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Electroweak measurements from CDF and D0

Description: This paper highlights results from electroweak measurements recently obtained by the CDF and D0 collaborations in 1.8 TeV p{ovr p} collisions. The W decay width was extracted from the measurement of W/Z cross section times leptonic branching ratios, and in a direct measurement from a fit of the high-mass tail of the transverse mass spectrum of the W system. Various limits on anomalous gauge boson couplings were obtained in studies of W/Z + {gamma} processes, single leptonic WW, WZ production and double leptonic WW production. Values for {sigma}B(W{gamma}{r_arrow}l{nu}{gamma}), {sigma}B(Z{gamma}{r_arrow}l{sup +}l{sup -}{gamma}), and {sigma}(p{ovr p}{r_arrow}WW + X) were measured. CDF also reports on the observation of an asymmetry in photon rapidity distributions as predicted by the Standard Model. 17 refs., 2 figs., 1 tab.
Date: July 1, 1996
Creator: Neuberger, D. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

New particle searches at Tevatron (II)

Description: Various recent results of new particle searches at the Fermilab Tevatron are presented. No evidence is found for supersymmetric particles (chargino, gluino), leptoquark bosons and heavy gauge bosons in {ital p{anti P}} collisions at {radical}s = 1.8 TeV. Excluded mass regions for each particle are determined.
Date: May 1, 1996
Creator: Kamon, T. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Quarkonia production at CDF and D0

Description: In this paper we present results on J/{Psi}, {Psi}(2{ital S}), {chi}{sub c} and {Upsilon} production at {radical}s = 1.8 TeV. These results were obtained from data taken with the CDF and D0 detectors at Fermilab. We cover recently completed analyses of the 1992-1995 collider run. Prospects for the near future are also discussed.
Date: June 1, 1996
Creator: Papadimitriou, V. & Collaborations, CDF and D0
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

Probing pomeron structure at Fermilab

Description: Using the CDF detector, dijet and W production with rapidity gaps has been searched for as evidence for hard-pomeron induced diffraction. Diffractive W`s are sensitive to a pomeron with a hard-quark structure, while diffractive dijets are sensitive to both hard-gluon and hard-quark structure. No evidence of diffractive W`s has been found down to the few percent level and the fraction of diffractive dijets is measured to be ({minus}0.03 {plus_minus} 0.37)%, or consistent with zero. The existence of colorless exchange between jets has been confirmed. Both the DO and CDF detectors show a statistically significant excess of dijet events with rapidity gaps between the jets at the level of 1-2% of all dijets.
Date: May 1, 1995
Creator: Melese, P. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Recent results on QCD at the Tevatron (CDF and D0)

Description: In the last run the Tevatron collider delivered an integrated luminosity of 29.9 pb{sup {minus}1} to CDF and D0. We describe here some preliminary result from analyses of relevant QCD processes in the 1992--1993 data from the two experiments.
Date: November 1, 1993
Creator: Meschi, E. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Quarkonium production in proton antiproton collisions at the Tevatron

Description: Charmonium and bottomonium production is studied using {mu}{sup +}{mu}{sup -} data samples collected by the CDF and D{null} experiments during the 1992-96 {ital p{anti p}} collider run at the Fermilab Tevatron. The inclusive cross sections as a function of the transverse momentum of reconstructed quarkonium states are measured. The results are compared with theoretical predictions, which take into account different quarkonium production mechanisms.
Date: November 1, 1996
Creator: Tkaczyk, S.M. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Diboson production at the Tevatron

Description: The CDF and D{null} detectors at the Tevatron Collider are being used to measure {ital WW}, {ital WZ}, and {ital ZZ} production as well as {ital W}{sub {gamma}} and {ital Z}{sub {gamma}} production in order to study Trilinear Gauge Couplings. Improved limits on nonstandard coupling parameters are given and prospects for further improvement are discussed.
Date: September 1, 1996
Creator: Nodulman, L.J. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Heavy flavour physics from top to bottom

Description: We review the status of heavy flavour physics at the Fermilab Tevatron collider by summarizing recent top quark and B physics results from CDF and D0. In particular we discuss the measurement of the top quark mass and top production cross section as well as B meson lifetimes and time dependent B{bar B} mixing results. An outlook of perspectives for top and B physics in Run II starting in 1999 is also given. 38 refs., 23 figs., 8 tabs.
Date: January 1, 1997
Creator: Paulini, M. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Production of Gauge Bosons at the Tevatron

