March 2006 arXiv papers — page 18

Faouzi Chaabane, Ahmed Kebaier

We develop a general approach of the almost sure central limit theorem for the quasi-continuous vectorial martingales and we release a quadratic extension of this theorem while specifying speeds of convergence. As an application of this result we study the problem of estimate the variance of a process with stationary and idependent increments in statistics.

Henry de Thelin

We give a construction of measures with partial sum of Lyapunov exponents bounded by below.

M. R. Buneci, P. Stachura

The purpose of this paper is extend the notion of morphism of groupoids introduced by Zakrzewski to locally compact $σ$-compact groupoids endowed with Haar systems and to use the extension to construct a covariant functor from this category to a category of $C^{\ast}$-algebras in the sense of Woronowicz.

Sadek Gala

This paper was withdrawn by arXiv admin because it plagiarizes "Chen, Wen Gu(PRC-BIAP); Lu, Shan Zhen(PRC-BJN) The commutators of fractional integrals on Besov spaces. Acta Math. Sin. (Engl. Ser.) 20 (2004), no. 3, 405--414."

S. Gala, A. Lahmar-Benbernou

This paper was withdrawn by arXiv admin because it plagiarizes "Jiahong Wu The two-dimensional quasi-geostrophic equation with critical or supercritical dissipation 2005 Nonlinearity 18 139-154."

Sadek Gala

This paper was removed by arXiv admin because it plagiarizes "Kozono, Hideo; Shimada, Yukihiro Bilinear estimates in homogeneous Triebel-Lizorkin spaces and the Navier-Stokes equations. Math. Nachr. 276 (2004), 63--74."

Sadek gala

This paper was removed by arXiv admin because it plagiarizes "Ding, Yong(PRC-BJN); Fan, Dashan(PRC-ANH); Pan, Yibiao(1-PITT) Weighted boundedness for a class of rough Marcinkiewicz integrals. Indiana Univ. Math. J. 48 (1999), no. 3, 1037--1055."

Sadek Gala

This paper was removed by arXiv admin because it plagiarizes "Ding, Yong(PRC-BJN); Fan, Dashan(PRC-ANH); Pan, Yibiao(1-PITT) Weighted boundedness for a class of rough Marcinkiewicz integrals. Indiana Univ. Math. J. 48 (1999), no. 3, 1037--1055."

Sadek Gala

This paper was removed by arXiv admin because it plagiarizes the electronic article HYKE 2005-010 (http://www.hyke.org/preprint/index.php), by Jose-A. Carrillo and Lucas C.f. Ferreira, entitled "Self-similar solutions and large time asymptotics for the dissipative quasi-geostrophic equations".

Ben Weinkove

The J-flow is a parabolic flow on Kahler manifolds. It was defined by Donaldson in the setting of moment maps and by Chen as the gradient flow of the J-functional appearing in his formula for the Mabuchi energy. It is shown here that under a certain condition on the initial data, the J-flow converges to a critical metric. This is a generalization to higher d

Oleg Andreev

We make an estimate of the quadratic correction based on gauge/string duality. Like in QCD, it proves to be negative and proportional to the string tension.

Martin Land

In this paper, we examine the Dirac monopole in the framework of Off-Shell Electromagnetism, the five dimensional U(1) gauge theory associated with Stueckelberg-Schrodinger relativistic quantum theory. After reviewing the Dirac model in four dimensions, we show that the structure of the five dimensional theory prevents a natural generalization of the Dirac m

M. A. L. Capri, D. Dudal, J. A. Gracey, V. E. R. Lemes

We report on some recent analytical results on the behaviour of the gluon and ghost propagators in Euclidean SU(2) Yang-Mills theory quantized in the maximal Abelian gauge (MAG). This gauge is of particular interest for the dual superconductivity picture to explain color confinement. Two kinds of effects are taken into account: those arising from a treatment

Leszek Hadasz, Zbigniew Jaskolski

The semiclassical limit of the FZZT Liouville theory on the upper half plane with bulk operators of arbitrary type and with elliptic boundary operators is analyzed. We prove the Polyakov conjecture for an appropriate classical Liouville action. This action is calculated in a number of cases: one bulk operator of arbitrary type, one bulk and one boundary, and

Jean-Paul Blaizot, Ramon Mendez-Galain, Nicolas Wschebor

In a companion paper (hep-th/0512317), we have presented an approximation scheme to solve the Non Perturbative Renormalization Group equations that allows the calculation of the $n$-point functions for arbitrary values of the external momenta. The method was applied in its leading order to the calculation of the self-energy of the O($N$) model in the critica

