Measurement of the mass difference between top and anti-top quarks in pp collisions at root s=7 TeV using the ATLAS detector


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Aad G., Abajyan T., Abbott B., Abdallah J., Khalek S. A., Abdinov O., ...More

PHYSICS LETTERS B, vol.728, pp.363-379, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 728
  • Publication Date: 2014
  • Doi Number: 10.1016/j.physletb.2013.12.010
  • Journal Name: PHYSICS LETTERS B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.363-379
  • Middle East Technical University Affiliated: Yes

Abstract

A measurement of the mass difference between top and anti-top quarks is presented. In a 4.7 fb(-1) data sample of proton-proton collisions at root s = 7 TeV recorded with the ATLAS detector at the LHC, events consistent with t (t) over bar production and decay into a single charged lepton final state are reconstructed. For each event, the mass difference between the top and anti-top quark candidate is calculated. A two b-tag requirement is used in order to reduce the background contribution. A maximum likelihood fit to these per-event mass differences yields Delta m = m(t) - m((t) over bar) = 0.67 +/- 0.61 (stat) +/- 0.41 (syst) GeV, consistent with CPT invariance. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.