An improved measurement of muon antineutrino disappearance in MINOS
(2012)
Measurement of the branching fraction B(Λb0→Λc+π -π +π -) at CDF
Physical Review D - Particles, Fields, Gravitation and Cosmology 85:3 (2012)
Abstract:
We report an analysis of the Λb0→Λc+π -π +π - decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4fb -1 of integrated luminosity. We reconstruct the currently largest samples of the decay modes Λb0→Λ c(2595) +π - (with Λ c(2595) +→Λc+π +π -), Λb0→Λ c(2625) +π - (with Λ c(2625) +→Λc+π +π -), Λb0→Σ c(2455) ++π -π - (with Σ c(2455) ++→Λc+π +), and Λb0→Σ c(2455)0π +π - (with Σ c(2455)0→Λc+π -) and measure the branching fractions relative to the Λb0→Λc+π - branching fraction. We measure the ratio B(Λb0→Λc+π -π +π -)/B(Λb0→Λc+π -)=3.04±0.33(stat)-0.55+0.70(syst) which is used to derive B(Λb0→Λc+π -π +π -)= (26.8-11.2+11.9)×10 -3. © 2012 American Physical Society.Measurement of the cross section for the production of a W boson in association with b-jets in pp collisions at √s=7TeV with the ATLAS detector
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 707:5 (2012) 438-458
Abstract:
A measurement is presented of the cross section for the production of a W boson with one or two jets, of which at least one must be a b-jet, in pp collisions at s=7TeV. Production via top decay is not included in the signal definition. The measurement is based on 35pb -1 of data collected with the ATLAS detector at the LHC. The W+b-jet cross section is defined for jets reconstructed with the anti-k t clustering algorithm with transverse momentum above 25 GeV and rapidity within ±2.1. The b-jets are identified by reconstructing secondary vertices. The fiducial cross section is measured both for the electron and muon decay channel of the W boson and is found to be 10.2±1.9(stat)±2.6(syst)pb for one lepton flavour. The results are compared with next-to-leading order QCD calculations, which predict a cross section smaller than, though consistent with, the measured value. © 2011 CERN.Measurement of the top quark pair production cross section in pp collisions at √s=7TeV in dilepton final states with ATLAS
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 707:5 (2012) 459-477
Abstract:
A measurement of the production cross section of top quark pairs (tt̄) in proton-proton collisions at a center-of-mass energy of 7 TeV recorded with the ATLAS detector at the Large Hadron Collider is reported. Candidate events are selected in the dilepton topology with large missing transverse energy and at least two jets. Using a data sample corresponding to an integrated luminosity of 35pb-1, a tt̄ production cross section σtt̄=177±20(stat.)±14(syst.)±7(lum.)pb is measured for an assumed top quark mass of mt=172.5GeV. A second measurement requiring at least one jet identified as coming from a b quark yields a comparable result, demonstrating that the dilepton final states are consistent with being accompanied by b-quark jets. These measurements are in good agreement with Standard Model predictions. © 2011 CERN.Search for anomalous production of multiple leptons in association with W and Z bosons at CDF
(2012)