Hassan Firouzjahi, Louis Leblond, S. -H. Henry Tye

We find the tension spectrum of the bound states of p fundamental strings and q D-strings at the bottom of a warped deformed conifold. We show that it can be obtained from a D3-brane wrapping a 2-cycle that is stabilized by both electric and magnetic fluxes. Because the F-strings are Z_M-charged with non-zero binding energy, binding can take place even if (p

A. F. Kleppe, Chris Wainwright

In many mathematical and physical contexts spinors are treated as Grassmann odd valued fields. We show that it is possible to extend the classification of reality conditions on such spinors by a new type of Majorana condition. In order to define this graded Majorana condition we make use of pseudo-conjugation, a rather unfamiliar extension of complex conjuga

Jonathan Rocher

In the framework of Supersymmetric Grand Unified Theories (SUSY GUTs), the universe undergoes a cascade of symmetry breakings, during which topological defects can be formed. We address the question of the probability of cosmic string formation after a phase of hybrid inflation within a large number of models of SUSY GUTs in agreement with particle and cosmo

Sascha Bornhauser, Manuel Drees

The origin of the most energetic cosmic ray events, with $E \gsim 10^{20}$ eV, remains mysterious. One possibility is that they are produced in the decay of very massive, long--lived particles. It has been suggested that these so--called ``top--down scenarios'' can be tested by searching for ultrarelativistic neutralinos, which would be produced copi

Ikaros I. Bigi, George Chiladze, Gela Devidze, Christoph Hanhart

This paper addresses the role of Large Extra Dimensions in some flavor changing neutral current (FCNC) driven processes. In particular we have investigated radiative decays of charged leptons within models with only one universal extra dimension (UED). Loop contributions with internal fermions and scalars of comparable mass would seem to yield sizeable ampli

R. Plaga

It is shown that if - and only if - ``parallel universes'' exist, an electroweak vacuum that is expected to have decayed since the big bang with a high probability might exist. It would neither necessarily render our existence unlikely nor could it be observed. In this special case the observation of certain combinations of Higgs-boson and top-quark

Giovanni Ossola

We present OPE predictions for the hadronic mass and q^2 moments in inclusive semileptonic charmless B decays, with a lower cut on the charged lepton energy and an upper cut on the hadronic invariant mass. We include non-perturbative corrections through O(1/m_b^3) and perturbative contributions through O(alpha_s^2 beta_0). We also investigate the range of th

A. Bhattacharya, S. N. Banerjee, B. Chakraborti, S. Banerjee

The structure function of the proton has been investigated and has been found to possess the power law behaviour in conformity with the empirical fits to the experimental findings. We have estimated F$_{2}$(x, Q$^{2}$)/F$_{2}$(x, Q$_{0}$$^{2}$) with the anomalous dimension D$_{A}$ predicted from the statistical model as an input and the result is found to be

K. J. Eskola, H. Paukkunen

By studying the Paschos-Wolfenstein (PW) ratio of deep inelastic $ν{\rm Fe}$ and $\bar ν{\rm Fe}$ scattering cross sections, we show that it should be possible to explain the NuTeV $\sin ^2 θ_{\rm W}$ anomaly with quite conventional physics, by introducing mutually different nuclear modifications for the valence-$u$ and valence-$d$ quark distributions of the

A. Bashir, A. Raya

Gauge theories have been a cornerstone of the description of the world at the level of the fundamental particles. The Lagrangian or the action describing the corresponding interactions is invariant under certain gauge transformations. This symmetry is reflected in terms of the Ward-Green-Takahashi (or the Slavnov-Taylor) identities which relate various Green

J. B. Kogut, D. K. Sinclair

Born-Infeld non-linear electrodynamics arises naturally as a field theory description of the dynamics of strings and branes. Most analyses of this theory have been limited to studying it as a classical field theory. We quantize this theory on a Euclidean 4-dimensional space-time lattice and determine its properties using Monte-Carlo simulations. The electrom

Joerg Gayler

A summary of experimental contributions to HSQCD 2005 is given. This includes results from the four HERA experiments H1, ZEUS, HERMES and HERA-B, as well as results from the Tevatron (D0), the CERN hyperon beam (WA98), from RHIC (PHENIX), and IHEP (SVD). I present a short survey of the points appearing most relevant to me.

