August 1996 arXiv papers — page 12

Marcelo M. Leite, Victor O. Rivelles

We show that two-dimensional topological BF theories coupled to particles carrying non-Abelian charge admit a new coupling involving the Lagrange multiplier field. When applied to the gauge theoretic formulation of dilatonic gravity it gives rise to a source term for the gravitational field. We show that the system admits black hole solutions.

Andrew M. Steane

An introductory review of the linear ion trap is given, with particular regard to its use for quantum information processing. The discussion aims to bring together ideas from information theory and experimental ion trapping, to provide a resource to workers unfamiliar with one or the other of these subjects. It is shown that information theory provides valua

A. De Pace, C. Garcia-Recio, E. Oset

Quasielastic K^+ - nucleus scattering data at q=290, 390 and 480 MeV/c are analyzed in a finite nucleus continuum random phase approximation framework, using a density-dependent particle-hole interaction. The reaction mechanism is consistently treated according to Glauber theory, keeping up to two-step inelastic processes. A good description of the data is a

D. P. Kirilova, M. V. Chizhov

We studied nonequilibrium oscillations between left-handed electron neutrinos and nonthermalized sterile neutrinos in medium for resonant and nonresonant cases. The exact kinetic equations for neutrinos, written in terms of neutrino density matrix in {\it momentum space} were analyzed. The evolution of neutrino density matrix was numerically calculated. This

E. H. Simmons

A flavor-universal extension of the strong interactions was recently proposed in response to the apparent excess of high-$E_T$ jets in the inclusive jet spectrum measured at the Tevatron. This paper studies the color octet of massive gauge bosons (`colorons') that is present in the low-energy spectrum of the model's Higgs phase. Constraints from sear

John D. Barrow, Kerstin E. Kunze

We determine the most general form of the antisymmetric $H$-field tensor derived from a purely time-dependent potential that is admitted by all possible spatially homogeneous cosmological models in 3+1-dimensional low-energy bosonic string theory. The maximum number of components of the $H$ field that are left arbitrary is found for each homogeneous cosmolog

B. L. Ioffe

The theorem is proved, determining the forward scatterring amplitude of virtual longitudinal photon at zero energy on any hadronic target in the limit of small photon virtualities $Q^2$. The theorem is strict, based only on Lorenz and gauge invariance. No assumptions about the strong interaction, besides the gap in the mass spectrum, are used. Two terms in t

C. Alcock, R. A. Allsman, D. Alves, T. S. Axelrod

We report the discovery of 73 double-mode RR Lyrae (RRd) stars in fields near the bar of the LMC. The stars are detected among the MACHO database of short-period variables that currently contains about 7900 RR Lyrae stars. Fundamental periods (P_0) for these stars are found in the range 0.46-0.55 days and first overtone-to-fundamental period ratios are found

J. -M. Frère, R. B. Nevzorov, M. I. Vysotsky

Recent experiment proposed to observe induced radiative neutrino transitions are confronted to existing bounds on neutrino magnetic moments from earth-based experiments. These are found to exclude any observation by several orders of magnitude, unless the magnetic moments are assumed to be strongly momentum dependent. This possibility is discussed in some ge

M. Biskup, P. Cejnar, R. Kotecky

Certain physical aspects of quantum error correction are discussed for a quantum computer (n-qubit register) in contact with a decohering environment. Under rather plausible assumptions upon the form of the computer-environment interaction, the efficiency of a general correcting procedure is evaluated as a function of the spontaneous-decay duration and the r

J. Hwang

We calculate the density and gravitational wave spectrums generated in a version of string cosmology termed pre-big bang scenario. The large scale structures are originated from quantum fluctuations of the metric and dilaton field during a pole-like inflation stage driven by a potential-less dilaton field realized in the low-energy effective action of string

Xiao-Gang He, A. Soni

We study $c \bar c$ color-octet contribution to $B\to ψ(ψ') X$. When this contribution is included, the theoretical predictions for the branching ratios become in much better agreement with the experiment. This mechanism also enhances the partial rate asymmetries by about a factor of five. The inclusive $ψ(ψ')$ resulting from $b\to d+{}$gluon can hav

