August 1999 arXiv papers — page 7

Curtis Struck

Theories of how galaxies, the fundamental constituents of large-scale structure, form and evolve have undergone a dramatic paradigm shift in the last few decades. Earlier views were of rapid, early collapse and formation of basic structures, followed by slow evolution of the stellar populations and steady buildup of the chemical elements. Current theories em

Ian A. Bonnell

Observations have revealed that most stars are born in clusters. These systems, containing from tens to thousands of stars and typically significant mass in gas in the youngest systems, evolve due to a combination of stellar and star-gas interactions. Simulations of pure stellar systems are used to investigate possible initial configurations including ellipt

M. C. Wyatt, S. F. Dermott, C. M. Telesco, R. S. Fisher

Recent images of the disks of dust around the young stars HR 4796A and Fomalhaut show, in each case, a double-lobed feature that may be asymmetric (one lobe may be brighter than the other). A symmetric double-lobed structure is that expected from a disk of dust with a central hole that is observed nearly edge-on (i.e., close to the plane of the disk). This p

A. Lecavelier des Etangs, L. M. Hobbs, A. Vidal-Madjar, H. Beust

We present the results of exploratory HST observations to detect the emission lines of ions in the Beta Pic disk with the spectrograph slit placed off the star. Possible emission lines from FeII have been detected at $\sim 10^{-14}$erg cm-2 s-1 at 0.5 arcsec from Beta Pic, which would suggest a total FeII density of > 2.$10^{-2}$ cm-3 at 10 AU. This detectio

Ralph Neuhaeuser, Fernando Comeron

We obtained medium-resolution spectra of the bona-fide brown dwarf Cha H$α$ 1, the five brown dwarf candidates Cha H$α$ 2 to 6, two additional late M-type brown dwarf candidates, all originally selected by H$α$ emission, and four previously known T Tauri stars, all located in Chamaeleon I. The spectral types of our targets range down to M8. We show their spe

Sabine Philipp, Richard J. Tuffs, Peter G. Mezger, Robert Zylka

Infrared observations of IRAS 17393-3004, including a full scan ISOSWS are presented. The ISOSWS spectrum shows two prominent dust emission peaks at lambda 10.4mu and 17.5mu confirming that the source is a luminous star surrounded by a dust shell. The spectrum of the star, deduced from modeling of the radiative transfer through a spherical shell using the DU

Antonaldo Diaferio

For the first time, the combination of semi-analytic modelling of galaxy formation and N-body simulations of cosmic structure formation enables us to model, at the same time, both the photometric and the clustering properties of galaxies. Two Cold Dark Matter Universes provide a reasonable fit to the observed properties of galaxies, groups and clusters, incl

R. X. Xu, Z. G. Dai, B. H. Hong, G. J. Qiao

It is suggested that the inner energetic engine of Gamma ray burst (GRB) may be the result of the transition of normal hadron to quark-gluon plasma (QGP) in rapidly-rotating and spin-down newborn neutron star. When such a nascent neutron star slows down through dipole electromagnetic and quadruple gravitational radiation, the increasing center density may re

Christian R. Kaiser

Our knowledge of the environments of radio-loud AGN is still sketchy. However, to understand the jet phenomenon it is important to know about the properties of the surroundings in which jets are formed and evolve. Here I present an analytical model of the radio surface brightness distribution of the large scale structure of FRII-type radio sources. The `virt

Rene D. Oudmaijer, Janet E. Drew

We present time-resolved spectroscopy of the Be star HD 76534, which was observed to have an Halpha outburst in 1995, when the line went from photospheric absorption to emission at a level of more than two times the continuum within 2.5 hours. To investigate the short-term behaviour of the spectrum of HD 76534 we have obtained 30 spectra within two hours rea

Takashi Murayama, Hideaki Mouri, Yoshiaki Taniguchi

We propose a new diagnostic of the ``dusty torus&#39;&#39; model for Seyfert nuclei. Dust grains in the torus are heated by the nuclear continuum, and reradiate mostly in the mid-infrared wavelengths. From the torus geometry, it is predicted that the emission at lambda < 10 micron has strong dependence on the viewing angle. Since the dependence is predicted

Kelly Holley-Bockelmann, Douglas O. Richstone

In order for the core Fundamental Plane (cFP) to endure, small ellipticals must not survive mergers with giant ellipticals, despite the fact the small secondary galaxy can be as much as a million times more dense than the primary. However, our previous set of experiments has shown that, for purely stellar galaxies, the secondary does in fact survive mergers

I. -O. Stamatescu, T. T. Wu

We present a solvable model for describing quantitatively situations where the individual behaviour of agents in a group &#34;percolates&#34; to collective behaviour of the group as a whole as a result of mutual influence between the agents.

U. K. Yang, A. Bodek

We report on the extraction of the higher twist contributions to F_2 and R = sigma_L/sigma_T from the global NLO and NNLO QCD fits to lepton nucleon scattering data over a wide range of Q^2. The NLO fits require both target mass and higher twist contributions at low Q^2. However, in the NNLO analysis, the data are described by the NNLO QCD predictions (with

Andrzej Czarnecki, G. Peter Lepage, William J. Marciano

Modifications of the mu+ lifetime in matter due to muonium (M = mu+ e-) formation and other medium effects are examined. Muonium and free mu+ decay spectra are found to differ at O(alpha m_e/m_mu) from Doppler broadening and O(alpha^2 m_e/m_mu) from the Coulomb bound state potential. However, both types of corrections are shown to cancel in the total decay r

M. E. Carrington, Hou Defu, A. Hachkowski, D. Pickering

We construct a program to calculate Feynman amplitudes at finite temperature in the real time Keldysh formalism using the symbolic manipulation program {\it Mathematica}. As an example, the usefulness of this program is demonstrated by proving the finite temperature Ward identity for QED in a second order effective theory.

J. Feinberg, A. Mann, M. Revzen

We analyze the high temperature (or classical) limit of the Casimir effect. A useful quantity which arises naturally in our discussion is the ``relative Casimir energy&#34;, which we define for a configuration of disjoint conducting boundaries of arbitrary shapes, as the difference of Casimir energies between the given configuration and a configuration with

M. Bousquet-Melou, A. J. Guttmann, W. P. Orrick, A. Rechnitzer

We derive self-reciprocity properties for a number of polyomino generating functions, including several families of column-convex polygons, three-choice polygons and staircase polygons with a staircase hole. In so doing, we establish a connection between the reciprocity results known to combinatorialists and the inversion relations used by physicists to solv

Simon Villain-Guillot, Giancarlo Jug, Klaus Ziegler

The density of states of Dirac fermions with a random mass on a two-dimensional lattice is considered. We give the explicit asymptotic form of the single-electron density of states as a function of both energy and (average) Dirac mass, in the regime where all states are localized. We make use of a weak-disorder expansion in the parameter g/m^2, where g is th

Stefano Ettori

In this note, I suggest that the beta-model used to fit the X-ray surface brightness profiles of extended sources, like groups and clusters of galaxies, has to be corrected when the counts are collected in a wide energy band comparable to the mean temperature of the source and a significant gradient in the gas temperature is observed. I present a revised ver

C. S. Kim, J. D. Kim

We show that not only the hierarchical quark CKM mixing matrix but also the &#34;bimaximal&#34; lepton flavor mixing matrix can be derived from the same mass matrix ansatz based on the broken permutation symmetry, by assuming the hierarchy of neutrino masses to be $m_1\simeq m_2 <<m_3$. We also reproduce the recently measured angle of unitary triangle, $\sin

D. Bardin, M. Bilenky, P. Christova, M. Jack

We describe ZFITTER, a Fortran program based on a semi-analytical approach to fermion pair production in e+e- annihilation at a wide range of centre-of-mass energies, including the PETRA, TRISTAN, LEP1/SLC, and LEP2 energies. A flexible treatment of complete O(alpha) QED corrections and of some higher order contributions is made possible with three calculati

Ikuo Ichinose

We study two-dimensional Dirac fermions in a random non-Abelian vector potential by using lattice regularization. We consider U(N) random vector potential for large $N$. The ensemble average with respect to random vector potential is taken by using lattice supersymmetry which we introduced before in order to investigate phase structure of supersymmetric gaug

Michal Chodorowski

I derive a nonlinear local relation between the redshift-space density field and the real-space velocity field. The relation accounts for radial character of redshift distortions, and it is not restricted to the limit of the distant observer. Direct comparisons between the observed redshift-space density fields and the real-space velocity fields possess all

S. Fortunato, H. Satz

We show that deconfinement in SU(2) gauge theory can be described by the percolation of site-bond clusters of like-sign Polyakov loops. In particular, we find that in 2+1 dimensions the percolation variables coincide with those of the 2-dimensional Ising model.

Peter D. D. Schwindt, Paul G. Kwiat, Berthold-Georg Englert

The notion of wave-particle duality may be quantified by the inequality V^2+K^2 <=1, relating interference fringe visibility V and path knowledge K. With a single-photon interferometer in which polarization is used to label the paths, we have investigated the relation for various situations, including pure, mixed, and partially-mixed input states. A quantum

Koo-Chul Lee

We report several simulation programs which can be used to teach the statistical foundation of thermal physics in the introductory college physics courses. These programs are simple applications of a technique of generating random configurations of many dice with fixed total value. By simulating dice throwing only we can demonstrate all the important princip

P. Maris

We calculate the critical exponents of the chiral phase transition at nonzero temperature using the thermal and chiral susceptibilities. We show that within a class of confining Dyson-Schwinger equation (DSE) models the transition is mean field, and that an accurate determination of the critical exponents requires extremely small values of the current-quark

Yu. E. Titarenko, O. V. Shvedov, V. F. Batyaev, E. I. Karpikhin

The results of measurements and computer simulations of radioactivities and dose rates as functions of decay time are presented for Pb-nat and Bi-209 irradiated by 1.5-GeV protons, Co-59, Cu-63, and Cu-65 irradiated by 0.13- and 1.2-GeV protons, and Th-232 and U-nat irradiated by 0.1- and 0.8-GeV protons. The activities and dose rates are measured by direct

C. Quesne

The anomalous bilinear commutation relations satisfied by the components of the Green&#39;s ansatz for paraparticles are shown to derive from the comultiplication of the paraboson or parafermion algebra. The same provides a generalization of the ansatz, wherein paraparticles of order $p=\sum_{α=1}^r p_α$ are constructed from r paraparticles of order $p_α$, $

C. Quesne, N. Vansteenkiste

C$_λ$-extended oscillator algebras, where C$_λ$ is the cyclic group of order $λ$, are introduced and realized as generalized deformed oscillator algebras. For $λ=2$, they reduce to the well-known Calogero-Vasiliev algebra. For higher $λ$ values, they are shown to provide in their bosonic Fock space representation some interesting applications to supersymmetr

Emmanuel Giroux

The main purpose of this article is to classify contact structures on some 3-manifolds, namely lens spaces, most torus bundles over a circle, the solid torus, and the thickened torus T^2 x [0,1]. This classification completes earlier work (by Etnyre [math.DG/9812065], Eliashberg, Kanda, Makar-Limanov, and the author) and results from the combination of two t

Phung Ho Hai

In this work we study some properties of comldules over (non-cosemisimple) Hopf algebras possessing integrals, which are also called co-Frobenius Hopf algebras. We apply the result obtained to the classification of representations of quantum groups of type $A_{0|0}$.

C. W. Stark

Blowing up a point p in a manifold M builds a new manifold M&#39; in which p is replaced by the projectivization of the tangent space of M at p. This well-known operation also applies to fixed points of diffeomorphisms, yielding continuous homomorphisms between automorphism groups of M and M&#39;. The construction for maps involves a loss of regularity and i

David S. Burggraf

Until now, only examples of solvable Galois actions on classes of dessins d&#39;enfants have been explicitly constructed. In this paper, an action of the nonsolvable alternating group $A_5$, represented as a Galois group on a class of dessins is presented.

Alexander Brudnyi

We estimate the expected number of limit cycles situated in a neighbourhood of the origin of a planar polynomial vector field. Our main tool is a distributional inequality for the number of zeros of some families of univariate holomorphic functions depending analytically on a parameter. We obtain this inequality by methods of Pluripotential Theory. This ineq

Alexander Brudnyi

We study traces of a class of subharmonic functions to Ahlfors regular subsets of $\Co^{n}$. In particular, we establish for the traces a generalized BMO-property and the reverse Hölder inequality.

