May 2002 arXiv papers — page 12

Alessandro Silva, Yuval Oreg, Yuval Gefen

A small quantum dot coupled to two external leads is considered. Different signs of the dot-leads coupling matrix elements give rise to qualitatively different behavior of physical observables such as the conductance, the phase of the transmission amplitude and the differential capacitance of the dot. For certain relative signs the conductance may vanish at

Cinzia De Leo, Giacomo Rotoli

Many experiments on high-temperature superconductors have shown paramagnetic behavior when the sample is field cooled. The paramagnetism was first attributed to a d-wave order parameter creating pi-junctions in the samples. However, the same effect was later discovered in traditional low-temperature superconductors and conventional Josephson-junction arrays

Serge Galam, Pierre-Vincent Koseleff

Few years ago, application of the mean field Bethe scheme on a given system was shown to produce a systematic change of the system intrinsic symmetry. For instance, once applied on a ferromagnet, individual spins are no more equivalent. Accordingly a new loopwise mean field theory was designed to both go beyond the one site Weiss approach and yet preserve th

P. G. Bolhuis, A. A. Louis

Polymer chains in colloid-polymer mixtures can be coarse-grained by replacing them with single soft particles interacting via effective polymer-polymer and polymer-colloid pair potentials. Here we describe in detail how Ornstein-Zernike inversion techniques, originally developed for atomic and molecular fluids, can be generalized to complex fluids and used t

Daniel Biegel, Michael Karbach, Gerhard Muller

We use the exact determinantal representation derived by Kitanine, Maillet, and Terras for matrix elements of local spin operators between Bethe wave functions of the one-dimensional s=1/2 Heisenberg model to calculate and numerically evaluate transition rates pertaining to dynamic spin structure factors. For real solutions z_1,...,z_r of the Bethe ansatz eq

A. Oosawa, T. Takamasu, K. Tatani, H. Abe

KCuCl$_3$ is a three-dimensional coupled spin-dimer system and has a singlet ground state with an excitation gap $Δ/k_{\rm B}=31$ K. High-field magnetization measurements for KCuCl$_3$ have been performed in static magnetic fields of up to 30 T and in pulsed magnetic fields of up to 60 T. The entire magnetization curve including the saturation region was obt

F. Calvo

The multiple range random walk algorithm recently proposed by Wang and Landau [Phys. Rev. Lett. 86, 2050 (2001)] is adapted to the computation of free energy profiles for molecular systems along reaction coordinates. More generally, we show how to extract partial averages in various statistical ensembles without invoking simulations with constraints, biasing

Yup Kim, T. S. Kim, Hyunggyu Park

We investigate the scaling properties of the interface fluctuation width for the $Q$-mer and $Q$-particle-correlated deposition-evaporation models. These models are constrained with a global conservation law that the particle number at each height is conserved modulo $Q$. In equilibrium, the stationary roughness is anomalous but universal with roughness expo

Xiu-Kun Hua, Yin-Zhong Wu, Zhen-Ya Li

In this paper, we investigate the electron self-energy and effective mass in a single heterostructure using Green-function method. Numerical calculations of the electron self-energy and effective mass for GaAs/AlAs heterostructure are performed. The results show that the self energy (effective mass) of electron, which incorporate the energy of electron coupl

T. M. Mishonov, E. S. Penev, J. O. Indekeu

An analytical result for the renormalization of the jump of the heat capacity Delta C/C_N by the anisotropy of the order parameter is derived within the framework of the very recent model proposed by Posazhennikova, Dahm and Maki [cond-mat/0204272, submitted to Europhys. Lett.], for both oblate and prolate anisotropy. The graph of Delta C/C_N versus the rati

A. Barrat, E. Trizac

We consider the problem of determining the granular temperatures of the components of a homogeneous binary heated mixture of inelastic hard spheres, in the framework of Enskog kinetic theory. Equations are derived for the temperatures of each species and their ratio, which is different from unity, as may be expected since the system is out of equilibrium. We

M. Sztyren

The bi-continuum model composed of two interpenetrating and dynamically coupled material continua is analysed as a simplified but relatively accurate way to describe some physical phenomena in crystalline solids. The essential novelty of our approach consists in treating a crystalline medium as bi-continuum, even if the crystalline lattice is structurally si

