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in subjects: "Standard Model"

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Two exercises in supersymmetry: a low-energy supergravity model and free string field theory

The new features of a supersymmetric standard model in the presence of heavy families are studied. The minimal set of Higgs fields, the desert between the electroweak and the grand unification scale and perturbative values of the dimensionless parameters throughout this region are assumed. Using the numerical as well as the approximate analytic solution of the renormalization group equations, the evolution of all the parameters of the theory are studied in the case of large Yukawa couplings for… more

Date: September 1, 1986

Creator: Preitschopf, C.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

A search for the production of the final states. tau. sup +. tau. sup minus e sup + e sup minus ,. tau. sup +. tau. sup minus. mu. sup +. mu. sup minus , and. tau. sup +. tau. sup minus. pi. sup +. pi. sup minus in e sup + e sup minus collisions at radical s = 29 GeV

We have searched for the reaction e{sup +}e{sup {minus}} {yields} {tau}{sup +}{tau}{sup {minus}}{bar f}f, where f is either an electron, muon, or charged pion, at {radical}s = 29 GeV using the Mark 2 detector at the PEP storage ring. One candidate event is found while 2.3 events are expected from known processes. We would expect to see 11 events if the cross-section for e{sup +}e{sup {minus}} {yields} {tau}{sup +}{tau}{sup {minus}}{bar f}f at {radical}s = 29 GeV were enhanced by the factor of 4… more

Date: July 1, 1991

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Beta-decay beyond the standard model

We discuss possible sources of new interactions in beta-decay and the role of beta-decay experiments in obtaining information on them. 46 refs.

Date: January 1, 1989

Creator: Herczeg, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physics at hadron colliders: Experimental view

The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs.

Date: August 1, 1987

Creator: Siegrist, J.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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B physics theory

The status of the theoretical predictions for loop decays, strategy for precise determination of Vub and the issue of symmetric versus asymmetric machine for a B factory were discussed in the working group. While from our present perspective observation of CP violation appears as the most prominent goal for a B factory, the importance and richness of other B physics was stressed. 23 refs.

Date: December 1, 1989

Creator: Soni, A. (Brookhaven National Lab., Upton, NY (USA). Physics Dept.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physics at TeV e sup + e sup minus linear colliders

A survey is presented of the physics opportunities at TeV e{sup +}e{sup {minus}} linear colliders. Examples are given of physics that might emerge in e{sup +}e{sup {minus}} collisions and in {gamma}{gamma} collisions using the back-scattered laser technique, including {gamma}{gamma} {yields} ZZ scattering as a probe of ultraheavy quanta. The second portion of the talk focuses on physics that must emerge at or below the TeV scale--the mechanism of electroweak symmetry breaking. In particular a v… more

Date: January 1, 1992

Creator: Chanowitz, Michael S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Electron-positron physics at 1 TeV

We discuss the motivation for TeV e/sup +/ e/sup )minus/) linear colliders, some aspects of their design, and the experimental consequences that follow from the design. After a brief discussion of the general physics environment, we consider the discovery potential of these colliders by examining three sample processes: the detection of new heavy leptons, standard Higgs bosons, and charged Higgs bosons. 13 refs., 22 figs., 5 tabs.

Date: March 1, 1988

Creator: Feldman, G. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CP violation

Predictions for CP violation in the three generation Standard Model are reviewed based on what is known about the Cabibbo-Kobayashi-Maskawa matrix. Application to the K and B meson systems are emphasized. 43 refs., 13 figs.

Date: December 1, 1989

Creator: Gilman, Frederick J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A proposal for a precision test of the standard model by neutrino-electron scattering (Large /hacek C/erenkov Detector Project)

A precision measurement of neutrino-electron elastic scattering from a beam stop neutrino source at LAMPF is proposed. The total error in sin/sup 2/theta/sub W/ is estimated to be +-0.89/percent/. The experiment also will be sensitive to neutrino oscillations and supernova-neutrino bursts, and should set improved limits on the neutrino-charge radius and magnetic-dipole moment. The detector consists of a 2.5-million-gallon tank of water with approximately 14,000 photomultiplier tubes lining the … more

