Measurement of lepton differential distributions and the top quark mass in t(t)over-bar production in pp collisions at a root s=8TeV with the ATLAS detector


Aaboud M., Aad G., Abbott B., Abdinov O., Abeloos B., Abidi S. H. , ...More

EUROPEAN PHYSICAL JOURNAL C, vol.77, no.11, 2017 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 77 Issue: 11
  • Publication Date: 2017
  • Doi Number: 10.1140/epjc/s10052-017-5349-9
  • Title of Journal : EUROPEAN PHYSICAL JOURNAL C

Abstract

This paper presents single lepton and dilepton kinematic distributions measured in dileptonic t(t)over-bar events produced in 20.2 fb(-1) of root 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 e mu 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 m(t)(pole) = 173.2 +/- 0.9 +/- 0.8 +/- 1.2 GeV, where the three uncertainties arise from data statistics, experimental systematics, and theoretical sources.