Barton J. Pritzl, Taft E. Armandroff, George H. Jacoby, Gary S. Da Costa

We have surveyed Andromeda VI, a dwarf spheroidal galaxy companion to M31, for variable stars using F450W and F555W observations obtained with the Hubble Space Telescope. A total of 118 variables were found, with 111 being RR Lyrae, 6 anomalous Cepheids, and 1 variable we were unable to classify. We find that the Andromeda VI anomalous Cepheids have properti

M. Loewenstein, R. Mushotzky

We determine the total enclosed mass profile from 0.7 to 35 kpc in the elliptical galaxy NGC 4636 based on the hot interstellar medium temperature profile measured using the Chandra X-ray Observatory, and other X-ray and optical data. The total mass increases as radius to the power 1.2 to a good approximation over this range in radii, attaining a total mass-

Antony A Stark, Adair P. Lane, Christopher L. Martin, Richard Chamberlin

The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) is a 1.7-meter diameter offset Gregorian instrument located at the NSF Amundsen-Scott South Pole Station. This site is exceptionally dry and cold, providing opportunities for Terahertz observations from the ground. Preliminary analysis of recent site testing results shows that the zenith t

G. Golse, J. -P. Kneib, G. Soucail

We use a strong lensing inversion in the cluster of galaxies AC 114 to derive constraints on the cosmological parameters Omega_M0 and Omega_Lambda. If it is possible to measure spectroscopically the redshifts of many multiple images then one can in principle constrain (Omega_M0,Omega_Lambda) through ratios of angular diameter distances, independently of any

Dipanjan Mitra, Joanna M. Rankin

In this paper we return to the old problem of conal component-pair widths and profile dimensions. Observationally, we consider a set of 10 pulsars with prominent conal component pairs, for which well measured profiles exist over the largest frequency range now possible. Apart from some tendency to narrow at high frequency, the conal components exhibit almost

I. Saviane, L. Rizzi, E. V. Held, F. Bresolin

We present new results from optical spectroscopy of the brightest Hii region in the dwarf irregular galaxy UKS 1927-177 in Sagittarius (SagDIG). From high signal-to-noise spectra, reddening-corrected line flux ratios have been measured with typical uncertainties of a few percent, from which the oxygen abundance is rediscussed, and new abundance estimates are

Sidney van den Bergh

The prints of the Palomar Sky Survey, luminosity classificaiton and radial velocities were used to assign all northern Shapley-Ames galaxies to either (1) field, (2) group, or (3) cluster environments. This information for 930 galaxies shows no evidence for a dependence of bar frequency on galaxy environment. This suggests that the formation of a bar in a di

E. M. Drobyshevski

The daemon-stimulated proton decay is capable of providing an appreciable part of the Sun luminosity as well as nonelectron flavor component in the solar neutrino flux. This follows (1) from our experiments on detection of negative daemons in Earth-crossing orbits, which give ~1 microsec for the decay time of a daemon-containing proton, and (2) from an estim

B. Aracil, P. Petitjean, A. Smette, J. Surdej

We present HST STIS observations of four quasar pairs with redshifts 0.84<z_em<1.56 and angular separation 2-3 arcmin corresponding to ~ 1-1.5 h^-1_50 Mpc transverse proper distance at z ~ 0.9. We study the distribution of velocity differences between nearest neighbor HI Lyman_alpha absorption lines detected in the spectra of adjacent QSOs in order to search

Peter Nugent, Alex Kim, Saul Perlmutter

The measurement of the cosmological parameters from Type Ia supernovae hinges on our ability to compare nearby and distant supernovae accurately. Here we present an advance on a method for performing generalized K-corrections for Type Ia supernovae which allows us to compare these objects from the UV to near-IR over the redshift range 0<z<2. We discuss the e

E. D. Reese, J. E. Carlstrom, M. Joy, J. J. Mohr

We determine the distances to 18 galaxy clusters with redshifts ranging from z~0.14 to z~0.78 from a maximum likelihood joint analysis of 30 GHz interferometric Sunyaev-Zel&#39;dovich effect (SZE) and X-ray observations. We model the intracluster medium (ICM) using a spherical isothermal beta model. We quantify the statistical and systematic uncertainties in

A. V. Alakoz, S. V. Kalenskii, V. G. Promislov, L. E. B. Johansson

The results of a survey of 63 galactic star-forming regions in the 6_K-5_K and 5_K-4_K methyl acetylene lines at 102 and 85 GHz, respectively, are presented. Fourty-three sources were detected at 102 GHz, and twenty-five at 85 GHz. Emission was detected towards molecular clouds with kinetic temperatures 20-60 K (so-called ``warm clouds&#39;&#39;). The CH3CCH

H. Beuther, A. Walsh, P. Schilke, T. K. Sridharan

We present a comparison of ClassII CH3OH and H2O masers at high spatial resolution in a sample of 29 massive star-forming regions. Absolute positions of both maser types are compared with mm dust continuum, cm continuum and mid-infrared sources. Spatial correlations of the different tracers and kinematic signatures are discussed.

