January 2003 arXiv papers — page 3

Firooz Arash

Partonic structure of constituent quark (or{\it{valon}}) in the Next-to-Leading Order is used to calculate pion structure function. This is a further demonstration of the finding that the constituent quark structure is universal, and once it is calculated, the Structure of any hadron can be predicted thereafter, using a convolution method, without introducin

D. Melikhov, O. Nachtmann, T. Paulus

We consider a model with $ρππ$, $ρKK$, and gauge-invariant $ργ$ couplings and obtain the pion form factor $F_π$ at timelike momentum transfers by resummation of pion and kaon loops. We use a dispersion representation for the loop diagrams and analyse ambiguities related to subtraction constants. The resulting representation for $F_π$ is shown to have the for

V. N. Folomeev

The quantum evolution of a model of the universe with account of two scalar fields ({\it dilaton} and {\it inflaton}) is considered. For this case, the closed and flat models has been examined. It is shown that in both cases the realization of conditions necessary for inflation is strongly depends on coupling constant for dilaton and inflaton fields.

J. Ellis, E. Gravanis, N. E. Mavromatos, D. V. Nanopoulos

We extend previous analyses of the violation of Lorentz invariance induced in a non-critical string model of quantum space-time foam, discussing the propagation of low-energy particles through a distribution of non-relativistic D-particles.We argue that nuclear and atomic physics experiments do not constitute sensitive probes of this approach to quantum grav

S. Sivasubramanian, A. Widom, Y. N. Srivastava

The conventional Clausius-Mossotti polarization equation of state is known to be unstable for polar liquids having molecules with high polarizability. Room temperature water is an important example. The instability in the polarization equation of state is of the typical loop form requiring an ``equal area'' construction for studying the stable ordere

K. P. J. Kytölä, E. T. Seppälä, M. J. Alava

The energy of an elastic manifold in a random landscape at T=0 is shown numerically to obey a probability distribution that depends on size of the box it is put into. If the extent of the spatial fluctuations of the manifold is much less than that of the system, a cross-over takes place to the Gumbel-distribution of extreme statistics. If they are comparable

Karsten Reuter, Matthias Scheffler

The phase diagram of surface structures for the model catalyst RuO2(110) in contact with a gas environment of O2 and CO is calculated by density-functional theory and atomistic thermodynamics. Adsorption of the reactants is found to depend crucially on temperature and partial pressures in the gas phase. Assuming that a catalyst surface under steady-state ope

David A. Rabson, John F. Huesman, Benji N. Fisher

Crystallography has proven a rich source of ideas over several centuries. Among the many ways of looking at space groups, N. David Mermin has pioneered the Fourier-space approach. Recently, we have supplemented this approach with methods borrowed from algebraic topology. We now show what topology, which studies global properties of manifolds, has to do with

Z. Crljen, P. Lazic, D. Sokcevic, R. Brako

We have theoretically studied the stability and reconstruction of (111) surfaces of Au, Pt, and Cu. We have calculated the surface energy, surface stress, interatomic force constants, and other relevant quantities by ab initio electronic structure calculations using the density functional theory (DFT), in a slab geometry with periodic boundary conditions. We

J. M. Martin-Olalla, F. J. Romero, S. Ramos, M. C. Gallardo

The asymptotic behaviour near phase transitions can be suitably characterized by the scaling of $Δs/Q^2$ with $ε=1-T/T_c$, where $Δs$ is the excess entropy and $Q$ is the order parameter. As $Δs$ is obtained by integration of the experimental excess specific heat of the transition $Δc$, it displays little experimental noise so that the curve $\log(Δs/Q^2)$ v

F. Rullier-Albenque, H. Alloul, R. Tourbot

Electron irradiation has been used to introduce point defects in a controlled way in the CuO2 planes of underdoped and optimally doped YBCO. This technique allows us to perform very accurate measurements of Tc and of the residual resistivity in a wide range of defect contents xd down to Tc=0. The Tc decrease does not follow the variation expected from pair b

S. V. Demishev, Y. Inagaki, M. M. Markina, H. Ohta

Using high frequency (up to 450 GHz) ESR and low temperature specific heat measurements we find that insertion of 1% Fe and 2% Co damps spin-Peierls and Neel transitions and for T<30K gives rise to onset of a quantum critical behaviour characteristic for a random dimer Griffiths phase.