KLOE collaboration

We present a measurement of the branching ratio of the CP violating decay KL->pi+pi- performed by the KLOE experiment at the phi factory DAFNE. We use 328 pb-1 of data collected in 2001 and 2002, corresponding to ~ 150 million tagged KL mesons. We find BR(KL->pi+pi-) = $(1.963 +/- 0.012 +/- 0.017)x 10^-3. This branching ratio measurement is fully inclusive o

Alexey V. Toporensky

A transient chaos in a closed FRW cosmological model with a scalar field is studied. We describe two different chaotic regimes and show that the type of chaos in this model depends on the scalar field potential. We have found also that for sufficiently steep potentials or for potentials with large cosmological constant the chaotic behavior disappears.

Wayne Eberly, Mark Giesbrecht, Pascal Giorgi, Arne Storjohann

We propose a new algorithm to solve sparse linear systems of equations over the integers. This algorithm is based on a $p$-adic lifting technique combined with the use of block matrices with structured blocks. It achieves a sub-cubic complexity in terms of machine operations subject to a conjecture on the effectiveness of certain sparse projections. A LinBox

D. O. Demchenko, Amy Y. Liu

The electronic and magnetic properties of Fe/GaAs(001) magnetic junctions are investigated using first-principles density-functional calculations. Abrupt and intermixed interfaces are considered, and the dependence of charge transfer, magnetization profiles, Schottky barrier heights, and spin polarization of densities of states on interface structure is stud

D. O. Demchenko, Lin-Wang Wang

We study the structure of the energy spectra along with the character of the states participating in optical transitions in colloidal CdS quantum dots (QDs) using the {\sl ab initio} accuracy charge patching method combined with the %pseudopotential based folded spectrum calculations of electronic structure of thousand-atom nanostructures. In particular, att

A. G. Cunha Netto, C. J. Silva, A. A. Caparica, R. Dickman

Monte Carlo simulations using Wang-Landau sampling are performed to study three-dimensional chains of homopolymers on a lattice. We confirm the accuracy of the method by calculating the thermodynamic properties of this system. Our results are in good agreement with those obtained using Metropolis importance sampling. This algorithm enables one to accurately

Wei Zhang, C. A. R. Sa de Melo

We discuss matter wave interference of Fermi condensates in strongly coupled s-wave and p-wave channels and the time evolution of a single cloud upon release from trap. In s-wave systems, where the order parameter is a complex scalar, we find that the interference patterns depend on the relative phase of the order parameters of the condensates. In p-wave sys

Sang-Hyuk Lee, David G. Grier

A single colloidal sphere circulating around a periodically modulated optical vortex trap can enter a dynamical state in which it intermittently alternates between freely running around the ring-like optical vortex and becoming trapped in local potential energy minima. Velocity fluctuations in this randomly switching state still are characterized by a linear

F. Giazotto, F. Taddei, Rosario Fazio, F. Beltram

A hybrid ferromagnet-superconductor spin valve is proposed. Its operation relies on the interplay between nonequilibrium transport and proximity-induced exchange coupling in superconductors. Huge tunnel magnetoresistance values as large as some 10^6% can be achieved in suitable ferromagnet-superconductor combinations under proper voltage biasing. The control

A. Delisle, D. J. Goznalez, M. J. Stott

The static and dynamic properties of liquid Si at high-pressure have been studied using the orbital free ab-initio molecular dynamics method. Four thermodynamic states at pressures 4, 8, 14 and 23 GPa are considered. The calculated static structure shows qualitative agreement with the available experimental data. We analize the remarkable structural changes

Y. -F. Yang, K. Held

A realistic modeling of manganites should include the Coulomb repulsion between $e_g$ electrons, the Hund's rule coupling to $t_{2g}$ spins, and Jahn-Teller phonons. Solving such a model by dynamical mean field theory, we report large magnetoresistances and spectra in good agreement with experiments. The physics of the unusual, insulating-like paramagnet

I. Vilfan

The properties of Mo_6S_6 nanowires were investigated with ab-initio calculations based on the density-functional theory. The molecules build weakly coupled one-dimensional chains, like Mo_6Se_6 and Mo_6S_(9-x)I_x, and the crystals are strongly uniaxial in their mechanical and electronic properties. The calculated moduli of elasticity and resilience along th

Th. von Hofe, J. Kroeger, R. Berndt

Using scanning tunneling microscopy at low temperatures we investigated the adsorbate system Cu(111)-Cs for various cesium coverages. At low coverages we observe a hexagonally ordered Cs adsorption layer with a mutual adsorbate distance of 1.1 nm. This distance is discussed in terms of a commensurate adsorption superstructure which is stabilized by long-rang

