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Abstract:

This paper presents the first direct measurement of the B meson differential cross section dσ/dpT in pp̄ collisions at s=1.8 TeV using a sample of 19.3±0.7 pb-1 accumulated by the Collider Detector at Fermilab. The cross section is measured in the central rapidity region |y|<1 for pTB>6.0 GeV /c by fully reconstructing the B meson decays B+→J/ψK+ and B0→J/ψK*0892, where J/ψ→μ+μ- and K*0→K+π-. A comparison is made to the theoretical QCD prediction calculated at next-to-leading order. © 1995 The American Physical Society.

Abstract:

The lifetime of the Bs meson is measured using the semileptonic decay Bs→Ds-+νX. The data sample consists of 19.3 pb-1 of pp̄ collisions at s=1.8 TeV collected by the Collider Detector at Fermilab during 1992-1993. There are 76±8 +Ds- signal events where the Ds is identified via the decay Ds-→φπ-, φ→K+K-. Using these events, the Bs meson lifetime is determined to be τs=1.42-0.23+0.27(stat)±0.11(syst) ps. A measurement of the Bs lifetime in a low statistics sample of exclusive Bs→J/ψ φ decays is also presented in this paper. © 1995 The American Physical Society.

Abstract:

We present a measurement of the mass of the W boson using data collected with the Collider Detector at Fermilab during the 1992-93 collider run at the Fermilab Tevatron. A fit to the transverse mass spectrum of a sample of 3268 W→μν events recorded in an integrated luminosity of 19.7 pb-1 gives a mass MWμ=80.310±0.205(stat)±0.130(syst) GeV/c2. A fit to 5718 W→eν events recorded in 18.2 pb-1 gives MWe=80.490±0.145(stat) ±0.175syst GeV/c2. Combining these results, accounting for correlated uncertainties, yields MW=80.410±0.180 GeV/c2. © 1995 The American Physical Society.

Abstract:

We establish the existence of the top quark using a 67 pb-1 data sample of p̄p collisions at s=1.8 TeV collected with the Collider Detector at Fermilab (CDF). Employing techniques similar to those we previously published, we observe a signal consistent with tt̄ decay to WWbb̄, but inconsistent with the background prediction by 4.8σ. Additional evidence for the top quark is provided by a peak in the reconstructed mass distribution. We measure the top quark mass to be 176±8(stat)±10(syst) GeV/c2, and the tt̄ production cross section to be 6.8-2.4+3.6 pb. © 1995 The American Physical Society.

Abstract:

The properties of two-, three-, four-, five-, and six-jet events with multijet masses >600 GeV /c2 are compared with QCD predictions. The shapes of the multijet-mass and leading-jet-angular distributions are approximately independent of jet multiplicity and are well described by the NJETS matrix element calculation and the HERWIG parton shower Monte Carlo predictions. The observed jet transverse momentum distributions for three- and four-jet events discriminate between the matrix element and parton shower predictions, the data favoring the matrix element calculation. © 1995 The American Physical Society.