March 2003 arXiv papers — page 8

A. V. Kuznetsov, N. V. Mikheev, D. A. Rumyantsev

A general analysis of the n-vertex loop amplitude in a strong magnetic field is performed, based on the asymptotic form of the electron propagator in the field. As an example, the photon-neutrino processes are considered, where one vertex in the amplitude is of a general type, and the other vertices are of the vector type. It is shown, that for odd numbers o

Jonathan L. Rosner

Recent results obtained from B decays on the phases of weak couplings described by the Cabibbo-Kobayashi-Maskawa (CKM) matrix are discussed, with particular emphasis on $α$ and $γ= π- β- α$.

Irina Dymnikova, Alexander Sakharov, Juergen Ulbricht, Jiawei Zhao

We review the experimental limits on those hypothetical interactions where the fundamental particles could exhibit non point-like behavior. In particular we have focused on the QED reaction measuring the differential cross sections for the process $ \EEGG $ at energies around 91 GeV and 209 GeV with data collected from the L3 detector from 1991 to 2001. With

F. Karsch, E. Laermann, P. Petreczky, S. Stickan

We analyze the cut-off dependence of mesonic spectral functions calculated at finite temperature on Euclidean lattices with finite temporal extent. In the infinite temperature limit we present analytic results for lattice spectral functions calculated with standard Wilson fermions as well as a truncated perfect action. We explicitly determine the influence o

Jesse Carlsson, Bruce H. J. McKellar

We calculate the masses of the lowest lying eigenstates of improved SU(2), SU(3), SU(4) and SU(5) Hamiltonian lattice gauge theory (LGT) in 2+1 dimensions using an analytic variational approach. The ground state is approximated by a one plaquette trial state and mass gaps are calculated in the symmetric and antisymmetric sectors by minimising over a suitable

The BABAR Collaboration, B. Aubert

We have performed a search for the decays $B^+\to J/ψp \barΛ$ and $B^0\to J/psi p \bar{p}$ in a data set of $(88.9 \pm 1.0)\times 10^6$ $Υ(4S)$ decays collected by the BaBar experiment at the PEP-II $\e^+e^-$ storage ring at the Stanford Linear Accelerator Center. Four charged $B$ candidates have been observed with an expected background of $0.21\pm 0.14$ ev

The OPAL collaboration

Non-commutative QED would lead to deviations from the Standard Model depending on a new energy scale Lambda_NC and a unique direction in space defined by two angles eta and xi. Here in this analysis eta is defined as the angle between the unique direction and the rotation axis of the earth. The predictions of such a theory for the process e+e- -> gamma gamma

J. Bicak, P. Krtous

The classical Bondi-Penrose approach to the gravitational radiation theory in asymptotically flat spacetimes is recalled and recent advances in the proofs of the existence of such spacetimes are briefly reviewed. We then mention the unique role of the boost-rotation symmetric spacetimes, representing uniformly accelerated objects, as the only explicit radiat

Rudi Cilibrasi, Paul Vitanyi, Ronald de Wolf

We present a fully automatic method for music classification, based only on compression of strings that represent the music pieces. The method uses no background knowledge about music whatsoever: it is completely general and can, without change, be used in different areas like linguistic classification and genomics. It is based on an ideal theory of the info

R. Andrew Hicks

We discuss design techniques for catadioptric sensors that realize given projections. In general, these problems do not have solutions, but approximate solutions may often be found that are visually acceptable. There are several methods to approach this problem, but here we focus on what we call the ``vector field approach''. An application is given

R. M. Gade

In this study, an integrable vertex model based on the quantum affine superalgebra $U_q\bigl(\hat{gl}(2|2)\bigr)$ is constructed. The model is characterized by a particular assignment of spectral parameters and lowest as well as highest weight $U_q\bigl(gl(2|2) \bigr)$ modules to its lattice links. Solutions of the corresponding intertwining conditions yield

Kerwin C. Foster, N. E. Bonesteel, Steven H. Simon

We develop a phenomenological description of the nu=5/2 quantum Hall state in which the Halperin-Lee-Read theory of the half-filled Landau level is combined with a p-wave pairing interaction between composite fermions (CFs). The electromagnetic response functions for the resulting mean-field superconducting state of the CFs are calculated and used in an RPA

A. J. Moreno, W. Kob

We present molecular dynamics simulations of the motion of a single rod in a two-dimensional random static array of disks. For long rods the mean-squared displacement of the center-of-mass shows a cage effect similar to that observed in supercooled liquids or dense colloidal systems. We have determined the time-dependence of the non-Gaussian parameter for di

