August 1999 arXiv papers — page 10

A. Derevianko, O. Hemmers, S. Oblad, P. Glans

Second-order [O(k^2), k=omega/c] nondipole effects in soft-x-ray photoemission are demonstrated via an experimental and theoretical study of angular distributions of neon valence photoelectrons in the 100--1200 eV photon-energy range. A newly derived theoretical expression for nondipolar angular distributions characterizes the second-order effects using four

D. M. Snyder

Though Einstein and other physicists recognized the importance of an observer being at rest in an inertial reference frame for the special theory of relativity, the supporting psychological structures were not discussed much by physicists. On the other hand, Rock, a psychologist, wrote of the factors involved in the perception of motion, including one's

D. M. Snyder

Gravitational force manifested in its affect on rotational velocity is what indicates the presence of dark matter in individual galaxies. Newtonian mechanics is generally used to derive the relationship between rotational velocity and gravitational force. In Newtonian mechanics, mass is associated with gravitation. At the same time, in such galaxies there ap

R. A. Arndt, I. I. Strakovsky, R. L. Workman, M. M. Pavan

We summarize results obtained in our studies of the pion-nucleon coupling constant. Several different techniques have been applied to pi-N and NN elastic scattering data, and the existing database for single-pion photoproduction. The most reliable determination comes from pi-N elastic scattering. The sensitivity in this reaction was found to be greater, by a

J. C. Lemm, J. Uhlig

A new method is presented to reconstruct the potential of a quantum mechanical many-body system from observational data, combining a nonparametric Bayesian approach with a Hartree-Fock approximation. A priori information is implemented as a stochastic process, defined on the space of potentials. The method is computationally feasible and provides a general f

Peter Braun-Munzinger

We discuss current plans for experiments with ultra-relativistic nuclear collisions with heavy beams at LHC energy ($\sqrt{s} = 5.5$ TeV/nucleon pair). Emphasis will be placed on processes which are unique to the LHC program. They include event-by-event interferometry, complete spectroscopy of the $Υ$ resonances, and open charm and open beauty measurements.

Pavel Exner

We discuss discuss spectral and scattering properties of a particle confined to a straight Dirichlet tube in $\mathbb{R}^3$ with a family of point interactions.

P. Spallanzani

The approaches to quantum field theories based in the so called loop representation deserved much attention recently. In it, closed curves and holonomies around them play a central role. In this framework the group of loops and the group of hoops have been defined, the first one consisting in closed curves quotient with the equivalence relation that identifi

Andreas Defant, Carsten Michels

Within the theory of complex interpolation and theta-Hilbert spaces we extend classical results of Kwapien on absolutely (r,1)-summing operators on l_1 with values in l_p as well as their natural extensions for mixing operators invented by Maurey. Furthermore, we show that for 1<p<2 every operator T on l_1 with values in theta-type 2 spaces, theta=2/p&#39;,

Masanori Asakura

In this paper, we define a certain Hodge-theoretic structure for an arbitrary variety X over the complex number field by using the theory of mixed Hodge module due to Morihiko Saito. We call it an arithmetic Hodge structure of X. It is shown that extension groups of arithmetic Hodge structure do not vanish even for degree $\geq2$. Moreover, we define higher

Atsushi Moriwaki

Let K be a finitely generated field over Q, and A an abelian variety over K. Let <, > : A(K^a) x A(K^a) --> R be an arithmetic height pairing on A, where K^a is the algebric closure of K. For x_1,..., x_l \in A(K^a), we denote det(<x_i, x_j>) by d(x_1,..., x_l). Let G be a subgroup of finite rank in A(K^a), and X a subvariety of A_{K^a}. Fix a basis {g_1,...

Kazuyoshi Mori

We present a parameterization of the stabilizing controllers over commutative rings. In the classical case, that is, in the case where there exist the right-/left-coprime factorizations of the given plant, the stabilizing controllers can be parameterized by the method called ``Youla-Kucera-parameterization&#39;&#39;. However, it is known that there exist mod

Patricio Gaete, Iván Schmidt

Features of screening and confinement are reviewed in two-dimensional quantum electrodynamics (QED2). Our discussion is carried out using the gauge-invariant but path-dependent variables formalism. This alternative and useful approach exploits the rich structure of the electromagnetic cloud or dressing around static fermions in a straightforward and simple w

Christos Kokorelis

We discuss aspects of the non-standard version of F-theory based on the arithmetic of torsion points on elliptic curves. We construct new F-theory vacua in 8 dimensions...

