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in subjects: "Leptons"

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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

Search for the neutrinoless muon decay. mu. /sup +/. -->. e/sup +/. gamma

Separate muon, electron, and tau numbers are conserved in the minimal standard model of electroweak interactions with massless neutrinos. However, in many extensions to the standard model, separate lepton numbers are not expected to be conserved quantities. A new search for muon number non-conserving processes has been undertaken at the Los Alamos Meson Physics Facility (LAMPF), specifically to look for three neutrinoless decay modes of the muon. The search for the decay of a muon to an electro… more

Date: July 1, 1985

Creator: Wilson, S.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Di-leptons at the Bevalac

Recent results on the production of di-leptons measured by the Di-Lepton-Spectrometer (DLS) collaboration are discussed. Results are reported from observations made on p /plus/ Be collisions with proton beams from 1.0 to 4.9 GeV and on Ca collisions with calcium beams of 1.0 to 2.0 GeV/A. The shape of the distributions are similar to that at higher energies. The low mass cross section appears to be explained by ..pi..-..pi.. annihilation, but detailed calculations are needed to substantiate tha… more

Date: March 1, 1988

Creator: Matis, H.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Heavy mass states

The indirect evidence for the production of a heavy lepton and direct evidence for the product of a new hadronic state or states in proton-proton interactions is considered for the interpretation requiring the existence of two more leptons and two new quarks. It is shown that such a picture is consistent and in good agreement with existing data. The new structure is located at M = 9.54 GeV/c/sup 2/ and is much wider than the experimental resolution. Also it is asymmetric, suggesting the presenc… more

Date: August 23, 1977

Creator: Paschos, E. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measurement of energy deposited by charged-particle beams in composite targets

We have measured the energy deposited in two types of composite targets by a number of charged-particle beams: targets made of /sup 238/U, Lucite, and polyethylene were exposed to 0.26-GeV protons and 0.33-GeV deuterons, and aluminum-Lucite composites were exposed to 0.5-GeV electrons. In addition, we measured neutrons and gamma rays emitted from solid targets of various materials (including /sup 238/U and iron) exposed to 0.26-GeV protons and 0.33-GeV deuterons. We used passive detectors (ther… more

Date: July 2, 1980

Creator: Farley, E.; Becker, J.; Crase, K.; Howe, R. & Selway, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Light composite fermions: an overview

Some rules which have been proposed, including 't Hooft's anomaly conditions, decoupling conditions and tumbling versus no tumbling are discussed. Then mass generation mechanisms for composite fermions are covered, including weak gauging, strong gauging, and unification. The origin of the different generations of quarks and leptons is then considered. In the context of composite models, the three generations of quarks and leptons must appear in the first approximation as three sets of massless … more

Date: January 1, 1982

Creator: Raby, S.

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

open access

Transverse spin observables in chromodynamics

Quantum Chromodynamics confronts a harsh series of tests in the attempt to formulate a comprehensive approach to the calculation of transverse spin observables. The basic obstacles to understanding transverse spin can be illustrated by considering the transverse structure function g{sub T}(x, Q{sup 2}) = g{sub 1}(x, Q{sup 2}) + g{sub 2}(x, Q{sup 2}), extracted from deep-inelastic scattering using a polarized lepton and a polarized proton. The inadequacy of the transverse-spin basis for quarks a… more

Date: December 1, 1989

Creator: Sivers, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

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

open access

The neutrinos in muon decay

We review the available information on the identity of the neutrino states emitted in muon decay, and discuss the exotic decay {mu}{sup +} {yields} e{sup +} {bar {nu}}{sub e}{nu}{sub {mu}}. 22 refs.

Date: October 21, 1991

Creator: Herczeg, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)

A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.

Date: January 3, 1990

Creator: Gladney, L. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case

The Townsend ionization coefficient in the strong runaway regime is calculated within the framework of the two-term expansion. Results are compared to the 1-D model. General features of the two models are qualitatively similar, but quantitative differences by factors of approx. 2 are observed.