M. Mancini, Ch. Oguey

In two dimensional foams at equilibrium, triangular bubbles can be freely exchanged with 3-fold stars --three edges ending at a central vertex. This theorem is deduced here from Moukarzel's duality. Moreover, to probe the method, a few related properties are established: under slow gas diffusion, T2 processes are continuous for triangles but not for othe

R. Mayol, M. Barranco, E. S. Hernandez, M. Pi

We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well defined surface and bulk regions together with a contact line, and they are structurally different from the well-known Andree

V. F. Gantmakher, S. N. Ermolov, G. E. Tsydynzhapov, A. A. Zhukov

Magnetotransport of superconducting Nd_{2-x}Ce_xCuO_{4+y} (NdCeCuO) films is studied in the temperature interval 0.3-30 K. The microscopic theory of the quantum corrections to conductivity, both in the Cooper and in the diffusion channels, qualitatively describes the main features of the experiment including the negative magnetoresistance in the high field l

S. Latil, S. Roche, A. Rubio

Persistent currents in rings constructed from carbon nanotubes are investigated theoretically. After studying the contribution of finite temperature or quenched disorder on covalent rings, the complexity due to the bundle packing is addressed. The case of interacting nanotori and self-interacting coiled nanotubes are analyzed in details in relation with expe

Mateu Llas, Pablo M. Gleiser, Albert Diaz-Guilera, Conrad J. Perez

In this work we study the interplay between the dynamics of a model of diffusion governed by a mechanism of imitation and its underlying structure. The dynamics of the model can be quantified by a macroscopic observable which permits the characterization of an optimal regime. We show that dynamics and underlying network cannot be considered as separated ingr

L. Falkovsky

The theory of Raman scattering by the electron--phonon coupled system in metals and heavily doped semiconductors is developed taking into account the Coulomb screening and the electron--phonon deformation interaction. The Boltzmann equation for carriers is applied. Phonon frequencies and optic coupling constants are renormalized due to interactions with carr

P. Süle

We analyze the superconducting state and c-axis charge dynamics of cuprates at optimal doping using a charge ordered bilayer superlattice model in which pairing is supported by inter-layer Coulomb energy gain (potential energy driven superconductivity).The 2D pair-condensate can be characterized by a charge ordered state with a "checkerboard" like pa

Yue Yu

We prove that the t-J-U model can be deduced from the Hubbard model at a large but finite U by a canonical transformation. We argue that the system may have a metal-insulator transition at a critical on-site Coulomb interaction whose value, however, is smaller than that in previous calculations in which the kinetic energy has a double counting. In a mean fie

M. Barranco, M. Guilleumas, E. S. Hernandez, R. Mayol

We investigate the spreading of 4He droplets on alkali surfaces at zero temperature, within the frame of Finite Range Density Functional theory. The equilibrium configurations of several 4He_N clusters and their asymptotic trend with increasing particle number N, which can be traced to the wetting behavior of the quantum fluid, are examined for nanoscopic dr

E. V. Deviatov, A. Wurtz, A. Lorke, M. Yu. Melnikov

Using a quasi-Corbino geometry to directly study electron transport between spin-split edge states, we find a pronounced hysteresis in the I-V curves, originating from slow relaxation processes. We attribute this long-time relaxation to the formation of a dynamic nuclear polarization near the sample edge. The determined characteristic relaxation times are 25

V. I. Yukalov

A physical system is called quasi-isolated if it subject to small random uncontrollable perturbations. Such a system is, in general, stochastically unstable. Moreover, its phase-space volume at asymptotically large time expands. This can be described by considering the local expansion exponent. Several examples illustrate that the stability indices and expan

S. Vasilyev, J. Jarvinen, A. I. Safonov, S. Jaakkola

We describe experiments where 2D atomic hydrogen gas is compressed thermally at a small "cold spot" on the surface of superfluid helium and detected directly with electron-spin resonance. We reach surface densities up to 5e12 1/cm^2 at temperatures of approximately 100 mK corresponding to the maximum 2D phase-space density of about 1.5. By independen

Yehiel Shilo, Ofer Biham

Abelian sandpile models, both deterministic, such as the Bak, Tang, Wiesenfeld (BTW) model [P. Bak, C. Tang and K. Wiesenfeld, Phys. Rev. Lett. {\bf 59}, 381 (1987)], and stochastic, such as the Manna model [S.S. Manna, J. Phys. A {\bf 24}, L363 (1991)], are studied on finite square lattices with open boundaries. The avalanche size distribution $P_L(n)$ is c

