The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four collaborations are statistically combined and examined for their consistency with the background hypothesis and with a possible Higgs boson signal. The combined LEP data show no significant excess of events which would indicate the production of Higgs bosons. The search results are used to set upper bounds on the cross-sections of various Higgs-like event topologies. The results are interpreted within the MSSM in a number of "benchmark" models, including CP-conserving and CP-violating scenarios. These interpretations lead in all cases to large exclusions in the MSSM parameter space. Absolute limits are set on the parameter tan β and, in some scenarios, on the masses of neutral Higgs bosons.

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We report the first measurements of inclusive W and Z boson cross sections times the corresponding leptonic branching ratios for pp collisions at √ s = 1.96 TeV based on the decays of the W and Z bosons into electrons and muons. The data were recorded with the CDF II detector at the Fermilab 4Tevatron and correspond to an integrated luminosity of 72.0 ± 4.3 pb −1 . We test e-µ lepton universality in W decays by measuring the ratio of the W → µν to W → eν cross sections and determine a value of 0.991 ± 0.004(stat.) ± 0.011(syst.) for the ratio of W −ℓ−ν couplings (gµ/ge). Since there is no sign of non-universality, we combine our cross section measurements in the different lepton decay modes and obtain σW ×Br(pp → W → ℓν) = 2.749 ± 0.010(stat.) ± 0.053(syst.) ± 0.165(lum.) nb and σ γ * /Z × Br(pp → γ * /Z → ℓℓ) = 254.9 ± 3.3(stat.) ± 4.6(syst.) ± 15.2(lum.) pb for dilepton pairs in the mass range between 66 GeV/c 2 and 116 GeV/c 2 . We compute the ratio R of the W → ℓν to Z → ℓℓ cross sections taking all correlations among channels into account and obtain R = 10.84 ± 0.15(stat.) ± 0.14(syst.) including a correction for the virtual photon exchange component in our measured γ * /Z → ℓℓ cross section. Based on the measured value of R, we extract values for the W leptonic branching ratio, Br(W → ℓν) = 0.1082 ± 0.0022; the total width of the W boson, Γ(W ) = 2092 ± 42 MeV; and the ratio of W and Z boson total widths, Γ(W )/Γ(Z) = 0.838 ± 0.017. In addition, we use our extracted value of Γ(W ) whose value depends on various electroweak parameters and certain CKM matrix elements to constrain the Vcs CKM matrix element, |Vcs| = 0.976± 0.030.

We report the observation of a narrow state decaying into J/psipi+pi- and produced in 220 pb(-1) of p p-bar collisions at =1.96 Tesqaure root of sV in the CDF II experiment. We observe 730+/-90 decays. The mass is measured to be 3871.3+/-0.7(stat)+/-0.4(syst) MeV/c2, with an observed width consistent with the detector resolution. This is in agreement with the recent observation by the Belle Collaboration of the X(3872) meson.

We present a new measurement of the inclusive and differential production cross sections of J= mesons and b hadrons in proton-antiproton collisions at s p 1960 GeV. The data correspond to an integrated luminosity of 39:7 pb ÿ1 collected by the CDF run II detector. We find the integrated cross section for inclusive J= production for all transverse momenta from 0 to 20 GeV=c in the rapidity range jyj < 0:6 to be 4:08 0:02stat 0:36 ÿ0:33 syst b. We separate the fraction of J= events from the decay of the long-lived b hadrons using the lifetime distribution in all events with p T J= > 1:25 GeV=c. We find the total cross section for b hadrons, including both hadrons and antihadrons, decaying to J= with transverse momenta greater than 1:25 GeV=c in the rapidity range jyJ= j < 0:6 is 0:330 0:005stat 0:036 ÿ0:033 syst b. Using a Monte Carlo simulation of the decay kinematics of b hadrons to all final states containing a J= , we extract the first measurement of the total single b-hadron cross section down to zero transverse momentum at s p 1960 GeV. We find the total single b-hadron cross section integrated over all transverse momenta for b hadrons in the rapidity range jyj < 0:6 to be 17:6 0:4stat 2:5 ÿ2:3 syst b.