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in subjects: "Mass Spectra"

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Recent results on open and hidden charm production in e/sup +/e/sup -/ annihilation at 29 GeV

Inclusive )psi) production in e/sup +/e/sup )minus/) annihilation at 29 GeV has been measured with the Mark II detector. The )psi) cross section is found to be 1.1 )+-) 0.5 )+-) 0.4 pb. An upper limit of 0.02 sigma/sub ..mu mu../ is obtained for other sources of )psi) production. )eta) production has also been investigated, using the ..gamma gamma.. decay mode. The )eta) fragmentation function has been measured and found to be in good agreement with the Lund model prediction. )eta)' production … more

Date: March 1, 1988

Creator: Wormser, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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J/. psi. and. Upsilon. production at CDF

Characteristics of J/{psi} and {Upsilon} produced at the Tevatron and detected in the dimuon channel at CDF are reviewed. The masses of the J/{psi} and {Upsilon} are measured to be 3.096 {plus minus} 0.001 GeV/c{sup 2} and 9.469 {plus minus} 0.010 GeV/c{sup 2} respectively. These mass measurements are used to determine the systematic uncertainty on the momentum scale in the central tracking chamber. 2 refs., 14 figs.

Date: January 1, 1990

Creator: Liss, T. (Illinois Univ., Urbana, IL (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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B-physics at CDF and prospects for the next run

Current CDF b-physics results are presented. The analysis is based on data corresponding to an integrated luminosity of 4.4 pb{sup {minus}1} recorded with the CDF detector in 88--89 at the Fermilab Tevatron p{bar p} collider ({radical}{bar s} = 1.8 TeV). Preliminary results include the differential cross section {sub dPt}/{sup d{sigma}(b)}, some reconstructed exclusive B-decays, a limit for the rare decay B{sup 0} {yields} {mu}{sup +} {mu}{sup {minus}} and a measurement of B{bar B}-mixing param… more

Date: September 1, 1991

Creator: Wenzel, H. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Hunt for the 1/sup 1/P/sub 1/ bound state of charmonium

Using the Crystal Ball detector at SPEAR, we have looked for evidence of the isospin-violating decay psi' ..-->.. ..pi../sup 01/P/sub 1/, where /sup 1/P/sub 1/ is the predicted spin-singlet p-wave bound state of charmonium. For a /sup 1/P/sub 1/ state at the predicted mass (approx. 3520 MeV), we obtain the 95% confidence level limits: BR(psi' ..-->.. ..pi../sup 01/P/sub 1/) < 0.55%, BR(psi' ..-->.. ..pi../sup 01/P/sub 1/)BR(/sup 1/P/sub 1/ ..-->.. ..gamma..n/sub c/ < 0.14%. These limits are com… more

Date: February 1, 1982

Creator: Porter, Frank C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Q sup 2 and A dependence of. Delta. (1232) electroexcitation in nuclei

Inclusive electron scattering measurements from SLAC of {Delta} electroexcitation in nuclei are presented. Electrons with energies of 0.96, 1.1, 1.3 and 1.5 GeV were scattered from H, {sup 4}He, C, Fe and W at 37.5{degree} and detected with the End Station A 1.6 GeV/c spectrometer. Q{sup 2} at the {Delta} peak ranged from 0.2 to 0.5 (GeV/c{sup 2}). For all nuclear targets the {Delta} peak position shifts for higher invariant mass as Q{sup 2} increases and in all but one case is above that of th… more

Date: January 1, 1989

Creator: Sealock, R.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Study of four-lepton final states in electron-positron interactions at 29 GeV

This thesis presents a study of electron-positron scattering to four light leptons. The motivations behind it are twofold. Firstly, the study is a test of the theory of electron-positron interactions to 4th order in the fine structure constant {alpha}. A deviation from the theory could indicate the existence of a heavy new particle. Secondly, a measurement of these processes may prove useful in the understanding of other QED-type reactions. The method for simulating the four-lepton processes by… more

Date: August 1, 1989

Creator: Petradza, A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Production of the f sub 0 (975) meson in J/. Psi. decays

Preliminary results on the production and decay of the f{sub 0}(975) meson in the processes J/{Psi} {yields} {phi}{pi}{sup +}{pi}{sup -}, J/{Psi} {yields} {phi}{pi}{sup 0}{pi}{sup 0}, J/{Psi} {yields} {phi}K{sup +}K{sup -}, and J/{Psi} {yields} {omega}{pi}{sup +}{pi}{sup -} are reported on. The data sample, corresponding to 5.8 {times} 10{sup 6} produced J/{Psi}'s, were collected with the MARK-III detector at SPEAR. In a coupled- channel fit to the invariant mass distribution of the {pi}{sup +}… more

Date: November 1, 1989

Creator: Lockman, W.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Pion production in heavy ion reactions near absolute thresholds

Pion production in heavy ion collisions at energies below the free nucleon-nucleon threshold, i.e., at energies, where the pion mass exceeds the kinetic energy of a projectile nucleon in the zero momentum frame, has been discussed for a long time in terms of probing the intrinsic Fermi motion in the projectile and target nuclei. However, as the beam energy is lowered, this process gets more and more unlikely and below a certain energy it should not be observed anymore. In a sharp cut-off Fermi … more