D. Porras, C. Tejedor

Polaritons in semiconductor microcavities can experience a Bose-Einstein condensation experimentally detectable in the spectrum of the emitted light. Scattering with noncondensed particles as well as self-interaction in the condensate provoke phase-diffusion limiting the coherence of the polariton condensate. We present a theoretical analysis of self-interac

S. Tajima, S. Uchida, D. van der Marel, D. N. Basov

Recently Lucarelli {\it et al.} have reported\cite{lucarelli} temperature-dependence of the in-plane optical reflectivity of La$_{2-x}$Sr$_x$CuO$_4$ over a wide doping range, focusing on the infrared peaks at 30 cm$^{-1}$ (for $x$=0.12), 250 cm$^{-1}$ and 510 cm$^{-1}$. They interpreted the first peak (30 cm$^{-1}$) as a signature of charge stripe ordering,

L. P. Kondaurova, S. K. Nemirovskii, M. V. Nedoboiko

We present the results of simulation of the chaotic dynamics of quantized vortices in the bulk of superfluid He II. Evolution of vortex lines is calculated on the base of the Biot-Savart law. The dissipative effects appeared from the interaction with the normal component, or/and from relaxation of the order parameter are taken into account. Chaotic dynamics

C. L. Yang, M. A. Zudov, T. A. Knuuttila, R. R. Du

Using Corbino samples we have observed oscillatory conductance in a high-mobility two-dimensional electron system subjected to crossed microwave and magnetic fields. On the strongest of the oscillation minima the conductance is found to be vanishingly small, possibly indicating an insulating state associated with these minima.

Dirk Helbing, Illes Farkas, Tamas Vicsek

Simulation software used to produce results in cond-mat/0009448 -- published as Helbing et.al, Simulating Dynamical Features of Escape Panic, Nature 407, 487-490 (2000) -- has been made available via the website of the publication at http://angel.elte.hu/panic

Ph. Jacquod, H. Schomerus, C. W. J. Beenakker

We introduce quantum maps with particle-hole conversion (Andreev reflection) and particle-hole symmetry, which exhibit the same excitation gap as quantum dots in the proximity to a superconductor. Computationally, the Andreev maps are much more efficient than billiard models of quantum dots. This makes it possible to test analytical predictions of random-mat

J. Lopez, O. F. de Lima

We have made a magnetic characterization of Nd0.5Sr0.5MnO3, Nd0.5Ca0.5MnO3, Sm0.5Ca0.5MnO3, Dy0.5Ca0.5MnO3 and Ho0.5Ca0.5MnO3 polycrystalline samples. Ferromagnetic, antiferromagnetic and charge ordering transitions in our samples agree with previous reports. We also report specific heat measurements with applied magnetic fields between 0 and 9 T and tempera

J. B. Hutchings

Imaging and spectra of the lensed QSO pair 0957+561 are presented and discussed. The data are principally those from the STIS NUV MAMA, and cover rest wavelengths from 850A to 1350A. The QSOs are both extended over about 1 arcsec, with morphology that matches with a small rotation, and includes one feature aligned with the VLBI radio jets. This is the first

C. Sneden, J. J. Cowan, J. E. Lawler, I. I. Ivans

High-resolution spectra obtained with three ground-based facilities and the Hubble Space Telescope (HST) have been combined to produce a new abundance analysis of CS 22892-052, an extremely metal-poor giant with large relative enhancements of neutron-capture elements. A revised model stellar atmosphere has been derived with the aid of a large number of Fe-pe

P. Bodenheimer, G. Laughlin, D. N. C. Lin

We have computed evolutionary models for extrasolar planets which range in mass from 0.1 to 3.0 Jovian Masses, and which range in equilibrium temperature from 113 K to 2000 K. We present four sequences of models, designed to show the structural effects of a solid core and of internal heating due to the conversion of kinetic to thermal energy at pressures of

Xu Kong, Stephane Charlot, Achim Weiss, Fuzhen Cheng

This is the third paper of a series dedicated to the study of the star formation rates, star formation histories, metallicities and dust contents of a sample of blue compact galaxies (BCGs). We constrain the stellar contents of 73 blue compact galaxies by analyzing their continuum spectra and the equivalent widths of strong stellar absorption features using

