Tests of the Standard Model: W mass and WWZ Couplings

Recent tests of the electroweak Standard Model are reviewed, covering the precise measurements of Z decays at LEP I and SLC and measurements of fermion pair production at higher energies at LEP II. Special emphasis is given to new results on W physics from LEP and FNAL

The heavy baryons in the nonperturbative string approach

We present some piloting calculations of the short-range correlation coefficients for the light and heavy baryons and masses of the doubly heavy baryons $\Xi_{QQ'}$ and $\Omega_{QQ'}$ ($Q,Q'=c,b$) in the framework of the simple approximation within the nonperturbative QCD approach.Comment: 21 pages; to appear in Phys. Atom. Nuc

Measurement of the Polarization in the Decays →/⁢*0 and →/⁢

This Letter reports on measurements of the longitudinal polarization fractions in the decays Bd→J/ψK*0 and Bs→J/ψφ using data collected with the Collider Detector at Fermilab. Bd mesons are reconstructed through the decay chain Bd→J/ψK*0, J/ψ→μ+μ−, K*0→K+π−. A sample of 65±10Bd events is used to obtain a longitudinal polarization fraction of γL/γ=0.65±0.10(stat)±0.04(syst). Bs mesons are reconstructed through the decay chain Bs→J/ψφ, J/ψ→μ+μ−, φ→K+K−. A sample of 19±5Bs events is used to obtain the result γL/γ=0.56±0.21(stat)−0.04+0.02(syst)

Jet pseudorapidity distribution in direct photon events in ⁢¯ collisions at √ =1.8⁢TeV

We present the first measurement of the jet pseudorapidity distribution in direct photon events from a sample of pp¯ collisions at s=1.8TeV, recorded with the Collider Detector at Fermilab. Quantum chromodynamics (QCD) predicts that these events are primarily from hard quark-gluon Compton scattering, qg→qγ, with the final state quark producing the jet of hadrons. The jet pseudorapidity distribution in this model is sensitive to parton momentum fractions between 0.015 and 0.15. We find that the shape of the measured pseudorapidity distribution agrees well with next-to-leading order QCD calculations

Reconstruction of ⁰ →/⁢⁰ and Measurement of Ratios of Branching Ratios Involving →/⁢* and ⁺ →/⁢⁺

We report on the reconstruction of the decay mode B0→J/ψKS0 using 19.3pb−1 of data collected by the Collider Detector at Fermilab in p¯p collisions at s=1.8TeV. A signal of 41.8±6.9 events, with a signal-to-background ratio of 9:1, is observed. Three additional decay modes B+→J/ψK+, B0→J/ψK*(892)0, and B+→J/ψK*(892)+ are reconstructed. We measure three ratios of branching ratios, each one relative to the B+→J/ψK+ mode. We also report the ratio of decay rates, γ(B→J/ψK*)/γ(B→J/ψK), for the vector-vector relative to the vector-pseudoscalar modes, to be 1.32±0.23(stat)±0.16(syst)

A Search for second generation leptoquarks in <i>p¯p</i> bar collisions at √ = 1.8 TeV

We present the results of a search for second generation leptoquarks S2 using 19.3pb−1 of data collected at the Collider Detector at Fermilab (CDF) in pp¯ collisions at s=1.8 TeV during the 1992–93 collider run. We have searched for S2S2¯ pairs assuming that each leptoquark decays to a muon + quark with a branching ratio β. We find two candidate events, consistent with an expected background of 1.11±0.48. We obtain upper limits on σ(pp¯→S2S2¯)β2 as a function of MS2. Using a Monte Carlo prediction for S2S2¯ pair production, we exclude MS2&lt;131GeV/c2 for β=1 and MS2&lt;96GeV/c2 for β=0.5 at 95% C.L

Measurement of the Top Quark Mass in pp‾p\overline pCollisions at s\sqrt s= 1.96 TeV using the Decay Length Technique

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Search for ZZ and ZW production in p¯p collisions at √s = 1.96 TeV

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