A. De Rosa, A. C. Fabian, L. Piro

In this letter we present analysis of BeppoSAX data from a long look at the Seyfert 1 galaxy NGC 7469. The presence of a soft excess below 0.8 keV is confirmed by our analysis and no warm absorber component is required to fit the spectrum. A complex iron emission line and the Compton reflection hump are clearly detected. The profile of the line is too broad

Didier Barret

ECLAIRs is a French microsatellite devoted to the observation of the prompt optical and X-ray emission of GRBs. For about 100 GRBs/yr, independent of their duration, ECLAIRs will provide high time resolution high sensitivity spectral coverage from a few eV up to ~50 keV and localization to ~5 arcsec in near real time. This capability is achieved by combining

M. Motoki, T. Sanuki, S. Orito, K. Abe

The vertical absolute fluxes of atmospheric muons and muon charge ratio have been measured precisely at different geomagnetic locations by using the BESS spectrometer. The observations had been performed at sea level (30 m above sea level) in Tsukuba, Japan, and at 360 m above sea level in Lynn Lake, Canada. The vertical cutoff rigidities in Tsukuba (36.2 N,

Peter Schuecker, Luigi Guzzo, Chris A. Collins, Hans Boehringer

The Karhunen-Loéve (KL) eigenvectors and eigenvalues of the sample correlation matrix are used to analyse the spatial fluctuations of the REFLEX clusters of galaxies. The method avoids the disturbing effects of correlated power spectral densities which affects all previous cluster measurements on Gpc scales. Comprehensive tests use a large set of independent

J. Rodriguez, S. Corbel, E. Kalemci, J. Tomsick

We report on timing and spectral observations of the microquasar XTE J1550-564 during its 2000 outburst made by the Rossi X-ray Timing Experiment (RXTE). We study the spectral properties of the source during both the rise to the outburst and its decline. We observe transitions from a low hard state to an intermediate state, and vice versa, before the source

B. Famaey, K. Van Caelenberg, H. Dejonghe

We present new equilibrium component distribution functions that depend on three analytic integrals in a Stackel potential, and that can be used to model stellar discs of galaxies. These components are generalizations of two-integral ones and can thus provide thin discs in the two-integral approximation. Their most important properties are the partly analyti

J. J. M. in &#39;t Zand, C. B. Markwardt, A. Bazzano, M. Cocchi

SAX J1711.6-3808 is an X-ray transient in the Galactic bulge that was active from January through May of 2001 and whose maximum 1-200 keV luminosity was measured to be 5X10-9 erg/s/cm2 which is less than ~25% of the Eddington limit, if placed at a distance equal to that of the galactic center. We study the X-ray data that were taken of this moderately bright

Kunegunda E. Belle, Steve B. Howell, Martin Sirk, Mark E. Huber

On 2000 May 5, we began a large multi-wavelength campaign to study the intermediate polar, EX Hydrae. The simultaneous observations from six satellites and four telescopes were centered around a one million second observation with EUVE. Although EX Hydrae has been studied previously with EUVE, our higher signal-to-noise observations present new results and c

F. Euchner, S. Jordan, K. Beuermann, B. T. Gaensicke

We have computed optical Zeeman spectra of magnetic white dwarfs for field strengths between 10 and 200MG and effective temperatures between 8000 and 40000K. They form a database containing 20628 sets of flux and circular polarization spectra. A least-squares optimization code based on an evolutionary strategy can recover relatively complex magnetic field to

A. T. Bajkova

We propose a new approach for the accurate reconstruction of cosmic microwave background distributions from observations containing in addition to the primary fluctuations the radiation from unresolved extragalactic point sources and pixel noise. The approach uses some effective realizations of the well-known maximum entropy method and principally takes into