Knox S. Long, Cynthia S. Froning, Boris Gaensicke, Christian Knigge

The short-period cataclysmic variable WZ Sge underwent its first dwarf nova outburst in 23 years in 2001 July. Here we describe 905-1187 Ang. spectra obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) during the outburst and within the first few months after the outburst. The first spectrum, obtained about 7 days after the outburst began and 6.4

S. Chaty, P. A. Charles, J. Marti, I. F. Mirabel

We present photometric and spectroscopic optical and near-infrared (NIR) observations (Based on observations collected at the European Southern Observatory, Chile (ESO ID 63.H-0493 and 64.H-0382)) taken during the outburst of the microquasar V4641 Sgr = SAX J1819.3-2525 (in'tzand et al., 2000) in September 1999. We observed an increase in the J-Ks colour

Eric S. Perlman, Christopher Frye, Harald Ebeling, Laurence R. Jones

We are conducting a deep radio survey of a sample of 25 distant ($0.5<z<1$) clusters of galaxies. Here we present a progress report. So far 17 of 25 clusters have been observed, to varying depths. We have found 33 radio sources within 0.3 Abell radii of the cluster center, of which 28 are likely associated with cluster member galaxies. A comparison of the ra

B. Vollmer, T. Beckert

An analytical model for a turbulent clumpy gas disk is presented where turbulence is maintained by the energy input due to supernovae. Expressions for the disk parameters, global filling factors, molecular fractions, and star formation rates are given as functions of the Toomre parameter $Q$, the ratio between the cloud size and the turbulent driving length

X. Barcons, R. Carballo, F. J. Carrera, M. T. Ceballos

We present new XMM-Newton X-ray observations of the z=1.246 narrow-line radioquasar RX J1011.2+5545 serendipitously discovered by ROSAT. The flat X-ray spectrum previously measured by ROSAT and ASCA is shown to be the result of a steep Gamma~1.8 power law spectrum seen through a moderate intrinsic absorbing column NH~4E21 cm^-2. The position of the X-ray sou

Sadegh Khochfar, Andreas Burkert

We use semi-analytical modelling techniques to investigate the progenitor morphologies of present day ellipticals. We find that, independent of the environment, the fraction of mergers of bulge dominated galaxies (early-types) increases with time. The last major merger of bright present day ellipticals with $M_{B} \lesssim -21$ is preferentially between bulg

M. Kuerster, M. Endl, F. Rouesnel, S. Els

We report results from 2 1/2 yr of high precision radial velocity (RV) monitoring of Barnard&#39;s star. The high RV measurement precision of the VLT-UT2+UVES of 2.65 m/s made the following findings possible. (1) The first detection of the change in the RV of a star caused by its space motion (RV secular acceleration). (2) An anti-correlation of the measured

R. L. Smart, M. G. Lattanzi, B. Bucciarelli, G. Massone

We present parallax determinations for six white dwarf candidates in the Torino Observatory Parallax Program. The absolute parallaxes are found with precisions at the 2-3 milliarcsecond level. For WD 1126+185 we find a distance incompatible with being a white dwarf, implying an incorrect classification. For WD 2216+484 we find our distance is consistent with

T. Multamaki, E. Gaztanaga, M. Manera

We study the growth of large scale structure in two recently proposed non-standard cosmological models: the brane induced gravity model of Dvali, Gabadadze and Porrati (DGP) and the Cardassian models of Freese and Lewis. A general formalism for calculating the growth of fluctuations in models with a non-standard Friedman equation and a normal continuity equa

E. Meyer-Hofmeister, F. Meyer

We develop a new method to describe the accretion flow in the corona above a thin disk around a black hole in vertical and radial extent. The model is based on the same physics as the earlier one-zone model, but now modified including inflow and outflow of mass, energy and angular momentum from and towards neighboring zones. We determine the radially extende

Shiv K. Sethi

We study the effect of large scale tangled magnetic fields on the galaxy two-point correlation function in the redshift space. We show that (a) the magnetic field effects can be comparable the gravity-induced clustering for present magnetic field strength $B_0 \simeq 5 \times 10^{-8}$ G, (b) the absence of this signal from the present data gives an upper bou

A. -C. Donea, R. J. Protheroe

The existence of intrinsic obscuration of Fanaroff-Riley I objects is a controversial topic. M87, the nearest such object, is puzzling in that although it has very massive central black hole it has a relatively low luminosity, suggesting it is in a dormant state. Despite of its proximity to us (16 Mpc) it is not known with certainty whether or not M87 has a

James Wadsley, Joachim Stadel, Thomas Quinn

The key algorithms and features of the Gasoline code for parallel hydrodynamics with self-gravity are described. Gasoline is an extension of the efficient Pkdgrav parallel N-body code using smoothed particle hydrodynamics. Accuracy measurements, performance analysis and tests of the code are presented. Recent successful Gasoline applications are summarized.

Francis P. Wilkin, Steven W. Stahler

Observations show that high-velocity jets stem from deeply embedded young stars, which may still be experiencing infall from their parent cloud cores. Yet theory predicts that, early in this buildup, any outgoing wind is trapped by incoming material of low angular momentum. As collapse continues and brings in more rapidly rotating gas, the wind can eventuall

H. Mathis, J. Silk, L. M. Griffiths, M. Kunz

Using cosmological simulations, we make predictions for the distribution of clusters in a plausible non-gaussian model where primordial voids nucleated during inflation act together with scale-invariant adiabatic gaussian fluctuations as seeds for the formation of large-scale structure. This model agrees with most recent observations of the anisotropies of t

E. Bartos, E. A. Kuraev, S. Dubnicka

Starting from very high energy inelastic electron-nucleon scattering with a production of a hadronic state $X$ to be moved closely to the direction of the initial nucleon, then utilizing analytic properties of parts of forward virtual Compton scattering amplitudes on proton and neutron, one obtains the relation between nucleon form factors and a difference o

Anatoly Dymarsky, Dmitry Melnikov

In N=2 SYM theory with matter non-conservation of the S-charge of a BPS state under monodromies leads to so-called BPS state &#34;decay&#34;. A mechanism for such a behavior on the semiclassical level could be established through consideration of soliton-fermion bound state. Solutions to classical equations of motion allow to observe the BPS state &#34;decay

Douglas Lind

We formulate Lehmer&#39;s Problem about the Mahler measure of polynomials for general compact abelian groups, introducing a Lehmer constant for each such group. We show that all nontrivial connected compact groups have the same Lehmer constant, and conjecture the value of the Lehmer constant for finite cyclic groups. We also show that if a group has infinite

D. Stepanenko, N. E. Bonesteel, D. P. DiVincenzo, G. Burkard

We study the effect of spin-orbit coupling on quantum gates produced by pulsing the exchange interaction between two single electron quantum dots. Spin-orbit coupling enters as a small spin precession when electrons tunnel between dots. For adiabatic pulses the resulting gate is described by a unitary operator acting on the four-dimensional Hilbert space of

Christian Buth, Robin Santra, Lorenz S. Cederbaum

A hole in a 4d orbital of atomic xenon relaxes through Auger decay after a lifetime of 3 fs. Adding electronegative fluorine ligands to form xenon fluoride molecules, results in withdrawal of valence-electron density from Xe. Thus, within the one-center picture of Auger decay, a lowered Xe 4d Auger width would be expected, in contradiction, however, with exp

H. Grigorian, D. Blaschke, D. N. Aguilera

The equation of state for quark matter is derived for a nonlocal, chiral quark model within the mean field approximation. Special emphasis is on the occurrence of a diquark condensate which signals a phase transition to color superconductivity and its effects on the equation of state. We present a fit formula for the Bag pressure, which is density dependent

J. Kluson

In this note we will study solution of open bosonic string field theory based on action of operators from chiral algebra of boundary conformal field theory on identity element of string field theory star algebra. We will demonstrate that the string field theory action for fluctuation fields around this classical solution can be mapped to the string field the

Christophe A. Perrot, Isabelle A. Grenier

The dynamical evolution of the Gould Belt has been modelled in 3D and confronted to the spatial and velocity distributions of all HI and H2 clouds found within a few hundred parsecs from the Sun and to the Hipparcos distances of the nearby OB associations. The model describes the expansion of a shock wave that sweeps momentum from the ambient medium and it i

J. S. Bloom, D. Fox, P. G. van Dokkum, S. R. Kulkarni

Given the paucity of empirical constraints, the nature of the newly-recognized phenomena called X-Ray Flashes (XRFs) has been an open question. However, with the recent detections of radio and X-ray afterglow it is finally possible to study the large- and small-scale environments of XRFs. We present Chandra, Hubble Space Telescope (HST), and Keck observation

Alastair Brodlie

p-Mechanics is a consistent physical theory which describes both quantum and classical mechanics simultaneously. We continue the development of p-mechanics by introducing the concept of states. The set of coherent states we introduce allow us to evaluate classical observables at any point of phase space simultaneously to evaluating quantum probability amplit