C. F. Bird, A. J. Fisher, D. R. Bowler

Dangling bond wires on Si(001) are prototypical one dimensional wires, which are expected to show polaronic and solitonic effects. We present electronic structure calculations, using the tight binding model, of solitons in dangling-bond wires, and demonstrate that these defects are stable in even-length wires, although approximately 0.1 eV higher in energy t

Bogdan A. Bernevig, Domenico Giuliano, Robert B. Laughlin

The elementary excitations of strongly correlated one-dimensional electronic systems - spinons and holons - are discussed in an exact solution of the Haldane-Shastry and Kuramoto-Yokoyama model. We derive and exactly solve the equation of motion both for the two-spinon wavefunction and for the one-spinon, one-holon wavefunction. By solving the equations of m

Andrea Montanari, Federico Ricci-Tersenghi

The low-temperature phase of discontinuous mean-field spin glasses is generally described by a one-step replica symmetry breaking (1RSB) Ansatz. The Gardner transition, i.e. a very-low-temperature phase transition to a full replica symmetry breaking (FRSB) phase, is often regarded as an inessential, and somehow exotic phenomenon. In this paper we show that t

Constantino Tsallis, Domingo Prato, Angel R. Plastino

A variety of astronomical phenomena appear to not satisfy the ergodic hypothesis in the relevant stationary state, if any. As such, there is no reason for expecting the applicability of Boltzmann-Gibbs (BG) statistical mechanics. Some of these phenomena appear to follow, instead, nonextensive statistical mechanics. In the same manner that the BG formalism is

Veit Schwämmle, Hans J. Herrmann

Transverse dunes appear in regions of mainly unidirectional wind and high sand availability. A dune model is extended to two dimensional calculation of the shear stress. It is applied to simulate dynamics and morphology of transverse dunes which seem to reach translational invariance and do not stop growing. Hence, simulations of two dimensional dune fields

P. Calabrese, V. Martin-Mayor, A. Pelissetto, E. Vicari

We compute the dynamic structure factor for the Ising model with a purely relaxational dynamics (model A). We perform a perturbative calculation in the $ε$ expansion, at two loops in the high-temperature phase and at one loop in the temperature magnetic-field plane, and a Monte Carlo simulation in the high-temperature phase. We find that the dynamic structur

H. Johannesson, G. I. Japaridze

We study a one-dimensional electron liquid embedded in a 2D antiferromagnetic insulator, and coupled to it via a weak antiferromagnetic spin exchange interaction. We argue that this model may qualitatively capture the physics of a single charge stripe in the cuprates on length- and time scales shorter than those set by its fluctuation dynamics. Using a local

J. C. Lasjaunias, K. Biljakovic, J. L. Sauvajol, P. Monceau

We present the first low-temperature thermodynamic investigation of the controlled physisorption of He$^{4}$ gas in carbon single-wall nanotube (SWNT) samples. The vibrational specific heat measured between 100 mK and 6 K demonstrates an extreme sensitivity to outgassing conditions. For bundles with a few number of NTs the extra contribution to the specific

Bo Liu, Burkhard Duenweg

Within Kirkwood theory, we study the translational diffusion coefficient of a single polymer chain in dilute solution, and focus on the small difference between the short--time Kirkwood value $D^{(K)}$ and the asymptotic long--time value $D$. We calculate this correction term by highly accurate large--scale Brownian Dynamics simulations, and show that it is

G. Tiana, F. Simona, G. M. S. De Mori, R. A. Broglia

The results of minimal model calculations suggest that the stability and the kinetic accessibility of the native state of small globular proteins are controlled by few &#34;hot&#34; sites. By mean of molecular dynamics simulations around the native conformation, which simulate the protein and the surrounding solvent at full--atom level, we generate an energe

Weihong Zheng, J. Oitmaa

Linked cluster series expansions about the Ising limit are used to study ground state preperties, viz. ground state energy, magnetization and excitation spectra, for mixed spin S=(1/2,1) quantum ferrimagnets on simple bipartite lattices in 1, 2, and 3-dimensions. Results are compared to second-order spin wave theory and, in general, excellent agreement is ob

Yong P. Chen, R. M. Lewis, L. W. Engel, D. C. Tsui

We have observed a resonance in the real part of the finite frequency diagonal conductivity using microwave absorption measurements in high quality 2D electron systems near {\em integer fillings}. The resonance exists in some neighborhood of filling factor around corresponding integers and is qualitatively similar to previously observed resonance of weakly p

A. Oosawa, M. Fujisawa, T. Osakabe, K. Kakurai

Neutron elastic scattering measurements have been performed under the hydrostatic pressure in order to investigate the spin structure of the pressure-induced magnetic ordering in the spin gap system TlCuCl$_3$. Below the ordering temperature $T_{\rm N}=16.9$ K for the hydrostatic pressure $P=1.48$ GPa, magnetic Bragg reflections were observed at the reciproc

Sabine Dieluweit, Harald Ibach, Margret Giesen, T. L. Einstein

We have investigated the step stiffness on Cu(001) surfaces as a function of step orientation by two independent methods at several temperatures near 300 K. Both sets of data agree well and show a substantial dependence of the stiffness on the angle of orientation. With the exception of steps oriented along $<110>$, the experimental stiffness is significantl

Sung-Sik Lee, Sung-Ho Suck Salk

Based on our recent holon-pair boson theory of the t-J Hamiltonian (Phys. Rev. B 64, 052501 (2001)) we report the doping dependence of the bose condensation energy, superfluid weight and spectral peak intensity. We find a universality of doping dependence in these physical quantities, by equally showing an arch shape in the variations of their magnitudes wit

S. Verga, A. Knigavko, F. Marsiglio

Recent energy dispersion measurements in several families of the hole-doped copper oxides have revealed a kink in the energy vs. momentum relation. These have tentatively been identified as due to electron phonon coupling. We invert this data directly to determine the bosonic spectral function; the kink gives rise to a singular function in the phonon energy

Boris Kastening

An earlier four-loop calculation of the fluctuation pressure of a fluid membrane between two infinite walls is extended to five loops. Variational perturbation theory is used to extract the hard-wall limit from perturbative results obtained with a smooth potential. Comparison with a structurally similar quantum mechanics problem of a particle in a box is use

M. Bernardi, R. K. Sheth, J. Annis, S. Burles

A sample of nearly 9000 early-type galaxies, in the redshift range 0.01 < z < 0.3, was selected from the Sloan Digital Sky Survey using morphological and spectral criteria. This paper describes how the sample was selected, presents examples of images and seeing corrected fits to the observed surface brightness profiles, describes our method for estimating K-

M. Bernardi, R. K. Sheth, J. Annis, S. Burles

The colors and chemical abundances of early-type galaxies at redshifts z<0.3 are studied using a sample of nearly 9000 galaxies, selected from the Sloan Digital Sky Survey using morphological and spectral criteria. In this sample, redder galaxies have larger velocity dispersions. Color also correlates with magnitude and size, but these correlations are entir

Evan Scannapieco, Raffaella Schneider, Andrea Ferrara

We conduct a comprehensive investigation of the detectability of the first stars and their enrichment signatures in galaxy clusters. We show that the mean metallicity of outflows from objects containing these Population III (PopIII) stars is well above the critical transition metallicity (Z_cr \sim 10^-4) that marks the formation of normal stars. Thus the fr

Jonathan Granot, Pawan Kumar, Tsvi Piran

We investigate how the angular structure of GRB jets effects the afterglow light curves at different viewing angles, $θ_{v}$, from the jet symmetry axis. A numerical hydrodynamical modeling for the evolution of a relativistic collimated outflow, as it interacts with the surrounding medium, is carried out, and compared to two simple models that make opposite

M. Bernardi, R. K. Sheth, J. Annis, S. Burles

A magnitude limited sample of nearly 9000 early-type galaxies, in the redshift range 0.01 < z < 0.3, was selected from the Sloan Digital Sky Survey using morphological and spectral criteria. The Fundamental Plane relation in this sample is R_o ~ sigma^{1.49\pm 0.05} I_o^{-0.75\pm 0.01} in the r* band. It is approximately the same in the g*, i* and z* bands.

Dongsu Ryu, Jongsoo Kim, Seung Soo Hong, T. W. Jones

The Parker instability, which has been considered as a process governing the structure of the interstellar medium, is induced by the buoyancy of magnetic field and cosmic rays. In previous studies, while the magnetic field has been fully incorporated in the context of isothermal magnetohydrodynamics, cosmic rays have been normally treated with the simplifyin

M. Bernardi, R. K. Sheth, J. Annis, S. Burles

A magnitude limited sample of nearly 9000 early-type galaxies, in the redshift range 0.01 < z < 0.3, was selected from the Sloan Digital Sky Survey using morphological and spectral criteria. The sample was used to study how early-type galaxy observables, including luminosity L, effective radius R_o, surface brightness I_o, color, and velocity dispersion sigm

Daniel Eisenstein

As the 2dF Galaxy Redshift Survey and Sloan Digital Sky Survey move toward completion, it is time to ask what the next generation of survey of large-scale structure should be. I discuss some of the cosmological justifications for such surveys and conclude that surveys at z=3 offer a critical advantage in their ability to access linear-regime clustering at sc

S. Malhotra, J. X. Wang, J. E. Rhoads, T. M. Heckman

The Lyman-alpha emitters found at z=4.5 and 5.7 by the Large Area Lyman Alpha (LALA) survey have high equivalent widths in the Lyman-alpha line. Such lines can be produced by narrow-lined active galactic nuclei (AGNs) or by stellar populations with a very high proportion of young, massive stars. To check for Type-II (i.e., narrow-lined) quasars, we obtained

