November 2001 arXiv papers

A. D. Alhaidari

We derive an elegant analytic formula for the energy spectrum of the relativistic Dirac-Morse problem, which has been solved recently. The new formula displays the properties of the spectrum more vividly.

Jörg Rottler, Sandra Barsky, Mark O. Robbins

We combine molecular dynamics simulations of deformations at the submicron scale with a continuum fracture mechanics calculation for the onset of crack propagation to predict the macroscopic fracture toughness of amorphous glassy polymers. Key ingredients in this multiscale approach are the elastic properties of polymer crazes and the stress at which craze f

A. D. Alhaidari

We obtain exact solutions of Dirac equation at zero kinetic energy for radial power-law relativistic potentials. It turns out that these are the relativistic extension of a subclass of exact solutions of Schrodinger equation with two-term power-law potentials at zero energy. The latter is solved by point canonical transformation of the exactly solvable probl

A. M. Bratkovsky, A. P. Levanyuk

We present the first analytical study of stability loss and evolution of domain structure in inhomogeneous ferroelectric samples for exactly solvable model. The model assumes a short-circuited capacitor with two regions with slightly different critical temperatures Tc1 > Tc2, where Tc1-Tc2 << Tc1, Tc2. Even a tiny inhomogeneity like 10-5 K may result in spli

Max Tegmark, Andrew J. S. Hamilton, Yongzhong Xu

We compute the real-space power spectrum and the redshift-space distortions of galaxies in the 2dF 100k galaxy redshift survey using pseudo-Karhunen-Loeve eigenmodes and the stochastic bias formalism. Our results agree well with those published by the 2dFGRS team, and have the added advantage of producing easy-to-interpret uncorrelated minimum-variance measu

Yeong-Lieh Lin, Franco Nori

We investigate analytically and numerically the mean-field superconducting-normal phase boundaries of two-dimensional superconducting wire networks and Josephson junction arrays immersed in a transverse magnetic field. The geometries we consider include square, honeycomb, triangular, and kagome&#39; lattices. Our approach is based on an analytical study of m

Wayne Hu, Takemi Okamoto

Weak gravitational lensing by the intervening large-scale structure of the Universe induces high-order correlations in the cosmic microwave background (CMB) temperature and polarization fields. We construct minimum variance estimators of the intervening mass distribution out of the six quadratic combinations of the temperature and polarization fields. Polari

M. A. Betemps, M. B. Gay Ducati, M. V. T. Machado

The unitarity corrections effects encoded in the Glauber-Mueller approach are taken into account to calculate the differential cross sections in the Drell-Yan process in the rest frame. A detailed study of the Drell-Yan process in terms of the $γ^{*}q$ transverse separation and the color dipole size, as well as the effective dipole cross section is performed

Andreas Freund, Martin McDermott

We present a detailed next-to-leading order (NLO) leading twist QCD analysis of deeply virtual Compton scattering (DVCS) observables, for several different input scenarios, in the MS-bar scheme. We discuss the size of the NLO effects and the behavior of the observables in skewedness $ζ$, momentum transfer, $t$, and photon virtuality, $q^2=-Q^2$. We present r

G. Koutsoumbas, G. K. Savvidy

We perform Monte Carlo simulations of a three-dimensional spin system with a Hamiltonian which contains only four-spin interaction term. This system describes random surfaces with extrinsic curvature - gonihedric action. We study the anisotropic model when the coupling constants $β_S$ for the space-like plaquettes and $β_T$ for the transverse-like plaquettes

Kyungwha Park, M. A. Novotny, N. S. Dalal, S. Hill

We study theoretically Electron Paramagentic Resonance (EPR) linewidths for single crystals of the molecular magnets Fe$_8$ and Mn$_{12}$ as functions of energy eigenstates $M_s$, frequency, and temperature when a magnetic field along the easy axis is swept at fixed excitation frequency. This work was motivated by recent EPR experiments. To calculate the lin

