December 2002 arXiv papers — page 17

R. M. Godbole, S. D. Rindani, R. K. Singh

We present results of an investigation to study CP violation in the Higgs sector in $t\bar t$ production at a $γγ$-collider. This is done in a model independent way in terms of six form-factors $\{\Re(S_γ), \Im(S_γ), \Re(P_γ), \Im(P_γ), S_t, P_t\}$ which parameterize the CP mixing in Higgs sector. The angular distribution of the decay lepton from $t/\bar t$

R. F. Wagenbrunn, S. Boffi, L. Ya. Glozman, W. Klink

Results for the proton and neutron electric and magnetic form factors as well as the nucleon axial form factor are presented for constituent quark models, based on either one-gluon-exchange and Goldstone-boson-exchange dynamics. The calculations are performed in a covariant framework using the point-form approach to relativistic quantum mechanics. The only i

T. M. Aliev, I. Kanik, A. Ozpineci

The coupling constant of rho --> eta gamma decay is calculated in the framework of light cone QCD sum rules. A comparison of our prediction on the coupling constant with the result obtained from analysis of the experimental data is performed.

M. A. Braun, C. Merino, G. Rodriguez

Strong correlations are obtained between the number and the average transverse momentum of jets emitted by the exchange of a single BFKL Pomeron.

F. J. Llanes-Estrada, A. Dobado, A. Gomez Nicola, J. R. Pelaez

We present our recent results for the rho and sigma mesons considered as resonances in pion-pion scattering in a thermal bath. We use chiral perturbation theory to fourth order in p for the low energy behaviour, then extend the analysis via the unitarization method of the Inverse Amplitude into the resonance region. The width of the rho broadens about twice

Felipe J. Llanes-Estrada, Pedro Bicudo

We briefly report on a relativistic quark model scheme to calculate the O(P^4) pion-pion vertex in the planar approximation and in the chiral limit. The calculation is reduced to the solution of simple integral equations (Bethe-Salpeter like) by an effective use of chiral Ward Identities. Specific model computations are provided.

Howard E. Haber

A short review of the theory and phenomenology of Higgs bosons is given, with focus on the Standard Model (SM) and the minimal supersymmetric extension of the Standard Model (MSSM). The potential for Higgs boson discovery at the Tevatron and LHC, and precision Higgs studies at the LHC and a future e+e- linear collider are briefly surveyed. The phenomenologic

Antonios Papazoglou

In this thesis, we discuss the idea of multigravity, namely the possibility that a significant component of gravity that we feel at intermediate distances (1 mm < r < 10^26 cm) is due to massive but ultralight gravitons. We demonstrate how this phenomenon can be realized in brane-world models in a spacetime with more than four dimensions and discuss how modi

Shinji Ejiri

We comment on the reweighting method in the chemical potential $(μ_{\rm q})$ direction. We study the fluctuation of the reweighting factor during Monte-Carlo steps. We find that it is the absolute value of the reweighting factor that mainly contributes to the shift of the phase transition line $(β_c)$ by the presence of $μ_{\rm q}$. The phase fluctuation is

Werner Kerler

We only require generalized chiral symmetry and $γ_5$-hermiticity, which leads to a large class of Dirac operators describing massless fermions on the lattice, and use this framework to give an overview of developments in this field. Spectral representations turn out to be a powerful tool for obtaining detailed properties of the operators and a general const

Xianfeng Gu, Shing-Tung Yau

This paper solves the problem of computing conformal structures of general 2-manifolds represented as triangle meshes. We compute conformal structures in the following way: first compute homology bases from simplicial complex structures, then construct dual cohomology bases and diffuse them to harmonic 1-forms. Next, we construct bases of holomorphic differe

Daniel L. Blair, A. Kudrolli

We present an experimental investigation of the statistical properties of spherical granular particles on an inclined plane that are excited by an oscillating side-wall. The data is obtained by high-speed imaging and particle tracking techniques. We identify all particles in the system and link their positions to form trajectories over long times. Thus, we i

Y. Martinez-Raton

I study the effect of length polydispersity in the surface phase diagram of hard rods interacting with a hard wall. The properly extended interface Gibbs-Duhem equation for a polydisperse system allows us to predict the behaviour of the surface tension as a function of the bulk density at the the wall-isotropic interface. Two groups of qualitative different

J. Ranninger, L. Tripodi

The change-over from phase- to amplitude-fluctuation driven superconductivity is examined for a composite system of free electrons (Fermions with concentration n_F) and localized electron-pairs (hard-core Bosons with concentration n_B) as a function of doping-changing n_B. The coupling together of these two subsystems via a charge exchange term induces elect

