergey G. Porsev, Andrei Derevianko

A practical high-accuracy relativistic method of atomic structure calculations for univalent atoms is presented. The method is rooted in the coupled-cluster formalism and includes non-perturbative treatment of single and double excitations from the core and single, double and triple excitations involving valence electron. Triple excitations of core electrons