Rolf-Peter Kudritzki, Norbert Przybilla

Because of their enormous intrinsic brightness blue supergiants are ideal stellar objects to be studied spectroscopically as individuals in galaxies far beyond the Local Group. Quantitative spectroscopy by means of efficient multi-object spectrographs attached to 8m-class telescopes and modern NLTE model atmosphere techniques allow us to determine not only i

Andrew F. Nelson, Willy Benz

(abridged) We find that a disk can supply a forming planet with mass at an essentially infinite rate ($\sim1$\mj/25 yr) so that a gap could form very quickly. We show that mass accretion rates faster than $\sim10^{-4}$\mj/yr are not physically reasonable in the limit of either a thin, circumplanetary disk or of a spherical envelope. Planet growth and ultimat

Andrew F. Nelson, Willy Benz

(abridged) We analyze the formation and migration of a proto-Jovian companion in a circumstellar disk in 2d, during the period in which the companion makes its transition from `Type I&#39; to `Type II&#39; migration, using a PPM code. Spiral waves are generated by the gravitational torque of the planet on the disk. Their effects are to cause the planet to mi

Eric F. Bell, Daniel H. McIntosh, Neal Katz, Martin D. Weinberg

We estimate the baryonic (stellar+cold gas) mass function of galaxies in the local Universe by assigning a complete sample of Two Micron All Sky Survey and Sloan Digital Sky Survey galaxies a gas fraction based on a statistical sample of the entire population, under the assumption of a universally-applicable stellar initial mass function. The baryonic mass f

Mario Livio

I examine some recent findings in cosmology and their potential implications for the emergence of life in the universe. In particular, I discuss the requirements for carbon-based life, anthropic considerations with respect to the nature of dark energy, the possibility of time-varying constants of nature, and the question of the rarity of intelligent life.

V. Muccione, L. Ciotti

We describe a particular aspect of the effects of the parent cluster tidal field (CTF) on stellar orbits inside cluster Elliptical galaxies. In particular we discuss, with the aid of a simple numerical model, the possibility that collisionless stellar evaporation from elliptical galaxies is an effective mechanism for the production of the recently discovered

Holly L. Maness, Saeqa D. Vrtilek, Noam Soker, Joel H. Kastner

We revisit Chandra observations of the planetary nebulae NGC 7027 and BD +30 3639 in order to address the question of abundance anomalies in the X-ray emitting gas. Enhanced abundances relative to solar of magnesium (Mg) for NGC 7027 and neon (Ne) for BD +30 3639 are required to fit their X-ray spectra, whereas observations at optical and infrared wavelength

James E. Taylor, Arif Babul

The hierarchical mergers that form the haloes of dark matter surrounding galaxies, groups and clusters are not entirely efficient, leaving substantial amounts of dense substructure, in the form of stripped halo cores or `subhaloes&#39;, orbiting within these systems. Using a semi-analytic model of satellite dynamics, we study the evolution of haloes as they

Martin Bange, Stefan Jordan, Michael Biermann, Thomas Kaempke

We propose an object detection algorithm which is efficient and fast enough to be used in (almost) real time with the limited computer capacities onboard satellites. For stars below the saturation limit of the CCD detectors it is based on a four neighbourhood local maximum criterion in order to find the centre of a stellar image. For saturated stars it is ba

Timothy J. Waskett, Stephen A. Eales, Walter K. Gear, Elizabeth M. Puchnarewicz

First results from XMM-Newton observations of the Canada France Redshift Survey (CFRS) 3hr, 10hr and 14hr fields are presented. Limited regions of two of the XMM surveys (3 and 14hr) are compared to the Canada UK Deep sub-mm Surveys (CUDSS) undertaken with SCUBA. None of the 27 SCUBA sources in the 3hr field are detected by XMM, while one of the 23 SCUBA sou

Gavin Ramsay, Mark Cropper

The XMM-Newton-MSSL survey of polars is a snapshot survey of nearly 40 polars. We present the initial results, with an emphasis on the energy balance in these systems and the number of systems which were observed in a low accretion state. In contrast to the ROSAT results, we find that the vast majority of polars show no `soft X-ray excess&#39;. We find that

Stefano Covino, Gabriele Ghisellini, Davide Lazzati, Daniele Malesani

Gamma-Ray Burst afterglow polarization measurements, in spite of their intrinsic difficulties, have been carried out for a number of events that begins to be adequate to draw some general statistical conclusions. Although the presence of some degree of intrinsic polarization seems to be well established, there are still open problems regarding the polarizati

Maurice H. P. M. van Putten

We present a mechanism for long bursts of gravitational radiation from Kerr black holes surrounded by a torus. These systems are believed to form in core-collapse of massive stars in association with gamma-ray bursts. The torus catalyzes black hole-spin energy mostly into gravitational radiation, with a minor output in winds, thermal and neutrino emissions.