Joel Giedt

We discuss string scale unification facilitated by exotic matter with masses at intermediate scales, between the observable sector supersymmetry breaking scale and the string scale. We point out a mechanism by which string scale unification may occur while producing a (lower) virtual unification scale independent of the location of the intermediate scale and

Joel Giedt

We compute the component field 4-dimensional N=1 supergravity Lagrangian that is obtained from a superfield Lagrangian in the U(1)_K formalism with a linear dilaton multiplet. All fermionic terms are presented. In a variety of important ways, our results generalize those that have been reported previously, and are flexible enough to accomodate many situation

Yeong E. Kim, Alexander L. Zubarev

A time-dependent Kohn-Sham (KS) like theory is presented for N bosons in thre e and lower-dimensional traps. We derive coupled equations, which allow one to calculate the energies of elementary excitations. A rigorous proof is given to show that the KS like equation correctly describes properties of the one-dimensional condensate of impenetrable bosons in a

P. Di Vecchia, A. Lerda, P. Merlatti

We consider supergravity solutions of D5 branes wrapped on supersymmetric 2-cycles and use them to discuss relevant features of four-dimensional N=1 and N=2 super Yang-Mills theories with gauge group SU(n). In particular in the N=1 case, using a gravitational dual of the gaugino condensate, we obtain the complete NSVZ beta-function. We also find non-perturba

Steven Detweiler, Eirini Messaritaki, Bernard F. Whiting

The foundations are laid for the numerical computation of the actual worldline for a particle orbiting a black hole and emitting gravitational waves. The essential practicalities of this computation are here illustrated for a scalar particle of infinitesimal size and small but finite scalar charge. This particle deviates from a geodesic because it interacts

K. D. McCarthy, N. Prokof&#39;ev, M. T. Tuominen

We study the tunneling conductance of nano-scale quantum ``shuttles&#39;&#39; in connection with a recent experiment (H. Park et al., Nature, 407, 57 (2000)) in which a vibrating C^60 molecule was apparently functioning as the island of a single electron transistor (SET). While our calculation starts from the same model of previous work (D. Boese and H. Scho

Serge Massar, Stefano Pironio, Jeremie Roland, Bernard Gisin

We derive both numerically and analytically Bell inequalities and quantum measurements that present enhanced resistance to detector inefficiency. In particular we describe several Bell inequalities which appear to be optimal with respect to inefficient detectors for small dimensionality d=2,3,4 and 2 or more measurement settings at each side. We also general

Jinwu Ye

Both the gauge-invariant fermion Green function and gauge-dependent conventional Green function in $ 2+1 $ dimensional QED are studied in the large $ N $ limit. In temporal gauge, the infra-red divergence of gauge-dependent Green function is found to be regulariable, the anomalous dimension is found to be $ η= \frac{64}{3 π^{2} N} $. This anomalous dimension

L. Homer, Scott F. Anderson, Stefanie Wachter, Bruce Margon

We have obtained Hubble Space Telescope/STIS low-resolution ultraviolet spectra of the X-ray pulsar 4U 1626-67 (=KZ TrA); 4U 1626-67 is unusual even among X-ray pulsars due to its ultra-short binary period (P=41.4 min) and remarkably low mass-function (<1.3e-6 Msun). The far-UV spectrum was exposed for a total of 32ks and has sufficient signal-to-noise to re

Denis A. Gorokhov, Daniel S. Fisher, Gianni Blatter

The dynamics of an elastic medium driven through a random medium by a small applied force is investigated in the low-temperature limit where quantum fluctuations dominate. The motion proceeds via tunneling of segments of the manifold through barriers whose size grows with decreasing driving force $f$. In the limit of small drive, at zero-temperature the aver

F. Venturini, R. Hackl, U. Michelucci

In a recent letter Blumberg and collaborators claim that a non-monotonic $d_{x^2-y^2}$ form for the superconducting order parameter is required to explain their Raman scattering measurements in Nd$_{2-x}$Ce$_x$CuO$_4$ . In this comment we show with a simple model calculation that the basis for this conclusion is insufficient. The proposed functional dependen

Steven R. Dahl, Christine M. Hrenya, Vicente Garzo, James W. Dufty

An isolated mixture of smooth, inelastic hard spheres supports a homogeneous cooling state with different kinetic temperatures for each species. This phenomenon is explored here by molecular dynamics simulation of a two component fluid, with comparison to predictions of the Enskog kinetic theory. The ratio of kinetic temperatures is studied for two values of

Jessica Millar, N. J. A. Sloane, Neal E. Young

A generalization of the Seidel-Entringer-Arnold method for calculating the alternating permutation numbers (or secant-tangent numbers) leads to a new operation on integer sequences, the Boustrophedon transform.

