64 research outputs found

    Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

    Get PDF
    The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of s=1.96\sqrt s =1.96 TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is AFBttˉ=0.128±0.025A_{\mathrm{FB}}^{t\bar{t}} = 0.128 \pm 0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions

    Inclusive Production of the X(4140)X(4140) State in ppp \overline p Collisions at D0

    No full text
    We present a study of the inclusive production of the X(4140)X(4140) with the decay to the J/ψϕJ/\psi \phi final state in hadronic collisions. Based on 10.4 fb110.4~\rm{fb^{-1}} of ppp \overline p collision data collected by the D0 experiment at the Fermilab Tevatron collider, we report the first evidence for the prompt production of X(4140)X(4140) and find the fraction of X(4140)X(4140) events originating from bb hadrons to be fb=0.39±0.07(stat)±0.10(syst)f_b=0.39\pm 0.07 {\rm \thinspace (stat)} \pm 0.10 {\rm \thinspace (syst)} . The ratio of the non-prompt X(4140)X(4140) production rate to the Bs0B_s^0 yield in the same channel is R=0.19±0.05(stat)±0.07(syst)R=0.19 \pm 0.05 {\rm \thinspace (stat)} \pm 0.07 {\rm \thinspace (syst)}. The values of the mass M=4152.5±1.7(stat)5.4+6.2(syst)M=4152.5 \pm 1.7 (\rm {stat}) ^{+6.2}_{-5.4} {\rm \thinspace (syst)}~MeV and width Γ=16.3±5.6(stat)±11.4(syst)\Gamma=16.3 \pm 5.6 {\rm \thinspace (stat)} \pm 11.4 {\rm \thinspace (syst)}~MeV are consistent with previous measurements. 8 pages, 2 figue

    Search for Violation of CPTCPT and Lorentz invariance in Bs0{B_s^0} meson oscillations

    No full text
    We present the first search for CPT-violating effects in the mixing of Bs0{B_s^0} mesons using the full Run II data set with an integrated luminosity of 10.4 fb1^{-1} of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay Bs0μ±Ds±B_s^0 \to \mu^\pm D_s^\pm as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPT- and Lorentz-invariance violating coupling coefficients. We find 95\% confidence intervals of Δa<1.2×1012\Delta a_{\perp} < 1.2 \times 10^{-12} GeV and (0.8<ΔaT0.396ΔaZ<3.9)×1013(-0.8 < \Delta a_T - 0.396 \Delta a_Z < 3.9) \times 10^{-13} GeV

    Precision measurement of the top-quark mass in lepton+jets final states

    No full text
    We measure the mass of the top quark in lepton++jets final states using the full sample of ppˉp\bar{p} collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at s=1.96\sqrt s=1.96 TeV, corresponding to 9.7fb19.7 {\rm fb}^{-1} of integrated luminosity. We use a matrix element technique that calculates the probabilities for each event to result from ttˉt\bar t production or background. The overall jet energy scale is constrained in situ by the mass of the WW boson. We measure mt=174.98±0.76m_t=174.98\pm0.76 GeV. This constitutes the most precise single measurement of the top-quark mass.We measure the mass of the top quark in lepton+jets final states using the full sample of pp¯ collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at s=1.96  TeV, corresponding to 9.7  fb−1 of integrated luminosity. We use a matrix element technique that calculates the probabilities for each event to result from tt¯ production or background. The overall jet energy scale is constrained in situ by the mass of the W boson. We measure mt=174.98±0.76  GeV. This constitutes the most precise single measurement of the top-quark mass.We measure the mass of the top quark in lepton++jets final states using the full sample of ppˉp\bar{p} collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at s=1.96\sqrt s=1.96 TeV, corresponding to 9.7fb19.7 {\rm fb}^{-1} of integrated luminosity. We use a matrix element technique that calculates the probabilities for each event to result from ttˉt\bar t production or background. The overall jet energy scale is constrained in situ by the mass of the WW boson. We measure mt=174.98±0.76m_t=174.98\pm0.76 GeV. This constitutes the most precise single measurement of the top-quark mass
    corecore