J. Myslivecek, C. Schelling, F. Schaffler, G. Springholz

Scanning tunneling microscopy experiments show that the unstable growth morphology observed during molecular beam homoepitaxy on slightly vicinal Si(001) surfaces consists of straight step bunches. The instability occurs under step- flow growth conditions and vanishes both during low-temperature island growth and at high temperatures. An instability with the

K. Mallick, P. Marcq

We study analytically and numerically the problem of a nonlinear mechanical oscillator with additive noise in the absence of damping. We show that the amplitude, the velocity and the energy of the oscillator grow algebraically with time. For Gaussian white noise, an analytical expression for the probability distribution function of the energy is obtained in

B. W. Hoogenboom, C. Berthod, M. Peter, Ø. Fischer

Recent angle-resolved photoemission and neutron scattering data have provided new ingredients for the interpretation of scanning tunneling spectra on Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$. We analyze the low-temperature tunneling spectra, from oxygen overdoped to underdoped samples, including details about the bilayer splitting and the neutron resonance peak. Two va

F. Aliotta, G. Di Marco, R. Ober, M. Pieruccini

The effects of a (non co-crystallizing) nucleating agent on secondary nucleation rate and final lamellar thickness in isothermally melt-crystallizing polyethylene oxide are considered. SAXS reveals that lamellae formed in nucleated samples are thinner than in the pure samples crystallized at the same undercoolings. These results are in quantitative agreement

Go Kato, Miki Wadati

Thermodynamics of the XXX Heisenberg model is studied. The trace of the Boltzmann weight with respect to the Hilbert space is taken in the thermodynamic limit with the number of up-spins being fixed. The expression of the trace gives an explanation why the correct thermodynamic quantities are derived from the string hypothesis. Combining this with the previo

Go Kato, Miki Wadati

The XXX Heisenberg model is studied at finite temperature. The free energy is derived without recourse to Thermal Bethe Ansatz method and Quantum Transfer Matrix method. The result perfectly agrees with the free energy derived by Thermal Bethe Ansatz method. An explicit expression of the cluster expansion coefficient in arbitrary order is presented for the f

A. O. Parry, M. J. Greenall, J. M. Romero-Enrique

Critical wetting is an elusive phenomenon for solid-fluid interfaces. Using interfacial models we show that the diverging length scales, which characterize complete wetting at an apex, precisely mimic critical wetting with the apex angle behaving as the contact angle. Transfer matrix, renormalization group (RG) and mean field analysis (MF) shows this covaria

Go Kato, Miki Wadati

One-dimensional repulsive delta-function bose system is studied. By only using the Bethe ansatz equation, n-particle partition functions are exactly calculated. From this expression for the n-particle partition function, the n-particle cluster integral is derived. The results completely agree with those of the thermal Bethe ansatz (TBA). This directly proves

Go Kato, Miki Wadati

The N-particle partition function of a one-dimensional $δ$-function bose gas is calculated explicitly using only the periodic boundary condition (the Bethe ansatz equation). The N-particles cluster integrals are shown to be the same as those by the thermal Bethe ansatz method.

Roland R. Netz, Henri Orland

We apply general variational techniques to the problem of the counterion distribution around highly charged objects where strong condensation of counterions takes place. Within a field-theoretic formulation using a fluctuating electrostatic potential, the concept of surface-charge renormalization is recovered within a simple one-parameter variational procedu

C. Grimaldi, T. Maeder, P. Ryser, S. Straessler

We re-analyse earlier measurements of resistance R and piezoresistance K in RuO2-based thick-film resistors. The percolating nature of transport in these systems is well accounted by values of the transport exponent t larger than its universal value t=2.0. Furthermore, we show that the RuO2 volume fraction dependence of the piezoresistance data fit well with

M. Patriarca, M. Robles, K. Kaski

We show that a microscopic definition of crystal defect, based on the effective mean single-particle potential energy, makes it possible to detect and visualize various types of local and extended crystal defects and develop an effective algorithm for tracking their time evolution.

