200 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Composite Models"  
Results: 1 - 24 next
open access

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 c… more
Date: August 1, 2003
Creator: Bacon, Larry Donald
Partner: UNT Libraries Government Documents Department
open access

Evaluation of the 1998 Predictions of the Run-Timing of Wild Migrant Yearling Chinook and Water Quality at Multiple Locations on the Snake and Columbia Rivers using CRiSP/RealTime, 1998 Technical Report.

Description: Since 1988, wild salmon have been PIT-tagged through monitoring and research programs conducted by the Columbia River fisheries agencies and Tribes. Workers at the University of Washington have used detection data at Lower Granite Dam to generate predictions of arrival distributions for various stocks at the dam. The prediction tool is known as RealTime. In 1996, RealTime predictions were linked to a downstream migration model, CRiSP.1. The composite model, known as CRiSP/RealTime, predicts the… more
Date: July 21, 1999
Creator: Beer, W. Nicholas; Hayes, Joshua A. & Shaw, Pamela
Partner: UNT Libraries Government Documents Department
open access

Sensitivity to quark and lepton compositeness at the Tevatron

Description: We present a study of the sensitivity of CDF to quark and lepton compositeness assuming 2 fb{sup -1} (Run II) and 30 fb{sup -1} (TeV33) of integrated luminosity for future Tevatron collider runs. We calculate the expected number of Drell-Yan dielectron events in the standard model, and compare it to the predicted number of events from a {ital q{anti q}} {r_arrow} {ital e{anti e}} left-handed contact interaction, as a function of dielectron invariant mass, for various values of the compositeness… more
Date: October 1, 1996
Creator: de Barbaro, P.; Bodek, A.; Kim, B.J.; Fan, Q. & Harris, R.
Partner: UNT Libraries Government Documents Department
open access

Theoretical high energy physics research at the University of Chicago. Progress report, October 1, 1992--April 30, 1993

Description: Brief narrative descriptions of work performed are given on numerous topics including the following: CP violation, Cabibbo--Kobayashi--Maskawa matrix, and B physics; radiative corrections and electroweak observables; heavy quark symmetry; heavy meson spectroscopy; composite models of quarks and leptons; supersymmetric quantum mechanics, inverse scattering, and the vertex operator; cosmological constraints on lepton-number violation in SO(10) models; black hole evaporation; the light cone in str… more
Date: April 1, 1993
Creator: Rosner, J. L.; Martinec, E. J. & Sachs, R. G.
Partner: UNT Libraries Government Documents Department
open access

Topics in gauge theories and the unification of elementary particle interactions. [Northeastern Univ. , Boston Massachusetts]

Description: Work done on the following topics is summarized: (1) Coulomb potential in QED on the lattice; (2) Weyl cosmic strings and their consequences; (3) Interference between past and future events in [phi] [yields] K[bar K]; (4) Quantum effects of strong classical electromagnetic fields; (5) Application of computer algebra to calculations in supersymmetry and supergravity; (6) numerical studies of classical scalar [phi][sup 4] field theory and related nonlinear [sigma]-models; (7) Analysis of a cubic … more
Date: February 1, 1993
Creator: Srivastava, Y. N. & Vaughn, M. T.
Partner: UNT Libraries Government Documents Department
open access

[Mathematics and string theory]

Description: Work on this grant was centered on connections between non- commutative geometry and physics. Topics covered included: cyclic cohomology, non-commutative manifolds, index theory, reflection positivity, space quantization, quantum groups, number theory, etc.
Date: January 1, 1993
Creator: Jaffe, A. & Yau, Shing-Tung.
Partner: UNT Libraries Government Documents Department
open access

Theory of photon and electron induced reactions. [Inst. of Nuclear and Particle Physics, Dept. of Physics and Astronomy, Ohio Univ. , Athens, Ohio]

Description: Theoretical work is reported on the following topics: photo- and electroproduction of mesons by the ([gamma],[pi][sup [minus]]p) reactions on [sup 12]C and [sup 16]O; Coulomb distortion effects on (e,e[prime][gamma]) and on inclusive (e,e[prime]) and exclusive (e,e[prime]p) scattering in the quasi-elastic region for [sup 40]Ca, [sup 208]Pb, and [sup 238]U; relativistic structure calculations in which the basic lagrangian is an extension of the [sigma][endash][omega] model in which the nucleons … more
Date: January 1, 1993
Creator: Onley, D. S. & Wright, L. E.
Partner: UNT Libraries Government Documents Department
open access