Date: July 15, 1982

Creator: Yu, S. S. & Melendez, R. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analysis of valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/(YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 2/ (Ruby), a study of certain properties of these laser materials related to their valence-electron structures

A direct method of determination of the valence-electron structure from its crystal structure has been presented by the writer at XIIth International Congress of Crystallography, at Ottawa, 1981. Here the method is applied to determine the valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/ (YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ (ruby) to see how certain properties of these laser materials are related to their valence-electron structures. The first point observed is the very stron… more

Date: January 1, 1982

Creator: Yu, S. H. & Yu, L. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

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

open access

Giotto observations of the bow shock at Comet Halley

Preliminary results from the JPA instrument on Giotto indicate that Comet Halley, even on the flanks, has a bow shock which moves backwards and forwards over the spacecraft. To understand the structure properly will require more detailed investigation of the relationships between three particle populations, cometary ions, solar wind ions and electrons.

Date: January 1, 1986

Creator: Formisano, V.; Amata, E.; Wilken, B.; Jockers, K.; Johnstone, A.; Coates, A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Jet rates from deep inelastic muon scattering in the W range of 15 to 35 GeV

Production rates of forward jets in deep inelastic muon scattering are studied using the JADE jet finding algorithm. The evolution of di-jet rates with W is compared to QCD first order predictions in the W range of 15 to 25 GeV. 7 refs., 3 figs.

Date: August 1, 1991

Creator: Salgado, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Proposal to assemble a high resolution-electron sensitive-energy flow calorimeter in the NEULAND spectrometer

A ..gamma.. catcher and a liquid scintillation calorimeter module in a simple configuration that is well suited to the investigation of several different neutrino induced processes are described. The variety of neutrino beams now available at Fermilab and synchrotron intensity and energy together with the high resolution calorimeter allow a multiplicity of experiments to be carried out with a single detector configuration.

Date: January 1, 1977

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Data needs for the track structure of alpha particles and electrons in water

We have made calculations of the ionization spectra for alpha particle and electron tracks in water. We have also computed the number of ions created per micrometre of track length, the energy distribution of the secondaries, and the energy expended per ion pair created. Our aim is less toward theoretical derivations than to obtain a numerically accurate description of the track structure at all energies in a form suitable for biomedical applications. 13 references.

Date: January 1, 1983

Creator: Pagnamenta, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The GALLEX Project

The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of de… more

Date: January 1, 1989

Creator: Kirsten, T. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Strange particle production in neutrino-neon charged current interactions

Neutral strange particle production in charged-current muon-neutrino interactions have been studied in the Fermilab 15-foot neon bubble chamber. Associated production is expected to be the major source of strange particles in charged-current neutrino interactions. sigma-neutral and xi-minus production by neutrinos was observed. The dependence on various leptonic and hadronic variables is investigated. A fit to single and associated production of s, s/anti-s, and c quarks is described based on t… more

Date: January 1, 1986

Creator: Plano, R.; Baker, N. J.; Connolly, P. L.; Kahn, S. A.; Murtagh, M. J.; Palmer, R. B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dose-rate conversion factors for external exposure to photons and electrons

Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sou… more

Date: August 1, 1981

Creator: Kocher, David C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Measurement of B sup 0 -- B sup 0 Mixing Using the MARK II at PEP

B{sup 0}{bar B}{sup 0} mixing has been observed now by several experiments. The signature is the observation of an excess of same-sign dilepton events in datasets containing semileptonic B decays. Several years ago the MARK II published an upper limit on B{sup 0}{bar B}{sup 0} mixing at E{sub cm} = 29 GeV, using data taken at the e{sup +}e{sup {minus}} storage ring PEP. Here we report on the results of a new analysis with increased statistics, using refined methods with better sensitivity and c… more

Date: December 1, 1989

Creator: Porter, F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutrino mixing and oscillation in a grand unified field theory SO(10)

The investigation shows that it is very difficult to achieve neutrino mixing of other than the V/sub ..mu../-..nu../sub tau/ type in any minimal SO(10) model in which neutrino masses are generated by the Gell-Mann-Ramond-Slansky mechanism, because of the severe constraints placed on the mass matrix by quark phenomenology.

Date: January 1, 1980

Creator: Tanaka, K.

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