H. M. Wiseman

Is the destruction of interference by a which-way measurement due to a random momentum transfer $\wp\agt\hbar/s$, with $s$ the slit separation? The weak-valued probability distribution $P_{\rm wv}(\wp)$, which is {\em directly observable}, provides a subtle answer. $P_{\rm wv}(\wp)$ cannot have support on the interval $[-\hbar/s,\hbar/s]$. Nevertheless, its

A. Marinov, S. Gelberg, D. Kolb, R. Brandt

Recently long-lived high spin super- and hyperdeformed isomeric states with unusual radioactive decay properties have been discovered. Based on these newly observed modes of radioactive decay, consistent interpretations are suggested for previously unexplained phenomena seen in nature. These are the Po halos, the low-energy enhanced 4.5 MeV alpha-particle gr

M. Turek, K. Richter

We semiclassically derive the leading off-diagonal correction to the spectral form factor of quantum systems with a chaotic classical counterpart. To this end we present a phase space generalization of a recent approach for uniformly hyperbolic systems (M. Sieber and K. Richter, Phys. Scr. T90, 128 (2001); M. Sieber, J. Phys. A: Math. Gen. 35, L613 (2002)).

Abhishek Dhar, D. Madhusudana Rao, N. Udaya Shankar, S. Sridhar

We consider a modification of isospectral cavities whereby the classical dynamics changes from pseudointegrable to chaotic. We construct an example where we can prove that isospectrality is retained. We then demonstrate this explicitly in microwave resonators.

Paolo Amore, Alfredo Aranda

We apply the Linear Delta Expansion (LDE) to the Lindstedt-Poincare (``distorted time&#39;&#39;) method to find improved approximate solutions to nonlinear problems. We find that our method works very well for a wide range of parameters in the case of the anharmonic oscillator (Duffing equation) and of the non-linear pendulum. The approximate solutions found

U. Frauenfelder, F. Schlenk

We study the dynamics of Hamiltonian diffeomorphisms on convex symplectic manifolds. To this end we first establish the Piunikhin-Salamon-Schwarz isomorphism between the Floer homology and the Morse homology of such a manifold, and then use this isomorphism to construct a biinvariant metric on the group of compactly supported Hamiltonian diffeomorphisms anal

Gyeong Yun Jun, Pyung Seong Kwon

We examine in the framework of 5d Kaluza-Klein theory the gauge equivalence of $x^5$-dependent cosmological solutions each of which describes in the 4d sector an arbitrarily evolving isotropic, homogeneous universe with some pure gauge. We find that (1)within a certain time scale $τ_c$ (which is characterized by the compactification radius $R_c$) any arbitra

Hai-Yang Cheng

Charmed meson decays into a pseudoscalar meson P and a tensor meson T are studied. The charm to tensor meson transition form factors are evaluated in the Isgur-Scora-Grinstein-Wise (ISGW) quark model. It is shown that the Cabibbo-allowed decay $D_s^+\to f_2(1270)π^+$ is dominated by the W-annihilation contribution and has the largest branching ratio in $D\to

Masayasu Harada, Masaharu Tanabashi, Koichi Yamawaki

We calculate pi+ pi0 mass difference $Δm_π^2 \equiv m_{π^+}^2 -m_{π^0}^2$ in the Hidden Local Symmetry (HLS) model, based on the Wilsonian matching and Wilsonian renormalization-group equations. Even without a1 meson the result agrees well with the experiment in sharp contrast to the conventional approach where the a1 meson plays a crucial role. For large Nf

Marije Ljolje

The theory of gravitation field within the special theory of relativity is analyzed.

Erik D. Demaine, Martin L. Demaine, David Eppstein, Greg N. Frederickson

A hinged dissection of a set of polygons S is a collection of polygonal pieces hinged together at vertices that can be folded into any member of S. We present a hinged dissection of all edge-to-edge gluings of n congruent copies of a polygon P that join corresponding edges of P. This construction uses kn pieces, where k is the number of vertices of P. When P

Lauro Lins, Sostenes Lins, Silvio Melo

In this paper we propose a simple and efficient data structure yielding a perfect hashing of quite general arrays. The data structure is named phorma, which is an acronym for perfectly hashable order restricted multidimensional array. Keywords: Perfect hash function, Digraph, Implicit enumeration, Nijenhuis-Wilf combinatorial family.

L. Velazquez, F. Guzman

According to self-similarity hypothesis, the thermodynamic limit could be defined from the scaling laws for the system self-similarity by using the microcanonical ensemble. This analysis for selfgravitating systems yields the following thermodynamic limit: send N to infinity, keeping constant E/N^{(7/3)} and LN^{(1/3)}, in which is ensured the extensivity of

Trinh Van Khoa

In this papers it is showed, that for the noncommutative deformation simultaneously exist also loading deformation $H $, and unloading deformation $H^v $. The real deformation is a combination of these types deformations. The criterion of destruction $J $ reflects topological character of environment, i.e. defines properties of symmetry of environment at des

J. G. E. Harris, R. Knobel, K. D. Maranowski, A. C. Gossard

We find that the damping of micromechanical cantilevers is sensitive to the relaxation dynamics of paramagnetic ions contained within the levers. We measure cantilevers containing paramagnetic Mn ions as a function of temperature, magnetic field, and the vibrational mode of the lever and find that the levers damping is strongly enhanced by the interplay betw

G. L. Eyink, S. Chen, Q. Chen

We show that Kolmogorov multipliers in turbulence cannot be statistically independent of others at adjacent scales (or even a finite range apart) by numerical simulation of a shell model and by theory. As the simplest generalization of independent distributions, we suppose that the steady-state statistics of multipliers in the shell model are given by a tran

E. Waxman

A pedagogical derivation is presented of the ``fireball&#39;&#39; model of gamma-ray bursts, according to which the observable effects are due to the dissipation of the kinetic energy of a relativistically expanding wind, a ``fireball.&#39;&#39; The main open questions are emphasized, and key afterglow observations, that provide support for this model, are b

Michel Vittot

We consider a perturbation of an ``integrable&#39;&#39; Hamiltonian and give an expression for the canonical or unitary transformation which ``simplifies&#39;&#39; this perturbed system. The problem is to invert a functional defined on the Lie- algebra of observables. We give a bound for the perturbation in order to solve this inversion. And apply this resul

Adil Belhaj

Using a reformulation of the method of (p,q) webs, we study the four-dimensional N=1 quiver theories from M-theory on seven-dimensional manifolds with G_2 holonomy. We first construct such manifolds as U(1) quotients of eight-dimensional toric hyper-Kähler manifolds, using N=4 supersymmetric sigma models. We show that these geometries, in general, are given

T. Blazek, S. F. King, J. K. Parry

We perform a complete global phenomenological analysis of a realistic string-inspired model based on the supersymmetric Pati-Salam $SU(4)\times SU(2)_L \times SU(2)_R$ gauge group supplemented by a U(1) family symmetry, and present predictions for all observables including muon $g-2$, $τ\to μγ$, and the CHOOZ angle. Our analysis demonstrates the compatibilit

M. R. Evans, R. Juhasz, L. Santen

We investigate shock formation in an asymmetric exclusion process with creation and annihilation of particles in the bulk. We show how the continuum mean-field equations can be studied analytically and hence derive the phase diagrams of the model. In the large system-size limit direct simulations of the model show that the stationary state is correctly descr

Dominique Spehner

The spectral fluctuations of a quantum Hamiltonian system with time-reversal symmetry are studied in the semiclassical limit by using periodic-orbit theory. It is found that, if long periodic orbits are hyperbolic and uniformly distributed in phase space, the spectral form factor agrees with the GOE prediction of random-matrix theory up to second order inclu

U. Al Khawaja, N. P. Proukakis, J. O. Andersen, M. W. J. Romans

We investigate the long-range phase coherence of homogeneous and trapped Bose gases as a function of the geometry of the trap, the temperature, and the mean-field interactions in the weakly interacting limit. We explicitly take into account the (quasi)condensate depletion due to quantum and thermal fluctuations, i.e., we include the effects of both phase and

Marek Gierlinski, Andrzej A. Zdziarski

We have found a large number of very strong flares in the available XTE PCA data of Cyg X-1 (also seen in available HEXTE and BATSE data) with 13 flares satisfying our chosen threshold criterion, occuring both in the hard and the soft states. We analyze here in detail two of them. The strongest one took place in the soft state, with the 3-30 keV energy flux

O. Long, M Baak, R. N. Cahn, D. Kirkby

Interference between CKM-favored b --> c ubar d and doubly-CKM-suppressed bbar --> ubar c dbar amplitudes in final states used for B flavor tagging gives deviations from the standard time evolution assumed in CP-violation measurements at B factories producing coherent B0 B0bar pairs. We evaluate these deviations for the standard time-dependent CP-violation m

V. A. Chechin, V. A. Tsarev, M. Rabinowitz, Y. E. Kim

We briefly summarize the reported anomalous effects in deuterated metals at ambient temperature, commonly known as &#34;Cold Fusion&#34; (CF), with an emphasis on important experiments as well as the theoretical basis for the opposition to interpreting them as cold fusion. Then we critically examine more than 25 theoretical models for CF, including unusual n

Roman V. Buniy, Thomas W. Kephart

We show how the existence of non-trivial finite-energy time-dependent classical lumps is restricted by a generalized virial theorem. For simple model Lagrangians, bounds on energies follow.