E. d&#39;Emilio, S. Micciche

The freedom one has in constructing locally gauge invariant charged fields in gauge theories is analyzed in full detail and exploited to construct, in QED, an electron field whose two-point function W(p), up to the fourth order in the coupling constant, is normalized with on-shell normalization conditions and is, nonetheless, infra-red finite; as a consequen

Wei-Min Zhang

Coherent states have three main properties: coherence, overcompleteness and intrinsic geometrization. These unique properties play fundamental roles in field theory, especially, in the description of classical domains and quantum fluctuations of physical fields, in the calculations of physical processes involving infinite number of virtual particles, in the

Mario E. Gomez

U(1)-family symmetries have led to successful predictions of the fermion mass spectrum and the mixing angles of the hadronic sector. In the context of the supersymmetric unified theories, they further imply a non-trivial mass structure for the scalar partners, giving rise to new sources of flavour violation. While tau->mu gamma decays are mostly expected to

Alexander L. Kagan, Matthias Neubert

We show that in supersymmetric extensions of the Standard Model gluino box diagrams can yield a large Delta(I)=3/2 contribution to s->d+q(bar)+q FCNC processes, which may induce a sizable CP-violating contribution to the I=2 isospin amplitude in K->pi+pi decays. This contribution only requires moderate mass splitting between the right-handed up- and down-squ

Lev Kofman

In this talk recent developments of the theory of preheating after inflation are briefly reviewed. In inflationary cosmology, the particles constituting the Universe are created after inflation due to their interaction with moving inflaton field(s) in the process of reheating. In inflationary models motivated by supergravity, both bosons and fermions are cre

S. I. Bityukov, N. V. Krasnikov

We propose a method to estimate the probability of new physics discovery in future high energy physics experiments. Physics simulation gives both the average numbers $<N_b>$ of background and $<N_s>$ of signal events. We find that the proper definition of the significance is $S_{12} = \sqrt{<N_s>+<N_b>} - \sqrt{<N_b>}$ in comparison with often used significa

Gino Isidori

We present a brief overview of rare K decays, emphasizing the different role of Standard Model and possible New Physics contributions in various channels.

S. Y. Choi

We re-investigate the neutralino-nucleus elastic scattering as a promising dark matter detection mechanism including contributions from the scalar-pseudoscalar mixing of neutral Higgs states and the induced phase between two Higgs doublets due to the CP-violating phases of the scalar top and bottom sectors in the minimal supersymmetric standard model. The sp

J. March-Russell, H. Murayama, A. Riotto

Primordial Big-Bang Nucleosynthesis (BBN) tightly constrains the existence of any additional relativistic degrees of freedom at that epoch. However a large asymmetry in electron neutrino number shifts the chemical equilibrium between the neutron and proton at neutron freeze-out and allows such additional particle species. Moreover, the BBN itself may also pr

Andrzej J. Buras

We review the present theoretical status of the CP violating ratio epsilon&#39;/epsilon in the Standard Model (SM) and confront its estimates with the most recent data. In particular we review the present status of the most important parameters m_s, B_6^(1/2), B_8^(3/2), Λ_MSbar and Omega_{η+η&#39;}. While the sign and the order of magnitude of SM estimates

S. A. Larin

The method of expansion of integrals in external parameters is suggested. It is quite universal and works for Feynman integrals both in Euclidean and Minkowski regions of momenta.

Leonid L. Frankfurt, Gerald A. Miller, Misak M. Sargsian, Mark I. Strikman

Photon absorption by a quark in one nucleon followed by its high momentum transfer interaction with a quark in the other may produce two nucleons with high relative momentum. We sum the relevant quark rescattering diagrams, to show that the scattering amplitude depends on a convolution between the large angle $pn$ scattering amplitude, the hard photon-quark

Sinead Ryan

Lattice calculations of the mass of the strange quark are reviewed. In particular, the reason for the spread in values is explained with emphasis on the effects that recently implemented improvements have had on the lattice determinations.