Alex Chigogidze, V. V. Fedorchuk

We show that the n-homotopy category of connected (n+1)-dimensional Menger manifolds is isomorphic to the homotopy category of connected Hilbert cube manifolds whose k-dimensional homotopy groups are trivial for each k > n.

Nik Weaver

We examine Hilbert bimodules which possess a (generally unbounded) involution. Topics considered include a linking algebra representation, duality, locality, and the role of these bimodules in noncommutative differential geometry.

Tyler J. Jarvis

This article treats the Picard group of the moduli (stack) of r-spin curves and its compactification. Generalized spin curves, or r-spin curves are a natural generalization of 2-spin curves (algebraic curves with a theta-characteristic), and have been of interest lately because they are the subject of a remarkable conjecture of E. Witten, and because of the

Danny Birmingham, Siddhartha Sen

We study the formation of BTZ black holes by the collision of point particles. It is shown that the Gott time machine, originally constructed for the case of vanishing cosmological constant, provides a precise mechanism for black hole formation. As a result, one obtains an exact analytic understanding of the Choptuik scaling.

Paolo Di Vecchia

In the first part of these lectures we will review the main aspects of large N QCD and the explicit results obtained from it. Then, after a review of the properties of N=4 super Yang-Mills, type IIB string theory and of AdS space, we briefly discuss the Maldacena conjecture. Finally in the last part of these lectures we will discuss the finite temperature ca

Tarek Ibrahim, Pran Nath

Effects of CP violation on the supersymmetric electro-weak correction to the anomalous magnetic moment of the muon are investigated with the most general allowed set of CP violating phases in MSSM. The analysis includes contributions from the chargino and the neutralino exchanges to the muon anomaly. The supersymmetric contributions depend only on specific c

S. I. Kruglov

The exact solutions of the equation for a composite scalar particle which possesses electric and magnetic polarizabilities are found in an external uniform static magnetic field parallel to the direction of propagation of the quantized electromagnetic wave. As a particular case, the relativistic coherent states of a particle in the field of photons were cons

Rajan Gupta

An overview of lattice results for the strange quark mass, $B_K$, $B_6$, $B_7$, and $B_8$ is presented. I give my assessment of the reliability of various estimates and prospects for future improvements.

Vincenzo Barone, Alessandro Drago

We briefly review the present theoretical and experimental knowledge on Delta_g and J_g.

Yue-Liang Wu

I mainly describe neutrino masses and oscillations in the gauge model with $SO(3)_{F}$ lepton flavor symmetry and with two Higgs triplets. It is shown how the maximal mixing between $ν_μ$ and $ν_τ$ neutrinos comes out naturally after spontaneous breaking of the symmetry. The nearly two-flavor mixing scenario is resulted naturally from an approximate permutat

Nils A. Tornqvist

A new mechanism for breaking an internal symmetry spontaneously is discussed, which is intermediate between the Nambu-Goldstone and Wigner modes of symmetry breaking. Here the quark-antiquark sea takes the role of the vacuum of the Nambu-Goldstone case. Flavour symmetry becomes a discrete permutation symmetry of the valence quarks with respect to the sea qua

Apostolos Pilaftsis

Recently, it has been found that the tree-level CP invariance of the Higgs potential in the MSSM can be sizeably broken by loop effects due to soft-CP-violating trilinear interactions involving third generation scalar quarks. These soft-CP-violating couplings may be constrained by considering new two-loop contributions to the electron and neutron EDMs. The p

Elena Gubankova, Chueng-Ryong Ji, Stephen R. Cotanch

The systematic approach to study bound states in gluodynamics is presented. The method utilizes flow equations together with low-energy phenomenology, that provides the perturbative renormalization scaling in conjuction with the change of the basis to constituent gluon states. The renormalized effective Hamiltonian of gluodynamics up to the second order is o

J. J. van der Bij, Boris Kastening

We investigate the effects of WW rescattering through strong anomalous four-vector boson couplings. In the I=1, J=1 channel, we find a resonance with a mass of approximately 200 GeV and a width of less than 12 GeV. In an application to pion physics we find a small correction to the KSRF relation.

Thomas DeGrand

I implement a set of tricks for constructing lattice fermion actions which approximately realize the Ginsparg-Wilson relation, with very promising results from simulations.

