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J/{psi} and {psi}{prime} production at CDF

Description: This paper presents measurements of the J/{psi} and {psi}{prime} production cross sections in p{ovr p} collisions at {radical}s = 1.8 TeV. The cross sections are measured in the kinematic region P{sub T} {gt} 5 GeV/c, {vert_bar}{eta}{vert_bar} {lt} 0.6 using the dimuon decay channel. The fraction of events from B decays is measured and used to calculate the J/{psi} and {psi}{prime} cross sections from B decay. The fraction of J/{psi} events from {chi}{sub c} decays is also measured and used to calculate the J/{psi} cross section from direct production. 11 refs., 5 figs., 1 tab.
Date: July 1, 1996
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Final performance report to the Department of Energy by Prairie View A & M University High Energy Physics

Description: The High Energy Physics (HEP) group at Prairie View A&M University is a collaboratory with Fermi National Accelerator Laboratory (Fermilab), and the universities listed below. The purpose of this collaboration is to contribute to the understanding of heavy quark hadroproduction. Our efforts began in the early 1980`s at Fermilab with the study of the charmonium states, J/{psi} and {chi}, (DE-FG-86ER-40297) and presently with the continued studies of the charmonium system and direct photon production (Fermilab experiment E705) and new studies on bottom production (Fermilab experiment E771) in the High Intensity Laboratory (Proton-West Area) of Fermilab. The Prairie View group will, as a part of their task, be directly responsible for a major part of the PWC system upgrade by developing the electronics for the readouts of the PWC pad chambers. Six in all, these chambers, are a part of new multilevel triggering scheme and represents a departure from the triggering methodology of the previous trigger processors in earlier experiments. The Prairie View group is also involved with the Bottom Collider Detector (BCD) Collaboration which is proposing to study bottom production at the Fermilab Collider and at the Superconducting Super Collider (SSC).
Date: May 14, 1992
Creator: Judd, D.J.
Partner: UNT Libraries Government Documents Department

Tests of QCD at HERA: determination of the gluon density

Description: An overview is given of the various methods available to the colliding beam experiments at HERA to determine the gluon density of the proton. The article includes a description of fits to the structure function F{sub 2}, of studies of dijet and open charm production in deep inelastic scattering, of elastic and inelastic {psi} photoproduction, and of inclusive diffractive scattering. 13 refs., 8 figs.
Date: December 31, 1996
Creator: Repond, J.
Partner: UNT Libraries Government Documents Department

Branching fractions of B{sup plus} {r_arrow} {Psi}(2S)K{sup plus} and B{sup O} {r_arrow} {Psi}(2S)K{sup {asterisk}0} decays at CDF

Description: This paper describes the observation of the decays B{sup {plus}} {r_arrow} {psi}(2S)K{sup {plus}} and B{sup 0} {r_arrow} {psi}(2S)K{sup {asterisk}}(892){sup 0} in 1.8 TeV p{ovr p} collisions and presents measurements of the branching fractions Br(B{sup {plus}} {r_arrow} {psi}(2S)K{sup {plus}}) and Br(B{sup 0} {r_arrow} {psi}(2S)K{sup {asterisk}}(892){sup 0}) relative to Br(B{sup {plus}} {r_arrow} J/{psi}K{sup {plus}}) and Br(B{sup 0} {r_arrow} J/{psi}K{sup {asterisk}}(892){sup 0}), respectively. The {psi}(2S) mesons are reconstructed in both the {psi}(2S) {r_arrow} {mu}{sup {plus}}{mu}{sup {minus}} and {psi}(2S) {r_arrow} J/{psi}{pi}{sup {plus}}{pi}{sup {minus}} channels. The world average branching fractions for the J/{psi} channels are used to extract the absolute branching fractions Br(B{sup {plus}} {r_arrow} {psi}(2S)K{sup {plus}}) = (6.8{plus_minus}1.0(stat.){plus_minus}1.4(syst.)){times}10{sup {minus}4} and Br(B{sup 0} {r_arrow} {psi}(2S)K{sup {asterisk}}(892){sup 0}) = (9.0{plus_minus}2.1(stat.){plus_minus}2. 0(syst.)){times}10{sup {minus}4}. 9 refs., 13 figs., 8 tabs.
Date: July 1, 1996
Creator: Warburton, A.
Partner: UNT Libraries Government Documents Department

