This paper presents single lepton and dilepton kinematic distributions measured in dileptonic tt events produced in 20.2 fb−1 of √s = 8 TeV pp collisions recorded by the ATLAS experiment at the LHC. Both absolute and normalised differential cross-sections are measured, using events with an opposite-charge eµ pair and one or two b-tagged jets. The cross-sections are measured in a fiducial region corresponding to the detector acceptance for leptons, and are compared to the predictions from a variety of Monte Carlo event generators, as well as fixed-order QCD calculations, exploring the sensitivity of the cross-sections to the gluon parton distribution function. Some of the distributions are also sensitive to the top quark pole mass; a combined fit of NLO fixed-order predictions to all the measured distributions yields a top quark mass value of mpolet = 173.2 ± 0.9 ± 0.8 ± 1.2 GeV, where the three uncertainties arise from data statistics, experimental systematics, and theoretical sources.
|Original language||English (US)|
|State||Published - Sep 27 2017|
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