Yuri N. Obukhov, Friedrich W. Hehl

We discuss the electromagnetic energy-momentum distribution and the mechanical forces of the electromagnetic field in material media. There is a long-standing controversy on these notions. The Minkowski and the Abraham energy-momentum tensors are the most well-known ones. We propose a solution of this problem which appears to be natural and self-consistent f

Oliver Beckstein, Mark S. P. Sansom

Water plays a key role in biological membrane transport. In ion channels and water-conducting pores (aquaporins), one dimensional confinement in conjunction with strong surface effects changes the physical behavior of water. In molecular dynamics simulations of water in short (0.8 nm) hydrophobic pores the water density in the pore fluctuates on a nanosecond

J. L. Friar, U. van Kolck, G. L. Payne, S. A. Coon

Charge-symmetry breaking in the nucleon-nucleon force is investigated within an effective field theory, using a classification of isospin-violating interactions based on power-counting arguments. The relevant charge-symmetry-breaking interactions corresponding to the first two orders in the power counting are discussed, including their effects on the 3He-3H

Denis I. Borisov

Model two-dimensional singular perturbed eigenvalue problem for Laplacian with frequently alternating type of boundary condition is considered. Complete two-parametrical asymptotics for the eigenelements are constructed.

M. M. Shakir&#39;yanov, V. G. Volkov

The classical solvability of the initial-boundary problem for the Davey-Stewartson-II type system of equations is proved.

R. J. Miatello, J. P. Rossetti

We study isospectrality on p-forms of compact flat manifolds by using the equivariant spectrum of the Hodge-Laplacian on the torus. We give an explicit formula for the multiplicity of eigenvalues and a criterion for isospectrality. We construct a variety of new isospectral pairs, for instance, pairs of flat manifolds of dimension n=2p, p>1, not homeomorphic

Yu-Jie Zhong, Wung-Hong Huang

The matrix model with mass term has a nontrivially classical solution which is known to represent a noncommutative fuzzy sphere. The fuzzy sphere has a lower energy then that of the trivial solution. In this letter we investigate the quantum correction of the energy of the fuzzy sphere by using the Gaussian variational technique, in contrast to the other stu

BABAR Collaboration, B. Aubert

We present a search for the decay $B^{+} \to τ^{+} ν_τ$ in $88.9 \times 10^{6}$ $Υ(4S)$ decays recorded with the BABAR detector at the SLAC $B$-Factory. A sample of semi-exclusive, semi-leptonic B decays ($B^{-} \to D^{0} \ell^{-} \bar{ν_{\ell}}X$), where $X$ is either a photon, $π^{0}$, or nothing, is used to identify the daughter particles that are associa

The DELPHI Collaboration, J. Abdallah

Searches for resonant sneutrino production in e+e- collisions under the assumption that R-parity is not conserved and that the dominant R-parity violating coupling is lambda_{121} or lambda_{131} used data recorded by DELPHI in 1997 to 2000 at centre-of-mass energies of 183 to 208 GeV. No deviation from the Standard Model was observed. Upper limits are given

The DELPHI Collaboration, J. Abdallah

Neutral B meson oscillations in the B0_s - anti-B0_s and B0_d - anti-B0_d systems were studied using a sample of about 4.0 million hadronic Z decays recorded by the DELPHI detector between 1992 and 2000. Events with a high transverse momentum lepton were removed and a sample of 770 k events with an inclusively reconstructed vertex was selected. The mass diff

The DELPHI Collaboration, J. Abdallah

The production of wrong sign charmed mesons b -> \bar D_{(s)} X, D_{(s)}=(D0,D+,D_s), is studied using the data collected by the DELPHI experiment in the years 1994 and 1995. Charmed mesons in Z -> b bbar events are exclusively reconstructed by searching for the decays D0 -> K- pi+, D+ -> K- pi+ pi+ and D_s^+ -> phi pi+ -> K+ K- pi+. The wrong sign contribut