Sumiyoshi Abe, Yutaka Nakada

The Tsallis entropy, which is a generalization of the Boltzmann-Gibbs entropy, plays a central role in nonextensive statistical mechanics of complex systems. A lot of efforts have recently been made on establishing a dynamical foundation for the Tsallis entropy. They are primarily concerned with nonlinear dynamical systems at the edge of chaos. Here, it is s

A. Golub

We examine the statistics of current fluctuations in a junction with a quantum dot described by Kondo Hamiltonian. With the help of Keldysh technique we calculate shot noise as a function of applied voltage at zero temperature using the fix-point Hamiltonian. These calculations are complementary to similar ones performed earlier in the mean field slave boson

A. Liebsch, T. A. Costi

The two-band Hubbard model involving subbands of different widths is investigated via finite-temperature exact diagonalization (ED) and dynamical mean field theory (DMFT). In contrast to the quantum Monte Carlo (QMC) method which at low temperatures includes only Ising-like exchange interactions to avoid sign problems, ED permits a treatment of Hund's ex

Hyun-Tak Kim, Byung-Gyu Chae, Bong-Jun Kim, Yong-Wook Lee

A strongly correlated Mott first-order metal-insulator transition (MIT) (or Jump) not accompanied by the structural phase transition (SPT) was clearly revealed in VO_2, (New J. Phys. 6 (1004) 52, Appl. Phys. Lett. 86 (2005) 242101, Physica B 369 (2005) 76). In order to re-confirm the MIT for a VO_2-based device with a narrow width of 3 micrmeter and a length

Sujit Sarkar

We study the dimerized spin ladder with nearest-neighbor ($J_1$) and next-nearest-neighbor ($J_2$) anti-ferromagnetic interaction under a magnetic field. We predict the existence of different magnetization plateaus for the presence of spin-Peierls interaction on both $J_1$ and $J_2$. Magnetization plateau at $m=0$ for $J_1$ dimerization is spontaneous due to

C. S. Tang, C. S. Chu

We consider a nonadiabatic quantum pumping phenomena in a ballistic narrow constriction. The pumping is induced by a potential that has both spatial and temporal periodicity characterized by $K$ and $Ω$. In the zero frequency ($Ω=0$) limit, the transmission through narrow constriction exhibits valley structures due to the opening up of energy gaps in the pum

F Alonso-Marroquin, I. Vardoulakis, H. J. Herrmann, D. Weatherley

Sliding and rolling are two outstanding deformation modes in granular media. The first one induces frictional dissipation whereas the latter one involves deformation with negligible resistance. Using numerical simulations on two-dimensional shear cells, we investigate the effect of the grain rotation on the energy dissipation and the strength of granular mat

K. Van Houcke, S. M. A. Rombouts, L. Pollet

We study the thermodynamics of a small, isolated superconducting grain using a recently developed quantum Monte Carlo method. This method allows us to simulate grains at any finite temperature and with any level spacing in an exact way. We focus on the pairing energy, pairing gap, condensation energy, heat capacity and spin susceptibility to describe the gra

C. S. Tang, C. S. Chu

This work investigates the quantum transport in a narrow constriction acted upon by a finite-range transversely polarized time-dependent electric field. A generalized scattering-matrix method is developed that has incorporated a time-dependent mode-matching scheme. The transverse field induces coherent inelastic scatterings that include both intersubband and

J. S. Kim, R. K. Kremer, L. Boeri, F. S. Razavi

The superconducting state of Ca-intercalated graphite CaC6 has been investigated by specific heat measurements. The characteristic anomaly at the superconducting transition (Tc = 11.4 K) indicates clearly the bulk nature of the superconductivity. The temperature and magnetic field dependence of the electronic specific heat are consistent with a fully-gapped

C. S. Tang, C. S. Chu

The effect of a time-modulated gate-voltage on the differential conductance $G$ of a saddle-point constriction is studied. The constriction is modeled by a symmetric saddle-point potential and the time-modulated gate-voltage is represented by a potential of the form $V_{0} θ(a/2-|x-x_{c}|) \cos (ωt)$. For $\hbarω$ less than half of the transverse subband ene

S. -W. Jung, H. -W. Lee

We demonstrate theoretically that the spin polarization of current can be electrically amplified within nonmagnetic semiconductors by exploiting the fact the spin current, compared to the charge current, is weakly perturbed by electric driving forces. As a specific example, we consider a T-shaped current branching geometry made entirely of a nonmagnetic semi

C. Stock, D. Ellis, I. P. Swainson, Guangyong Xu

Using neutron elastic and inelastic scattering and high-energy x-ray diffraction, we present a comparison of 40% Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$-60% PbTiO$_{3}$ (PMN-60PT) with pure Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$ (PMN) and PbTiO$_{3}$ (PT). We measure the structural properties of PMN-60PT to be identical to pure PT, however, the lattice dynamics are exactly

H. A. Fernandes, E. Arashiro, A. A. Caparica, J. R. Drugowich de Felicio

We have investigated the dynamic critical behavior of the two-dimensional 4-state Potts model using an alternative order parameter first used by Vanderzande [J. Phys. A: Math. Gen. \textbf{20}, L549 (1987)] in the study of the Z(5) model. We have estimated the global persistence exponent $θ_g$ by following the time evolution of the probability $P(t)$ that th

E. Liang

We review recent PIC simulation results which show that double-sided irradiaton of a thin overdense plasma slab by ultra-intense laser pulses from both sides can lead to sustained comoving acceleration of surface electrons to energies much higher than the conventional ponderomotive limit. The acceleration stops only when the electrons drift transversely out

E. Liang, K. Noguchi, S. Sugiyama

We review PIC simulation results of GRB emissions for both the Poynting flux and shock scenarios

Ralph E. Pudritz, Rachid Ouyed, Christian Fendt, Axel Brandenburg

We review advances in the theoretical and computational studies of disk winds, jets and outflows including: the connection between accretion and jets, the launch of jets from magnetized disks, the coupled evolution of jets and disks, the interaction of magnetized young stellar objects with their surrounding disks and the relevance to outflows, and finally, t

L. Christensen, K. Jahnke, L. Wisotzki, S. F. Sanchez

Powerful radio galaxies and radio-loud quasars at high redshifts are frequently associated with extended emission-line regions (EELRs). Here we investigate the [O II] EELR around the quasar 3C 196 at z=0.871 using integral field spectroscopy. We also detect extended [Ne II] emission at a distance of about 30 kpc from the core. The emission is aligned with th

Michael D. Gladders, H. K. C. Yee, Subhabrata Majumdar, L. Felipe Barrientos

[abridged] We present a first cosmological analysis of a refined cluster catalog from the Red-Sequence Cluster Survey (RCS). The input cluster sample is derived from 72.07 square degrees of imaging data [...] The catalog contains 956 clusters over 0.35<z<0.95, limited by cluster richness and richness error. The calibration of the survey images has been exten

K. M. Menten, M. J. Reid, E. Kruegel, M. J. Claussen

We describe Very Large Array observations of the extreme carbon star IRC+10216 at 8.4, 14.9, and 22.5 GHz made over a two year period. We find possible variability correlated with the infrared phase and a cm- to sub-millimeter wavelength spectral index very close to 2. The variability, observed flux densities, and upper limit on the size are consistent with

S. A. Stern, D. C. Slater, J. Scherrer, J. Stone

We describe the design, performance and scientific objectives of the NASA-funded ALICE instrument aboard the ESA Rosetta asteroid flyby/comet rendezvous mission. ALICE is a lightweight, low-power, and low-cost imaging spectrograph optimized for cometary far-ultraviolet (FUV) spectroscopy. It will be the first UV spectrograph to study a comet at close range.

Yuri Levin

We propose a scenario in which massive stars form in a self-gravitating gaseous disc around a supermassive black hole. We find that once the surface density of the disc exceeds a critical value, the disc fragments into dense clumps. The clumps accrete material from the remaining disc and merge into larger clumps; the upper mass of a merged clump is a few ten

Judith G. Cohen, Andrew McWilliam, Stephen Shectman, Ian Thompson

We have carried out a detailed abundance analysis for a sample of 16 carbon stars found among candidate extremely metal-poor (EMP) stars from the Hamburg/ESO Survey. We find that the Fe-metallicities for the cooler C-stars (Teff ~ 5100K) have been underestimated by a factor of ~10 by the standard HES survey tools. The results presented here provided crucial

F. I. Pelupessy, P. P. Papadopoulos, P. P. van der Werf

We present models of the evolution of the gaseous and stellar content of galaxies incorporating the formation of H_2 out of HI gas as part of such a model. We do so by formulating a subgrid model for gas clouds that uses well-known cloud scaling relations and solves for the HI-H_2 balance set by the H_2 formation on dust grains and its FUV-induced photodisso