S. Takahashi, S. Maekawa

We study theoretically the spin transport in a nonmagnetic metal connected to ferromagnetic injector and detector electrodes. We derive a general expression for the spin accumulation signal which covers from the metallic to the tunneling regime. This enables us to discuss recent controversy on spin injection and detection experiments. Extending the result to

Thorsten Emig, Simon Bogner

The criteria for the existence of a glass transition in a planar vortex array with quenched disorder are studied. Applying a replica Bethe ansatz, we obtain for self-avoiding vortices the exact quenched average free energy and effective stiffness which is found to be in excellent agreement with recent numerical results for the related random bond dimer model

Leo Radzihovsky, Noel A. Clark

We point out that the phenomenon ``heating by freezing&#39;&#39; discovered in nonequilibrium simulations by Helbing, et al. (PRL 84, 1240 (2000)) extends to equilibrium systems as well. We argue that such reentrant fluctuation-driven freezing can, for example, be realized in two-dimensional colloidal systems subjected to a one-dimensional periodic potential

Yu. A. Pashkin, T. Yamamoto, O. Astafiev, Y. Nakamura

Despite an apparent progress in implementing individual solid-state qubits, there have been no experimental reports so far on multi-bit gates required for building a real quantum computer. Here we report a new circuit comprising two coupled charge qubits. Using a pulse technique, we coherently mix quantum states and observe quantum oscillations whose spectru

E. Ben-Naim, P. L. Krapivsky, S. Redner

We study an opinion dynamics model in which agents reach compromise via pairwise interactions. When the opinions of two agents are sufficiently close, they both acquire the average of their initial opinions; otherwise, they do not interact. Generically, the system reaches a steady state with a finite number of isolated, noninteracting opinion clusters (``par

T. Mueller, K. -H. Heinig, W. Moeller

Kinetic 3D lattice Monte Carlo studies are presented on Si nanocrystal (NC) formation by phase separation in 1 keV Si implanted thin SiO2 films. The simulation start from Si depth profiles calculated using the dynamic, high-fluence binary collision code TRIDYN. From the initial Si supersaturation, NCs are found to form either by nucleation, growth and Ostwal

J. Gorosabel, L. Christensen, J. Hjorth, J. U. Fynbo

We present UBVRIZJsHKs broad band photometry of the host galaxy of the dark gamma-ray burst (GRB) of February 10, 2000. These observations represent the most exhaustive photometry given to date of any GRB host galaxy. A grid of spectral templates have been fitted to the Spectral Energy Distribution (SED) of the host. The derived photometric redshift is z=0.8

A. V. Zasov, D. V. Bizyaev

The relationship between the geometrical properties of stellar disks (a flatness and truncation radius) and the disk kinematics are considered for edge-on galaxies. It is shown that the observed thickness of the disks and the approximate constancy of their thickness along the radius well agrees with the condition of their marginal local gravitational stabili

Renato A. Dupke, Raymond E. White

We present the results of a spatially-resolved spectroscopic analysis of the galaxy cluster Abell 496 with the S3 chip on-board the Chandra satellite. We confirm the presence of a central positive temperature gradient consistent with a cooling flow, but with a minimum gas temperature of ~0.5-0.9 keV. The cluster also exhibits sharp edges in gas density and t

C. C. Cheung, J. F. C. Wardle, Tingdong Chen, S. P. Hariton

We report initial results from the detection of optical emission in the arcsecond-scale radio jets of two quasars utilizing images from the {\it Hubble Space Telescope} archive. The optical emission has a very knotty appearance and is consistent with synchrotron emission from highly relativistic electrons in the jet. Combining these observations with those o

A. Meli, J. J. Quenby

We perform Monte Carlo simulations of diffusive shock acceleration at highly relativistic oblique shock waves. High upstream flow Lorentz gamma factors are used, which are relevant to models of ultra relativistic particle shock acceleration in Active Galactic Nuclei (AGN) central engines and relativistic jets and Gamma Ray Burst (GRB) fireballs. We investiga

A. Meli, J. J Quenby

Monte-Carlo computations for highly relativistic parallel shock particle acceleration are presented for upstream flow gamma factors, $Γ=(1-V_{1}^{2}/c^{2})^{-0.5}$ with values between 5 and $10^{3}$. The results show that the spectral shape at the shock depends on whether or not the particle scattering is small angle with $δθ< Γ^{-1}$ or large angle, which i

G. Hütsi, J. Einasto, D. L. Tucker, E. Saar

The luminosity function of galaxies of the Early Data Release of the Sloan Digital Sky Survey (SDSS) and the Las Campanas Redshift Survey (LCRS) is calculated. The luminosity function depends on redshift, density of the environment and is different for the Norther and Southern slice of SDSS. Luminosity functions is used to derive the number and luminosity de