Simulation of heavy ion collisions at {radical}s = 20--200 GeV

Description: A new hadronic cascade code (LUCIFER) is introduced, for simulation of relativistic heavy ion collisions at CERN energies and up to RHIC. It is based on a simple, experimentally and theoretically motivated picture of hh interactions. Final state hadrons are produced by decay of intermediate state clusters, or lumps of excited hadronic matter. These are similar to resonances, but have a continuous mass distribution. Clusters are the objects that re-interact in the cascade. Single diffractive dissociation is used to fix the cluster properties. The model has just two parameters: {tau}{sub d}, the decay time of the clusters, and {tau}{sub f} the formation time of the clusters. Comparison is made with recent CERN data in the Pb + Pb system. The first consistent cascade simulation, of J/{psi} production/suppression is presented. It appears likely that a purely hadronic interpretation can be given to recent CERN data on apparently anomalous J/{psi} suppression in Pb + Pb.
Date: November 1, 1996
Creator: Kahana, D.E. & Kahana, S.H.
Partner: UNT Libraries Government Documents Department

Quarkonia production at D0

Description: We present results on inclusive J/{psi} production in the central and forward regions and {Upsilon} production in the central region using dimuon data collected with the D0 detector during the 1992-1995 Tevatron collider run. Results on inclusive single muon production in the forward region are also given. In general, the QCD predictions for charmonium and bottomonium are incomplete. In charmonium production, prompt J/{psi} production appears not to be dominated by {chi}{sub c} decay. In bottomonium production, the predicted {Upsilon} cross section in underestimated by a factor of five indicating the presence perhaps of yet unseen {chi}{sub b} 3P- or D- wave states. Finally, the inclusive single muon cross section in the forward region is a factor of four above the NLO QCD prediction. This difference is larger than that found in the central region by a factor of two. 12 refs., 6 figs.
Date: August 1, 1996
Creator: Johns, K.A.
Partner: UNT Libraries Government Documents Department

Quarkonia production at CDF

Description: We present the results of J/{psi}, {psi}{prime}, {chi}{sub c} and {Upsilon}(1S), {Upsilon}(2S), {Upsilon}(3S) production in the proton-antiproton collisions at {radical}s = 1800 GeV measured with the CDF Detector. Contributions of different production mechanisms are discussed. 10 refs., 7 figs.
Date: August 1, 1996
Creator: Demina, R.
Partner: UNT Libraries Government Documents Department

The magnitude of the gluon condensate and the masses of c and b quarks from the families of T/{Psi} and {Upsilon} mesons

Description: It is shown that the model used by Shifman, Vainshtein, and Zakharov for the description of the experimental function R{sub c}(s) in the form of a sum of {delta}-functions and the plateau contradicts the Wilson operator expansion (O.E.) in the terms due to the gluon condensate. A QCD model with an infinite number of vector mesons does satisfy the requirements of the O.E. for masses and electronic width resonances close to the experimental values. The region of allowable values of the masses of c- and b-quarks and the gluon condensate compatible with the O.E. is obtained.
Date: November 1, 1993
Creator: Geshkenbein, B. & Morgunov, V.
Partner: UNT Libraries Government Documents Department

Measurements of heavy quark production at D0

Description: We report measurements of the inclusive single muon and b-quark cross sections in p{bar p} collisions at {radical}s = 1.8 TeV using the D0 detector at the Fermilab collider, for the kinematic range {vert_bar}yb{vert_bar} < 1.0 and P{sub t}{sup b} > 6 GeV/c. We also report preliminary measurements on the J/{psi} and {Upsilon} production cross sections.
Date: May 1, 1995
Creator: Markosky, L.
Partner: UNT Libraries Government Documents Department

Quarkonia production at Fermilab

Description: Recent data on J/{psi}, {psi}(2S), {chi}{sub c} and {gamma} production has unraveled unexpected features of Q{bar Q} bound states production in high energy hadronic collisions. In the 1992-1995 runs CDF has collected large samples of J/{psi}, {psi}(2S) and {gamma} identified through their muonic decay. In the charmonium system all production sources have been separately measured and compared with the theoretical predictions. A large excess of direct production has been observed for both {psi}(2S) and J/{psi}. The relative production rate for the {chi}{sub c}{sup 1} and {chi}{sub c}{sup 2} has also been measured. Results on J/{psi}, {psi}(2S) and {chi}{sub c} production from the fixed target experiments E789,E705 and E672/706 are also presented. Important features of the production of charmonium states are shared by fixed target and collider data.
Date: July 1, 1995
Creator: Sansoni, A.
Partner: UNT Libraries Government Documents Department

