TY  - JOUR
T1  - A search for \(t\overline t\) resonances with the ATLAS detector in 2.05 fb\(^{−1}\) of proton-proton collisions at √s=7 TeV
JF  - European Physical Journal C
N2  - A search for top quark pair resonances in final states containing at least one electron or muon has been performed with the ATLAS experiment at the CERN Large Hadron Collider. The search uses a data sample corresponding to an integrated luminosity of 2.05 fb\(^{−1}\), which was recorded in 2011 at a proton-proton centre-of-mass energy of 7 TeV. No evidence for a resonance is found and limits are set on the production cross-section times branching ratio to \(t\overline t\) for narrow and wide resonances. For narrow Z′ bosons, the observed 95 % Bayesian credibility level limits range from 9.3 pb to 0.95 pb for masses in the range of m Z′=500 GeV to m\(_{Z′}\)=1300 GeV. The corresponding excluded mass region for a leptophobic topcolour Z′ boson (Kaluza-Klein gluon excitation in the Randall-Sundrum model) is m\(_{Z′}\)<880 GeV (m\(_{gKK}\)<1130 GeV).
KW  - dilepton invariant mass
KW  - dilepton channel
KW  - jet channel
KW  - top quark mass
KW  - heavy flavour quark
KW  - reconstructed mass spectrum
KW  - muon channel
KW  - single top production
KW  - electron energy deposition
KW  - multijet background
KW  - non-prompt lepton
KW  - light quark jet
KW  - jet sample
KW  - pair invariant mass
KW  - event selcetion cut
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127959
VL  - 72
IS  - 2083
ER  - 
TY  - JOUR
T1  - Measurement of the charge asymmetry in top quark pair production in pp collisions at √s=7 TeV using the ATLAS detector
JF  - The European Physical Journal C
N2  - A measurement of the top-antitop production charge asymmetry A C is presented using data corresponding to an integrated luminosity of 1.04 fb\(^{−1}\) of pp collisions at √s=7 TeV collected by the ATLAS detector at the LHC. Events are selected with a single lepton (electron or muon), missing transverse momentum and at least four jets of which at least one jet is identified as coming from a b-quark. A kinematic fit is used to reconstruct the t\(\overline t\) event topology. After background subtraction, a Bayesian unfolding procedure is performed to correct for acceptance and detector effects. The measured value of A\(_C\) is AC=−0.019±0.028 (stat.)±0.024 (syst.), consistent with the prediction from the MC@NLO Monte Carlo generator of A\(_C\) =0.006±0.002. Measurements of A\(_C\) in two ranges of invariant mass of the top-antitop pair are also shown.
KW  - jet multiplicity
KW  - B-tagged jet
KW  - systematic uncertainty
KW  - jet energy resolution
KW  - top quark masse
KW  - muon channel
KW  - jet scale energy
KW  - light quark jet
KW  - heavy flavour
KW  - single top production
KW  - single top event
KW  - fake lepton
KW  - top quark pair
KW  - multijet background
KW  - JES
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128904
VL  - 72
IS  - 2039
ER  - 
TY  - JOUR
T1  - Measurement of the top quark mass with the template method in the \(t\overline t\)→lepton+jets channel using ATLAS data
JF  - The European Physical Journal C
N2  - The top quark mass has been measured using the template method in the \(t\overline t\)→lepton+jets channel based on data recorded in 2011 with the ATLAS detector at the LHC. The data were taken at a proton-proton centre-of-mass energy of √s=7 TeV and correspond to an integrated luminosity of 1.04 fb\(^{−1}\). The analyses in the e+jets and μ+jets decay channels yield consistent results. The top quark mass is measured to be m\(_{top}\)=174.5±0.6\(_{stat}\)±2.3\(_{syst}\) GeV.
KW  - JES uncertainty
KW  - jet energy scale
KW  - top quark mass
KW  - jet channel
KW  - single top quark
KW  - jet energy scale uncertainty
KW  - systematic uncertainty
KW  - calorimeter response
KW  - simulated signal event
KW  - top quark decay
KW  - jet reconstruction efficiency
KW  - jet energy measurement
KW  - light quark jet
KW  - single top quark production
KW  - inclusive jet sample
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128912
VL  - 72
IS  - 2046
ER  -