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Calculations of precursor propagation in dispersive dielectrics.

Description: The present study is a numerical investigation of the propagation of electromagnetic transients in dispersive media. It considers propagation in water using Debye and composite Rocard-Powles-Lorentz models for the complex permittivity. The study addresses this question: For practical transmitted spectra, does precursor propagation provide any features that can be used to advantage over conventional signal propagation in models of dispersive media of interest? A companion experimental study is currently in progress that will attempt to measure the effects studied here.
Date: August 1, 2003
Creator: Bacon, Larry Donald
Partner: UNT Libraries Government Documents Department

Metaplections and fractional statistics

Description: The spinor representations of the orthosymplectic Lie supergroup, OSp(r/2m,R), are used as a means to induce new fractional statistics in certain (2 + 1)-dimensional models.
Date: January 1, 1991
Creator: Castano, D.J.
Partner: UNT Libraries Government Documents Department

A higher derivative view of the arc length and area actions

Description: Higher derivative versions of the arc length and area actions are presented. The higher derivative theories are equivalent with the corresponding lower derivative theories in absence of interactions. The extra degrees of freedom associated with the higher derivatives are pure gauge due to a hidden reparametrization invariance these theories possess. The extra degrees of freedom are no longer pure gauge in the presence of background fields and the equivalence no longer holds. A string version of Wigner's continuous spin particle is also noted.
Date: January 1, 1991
Creator: Zoller, D.
Partner: UNT Libraries Government Documents Department

Research in the theory of condensed matter and elementary particles. Progress report

Description: Brief progress summaries are given on the dynamics of Polyakov's string, the problem of putting chiral fermions on the lattice, order and disorder that arises in two-dimensional systems with incommensurate phases, gauge theory in 1 + 1 dimension with quarks being treated as classical particles, the finite temperature deconfining transition in the 2 + 1 dimension compact U(1) lattice gauge theory (the Polyakov model), the Monte Carlo renormalization group treatment of the O(3) nonlinear sigma model, Yang-Mills-Higgs system in 2 + 1 dim., large N expansion for biquadratic spin systems, and variational method for quenched Parisi model. Publications are listed. 27 refs. (WHK)
Date: January 1, 1981
Partner: UNT Libraries Government Documents Department

Theory of elementary particles. Annual report, 1979. [Univ. of Oregon]

Description: Activities for 1979 in the following areas are very briefly summarized: dileptonic processes (hadron-hadron collisions, photon-photon collisions, leading log approximation), ladder approximations in QCD, quark models (clustering, the recombination model), weak interaction phenomenology, nonleptonic decays, grand unification, neutrino pairing, polarization phenomena (general theory, polarization studies of the deuteron, lambda polarization), deuteron targets, and electron beams. There are no data. (RWR)
Date: October 1, 1979
Partner: UNT Libraries Government Documents Department

(Topics in theoretical physics). Progress report

Description: Progress is reported in these areas: supersymmetry and conformal invariance and new structures in two dimensional critical phenomena; spinor fields and new applications and techniques for studying Ising model correlation factors; superstring compactification and high energy physics applications for novel two dimensional critical points; ordered and disordered spatial structure in dynamical systems; and fermion-boson mass relations in BCS type theories. Research is proposed in covariant formulation of the superstring, topics in superconformal field theory and new structures in two dimensional critical phenomena, ordered and disordered spatial structure in dynamical systems, and field theory over Galois fields. 48 refs. (LEW)
Date: January 1, 1985
Partner: UNT Libraries Government Documents Department

(Research in the theory of condensed matter and elementary particles. ) Progress report

Description: Progress is summarized in these areas: a new formulation of two dimensional critical phenomena and string theory, supersymmetric critical phenomena and string compactification, conformal field theory on orbifolds, Gaussian models with twisted boundary conditions, modular invariance and supersymmetric critical phenomena, critical indices, conformal invariance, and current algebra, renormalization group fixed points and the string equation of motion, fermionic string field theory, N = 2 super Riemann surfaces, the spinor field in covariant superstring theory, covariant quantization of superstrings, models of aggregation, and quasi-supersymmetry in the BCS mechanism. Further work is proposed in the areas of two dimensional critical phenomena, two dimensional conformal field theory and string theory, the physics of computation, models of aggregation, and the many vortex Aharonov-Bohm problem. 57 refs. (LEW)
Date: January 1, 1986
Partner: UNT Libraries Government Documents Department

Research in the theory of condensed matter and elementary particles. (Progress report)