Experimental studies of elementary particle interactions at high energies. Summary technical progress report

Description: This is a report of the research activities of the Experimental High Energy Physics group of The Rockefeller University. As this is an annual progress report, the emphasis is on last year`s research activities. However, since it is the last of a series of 5 such reports to be submitted to the DOE under the present 5 year contract, an effort has been made to provide comprehensive coverage of the research activities of the group throughout the contract period. In the past 5 years, the research program encompassed three major areas: the UA-6 experiment at CERN, the CDF experiment at Fermilab, and several SSC projects. The UA-6 experiment studies direct-{gamma} and J/{Psi} production in pp and {bar p}p interactions at {radical}s = 22.5 GeV.4. In the CDFF experiment the authors have concentrated in the area of small angle physics, where the objective has been to measure the elastic, diffractive and total cross sections, and to provide an absolute calibration of the machine luminosity. The SSC research projects related to two experiments: The Solenoidal Detector Collaboration and the ``low p{sub T} physics`` experiment.
Date: March 31, 1992
Partner: UNT Libraries Government Documents Department

Support of experimental high energy physics research at the University of South Carolina. Final technical report, 1980--1992

Description: Twelve years of support by the US Department of Energy have turned a two man team with no equipment and no graduate students working on a single experiment into an active group of four professors, one post-doctoral research associate and three graduate students working with appropriate equipment on three major experiments and several other projects. 162 references.
Date: December 31, 1992
Creator: Childers, R.L.; Darden, C.W.; Rosenfeld, C. & Wilson, J.R.
Partner: UNT Libraries Government Documents Department

[Relativistic heavy-ion collisions]; Annual report

Description: This report discusses the following topics: quark-hadron phase transition; hadron production without phase transition; fractal structure in multiparticle production; and j/psi suppression in pA collisions. (LIP)
Date: June 1, 1993
Creator: Hwa, R.C.
Partner: UNT Libraries Government Documents Department

J/{psi} production in p{anti p} collisions at {radical}s = 1.8 TeV

Description: The authors have studied J/{psi} production in p{anti p} collisions at {radical}s = 1.8 TeV with the D0 detector at Fermilab, using a {mu}{sup +}{mu}{sup {minus}} data sample corresponding to an integrated luminosity of 13 pb{sup {minus}1}. They have measured the inclusive J/{psi} production cross section as a function of J/{psi} transverse momentum p{sub T}. For the kinematic range p{sub T} > 8 GeV/c and {vert_bar}{eta}{vert_bar} < 0.6 they obtain Br(J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}) {center_dot} {sigma}(p{anti p} {yields} J/{psi} + X) = 1.93 {+-} 0.16(stat) {+-} 0.43(syst) nb. Using the muon impact parameter they have estimated the fraction of J/{psi} mesons coming from B meson decays to be f{sub b} = 0.35 {+-} 0.09 (stat) {+-} 0.10 (syst) and inferred the inclusive b production cross section. From the information on the event topology a fraction of non-isolated J/{psi} events has been measured to be f{sub non-isol} = 0.64 {+-} 0.09(stat) {+-} 0.06(syst). They have also obtained the fraction of events resulting from radiative decays of {chi}{sub c} states as f{sub {chi}} = 0.30 {+-} 0.07(stat) {+-} 0.07(syst). They discuss the implications of the measurements for charmonium production processes.
Date: July 1, 1995
Creator: Abachi, S.
Partner: UNT Libraries Government Documents Department

Precision measurements of charmonium states formed in {anti p}p annihilation

Description: Fermilab experiment E-760 studies the resonant formation of Charmonium states in proton-antiproton interactions using a hydrogen gas-jet target in the antiproton Accumulator ring at Fermilab. Precision measurements of the mass and width of the Charmonium states, {chi}{sub 1}, {chi}{sub 2} and a new measurement of the {psi} mass are presented.
Date: August 1, 1991
Creator: Armstrong, T.A.; Bettoni, D. & Bharadwaj, V.
Partner: UNT Libraries Government Documents Department