G. Fritz Benedict, D. Andrew Howell, Inger Jorgensen, Jeffrey D. P. Kenney

Using HST WFPC2 images, we have obtained U, B, V, I, and H-alpha photometry for 76 star clusters in the nuclear star-forming ring of the barred spiral galaxy NGC 4314. These clusters are likely associated with an inner Inner Lindblad Resonance, or IILR. The blue colors and H-alpha emission for most of these clusters imply very young ages of 1-15 Myr. Age est

R. Durrer, B. Novosyadlyj, S. Apunevych

The locations and amplitudes of three acoustic peaks and two dips in the last releases of the Boomerang, MAXIMA and DASI measurements of the cosmic microwave background (CMB) anisotropy power spectra as well as their statistical confidence levels are determined in a model-independent way. It is shown that the Boomerang-2001 data (Netterfield et al. 2001) fix

Soon-Tae Hong

In chiral models with SU(3) group structure, strange form factors of baryon octet are evaluated by constructing their sum rules to yield theoretical predictions comparable to the recent experimental data of SAMPLE Collaboration. We also study sum rules for the flavor singlet axial currents for the EMC experiment in a modified quark model.

Agata Aleksiejuk, Janusz A. Holyst, Gueorgi Kossinets

The question we address here is of whether phenomena of collective bankruptcies are related to self-organized criticality. In order to answer it we propose a simple model of banking networks based on the random directed percolation. We study effects of one bank failure on the nucleation of contagion phase in a financial market. We recognize the power law dis

Stefan Hollands, Robert M. Wald

We establish the existence of local, covariant time ordered products of local Wick polynomials for a free scalar field in curved spacetime. Our time ordered products satisfy all of the hypotheses of our previous uniqueness theorem, so our construction essentially completes the analysis of the existence, uniqueness and renormalizability of the perturbative ex

D. Arnaudon, J. Avan, N. Crampe, L. Frappat

We give a unified RTT presentation of (super)-Yangians Y(g) for so(n), sp(2n) and osp(m|2n).

Syksy Rasanen

We derive the five-dimensional metrics which describe a non-singular boundary brane collision in the ekpyrotic scenario in the context of general relativity, taking into account brane tension. We show that the metrics constrain matter created in the collision to have negative energy density or pressure. In particular, the minimal field content of heterotic M

Susumu Inoue, Dafne Guetta, Franco Pacini

The supranova model of gamma-ray bursts (GRBs), in which the GRB event is preceded by a supernova (SN) explosion by a few months to years, has recently gained support from Fe line detections in X-ray afterglows. A crucial ingredient of this model yet to be studied is the fast-rotating pulsar that should be active during the time interval between the SN and t

Stephan J. Huber, Chin-Aik Lee, Qaisar Shafi

Deviations from standard electroweak physics arise in the framework of a Randall-Sundrum model, with matter and gauge fields in the bulk and the Higgs field localized on the TeV brane. We focus in particular on modifications associated with the weak mixing angle. Comparison with the electroweak precision data yields a rather stringent lower bound of about 10

Roberto Casadio

We analyze the interplay between dispersion relations for the spectrum of Hawking quanta and the statistical mechanics of such a radiation. We first find the general relation between the occupation number density and the energy spectrum of Hawking quanta and then study several cases in details. We show that both the canonical and the microcanonical picture o

J. Damet, G. Ingelman, C. B. Mariotto

Models with essential non-perturbative QCD dynamics for the production of charmonium are extrapolated to give predictions of prompt J/psi production at the LHC. Differences of up to an order of magnitude occurs, although the different models all describe the Tevatron data on high-pT charmonium. An important point is here the treatment of higher order perturb

Xiaoguang Wang

We study the violations of Bell inequality for thermal states of qubits in a multi-qubit Heisenberg model as a function of temperature and external magnetic fields. Unlike the behaviors of the entanglement the violation can not be obtained by increasing the temperature or the magnetic field. The threshold temperatures of the violation are found be less than

Stefano Profumo

Twisted Eguchi-Kawai reduced chiral models are shown to be formally equivalent to a U(1) non-commutative parent theory. The non-commutative theory describes the vacuum dynamics of the non-commutative charged tachyonic field of a brane system. To make contact with the continuum non-commutative theory, a double scaling large N limit for the reduced model is re