Description: The proposed research is concerned with problems occupying the common ground between quantum field theory and statistical mechanics. The topics under investigation include: superconformal field theory in two dimensions, its relationship to two dimensional critical phenomena and its applications in string theory; the covariant formulation of the superstring theory; formation of large-scale structures and spatial chaos in dynamical systems; fermion-boson mass relations in BCS type theories; and properties of quantum field theories defined over galois fields. 37 refs.
Date: January 1, 1985
Partner: UNT Libraries Government Documents Department

Do fermion-pseudoparticle interactions generate quark masses

Description: It is shown that pseudoparticle solutions with integer winding number do not generate mass terms or breaking of chiral SU(N) in theories with a nontrivial flavor group.
Date: January 1, 1977
Creator: Hietarinta, J.; Palmer, W.F. & Pinsky, S.S.
Partner: UNT Libraries Government Documents Department

Argonne National Laboratory, High Energy Physics Division: Semiannual report of research activities, July 1, 1986-December 31, 1986

Description: This paper discusses the research activity of the High Energy Physics Division at the Argonne National Laboratory for the period, July 1986-December 1986. Some of the topics included in this report are: high resolution spectrometers, computational physics, spin physics, string theories, lattice gauge theory, proton decay, symmetry breaking, heavy flavor production, massive lepton pair production, collider physics, field theories, proton sources, and facility development. (LSP)
Date: January 1, 1987
Partner: UNT Libraries Government Documents Department

Construction of Lax operators from weight diagrams

Description: We show that cyclic weight diagrams corresponding to representations of affine Lie algebras allow one to read-off the associated Lax operator. The resultant Lax pair generates the modified KdV equations, and have been shown in some cases to produce acceptable solutions of the string equation of matrix models.
Date: May 1, 1991
Creator: Carbon, S.L. & Piard, E.J.
Partner: UNT Libraries Government Documents Department

Old and new physics in nucleon spin structure

Description: EMC implies quarks carry very little of the proton spin. (G{sub A}/G{sub V}){sub n{yields}p} implies that valence quarks carry 70% of the spin, but disagrees with SU(6). (G{sub A}/G{sub V}){sub {Sigma}{minus}{yields}n} agrees strinkingly with SU(6). All semileptonic decay data can be fit by SU(3), but no model fits the data by breaking SU(6) without also breaking SU(3). Considerable data on hadron masses and magnetic moments are fit by a simple constituent quark model with only constituent quarks. A toy model for the proton with valence quarks and sea fits nearly everything.
Date: January 1, 1991
Creator: Lipkin, H.J. (Weizmann Inst. of Science, Rehovoth (Israel). Dept of Physics Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory)
Partner: UNT Libraries Government Documents Department

Studies in theoretical high energy particle physics

Description: This report discusses research in string theory; solitons; supersymmetry; conformed field theory; and quarks.
Date: January 1, 1992
Creator: Aratyn, H.; Brekke, L.; Keung, Wai-Yee & Sukhatme, U.
Partner: UNT Libraries Government Documents Department

Studies in theoretical particle physics

Description: This proposal focuses on research on three distinct areas of particle physics: (1) Nonperturbative QCD. I tend to continue work on analytic modelling of nonperturbative effects in the strong interactions. I have been investigating the theoretical connection between the nonrelativistic quark model and QCD. The primary motivation has been to understand the experimental observation of nonzero matrix elements involving current strange quarks in ordinary matter -- which in the quark model has no strange quark component. This has led to my present work on understanding constituent (quark model) quarks as collective excitations of QCD degrees of freedom. (2) Weak Scale Baryogenesis. A continuation of work on baryogenesis in the early universe from weak interactions. In particular, an investigation of baryogenesis occurring during the weak phase transition through anomalous baryon violating processes in the standard model of weak interactions. (3) Flavor and Compositeness. Further investigation of a new mechanism that I recently discovered for dynamical mass generation for fermions, which naturally leads to a family hierarchy structure. A discussion of recent past work is found in the next section, followed by an outline of the proposed research. A recent publication from each of these three areas is attached to this proposal.
Date: July 1, 1991
Creator: Kaplan, D.B.
Partner: UNT Libraries Government Documents Department

Supermatrix models

Description: Radom matrix models based on an integral over supermatrices are proposed as a natural extension of bosonic matrix models. The subtle nature of superspace integration allows these models to have very different properties from the analogous bosonic models. Two choices of integration slice are investigated. One leads to a perturbative structure which is reminiscent of, and perhaps identical to, the usual Hermitian matrix models. Another leads to an eigenvalue reduction which can be described by a two component plasma in one dimension. A stationary point of the model is described.
Date: May 1, 1991
Creator: Yost, S.A.
Partner: UNT Libraries Government Documents Department