Geoffrey T. Bodwin, Andrea Petrelli

We compute corrections of relative order v^4 to the rates for the decays of ^1S_0 heavy quarkonium into two photons and into light hadrons and for the decays of ^3S_1 heavy quarkonium into a lepton pair and into light hadrons. In particular, we compute the coefficients of the decay operators that have the same quantum numbers as the heavy quarkonium. We also

Yasuaki Hikida, Yuji Sugawara

We study the superstring theory on pp-wave background with NSNS-flux that is realized as the Penrose limit of AdS_3 x S^3 x M^4, where M^4 is T^4 or T^4/Z_2(~ K3). Quantizing this system in the covariant gauge, we explicitly construct the space-time supersymmetry algebra and the complete set of DDF operators. We analyse the spectrum of physical states by usi

C. G. Beneventano, E. M. Santangelo, A. Wipf

We give an expression, in terms of boundary spectral functions, for the spectral asymmetry of the Euclidean Dirac operator in two dimensions, when its domain is determined by local boundary conditions, and the manifold is of product type. As an application, we explicitly evaluate the asymmetry in the case of a finite-length cylinder, and check that the outco

R. Casalbuoni, R. Gatto, G. Nardulli

The recent study by Bowers and Rajagopal on the possible structures for the QCD crystalline color superconducting phase favors a cubic structure and allows for a first discussion of the QCD dynamics in the crystalline phase. The cubic structure leads to complete breaking of traslation invariance and to three phonon modes. We discuss the expected form of the

Gh. -S. Paraoanu

A ring-shaped array of Bose-Einstein condensed atomic gases can display circular currents if the relative phase of neighboring condensates becomes locked to certain values. It is shown that, irrespective of the mechanism responsible for generating these states, only a restricted set of currents are stable, depending on the number of condensates, on the inter

Guang-You Qin, W. Z. Deng, Z. G. Xiao, H. Q. Zheng

A detailed analysis to the [1,2] Padé approximation to the $ππ$ scattering 2--loop amplitudes in chiral perturbation theory is made.

Shibaji Roy

Recently the time dependent solutions of type II supergravities in $d = 10$, with the metric having the symmetry $ISO(p+1) \times SO(8-p, 1)$ have been given by two groups (Chen-Gal&#39;tsov-Gutperle (CGG), [hep-th/0204071] and Kruczenski-Myers-Peet (KMP), [hep-th/0204144]). The supergravity solutions correspond to space-like D$p$-branes in type II string th

Heng Fan, Hiroshi Imai, Keiji Matsumoto, Xiang-Bin Wang

We study the phase-covariant quantum cloning machine for qudits, i.e. the input states in d-level quantum system have complex coefficients with arbitrary phase but constant module. A cloning unitary transformation is proposed. After optimizing the fidelity between input state and single qudit reduced density opertor of output state, we obtain the optimal fid

Tigran Hakobyan

The Lieb-Shultz-Mattis theorem is extended to Heisenberg chains with long-range interactions. We prove that the half-integer spin chain has no gap, if it possesses unique ground state and the exchange decays faster than the inverse-square of distance between spins. The results can be extended to a wide class of one-dimensional models.

V. N. Pervushin, D. V. Proskurin

The identification of a cosmic scale function with the volume integral of a spacelike hypersurface defines the cosmic evolution in General Relativity as a collective motion along a geodesic in the field space of the metric components, considered as the coset of the affine group over the Lorentz one. The Friedmann equations are derived out of the homogeneous

Koya Abe etal

The structure of three-jet e+e- -> b bbar g events has been studied using hadronic Z0 decays recorded in the SLD experiment at SLAC. Three-jet final states were selected and the CCD-based vertex detector was used to identify two of the jets as b or bbar; the remaining jet in each event was tagged as the gluon jet. Distributions of the gluon energy and polar

E. Friedman

Several mechanisms of density dependence of the s-wave repulsion in pionic atoms, beyond the conventional model, are tested by parameter fits to a large (106 points) set of data from $^{16}$O to $^{238}$U, including `deeply bound&#39; states in $^{205}$Pb. Special attention is paid to the proper choice of nuclear density distributions. A density-dependent is