M. Turler, M. Chernyakova, T. J. -L. Courvoisier, C. Foellmi

Aims. The aim of this work is to identify and study spectral features in the quasar 3C 273 usually blended by its strong jet emission. Method. A historic minimum in the sub-millimetre emission of 3C 273 triggered coordinated multi-wavelength observations in June 2004. X-ray observations from the INTEGRAL, XMM-Newton and RXTE satellites are complemented by gr

Paul C. Clark, Ian A. Bonnell

In this paper, we examine whether clumpy, colliding, flows could be responsible for the clump mass functions that have been observed in several regions of embedded star formation, which have been shown to be described by a Salpeter type slope. The flows presented here, which comprise a population of initially identical clumps and the calculations are perform

Gustavo A. Lanfranchi, Francesca Matteucci, Gabriele Cescutti

In order to verify the effects of the most recent data on the evolution of Carina and Sagittarius Dwarf Spheroidal Galaxies (dSph) and to set tight constraints on the main parameters of chemical evolution models, we study in detail the chemical evolution of these galaxies through comparisons between the new data and the predictions of a model, already tested

F. Schuller, A. Omont, I. S. Glass, M. Schultheis

Context: The stellar populations in the central region of the Galaxy are poorly known because of the high visual extinction and very great source density in this direction. Aims: To use recent infrared surveys for studying the dusty stellar objects in this region. Methods: We analyse the content of a 20x20 arcmin^2 field centred at (l,b)=(-0.27,-0.06) observ

Aigen Li, K. A. Misselt, Y. J. Wang

The dust in the Small Magellanic Cloud (SMC), an ideal analog of primordial galaxies at high redshifts, differs markedly from that in the Milky Way by exhibiting a steeply rising far-ultraviolet extinction curve, an absence of the 2175 Angstrom extinction feature, and a local minimum at ~12 micron in its infrared emission spectrum, suggesting the lack of ult

Jose Gaite

&#34;Cut-out sets&#34; are fractals that can be obtained by removing a sequence of disjoint regions from an initial region of d-dimensional euclidean space. Conversely, a description of some fractals in terms of their void complementary set is possible. The essential property of a sequence of fractal voids is that their sizes decrease as a power law, that is

M. Arnould, S. Goriely, G. Meynet

It has been speculated that WR winds may have contaminated the forming solar system, in particular with short-lived radionuclides (half-lives in the approximate 10^5 - 10^8 y range) that are responsible for a class of isotopic anomalies found in some meteoritic materials. We revisit the capability of the WR winds to eject these radionuclides using new models

Y. Becherini

The ANTARES Collaboration is building an underwater neutrino telescope in the Mediterranean sea. The telescope is designed to search for high energy (E $>1$ TeV) galactic and extra-galactic neutrino sources, but could also be sensitive to neutrinos originating from the decay of neutralino and exotic particles. The detector is a 3-dimensional array of photomu

D. Lomiashvili, G. Machabeli, I. Malov

It is shown that the drift waves near the light cylinder can cause the modulation of the emission with periods of the order several seconds. These periods explain the intervals between successive pulses observed in &#34;magnetars&#34; and radio pulsars with long periods. The model under consideration makes it possible to calculate the real rotation periods o

C. Vastel, P. Caselli, C. Ceccarelli, T. G. Phillips

Prestellar cores are unique laboratories for studies of the chemical and physical conditions preceding star formation. We observed the prestellar core L1544 in the fundamental transition of ortho-H2D+ (1_1,0-1_1,1) at different positions over 100&#34;, and found a strong correlation between its abundance and the CO depletion factor. We also present a tentati

E. Roediger, M. Brueggen, M. Hoeft

Spiral galaxies that move through the intracluster medium lose a substantial amount of their gas discs due to ram pressure stripping. The recent observations of NGC 4388 by Oosterloo & van Gorkom 2005 reveal a tail of stripped gas of ~ 100 kpc behind the source galaxy. We present first 3D hydrodynamical simulations of the evolution of such ram pressure strip

M. Puech, H. Flores, F. Hammer, M. D. Lehnert

We used the moderately high spectral resolution of FLAMES/GIRAFFE (R=10000) to derive electron densities from [OII] line ratios in 6 galaxies at z~0.55. These measurements have been done through the GIRAFFE multiple integral field units and are the very first mapping of electron densities in such distant objects. This allows us to confirm an outflow and iden

H. Flores, F. Hammer, M. Puech, P. Amram

A precise derivation of the evolution of the Tully Fisher is crucial to understand the interplay between dark matter and baryonic matter in cosmological models, Using 15 deployable integral field units of FLAMES/GIRAFFE at VLT, we have recovered the velocity fields of 35 galaxies at intermediate redshift (0.4 < z < 0.75). This facility is able to recover the