A detailed study of nonperturbative solutions of two-body Dirac equations

Description: In quark model calculations of the meson spectrums fully covariant two-body Dirac equations dictated by Dirac's relativistic constraint mechanics gave a good fit to the entire meson mass spectrum for light quark mesons as well as heavy quark mesons with constituent world scalar and vector potentials depending on just one or two parameters. In this paper, we investigate the properties of these equations that made them work so well by solving them numerically for quantum electrodynamics (QED) and… more
Date: December 1, 1992
Creator: Crater, H. W.; Becker, R. L.; Wong, C. Y. & Van Alstine, P.
Partner: UNT Libraries Government Documents Department
open access

High Energy Physics Program at Texas A and M University

Description: The high energy physics program has continued its experimental activities over. In CDF, the Texas A M group has led an effort to design an upgrade for the silicon vertex detector, and is currently working with the rest of the collaboration on the next major data taking run. In MACRO, work was done on the development of the final version of the wave form digitizing system being implemented for the entire scintillator system. This work is nearing completion, and the system is expected to be up an… more
Date: November 1992
Partner: UNT Libraries Government Documents Department
open access

The SU(3)-Nambu-Jona-Lasinio soliton in the collective quantization formulation

Description: On grounds of a semibosonized Nambu-Jona-Lasinio model, which has SU(3){sub R}{circle times}SU(3){sub L}-symmetry in the chiral limit, mass splittings for spin 1/2 and spin 3/2 baryons are studied in the presence of an explicit chiral symmetry breaking strange quark mass. To this aim these strangeness carrying baryons are understood as SU(3)-rotational excitations of an SU(2)-embedded soliton solution. Therefore, within the framework of collective quantization, the fermion determinant with the … more
Date: June 11, 1992
Creator: Blotz, A.; Goeke, K. (Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory Inst. fuer Theoretische Physik 2, Ruhr-Univ. Bochum (Germany)); Diakonov, D.; Petrov, V.; Pobylitsa, P.V. (St. Petersburg Nuclear Physics Inst., Gatchina (Russia)) & Park, N.W. (Inst. fuer Theoretische Physik 2, Ruhr-Univ. Bochum (Germany) Center for Theoretical Physics, Seoul National Univ. (Korea, Republic
Partner: UNT Libraries Government Documents Department
open access

A Cloudy Quark Bag Model of S, P, and D wave interactions for the coupled channel antikaon-nucleon system

Description: The Cloudy Quark Bag Model is extended from S-wave to P- and D-wave. The parameters of the model are determined by K{sup {minus}}p scattering cross section data, K{sup {minus}}p {yields}{Sigma}{pi}{pi}{pi} production data, K{sup {minus}}p threshold branching ratio data, and K{sup {minus}}p {yields}{Lambda}{pi}{pi}{pi} production data. The resonance structure of the {Lambda}(1405), {Sigma}(1385), and {Lambda}(1520) are studied in the model. The shift and width of kaonic hydrogen are calculated u… more
Date: May 15, 1992
Creator: He, Guangliang.
Partner: UNT Libraries Government Documents Department
open access

(Research in elementary particles and interactions). [1992]

Description: Research of the Yale University groups in the areas of elementary particles and their interactions are outlined. Work on the following topics is reported: development of CDF trigger system; SSC detector development; study of heavy flavors at TPL; search for composite objects produced in relativistic heavy-ion collisions; high-energy polarized lepton-nucleon scattering; rare K{sup +} decays; unpolarized high-energy muon scattering; muon anomalous magnetic moment; theoretical high-energy physics … more
Date: May 1, 1992
Creator: Adair, R.; Sandweiss, J. & Schmidt, M.
Partner: UNT Libraries Government Documents Department
open access

Theoretical Studies in Nuclear Reactions and Nuclear Structure

Description: Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has … more
Date: May 1, 1992
Partner: UNT Libraries Government Documents Department
open access

Comment on Flavor-Changing Processes and CP Violation in the S Sub 3 Times Z Sub 3 Model''

Description: Deshpande, Gupta and Pal neglected the presence of a complex phase in the mass matrix and in the Yukawa coupling matrices of the down-type quarks I argue that phase should not be neglected, because it can explain the observed CP violation. The mechanism of CP violation considered by those authors may certainly be present, but for simplicity one may want to eliminate it, by restricting the soft-breaking sector of the Higgs potential in such a way that complex Higgs bosons propagators do not occu… more
Date: April 28, 1992
Creator: Lavoura, L.
Partner: UNT Libraries Government Documents Department
open access