Toru Sugitate

Particle correlations and fluctuations measured by RHIC experiments at $\sqrt{s_{NN}}$=130 GeV were discussed. The source size parameters were similar to those measured at the CERN-SPS, and no long duration time of particle emission were observed. It was pointed out that the dependences of longitudinal and transverse radius parameters on the pair momentum ar

J. B. Zhang, S. O. Bilson-Thompson, F. D. R. Bonnet, D. B. Leinweber

We investigate topological charge and the index theorem on finite lattices numerically. Using mean field improved gauge field configurations we calculate the topological charge Q using the gluon field definition with ${\cal O}(a^4)$-improved cooling and an ${\cal O}(a^4)$-improved field strength tensor $F_{\mu\nu}$. We also calculate the index of the massles

Dag Østvang

In this thesis, a non-standard geometric framework, the &#34;quasi-metric&#34; framework (QMF), is used to define relativistic space-time. The QMF consists of a 4-dimensional space-time manifold equipped with two one-parameter families of Lorentzian 4-metrics ${\bf g}_t$ and ${\bf {\bar g}}_t$ parametrized by a (unique) global time function $t$. The global t

Gergely Harcos

We prove an approximate functional equation for the central value of the L-series attached to an irreducible cuspidal automorphic representation of GL(m) over a number field with unitary central character. We investigate the decay rate of the terms involved using the analytic conductor of Iwaniec and Sarnak as a guideline. Straightforward extensions of the r

G. J. Milburn, R. Laflamme, B. C. Sanders, E. Knill

We investigate the difference between classical and quantum dynamics of coupled magnetic dipoles. We prove that in general the dynamics of the classical interaction Hamiltonian differs from the corresponding quantum model, regardless of the initial state. The difference appears as non positive-definite diffusion terms in the quantum evolution equation of an

Lorenza Viola

I revisit the ideas underlying dynamical decoupling methods within the framework of quantum information processing, and examine their potential for direct implementations in terms of encoded rather than physical degrees of freedom. The usefulness of encoded decoupling schemes as a tool for engineering both closed- and open-system encoded evolutions is invest

Evan M. Fortunato, Lorenza Viola, Jonathan Hodges, Grum Teklemariam

We demonstrate storage and manipulation of one qubit encoded into a decoherence-free subspace (DFS) of two nuclear spins using liquid state nuclear magnetic resonance (NMR) techniques. The DFS is spanned by states that are unaffected by arbitrary collective phase noise. Encoding and decoding procedures reversibly map an arbitrary qubit state from a single da

V. V. Belokurov, O. A. Khrustalev, V. A. Sadovnichy, O. D. Timofeevskaya

In this paper we develop the conditional density matrix formalism for adequate description of division and unificationof quantum systems. Applications of this approach to the descriptions of parapositronium, quantum teleportation and others examples are discussed.

N. Debergh, A. A. Pecheritsin, B. F. Samsonov, B. Van den Bossche

A matricial Darboux operator intertwining two one-dimensional stationary Dirac Hamiltonians is constructed. This operator is such that the potential of the second Dirac Hamiltonian as well as the corresponding eigenfunctions are determined through the knowledge of only two eigenfunctions of the first Dirac Hamiltonian. Moreover this operator together with it

Cyriaque Genet, Astrid Lambrecht, Serge Reynaud

When comparing experimental results with theoretical predictions of the Casimir force, the accuracy of the theory is as important as the precision of experiments. Here we evaluate the Casimir force when finite conductivity of the reflectors and finite temperature are simultaneously taken into account. We show that these two corrections are correlated, i.e. t

S. Rebić, A. S. Parkins, S. M. Tan

We present a complete analytical solution for a single four-level atom strongly coupled to a cavity field mode and driven by external coherent laser fields. The four-level atomic system consists of a three-level subsystem in an EIT configuration, plus an additional atomic level; this system has been predicted to exhibit a photon blockade effect. The solution

Nguyen Ba An, Truong Minh Duc

A scheme of generating recently introduced fan-states | α, 2k>_F (αis complex, k=1,2,3,...) is proposed basing on a Λ-type atom-cavity field interaction. We show that with suitable atomic preparations and measurements a passage of a sequence of N atoms through a cavity may transform an initial field coherent state | α> to a fan-state | α, 2k>_F with k=2^{N-2

Akhlesh Lakhtakia

An electromagnetic trinity comprising vacuum, anti--vacuum, and nihility is postulated -- after making use of materials with &#34;negative permittivity&#34; and &#34;negative permeability&#34; -- to illuminate the structure of electromagnetic theory, at least insofar as the relationship of phase velocity with Poynting vector is concerned.