Saebyok Bae, Byungchul Chung, P. Ko

We present a comprehensive analysis on the MSSM Higgs sector CP violation at photon colliders including the chargino contributions as well as the contributions of other charged particles. The chargino loop contributions can be important for the would-be CP odd Higgs production at photon colliders. Polarization asymmetries are indispensable in determining the

G. S. Dias, E. L. Graça, R. de Lima Rodrigues

The connection between the supersymmetric quantum mechanics involving two-component eigenfunctions and the stability equation associated with two classical configurations is investigated, and a matrix superpotential is deduced. The issue of stability is ensured for the Bogomol&#39;nyi-Prasad-Sommerfield (BPS) states on two domain walls in a scalar potential

Itzhak Bars

It is shown that all the states in AdS(5) x S(5) supergravity have zero eigenvalue for the all Casimir operators of its symmetry group SU(2,2|4). To compute this universal zero in supergravity we refine the oscillator methods for studying the lowest weight unitary representations of SU(N,M|R,S). We solve the reduction problem when one multiplies an arbitrary

Martin Schaden

A simple quantum model explains the Levy-unstable distributions for individual stock returns observed by ref.[1]. The probability density function of the returns is written as the squared modulus of an amplitude. For short time intervals this amplitude is proportional to a Cauchy-distribution and satisfies the Schroedinger equation with a non-hermitian Hamil

Chaiho Rim, Jae Hyung Yee

In non-commutative field theories conventional wisdom is that the unitarity is non-compatible with the perturbation analysis when time is involved in the non-commutative coordinates. However, as suggested by Bahns et.al. recently, the root of the problem lies in the improper definition of the time-ordered product. In this article, functional formalism of S-m

Howard Barnum

Quantum information and computation may serve as a source of useful axioms and ideas for the quantum logic/quantum structures project of characterizing and classifying types of physical theories, including quantum mechanics and classical mechanics. The axiomatic approach of quantum structures may help isolate what aspects of quantum mechanics are responsible

Howard Barnum, Claude Crepeau, Daniel Gottesman, Adam Smith

Authentication is a well-studied area of classical cryptography: a sender S and a receiver R sharing a classical private key want to exchange a classical message with the guarantee that the message has not been modified by any third party with control of the communication line. In this paper we define and investigate the authentication of messages composed o

Gh. -S. Paraoanu

In the framework of Lindblad theory for open quantum systems, we calculate the entropy of a damped quantum harmonic oscillator which is initially in a quasi-free state. The maximally predictable states are identified as those states producing the minimum entropy increase after a long enough time. In general, the states with a squeezing parameter depending on

D. A. Slavnov

In the work it is shown that the principles &#34;the objective local theory&#34; and corollaries of the standard quantum mechanics are not in such antagonistic inconsistency as it is usually supposed. In the framework of algebraic approach, the postulates are formulated which allow constructing the updated mathematical scheme of quantum mechanics. This schem

Anjana Sinha, Rajkumar Roychoudhury

We construct isospectral partner potentials of a complex PT-invariant potential, viz., V(x) = V_1 sech ^2 x - i V_2 sech x tanh x using Darboux&#39;s method. Oneset of isospectral potentials are obatined which can be termed &#39;Satellite potentials&#39;, in the sense that they are pf the same form as the original potential. In a particular case, the supersy

Katarzyna Krajewska, Jerzy Z. Kaminski

A two-dimensional model of an electron moving under the influence of an attractive zero-range potential as well as external magnetic and electric fields is analyzed. We prove by numerical investigations that there are formed such resonances which manifest a peculiar dependance on the electric field intensity, i.e., although the electric field increases, the

C. M. Ko, Z. W. Lin, S. Pal

Effects of partonic interactions in heavy ion collisions at RHIC are studied in a multiphase transport model (AMPT) that includes both initial partonic and final hadronic interactions.It is found that a large parton scattering cross section is needed to understand the measured elliptic flow of pions and two-pion correlation function.