M. Puech, F. Hammer, H. Flores, G. Ostlin

Luminous Compact Galaxies are enigmatic sources by many aspects. They can reach the luminosity of the Milky Way within a radius of only a few kpc. They also represent one of the most rapidly evolving populations of galaxies since they represent up to 1/5 of the luminous galaxies at redshift z= 0.7 while being almost absent in the local Universe. The measurem

K. Pavlovski, G. Burki, P. Mimica

Light curves of the long-period Algols are known for their complex shape (asymmetry in the eclipse, light variations outside eclipse, changes from cycle-to-cycle), and their interpretation is not possible in the standard model of binary stars. Complex structures present in these active Algol systems could be studied with the eclipse-mapping method which was

M. G. Hoare, S. E. Kurtz, S. Lizano, E. Keto

We review the phenomenon of ultra-compact H II regions (UCHIIs) as a key phase in the early lives of massive stars. This most visible manifestation of massive star formation begins when the Lyman continuum output from the massive young stellar object becomes sufficient to ionize the surroundings from which it was born. Knowledge of this environment is gained

N. M. Forster Schreiber, R. Genzel, M. D. Lehnert, N. Bouche

We present 0.5&#34; resolution near-IR integral field spectroscopy of the Ha line emission of 14 z~2 UV-selected BM/BX galaxies obtained with SINFONI at ESO/VLT. The mean Ha half-light radius r_1/2 is about 4kpc and line emission is detected over > ~20kpc in several sources. In 9 sources, we detect spatially-resolved velocity gradients, from 40 to 410 km/s o

P. Battinelli, S. Demers, W. E. Kunkel

We have previously established, from a carbon star survey, that the Local Group dwarf irregular galaxy NGC 6822 is much larger than its central bright core. Four MegaCam fields are acquired to survey a 2$^\circ\times$ 2$^\circ$ area centred on NGC 6822 to fully determine its extent and map its stellar populations. Photometry of over one million stars is obta

Megan E. Eckart, Daniel Stern, David J. Helfand, Fiona A. Harrison

We present the catalog of 477 spectra from the Serendipitous Extragalactic X-ray Source Identification (SEXSI) program, a survey designed to probe the dominant contributors to the 2-10 keV cosmic X-ray background. Our survey covers 1 deg^2 of sky to 2-10 keV fluxes of 10^-14 erg cm^-2 s^-1, and 2 deg^2 for fluxes of 3 x 10^-14 erg cm^-2 s^-1. Our spectra rea

Liu Xiang, Cormac Reynolds, Richard Strom, Daniele Dallacasa

We present the results of EVN polarization observations of fourteen GHz-Peaked-Spectrum (GPS) radio sources at 5 GHz. These sources were selected from bright GPS source samples and we aimed at finding Compact Symmetric Objects (CSOs). We have obtained full polarization 5 GHz VLBI observations of 14 sources providing information on their source structure and

Rafael Millan-Gabet, Fabien Malbet, Rachel Akeson, Christoph Leinert

We review recent advances in our understanding of the innermost regions of the circumstellar environment around young stars, made possible by the technique of long baseline interferometry at infrared wavelengths. Near-infrared observations directly probe the location of the hottest dust. The characteristic sizes found are much larger than previously thought,

Michael Politano, Kevin P. Weiler

The distribution of secondary star masses in present-day post-common envelope binaries (PCEBs) is calculated using four different models for angular momentum loss (AML) during the post-CE phase: only gravitational radiation (GR), GR + disrupted magnetic braking (DMB), GR + reduced MB, and GR + intermediate MB. For the DMB model, we find that the number of PC

Jes K. Jorgensen, Paul M. Harvey, Neal J. Evans, Tracy L. Huard

We present observations of 3.86 sq. deg. of the Perseus molecular cloud complex with the Spitzer Space Telescope Infrared Array Camera (IRAC). The maps show strong extended emission arising from shocked H2 in outflows in the region and from polycyclic aromatic hydrocarbon features. More than 120,000 sources are extracted toward the cloud. Based on their IRAC

Zoltan Haiman, Greg L. Bryan

The primordial gas in the earliest dark matter halos, collapsing at redshifts around z=20, with masses M_halo=10^6 M_sun, and virial temperatures T_vir<10^4K, relied on the presence of molecules for cooling. Several theoretical studies have suggested that gas contraction and star-formation in these minihalos was suppressed by radiative, chemical, thermal, an