Robert G. Edwards, Urs M. Heller, Joe Kiskis, Rajamani Narayanan

We investigate the realization of chiral symmetry in the vicinity of the deconfinement transition in quenched QCD using overlap fermions. Via the index theorem obeyed by the overlap fermions, we gain insight into the behavior of topology at finite temperature. We find small eigenvalues, clearly separated from the bulk of the eigenvalues, and study the proper

S. Dalley, B. van de Sande

Ideas and recent results for light-front Hamiltonian quantisation of lattice gauge theories.

Werner Kerler

Normality and $\ga$-hermiticity are what gives rise to chiral properties and rules. The Ginsparg-Wilson (GW) relation is only one of the possible spectral constraints. The sum rule for chiral differences of real modes has important consequences. The alternative transformation of Lüscher gives the same Ward identity as the usual chiral one (if zero modes are

L. C. Garcia de Andrade

An example of a teleparallel texture is given by an appropriate choice of torsion components in the tetrad frame.In the light cone limit the metric is not globally Euclidean and the spherical angles depend on torsion similarly to what happens in cosmic string space-times.In this limit torsion produces a force which decays with $r^{-3}$.

A. E. Jacobs, D. Mukamel, D. W. Allender

We study the Landau model of the class of incommensurate systems with a scalar order parameter where the modulated phase is driven by a gradient-squared term with negative coefficient. For example, theoretical studies of cholesteric liquid crystals in a field (electric or magnetic) suggest that such an modulated phase should exist at high chirality. The bulk

L. Alff, S. Meyer, S. Kleefisch, U. Schoop

We have measured the temperature dependence of the in-plane London penetration depth lambda(T) and the maximum Josephson current Ic(T) using bicrystal grain boundary Josephson junctions of the electron-doped cuprate superconductor Nd(1.85)Ce(0.15)CuO(4-y). Both quantities reveal an anomalous temperature dependence below about 4 K. In contrast to the usual mo

M. Roepke, E. Holland-Moritz, B. Buechner, H. Berg

We have performed inelastic magnetic neutron scattering experiments on La(2-x-y)Sr(x)Nd(y)CuO(4) in order to study the Nd 4f-spin dynamics at low energies. In all samples we find at high temperatures a quasielastic line (Lorentzian) with a line width which decreases on lowering the temperature. The temperature dependence of the quasielastic line width Gamma/

N. Hayashi

The nondissipative transverse force acting on one moving vortex under the influence of another vortex is discussed in fermionic superfluid systems, where the relative velocity between the vortices is finite. On the basis of detailed numerical solutions of the Bogoliubov-de Gennes equation, the Berry phase for an adiabatic motion of the vortex line is examine

S. S. Manna

Self-Organized Criticality is the emergence of long-ranged spatio-temporal correlations in non-equilibrium steady states of slowly driven systems without fine tuning of any control parameter. Sandpiles were proposed as prototypical examples of self-organized criticality. However, only some of the laboratory experiments looking for the evidence of criticality

C. C. Almasan, E. Cimpoiasu, G. A. Levin, H. Zheng

We present a novel approach to the analysis of the normal state in-plane $σ_{ab}$ and out-of-plane $σ_{c}$ conductivities of anisotropic layered crystals such as oxygen deficient $YBa_{2}Cu_{3}O_{x}$. It can be shown that the resistive anisotropy is determined by the ratio of the phase coherence lengths in the respective directions; i.e., $σ_{ab}/σ_c=\ell_{a

Daniel D. Kelson, Garth D. Illingworth, Pieter G. van Dokkum, Marijn Franx

We define a large sample of galaxies for use in a study of the fundamental plane in the intermediate redshift cluster CL1358+62 at $z=0.33$. We have analyzed high resolution spectra for 55 members of the cluster. The data were acquired with the Low Resolution Imaging Spectrograph on the Keck I 10m telescope. A new algorithm for measuring velocity dispersions

Peter Englmaier, Isaac Shlosman

We analyze formation of grand-design two-arm spiral structure in the nuclear regions of disk galaxies. Such morphology has been recently detected in a number of objects using high-resolution near-infrared observations. Motivated by the observed (1) continuity between the nuclear and kpc-scale spiral structures, and by (2) low arm-interarm contrast, we apply