S. Bertolini

I discuss the comparison of the current theoretical calculations of epsilon&#39;/epsilon with the experimental data. Lacking reliable ``first principle&#39;&#39; calculations, phenomenological approaches may help in understanding correlations among different contributions and available experimental data. In particular, in the chiral quark model approach the

Michael Creutz

The QCDSP machines were designed for lattice gauge calculations. For planning it is crucial to explore this architecture for other computationally intensive tasks. Here I describe an implementation of a simple message passing scheme. With the objective being simplicity, I introduce a small number of generic functions for manipulating a large data set spread

Ting-Wai Chiu

According to the necessary requirements for a chirally symmetric Dirac operator, we present a systematic construction of such operators. We formulate a criterion for the hermitian operator which enters the construction such that the doubled modes are decoupled even at finite lattice spacing.

E. -M. Ilgenfritz, Werner Kerler, H. Stüben

We study the improvement of simulations of QCD with dynamical Wilson fermions by combining the Hybrid Monte Carlo algorithm with parallel tempering. As an indicator for decorrelation we use the topological charge.

Gunnar S. Bali

Potentials between two static sources in various representations of the SU(3) gauge group are determined on anisotropic 3+1 dimensional lattices. Strong evidence in favour of &#34;Casimir scaling&#34; is found.

M. Faber, J. Greensite, S. Olejnik, D. Yamada

We present several new results which pertain to the successes of center projection in maximal center gauge (MCG). In particular, we show why any center vortex, inserted &#34;by hand&#34; into a thermalized lattice configuration, will be among the set of vortices found by the center projection procedure. We show that this &#34;vortex-finding property&#34; is

M. A. Yurishchev

Different phenomenological RG transformations based on scaling relations for the derivatives of the inverse correlation length and singular part of the free-energy density are considered. These transformations are tested on the 2D square Ising and Potts models as well as on the 3D simple-cubic Ising model. Variants of RG equations yielding more accurate resu

A. J. Schwartz

Fermilab experiment E791 studied weak decays of D+, D_s, and D^0 mesons produced in collisions of 500 GeV/c negative pions with Pt and C targets. The experiment collected over 200,000 fully reconstructed charm decays. Four recent results are discussed here: (a) measurement of the form factor ratios V/A_1, A_2/A_1, and A_3/A_1 in D->K*-l-nu and Ds->phi-l-nu d

P. Hajicek, J. Kijowski

The symplectic geometry of a broad class of generally covariant models is studied. The class is restricted so that the gauge group of the models coincides with the Bergmann-Komar group and the analysis can focus on the general covariance. A geometrical definition of gauge fixing at the constraint manifold is given; it is equivalent to a definition of a backg

L. C. Garcia de Andrade

Two classes of metrics obtained from non-Riemannian gravitational collapse are presented.The first is the Taub planar symmetric exact solutions of Einstein-Cartan field equations of gravity describing torsion walls which are obtained from gravitational collapse of time dependent perturbation of Riemannian Taub symmetric solutions of General Relativity.The se

V. Hizhnyakov, D. Nevedrov, E. Sigmund

Localized modes of large amplitudes in nonlinear lattices are considered. The applied method allows the reduction of nonlinear problem to a linear inverse problem of phonons scattering on a local potential. The method is efficient in the case of strongly localized modes. Analytical description of such modes in monatomic chain is given. Results of numerical c

N. Bulut

The effects of nonmagnetic impurities on the neutron scattering intensity are studied for a model of the copper oxide layers in the normal state. The contribution to the Q=(pi,pi) neutron scattering intensity from processes involving the scattering of the spin fluctuations from an impurity with large momentum transfers are calculated within the random phase

F. C. Alcaraz, R. Z. Bariev

Two new one-dimensional fermionic models depending on two independent parameters are formulated and solved exactly by the Bethe-ansatz method. These models connect continuously the integrable Hubbard and supersymmetric t-J models.

D. Sénéchal

This is an expanded version of a lecture given at the {\it Workshop on Theoretical Methods for Strongly Correlated Fermions}, held at the {\it Centre de Recherches Mathématiques}, in Montréal, from May 26 to May 30, 1999. After general comments on the relevance of field theory to condensed matter systems, the continuum description of interacting electrons in

T. Lofwander, G. Johansson, G. Wendin

We investigate the dc current-voltage characteristics of d-wave Josephson junctions, where the barrier at the interface may have arbitrary strength. Dividing the current into n-particle currents $I_n$ (n integer), we can explicitly show which physical processes are responsible for the subharmonic gap structure (SGS). For orientations where midgap states (MGS

F. Ghaboussi

We present a two dimensional model of IQHE in accord with the cyclotron motion. The quantum equation of the QHE curve and a new definition of filling factor are also given.

Sigurdur I. Erlingsson, Andrei Manolescu, Vidar Gudmundsson

We calculate the orbital magnetization of a confined 2DEG as a function of the number of electrons in the system. Size effects are investigated by systematically increasing the area of the confining region. The results for the finite system are compared to an infinite one, where the magnetization is calculated in the thermodynamic limit. In all calculations

I. V. Schweigert, V. A. Schweigert, F. M. Peeters

The stability and melting transition of a single layer and a bilayer crystal consisting of charged particles interacting through a Coulomb or a screened Coulomb potential is studied using the Monte-Carlo technique. A new melting criterion is formulated which we show to be universal for bilayer as well as for single layer crystals in the case of (screened) Co

V. A. Schweigert, F. M. Peeters

Using an expansion of the order parameter over the eigenfunctions of the linearized first Ginzburg-Landau (GL) equation, we obtain numerically the saddle points of the free energy separating the stable states with different number of vortices. In contrast to known surface and geometrical barrier models, we find that in a wide range of magnetic fields below t

P. Cain, R. A. Roemer, M. Schreiber

We examine the localization properties of the three-dimensional (3D) Anderson Hamiltonian with off-diagonal disorder using the transfer-matrix method (TMM) and finite-size scaling (FSS). The nearest-neighbor hopping elements are chosen randomly according to $t_{ij} \in [c-1/2, c + 1/2]$. We find that the off-diagonal disorder is not strong enough to localize

K. Hoshi, Y. Hatsugai

The Bethe ansatz (BA) equations for the two-dimensional Bloch electrons in a uniform magnetic field are treated in the weak field limit. We have calculated energies near the lower boundary of the energy spectrum up to the first nontrivial order. It corresponds to calculating a finite size correction for the excitation energies of the BA solvable lattice mode

Erik Aurell, Paolo Muratore-Ginanneschi

We study long-term growth-optimal strategies on a simple market with linear proportional transaction costs. We show that several problems of this sort can be solved in closed form, and explicit the non-analytic dependance of optimal strategies and expected frictional losses of the friction parameter. We present one derivation in terms of invariant measures o

P. L. Krotkov

The influence of an external electric field on the spin dynamics of an electrically neutral Fermi liquid is considered, the mechanism of such an influence being the relativistic spin-orbital interaction. As a result, Leggett&#39;s equations for the spin dynamics of weakly polarized Fermi liquids are generalized to the case of non-zero external electric field

Youngki Lee, Jose S. Andrade, Sergey V. Buldyrev, Nikolay V. Dokholyan

We study traveling time and traveling length for tracer dispersion in porous media. We model porous media by two-dimensional bond percolation, and we model flow by tracer particles driven by a pressure difference between two points separated by Euclidean distance $r$. We find that the minimal traveling time $t_{min}$ scales as $t_{min} \sim r^{1.40}$, which

H. Courtois, P. Charlat, Ph. Gandit, D. Mailly

In a mesoscopic metal in proximity with a superconductor, the electronic conductance is enhanced in a very energy-sensitive way. In this paper, we discuss the spectral conductance of a proximity superconductor from both the theoretical and experimental point of view. The dependence of the spectral conductance on the phase-breaking length, gap of the supercon

T. Bartsch, J. Main, G. Wunner

Gutzwiller&#39;s trace formula allows interpreting the density of states of a classically chaotic quantum system in terms of classical periodic orbits. It diverges when periodic orbits undergo bifurcations, and must be replaced with a uniform approximation in the vicinity of the bifurcations. As a characteristic feature, these approximations require the incl

Jean-Pierre Eckmann, Omri Gat

We study the implications of translation invariance on the tangent dynamics of extended dynamical systems, within a random matrix approximation. In a model system, we show the existence of hydrodynamic modes in the slowly growing part of the Lyapunov spectrum, which are analogous to the hydrodynamic modes discovered numerically by [Dellago, Ch., Posch, H.A.,

Krzysztof Gawedzki

This is an introductory course on fully developed turbulence. It discusses: in Lecture 1: the Navier Stokes equations, existence of solutions, statistical description, energy balance and cascade picture; in Lecture 2: the Kolmogorov theory of three-dimensional turbulence versus intermittency, the Kraichnan-Batchelor theory of two-dimensional turbulence; in L

Cristina Chiappini, Francesca Matteucci, Paolo Padoan

In this work we explore the effects of adopting initial mass functions (IMFs) variable in time on the chemical evolution of the Galaxy. In order to do that we adopt a chemical evolution model which assumes two main infall episodes for the formation of the Galaxy and which proved to be successful in reproducing the majority of the observational constraints, a

Maarten Schmidt

We use a homogeneous sample of gamma-ray bursts (GRB) extracted from 5.9 years of BATSE DISCLA data (astro-ph/9908190) and a variety of broken power-law luminosity functions to derive GRB luminosities and space densities. Luminosity functions that are narrow or exhibit no density evolution produce expected redshift distributions that are incompatible with th

B. Boroson, T. Kallman, S. Vrtilek, J. Raymond

The UV emission lines of Hercules X-1, resolved with the HST GHRS and STIS, can be divided into broad (FWHM 750 km/s) and narrow (FWHM 150 km/s) components. The broad lines can be unambiguously identified with emission from an accretion disk which rotates prograde with the orbit. The narrow lines, previously identified with the X-ray illuminated atmosphere o

I. Dominguez, P. Hoeflich

Detailed models of the explosion of a white dwarf, which include self-consistent calculations of the light curve and spectra, provide a link between observational quantities and the underlying explosion.These calculations assume spherical geometry and are based on parameterized descriptions of the burning front during the deflagration phase. Recently, first

Thomas H. Puzia, Markus Kissler-Patig, Jean P. Brodie, John P. Huchra

The age difference between the two main globular cluster sub-populations in the Virgo giant elliptical galaxy, NGC 4472 (M 49), has been determined using HST WFPC2 images in the F555W and F814W filters. Accurate photometry has been obtained for several hundred globular clusters in each of the two main sub-populations, down to more than one magnitude below th

F. Arqueros, The HEGRA Collaboration

Measurements of the lateral distribution of Cherenkov photons with the wide-angle atmospheric Cherenkov light detector array AIROBICC and of the charged particle lateral distribution with the scintillator matrix of the HEGRA air-shower detector complex in air showers are reported. With the atmospheric shower-front sampling technique these detectors measure t

Lewis Ball, J. G. Kirk

We investigate the effects of inverse Compton scattering by electrons and positrons in the unshocked winds of rotationally-powered binary pulsars. This process can scatter low energy target photons to produce gamma rays with energies from MeV to TeV. The binary radio pulsars PSR B1259-63 and PSR J0045-73 are both in close eccentric orbits around bright main

P. A. Crowther, A. Pasquali, O. De Marco, W. Schmutz

We use WR124 (WN8h) and its associated nebula M1-67, to test theoretical non-LTE models for Wolf-Rayet (WR) stars. Lyman continuum ionizing flux distributions derived from a stellar analysis of WR124, are compared with nebular properties via photo-ionization modelling. Our study demonstrates the significant role that line blanketing plays in affecting the Ly

Eliot Quataert, Ramesh Narayan

Cooling flows in galaxy clusters and isolated elliptical galaxies are a source of mass for fueling accretion onto a central supermassive black hole. We calculate the dynamics of accreting matter in the combined gravitational potential of a host galaxy and a central black hole assuming a steady state, spherically symmetric flow (i.e., no angular momentum). Th

Shijun Yoshida, Umin Lee

We investigate inertial mode oscillations of slowly and uniformly rotating, isentropic, Newtonian stars. Inertial mode oscillations are induced by the Coriolis force due to the star&#39;s rotation, and their characteristic frequencies are comparable with the rotation frequency $Ω$ of the star. So called r-mode oscillations form a sub-class of the inertial mo

Jorick S. Vink, Alex de Koter, Henny J. G. L. M. Lamers

We study the origin of the observed bi-stability jump in the terminal velocity of the winds of supergiants near spectral type B1. To this purpose, we have calculated a grid of wind models and mass-loss rates for these stars. The models show that the mass-loss rate &#39;jumps&#39; by a factor of five around spectral type B1. Up to now, a theoretical explanati

M. Seigar

We have obtained HST_NICMOS images for 72 nearby spiral galaxy bulges in the H-band. These data show that galaxies with regular bulges have steeper nuclear cusps than galaxies with irregular bulges. We also show that galaxies with regular bulges fall on the same part of the (<γ>, magnitude)-diagram as elliptical galaxies. This implies that early-type spiral

Y. Uchihori, M. Nagano, M. Takeda, M. Teshima

The arrival directions of extremely high energy cosmic rays (EHECR) above $4\times10^{19}$ eV, observed by four surface array experiments in the northern hemisphere,are examined for coincidences from similar directions in the sky. The total number of cosmic rays is 92.A significant number of double coincidences (doublet) and triple coincidences (triplet) are

Laura Ferrarese, Jeremy R. Mould, Robert C. Kennicutt,, John Huchra

A Cepheid-based calibration is derived for four distance indicators that utilize stars in the old stellar populations: the tip of the red giant branch (TRGB), the planetary nebula luminosity function (PNLF), the globular cluster luminosity function (GCLF) and the surface brightness fluctuation method (SBF). The calibration is largely based on the Cepheid dis

Bogdan A. Dobrescu

We analyze a composite Higgs model with the minimal content that allows a light Standard-Model-like Higgs boson, potentially just above the current LEP limit. The Higgs boson is a bound state made up of the top quark and a heavy vector-like quark. The model predicts that only one other bound state may be lighter than the electroweak scale, namely a CP-odd ne

A. Brandhuber, K. Sfetsos

The four-dimensional Minkowski space-time is considered as a three-brane embedded in five dimensions, using solutions of five-dimensional supergravity. These backgrounds have a string theoretical interpretation in terms of D3-brane distributions. By studying linear fluctuations of the graviton we find a zero-mode representing the massless graviton in four-di

Nicole M. Lloyd-Ronning, Vahe' Petrosian, Robert S. Mallozzi

We present results of correlation studies, examining the association between the peak of the nu F_nu spectrum of gamma ray bursts, E_p, with the burst's energy fluence and photon peak flux. We discuss methods to account for data truncation in E_p and fluence or flux when performing the correlation analyses. However, because bursts near the detector threshold

M. A. Halasz, J. C. Osborn, M. A. Stephanov, J. J. M. Verbaarschot

We apply the Glasgow method for lattice QCD at finite chemical potential to a schematic random matrix model (RMM). In this method the zeros of the partition function are obtained by averaging the coefficients of its expansion in powers of the chemical potential. In this paper we investigate the phase structure by means of Glasgow averaging and demonstrate th

Michael Martin Nieto

Isolated electrons resting above a helium surface are predicted to have a bound spectrum corresponding to a one-dimensional hydrogen atom. But in fact, the observed spectrum is closer to that of a quantum-defect atom. Such a model is discussed and solved in analytic closed form.