F. Benamira, L. Guechi

By using similarity transformations approach, the exact propagator for a generalized one-dimensional Fokker-Planck equation, with linear drift force and space-time dependent diffusion coefficient, is obtained. The method is simple and enables us to recover and generalize special cases studied through the Lie algebraic approach and the Green function techniqu

Aleksey E. Bolotnikov, C. M. Hubert Chen, Walter R. Cook, Fiona A. Harrison

We studied the effects of bulk and surface conductivity on the performance of high-resistivity CdZnTe (CZT) pixel detectors with Pt contacts. We emphasize the difference in mechanisms of the bulk and surface conductivity as indicated by their different temperature behaviors. In addition, the existence of a thin (10-100 A) oxide layer on the surface of CZT, f

V. F. Gubarev, L. M. Yakovleva, N. N. Aksenov, A. V. Palagin

Recently, interest has grown for application of reconfigurable devices in robust and adaptive control systems. The main advantage of such devices is that its structure is not fixed and may be varied depending on the currently used control algorithm. In this paper a new PC-based reconfigurable microcontrollers (RMC) are offered for Experimental Physics contro

M. Mudrich, S. Kraft, K. Singer, R. Grimm

We simultaneously trap ultracold lithium and cesium atoms in an optical dipole trap formed by the focus of a CO$_2$ laser and study the exchange of thermal energy between the gases. The cesium gas, which is optically cooled to $20 μ$K, efficiently decreases the temperature of the lithium gas through sympathetic cooling. The measured cross section for thermal

Vladimir S. Semenov, Daniil B. Korovinski, Helfried K. Biernat

In the MHD description of plasma phenomena the concept of magnetic helicity turns out to be very useful. We present here an example of introducing Euler potentials into a topological MHD soliton which has non-trivial helicity. The MHD soliton solution (Kamchatnov, 1982) is based on the Hopf invariant of the mapping of a 3D sphere into a 2D sphere; it can hav

S. I. Vainshtein

In experimental study of very high Reynolds number turbulence, we found evidences that there are distinguished vortex structures in the intermediate range, that is, between the Kolmogorov and Taylor microscales, where they are indeed expected to be present. These structures are responsible for the intermittency, and, in the same time, they contribute into as

M. Clausen, Ron MacKenzie, Robert Sass, Hamid Shoaee

The current SLC control system was designed and constructed over 20 years ago. Many of the technologies on which it was based are obsolete and difficult to maintain. The VMS system that forms the core of the Control System is still robust but third party applications are almost non-existent and its long-term future is in doubt. The need for a Control System

A. Sibirtsev, S. Schneider, Ch. Elster, J. Haidenbauer

An analysis of incoherent photoproduction of $η$ mesons off the deuteron for photon energies from threshold to 800 MeV is presented. The dominant contribution, the $γ$N-$η$N amplitude, is described within an isobar model. Effects of the final state interactions in the $NN$ as well as the $ηN$ systems are included employing models derived within the meson-exc

M. J. van Goethem, L. Aphecetche, J. C. S. Bacelar, H. Delagrange

Photon energy spectra up to the kinematic limit have been measured in 190 MeV proton reactions with light and heavy nuclei to investigate the influence of the multiple-scattering process on the photon production. Relative to the predictions of models based on a quasi-free production mechanism a strong suppression of bremsstrahlung is observed in the low-ener

G. A. Sokol, L. N. Pavlyuchenko

First experimental results from a photoreaction which confirm an existence of eta-mesic nuclei are discussed. The experiment was performed at the 1 GeV electron synchrotron of LPI. Two values of the end-point energy of the bremsstrahlung beam were used, 650 and 850 MeV (below and above eta-photoproduction threshold on the nucleon). Correlated pi+ n pairs fly

Avinash Khare, Uday Sukhatme

Even though the KdV and modified KdV equations are nonlinear, we show that suitable linear combinations of known periodic solutions involving Jacobi elliptic functions yield a large class of additional solutions. This procedure works by virtue of some remarkable new identities satisfied by the elliptic functions.