Andrea Meucci, Carlotta Giusti, Franco Davide Pacati

We analyze the role of meson exchange currents (MEC) in photon- and electron-induced one nucleon emission reactions in a fully relativistic model. The relativistic mean field theory is used for the bound state and the Pauli reduction for the scattering state. Direct 1-body and exchange 2-body terms in the nuclear current are considered. Results for the 12C(g

P. Lubinski, A. Grochulska, T. von Egidy, K. Gulda

A natural gold target was irradiated with the antiproton beam from the Low Energy Antiproton Ring at CERN. Antiprotons of 200 MeV/c momentum were stopped in a thick target, products of their annihilations on Au nuclei were detected using the off-line gamma-ray spectroscopy method. In total, yields for 114 residual nuclei were determined, providing a data set

L. Ts. Adzhemyan, N. V. Antonov, M. V. Kompaniets, A. N. Vasil&#39;ev

The field theoretic renormalization group is applied to the stochastic Navier--Stokes equation that describes fully developed fluid turbulence. The complete two-loop calculation of the renormalization constant, the beta function and the fixed point is performed. The ultraviolet correction exponent, the Kolmogorov constant and the inertial-range skewness fact

David C. Brydges, John Z. Imbrie

This is the second of two papers on the end-to-end distance of a weakly self-repelling walk on a four dimensional hierarchical lattice. It completes the proof that the expected value grows as a constant times \sqrt{T} log^{1/8}T (1+O((log log T)/log T)), which is the same law as has been conjectured for self-avoiding walks on the simple cubic lattice Z^4. -

Thomas C. Hales

The classical honeycomb conjecture asserts that any partition of the plane into regions of equal area has perimeter at least that of the regular hexagonal honeycomb tiling. Pappus discusses this problem in his preface to Book V. This paper gives the first general proof of the conjecture. The revision is the published version, which allows disconnected honeyc

Thomas C. Hales

This is the sixth in a series of papers giving a proof of the Kepler conjecture, which asserts that the density of a packing of congruent spheres in three dimensions is never greater than $π/\sqrt{18}\approx 0.74048...$. This is the oldest problem in discrete geometry and is an important part of Hilbert&#39;s 18th problem. An example of a packing achieving t

Thomas C. Hales

This is the fifth in a series of papers giving a proof of the Kepler conjecture, which asserts that the density of a packing of congruent spheres in three dimensions is never greater than $π/\sqrt{18}\approx 0.74048...$. This is the oldest problem in discrete geometry and is an important part of Hilbert&#39;s 18th problem. An example of a packing achieving t

Samuel P. Ferguson, Thomas C. Hales

This is the second in a series of papers giving a proof of the Kepler conjecture, which asserts that the density of a packing of congruent spheres in three dimensions is never greater than $π/\sqrt{18}\approx 0.74048...$. This is the oldest problem in discrete geometry and is an important part of Hilbert&#39;s 18th problem. An example of a packing achieving

Thomas C. Hales

This is the first in a series of papers giving a proof of the Kepler conjecture, which asserts that the density of a packing of congruent spheres in three dimensions is never greater than $π/\sqrt{18}\approx 0.74048...$. This is the oldest problem in discrete geometry and is an important part of Hilbert&#39;s 18th problem. An example of a packing achieving t

A. Evdokimov, S. Kitaev

We introduced the notation of a set of prohibitions and give definitions of a complete set and a crucial word with respect to a given set of prohibitions. We consider 3 particular sets which appear in different areas of mathematics and for each of them examine the length of a crucial word. One of these sets is proved to be incomplete. The problem of determin

Sergey Kitaev

Berstel proved that the Arshon sequence cannot be obtained by iteration of a morphism. An alternative proof of this fact is given here. The $σ$-sequence was constructed by Evdokimov in order to construct chains of maximal length in the n-dimensional unit cube. It turns out that the $σ$-sequence has a close connection to the Dragon curve. We prove that the $σ

Sergey Kitaev

Babson and Steingr\&#39;ımsson introduced generalized permutation patterns that allow the requirement that two adjacent letters in a pattern must be adjacent in the permutation. We consider n-permutations that avoid the generalized pattern 1-32 and whose k rightmost letters form an increasing subword. The number of such permutations is a linear combination o

James McKernan

We prove a conjecture of Batryev which states that the family of all Fano varieties with kawamata log terminal singularities and fixed index, forms a bounded family.

Xiaotao Sun, Sheng-Li Tan, Kang Zuo

Let $f:X\to C$ be a family of semistable K3 surfaces with non-empty set $S$ of singular fibres having infinite local monodromy. Then, when the so called Arakelov-Yau inequality reaches equality, we prove that $C\setminus S$ is a modular curve and the family comes essentially from a family of elliptic curves through a so called Nikulin-Kummer construction. In

J. Donin

We give a classification of polarized deformation quantizations on a symplectic manifold with a (complex) polarization. Also, we establish a formula which relates the characteristic class of a polarized deformation quantization to its Fedosov class and the Chern class of the polarization.