Date: April 1, 1988

Creator: Allen, R. C.; Lu, X.-Q.; Gollwitzer, K.; Igo, G. J.; Gulmez, E.; Whitten, C. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Research in theoretical particle physics

This report discusses the following topics in high energy physics: dynamical symmetry breaking and Schwinger-Dyson equation; consistency bound on the minimal model Higgs mass; tests of physics beyond the standard model; particle astrophysics; the interface between perturbative and non-perturbative QCD; cosmology; anisotropy in quantum networks and integer quantum hall behavior; anomalous color transparency; quantum treatment of solitons; color transparency; quantum stabilization of skyrmions; a… more

Date: May 1, 1992

Creator: McKay, D.W.; Munczek, H. & Ralston, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Heavy flavor physics at hadron colliders

The search for the top quark has dominated heavy flavor physics at hadron colliders. For Standard model decay of top the present mass limit in m{sub t} > 89 GeV (95% C.L.). Bottom production cross sections are quite large at hadron colliders, thus providing enough statistics for extensive studies. Results on cross sections, B{sup 0} {minus} {bar B}{sup 0} mixing, exclusive channels and rare B decays will be summarized.

Date: December 1, 1991

Creator: Barbaro-Galtieri, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physics issues for the next linear collider

This article surveys the physics issues to be studied at future e{sup +}e{sup {minus}} colliders, especially in the energy region below 500 GeV. Particular emphasis is given to standard model studies -- precision measurements of the dynamical properties of W bosons and top quarks -- as well as the search for evidence of the Higgs sector.

Date: April 1, 1992

Creator: Peskin, M.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Remarks on Pseudoscalar Higgs Particles

It is suggested that Z decays into three pseudoscalar Higgs particles can be a useful process in search for Higgs particles beyond the standard model. 4 refs., 1 fig.

Date: January 1, 1991

Creator: Li, Ling-Fong

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measuring W photon couplings in a 500 GeV e sup + e sup - collider

The Standard Model gives definite predictions for the W-photon couplings. Measuring them would test an important ingredient of the model. In this work we study the capability of a 500 GeV e{sup +}e{sup {minus}} collider to measure these couplings. We study the most general C and P conserving WW{lambda} vertex. This vertex contains two free parameters, {kappa} and {lambda}. We look at three processes: e{sup +}e{sup {minus}} {yields} W{sup +}W{sup {minus}}, e{lambda} {yields} W{nu} and {lambda}{l… more

Date: August 1, 1991

Creator: Yehudai, E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Plans for polarized beams at the SLC

Precision tests of the electroweak interactions will soon be possible at the SLC and LEP. The SLC will be capable of providing longitudinal polarization of one incoming beam, the electrons, for such tests. Plans at the SLC to provide and monitor these beams are described, and some physics objectives are discussed. 5 refs., 10 figs.

Date: July 1, 1985

Creator: Prescott, Charles Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Construction of relativistic quantum theory: a progress report

We construct the particulate states of quantum physics using a recursive computer program that incorporates non-determinism by means of locally arbitrary choices. Quantum numbers and coupling constants arise from the construction via the unique 4-level combinatorial hierarchy. The construction defines indivisible quantum events with the requisite supraluminal correlations, yet does not allow supraluminal communication. Measurement criteria incorporate c, h-bar and m/sub p/ or (not ''and'') G, c… more

Date: June 1, 1986

Creator: Noyes, H. Pierre

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CP violation in the B system: Physics at a high luminosity B Factory

CP Violation remains one of the unsolved puzzles in particle physics. Measurements of CP violating asymmetries in {beta} meson decay will test the Standard Model of electro-weak interactions and tell whether this phenomenon can be explained simply through the non-zero angles and phase in the CKM matrix. A high luminosity, energy asymmetric e{sup +}e{sup {minus}} storage ring provides the most versatile and best opportunity to measure CP violating effects and to test the consistency of the Stand… more

Date: June 1, 1991

Creator: Lueth, V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

KMC unitarity and K/sup +/ yields. pi. /sup +/. nu. anti. nu

Experimental constraints on the Kobayashi-MaskawaCabibbo (KMC) matrix are surveyed and shown to provide a test of the standard model at the level of its O (..cap alpha..) radioactive corrections. The three generation prediction BR (K/sup +/ ..-->.. ..pi../sup +/..nu..) approx. = (0.35 approx. 3) x 10/sup 10/ is reviewed and the potential for enhancement up to approx. = 3 x 10/sup -9/ due to the fourth generation mixing is described. 19 refs.