Sumio Yamada

Harmonic mappings into Teichmuller spaces appear in the study of manifolds which are fibrations whose fibers are Riemann surfaces. In this article we will study the existence and uniquenesses questions of harmonic mappings into Teichmuller spaces, as well as some local and global behavior of the harmonic images induced by the Weil-Petersson geometry of Teich

Alex Brudnyi

We improve an estimate (obtained in &#34;A.Brudnyi, Small amplitude limit cycles and the distribution of zeros of families of analytic functions, Ann. of Math. 154 (2) (2001), 227-243&#34;) for the average number of limit cycles of a planar polynomial vector field situated in a neighbourhood of the origin provided that the field in a larger neighbourhood is

Sumio Yamada

Given a surface of higher genus, we will look at the Weil-Petersson completion of the Teichmuller space of the surface, and will study the isometric action of the mapping class group on it. The main observation is that the geometric characteristics of the setting bear strong similarities to the ones in semi-simple Lie group actions on noncompact symmetric sp

Allan M. Sinclair, Roger R. Smith

We investigate maximal abelian subalgebras (masas) in separably acting type $II_1$ factors. We use the notion of distance between masas which we introduced in an earlier paper in this archive, OA/0107075. The main result of the paper is to show that for any unitary u and a masa A, the distance between A and uAu* is comparable to the distance in 2-norm from u

Christian Krattenthaler

We prove several evaluations of determinants of matrices, the entries of which are given by the recurrence $a_{i,j}=a_{i-1,j}+a_{i,j-1}$, or variations thereof. These evaluations were either conjectured or extend conjectures by Roland Bacher [J. Théorie Nombres Bordeaux 13 (2001), to appear; see http://arxiv.org/abs/math.CO/0109013].

Michel Boileau, Richard Weidmann

We prove a structure theorem for 3-manifolds with non-trivial JSJ-decomposition and 2-generated fundamental group. We deduce a variety of Corollaries. Note this is not a complete classification of such manifolds. In particular we believe that one of the families in our list is empty. If you know something about hyperbolic 2-bridge knot exteriors and their fi

Jianyuan K. Zhong, Bin Lu

Following the recent work by Chan, and by Morton and Hadji on the Homflypt polynomials of some generalized Hopf links, we investigate the Kauffman polynomials of generalized Hopf links. By studying the Kauffman skein module of the solid torus S^1\times D^2, we establish a similar skein map on the Kauffman skein module of S^1\times D^2 which has distinct eige

Carlos A. Torre

Three definitions of a differential form on a tangent structure are considere. It is proved that the (covariant) definition given by Souriau (as a collection of forms indexed by the plaques) is equivalent to a smooth section of the corresponding vector bundle if the space does not have transverse points.

Stefano Bianchini, Alberto Bressan

We consider the Cauchy problem for a strictly hyperbolic, $n\times n$ system in one space dimension: $u_t+A(u)u_x=0$, assuming that the initial data has small total variation. We show that the solutions of the viscous approximations $u_t+A(u)u_x=\ve u_{xx}$ are defined globally in time and satisfy uniform BV estimates, independent of $\ve$. Moreover, they de

P. Desmedt, J. Quaegebeur, S. Vaes

We study stability properties of amenable locally compact quantum groups under the bicrossed product construction. We obtain as our main result an equivalence between amenability of the bicrossed product and amenability of the matched quantum groups used as building ingredients of the bicrossed product. Finally, we give examples of non-amenable locally compa

Emilia Mezzetti, Orsola Tommasi

We study families of linear spaces in projective space whose union is a proper subvariety X of the expected dimension. We establish relations between configurations of focal points and existence or non-existence of a fixed tangent space to X along a general element of the family. We apply our results to the classification of ruled 3-dimensional varieties.

