Measurement of the W+ W- production cross section and search for anomalous WWγ and WWZ couplings in pp collisions at square root(s)=1.96 TeV.
Phys Rev Lett 104:20 (2010) 201801
Abstract:
This Letter describes the current most precise measurement of the W boson pair production cross section and most sensitive test of anomalous WWγ and WWZ couplings in pp collisions at a center-of-mass energy of 1.96 TeV. The WW candidates are reconstructed from decays containing two charged leptons and two neutrinos. Using data collected by the CDF II detector from 3.6 fb(-1) of integrated luminosity, a total of 654 candidate events are observed with an expected background of 320±47 events. The measured cross section is σ(pp→W+ W- +X)=12.1±0.9(stat)-1.4+1.6(syst) pb, which is in good agreement with the standard model prediction. The same data sample is used to place constraints on anomalous WWγ and WWZ couplings.Measurement of the tt̄ production cross section in pp̄ collisions at √s=1.96TeV using soft electron b-tagging
Physical Review D - Particles, Fields, Gravitation and Cosmology 81:9 (2010)
Abstract:
We present a measurement of the top-quark pair-production cross section in pp̄ collisions at √s=1.96TeV using a data sample corresponding to 1.7fb-1 of integrated luminosity collected with the Collider Detector at Fermilab. We reconstruct tt̄ events in the lepton+jets channel, consisting of eν+jets and μν+jets final states. The dominant background is the production of W bosons in association with multiple jets. To suppress this background, we identify electrons from the semileptonic decay of heavy-flavor jets ("soft electron tags"). From a sample of 2196 candidate events, we obtain 120 tagged events with a background expectation of 51±3 events, corresponding to a cross section of σtt̄=7. 8±2.4(stat)±1.6(syst)±0.5(lumi)pb. We assume a top-quark mass of 175GeV/c2. This is the first measurement of the tt̄ cross section with soft electron tags in run II of the Tevatron. © 2010 The American Physical Society.Search for single top quark production in pp̄ collisions at √s=1.96TeV in the missing transverse energy plus jets topology
Physical Review D - Particles, Fields, Gravitation and Cosmology 81:7 (2010)
Abstract:
We report a search for single top quark production with the CDF II detector using 2.1fb-1 of integrated luminosity of pp̄ collisions at √s=1.96TeV. The data selected consist of events characterized by large energy imbalance in the transverse plane and hadronic jets, and no identified electrons and muons, so the sample is enriched in W→τν decays. In order to suppress backgrounds, additional kinematic and topological requirements are imposed through a neural network, and at least one of the jets must be identified as a b quark jet. We measure an excess of signal-like events in agreement with the standard model prediction, but inconsistent with a model without single top quark production by 2.1 standard deviations (σ), with a median expected sensitivity of 1.4σ. Assuming a top quark mass of 175GeV/c2 and ascribing the excess to single top quark production, the cross section is measured to be 4.9-2.2+2.5(stat+syst)pb, consistent with measurements performed in independent data sets and with the standard model prediction. © 2010 The American Physical Society.Erratum: Measurement of σ(e+e-→ψ(3770) →hadrons) at Ec.m.=3773MeV(Physical Review Letters (2006) 96 (092002))
Physical Review Letters 104:15 (2010)
Search for the Higgs Boson Using Neural Networks in Events with Missing Energy and b-Quark Jets in pp̄ Collisions at √s=1.96TeV
Physical Review Letters 104:14 (2010)