Fabrizio Tavecchio

The Chandra discovery of bright X-ray emission from kpc-scale jets provides us unprecedented insights into the physical state of the plasma in the flow. In particular it is possible to get good constraints on the power and pressure in bright knots. For a group of selected sources with blazar-type cores it is also possible to constrain the physical quantities

F. F. S. van der Tak, A. M. S. Boonman, R. Braakman, E. F. van Dishoeck

We present submillimeter observations of SO, SO2, H2S, H2CS, OCS, NS and HCS+ toward nine massive young stars. The outflow contributes ~50% to the SO and SO2 emission in 15-20&#39;&#39; beams, more than for CS, where it is 10%. The SO2 abundance increases from dark cloud levels in the outer envelope (T<100 K) to levels seen in hot cores and shocks in the inn

Floris F. S. van der Tak, Dariusz C. Lis, Maryvonne Gerin, Evelyne Roueff

Research on interstellar ND3 is reviewed and updated from the discovery papers. Results from observations of a dozen sources at centimeter and submillimeter wavelengths are presented. The two data sets are consistent, but do not constrain the excitation conditions in the ND3-emitting gas. The column density ratios of NH3:NH2D, NH2D:ND2H and ND2H:ND3, observe

R. Morganti, T. A. Oosterloo, A. Capetti, H. R. de Ruiter

We present WSRT observations of the neutral hydrogen in the nearby radio galaxy B2 0648+27. In emission, we detect a very large amount of HI (M_HI = 1.1 x 10^10 M_sun) that is distributed in a very extended disk, or ring-like structure, of about 160 kpc in size. We also detect HI absorption against the central radio continuum component. The detection of the

R. Morganti, C. Tadhunter, T. Oosterloo, J. Holt

The study of both neutral and ionized gas in young radio sources is providing key information on the effect the radio plasma has on the ISM of these objects. We present results obtained for the compact radio sources PKS1549-79, 4C12.50 and PKS1814-63 and for the intermediate-size radio galaxy 3C459. At least in the first two, low ionisation optical emission

Daniel Pfenniger

To understand galaxies and their evolution, it is necessary to describe how the different scales interact: how the microscopic physics, such as star formation, or the large scale physics, such as galaxy interactions may modify the galaxy global shapes. The purpose of this review is to point out some general or recent topics related to such scale interactions

F. Haberl, K. Dennerl, W. Pietsch

First results from a deep XMM-Newton observation of a field in the Large Magellanic Cloud (LMC) near the northern rim of the supergiant shell LMC 4 are presented. Spectral and temporal analyses of a sample of selected X-ray sources yielded two new candidates for supernova remnants, a supersoft X-ray source and a likely high mass X-ray binary (HMXB) pulsar. F

K. G. Noeske, P. Papaderos, L. M. Cairos, K. J. Fricke

We present deep Near-Infrared (NIR) imaging of Blue Compact Dwarf Galaxies (BCDs), allowing for the first time to derive and systematize the NIR structural properties of their stellar low-surface brightness (LSB) host galaxies. Compared to optical data, NIR images, being less contamined by the extended stellar and ionized gas emission from the starburst, per

H. -Th. Janka, R. Buras, M. Rampp

We present here the first results of two-dimensional hydrodynamical simulations of the neutrino-heating phase in the collapsed core of a 15 solar mass star, where the neutrino transport is treated with a variable Eddington factor method for solving the Boltzmann transport equation, and the neutrino interactions include nucleon-nucleon bremsstrahlung, nucleon

H. -Th. Janka, R. Buras, K. Kifonidis, T. Plewa

The rapidly growing base of observational data for supernova explosions of massive stars demands theoretical explanations. Central of these is a self-consistent model for the physical mechanism that provides the energy to start and drive the disruption of the star. We give arguments why the delayed neutrino-heating mechanism should still be regarded as the s

F. De Paolis, G. Ingrosso, A. A. Nucita, D. Orlando

Observations with the Extreme UltraViolet Explorer (EUVE) satellite have shown that the inner region of the Virgo cluster (centered in M87 galaxy) has a strong Extreme UltraViolet (EUV) emission (up to $13^{\prime}$) in excess to the low-energy tail expected from the hot, diffuse IntraCluster Medium (ICM). Detailed observations of large scale radio emission

Roban H. Kramer, Stephanie K. Tonnesen, David H. Cohen, Stanley P. Owocki

The launch of high-spectral-resolution x-ray telescopes (Chandra, XMM) has provided a host of new spectral line diagnostics for the astrophysics community. In this paper we discuss Doppler-broadened emission line profiles from highly supersonic outflows of massive stars. These outflows, or winds, are driven by radiation pressure and carry a tremendous amount