N. N. Shakhvorostova, S. I. Grachev, V. K. Dubrovich

The work is devoted to the investigations of possible observational manifestations of protoobjects related to &#34;dark ages&#34; epoch (10 < z < 1000), before formation of self-luminous galaxies and stars. These objects can distort the cosmic microwave background. Formation of these objects is described in the &#34;pancake theory&#34; and in the model of &#

S. Falter, U. Heber, S. Dreizler, S. L. Schuh

We present time-series spectroscopy and multi-band photometry of the sdBV PG 1605+072 carried out simultaneously at the Calar Alto 2.2m and 3.5m telescopes. The periodogram analysis of the radial velocity curves reveals three frequencies at 2.078, 2.756, and 1.985 mHz for Hbeta and at 2.076, 2.753, and 1.978 mHz for Hgamma. The corresponding radial velocity

D. A. Green, F. R. Stephenson

The available historical records of supernovae occurring in our own Galaxy over the past two thousand years are reviewed. These accounts include the well-recorded supernovae of AD 1604 (Kepler&#39;s SN), 1572 (Tycho&#39;s SN), 1181, 1054 (which produced the Crab Nebula) and 1006, together with less certain events dating back to AD 185. In the case of the sup

H. Edelmann, U. Heber, H. -J. Hagen, M. Lemke

We present the results of a spectral analysis of a large sample of subdwarf B stars selected from follow-up observations of candidates from the Hamburg Quasar Survey. Fundamental parameters (effective temperature, gravity, and helium abundance) were determined by matching synthetic line profiles calculated from model atmospheres to all hydrogen and helium ab

Fabio Fontanot, Pierluigi Monaco, Stefano Borgani

We apply the ZTRACE algorithm to the optical NOG and infra-red PSCz galaxy catalogues to reconstruct the pattern of primordial fluctuations that have generated our local Universe. We check that the density fields traced by the two catalogues are well correlated, and consistent with a linear relation (either in $δ$ or in log(1+$δ$)) with relative bias (of NOG

Andrew F. Nelson

The accurate simulation of collapsed objects requires that a huge range of spatial scales be well resolved if the result is not to be contaminated by numerically induced fragmentation. In this context, `insufficient resolution&#39; means comparable to the local instability wavelength in the system. I define a minimum resolution criterion for simulations of d

K. Coble, P. A. R. Ade, J. J. Bock, J. R. Bond

We present millimeter-wave observations of three extra-galactic and six Galactic sources in the Southern sky. Observations were made at 90, 150, 240 and 400 GHz with resolutions of 18, 10, 14 and 12 arcmin respectively during the 1998 Antarctic long duration balloon flight of BOOMERANG. Observations were also made with the SEST telescope, at 90 and 150 GHz w

J. M. Cordes, T. J. W. Lazio

In Paper I we present a new model for the Galactic distribution of free electrons. In this paper we describe the input data and methodology for determining the structure and parameters of the model. Tables of the input data are provided and several figures are used to demonstrate why particular Galactic structures are needed. We identify lines of sight on wh

N. Z. Scoville, D. T. Frayer, E. Schinnerer, M. Christopher

We present results of a CO(1-0) line survey in a complete sample of 12 low redshift (Z < 0.1), optically bright QSOs (PG QSOs with M_B < -23 mag). Six new CO detections are reported here at levels exceeding I_CO ~2 Jy km/s. Combined with three previously reported detections, we find that 9 of the 12 QSOs have abundant, dense ISMs characteristic of late type

Chris B. Brook, Daisuke Kawata, Brad K. Gibson, Chris Flynn

The present day chemical and dynamical properties of the Milky Way bear the imprint of the Galaxy&#39;s formation and evolutionary history. One of the most enduring and critical debates surrounding Galactic evolution is that regarding the competition between ``satellite accretion&#39;&#39; and ``monolithic collapse&#39;&#39;; the apparent strong correlation

E. Parizot

We propose a new observational test of top-down source models for the ultra-high-energy cosmic-rays (UHECRs), based on the simultaneous observation of two or more photons from the same Galactic hadron jet. We derive a general formula allowing one to calculate the probability of detecting such `multiple events&#39;, for any particular top-down model, once the

