Model-independent determination of the strong-phase difference between D0 and D⊃̄0→KS,L0h+h- (h=π, K) and its impact on the measurement of the CKM angle γ/Φ3
Physical Review D - Particles, Fields, Gravitation and Cosmology 82:11 (2010)
Abstract:
We report the first determination of the relative strong-phase difference between D0→KS,L0K+K- and D⊃̄0→KS, L0K+K-. In addition, we present updated measurements of the relative strong-phase difference between D0→KS, L0π+π- and D⊃̄0→KS,L0π +π-. Both measurements exploit the quantum coherence between a pair of D0 and D⊃̄0 mesons produced from ψ(3770) decays. The strong-phase differences measured are important for determining the Cabibbo-Kobayashi-Maskawa angle γ/Φ3 in B -→K-D⊃0 decays, where D⊃0 is a D0 or D⊃̄0 meson decaying to KS0h+h- (h=π, K), in a manner independent of the model assumed to describe the D0→KS0h +h- decay. Using our results, the uncertainty in γ/Φ3 due to the error on the strong-phase difference is expected to be between 1.7° and 3.9° for an analysis using B -→K-D⊃0, D⊃0→KS0π+π - decays, and between 3.2° and 3.9° for an analysis based on B-→K-D⊃0, D⊃0→KS0K+K - decays. A measurement is also presented of the CP-odd fraction, F-, of the decay D0→KS0K+K- in the region of the Φ→K+K- resonance. We find that in a region within 0.01GeV2/c4 of the nominal Φ mass squared F->0.91 at the 90% confidence level. © 2010 The American Physical Society.Erratum: Measurement of particle production and inclusive differential cross sections in pp̄ collisions at √s=1.96TeV (Physical Review D - Particles, Fields, Gravitation and Cosmology)
Physical Review D - Particles, Fields, Gravitation and Cosmology 82:11 (2010)
Observation of single top quark production and measurement of
Physical Review D - Particles, Fields, Gravitation and Cosmology 82:11 (2010)
Abstract:
We report the observation of electroweak single top quark production in 3.2fb⊃-1 of pp̄ collision data collected by the Collider Detector at Fermilab at √s=1.96TeV. 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 2.3-0.5+0.6(stat+sys)pb, extract the value of the Cabibbo-Kobayashi-Maskawa matrix element |Vtb|=0.91-0.11+0. 11(stat+sys)±0.07(theory), and set a lower limit |Vtb|>0.71 at the 95%C.L., assuming mt=175GeV/c2.Measurement of σ(pp→bb̄X) at √s=7 TeV in the forward region
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 694:3 (2010) 209-216
Abstract:
Decays of b hadrons into final states containing a D0 meson and a muon are used to measure the bb̄ production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV at the LHC. In the pseudorapidity interval 2<η<6 and integrated over all transverse momenta we find that the average cross-section to produce b-flavoured or b̄-flavoured hadrons is (75.3±5.4±13.0) μb. © 2010 CERN.Search for R-parity violating decays of sneutrinos to eμ, μτ, and eτ pairs in pp collisions at square root s = 1.96 TeV.
Phys Rev Lett 105:19 (2010) 191801