Jorge Berger, Jacob Rubinstein

This is an analytic study of the problem of transitions between normal and superconducting phases for a sample which encloses a magnetic flux. A preliminary study of this problem, based on numerical minimization of the free energy for a particular form of the thickness of the sample, was published in Phys. Rev. Lett. {\bf 75}, 320 (1995). For a sample of uni

Emanuel Knill, Raymond Laflamme

One of the main problems for the future of practical quantum computing is to stabilize the computation against unwanted interactions with the environment and imperfections in the applied operations. Existing proposals for quantum memories and quantum channels require gates with asymptotically zero error to store or transmit an input quantum state for arbitra

Thomas Schaefer

I review the current understanding of the chiral phase transition in QCD, with particular emphasis on recent results obtained in the instanton liquid model.

Y. Pang, D. E. Kahana, S. H. Kahana, H. Crawford

Antinucleon production in heavy ion collisions is potentially an excellent signal for unusual phenomena in hot and dense matter. However, at the low energies available at the AGS the annihilation process must be handled with care. In this Comment, we consider the case of Au + Au collisions at approximately 11 GeV/c, applying the ARC treatment of pbar product

Kari J. Eskola, Berndt Müller, Xin-Nian Wang

The high density of scattered partons predicted in nuclear collisions at very high energy makes color screening effects significant. We explain how these screening mechanisms may suppress nonperturbative, soft QCD processes, permitting a consistent calculation of quark-gluon plasma formation within the framework of perturbative QCD. We present results of a m

Pavlos Protopapas, Abraham Klein

We review briefly the fundamental equations of a semi-microscopic core-particle coupling method that makes no reference to an intrinsic system of coordinates. We then demonstrate how an intrinsic system can be introduced in the strong coupling limit so as to yield a completely equivalent formulation. It is emphasized that the conventional core-particle coupl

R. Nouicer, C. Beck, D. Mahboub, T. Matsuse

The properties of the two-body channels in the $^{35}$Cl + $^{24}$Mg reaction at a bombarding energy of 275 MeV have been investigated by using fragment-fragment coincident techniques. The exclusive data show that the majority of events arises from a binary-decay process. The rather large number of secondary light charged-particles emitted from the two excit

Vladimir Kanovei, Michael Reeken

A new elementary nonstandard proof of the Jordan curve theorem is given. The proof (the technical part consists of 4 pages) is self-contained, except for the Jordan theorem for polygons taken for granted.

Hidenori Sonoda

By completing the old discussion of K.~Wilson, we express the chiral anomaly in terms of a double integral of a three-point function of chiral currents over an arbitrarily small region in the coordinate space. An integrability condition provides an important finite local counterterm to the integral.

Carl M. Bender, Kimball A. Milton

A new version of the delta expansion is presented, which, unlike the conventional delta expansion, can be used to do nonperturbative calculations in a self-interacting scalar quantum field theory having broken symmetry. We calculate the expectation value of the scalar field to first order in delta, where delta is a measure of the degree of nonlinearity in th

Joseph A. Minahan, Dennis Nemeschansky

We obtain the elliptic curve corresponding to an $N=2$ superconformal field theory which has an $E_6$ global symmetry at the strong coupling point $τ=e^{πi/3}$. We also find the Seiberg-Witten differential $λ_{SW}$ for this theory. This differential has 27 poles corresponding to the fundamental representation of $E_6$. The complex conjugate representation ha

Kenneth Intriligator, Scott Thomas

Dynamical supersymmetry breaking is considered in models which admit descriptions in terms of electric, confined, or magnetic degrees of freedom in various limits. In this way, a variety of seemingly different theories which break supersymmetry are actually inter-related by confinement or duality. Specific examples are given in which there are two dual descr

Tomas Ortin

We review some recent work on the existence and classification of extreme black-hole-type solutions in N=8 supergravity. For the black holes considered (those that are also solutions of N=4 supergravity and of the Einstein-Maxwell-dilaton theory with coupling a) a complete classification is achieved: the only possible values of a are \sqrt{3},1,1/\sqrt{3},0.