Study of heavy flavored particles

Description: This report discusses progress on the following topics: time-of- flight system; charmed baryon production and decays; D decays to baryons; measurement of sigma plus particles magnetic moments; and strong interaction coupling. (LSP)
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department

Segregation of quarks within the neutron

Description: Measurements of the nucleon form factor and structure function seem to indicate an inhomogeneous distribution of flavor, charge and spin within the nucleon. It is argued that the ordinary three-quark model with a spin-spin force of the type suggested by QCD can explain the inhomogeneity as seen at different resolutions. This agreement suggests a specific bound quark picture of the nucleon structure with a positive core of u and d quarks in a spin-O state of ms radius 0.17 {plus minus} 0.01 fm{sup 2} and an outer layer of a linear size {approximately} 1 fm where the polarized u (in the proton) or d (in the neutron) is orbiting. 21 refs., 3 figs.
Date: January 1, 1991
Creator: Dziembowski, Z.
Partner: UNT Libraries Government Documents Department

High energy physics studies. Progress report. Part I. Experimental program. Part II. Theoretical program. [Summaries of research activities at Ohio State University]

Description: Experimental Program: assembly of an experiment as Fermilab E-531 to measure decay lifetimes, with tagged emulsion of charmed particles produced by high energy neutrinos was finished, and data taking now is in progress. An experiment to measure prompt neutrino production at Fermilab, E-613, was approved and detailed design of it is continuing. Search for parity violation in scattering of polarized protons, an experiment E-446-ZGS at ANL, was performed with the sensitivity of 10/sup -6/ for detection of that process and yielded null results. Another run with improved sensitivity of 10/sup -7/ is in preparation. Data analysis of the neutrino experiment E-310 at Fermilab will continue. Trimuon events, a new discovery, were identified in those data. Analysis of data on meson production from experiments performed at the ZGS--ANL, E-397, E-420 and E-428, with charged and neutral spectrometer will continue. A new relatively broad resonance (T approx. 70 MeV) with quantum numbers IJ/sup P/ = 00/sup -1/ was discovered in the data from E-397. Analysis of beta decay of polarized ..sigma../sup -/ hyperons is in progress. Participation in the design of the experimental areas for the Isabelle colliding proton beam accelerator will continue. Theoretical Program: topics which will be investigated in the coming year are: the instanton-anti-instanton QCD gauge fields, discrete symmetries which may determine quark masses in the SU(2) x U(1) model, calculation of charmed meson production in e/sup +/e/sup -/ collisions and formation of gluon jets, Higgs boson production in pp collisions, calculation of Higgs boson mass in terms of vector boson mass, study of Lagrangians with gauge and Higgs scalar fields, investigation of Faddeev--Popov determinants as related to quantum chromodynamics, a study of quantum flavor dynamics and anomalies in the axial vector Ward identity and a study of super symmetry as a part of a realistic model of leptonic ...
Date: January 1, 1978
Creator: Romanowski, T.A.; Tanaka, K. & Wada, W.W.
Partner: UNT Libraries Government Documents Department

Theoretical particle physics

Description: We have carried out research in lattice gauge theory, superstring theory, supersymmetry, the solar neutrino puzzle, QCD perturbation theory, and phenomenological models of hadrons. In this report, we summarize our work in each of these areas.
Date: April 1, 1992
Creator: Gottlieb, S.A.; Hendry, A.W.; Kostelecky, V.A. & Lichtenberg, D.B.
Partner: UNT Libraries Government Documents Department

Color magnetism in pion photoproduction and radiative delta decay

Description: We use the extant multipole data base to extract the ..gamma..N-..delta.. transition amplitudes, using the phenomenology of the effective Lagrangian approach. We find evidence for hadronic color magnetism in the radiative delta decay amplitudes. 24 refs., 2 tabs.
Date: January 1, 1987
Creator: Mukhopadhyay, N. C. & Davidson, R.
Partner: UNT Libraries Government Documents Department

Zero-point energy in bag models

Description: The zero-point (Casimir) energy of free vector (gluon) fields confined to a spherical cavity (bag) is computed. With a suitable renormalization the result for eight gluons is E = + 0.51/a. This result is substantially larger than that for a spherical shell (where both interior and exterior modes are present), and so affects Johnson's model of the QCD vacuum. It is also smaller than, and of opposite sign to, the value used in bag model phenomenology, so it will have important implications there. 1 figure.
Date: January 1, 1979
Creator: Milton, K.A.
Partner: UNT Libraries Government Documents Department