Carlos Leiva, Mikhail S. Plyushchay

The nonlinear realization of conformal so(2,d) symmetry for relativistic systems and the dynamical conformal so(2,1) symmetry of nonrelativistic systems are investigated in the context of AdS/CFT correspondence. We show that the massless particle in d-dimensional Minkowski space can be treated as the system confined to the border of the AdS_{d+1} of infinite

Lee Lindblom, Mark A. Scheel

The Einstein evolution equations have been written in a number of symmetric hyperbolic forms when the gauge fields--the densitized lapse and the shift--are taken to be fixed functions of the coordinates. Extended systems of evolution equations are constructed here by adding the gauge degrees of freedom to the set of dynamical fields, thus forming symmetric h

Shamit Kachru, Renata Kallosh, Andrei Linde, Sandip P. Trivedi

We outline the construction of metastable de Sitter vacua of type IIB string theory. Our starting point is highly warped IIB compactifications with nontrivial NS and RR three-form fluxes. By incorporating known corrections to the superpotential from Euclidean D-brane instantons or gaugino condensation, one can make models with all moduli fixed, yielding a su

A. P. Balachandran, G. Immirzi

The Ginsparg-Wilson algebra is the algebra underlying the Ginsparg-Wilson solution of the fermion doubling problem in lattice gauge theory. The Dirac operator of the fuzzy sphere is not afflicted with this problem. Previously we have indicated that there is a Ginsparg-Wilson operator underlying it as well in the absence of gauge fields and instantons. Here w

Yeinzon Rodriguez, Carlos Quimbay

Several works analyzing the new physics contributions from the Left-Right Symmetric Model to the CP violation phenomena in the neutral B mesons can be found in the literature. These works exhibit interesting and experimentally sensible deviations from the Standard Model predictions but at the expense of considering a low right scale \upsilon_R around 1 TeV.

Tiziana Di Matteo, Rupert A. C. Croft, Volker Springel, Lars Hernquist

(abridged) The observed properties of supermassive black holes suggest a fundamental link between their assembly and the formation of their host spheroids. We model the growth and activity of black holes in galaxies using LambdaCDM cosmological hydrodynamic simulations by following the evolution of the baryonic mass component in galaxy potential wells. We fi

Evgeny Ivanov, Luca Mezincescu, Anatoly Pashnev, Paul K. Townsend

The standard quantum states of $n$ complex Grassmann variables with a free-particle Lagrangian transform as a spinor of SO(2n). However, the same `free-fermion&#39; model has a non-linearly realized $SU(n|1)$ symmetry; it can be viewed as the mechanics of a `particle&#39; on the Grassmann-odd coset space $SU(n|1)/U(n)$. We implement a quantization of this mo

Adam C. Durst, Subir Sachdev, N. Read, S. M. Girvin

Recent measurements of a 2D electron gas subjected to microwave radiation reveal a magnetoresistance with an oscillatory dependence on the ratio of radiation frequency to cyclotron frequency. We perform a diagrammatic calculation and find radiation-induced resistivity oscillations with the correct period and phase. Results are explained via a simple picture

S. Sabatini, J. Davies, R. Scaramella, R. Smith

The widely varying dwarf galaxy counts in different environments provide a strong challenge to standard hierarchical clustering models. The luminosity function is not universal, but seems to be strongly dependent upon environment. In this paper we describe an automated procedure for detecting and measuring very low surface brightness (LSB) features in deep C

L. Limot, T. Maroutian, P. Johansson, R. Berndt

We report a quantitative low-temperature Scanning Tunneling Spectroscopy (STS)study on the Ag(111) surface state over an unprecedented range of currents (50 pA to 6 $μ$A)through which we can tune the electric field in the tunnel junction of the microscope. We show that in STS a sizeable Stark effect causes a shift of the surface state binding energy $E_{0}$.

F. J. Castander, E. Treister, T. J. Maccarone, P. S. Coppi

We present a new X-ray selected high redshift quasar CXOCY J125304.0-090737 at z=4.179, discovered by the Calan-Yale Deep Extragalactic Research (CYDER) Survey. This quasar is the fifth X-ray selected high redshift radio quiet quasar ($z>4$) found so far. Here, we present its observed properties which are characterized by its relative optical and X-ray faint

Pia Mukherjee, Kim Coble, Mark Dragovan, Ken Ganga

We constrain Galactic foreground contamination of the Python V cosmic microwave background anisotropy data by cross correlating it with foreground contaminant emission templates. To model foreground emission we use 100 and 12 $μ$m dust emission templates and two point source templates based on the PMN survey. The analysis takes account of inter-modulation co