J. Einasto, G. H&#34;utsi, M. Einasto, E. Saar

Two-dimensional high-resolution density field of galaxies of the Early Data Release of the Sloan Digital Sky Survey with a smoothing lengths 0.8 h^{-1} Mpc is applied to extract clusters of galaxies, and a low-resolution field with smoothing lengths 10^{-1} Mpc to extract superclusters of galaxies. We compare properties of density field clusters and superclu

Licia Verde, Alan F. Heavens, Will J. Percival, Sabino Matarrese

By studying the bispectrum of the galaxy distribution in the 2dF galaxy redhsift survey (2dFGRS), we have shown that 2dFGRS galaxies are unbiased tracers of the mass distribution. This allows us the break the degeneracy intrinsic to power spectrum studies, between the matter density parameter Omega_m and the bias parameter b, and to obtain an accurate measur

S. Peng Oh, Andrew Benson

Both preheating of the intergalactic medium and radiative cooling of low entropy gas have been proposed to explain the deviation from self-similarity in the cluster L_x-T_x relation and the observed entropy floor in these systems. However, severe overcooling of gas in groups is necessary for radiative cooling alone to explain the observations. Non-gravitatio

D. S. Hudson, M. J. Henriksen, S. Colafrancesco

We present an analysis of BeppoSAX observations of the IC1262 galaxy cluster and report the first temperature and abundance measurements, along with preliminary indications of diffuse, nonthermal emission. By fitting a 6&#39; (~360 h_50^-1 kpc) region with a single Mewe-Kaastra-Liedahl model with photoelectric absorption, we find a temperature of 2.1 - 2.3 k

M. Mueller, K. Katsov, M. Schick

We have carried out extensive Monte Carlo simulations of the fusion of tense apposed bilayers formed by amphiphilic molecules within the framework of a coarse grained lattice model. The fusion pathway differs from the usual stalk mechanism. Stalks do form between the apposed bilayers, but rather than expand radially to form an axial-symmetric hemifusion diap

Amit Loewy, Yaron Oz

We consider strings with large spin in AdS_3xS^3xM with NS-NS background. We construct the string configurations as solutions of SL(2,R) WZW theory. We compute the relation between the space-time energy and spin, and show that the anomalous correction is constant, and not logarithmic in the spin. This is in contrast to the S-dual background with R-R charge w

Roni Harnik, Daniel T. Larson, Hitoshi Murayama, Aaron Pierce

The large observed mixing angle in atmospheric neutrinos, coupled with Grand Unification, motivates the search for a large mixing between right-handed strange and bottom squarks. Such mixing does not appear in the standard CKM phenomenology, but may induce significant b to s transitions through gluino diagrams. Working in the mass eigenbasis, we show quantit

G. Bhattacharyya, H. V. Klapdor-Kleingrothaus, H. Päs, A. Pilaftsis

We study the model-building conditions under which a sizeable $0νββ$-decay signal to the recently reported level of~0.4 eV is due to Kaluza--Klein singlet neutrinos in theories with large extra dimensions. Our analysis is based on 5-dimensional singlet-neutrino models compactified on an $S^1/Z_2$ orbifold, where the Standard--Model fields are localized on a

Axel de la Macorra

We study the possibility that a dark group, a gauge group with particles interacting with the standard model particles only via gravity, is responsible for containing the dark energy and dark matter required by present day observations. We show that it is indeed possible and we determine the constrains for the dark group. The non-perturbative effects generat

M. De Pasquale, L. Piro, R. Perna, E. Costa

We have examined the complete set of X-ray afterglow observations of dark and optically bright GRBs performed by BeppoSAX until February 2001. X-ray afterglows are detected in 90% of the cases. We do not find significant differences in the X-ray spectral shape, in particular no higher X-ray absorption in GRBs without optical transient (dark GRBs) compared to

Gregory Schehr, Thierry Giamarchi, Pierre Le Doussal

We study the thermodynamics of the vibrational modes of a lattice pinned by impurity disorder in the absence of topological defects (Bragg glass phase). Using a replica variational method we compute the specific heat $C_v$ in the quantum regime and find $C_v \propto T^3$ at low temperatures in dimension three and two. The prefactor is controlled by the pinni

Jason Kumar, Arvind Rajaraman

We find explicit supergravity solutions which describe branes in the AdS_3 x S^3 background. These solutions preserve 8 of the 16 supersymmetries of this background, and are consistent with kappa-symmetry. These represent new 1/2-BPS states of string theory.