Date: January 1, 1984

Creator: Stachel, J.; Braun-Munzinger, P.; Paul, P.; Zhang, P. H.; Obenshain, F. E.; Plasil, F. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

J/psi results from Mark III

Results from the Mark III collaboration on related hadronic and radiative decays of the J/psi are presented. From a data sample of 5.8 million produced J/psi decays disintegrations into either ..gamma.., ..omega.., or phi plus K anti K, K anti K..pi.., eta..pi pi.. or ..pi pi.. are studied. These results are valuable in the understanding of the nature and composition of the 2/sup + +/theta(1720) and the 0/sup - +/iota(1440), the primary candidates for gluonic matter.

Date: July 1, 1986

Creator: Stockhausen, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Charge exchange photoproduction and the a sub 1 (1260)

Although recent analyses of {tau}-lepton decay and a reanalysis of hadron production data gave consistent results for the mass of the a{sub 1}({approximately}1250 MeV), other results, both experimental and theoretical, have suggested a significantly smaller value for this parameter. The purpose of this talk is to present our data on the charge-exchange photoproduction reaction, {gamma}{rho} {yields} {Delta}{sup ++}{pi}{sup +}{pi}{sup {minus}}{pi}{sup {minus}}. Our data derive from a hydrogen bu… more

Date: January 1, 1991

Creator: Condo, G. T.; Handler, T. & Blackett, G. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Two gauge boson physics at future colliders

Electroweak unification suggests that there should be WW and ZZ physics analogous to {gamma}{gamma} physics. Indeed, WW and ZZ collisions will provide an opportunity to search for the Higgs boson at future high energy colliders. Cross sections in the picobarn range are predicted for Higgs boson production at the proposed 40-TeV SSC. While other states may be produced by WW and ZZ collisions, it is the Higgs boson that looms as the most attractive objective. 31 refs., 5 figs.

Date: May 13, 1988

Creator: Cahn, Robert N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Multiple-neutral-meson decays of the /tau/ lepton and electromagnetic calorimeter requirements at Tau-Charm Factory

This is a study of the physics sensitivity to the multiple-neutral-meson decays of the /tau/ lepton at the Tau-Charm Factory. The sensitivity is compared for a moderate and an ultimate electromagnetic calorimeter. With the high luminosity of the Tau- Charm Factory, a very large sample of the decays /tau//sup /minus// /yields/ /pi//sup /minus//2/pi//sup 0//nu//sub /tau// and /tau//sup /minus// /yields/ /pi//sup /minus//3/pi//sup 0//nu//sub /tau// can be collected with both detectors. However, wi… more

Date: August 1, 1989

Creator: Gan, K.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Hadron production in e/sup +/e/sup -/ annihilation at 29 GeV

Recent results from HRS on the production of scalar, tensor, and charm mesons and of strange and charm baryons in e/sup +/e/sup -/ annihilation are presented. The production of f/sub 0/(975), f/sub 2/(1270), and K/sub 2/*(1430) is shown briefly. The decays of D*(2010)/sup +/ and D*(2007)/sup 0/ are studied in detail. The production of ..xi../sup -/ and ..sigma..(1385)/sup + -/ is mentioned. Finally, the preliminary analyses of ..lambda../sub c/ and ..sigma../sub c//sup 0,++/ productions are pre… more

Date: January 1, 1987

Creator: Sugano, K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent results from the CDF (Collider Detector at Fermilab) experiment at the Tevatron proton-antiproton collider

Recent results from the CDF experiment are described. The Standard Model gives a good description of jet production, and W/Z production and decay. There is no evidence yet for the top quark, for fourth generation quarks, or for deviations from the Standard Model ascribable to quark substructure, supersymmetric particles, or heavy additional W-like or Z-like bosons. Limits are given where applicable. A search for a light Higgs Boson is also described. 11 refs., 24 figs.

Date: September 1, 1989

Creator: Geer, S. (Harvard Univ., Cambridge, MA (USA). High Energy Physics Lab.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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QCD and jets at CDF

A summary of QCD results from the Collider Detector at Fermilab is presented. Comparisons are made to leading order, O({alpha}{sub s}{sup 2}), and next-to-leading order, O({alpha}{sub s}{sup 3}), parton level calculations and to leading logarithm shower Monte Carlo results.

Date: January 1, 1992

Creator: Flaugher, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent. Psi. prime results from Mark III

Results on {Psi}{prime} decays from Mark III are presented. With a data sample of 240,000 {psi}{prime} events, we measure {psi}{prime} {yields} {pi}{sup +}{pi}{sup {minus}}{psi}, {psi}{prime} {yields} {eta}{psi}, {psi}{prime} {yields} {gamma}{chi}{sub c}, {psi}{prime} {yields} {gamma}4{pi}{sup {plus minus}}, {psi}{prime} {yields} {gamma}6{pi}{sup {plus minus}}, and perform a search for {psi}{prime} {yields} {rho}{pi}. Implications of our measurements are discussed. 14 refs., 6 figs., 1 tab.