Description: The CDF and D0 collaborations have used recent data taken at the Tevatron to perform QCD tests with W and Z bosons decaying leptonically. D0 measures the production cross section times branching ratio for W and Z bosons and determines the branching ratio B(W {yields} l{nu}) = (10.43 {+-} 0.44)% (l = e, {mu}). This also gives an indirect measurement of the total width of the W boson: {Gamma}{sub W} = 2.16 {+-} 0.09 GeV. The W cross section times branching ratio into tau leptons is measured to be {sigma}({anti p}p {yields} W + X)B(W {yields} {tau}{nu}) = 2.38{+-}0.13 nb, from which the ratio of the coupling constants is determined: g{sub {tau}}{sup W}/g{sub e}{sup W} = 1.004 {+-} 0.019 {+-} 0.026. D0`s measurement of the differential d{sigma}/dP{sub T} distribution for the Z boson decaying to electrons, discriminates between different phenomenologic vector boson production models. CDF measures the cross section for the Drell-Yan continuum, and extracts improved limits on compositeness scales for quarks and leptons of {Lambda}{sub ql} {approximately} 3 - 6 TeV, depending on the model. Studies of W + Jet production at CDF and D0 find that the QCD prediction underestimates the production rate of W + 1 Jet events by about a factor of 2 as measured by both collaborations.
Date: June 1, 1997
Creator: Gerber, C.E. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Jet Production at the Tevatron

Description: Inclusive jet cross section and dijet angular distribution results from the CDF and D0 collaborations are presented. The possibility that compositeness might be evident at high transverse energies is explored by both experiments. Using the angular distributions, the CDF analysis excludes at the 95% CL regions with {Lambda}{sup +} < 1.8 TeV and {Lambda}{sup -} < 1.6 TeV for a model where all quarks are allowed to be composite objects. The D0 preliminary result excludes at the 95% CL regions with {Lambda}{sup +} < 2.0 TeV for the same model.
Date: June 1, 1997
Creator: Nang, F. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Top Quark Mass Measurements from the Tevatron

Description: We review the measurements of the top quark mass by the CDF and D0 collaborations using Run I data in excess of 1.00 pb{sup -1}. The D0 collaboration has recently updated its measurement of the top quark mass in the lepton + jets channel. The world average of the top quark mass from the CDF and D0 measurements in the lepton + jets channel now stands at 175.6 {+-} 5.5 GeV/c{sup 2}.
Date: June 1, 1997
Creator: Raja, R. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

SUSY searches at the Tevatron

Description: Current results of searches for Supersymmetry from the CDF and D0 collaborations are summarized. Analyses include searches in jets and missing E{sub t}, leptons and missing E{sub t}, and searches for charged and neutral Higgs particles. The CDF ee{gamma}{gamma}E {sub t} event and related analyses are presented.
Date: August 1, 1997
Creator: Culbertson, R. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Photons and diphotons from the Tevatron

Description: Photon measurements from the CDF and D0 collaboration are described. The subjects touched on are loosely organized around the fact that they all have some bearing on the structure functions and pQCD. The methodology of collider measurements is briefly reviewed, and the results for single photons, photons plus jets, photons plus charm and diphotons are discussed. Finally there is a very brief indication of what is expected from the Tevatron based experiments in the future.
Date: August 1, 1997
Creator: Blair, R. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Search for supersymmetry at the Tevatron

Description: We discuss is the search for supersymmetry at the Fermilab Tevatron by the D0 and CDF collaborations in p{anti p} collisions at {radical}s = 1.8 TeV. The searches are performed in the jets plus E{sub T}, leptons plus E{sub T}, and photons plus E{sub T} channels. In these channels there is no excess of events over the expected backgrounds.
Date: December 1, 1997
Creator: Flattum, E. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

QCD aspects of W/Z production at the Tevatron

Description: Hadron colliders are providing valuable opportunities for studying the influence of the strong force on electroweak interactions in both the perturbative and non-perturbative regions. At the Fermilab Tevatron, analysis by CDF and D0 of p{anti p} {yields} W/Z + X events at {radical}s = 1.8 TeV have been used to test a variety of leading order and next-to-leading order QCD predictions. Among the many promising benefits are improvements of parton distribution functions at high Q{sup 2} , demonstration of soft gluon radiation patterns which survive hadronization, and tests of perturbative QCD and resummation calculations.
Date: July 1, 1997
Creator: Guglielmo, G. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Tevatron results on gauge boson couplings

Description: Direct measurements of the trilinear gauge boson couplings by the CDF and D0 collaborations at Fermilab are reviewed. Limits on the anomalous couplings were obtained at a 95% CL from four diboson production processes: W{gamma} production with the subsequent W boson decay to e{nu} or {mu}{nu}, WW production with both the W boson decaying to e{nu} or {mu}{nu}, WW/WZ production with one of the gauge bosons decaying leptonically and the other gauge boson decaying to two jets, and Z{gamma} production with the subsequent Z boson decay to ee, {mu}{mu}, or {nu}{nu}. Limits were also obtained by a combined fit to W{gamma}, WW{yields}dileptons and WW/WZ semileptonic data samples.
Date: June 1, 1997
Creator: Yasuda, T. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Rapidity gaps and hard diffraction at the Tevatron

Description: Preliminary results on jet production with rapidity gaps in p{anti p} collisions are presented for both D0 and CDF. An excess of events with a forward rapidity gap is observed at both {radical}s=1800 GeV and 630 GeV, consistent with a hard single diffractive process. The first evidence for diffractive W production is presented. A class of events with two forward gaps and central dijets is observed at {radical}s=1800 GeV, a topology that is consistent with hard double pomeron exchange. Kinematic properties of events containing rapidity gaps are measured.
Date: June 1, 1997
Creator: Abbott, B. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department