Jozef Strecka, Michal Jascur

Ground-state properties of the spin-1/2 and spin-1 Ising-Heisenberg model on doubly decorated planar lattices, are investigated in detail. On the basis of the mapping transformation method, we prove an existence of unusual quantum phases which occur due to the competition between Ising-type and XXZ anizotropic Heisenberg-type interactions. Effect of the crys

Jozef Strecka, Michal Jascur

The mapping transformation technique is applied to obtain exact results for the spin-1/2 and spin-S (S=1/2,1) Ising-Heisenberg antiferromagnetic chain in the presence of an external magnetic field. Within this scheme, a field-induced first-order metamagnetic transition resulting in multiplateau magnetization curves, is investigated in detail. It is found tha

Y. Y. Proskuryakov, Z. D. Kvon, A. K. Savchenko

In this work we have studied the parallel magnetoresistance of a 2DEG near a vicinal silicon surface. An unusual, linear magnetoconductance is observed in the fields up to $B = 15$ T, which we explain by the effect of spin olarization on impurity scattering. This linear magnetoresistance shows strong anomalies near the boundaries of the minigap in the electr

Dominic Clancy, Raf Guedens, Andrew R Liddle

In two recent papers we explored the modifications to primordial black hole physics when one moves to the simplest braneworld model, Randall--Sundrum type II. Both the evaporation law and the cosmological evolution of the population can be modified, and additionally accretion of energy from the background can be dominant over evaporation at high energies. In

F. S. Navarra, O. V. Utyuzh, G. Wilk, Z. Wlodarczyk

Using the information theory approach, in both its extensive and nonextensive versions, we estimate the inelasticity parameter $K$ of hadronic reactions together with its distribution and energy dependence from $p\bar{p}$ and $pp$ data. We find that the inelasticity remains essentially constant in energy except for a variation around $K\sim 0.5$, as was orig

H. O. Girotti

We start by reviewing the formulation of noncommutative quantum mechanics as a constrained system. Then, we address to the problem of field theories defined on a noncommutative space-time manifold. The Moyal product is introduced and the appearance of the UV/IR mechanism is exemplified. The emphasis is on finding and analyzing noncommutative quantum field th

Otfried Gühne, Philipp Hyllus

In this paper we describe how three qubit entanglement can be analyzed with local measurements. For this purpose we decompose entanglement witnesses into operators which can be measured locally. Our decompositions are optimized in the number of measurement settings needed for the measurement of one witness. Our method allows to detect true threepartite entan

Patrick Huber, Walter Winter

We show that for a neutrino factory baseline of $L \sim 7300 km - 7 600 km$ a ``clean&#39;&#39; measurement of $\sin^2 2 θ_{13}$ becomes possible, which is almost unaffected by parameter degeneracies. We call this baseline &#34;magic&#34; baseline, because its length only depends on the matter density profile. For a complete analysis, we demonstrate that the

N. T. Yilmaz

The dualised formulation of the symmetric space sigma model is peformed for a general scalar coset G/K where G is a maximally non-compact group and K is it&#39;s maximal compact subgroup.By using the twisted self-duality condition the general form of the first-order equations are obtained.The results are applied to the example of SL(2,R)/SO(2) scalar manifol

Georg Foltin

We consider the signed density of the extremal points of (two-dimensional) scalar fields with a Gaussian distribution. We assign a positive unit charge to the maxima and minima of the function and a negative one to its saddles. At first, we compute the average density for a field in half-space with Dirichlet boundary conditions. Then we calculate the charge-

I. M. Khalatnikov, A. Yu. Kamenshchik, M. Martellini, A. A. Starobinsky

The quasi-isotropic inhomogeneous solution of the Einstein equations near a cosmological singularity in the form of a series expansion in the synchronous system of reference, first found by Lifshitz and Khalatnikov in 1960, is generalized to the case of a two-fluid cosmological model. This solution describes non-decreasing modes of adiabatic and isocurvature

G. R. Knapp, D. Pourbaix, I. Platais, A. Jorissen

We analyze the K band luminosities of a sample of galactic long-period variables using parallaxes measured by the Hipparcos mission. The parallaxes are in most cases re-computed from the Hipparcos Intermediate Astrometric Data using improved astrometric fits and chromaticity corrections. The K band magnitudes are taken from the literature and from measuremen

R. Ouyed, P. Keränen, J. Maalampi

We explore acceleration of ions in the Quark Nova (QN) scenario, where a neutron star experiences an explosive phase transition into a quark star (born in the propeller regime). In this picture, two cosmic ray components are isolated: one related to the randomized pulsar wind and the other to the propelled wind, both boosted by the ultra-relativistic Quark N