Date: October 1, 1989

Creator: Mir, R. (Washington Univ., Seattle, WA (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High intensity 5 eV cw laser substained O-atom exposure facility for material degradation studies

An atomic oxygen exposure facility has been developed for studies of material degradation. The goal of these studies is to provide design criteria and information for the manufacture of long life (20 to 30 years) construction material for use in low earth orbit. The studies that are being undertaken using the facility will provide (1) absolute reaction cross sections for use in engineering design problems, (2) formulations of reaction mechanisms for use in selection of suitable existing materia… more

Date: January 1, 1986

Creator: Cross, J. B.; Spangler, L. H.; Hoffbauer, M. A. & Archuleta, F. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Stack contamination effects during small-scale combustion testing of synthetic fuels

The Analytical Chemistry Branch at the Pittsburgh Energy Technology Center has undertaken the assessment of the possible environmental impact of substituting synfuels for petroleum-based fuels in utility and industrial boilers. The assessment is based on a study of results obtained from the analysis of trace organic compounds present in the exaust gases of a fully instrumented 20-hp firetube boiler. The stack gases from petroleum-based fuels, synfuels, and methanol combustion tests have been sa… more

Date: January 1, 1984

Creator: Douglas, L.J.; Gibbon, G.A. & White, C.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Photon stimulated desorption of neutral species from aluminum

Photon Simulated Desorption of neutral species (PSD) is the major dynamic gas load in electron synchrotron light source. In the National Synchrotron Light Source, PSD presented initial machine commissioning difficulty. Sensitivity to surface contamination on PSD had been experienced during an incident of Fomblin Oil contamination. U10B-Photon Stimulated Desorption Experimental Station is constructed to investigate: (1) the degree of the contribution to the photon stimulated desorption (PSD) fro… more

Date: January 1, 1991

Creator: Chou, T.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Ultrarelativistic nucleus-nucleus collisions at CERN

The aim of the NA-35 experiment is to study nuclear matter under extreme conditions. Evidence that conditions reached in 60 GeV/N and 200 GeV/N relativistic heavy ion collisions are adequate for the formation of a quark-gluon plasma where color would no longer be confined to hadronic dimensions is presented. Future plans for experiments in 1990--1991 with {sup 32}S beams and 1993 and up with Pb beams at the SPS are discussed. 26 refs., 23 figs., 3 tabs.

Date: October 1, 1989

Creator: Odyniec, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Latest results on the direct CP violation measurements:. Epsilon. prime /. epsilon

Preliminary results, based on the full data sample from Fermilab-E731 and the combined data sample from CERN-NA31, on the direct'' CP-violation measurements {epsilon}{prime}{epsilon} in neutral kaon decay have been reviewed. The E731's results if Re({epsilon}{prime}{epsilon}) = (6.0 {plus minus} 5.8(stat) {plus minus} 3.2(syst) {plus minus} 1.8(MC)) {times} 10{sup {minus}4}, which provides no evidence for direct'' CP-violation, thus supporting the Superweak model; while the NA31's combined resu… more

Date: March 1, 1992

Creator: Hsiung, Yee B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for narrow states produced in the reaction. pi. /sup -/p. -->. n + neutrals at 13 GeV/c

A double-arm lead-glass, lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..-->.. ..gamma gamma..n, ..pi../sup -/p ..-->.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..-->.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. We find a 90% c.1. upper limit sigma.BR < 260 pb for ..gamma gamma.. states with masses from 2.2 to 4.0 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma.… more

Date: January 1, 1980

Creator: Chiang, I. H.; Johnson, R. A. & Kwan, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutral Transverse Momentum Spectra in 60 and 200 A-GeV 16/O + Nucleus and Proton + Nucleus Reactions

Transverse momentum (p/sub tau/) distributions of inclusive photons and neutral pions at midrapidity are measured with a lead glass calorimeter in 60 and 200 A)centerreverse arrowdot)GeV /sup 16/O + nucleus and proton + nucleus reactions. Inclusive photon distributions are compared for central and peripheral reactions. The degree of centrality is determined either from the charged particle multiplicity or from the remaining projectile energy in th forward direction. Deviations from a nucleus+nu… more

Date: January 1, 1987

Creator: Loehner, H.; Albrecht, R.; Awes, T. C.; Baktash, C.; Beckmann, P.; Berger, F. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fragmentation of quarks and gluons, tests of QCD in e/sup +/e/sup -/ annihilation

This report covers the topics of fragmentation of quarks and gluons and tests of QCD in e/sup +/e/sup -/ annihilation and is a summary of a rapporteur talk given at the 1983 International Symposium on Lepton and Photon Interactions at High Energies. New data on the general characteristics of the e/sup +/e/sup -/ environment at the UPSILON and at PETRA and PEP are discussed. For the first time there is a lot of data on resonance production - eta, K*, rho, phi, ..xi... There is more data on c qua… more

Date: October 1, 1983

Creator: Dorfan, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department