T. Heinzl

We discuss the definition of condensates within light-cone quantum field theory. As the vacuum state in this formulation is trivial, we suggest to abstract vacuum properties from the particle spectrum. The latter can in principle be calculated by solving the eigenvalue problem of the light-cone Hamiltonian. We focus on fermionic condensates which are order p

Heinrich Saller

The numerical input for the quantitative consequences of the electroweak standard model, the hypercharge and isospin coupling constants and the Higgs field ground state mass value, are interpreted as normalizations of the symmetries involved. Using an additional statistical argument, a first order quantitative determination of the Weinberg angle as a normali

T. Fujiwara, H. Igarashi, Y. Takimoto

Exact operator solution for quantum Liouville theory is investigated based on the canonical free field. Locality, the field equation and the canonical commutation relations are examined based on the exchange algebra hidden in the theory. The exact solution proposed by Otto and Weigt is shown to be correct to all order in the cosmological constant.

J. Lopez, D. Nanopoulos

We explore two possible interpretations for the CDF $eeγγ+E_T\hskip-13pt/\quad$ event in the context of a recently proposed one-parameter no-scale supergravity model with a light gravitino. We delineate the region in parameter space consistent with the kinematics of the event interpreted either as selectron pair-production ($p\bar p\to\tilde e^+\tilde e^-\,X

Thomas G. Rizzo

We investigate the capability of the NLC to indirectly determine both the mass as well as the couplings to leptons and $b$-quarks of a new neutral gauge boson below direct production threshold. By using data collected at several different values of the collider center of mass energy, we demonstrate how this can be done in an anonymous and model-independent m

Tomas Blazek, Marcela Carena, Stuart Raby, Carlos Wagner

We present a global $χ^2$ analysis of electroweak data, including fermion masses and mixing angles, in SO(10) SUSY GUTs. Just as precision electroweak data is used to test the Standard Model, the well determined Standard Model parameters are the precision electroweak data for testing theories beyond the Standard Model. In this talk we use the latest experime

N. Tetradis

We study the high-temperature phase transitions for the Abelian and $SU(2)$ Higgs models, using the exact renormalization group. The evolution equation for a properly-defined coarse-grained free energy is solved. The phase diagram of the Abelian Higgs model has a region of second-order phase transitions governed by fixed points, for which we calculate critic

Per Elmfors

The fermionic dispersion relation in the presence of a background magnetic field and a high temperature QED plasma is calculated exactly in the external field, using the Hard Thermal Loop effective action. As the field strength increases there is a smooth transition from the weak-field ($qB\ll q^2T^2$) thermal dispersion relations to the vacuum Landau levels

Mitsuru Ishii

In a homogeneous pionic gas system, chemical nonequilibrium process is considered to understand its effect in the expansion processes that are realized immediately after heavy ion collisions. The chemical relaxation time is calculated by incorporating the $π+π\leftrightarrow π+π+π+π$ reaction, which is given in the second order of perturbation in the $σ$ mod

Debajyoti Choudhury, D. P. Roy

We discuss an optimal $R$-parity breaking SUSY solution to the $R_b$ excess as well as the ALEPH 4-jet anomaly. The latter arises from the pair production of stop via chargino decay at LEP1.5, followed by its $R$--violating decay into a light quark pair. The model satisfies top quark and $Z$--boson decay constraints along with gaugino mass unification.

Michiyasu Nagasawa, Jun'ichi Yokoyama

We formulate a local condition for a nontopological defect to be present. We apply it for electroweak strings and estimate the probability of their existence at the Ginzburg temperature. As a result we find strings long enough to serve for baryon-number generation are unlikely to be produced.

Kimball A. Milton

An alternative approach to lattice gauge theory has been under development for the past decade. It is based on discretizing the operator Heisenberg equations of motion in such a way as to preserve the canonical commutation relations at each lattice site. It is now known how to formulate a non-Abelian gauge theory within this framework. The formulation appear

M. J. Bowick, S. Catterall, M. Falcioni, G. Thorleifsson

The statistical mechanics of flexible two-dimensional surfaces (membranes) appears in a wide variety of physical settings. In this talk we discuss the simplest case of fixed-connectivity surfaces. We first review the current theoretical understanding of the remarkable flat phase of such membranes. We then summarize the results of a recent large scale Monte C