D. J. Wineland, M. Barrett, J. Britton, J. Chiaverini

Experiments directed towards the development of a quantum computer based on trapped atomic ions are described briefly. We discuss the implementation of single qubit operations and gates between qubits. A geometric phase gate between two ion qubits is described. Limitations of the trapped-ion method such as those caused by Stark shifts and spontaneous emissio

Raul Rabadan, Gary Shiu

Compactifying a higher-dimensional theory defined in R^{1,3+n} on an n-dimensional manifold {\cal M} results in a spectrum of four-dimensional (bosonic) fields with masses m^2_i = λ_i, where - λ_i are the eigenvalues of the Laplacian on the compact manifold. The question we address in this paper is the inverse: given the masses of the Kaluza-Klein fields in

Katsuhiro Nishinari, Martin Treiber, Dirk Helbing

Based on the statistical evaluation of experimental single-vehicle data, we propose a quantitative interpretation of the erratic scattering of flow-density data in synchronized traffic flows. A correlation analysis suggests that the dynamical flow-density data are well compatible with the so-called jam line characterizing fully developed traffic jams, if one

V. P. Goncalves, M. V. T. Machado

The contribution of the QCD Pomeron to the process AA -> AA J/Psi J/Psi is discussed. We focus on the photon-photon collision, with the quasi-real photon coming from the Weizsacker - Williams spectrum of the nuclei. We calculate the cross section for this process considering the solution of the LLA BFKL equation at zero momentum transfer using a small-t appr

Qing-feng Sun, Hong Guo, Jian Wang

We propose and investigate a spin-cell device which provides the necessary spin-motive force to drive a spin current for future spintronic circuits. Our spin-cell have four basic characteristics: (i) it has two poles so that a spin current flows in from one pole and out from the other pole, this way a complete spin-circuit can be established; (ii) it has a s

F. La Barbera, G. Busarello, P. Merluzzi, M. Massarotti

We study the evolution of the relation between half-light (effective) radius, r_e, and mean surface brightness, mi_e, known as Kormendy relation, out to redshift z=0.64 in V-band restframe on the basis of a large sample of spheroidal galaxies (N=228) belonging to three clusters of galaxies. The present sample constitutes the largest data set for which the Ko

A. Hebecker, A. Westphal

One of the much-debated novel features of theories with extra dimensions is the presence of power-like loop corrections to gauge coupling unification, which have the potential of allowing a significant reduction of the unification scale. A recognized problem of such scenarios is the UV sensitivity of the above power corrections. We consider situations where

Halvor Moll Nilsen, Dermot McPeake, J F McCann

The gyroscopic motion of a trapped Bose gas containing a vortex is studied. We model the system as a classical top, as a superposition of coherent hydrodynamic states, by solution of the Bogoliubov equations, and by integration of the time-dependent Gross-Pitaevskii equation. The frequency spectrum of Bogoliubov excitations, including quantum frequency shift

N. Kidonakis, E. Laenen, S. Moch, R. Vogt

We describe calculations of $c \bar c$ production to next-to-next-to-leading order (NNLO) and next-to-next-to-leading logarithm (NNLL) near threshold in $pp$ and $π^- p$ interactions. We study the relevance of these calculations for existing $c \bar c$ total cross section data by examining their sensitivity to partonic threshold kinematics, their convergence

Pau Amaro-Seoane, Rainer Spurzem

In the 60s and 70s super-massive central objects (from now onwards SMOs) were thought to be the main source of active galactic nuclei (AGNs) characteristics (luminosities of $L \approx 10^{12} L_{\odot}$). The release of gravitational binding energy by the accretion of material on to an SMO in the range of $10^7 - 10^9 M_{\odot}$ has been suggested to be the

J. Slivova

A study of differential elliptic event anisotropies (v_2) of charged particles and high-pt pions in 158 AGeV/c Pb+Au collisions is presented. Results from correlations with respect to the event plane and from two-particle azimuthal correlations are compared. The latter give systematically higher v_2 values at pt>1.2GeV/c providing possibly an evidence of a n

S. Bellucci, E. Ivanov, S. Krivonos

We explicitly construct N=1 worldvolume supersymmetric minimal off-shell Goldstone superfield actions for two options of 1/2 partial spontaneous breaking of AdS5 supersymmetry SU(2,2|1) corresponding to its nonlinear realizations in the supercosets with the AdS5 and AdS5 X S1 bosonic parts. The relevant Goldstone supermultiplets are comprised, respectively,