Support of hadroproduction of bottom using the 800 GeV/c primary proton beam at the Fermilab tevatron. Final performance report, June 14, 1988--May 14, 1992

Description: The High Energy Physics (HEP) group at Prairie View A&M University is a collaborator with Fermi National Accelerator Laboratory (Fermilab), and the universities listed below. The purpose of this collaboration is to contribute to the understanding of heavy quark hadroproduction. Our efforts began in the early 1980`s at Fermilab with the study of the charmonium states, J/{psi} and {chi}, (DE-FG-86ER-40297) and presently with the continued studies of the charmonium system and direct photon production (Fermilab experiment E705) and new studies on bottom production (Fermilab experiment E771) in the High Intensity Laboratory (Proton-West Area) of Fermilab. The Prairie View group will, as a part of their task, be directly responsible for a major part of the PWC system upgrade by developing the electronics for the readouts of the PWC pad chambers. Six in all, these chambers, are a part of new multilevel triggering scheme and represents a departure from the triggering methodology of the previous trigger processors in earlier experiments. The Prairie View group is also involved with the Bottom Collider Detector (BCD) Collaboration which is proposing to study bottom production at the Fermilab Collider and at the Superconducting Super Collider (SSC).
Date: May 14, 1992
Creator: Judd, D.J.
Partner: UNT Libraries Government Documents Department

Quarkonia production in p{bar p}-collisions with CDF

Description: The production cross sections for {gamma}`s, {psi}`s and {chi}{sub c}`s in high energy p{bar p} collisions have been measured using the CDF detector at Fermilab. Heavy quarkonia production involves a variety of mechanisms, and the data is used to disentangle various components. Large prompt {psi}-cross sections were observed, contrary to conventional expectations.
Date: July 1, 1995
Creator: Bauer, G.
Partner: UNT Libraries Government Documents Department

Charm and beauty results from CDF and D0

Description: I report, for the CDF and D0 collaborations, results from the 92-93 Tevatron Collider run concerning charm and beauty quark production and beauty meson decay properties.
Date: May 1, 1995
Creator: Derwent, P. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

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

Description: 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 enhancement ..cap alpha.. in the J)psi) and the two photon data and about half the maximum value in the other two data sets. The radius parameter )tau)(an average over space and time) given by pion pair analyses lies within a band of +-0.10 fm around 0.73 fm and is the same, within errors, for all four data sets. Pion triplet analyses also give a consistent radius of approx. 0.54 fm. fits to two-dimensional distributions R(q/sub T//sup 2/, q/sub C//sup 2/) of invariant components of Q/sup 2/ = q/sub T//sup 2/ )plus) q/sub C//sup 2/ give )tau)/sub T/ approx. )tau)C approx. )tau), where q/sub T/ is the transverse three-momentum difference calculated with respect to the net pair three-momentum, and q/sub C/ is in effect the longitudinal three-momentum difference in the pion pair rest frame. When q/sub T/ is calculated with respect to the jet axis for two-jet events in the e/sup )plus/)e/sup )minus/) annihilation data at ..sqrt..s = 29 GeV, a fit to R(q/sub T//sup 2/, q/sub C//sup 2/) also gives )tau)/sub T/ approx. )tau)/sub C/ approx. )tau). Noting that q/sub L/ and q/sub 0/ are not invariant, we make fits to R(/sub T//sup T/, q/sub L//sup 2/) and to R(q/sub T//sup 2/, q/sub 0//sup 2/) (Kopylov formulation), and we find )tau)/sub 0/ approx. )tau)/sub L/ approx. )23))tau)/sub T/ to )12))tau)/sub T/. ...
Date: December 1, 1987
Creator: Juricic, I.
Partner: UNT Libraries Government Documents Department

Nuclear physics studies with medium energy probes

Description: This report discusses the quark-quark interactions involved in charmonium states; experiments with QCD overtones; and nuclear structure experiments. (LSP)
Date: January 1, 1990
Creator: Seth, K.K.
Partner: UNT Libraries Government Documents Department