C. G. Mundell, A. S. Wilson, J. S. Ulvestad, A. L. Roy

We present high angular resolution (~2 mas) radio continuum observations of five Seyfert galaxies with flat-spectrum radio nuclei, using the VLBA at 8.4 GHz. The goal of the project is to test whether these flat-spectrum cores represent thermal emission from the accretion disk, as inferred previously by Gallimore et al. for NGC 1068, or non-thermal, synchrot

C. R. Gwinn, M. C. Britton, J. E. Reynolds, D. L. Jauncey

We present measurements of the size of the Vela pulsar in 3 gates across the pulse, from observations of the distribution of intensity. We calculate the effects on this distribution of noise in the observing system, and measure and remove it using observations of a strong continuum source. We also calculate and remove the expected effects of averaging in tim

P. Vignati, S. Molendi, G. Matt, M. Guainazzi

The direct nuclear X-ray emission of the ultraluminous IRAS galaxy NGC 6240 has been observed for the first time by BeppoSAX. It is seen through an absorber with N_H=2*10^{24} cm^{-2}. The 2-10 keV X-ray luminosity >10^{44} erg s^{-1} definitely proves that a powerful AGN is hosted in this galaxy, despite the LINER optical appearance. Assuming the typical L_

Guido De Marchi, Francesco Paresce, Luigi Pulone

We have investigated the properties of the stellar mass function in the globular cluster NGC6397 using a large set of HST observations that include WFPC2 images in V and I, obtained at ~4&#39; and 10&#39; radial distances, and a series of deep images in the J and H bands obtained with the NIC2 and NIC3 cameras of NICMOS pointed to regions located ~4.5&#39; a

M. C. Rabello-Soares, J. Christensen-Dalsgaard, C. S. Rosenthal, M. J. Thompson

Despite the strong evidence that the peaks in the spectrum of solar oscillations are asymmetric, most determinations of mode frequencies have been based on fits of symmetric Lorentzian profiles to the Fourier or power spectra of oscillation time strings. The systematic errors resulting from neglecting the line asymmetry could have serious effects on inversio

A. D. Kaminker, P. Haensel

We study neutrino energy emission rates (emissivities) due to electron bremsstrahlung produced by $ee$ and $ep$ collisions in the superfluid neutron star cores. The neutrino emission due to $ee$ collisions is shown to be the dominant neutrino reaction at not too high temperatures ($T \la 10^8$ K) in dense matter if all other neutrino reactions involving nucl

Heinz Oberhummer, Attila Csoto, Helmut Schlattl

Through the triple-alpha process occurring in red giant stars the bulk of the carbon existing in our universe is produced. We calculated the change of the triple-alpha reaction rate for slight variations of the nucleon-nucleon force using a microscopic 12-body model. Stellar model calculations for a low-mass, intermediate-mass and massive star using the diff

Jason K. Perry, Jamil Tahir-Kheli

We show that the unusual observations of a pseudogap in the normal state of underdoped Bi_2Sr_2CaCu_2O_8+delta (BiSCO) using angle resolved photoemission spectroscopy (ARPES) is consistent with a new band structure for the cuprate superconductors in which the x2-y2 and z2 bands are seen to cross at the Fermi level. Limitations in the experimental method prev

Arnold Neumaier

The best mathematical arguments against a realistic interpretation of quantum mechanics - that gives definite but partially unknown values to all observables - are analysed and shown to be based on reasoning that is not compelling. This opens the door for an interpretation that, while respecting the indeterministic nature of quantum mechanics, allows to spea

Edgar Paternina

This is the third one of three papers I have presented as an application of the Basic Unit System concept, a complex mathematical unit presented in The Basic Unit System concept and The Principle of Synergy. In this case this Bus concept is used as a powerful tool to obtain again those gravitational field equations of normal planets, deviation from them as t

Dale G. Fried

This thesis describes the observation and study of Bose-Einstein condensation of a trapped, dilute gas of atomic hydrogen. The condensate and normal gas are studied by two-photon spectroscopy of the 1S-2S transition. We condense over 10^9 atoms per second for several seconds, and the peak condensate density is around 5x10^15 cm^-3. Topics covered in the thes

Zoltan Ligeti

The determination of |Vcb| and |Vub| from semileptonic B decay is reviewed with a critical discussion of the theoretical uncertainties. Future prospects and limitations are also discussed.

