Measurement of the tt虅 production cross section in pp collisions at 鈭歴=7 TeV using the kinematic properties of events with leptons and jets
European Physical Journal C 71:9 (2011) 1-27
Abstract:
A measurement of the tt虅 production cross section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been performed at the LHC with the CMS detector. The analysis uses a data sample corresponding to an integrated luminosity of 36 pb-1and is based on the reconstruction of the final state with one isolated, high transverse-momentum electron or muon and three or more hadronic jets. The kinematic properties of the events are used to separate the tt虅 signal from W+jets and QCD multijet background events. The measured cross section is 173+39-32(stat. + syst.) pb, consistent with standard model expectations. 漏 2011 CERN for the benefit of the CMS collaboration.Search for an excess of events with an identical flavour lepton pair and significant missing transverse momentum in 鈭歴 = TeV proton-proton collisions with the ATLAS detector
European Physical Journal C 71:7 (2011) 1-18
Abstract:
Results are presented of a search for particles decaying into final states with significant missing transverse momentum and exactly two identical flavour leptons (e, 渭) of opposite charge in 鈭歴 = TeV collisions at the Large Hadron Collider. This channel is particularly sensitive to supersymmetric particle cascade decays producing flavour correlated lepton pairs. Flavour uncorrelated backgrounds are subtracted using a sample of opposite flavour lepton pair events. Observation of an excess beyond Standard Model expectations following this subtraction procedure would offer one of the best routes to measuring the masses of supersymmetric particles. In a data sample corresponding to an integrated luminosity of 35 pb-1 no such excess is observed. Model-independent limits are set on the contribution to these final states from supersymmetry and are used to exclude regions of a phenomenological supersymmetric parameter space. 漏 2011 CERN for the benefit of the ATLAS collaboration.Search for supersymmetric particles in events with lepton pairs and large missing transverse momentum in 鈭歴 = 7 TeV proton-proton collisions with the ATLAS experiment
European Physical Journal C 71:7 (2011) 18-19
Abstract:
Results are presented of searches for the production of supersymmetric particles decaying into final states with missing transverse momentum and exactly two isolated leptons in 鈭歴 = 7 TeV proton-proton collisions at the Large Hadron Collider. Search strategies requiring lepton pairs with identical-sign or opposite-sign electric charges are described. In a data sample corresponding to an integrated luminosity of 35 pb-1 collected with the ATLAS detector, no significant excesses are observed. Based on specific benchmark models, limits are placed on the squark mass between 450 and 690 GeV for squarks approximately degenerate in mass with gluinos, depending on the supersymmetric mass hierarchy considered. 漏 2011 CERN for the benefit of the ATLAS collaboration.Missing transverse energy performance of the CMS detector
ArXiv 1106.5048 (2011)
Search for New Physics with a Mono-Jet and Missing Transverse Energy in pp Collisions at sqrt(s) = 7 TeV
ArXiv 1106.4775 (2011)