Paolo Cea

P-Stars are a new class of compact stars made of up and down quarks in beta-equilibrium with electrons in an Abelian chromomagnetic condensate. We show that P-Stars are able to account for compact stars with R < 6 Km, as well as stars with radius comparable with canonical Neutron Stars. We find that cooling curves of P-Stars compare rather well with observat

G. T. Lenters, P. M. Woods, J. E. Goupell, C. Kouveliotou

The Soft Gamma Repeater, SGR 1900+14, entered a new phase of activity in April 2001 initiated by the intermediate flare recorded on April 18. Ten days following this flare, we discovered an abrupt increase in the source flux between consecutive RXTE orbits. This X-ray flux excess decayed over the next several minutes and was subsequently linked to a high flu

Sergei A. Klioner

We show how to derive the equations of light propagation in the gravitational field of uniformly moving mass monopoles without formulating and integrating the differential equations of light propagation in that field. The well-known equations of light propagation in the gravitational field of a motionless mass monopole are combined with a suitable Lorentz tr

Tota Nakamura, Yoshiyuki Ito

We propose a new quantum Monte Carlo algorithm which realizes a relaxation intrinsic to the original quantum system. The Monte Carlo dynamics satisfies the dynamic scaling relation $τ\sim ξ^z$ and is independent of the Trotter number. Finiteness of the Trotter number just appears as the finite-size effect. An infinite Trotter number version of the algorithm

Robert Fleischer

Decays of neutral B mesons originating from $b\to D r$ $(r\in\{s,d\})$ processes, i.e. $B_d\to DK_{S(L)}$, $B_s\to Dη^{(&#39;)}, Dϕ, ...$ $(r=s)$ and $B_s\to DK_{S(L)}$, $B_d\to Dπ^0, Dρ^0, ...$ $(r=d)$ modes, offer valuable insights into CP violation. Here the neutral $D$ mesons may be observed through $D\to f_\pm$ or $D\to f_{NE}$, where $f_\pm$ and $f_{NE

Robert Fleischer

We point out that decays of the kind $B_d\to D_\pm K_{S(L)}$ and $B_s\to D_\pmη^{(&#39;)},D_\pmϕ, ...$, where $D_+$ and $D_-$ denote the CP-even and CP-odd eigenstates of the neutral D-meson system, respectively, provide very efficient, theoretically clean determinations of the angle $γ$ of the unitarity triangle. In this new strategy, we use the $B^0_q$--$\

Nicklas Ohlsson, Mattias Nilsson, Stefan Kroll

A photon echo experiment has been performed using accumulated highly attenuated laser pulses. We show experimentally that the photon echo process can be performed with, on the average, less than one photon in each pair of excitation pulses. The results support an interpretation where this non-linear process can be performed with, on the average, less than on

Suayyip Salim Ozkurt

Withdrawn by arXiv administration because the text and equations were plagiarized almost entirely verbatim from hep-th/9610131 .

Yan-Gang Miao, Nobuyoshi Ohta

By using the systematic approach of parent action method, we derive one Weyl-noninvariant and two Weyl-invariant actions of bosonic $p$-branes ($p\geq 2$) starting from the Nambu-Goto action, and establish the duality symmetries in this set of four actions. Moreover, we discover a new bosonic $p$-brane action (including the string theory) and deduce two corr

Chao-Hsi Chang, Jian-Ping Ma, Zong-Guo Si

The quark recombination mechanism is proposed to explain the asymmetry between production rates of $D^+$ and of $D^-$ in their inclusive productions, and also asymmetries for other charmed hadrons. These asymmetries are observed in experiment and are called as leading particle effects. In this work we give a general analysis for contributions of quark recomb

Pia Mukherjee, Yun Wang

In order to constrain and possibly detect unusual physics during inflation, we allow the power spectrum of primordial matter density fluctuations, P_{in}(k), to be an arbitrary function in the estimation of cosmological parameters from data. The multi-resolution and good localization properties of orthogonal wavelets make them suitable for detecting features

L. -M. Duan, H. J. Kimble

We propose an efficient scheme to engineer multi-atom entanglement by detecting cavity decay through single-photon detectors. In the special case of two atoms, this scheme is much more efficient than previous probabilistic schemes, and insensitive to randomness in the atom&#39;s position. More generally, the scheme can be used to prepare arbitrary superposit

Stephane Beauregard, Gilles Brassard, Jose M. Fernandez

In this paper we discuss the problem of performing elementary finite field arithmetic on a quantum computer. Of particular interest, is the controlled-multiplication operation, which is the only group-specific operation in Shor&#39;s algorithms for factoring and solving the Discrete Log Problem. We describe how to build quantum circuits for performing this o