Gianluca Panati, Herbert Spohn, Stefan Teufel

We consider an electron moving in a periodic potential and subject to an additional slowly varying external electrostatic potential, $ϕ(\epsi x)$, and vector potential $A(\epsi x)$, with $x \in \R^d$ and $\epsi \ll 1$. We prove that associated to an isolated family of Bloch bands there exists an almost invariant subspace of $L^2(\R^d)$ and an effective Hamil

P. Fraundorf, W. Qin, Peter Moeck, Eric Mandell

The orientation-dependence of thin-crystal lattice fringes can be gracefully quantified using fringe-visibility maps, a direct-space analog of Kikuchi maps. As in navigation of reciprocal space with the aid of Kikuchi lines, fringe-visibility maps facilitate acquisition of 3D crystallographic information in lattice images. In particular, these maps can help

J. Ponce de Leon

We consider brane-world models embedded in a five-dimensional bulk spacetime with a large extra dimension and a cosmological constant. The cosmology in $5D$ possesses "wave-like" character in the sense that the metric coefficients in the bulk are assumed to have the form of plane waves propagating in the fifth dimension. We model the brane as the "plane" of

J. L. Charvet, R. Dayras, D. Durand, O. Lopez

A previous analysis of the charge (Z) correlations in the $ΔZ-<Z>$ plane for Xe+Sn central collisions at 32 MeV/u has shown an enhancement in the production of equally sized fragments (low $ΔZ$) which was interpreted as an evidence for spinodal decomposition. However the signal is weak and rises the question of the estimation of the uncorrelated yield. After

J. D. Edelstein, A. Paredes, A. V. Ramallo

We obtain a unified picture for the conifold singularity resolution. We propose that gauged supergravity, through a novel prescription for the twisting, provides an appropriate framework to smooth out singularities in the context of gravity duals of supersymmetric gauge theories.

N. G. Parker, N. P. Proukakis, M. Leadbeater, C. S. Adams

Longitudinal confinement of dark solitons in quasi-one-dimensional Bose-Einstein condensates leads to sound emission and reabsorption. We perform quantitative studies of the dynamics of a soliton oscillating in a tight dimple trap, embedded in a weaker harmonic trap. The dimple depth provides a sensitive handle to control the soliton-sound interaction. In th

A. A. Andrianov, V. A. Andrianov, S. S. Afonin

The relations between masses and decay constants of variety of meson resonances in the energy range 0--3 GeV are verified from the string-like, linear mass spectrum for vector, axial-vector, scalar and pseudoscalar mesons with a universal slope. The way to match the universality with the Operator Product Expansion (OPE) is proposed. The necessity of small de

Tanwi Ghosh, P. Mitra

Dilaton black hole solutions which are neither asymptotically flat nor (anti)-de Sitter but reduce to asymptotically flat solutions in some special limits have been known for a Liouville type dilatonic potential. It is shown how, by solving a pair of coupled differential equations, infinitesimally small angular momentum can be added to these static solutions

E. Kojima, R. Shimano, Y. Hashimoto, S. Katsumoto

The dynamics of magnetization under femtosecond optical excitation is studied in a ferromagnetic semiconductor Ga_{0.94}Mn_{0.06}As with a time-resolved magneto-optical Kerr effect measurement with two color probe beams. The transient reflectivity change indicates the rapid rise of the carrier temperature and relaxation to a quasi-thermal equilibrium within

J. Loeffelholz, G. Morchio, F. Strocchi

The mathematical structure of the temporal gauge of QED is critically examined in both the alternative formulations characterized by either positivity or regularity of the Weyl algebra. The conflict between time translation invariance and Gauss law constraint is shown to lead to peculiar features. In the positive case only the correlations of exponentials of

P. Dolan, A. Gerber

Using the work by Bampi and Caviglia, we write the Weyl-Lanczos equations as an exterior differential system. Using Janet-Riquier theory, we compute the Cartan characters for all spacetimes with a diagonal metric and for the plane wave spacetime since all spacetimes have a plane wave limit. We write the Lanczos wave equation as an exterior differential syste

A. Y. Abul-Magd, H. L. Harney, M. H. Simbel, H. A. Weidenmueller

We consider nearest neighbor spacing distributions of composite ensembles of levels. These are obtained by combining independently unfolded sequences of levels containing only few levels each. Two problems arise in the spectral analysis of such data. One problem lies in fitting the nearest neighbor spacing distribution to the histogram of level spacings obta