Theoretical high energy physics research at the University of Chicago, Task A

Description: This report discusses research conducted at the University of Chicago in theoretical high energy physics. Some of the areas included in this report are: cp violation and cabibbo-kobayashi-maskawa matrix; radiative corrections and electroweak observables; heavy quark symmetry; heavy meson spectroscopy; hadronic string theory; composite models of quarks and leptons; and pedagogical effects. (LSP)
Date: April 1, 1992
Creator: Rosner, J.L.; Martinec, E.J. & Sachs, R.G.
Partner: UNT Libraries Government Documents Department
open access

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
open access

Intermediate/high energy nuclear physics

Description: This report discusses progress on the following research: quark cluster model; solving quantum field theories in non-perturbative regime;relativistic wave equations, quarkonia and electron-positron resonances; nuclear dependence at large transverse momentum; factorization at the order of power corrections; single-spin asymmetries; and hadronic photon production. (LSP)
Date: January 1, 1992
Creator: Vary, J.P.
Partner: UNT Libraries Government Documents Department
open access

Intermediate scales of symmetry breaking in Calabi-Yau models

Description: We discuss the generation of large intermediate scales of symmetry breaking in grand unification models suggested by the heterotic string. We analyze on dimensional grounds a particular scenario where one flat direction in the effective potential defines two different scales of gauge-symmetry breaking at very high energies ({approx}0(10{sup 15}GeV)). This mechanism implies the presence of one light (0(1 TeV)) nonchiral neutrino. The size of the observable low-energy effects seems, however, quit… more
Date: January 1, 1992
Creator: Masip, M.
Partner: UNT Libraries Government Documents Department
open access

(Mathematics and string theory)

Description: Over the past year our research activities concentrated around: (1) non-commutative differential geometry and its connections with quantum physics and (2) 2-dimensional(super) conformal quantum field theories and related non-linear {sigma}-models. This paper discusses these topics.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
open access

Metastable Cosmic Strings in Realistic Models

Description: The stability of the electroweak Z-string is investigated at high temperatures. The results show that, while finite temperature corrections can improve the stability of the Z-string, their effect is not strong enough to stabilize the Z-string in the standard electroweak model. Consequently, the Z-string will be unstable even under the conditions present during the electroweak phase transition. Phenomenologically viable models based on the gauge group SU(2)[sub L] [times] SU(2) [sub R] [times] U… more
Date: January 1, 1992
Creator: Holman, R.; Hsu, S.; Vachaspati, T. & Watkins, R.
Partner: UNT Libraries Government Documents Department
open access

[Research programs on elementary particle and field theories and superconductivity]. [Rockefeller Univ]

Description: Research of staff members in theoretical physics is presented in the following areas: super string theory, a new approach to path integrals, new ideas on the renormalization group, nonperturbative chiral gauge theories, the standard model, K meson decays, and the CP problem. Work on high-[Tc] superconductivity and protein folding is also related.
Date: January 1, 1992
Creator: Khuri, N. N.
Partner: UNT Libraries Government Documents Department
open access

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
open access

Theory of photon and electron induced reactions

Description: During the first year and half of the current grant from the Department of Energy we have made considerable progress on the following aspects of the general investigation of electron and photon induced reactions: (1) photo- and electro-production of mesons; (2) Coulomb distortion effects on (e,e{prime}{gamma}) and (e,e{prime}) and (e,e{prime}p) in the quasi-elastic region, (3) studies involving the relativistic shell model, and (4) quark models. We will report on each of these developments in t… more
Date: January 1, 1992
Creator: Onley, D. S. & Wright, L. E.
Partner: UNT Libraries Government Documents Department
open access

Wiggly relativistic strings

Description: We derive the equations of motion for general strings, i.e. strings with arbitrary relation between tension {tau} and energy per unit length {epsilon}. The renormalization of {tau} and {epsilon} results from averaging out small scale wiggles on the string is obtained in the general case to lowest order in the amount of wiggliness. For Nambu-Goto strings we find deviations from the equation of state {epsilon}{tau} = constant in higher orders. Finally we show that under plausible assumptions wigg… more
Date: January 1, 1992
Creator: Hong, Jooyoo; Kim, Jaewan & Sikivie, P.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen