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in subjects: "Lepton-Lepton Interactions"

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Prospects for physics at e/sup +/e/sup -/ linear colliders

The present thinking on high-energy e/sup /plus//e/sup /minus// linear colliders is reviewed, stressing those points that have consequences for detector design and physics analyses. Detector requirements are discussed. Experimental aspects of the physics that can be done at these colliders are discussed: first the general physics environment, then a standard process, W/sup /plus// W/sup /minus// detection, and finally four examples of the discovery potential of these colliders /emdash/ heavy qu… more

Date: March 1, 1988

Creator: Feldman, G. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The limited streamer tubes system for the SLD warm iron calorimeter

The SLD detector at the Stanford Linear Accelerator Center is a general purpose device for studying e{sup +}{epsilon}{sup {minus}} interaction at the Z{sup 0}. The SLD calorimeter system consists of two parts: a lead Liquid Argon Calorimeter (LAC) with both electromagnetic (22 radiation lengths) and hadronic sections (2.8 absorption lengths) housed inside the coil, and the Warm Ion limited streamer tubes Calorimeter (WIC) outside the coil which uses as radiator the iron of the flux return for t… more

Date: January 1, 1992

Creator: Benvenuti, A. C.; Camanzi, B.; Piemontese, L.; Zucchelli, P.; Calcaterra, A.; De Sangro, R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Total hadron cross section, new particles, and muon electron events in e/sup +/e/sup -/ annihilation at SPEAR

The review of total hadron electroproduction cross sections, the new states, and the muon--electron events includes large amount of information on hadron structure, nine states with width ranging from 10's of keV to many MeV, the principal decay modes and quantum numbers of some of the states, and limits on charm particle production. 13 references. (JFP)

Date: January 1, 1976

Creator: Richter, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Radiative corrections in SU/sub 2/ x U/sub 1/ LEP/SLC

We show the sensitivity of various experimental measurements to one-loop radiative corrections in SU/sub 2/ x U/sub 1/. Models considered are the standard GSW model as well as extensions of it which include extra quarks and leptons, SUSY and certain technicolor models. The observation of longitudinal polarization is a great help in seeing these effects in asymmetries in e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/, tau/sup +/tau/sup -/ on Z/sup 0/ resonance. 25 refs., 22 figs., 10 tabs.

Date: June 1, 1985

Creator: Lynn, B. W.; Peskin, M. E. & Stuart, R. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None]

This thesis describes the results of a search for new leptons with associated heavy neutrinos. The search uses 68.1 pb/sup /minus/1/ of data taken with the TPC2..gamma.. detector at the PEP storage ring. New lepton pairs with charged lepton masses m/sub L/ < 12 GeV and mass differences in the approximate range 0.4 GeV < m/sub L/ /minus/ m/sub/nu/L/ < 2.5 GeV are excluded at the 99% confidence level. Results are also given of a study of search techniques for the region m/sub L/ < 12 GeV, m/sub L… more

Date: May 5, 1988

Creator: Mathis, L. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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(Experimental physics at Yale University: Research proposal and budget Proposal, 1 January 1992--31 December 1996)

This report reviews the following topics: nuclear and quark matter; correlated pairs from heavy ion collisions-search for new low mass resonances coupled to electron-positron collisions; proposed light ion research program; experimental nuclear astrophysics (explosive nucleosynthesis); search for rare decay modes and rare processes in nuclei; and nuclear spectroscopy at the extremes of spin, isospin, and temperature. (LSP).

Date: January 1, 1992

Item Type: Report

Partner: UNT Libraries Government Documents Department

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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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Results on nu/sub. mu. /e Elastic Scattering

A measurement of the nu/sub ..mu../e elastic scattering cross section is presented. These data analyzed were run at the Brookhaven AGS wide band neutrino beam ((E/sub nu/) = 1.5 GeV).

Date: January 1, 1983

Creator: Ahrens, L. A.; Aronson, S. H.; Connolly, P. L.; Callas, J. L.; Cutts, D.; Amako, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Bose-Einstein correlations in e/sup +/e/sup -/ collisions

The MARK II detector is used to study the Bose-Einstein correlation between pairs and triplets of charged pions produced in hadronic decays of the J)psi), the ..sqrt..s = 4 to 7 GeV continuum above the J)psi), two photon events at ..sqrt..s = 29 GeV, and e/sup )plus/)e/sup )minus/) annihilation events at ..sqrt..s = 29 GeV as a function of Q/sup 2/, the four-momentum transfer squared. After corrections for Coulomb effects and pion misidentification, we find a nearly full Bose-Einstein enhanceme… more

Date: December 1, 1987

Creator: Juricic, I.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Measurement of Inclusive Eta Production in e/sup +/e/sup -/ Interactions Near Charm Threshold

The inclusive cross section for eta production in e/sup +/e/sup -/ interactions near charm threshold was measured by use of the Crystal Ball detector at SPEAR. By comparison of the inclusive eta production above and below charm threshold the following limits were obtained: R(e/sup +/e/sup -/ ..-->.. F anti FX)BR(F ..-->.. eta x) < 0.3 (90% C.L., E/sub cm/ < 4.5 GeV); BR(D ..-->.. eta x) < 0.13 (90% C.L., averaged over charged and neutral D components of the psi''). 4 figures, 1 table.

Date: August 1, 1980

Creator: Porter, F. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Lead-Glass Wall addition to the Spear Mark I Magnetic Detector

A ''Lead-Glass Wall,'' consisting of 318 lead-glass Cherenkov shower counters and three wire spark chambers, has been added to one octant of the SPEAR Mark I Magnetic Detector. The wall covers a solid angle of approximately 6 percent of 4..pi.. steradians and has been used to identify and measure the energies of electrons and photons produced in electron-positron collisions. The design, calibration, gain-monitoring, and performance of the system are described.

Date: October 1, 1977

Creator: Feller, J. M.; Barbaro-Galtieri, A. & Dorfan, J. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Study of quark fragmentation in e/sup +/e/sup -/ annihilation at 29 GeV: charged particle multiplicity distributions

This paper presents the charged particle multiplicity distributions for e/sup +/e/sup -/ annihilation at ..sqrt..s = 29 GeV measured in the High Resolution Spectrometer. The data, which correspond to an integrated luminosity of 185 pb/sup -1/, were obtained at the e/sup +/e/sup -/ storage ring PEP. The techniques used to obtain the original distributions from the observed prong numbers are discussed. The multiplicity distribution of the charged particles with a two jet selection has a mean valu… more

Date: January 1, 1985

Creator: Derrick, M.; Kooijman, P.; Loos, J.S.; Musgrave, B.; Price, L.E.; Schlereth, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ratio of D/sup 0/ and D/sup +/ lifetimes from their semileptonic decays

The conventional expectation for the decays of D mesons assumes that the charm quark decays in the presence of light, spectator quarks and thus the lifetimes of both charged and uncharged states are equal. In this article, evidence is presented from DELCO (at SPEAR) that the D lifetimes are quite different for neutral and charged mesons, and the results which have also become available from other experiments are reviewed.

Date: June 1, 1980

Creator: Donaldson, G.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Unusual initial and final state effects in quantum chromodynamics

We have constructed a number of fundamental tests which can be used to probe discrete symmetries, and their possible violations, in the required new physics'' beyond the standard model. On-going experiments with unpolarized e{sup {minus}}e{sup +} collisions contain many events for the production-decay sequence e{sup {minus}}e{sup +} {yields} Z{degrees}, {gamma}* {yields} {tau}{sup {minus}}{tau}{sup +} {yields} (A{sup {minus}X}) (B{sup +}X). From the beam referenced spin-correlation function for… more

Date: December 1, 1991

Creator: Nelson, C.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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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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Panel discussion on laboratory accelerator programs: present and future

The present SLAC accelerator program is summarized briefly, and the future of electron-positron colliders is discussed. Present activities discussed include the PEP storage ring, the SPEAR storage ring, the Linear Accelerator, and the SLAC Linear Collider (SLC) project. Future prospects include a larger scale linear collider. The stability requirements on acceleration are briefly discussed. (LEW)

Date: September 1, 1986

Creator: Richter, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Weak interaction effects in e/sup +/e/sup -/ annihilation with polarised beams

Although the standard gauge model of weak and electromagnetic interactions based on the work of Salam and Weinberg has met with great success, there are experimental facts that will require its extension or its modification to a new gauge model; the discovery of a heavy lepton at SLAC and the absence of parity violation in atoms that is expected from the neutral weak current coupling to electrons are discussed. Three tests are proposed that bear on these questions. First, heavy lepton productio… more

Date: November 2, 1977

Creator: Simard, R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

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

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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

A study of low Q/sup 2/ radiative Bhabha scattering

This thesis presents a study of electron-positron scattering, via nearly real photon exchange, where in the process one or more high energy photons are produced. The motivations behind the work are twofold. Firstly, the study is a sensitive test of the theory of electron-photon interactions, quantum electrodynamics. A deviation from the theory could indicate that the electron is a composite particle. Secondly, a thorough understanding of this process is necessary for experiments to be done in t… more

Date: March 1, 1988

Creator: Karlen, D.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Technical Progress Report of the Indiana University High Energy Physics Group, December 1, 1979-November 30, 1980. [12/1/79-11/30/80]

Research programs during the current contract year are associated with major experiments conducted at SLAC, Fermilab, and CERN. The physics areas under study include an exploration of polarization phenomena in hadron processes, a study of low-p/sub t/ and high-p/sub t/ collisions utilizing the Multiparticle Spectrometer at Fermilab, studies of psi meson production in hadron interactions, and a high-resolution study of e/sup +/e- interactions at high energy at SLAC. The status of the various eff… more

Date: January 1, 1980

Creator: Brabson, B. B.; Crittenden, R. R.; Dzierba, A. R.; Heinz, R. M.; Martin, H. J.; Neal, H. A. et al.

Item Type: Report

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

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Recent Results From DELCO

DELCO is a magnetic spectrometer with Cerenkoc, Time-of-Flight (TOF) and shower counters for particle identification. It is located in IR8 of the PEP storage ring. Data have been obtained at a center of mass energy, ..sqrt..s, of 29 GeV. We report on: (1) the fraction of P, K, ..pi.. in hadronic events; (2) the observation of direct electron signals; and (3) the measurement of D* fragmentation function and its total cross-section. 8 references.

Date: November 1, 1983

Creator: Atwood, W. B.; Baillon, P. H.; Barish, B. C.; Bonneaud, G. R.; DeStaebler, H.; Donaldson, G. J. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Tests of perturbative quantum chromodynamics in photon-photon collisions

The production of hadrons in the collision of two photons via the process e/sup +/e/sup -/ ..-->.. e/sup +/e/sup -/X can provide an ideal laboratory for testing many of the features of the photon's hadronic interactions, especially its short-distance aspects. That part of two-photon physics which is particularly relevant to tests of perturbative QCD is reviewed here. 6 figures.

Date: January 1, 1979

Creator: Brodsky, Stanley J.

Item Type: Article

Partner: UNT Libraries Government Documents Department