Andrew Ranicki

An introduction to circle valued Morse theory and Novikov homology, from an algebraic point of view.

Andrew Ranicki

An introduction to the applications of algebraic surgery to the structure theory of high-dimensional topological manifolds.

Andrew Ranicki

An elementary introduction to the principles of algebraic surgery.

Yukari Ito

There are many generalizations of the McKay correspondence for higher dimensional Gorenstein quotient singularities and there are some applications to compute the topological invariants today. But some of the invariants are completely different from the classical invariants, in particular for non-Gorenstein cases. In this paper, we would like to discuss the

Nobuhiro Asai

Let $μ_p^{(q)}$ be the q-deformed Poisson measure in the sense of Saitoh Yoshida and $ν_p$ be the measure given by Equation \eqref{eq:nu-q}. In this short paper, we introduce the q-deformed analogue of the Segal-Bargmann transform associated with $μ_p^{(q)}$. We prove that our Segal-Bargmann transform is a unitary map of $L^2(μ_p^{(q)})$ onto the q-deformed

Paul H. Frampton, Sheldon L. Glashow, Thomas W. Kephart, Ryan M. Rohm

Finite groups are of the greatest importance in science. Loops are a simple generalization of finite groups: they share all the group axioms except for the requirement that the binary operation be associative. The least loops that are not themselves groups are those of order five. We offer a brief discussion of these loops and challenge the reader (especiall

M. Bouhmadi-Lopez, P. F. Gonzalez-Diaz, A. Zhuk

By considering 5--dimensional cosmological models with a bulk filled with a perfect fluid and a cosmological constant, we have found regular instantonic solution which is free from any singularity at the origin of the extra--coordinate and describe 5--dimensional asymptotically anti de Sitter wormhole, when the bulk has a topology $ R \times S^4 $ and is fil

Gleb Arutyunov, Jan Plefka, Matthias Staudacher

We further analyze a recent perturbative two-loop calculation of the expectation value of two axi-symmetric circular Maldacena-Wilson loops in N=4 gauge theory. Firstly, it is demonstrated how to adapt the previous calculation of anti-symmetrically oriented circles to the symmetric case. By shrinking one of the circles to zero size we then explicitly work ou

Davide Fioravanti

As a prototype of powerful non-abelian symmetry in an Integrable System, I will show the appearance of a Witt algebra of vector fields in the SG theory. This symmetry does not share anything with the well-known Virasoro algebra of the conformal $c=1$ unperturbed limit. Although it is quasi-local in the SG field theory, nevertheless it gives rise to a local a

S. Groot Nibbelink

The ultra-violet behavior of Kaluza-Klein theories on a one dimensional orbifold is discussed. An extension of dimensional regularization that can be applied to a compact dimension is presented. Using this, the FI-tadpole is calculated in the effective KK theory resulting from compactifying supersymmetric theories in 5 dimensions.

Grigorii B. Pivovarov, James P. Vary

We consider SU(2) gauge potentials over a space with a compactified dimension. A non-Abelian Fourier transform of the gauge potential in the compactified dimension is defined in such a way that the Fourier coefficients are (almost) gauge invariant. The functional measure and the gauge field strengths are expressed in terms of these Fourier coefficients. The

G. D&#39;Appollonio

Unabridged version of the Thesis presented to the University of L&#39; Aquila, in partial fulfillment of the requirements for the ``Laurea&#39;&#39; degree in Physics, October 1998. Work carried out at the University of L&#39;Aquila and at the University of Rome ``Tor Vergata&#39;&#39;.

Kazunari Shima

The fundamental action of superon-graviton model(SGM) for space-time and matter is written down explicitly in terms of the fields of the graviton and superons by using the affine and the spin connection formalisms, alternatively. Some characteristic structures including some hidden symmetries of the gravitational coupling of superons are manifested (in two d

R. P. Woodard

I present an exact solution for the Heisenberg picture, Dirac electron in the presence of an electric field which depends arbitrarily upon the light cone time parameter $x^+ = (t+x)/\sqrt{2}$. This is the largest class of background fields for which the mode functions have ever been obtained. The solution applies to electrons of any mass and in any spacetime

Jiri Chyla

Current theoretical framework for the calculation of heavy quark production in $γγ$ collisions is reviewed. The importance of including direct photon contributions up to the order $α^2α_s^2$ and of the proper choice of renormalization and factorization scales in the evaluation of $σ(γγ\to Q\bar{Q})$ is emphasized.

M. Strikman, D. Treleani

We predict a strong enhancement of multijet production in proton-nucleus collisions at collider energies, as compared to a naive expectation of a cross section $\propto A$. The study of the process would allow to measure, for the first time, the double parton distribution functions in a nucleon in a model independent way and hence to study both the longitudi

Johann Rafelski, Jean Letessier

Analysis of hadron production experimental data allows to understand the properties of the dense matter fireball produced in relativistic heavy ion collisions. We interpret the analysis results and argue that color deconfined state has been formed at highest CERN-SPS energies and at BNL-RHIC.

Aseshkrishna Datta, Abdelhak Djouadi

In the context of the Minimal Supersymmetric extension of the Standard Model, we analyze the production at future high-energy $e^+e^-$ colliders of second and third generation scalar leptons as well as scalar quarks in association with neutralinos and charginos, $e^+e^-\to f\tilde{f}χ$. In the case of third generation squarks, we also discuss the associated

Katri Huitu

Single production at hadron and photon colliders of gluinos and sneutrinos of supersymmetric models, as well as radions of the Randall-Sundrum model, is discussed. In the case of supersymmetry, R-parity breaking is needed in order to produce single susy particles. Resonant production of radions is considered at gamma-gamma collider.

Wolfram Kittel

Far too often are multiparticle final states studied and models tested on merely single-particle spectra and their integrals, the average multiplicities: A multiparticle final state is a non-linear, complex system and the essential information on the dynamics is contained in the particle correlations and their integrals measuring the fluctuations!

O. V. Utyuzh, G. Wilk, Z. Wlodarczyk

We demonstrate algorithm for numerical modelling of Bose-Einstein correlations (BEC) formulated on quantum statistical level for a single event and exploring the property that identical particles subjected to Bose statistics do bunch themselves in a maximal possible way in the same cells in phase-space.

Wolfgang Ochs

We review the predictions on angular correlations and their recent experimental tests at LEP and HERA. Power behaviour of correlation functions appear for large angles and reflect the underlying fractal structure in jet evolution. Asymptotic scaling laws work rather well for the low momentum particles. For angular correlations the predictions work at least q

M. Adamus, S. Chekanov, K. Olkiewicz, L. Zawiejski

Results of the recent studies of the multiplicity fluctuations and Bose-Einstein correlations (BEC) in deep-inelastic scattering (DIS) at large Q$^2$ are reviewed. The measurements were done with the ZEUS detetor at HERA.

Bai YuTing, Fu JingHua, Wu YuanFang

We present a study of event-by-event fluctuations of transverse momentum in $π^{+}\p$ and $\K^{+}\p$ collisions at 250 GeV/$c$ and the corresponding PYTHIA Monte Carlo results for $π^{+}\p$ collisions. The dependence of $Φ_{p_{t}}$ on event and particle variables are investigated in detail. We find that $Φ_{p_t}$ are all negative for different average transv

A. A. Savin

Diffractive processes in photon-proton interactions at HERA offer the opportunity to improve the understanding of the transition between the soft, non-perturbative regime in hadronic interactions at $Q^2 = 0$ and the perturbative region at high $Q^2$. Recent experimental results from HERA on inclusive diffractive scattering, exclusive vector meson production

N. N. Nikolaev

A brief review of the modern QCD theory of diffractive DIS is given.

S. Munier

Through a determination of the $S$-matrix element for the scattering of a localized colour dipole on a proton, we show that saturation effects can already be sizable at HERA. The saturation scale is found to be around 1-1.5 $GeV^2$ for the highest available energies and for central collisions, and is a decreasing function of the impact parameter.

Uri Maor

I examines the applicability and possible need for a re-formulation of pQCD, as we know it, in the DIS limit of small $Q^2$ and $x$. Gluon saturation, implied by s-channel unitarity, and its possible experimental signatures are critically assessed.

A. MaŁecki, D. Goc-JagŁo

The rôle of inelastic diffraction in elastic scattering of nuclei is studied in the formalism of \emph{diffractive limit}. The results obtained for scattering of the $α$--particles on light nuclei show that the nucleonic diffraction is especially important at large momentum transfers where the Glauber model of geometric diffraction fails.

Gösta Gustafson

A simple model for the gluon structure function at small $x$ is presented, which gives an intuitive picture of the transition between the DGLAP and B FKL regimes.

J. A. van Dalen

Analyses of Bose-Einstein Correlations in $\rW^{+}\rW^{-}$ events at LEP2 by the four LEP collaborations are presented. In particular, Bose-Einstein correlations in $\rW^{+}\rW^{-}$ overlap are investigated and the possible existence of these correlations between particles coming from different W&#39;s, which may influence the W-mass measurements in the full

Errol Gotsman

We examine HERA data with a view of determining whether unique signs of saturation can be identified. Concentrating on two channels the logarithmic slope of $F_{2}$, and the production of $J/Ψ$, which are sensitive to the behaviour of $xG(x,Q^{2})$ the gluon density distribution in the proton, we show that our model incorporating screening corrections and al

Cong-Feng Qiao

The status of Charmonium production in photon-photon collisions is briefly reviewed. I would like to mention that although the preliminary data were obtained in experiment, the theoretical investigation is not in a compatible status.

R. N. Lee, A. L. Maslennikov, A. I. Milstein, V. M. Strakhovenko

Photon splitting due to vacuum polarization in the electric field of an atom is considered. We survey different theoretical approaches to the description of this nonlinear QED process and several attempts of its experimental observation. We present the results of the lowest-order perturbation theory as well as those obtained within the quasiclassical approxi

M. E. Carrington, Hou Defu, R. Kobes

We perform a Chapman-Enskog expansion of the Boltzmann equation keeping up to quadratic contributions. We obtain a generalized nonlinear Kubo formula, and a set of integral equations which resum ladder and extended ladder diagrams. We show that these two equations have exactly the same structure, and thus provide a diagrammatic interpretation of the Chapman-

L. I. Gurvits

Interferometry is one of the most powerful experimental tools of modern astrophysics. Some of its methods are considered in view of potential applicability to studies of correlations in multiparticle dynamics.

M. B. Gay Ducati, V. P. Gonçalves, M. V. T. Machado

The logarithmic slope of the diffractive structure function is a potential observable scanning the hard and soft contributions in diffraction, allowing to disentangle the QCD dynamics. We report our calculations concerning this quantity, in particular the estimates emerging from the saturation model applied to diffraction dissociation.

L. Demortier

We review the diffractive measurements made by the CDF and DØ collaborations during Run I at the Tevatron and summarize the detector upgrades relevant for the Run II diffractive physics program.

Philippe Jetzer

The nature of the dark matter in the halo of our Galaxy is still largely unknown. The microlensing events found so far towards the Large Magellanic Cloud suggest that at most about 20% of the halo dark matter is in the form of MACHOs (Massive Astrophysical Compact Halo Objects). The dark matter could also, at least partially, consist of cold molecular clouds

Jean-Noël Capdevielle, Fabrice Cohen, Corentin Le Gall

We describe the general aspects of Monte Carlo Collision Generators suitable for cosmic ray nucleon-Air and nuclei-Air interactions, including accelerator and collider data. The problem of the extrapolation at 3 energy decades above the LHC of the main features of high energy collisions is discussed and under theoretical and phenomenological assumptions, the

Peter A. Steinberg

The multiplicity of charged particles produced in Au+Au collisions as a function of energy, centrality, rapidity and azimuthal angle has been measured with the PHOBOS detector at RHIC. These results contribute to our understanding of the initial state of heavy ion collisions and provide a means to compare basic features of particle production in nuclear coll