Pak Yuen Chan, Nigel Goldenfeld, Myron Salamon

From a heuristic calculation of the leading order essential singularity in the distribution of Yang-Lee zeroes, we obtain new scaling relations near the ferromagnetic-Griffiths transition, including the prediction of a discontinuity on the analogue of the critical isotherm. We show that experimental data for the magnetization and heat capacity of $\mathrm{La

Heather Knutson, David Charbonneau, Robert W. Noyes, Timothy M. Brown

We use multi-band photometry to refine estimates for the planetary radius and orbital inclination of the transiting planet system HD 209458. We gathered 1066 spectra over four distinct transits with the STIS spectrometer on the Hubble Space Telescope using two gratings with a resolution R=1500 and a combined wavelength range of 290-1030 nm. We divide the spe

Alison Demaria, Catherine I. Low, Raymond R. Volkas

The idea of quark-lepton universality at high energies has recently been explored in unified theories based upon the quartification gauge group SU(3)^4. These schemes encompass a quark-lepton exchange symmetry that results upon the introduction of leptonic colour. It has been demonstrated that in models in which the quartification gauge symmetry is broken do

Zhun Lu, Ivan Schmidt

We present an analysis of the process $e^+e^-\to V^*\toππγ$, where $V=γ$ or $V=Z$ boson, in the kinematical region where $\sqrt{s}$, the c.m. energy of the $e^+e^-$ pair, is large but much below the $Z$-pole. The subprocess $V^*\to ππγ$ can be described by the convolution of the hard scattering coefficient $V\to q \bar{q} γ$ and the general distribution ampl

Max Chaves, Douglas Singleton

We construct a model of phantom energy using the graded Lie algebra SU(2/1). The negative kinetic energy of the phantom field emerges naturally from the graded Lie algebra, resulting in an equation of state with w<-1. The model also contains ordinary scalar fields and anti-commuting (Grassmann) vector fields which can be taken as two component dark matter. A

Lan Wang, Cheng Li, Guinevere Kauffmann, Gabriella De Lucia

We use the Millennium Simulation, a 10 billion particle simulation of the growth of cosmic structure, to construct a new model of galaxy clustering. We adopt a methodology that falls midway between the traditional semi-analytic approach and the halo occupation distribution(HOD) approach. In our model, we adopt the positions and velocities of the galaxies tha

D. V. Ahluwalia-Khalilova

Assuming the validity of the general relativistic description of gravitation on astrophysical and cosmological length scales, we analytically infer that the Friedmann-Robertson-Walker cosmology with Einsteinian cosmological constant, and a vanishing spatial curvature constant, unambiguously requires significant amount of dark matter. This requirement is cons

Joao Magueijo

In quantum gravity theories Planckian behavior is triggered by the energy of {\it elementary} particles approaching the Planck energy, $E_P$, but it&#39;s also possible that anomalous behavior strikes systems of particles with total energy near $E_P$. This is usually perceived to be pathological and has been labelled ``the soccer ball problem&#39;&#39;. We p

B. Aubert

We present measurements of CP-violating asymmetries and branching fractions for the decays omegapi+, omegaK+, and omegaK0. The data sample corresponds to 232 million BBbar pairs produced by e+e- annihilation at the Upsilon(4S) resonance. For the decay omegaKs, we measure the time-dependent CP-violation parameters S=0.51+0.35-0.39+/-0.02, and C=-0.55+0.28-0.2

Ralph M. Kaufmann, R. C. Penner

We introduce a combinatorial model based on measured foliations in surfaces which captures the phenomenology of open/closed string interactions. The predicted equations are derived in this model, and new equations can be discovered as well. In particular, several new equations together with known transformations generate the combinatorial version of open/clo

B. Eden, M. Staudacher

We derive the two-loop Bethe ansatz for the sl(2) twist operator sector of N=4 gauge theory directly from the field theory. We then analyze a recently proposed perturbative asymptotic all-loop Bethe ansatz in the limit of large spacetime spin at large but finite twist, and find a novel all-loop scaling function. This function obeys the Kotikov-Lipatov transc

J. S. Kim, L. Boeri, R. K. Kremer, F. S. Razavi

The pressure effect on the superconducting transition temperature ($T_c$) of the newly-discovered Ca-intercalated graphite compound CaC$_6$ has been investigated up to $\sim$ 16 kbar. $T_c$ is found to increase under pressure with a large relative ratio $Δ$$T_c$/$T_c$ of $\approx$ +0.4 %/kbar. Using first-principles calculations, we show that the large and p