TY  - JOUR
T1  - Search for light scalar top-quark pair production in final states with two leptons with the ATLAS detector in √s=7 TeV proton–proton collisions
JF  - The European Physical Journal C
N2  - A search is presented for the pair production of light scalar top quarks in √s=7 TeV proton–proton collisions recorded with the ATLAS detector at the Large Hadron Collider. This analysis uses the full data sample collected during 2011 running that corresponds to a total integrated luminosity of 4.7 fb\(^{−1}\). Light scalar top quarks are searched for in events with two opposite-sign leptons (e, μ), large missing transverse momentum and at least one jet in the final state. No excess over Standard Model expectations is found, and the results are interpreted under the assumption that the light scalar top decays to a b-quark in addition to an on-shell chargino whose decay occurs through a virtual W boson. If the chargino mass is 106 GeV, light scalar top-quark masses up to 130 GeV are excluded for neutralino masses below 70 GeV.
KW  - signal cross section
KW  - jet energy scale
KW  - jet energy scale uncertainty
KW  - dead region
KW  - jet energy resolution
KW  - top quark pair
KW  - charingo mass
KW  - top quark decay
KW  - SM background
KW  - simulaed event sample
KW  - MC simulation
KW  - visible cross section
KW  - anti-k jet
KW  - top event dilepton invariant mass
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-129561
VL  - 72
IS  - 2237
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  - 
TY  - JOUR
T1  - Measurement of \(t\overline t\) production with a veto on additional central jet activity in pp collisions at √s=7 TeV using the ATLAS detector
JF  - European Physical Journal C
N2  - A measurement of the jet activity in \(t\overline t\) events produced in proton–proton collisions at a centre-of-mass energy of 7 TeV is presented, using 2.05 fb\(^{−1}\) of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. The \(t\overline t\) events are selected in the dilepton decay channel with two identified b-jets from the top quark decays. Events are vetoed if they contain an additional jet with transverse momentum above a threshold in a central rapidity interval. The fraction of events surviving the jet veto is presented as a function of this threshold for four different central rapidity interval definitions. An alternate measurement is also performed, in which events are vetoed if the scalar transverse momentum sum of the additional jets in each rapidity interval is above a threshold. In both measurements, the data are corrected for detector effects and compared to the theoretical models implemented in MC@NLO, Powheg, Alpgen and Sherpa. The experimental uncertainties are often smaller than the spread of theoretical predictions, allowing deviations between data and theory to be observed in some regions of phase space.
KW  - jet reconstruction efficiency
KW  - jet energy scale
KW  - jet energy scale uncertainty
KW  - fiducial cross section
KW  - individual systematic uncertainty
KW  - jet energy resolution
KW  - systematic uncertainty
KW  - muon reconstruction efficiency
KW  - rapidity interval
KW  - pythia parton shower
KW  - jet transverse momentum
KW  - underlying event tune
KW  - particle level jet
KW  - additional jet
KW  - MC event generator
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128931
VL  - 72
IS  - 2043
ER  -