Date: June 1, 1986

Creator: Marciano, William J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Research at LAMPF

During the past decade, both the science program and the experimental facilities at LAMPF have undergone some significant changes. This report is a concise description of the current research initiatives and of new directions being proposed for the future research program at LAMPF. Traditionally the LAMPF physics program has explored nuclear systems with hadronic probes: pions, protons, and neutrons. In recent years the exploitation of the intense lepton beams -- neutrinos and muons -- at LAMPF… more

Date: February 1, 1992

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Muonium to antimuonium conversion and the decay. mu. sup + yields e sup +. nu. sub e. nu. sub. mu. in left-right symmetric models

We investigate muonium to antimuonium conversion and the exotic muon decay {mu}{sup +} {r arrow} e{sup +}{bar {upsilon}}{sub e} {epsilon}{sub {mu}} in SU(2){sub L} {times} SU(2){sub R} {times} U(1){sub B-L} models. 7 refs.

Date: January 1, 1991

Creator: Herczeg, P. (Los Alamos National Lab., NM (United States)) & Mohapatra, R.N. (Maryland Univ., College Park, MD (United States). Dept. of Physics and Astronomy)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Is there a P-wave bound state of W sub L W sub L On the dynamical generation of a. rho. meson in the. sigma. model

We investigate the possibility that the Higgs lagrangian predicts the existence of a P-wave W{sub L}W{sub L} resonance. This problem is equivalent to studying the formation of the {rho} meson by the dynamics contained in the {sigma} model. Using the Pade approximation, Basdevant and Lee had claimed that {rho} is generated dynamically. We show that their result, while computationally correct, is not significant, because of the position of the Landau ghost. For the same reason, a W{sub L}W{sub L}… more

Date: October 1, 1991

Creator: Atkinson, D. (Fermi National Accelerator Lab., Batavia, IL (United States) Institute for Theoretical Physics, Groningen, The Netherlands (NL)); Harada, M. (Nagoya Univ. (Japan). Dept. of Physics) & Sanda, A.I. (Superconducting Super Collider Lab., Dallas, TX (United States) Rockefeller Univ., New York, NY (United States). Dept. of Physics)

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Constraints on general SU(2)/sub L/ x SU(2)/sub R/ x U(1) electroweak models from nuclear beta decay

The implications of beta-decay experiments for more general versions of SU(2)/sub L/ x SU(2)/sub R/ x U(1) models are analyzed, including the most general one which allows for CP-violation, unequal left- and right-handed quark mixing angles, and mixing in the leptonic sector. For each scenario, the constraints on the pertinent parameters from beta-decay measurements are compared with the constraints provided on them by other data.

Date: January 1, 1986

Creator: Herczeg, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Resonant enhancement of flavor-changing neutrino interactions

The resonant amplification of neutrino oscillations in the presence of flavor-changing neutrino interactions with matter is analyzed. It is shown that a significant {mu}-flavor conversion can take place even in the absence of neutrino mixing in vacuum. To account for the solar neutrino deficit, the strength of the new interactions should be {approximately} 10{sup {minus}2}G{sub F} and the resulting neutrino suppression and spectrum is similar to that in the ordinary MSW effect. I discuss some e… more

Date: October 1, 1991

Creator: Roulet, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Physics at the Z/sup 0/

With the next generation of electron-positron colliders on the immediate horizon, we review the standard model and the precision tests of it which can be carried out at the Z/sup 0/ peak. Emphasis is put on the possibilities for discovering new physics, from additional quarks and leptons to extra neutral gauge bosons. 33 refs., 9 figs.

Date: June 1, 1986

Creator: Gilman, Frederick J.

Item Type: Article

Partner: UNT Libraries Government Documents Department