T. Neuhaus

Employing a variant of the Multicanonical Ensemble we study twisted spin configurations on periodic boxes in the $D=2$ $O(3)$ nonlinear sigma model for $β$-values inbetween $1.55$ to $3.1$. The free energy difference of twisted spin configurations is determined from the constraint effective potential. The finite size scaling behavior is in accordance with th

S. Catterall, G. Thorleifsson, R. Renken, J. Kogut

We consider two issues in the DT model of quantum gravity. First, it is shown that the triangulation space for D>3 is dominated by triangulations containing a single singular (D-3)-simplex composed of vertices with divergent dual volumes. Second we study the ergodicity of current simulation algorithms. Results from runs conducted close to the phase transitio

A. J. van der Sijs

A new partial gauge fixing condition for the abelian projection is introduced. It is based on the lowest-lying eigenvector of a covariant Laplacian operator. This gauge is smooth and free of lattice Gribov copies. These properties are important for an unambiguous computation of the abelian projected gauge field configuration.

SESAM-Collaboration, :, N. Eicker, U. Glässner

In a full QCD lattice study with $N_f = 2$ Wilson fermions, we seek to optimize the signals for the disconnected contributions to the matrix element of flavour-singlet operators between nucleon states, which are indicative for sea quark effects. We demonstrate, in form of a fluctuation analysis to the noisy estimator technique, that -- in order to achieve a

V. Gimenez, G. Martinelli, C. T. Sachrajda

We present a short review of our most recent high statistics lattice determinations in the HQET of the following important parameters in B physics: the B--meson binding energy, $\overlineΛ$ and the kinetic energy of the b quark in the B meson, $λ_1$, which due to the presence of power divergences require a non--perturbative renormalization to be defined; the

M. Feurstein, H. Markum, St. Thurner

We analyze topological objects in pure gluonic $SU(2)$ lattice gauge theory and compute correlation functions between instantons and monopoles. Concerning the instantons we use geometric and field theoretic definitions of the topological charge. On a $12^3\times 4$ lattice it turns out that topological quantities have a non-trivial local correlation. The aut

M. Feurstein, H. Markum, St. Thurner

Recently evidence appeared that instantons and monopoles have a certain local correlation in four-dimensional pure $SU(2)$ and $SU(3)$ gauge theory. We visualize several specific gauge field configurations and show directly that there is an enhanced probability for finding maximally projected abelian monopole loops in the vicinity of instantons. This feature

Margarita Garcia Perez, Jeroen Snippe, Pierre van Baal

Scaling of mass ratios in intermediate volumes, obtained with improved SU(2) lattice actions is tested against analytic results for the Wilson and continuum action. A new improved action is introduced by adding a 2X2 plaquette to the Symanzik action. Completing a square leads to a covariant propagator that simplifies perturbative calculations. Data is presen

A. Gonzalez-Arroyo, A. Montero

We construct a family of smooth, almost self-dual, non-thermalized SU(2) gauge field configurations, and measure the average of the fundamental, adjoint and spin $\frac{3}{2}$ representation Wilson loops on them. We get area law in all three cases. We also study thermalised configurations at $β= 2.325$ after cooling. The ratio of string tension in the spin j

UKQCD Collaboration, presented by Richard Kenway

We compare results obtained using the Sheikholeslami-Wohlert (SW) fermion action with tree-level and tadpole-improved coefficients for $5.7\leβ\le 6.2$.

M. Goeckeler, R. Horsley, E. -M. Ilgenfritz, H. Oelrich

The renormalisation constants for local bilinear quark operators are calculated using the Sheikholeslami-Wohlert improved action. In addition we compute the renormalisation constant of the leading gluon operator for different group representations and discuss the mixing of the operators E^2 and B^2.

D. V. Gal'tsov

We consider dilaton--axion gravity interacting with $p\;\, U(1)$ vectors ($p=6$ corresponding to $N=4$ supergravity) in four--dimensional spacetime admitting a non--null Killing vector field. It is argued that this theory exibits features of a ``square'' of vacuum General Relativity. In the three--dimensional formulation it is equivalent to a gravity

M. Rainer, A. Zhuk

Inhomogeneous multidimensional cosmological models with a higher dimensional space-time manifold M=M_0 x M_1 x ... M_n are investigated under dimensional reduction to tensor-multi-scalar theories. In the Einstein conformal frame, these theories take the shape of a flat sigma-model. For the singular case where M_0 is 2-dimensional, the dimensional reduction t

Bozhidar Z. Iliev

A treatment in a neighborhood and at a point of the equivalence principle on the basis of derivations of the tensor algebra over a manifold is given. Necessary and sufficient conditions are given for the existence of local bases, called normal frames, in which the components of derivations vanish in a neighborhood or at a point. These frames (bases), if any,

J. Hwang

In this brief note we present a set of equations describing the evolution of perturbed scalar fields in a cosmological spacetime with multiple scalar fields. We take into account of the simultaneously excited full metric perturbations in the context of the uniform-curvature gauge which is known to be the best choice. The equations presented in a compact form

Xianzhe Dai, Weiping Zhang

For a continuous curve of families of Dirac type operators we define a higher spectral flow as a $K$-group element. We show that this higher spectral flow can be computed analytically by $\heta$-forms, and is related to the family index in the same way as the spectral flow is related to the index. We introduce a notion of Toeplitz family and relate its index

T. E. Mason, G. Aeppli

We review the results of recent studies of the elastic and inelastic neutron scattering from a variety of heavy fermion compounds. This class of materials exhibits a rich variety of ground states: antiferromagnetically ordered, superconducting, semiconducting, and paramagnetic. Neutron scattering from single crystals and powders has been a productive tool fo

Vidar Gudmundsson, Rolf R. Gerhardts

The far-infrared absorption of a periodically modulated two-dimensional electron gas in a perpendicular constant magnetic field is calculated self-consistently within the Hartree approximation. For vanishing modulation the magnetoplasmon dispersion shows simple anticrossings with harmonics of the cyclotron resonance, as expected. For increasing modulation we

Luigi Amico, Giuseppe Falci, Rosario Fazio, Gaetano Giaquinta

We study the phase diagram and the excitation spectra of an array of small Josephson junctions at $f=1/2$ and arbitrary charge frustration. We find that the supersolid region in the phase diagram is larger than the correspondent region at $f=0$ and it includes two different phases.In the chiral supersolid (SS) charges and vortices are arranged in a checkerbo

S. Goedecker, C. J. Umrigar

We calculate the electronic structure of several atoms and small molecules by direct minimization of the Self-Interaction Corrected Local Density Approximation (SIC-LDA) functional. To do this we first derive an expression for the gradient of this functional under the constraint that the orbitals be orthogonal and show that previously given expressions do no

T. Fukui, N. Kawakami

The spectral flow in the supersymmetric {\it t-J} model with $1/r^2$ interaction is studied by analyzing the exact spectrum with twisted boundary conditions. The spectral flows for the charge and spin sectors are shown to nicely fit in with the motif picture in the asymptotic Bethe ansatz. Although fractional exclusion statistics for the spin sector clearly

Ross H. McKenzie, G. J. Athas, J. S. Brooks, R. G. Clark

The magnetic field dependence of the resistance of (BEDT-TTF)$_2$MHg(SCN)$_4$[M=K,Rb,Tl] in the density-wave phase is explained in terms of a simple model involving magnetic breakdown and a reconstructed Fermi surface. The theory is compared to measurements in pulsed magnetic fields up to 51 T. The value implied for the scattering time is consistent with ind

Jussi Karlgren

Texts exhibit considerable stylistic variation. This paper reports an experiment where a corpus of documents (N= 75 000) is analyzed using various simple stylistic metrics. A subset (n = 1000) of the corpus has been previously assessed to be relevant for answering given information retrieval queries. The experiment shows that this subset differs significantl

Marko Robnik, Luca Salasnich

We perform a systematic WKB expansion to all orders for a one--dimensional system with potential $V(x)=U_0/\cos^2{(αx)}$. We are able to sum the series to the exact energy spectrum. Then we show that any finite order WKB approximation fails to predict the individual energy levels within a vanishing fraction of the mean energy level spacing.

Rachel A. Pildis, Stacy S. McGaugh

Suto et al. (1996, astro-ph/9602061 and ApJ, 461, L33) have suggested that an X-ray halo in the Local Group might explain both the observed low-energy excess in the X-ray background and the quadrupole anisotropy in the cosmic microwave background. Recent observations of poor groups of galaxies by the ROSAT PSPC set reasonable limits on how extensive and dens

Heino Falcke, Andrew S. Wilson, Chris Simpson, Gary A. Bower

We present HST/WFPC2 images of the narrow line region (NLR) of the Seyfert 2 galaxy ESO 428-G14 (0714-2914, M4-1). The NLR consists of many individual, thin strands, which are very closely related to the radio jet and produce a highly complex yet ordered structure. We find that the jet is two-sided with a double-helix of emission-line gas apparently wrapped

L. Infante, D. F. de Mello, F. Menanteau

The 2-point angular correlation function of galaxies, \wt, has been computed on equatorial fields observed with the CTIO 4m prime focus, within a total area of 2.31 deg$^2$. In the magnitude range $19\le m_R \le 21.5$, corresponding to $<z>\approx 0.35$, we find an excess of power in \wt at scales $2&#39;&#39;\leθ\le6&#39;&#39;$ over what would be expected f

R. Cowsik, Charu Ratnam, P. Bhattacharjee

In a recent Comment on our Letter (Phys. Rev. Lett, Vol 76, p 3886 (1996); astro-ph/9605001) Evans (astro-ph/9606155) has raised some issues concerning the specific choice of the distribution function used in our calculation. He has also raised questions concerning the numerical validity of our results. We clarify these issues and show that Evans&#39;s criti

N. Zacharias, M. I. Zacharias, G. G. Douglass, G. L. Wycoff

A first version of the Twin Astrographic Catalog (TAC) of positions for 705,679 stars within $-18^{\circ} \le δ\le 90^{\circ}$ has been produced. The sky coverage of the TAC is complete to over 90\% in that area. The limiting magnitude is about B=11.5. Positions are based on $4912$ plates taken with the U.S. Naval Observatory Twin Astrograph (blue, yellow le

Brian R. Greene, David R. Morrison, Cumrun Vafa

We study the geometric realization of the Higgs phenomenon in type II string compactifications on Calabi--Yau manifolds. The string description is most directly phrased in terms of confinement of magnetic flux, with magnetic charged states arising from D-branes wrapped around chains as opposed to cycles. The rest of the closed cycle of the D-brane worldvolum

G. Lazarides, R. K. Schaefer, Q. Shafi

We consider a supersymmetric model of inflation in which the primordial density fluctuations are nearly scale invariant (the spectral index n is approximately 0.98) with amplitude proportional to (M/M_{Planck})^2, where M ~ 10^{16} GeV denotes the scale of the gauge symmetry breaking associated with inflation. The 60 or so e-foldings take place when all rele

S. A. Abel, J. -M. Frere

We show that all CP violation in the MSSM could originate in the supersymmetry breaking sector rather than the CKM matrix, and discuss the important consequences for $B$-physics.

Michael Martin Nieto, D. Rodney Truax

In this article, results from the previous paper (I) are applied to calculations of squeezed states for such well-known systems as the harmonic oscillator, free particle, linear potential, oscillator with a uniform driving force, and repulsive oscillator. For each example, expressions for the expectation values of position and momentum are derived in terms o

Michael Martin Nieto, D. Rodney Truax

In this paper we use the Lie algebra of space-time symmetries to construct states which are solutions to the time-dependent Schrödinger equation for systems with potentials $V(x,τ)=g^{(2)}(τ)x^2+g^{(1)}(τ)x +g^{(0)}(τ)$. We describe a set of number-operator eigenstates states, $\{Ψ_n(x,τ)\}$, that form a complete set of states but which, however, are usually

J. Finkelstein

Interpretational questions that arise in the Consistent Histories formulation of quantum mechanics are illustrated by the familiar example of a beam passing through multiple slits.

Andrew Kricker, Bill Spence

Using a vanishing condition on certain combinations of components of the Jones polynomial for algebraically split links we show that Ohtsuki&#39;s invariants of integral homology three spheres are of finite type. We further show that the corresponding manifold weight system is given by the expected Lie algebraic construction.

Chungsik Song, Volker Koch

Temperature effects on the electromagnetic couplings of pions in hot hadronic matter are studied with an effective chiral Lagrangian. We show that the Ward-Takahashi identity is satisfied at non-zero temperature in the soft pion limit. The in-medium electromagnetic form factor of the pion is obtained in the time-like region and shown to be reduced in magnitu

O. Benhar, S. Fantoni, N. N. Nikolaev, J. Speth

We develop the Glauber theory description of initial- and final-state interactions (IFSI) in quasielastic A(p,2p) scattering. We study the IFSI-distortion effects both for the inclusive and exclusive conditions. In inclusive reaction the important new effect is an interaction between the two sets of the trajectories which enter the calculation of IFSI-distor

T. K. Choi, M. Maruyama, F. Takagi

We study the nuclear stopping in high energy nuclear collisions using the constituent quark model. It is assumed that wounded nucleons with different number of interacted quarks hadronize in different ways. The probabilities of having such wounded nucleons are evaluated for proton-proton, proton-nucleus and nucleus-nucleus collisions. After examining our mod

H. Beer, C. Coceva, P. V. Sedyshev, Yu. P. Popov

At the Karlsruhe pulsed 3.75\,MV Van de Graaff accelerator the thermonuclear $^{48}$Ca(n,$γ$)$^{49}$Ca(8.72\,min) cross section was measured by the fast cyclic activation technique via the 3084.5\,keV $γ$-ray line of the $^{49}$Ca-decay. Samples of CaCO$_3$ enriched in $^{48}$Ca by 77.87\,\% were irradiated between two gold foils which served as capture stan

Andrew E. Chubykalo, Roman Smirnov-Rueda

Some mathematical inconsistencies in the conventional form of Maxwell&#39;s equations extended by Lorentz for a single charge system are discussed. To surmount these in framework of Maxwellian theory, a novel convection displacement current is considered as additional and complementary to the famous Maxwell displacement current. It is shown that this form of

D. Karczewska, R. Manka

The sphaleron type solution in the electroweak theory, generalized to include the dilaton field, is examined. The solutions describe both the variarions of Higgs and Gauge fields inside the sphaleron and the shape of the dilaton cloud surrounding the sphaleron. Such a cloud is large and extends far outside. These phenomena may play an important role during t

Francesco Toppan

It is shown that supersymmetric integrable models in two dimensions, both relativistic (i.e. super-Toda type theories) and non-relativistic (reductions of super-KP hierarchies) can be associated to general Poisson-brackets structures given by superaffinizations of any bosonic Lie or any super-Lie algebra. This result allows enlarging the set of supersymmetri

Hans-Christian Pauli

The canonical front form Hamiltonian for non-Abelian SU(N) gauge theory in 3+1 dimensions is mapped on an effective Hamiltonian which acts only in the Fock space of one quark and one antiquark. The approach is non-perturbative and exact. It is based on Discretized Light-Cone Quantization and the Method of Iterated Resolvents. The method resums the diagrams o

E. Kiritsis, C. Kounnas, P. M. Petropoulos, J. Rizos

In the framework of heterotic compactifications, we consider the one-loop corrections to the gauge couplings, which were shown to be free of any infra-red ambiguity. For a class of N=2 models, namely those that are obtained by toroidal compactification to four dimensions of generic six-dimensional N=1 ground states, we give an explicit formula for the gauge-

R. S. Ward

The O(3) sigma model and abelian Higgs model in two space dimensions admit topological (Bogomol&#39;nyi) lower bounds on their energy. This paper proposes lattice versions of these systems which maintain the Bogomol&#39;nyi bounds. One consequence is that instantons/solitons/vortices on the lattice then have a high degree of stability.

Kazuo Ghoroku, Kazunari Kaneko

The dynamical properties of the gauge theory of Born-Infeld type action, which is expected as the high-energy effective theory, are investigated by adding a complex scalar field to this gauge system. Especially the Coleman-Weinberg mechanism is addressed in this theory.

Bernd Schwesinger

In Skyrme-type models, the leading term of the low-energy photoproduction amplitude is identical to the standard expression and independent of the number of flavors considered, but subleading terms are not.

