The results based on 1992–95 data (Run 1) from the CDF and D0 experiments on the measurements of the W boson mass and width are presented, along with the combined results. We report a Tevatron ...collider average MW = 80.456±0.059 GeV. We also report the Tevatron collider average of the directly measured W boson width GammaW = 2.115±0.105 GeV. We describe a new joint analysis of the direct W mass and width measurements. Assuming the validity of the standard model, we combine the directly measured W boson width with the width extracted from the ratio of W and Z boson leptonic partial cross sections. This combined result for the Tevatron is GammaW = 2.135±0.050 GeV. Finally, we use the measurements of the direct total W width and the leptonic branching ratio to extract the leptonic partial width Gamma(W-->enu) = 224±13 MeV.
We report the first observation of dijet events with a double Pomeron exchange topology produced in p collisions at sqrts = 1800 GeV. The events are characterized by a leading antiproton, two jets in ...the central pseudorapidity region, and a large rapidity gap on the outgoing proton side. We present results on jet kinematics and production rates, compare them with corresponding results from single diffractive and inclusive dijet production, and test factorization.
We present results from a measurement of double diffraction dissociation in pp collisions at the Fermilab Tevatron collider. The production cross section for events with a central pseudorapidity gap ...of width Deltaeta(0)>3 (overlapping eta = 0) is found to be 4.43+/-0.02(stat)+/-1.18(syst) mb 3.42+/-0.01(stat)+/-1.09(syst) mb at square root of (s) = 1800630 GeV. Our results are compared with previous measurements and with predictions based on Regge theory and factorization.
We report results from a study of events with a double-Pomeron exchange topology produced in p p collisions at sqrts=1800 GeV. The events are characterized by a leading antiproton and a large ...rapidity gap on the outgoing proton side. We find that the differential production cross section agrees in shape with predictions based on Regge theory and factorization, and that the ratio of double-Pomeron exchange to single diffractive production rates is relatively unsuppressed as compared to the O(10) suppression factor previously measured in single diffractive production.
We report the results of a search for a W' boson produced in pp; collisions at a center-of-mass energy of 1.8 TeV using a 106 pb(-1) data sample recorded by the Collider Detector at Fermilab. We ...observe no significant excess of events above background for a W' boson decaying to a top and bottom quark pair. In a model where this boson would mediate interactions involving a massive right-handed neutrino (nu(R)) and have standard model strength couplings, we use these data to exclude a W' boson with mass between 225 and 536 GeV/c(2) at 95% confidence level for M(W')>>M(nu(R)) and between 225 and 566 GeV/c(2) at 95% confidence level for M(W')<M(nu(R)).
We report a measurement of the fraction of events with a large pseudorapidity gap deltaeta within the pseudorapidity region available to the proton dissociation products X in p+p-->p+X. For a final ...state p of fractional momentum loss xi(p) and 4-momentum transfer squared t(p) within 0.06<xi(p)<0.09 and |t(p)|<1.0 0.2 GeV2 at sqrts=1800 630 GeV, the fraction of events with deltaeta>3 is found to be 0.246+/-0.001 (stat)+/-0.042 (syst) 0.184+/-0.001 (stat)+/-0.043 (syst). Our results are compared with gap fractions measured in minimum bias pp collisions and with theoretical expectations.
We present a new search for H0V production, where H0 is a scalar Higgs boson decaying into bb with branching ratio beta, and V is a Z0 boson decaying into e+e-, mu+mu-, or nunu. This search is then ...combined with previous searches for H0V where V is a W+/- boson or a hadronically decaying Z0. The data sample consists of 106 +/- 4 pb(-1) of pp collisions at square root of s = 1.8 TeV accumulated by the Collider Detector at Fermilab. Observing no evidence of a signal, we set 95% Bayesian credibility level upper limits on sigma(pp --> H0V) x beta. For H0 masses of 90, 110, and 130 GeV/c2, the limits are 7.8, 7.2, and 6.6 pb, respectively.
We report the first largely model independent measurement of charged particle multiplicities in quark and gluon jets, Nq and Ng, produced at the Fermilab Tevatron in pp collisions with a ...center-of-mass energy of 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies of 41 and 53 GeV by counting charged particle tracks in cones with opening angles of theta(c) = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = Ejet theta c varies in the range from 12 to 25 GeV. At Q = 19.2 GeV, the ratio of multiplicities r = Ng/Nq is found to be 1.64+/-0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with resummed perturbative QCD calculations.
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