Measurement of the bottom-strange meson mixing phase in the full CDF data set
Physical Review Letters 109:17 (2012)
Abstract:
We report a measurement of the bottom-strange meson mixing phase βs using the time evolution of Bs0→J/ ψ(→μ+μ-)(→K+K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at √s=1.96TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6fb -1 of integrated luminosity. We report confidence regions in the two-dimensional space of βs and the Bs0 decay-width difference ΔΓs and measure βs [-π/2,-1.51] [-0.06,0.30] [1.26,π/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of βs, we also determine ΔΓs=0.068±0. 026(stat)±0.009(syst)ps-1 and the mean Bs0 lifetime τs=1.528±0.019(stat)±0.009(syst)ps, which are consistent and competitive with determinations by other experiments. © 2012 American Physical Society.Measurement of the Mass Difference Between Top and Anti-top Quarks at CDF
(2012)
Inclusive and differential measurements of the tt- charge asymmetry in proton-proton collisions at s=7 TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 717:1-3 (2012) 129-150
Abstract:
The tt- charge asymmetry is measured in events containing a charged lepton (electron or muon) and at least four jets, one of which is identified as originating from b-quark hadronization. The analyzed dataset corresponds to an integrated luminosity of 5.0 fb-1 collected with the CMS detector at the LHC. An inclusive and three differential measurements of the tt- charge asymmetry as a function of rapidity, transverse momentum, and invariant mass of the tt- system are presented. The measured inclusive tt- charge asymmetry is AC=0.004±0.010(stat.)±0.011(syst.). This result and the three differential measurements are consistent with zero asymmetry as well as with the predictions of the standard model. © 2012 CERN.Search for a Higgs boson in the diphoton final state using the full CDF data set from pp collisions at s=1.96TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 717:1-3 (2012) 173-181
Abstract:
A search for a narrow Higgs boson resonance in the diphoton mass spectrum is presented based on data corresponding to 10fb -1 of integrated luminosity collected by the CDF experiment from proton-antiproton collisions at s=1.96TeV. To increase the sensitivity of the search, we employ a multivariate discriminant technique for the first time in this channel at CDF. No evidence of signal is observed, and upper limits are set on the cross section times branching ratio of the resonant state as a function of the Higgs boson mass. The limits are interpreted in the context of the standard model with an expected (observed) limit on the cross section times branching ratio of 9.9 (17.0) times the standard model prediction at the 95% credibility level for a Higgs boson mass of 125GeV/c 2. Moreover, a Higgs boson with suppressed couplings to fermions is excluded for masses below 114GeV/c 2 at the 95% credibility level. © 2012 Elsevier B.V.Search for heavy Majorana neutrinos in μ±μ±+jets and e±e±+jets events in pp collisions at s=7TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 717:1-3 (2012) 109-128