Mamoru Shimizu, Tetsu Kitayama, Shin Sasaki, Yasushi Suto

We derive constraints on the mass-temperature relation of galaxy clusters from their observed luminosity-temperature relation and X-ray temperature function. Adopting the isothermal gas in hydrostatic equilibrium embedded in the universal density profile of dark matter halos, we compute the X-ray luminosity for clusters as a function of their hosting halo ma

Manasse R. Mbonye

The early cosmic inflation, when taken along with the recent observations that the universe is currently dominated by a low density vacuum energy, leads to at least two potential problems which modern cosmology must address. First, there is the old cosmological constant problem, with a new twist: the coincidence problem. Secondly, cosmology still lacks a mod

Naoyuki Haba, Yasuhiro Shimizu

We consider 5 dimensional E_6 and E_7 supersymmetric grand unified theories (GUTs) on an orbifold S^1/Z_2, in which the Higgs fields arise from the 5th components of the 5D gauge fields. We introduce matter fields in 5 dimensions, then the Yukawa interactions are induced from the gauge interactions among the 5th component of gauge fields and the bulk hyper-m

Steven S. Gubser, Igor R. Klebanov

We study large N conformal field theories perturbed by relevant double-trace deformations. Using the auxiliary field trick, or Hubbard-Stratonovich transformation, we show that in the infrared the theory flows to another CFT. The generating functionals of planar correlators in the ultraviolet and infrared CFT&#39;s are shown to be related by a Legendre trans

Stefano Bianco

Using the FOCUS spectrometer (experiments 687 and 831 at Fermilab) we confirm the existence of a diffractively photoproduced enhancement in $K^+K^- $ at 1750 \mevcc with nearly 100 times the statistics of previous experiments. We also observe a narrow dip structure at 1.9 GeV/c$^2$ in a study of diffractive photoproduction of the $3π^+3π^-$ final state.

Ian I. Kogan, Dimitri Polyakov

Brane-like vertex operators, defining backgrounds with the ghost-matter mixing in NSR superstring theory, play an important role in a world-sheet formulation of D-branes and M theory, being creation operators for extended objects in the second quantized formalism. In this paper we show that dilaton&#39;s beta function in ghost-matter mixing backgrounds becom

Robert Garisto

We study the apparent nonlocality of quantum mechanics as a transport problem. If space is a physical entity through which quantum information (QI) must be transported, then one can define its speed. If not, QI exists apart from space, making space in some sense `nonphysical&#39;. But we can still assign a `speed&#39; of QI to such models based on their prop

J. Casahorran

We study the quantum-mechanical tunneling phenomenon in models which include the existence of non-equivalent vacua. For such a purpose we evaluate the euclidean propagator between two minima of the potential at issue in terms of the quadratic fluctuations over the corresponding instantons. The effect of the multi-instanton configurations are included by mean

V. Druzhinina, M. DeKieviet

We present first experimental data on the high energy behavior of helium atoms quantum reflecting from the nanoscopically disordered surface of a quartz crystal. The use of the light, stable and inert He atom not only opens the unique possibility of measuring quantum reflectivity in the thusfar inaccessible limit of high energies, but also allows the determi

L. Samaj

We introduce a new class of quantum models with time-dependent Hamiltonians of a special scaling form. By using a couple of time-dependent unitary transformations, the time evolution of these models is expressed in terms of related systems with time-independent Hamiltonians. The mapping of dynamics can be performed in any dimension, for an arbitrary number o

M. Fernandez Guasti, H. Moya-Cessa

The correspondence between classical and quantum invariants is established. The Ermakov Lewis quantum invariant of the time dependent harmonic oscillator is translated from the coordinate and momentum operators into amplitude and phase operators. In doing so, Turski&#39;s phase operator as well as Susskind-Glogower operators are generalized to the time depen

Gustavo Homem

Abreu, R. suggested a new interpretation for the Lorentz Transformation (LT), a different LT derivation and a new &#34;synchronized&#34; space time transformation (ST). While he has shown that his results could be expressed in a Lorentz invariant form, the simplest (but perhaps most shocking) approach appears to be the use of the ST. The simplicity of this f

Rodrigo de Abreu

Temperature is introduced as a derived concept from energy and entropy. We consider two sub-systems in equilibrium for several configurations. The equality of temperature of the sub-systems is obtained from the equilibrium condition. The isothermal transformation is defined for several configurations and from this definition we obtain the Clausius-Clapeyron