Misha Verbitsky

Let M be a K3 surface or an even-dimensional compact torus. We show that the category of coherent sheaves on M is independent from the choice of the complex structure, if this complex structure is generic.

Olga Radko

Poisson structures vanishing linearly on a set of smooth closed disjoint curves are generic in the set of all Poisson structures on a compact connected oriented surface. We construct a complete set of invariants classifying these structures up to an orientation-preserving Poisson isomorphism. We show that there is a set of non-trivial infinitesimal deformati

A. N. Panov

There studed correspondence between symplectic leaves, irreducible representations and prime ideals, which is invariant with respect to quantum adjoint action. The Conjecture of De Concini-Kac-Procesi on dimensions of irreducible representations is proved for sufficiently great $l$.

Martin Rubey

Based on Schützenberger&#39;s evacuation and a modification of jeu de taquin, we give a bijective proof of an identity connecting the generating function of reverse semistandard Young tableaux with bounded entries with the generating function of all semistandard Young tableaux. This solves Exercise 7.102 b of Richard Stanley&#39;s book `Enumerative Combinato

Dan N. Vollick

One of the most intriguing unsolved problems in modern cosmology involves the nature of the observed dark matter in the universe. Various hypothetical particles have been postulated as the source of the dark matter, but as of yet none of these particles have been observed. In this paper I present an alternative view. The observations indicate the presence of

Elcio Abdalla, Adenauer Casali, Bertha Cuadros-Melgar

We consider a six dimensional brane world model with asymmetric warp factors for time and both extra spatial coordinates, $y$ and $z$. We derive the set of differential equations governing the shortest graviton path and numerically solve it for AdS-Schwarzschild and AdS-Reissner-Nordström bulks. In both cases we derive a set of conditions for the existence o

A. Mironov

Integrability in string/field theories is known to emerge when considering dynamics in the moduli space of physical theories. This implies that one has to look at the dynamics with respect to unusual time variables like coupling constants or other quantities parameterizing configuration space of physical theories. The dynamics given by variations of coupling

Nicholas P. Warner

This is a slightly expanded version of my talk at Future Perspectives in Theoretical Physics and Cosmology, Stephen Hawking&#39;s 60th Birthday Worshop. I describe some of the issues that were important in gauged supergravity in the 1980&#39;s and how these, and related issues have once again become important in the study of holographic field theories.

Athanasios Prikas

We present the formalism of q-stars with local or global U(1) symmetry. The equations we formulate are solved numerically and provide the main features of the soliton star. We study its behavior when the symmetry is local in contrast to the global case. A general result is that the soliton remains stable and does not decay into free particles and the electro

Chang-Yeong Lee

We apply the method of algebraic deformation to N-tuple of algebraic K3 surfaces. When N=3, we show that the deformed triplet of algebraic K3 surfaces exhibits a deformed hyperkähler structure. The deformation moduli space of this family of noncommutatively deformed K3 surfaces turns out to be of dimension 57, which is three times of that of complex deformat

Leonid Frankfurt, Mark Strikman

We argue that the t-dependence of the two-gluon form factor of the nucleon should be given by $Γ(t)=(1-t/m_{2g}^2)^{-2}$ with $m_{2g}^2\approx 1 GeV^2$. We demonstrate that this form provides a good description of the t-dependence of the cross section of the elastic photoproduction of $J/ψ$-mesons between the threshold region of $E_γ=11 GeV$ (Cornell), $E_γ=

Tomislav Prokopec

After a short review of electroweak scale baryogenesis, we consider the dynamics of chiral fermions coupled to a complex scalar field through the standard Yukawa interaction term at a strongly first order electroweak phase transition. By performing a systematic gradient expansion we can use this simple model to study electroweak scale baryogenesis. We show t

Dariusz Prorok

A model for $J/Ψ$ suppression at a high energy heavy ion collision is presented. The main (and the only) reason for the suppression is $J/Ψ$ inelastic scattering within hadron matter. The hadron matter is in the form of an evolving multi-component point-like non-interacting gas. The estimations of the sound velocity in the gas and the approximate pattern of