We present a search for a Higgs boson decaying to two W bosons in pp collisions at √ s = 1.96TeV center-of-mass energy. The data sample corresponds to an integrated luminosity of 3.0 fb −1 collected with the CDF II detector. We find no evidence for production of a Higgs boson with mass between 110 and 200 GeV/c 2 , and determine upper limits on the production cross section. For the mass of 160 GeV/c 2 , where the analysis is most sensitive, the observed (expected) limit is 0.7 pb (0.9 pb) at 95% Bayesian credibility level which is 1.7 (2.2) times the standard model cross section.

We measure the time dependence of the ratio of decay rates for the rare decay D{0}-->K{+}pi{-} to the Cabibbo-favored decay D{0}-->K{-}pi;{+}. A signal of 12.7x10;{3} D{0}-->K{+}pi{-} decays was obtained using the Collider Detector at Fermilab II detector at the Fermilab Tevatron with an integrated luminosity of 1.5 fb;{-1}. We measure the D0-D[over ]{0} mixing parameters (R_{D},y{'},x{'2}), and find that the data are inconsistent with the no-mixing hypothesis with a probability equivalent to 3.8 Gaussian standard deviations.

We report the first observation of single top quark production using 3.2 fb −1 of pp collision data with √ s = 1.96 TeV collected by the Collider Detector at Fermilab. The significance of the observed data is 5.0 standard deviations, and the expected sensitivity for standard model production and decay is in excess of 5.9 standard deviations. Assuming mt = 175 GeV/c 2 , we measure a cross section of 2.3 +0.6 −0.5 (stat + syst) pb, extract the CKM matrix element value |V tb | = 0.91 ± 0.11(stat + syst) ± 0.07(theory), and set the limit |V tb | > 0.71 at the 95% C.L.

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We report the observation of electroweak single top quark production in 3.2 fb −1 of pp collision data collected by the Collider Detector at Fermilab at √ s = 1.96 TeV. Candidate events in the W +jets topology with a leptonically decaying W boson are classified as signal-like by four parallel analyses based on likelihood functions, matrix elements, neural networks, and boosted decision trees. These results are combined using a super discriminant analysis based on genetically evolved neural networks in order to improve the sensitivity. This combined result is further combined with that of a search for a single top quark signal in an orthogonal sample of events with missing transverse energy plus jets and no charged lepton. We observe a signal consistent with the standard model prediction but inconsistent with the background-only model by 5.0 standard deviations, with a median expected sensitivity in excess of 5.9 standard deviations. We measure a production cross section of 2.3 +0.6 −0.5 (stat + sys) pb, extract the CKM matrix element value |V tb | = 0.91 +0.11 −0.11 (stat + sys) ± 0.07(theory), and set a lower limit |V tb | > 0.71 at the 95% confidence level, assuming mt = 175 GeV/c 2 .