C. A. Scharf, K. Jahoda, M. Treyer, O. Lahav

The hard X-ray (>2 keV) emission of the local and distant Universe as observed with the HEAO1-A2 experiment is reconsidered in the context of large scale cosmic structure. Using all-sky X-ray samples of AGN and galaxy clusters we remove the dominant local X-ray flux from within a redshift of ~ 0.02. We evaluate the dipolar and higher order harmonic structure

R. R. Metsaev

Light cone gauge manifestly supersymmetric formulations of type IIB 10-dimensional supergravity in $AdS_5 \times S^5$ background and related boundary conformal field theory representations are developed. A precise correspondence between the bulk fields of IIB supergravity and the boundary operators is established. The formulations are given entirely in terms

H. Kleinert

For systems exhibiting a second-order phase transition with a spontaneously broken continuous O(N)-symmetry at low temperature, we give a criterion for judging at which temperature T_K long-range directional fluctuations of the order field destroy the order when approaching the critical temperature from below. The temperature T_K lies always significantly be

Gennaro Corcella, Michael H. Seymour

The production of vector bosons at present and future hadron colliders will provide a crucial test for QCD and Standard Model physics. In this paper we improve parton shower simulations of Drell-Yan processes by implementing matrix-element corrections to the initial-state radiation. We apply our work to the HERWIG Monte Carlo event generator and compare our

G. Eyal, A. Masiero, Y. Nir, L. Silvestrini

We discuss the supersymmetric contribution to $ε&#39;/ε$ in various supersymmetric flavor models. We find that in alignment models the supersymmetric contribution could be significant while in heavy squark models it is expected to be small. The situation is particularly interesting in models that solve the flavor problems by either of the above mechanisms an

Thorsten Droese, Cristiane Morais-Smith

Thermal activation and macroscopic quantum tunneling in current-biased discrete Josephson transmission lines are studied theoretically. The degrees of freedom under consideration are the phases across the junctions which are coupled to each other via the inductances of the system. The resistively shunted junctions that we investigate constitute a system of N

Aristophanes Dimakis, Folkert Muller-Hoissen

A gauged bi-differential calculus over an associative (and not necessarily commutative) algebra A is an N-graded left A-module with two covariant derivatives acting on it which, as a consequence of certain (e.g., nonlinear differential) equations, are flat and anticommute. As a consequence, there is an iterative construction of generalized conserved currents

Kikuo Harigaya

Magnetic impurity effects on metallic carbon nanotubes are studied theoretically. The resolvent method for the multi channel Kondo effect is applied to the band structure of the kp perturbation hamiltonian in the limit of the infinite onsite repulsion at the impurity site. We discuss the local non-Fermi liquid behavior at temperatures lower than the Kondo te

B. Ramstein, C. A. Mosbacher, D. Bachelier, I. Berquist

The inclusive 2H(3He,t) reaction has been studied at 2 GeV for energy transfers up to 500 MeV and scattering angles from 0.25 up to 4 degrees. Data are well reproduced by a model based on a coupled-channel approach for describing the NN and N Delta systems. The effect of final state interaction is important in the low energy part of the spectra. In the delta

Peter Ashwin, Xin-Chu Fu, Takashi Nishikawa, Karol Zyczkowski

We analyze a class of piecewise linear parabolic maps on the torus, namely those obtained by considering a linear map with double eigenvalue one and taking modulo one in each component. We show that within this two parameter family of maps, the set of noninvertible maps is open and dense. For cases where the entries in the matrix are rational we show that th

Lu-Ming Duan, G. Giedke, J. I. Cirac, P. Zoller

An inseparability criterion based on the total variance of a pair of Einstein-Podolsky-Rosen type operators is proposed for continuous variable systems. The criterion provides a sufficient condition for entanglement of any two-party continuous variable states. Furthermore, for all the Gaussian states, this criterion turns out to be a necessary and sufficient

J. Gegelia, G. Japaridze

On the simple model of interacting massless and heavy scalar fields it is demonstrated that the technique of heavy baryon chiral perturbation theory reproduces the results of relativistic theory. Explicit calculations are performed for diagrams including two-loops.

A. Actor, I. Bender, J. Reingruber

This article presents a Hamiltonian lattice formulation of static Casimir systems at a level of generality appropriate for an introductory investigation. Background structure - represented by a lattice potential V(x) - is introduced along one spatial direction with translation invariance in all other spatial directions. Following some general analysis two sp

Yu. N. Morokov

The electron-diffraction pattern at a nonfluorescent target was observed by Schwarz under attempts to modulate an electron beam by laser light. The pattern was of the same color as the laser light. The analysis of the literature shows there are the unresolved up to now significant contradictions between the theory and the Schwarz experiments. To resolve thes

Joel S. Bader

Current-day genomes bear the mark of the evolutionary processes. One of the strongest indications is the sequence homology among families of proteins that perform similar biological functions in different species. The number of proteins in a family can grow over time as genetic information is duplicated through evolution. We explore how evolution directs the

Daniel R. Phillips, Gautam Rupak, Martin J. Savage

We study a low-energy effective field theory (EFT) describing the NN system in which all exchanged particles are integrated out. We show that fitting the residue of the 3S1 amplitude at the deuteron pole, rather than the 3S1 effective range, dramatically improves the convergence of deuteron observables in this theory. Reproducing the residue ensures that the

Yongkyu Ko

The charge radii and the decay rates of the pion and kaons are calculated, using the relativistic equation of motion with a linear potential. Those physical quantities are quite well explained with the current quark masses in the case of the pion. It is found that the Van Royen-Weisskopf paradox can be cleared out only in the linear potential model by consid

L. Gerland, L. Frankfurt, M. Strikman, H. Stöcker

Last year the E866-group of the Fermilab measured the $x_F$ dependence of $J/Ψ$ and $Ψ&#39;$ suppression in $pA$ collisions. We discuss two of the effects found in that experiment with regard to color coherence effects: the different suppression of the $J/Ψ$ and the $Ψ&#39;$ at $x_F<0$ and the significant suppression of both at large $x_F$. The small $x_F$ r

Agata Olariu, Petre Munteanu-Besliu

In this work we have made an analytical investigation by neutron activation analysis and X-ray fluorescence of a number of pieces found on the two hearths and the slag layer discovered at the Old Town Hall from Sibiu, Romania and some bells from the surrounding region of Sibiu. The elemental analyses suggest the fact that the hearths preserve traces of an ac

R. Kotte, H. W. Barz, C. Plettner, W. Neubert

Small-angle correlations of pairs of nonidentical light charged particles produced in central collisions of heavy ions in the A=100 mass region at a beam energy of 400 AMeV are investigated with the FOPI detector system at GSI Darmstadt. The difference of longitudinal correlation functions with the relative velocity parallel and anti-parallel to the center-o

Alan L Carey, John Phillips, Fyodor Sukochev

We prove that odd unbounded p-summable Fredholm modules are also bounded p-summable Fredholm modules (this is the odd counterpart of a result of A. Connes for the case of even Fredholm modules).

Carolyn S. Gordon, Megan M. Kerr

We construct new homogeneous Einstein spaces with negative Ricci curvature in two ways: First, we give a method for classifying and constructing a class of rank one Einstein solvmanifolds whose derived algebras are two-step nilpotent. As an application, we describe an explicit continuous family of ten-dimensional Einstein manifolds with a two-dimensional par

Kazuyoshi MORI

Anantharam showed in 1985 the existence of a model in which some stabilizable plants do not have its right-/left-coprime factorizations. In this paper, we give a condition of the nonexistence of the right-/left-coprime factorizations of stabilizable plants as a generalization of Anantharam&#39;s result. As examples of the models which satisfy the condition,

S. J. Dilworth, Ralph Howard, James W. Roberts

Let X be a normed space. A subset A of X is approximately convex if $d(ta+(1-t)b,A) \le 1$ for all $a,b \in A$ and $t \in [0,1]$ where $d(x,A)$ is the distance of $x$ to $A$. Let $\Co(A)$ be the convex hull and $\diam(A)$ the diameter of $A$. We prove that every $n$-dimensional normed space contains approximately convex sets $A$ with $\mathcal{H}(A,\Co(A))\g

Alexander David Gottlieb

We establish a necessary and sufficient condition for the propagation of chaos by a family of many-particle Markov processes, if the particles live in a Polish space: a sequence of n-particle Markov transition functions propagates chaos if and only if it propagates chaos for pure initial states.

Nadav Drukker

We derive a new form of loop equations for light-like Wilson loops. In bosonic theories those loop equations close only for straight light-like Wilson lines. In the case of N=1 in ten dimensions they close for any light-like Wilson loop. Upon dimensional reduction to N=4 SYM in four dimensions, these loops become exactly the chiral loops which can be evaluat