Zenro Hioki

The energy spectra of the lepton(s) in eebar --> ttbar --> l^{+-}X/ l^+l^- X&#39; at next linear colliders (NLC) are analyzed a model-independent way for arbitrary longitudinal beam polarizations as a general test of possible anomalous top-quark couplings.

M. Musakhanov

In this talk we discuss an improvement of the Diakonov-Petrov QCD Effective Action. We propose the Improved Effective Action, which is derived on the basis of the Lee-Bardeen results for the quark determinant in the instanton field. The Improved Effective Action provides proper account of the current quark masses, which is particularly important for strange

P. Pennanen, C. Michael, A. M. Green

The potential between static-light mesons forming a meson-meson or a meson-antimeson system is calculated in quenched and unquenched SU(3) gauge theory. We use the Sheikholeslami-Wohlert action and statistical estimators of light quark propagators with maximal variance reduction. The dependence of the potentials on the light quark spin and isospin and the ef

Bertrand Duplantier

The multifractal (MF) distribution of the electrostatic potential near any conformally invariant fractal boundary, like a critical O(N) loop or a $Q$ -state Potts cluster, is solved in two dimensions. The dimension $\hat f(θ)$ of the boundary set with local wedge angle $θ$ is $\hat f(θ)=\fracπθ -\frac{25-c}{12} \frac{(π-θ)^2}{θ(2π-θ)}$, with $c$ the central

M. Kang, K. Yasutani, M. Kaburagi

The phase diagram of adsorbate-induced row-type-alignments, such as missing-row reconstructions induced by adsorbate-atoms on the FCC(110) surface, is calculated by the Blume-Emmery-Griffiths (BEG) model. In the model, we introduce adatom-adatom and dipole-dipole interactions between nearest-neighbor (NN) and next-nearest-neighbor (NNN) rows. The calculation

H. W. Diehl, M. Smock

Continuum models with critical end points are considered whose Hamiltonian ${\mathcal{H}}[ϕ,ψ]$ depends on two densities $ϕ$ and $ψ$. Field-theoretic methods are used to show the equivalence of the critical behavior on the critical line and at the critical end point and to give a systematic derivation of critical-end-point singularities like the thermal sing

K. Moon, K. Mullen

We numerically study the interacting quantum Hall skyrmion system based on the Chern-Simons action. By noticing that the action is invariant under global spin rotations in the spin space with respect to the magnetic field direction, we obtain the low-energy effective action for a many skyrmion system. Performing extensive molecular dynamics simulations, we e

D. B. Saakian

In spin glass models one can remove minimization of free energy by some order parameter. One can consider hierarchy of order parameters. It is possible to divide energy among these parts. We can consider relaxation process in glass system phenomonologically, as exchange of energy between 2 parts. It is possible to identify trap points in phase space. We sugg

Charles L. Bennett

Currently three imaging spectrometer architectures, tunable filter, dispersive, and Fourier transform, are viable for imaging the universe in three dimensions. There are domains of greatest utility for each of these architectures. The optimum choice among the various alternative architectures is dependent on the nature of the desired observations, the maturi

Ying-Jer Kao, Qimiao Si, K. Levin

We study the evolution of the neutron cross-section with variable frequency $ω$ and fixed $T$ below $T_c$ in two different cuprate families. Our calculations, which predominantly probe the role of d-wave pairing, lead to generic features, independent of Fermi surface shapes. Among our findings, reasonably consistent with experiment, are (i) for $ω$ near the

F. Rami, Y. Leifels, B. de Schauenburg, A. Gobbi

Four different combinations of $^{96}_{44}$Ru and $^{96}_{40}$Zr nuclei, both as projectile and target, were investigated at the same bombarding energy of 400$A$ MeV using a $4 π$ detector. The degree of isospin mixing between projectile and target nucleons is mapped across a large portion of the phase space using two different isospin-tracer observables, th