Resonance production in two-photon interactions

Description: Resonance production in two-photon interactions is studied using data collected with the ASP detector at the PEP e/sup +/e/sup /minus// storage ring located at the Stanford Linear Accelerator Center. The ASP detector is a non-magnetic lead-glass calorimeter constructed from 632 lead-glass bars. It covers 94% of 4..pi.. in solid angle, extending to within 20/degree/ of the beamline. Lead-scintillator calorimeters extend the coverage to within 21 mr of the beamline on both sides. Energy resolution of ..sqrt..E/10%, where E is the energy is GeV, is achieved for electrons and photons in the lead-glass calorimeter, and particle trajectories are reconstructed with high efficiency. A total luminosity of 108 pb/sup /minus/1/ was collected with the ASP detector at a center-of-mass energy of 29 GeV. The observed process is e/sup +/e/sup /minus// ..-->.. e/sup +/e/sup /minus//..gamma..*..gamma..* ..-->.. e/sup +/e/sup /minus//X, is a pseudoscalar resonance (J/sup PC/ = 0/sup /minus/+/) and ..gamma..* is a virtual (mass /ne/ 0) photon. The outgoing electrons scatter down the beampipe and are not detected. The observed resonances are the /eta/ and /eta/' mesons, with masses of 549 and 958 MeV, respectively. They are detected in the ..gamma gamma.. decay mode; a total of 2380 +- 49 /eta/ ..-->.. ..gamma gamma.. and 568 +- 26 /eta/' ..-->.. ..gamma gamma.. events are observed. From the number of events, the detection efficiency, and the calculated production cross sections the radiative widths, GAMMA/sub ..gamma gamma../, of the /eta/ and /eta/' were measured and found to be: GAMMA/sub ..gamma gamma../(/eta/) = .481 +- .010 +- .047keV and GAMMA/sub ..gamma gamma../(/eta/') = 4.71 +- .22 +- .70keV. These results are in good agreement with the world average values. 67 refs., 42 figs., 20 tabs.
Date: February 1, 1989
Creator: Roe, N.A.
Partner: UNT Libraries Government Documents Department

University of Virginia experimental and theoretical high energy physics

Description: This report discusses research being done in high energy physics at the University of Virginia in the following areas: charmonium; B mesons decay; B physics at the SCC; and symmetry and field theory. (LSP)
Date: January 10, 1991
Creator: Cox, B.
Partner: UNT Libraries Government Documents Department

An amplitude analyses of the K K-bar system (M < 2 GeV/C sup 2 ) produced in J/. Psi. radiative decay

Description: Using the 5.8 {times} 10{sup 6} J/{psi} events collected by the MARK 3 experiment on the SPEAR e{sup +}e{sup {minus}} storage ring at SLAC, a mass independent amplitude analysis of the J/{psi} {yields} {gamma} K{sub s}K{sub s} and J/{psi} {yields} K{sup +}K{sup {minus}} decays is presented. For K{bar K} systems having mass less than 2 GeV/c{sup 2}, the efficiency-corrected spherical harmonic moments of the J/{psi} joint decay angular distribution are measured. Fits are then performed in each independent mass interval in order to extract the underlying helicity amplitude structure; amplitudes describing K{bar K} systems of spin zero and spin two are included simultaneously. For the first time, a large spin zero component in the {theta}(1720) mass region is observed; consistent results are obtained for the data samples corresponding to the individual decay modes. This structure is attributed to the production of an S wave resonance, the f{sub 0}(1710), of mass and width M = 1710 {plus minus} 10 MeV/c{sup 2}, {Gamma} = 186 {plus minus} 30 MeV/c{sup 2}, respectively, with branching fraction Bf(J/{psi} {yields} {gamma}f{sub 0}, f{sub 0} {yields} K{bar K}) = (6.47 {plus minus} 1.14 {plus minus} 0.84) {times} 10{sup {minus}4}. A small amount ({approximately}24%) of spin two component in this mass region cannot be ruled out with the present statistics. These results revise the previous conclusion that the {theta}(1720) is a spin two resonance, a result obtained on the basis of spin hypothesis tests, which assumed that either pure spin zero or pure spin two states contribute in this mass region, but not both. The previous measurements of the f{sub 2}{prime} (1525) have been refined in the present analysis because of the simultaneous inclusion of spin zero and spin two amplitudes in the fit.
Date: November 1, 1991
Creator: Chen, Liang-Ping.
Partner: UNT Libraries Government Documents Department