A. Makhlin

I derive expressions for various correlators of the gauge field and find propagators in a new gauge A^τ=0. This gauge is a part of the wedge form of relativistic dynamics suggested earlier as the tool for the study of quantum dynamics in collisions of hadrons at extremely high energies and in ultrarelativistic heavy ion collisions. The new gauge puts the qua

A. Makhlin

The origin of the spurious poles of the gauge field propagators in the temporal axial and the null-plane gauges is discussed. The conclusion is that these poles do not require any special prescription. They are a manifestation of the fact that that the gauge field acquires a static configuration.

A. Makhlin

It is commonly accepted that in hadronic or nuclear collisions at extremely high energies the shortest scales are explored. At the classical level, this property of the interaction is closely related to the Lorentz contraction of the fields of colliding particles which provides instantaneous switching the interaction on. I argue that the underlying quantum d

Geoffrey B. West

Theoretical ideas related to the existence of glueballs in QCD are reviewed. These include non-perturbative phenomena such as confinement, instantons, vacuum condensates and renormalons. We also discuss glueball dominance of the trace of the stress-tensor, the mass content of the nucleon and a theorem on the lightest glueball state.

Alexander Bochkarev

Physical contribution of the high-energy part of hadronic spectrum is incorporated to describe the short-distance part of the correlator of heavy-quark currents obtained by quenched Monte-Carlo on a $8^3*16$- and $16^3*32$-lattices for $β= \{ 6, 6.3 \}$. The lattice artifacts in the short-distance behavior of that correlator are isolated. The physical short-

Michael C. Birse, Thomas D. Cohen, Judith A. McGovern

Simple group-theoretical arguments are used to demonstrated that in the high temperature (chirally restored) phase of QCD with N massless flavours, all n-point correlation functions of quark bilinears are invariant under U(1) axial transformations provided n < N. In particular this implies that the two-point correlation function in the eta&#39; channel is id

Ann E Nelson

We should be taking advantage of recent gains in our nonperturbative understanding of supersymmetric gauge theories to find the ``standard&#39;&#39; model of of dynamical supersymmetry breaking, and possibly of flavor as well. As an illustration of the possibilities for understanding the flavor hierarchy, I describe a realistic, renormalizable, supersymmetri

T. K. Gaisser, M. Honda, K. Kasahara, H. Lee

We compare several different calculations of the atmospheric neutrino flux in the energy range relevant for contained neutrino interactions, and we identify the major sources of difference among the calculations. We find nothing that would affect the predicted ratio of $ν_e/ν_μ$, which is nearly the same in all calculations. Significant differences in normal

Siwen Wang, Leonard S. Kisslinger

In a study of the elastic pion form factor for large momentum transfers based on a modified perturbative QCD (PQCD) approach we have included helicity components that are customarily neglected. Along with the inclusion of transverse momentum, this gives a large suppression of the form factor from the prediction of the original hard scattering model based on

G. P. Salam

This talk reviews briefly some of the main results of the small-x dipole formulation with regards to unitarity corrections. It illustrates the correspondence between unitarity and saturation corrections in the dipole approach and multiple t-channel pomeron exchange in the traditional BFKL view, and discusses how one can estimate and understand the effects of

A. E. Bergan

Within the Chiral Quark Model we have calculated the effect of non-factorizable $\langle G^3 \rangle$ contribution to the $B_K$ parameter. When all diagrams are summed, a vanishing result is obtained.

Jun Cao, Hui-fang Wu

Based on a Perturbative QCD analysis of the deuteron form factor, a model for the reduced form factor is suggested. The numerical result is consistent with the data in the intermediate energy region.

Christoph Greub, Soo-Jong Rey

A measurement of the hadron energy spectrum in inclusive semileptonic $B$ decays is proposed as a viable method for extracting $|V_{ub}|$. Compared to the traditional energy spectrum of the charged lepton, the hadron energy spectrum exhibits kinematical advantages such as a wider energy window and a larger signal branching fraction. It is emphasized that the

Philippe de Forcrand, Margarita Garcia Perez, Ion-Olimpiu Stamatescu

We use a cooling algorithm based on an improved action with scale invariant instanton solutions, which needs no monitoring or calibration and has a inherent cut off for dislocations. We present results for SU(2) Yang-Mills theory where the method provides good susceptibility data and physical size distributions of instantons.