C. Weth, P. Meszaros, T. Kallman, M. J. Rees

We calculate the X-ray/UV spectral line signatures expected from the interaction of a gamma-ray burst afterglow and a dense pre-burst environment produced by the progenitor. We explore the conditions under which Fe line and edge equivalent widths of $\sim$ 1 keV can arise, and discuss the possibility of gaining information about possible progenitor scenarios

Zygmunt Lalak, Steven Thomas

We investigate the formation of dynamical gaugino condensates and supersymmetry breaking in the compactifications of Horava-Witten theory with perturbative nonstandard embeddings. Specific models are considered where the underlying massless charged states of the condensing sector are determined by the spectra of $Z_2 \times Z_2 $ and $Z_4 $ orbifolds with no

Antonio Scala, Francis W. Starr, Emilia La Nave, Francesco Sciortino

We calculate the configurational entropy S_conf for the SPC/E model of water for state points covering a large region of the (T,rho) plane. We find that (i) the (T,rho) dependence of S_conf correlates with the diffusion constant and (ii) that the line of maxima in S_conf tracks the line of density maxima. Our simulation data indicate that the dynamics are st

Kaori Fukuda, Masato Okado, Yasuhiko Yamada

The box ball system is studied in the crystal theory formulation. New conserved quantities and the phase shift of the soliton scattering are obtained by considering the energy function (or $H$-function) in the combinatorial $R$-matrix.

R. P. Martínez-y-Romero, H. N. Núñez-Yépez, A. L. Salas-Brito

The Dirac oscillator is an exactly soluble model recently introduced in the context of many particle models in relativistic quantum mechanics. The model has been also considered as an interaction term for modelling quark confinement in quantum chromodynamics. These considerations should be enough for demonstrating that the Dirac oscillator can be an excellen

Valeri V. Dvoeglazov

Zero-energy solutions of Maxwell&#39;s equations have been discovered and re-discovered many times in this century. In this comment we show that the paper by A. E. Chubykalo (which, in fact, also comments on the recent papers) did not explain physical interpretation of this solution and it used doubtful (up-to-date) postulates. Different explanations of the

Edgar Paternina

This is the second of three papers I will present as an application of the Basic Unit System concept, a complex mathematical unit presented in The Basic Unit System concept and The Principle of Synergy. In this case this Bus concept is used as a powerful tool to obtain again the Lorentz Transformation Groups of equations, and then to present the emergent pro

Indrajit Chakrabarty

In this article, I present an elementary introduction to the theory of gravitational waves. This article is meant for students who have had an exposure to general relativity, but, results from general relativity used in the main discussion have been derived and discussed in the appendices. The weak gravitational field approximation is first considered and th

Nima Arkani-Hamed, Savas Dimopoulos, John March-Russell

In theories with TeV string scale and sub-millimeter extra dimensions the attractive picture of logarithmic gauge coupling unification at $10^{16}$ GeV is seemingly destroyed. In this paper we argue to the contrary that logarithmic unification {\it can} occur in such theories. The rationale for unification is no longer that a gauge symmetry is restored at sh

Chueng-Ryong Ji, Ho-Meoyng Choi

We investigate the electroweak form factors and semileptonic decay rates of mesons using the constituent quark model based on the light-front degrees of freedom. Our results demonstrate the broader applicability of light-front approach including the timelike region of exclusive processes.

Ho-Meoyng Choi, Chueng-Ryong Ji

We investigate the form factors and decay rates of exclusive $0^{-}\to0^{-}$ semileptonic meson decays using the constituent quark model based on the light-front quantization. Our model is constrained by the variational principle for the linear plus Coulomb interaction motivated by QCD. Our numerical results are in a good agreement with the available experim

N. Haba, Y. Matsui, N. Okamura, M. Sugiura

There are physical Majorana phases in the lepton flavor mixing matrix when neutrinos are Majorana fermions. In the case of two degenerate neutrinos, the physical Majorana phase plays the crucial role for the stability of the maximal flavor mixing between the second and the third generations against quantum corrections. The physical Majorana phase of $π$ guar

T. G. Kovács, E. T. Tomboulis

A lower bound on the string tension for large beta in SU(2) LGT is derived. The derivation is from first principles and bounds the string tension from below by the expectation for the excitation of a single `tagged&#39; thick vortex winding around the lattice. Thus confinement follows if this expectation remains nonvanishing at large beta. Numerical simulati