Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV

Chatrchyan S., Khachatryan V., Sirunyan A. M., Tumasyan A., Adam W., Bergauer T., ...More

PHYSICS LETTERS B, vol.770, pp.50-71, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 770
  • Publication Date: 2017
  • Doi Number: 10.1016/j.physletb.2017.04.028
  • Journal Name: PHYSICS LETTERS B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.50-71
  • Keywords: CMS, Top quark physics, CPT VIOLATION, MODEL, BOSON
  • Middle East Technical University Affiliated: Yes


The invariance of the standard model (SM) under the CPT transformation predicts equality of particle and antiparticle masses. This prediction is tested by measuring the mass difference between the top quark and antiquark (Delta m(t) = m(t) - m((t) over bar)) that are produced in pp collisions at a center-of-mass energy of 8 TeV, using events with a muon or an electron and at least four jets in the final state. The analysis is based on data corresponding to an integrated luminosity of 19.6 fb(-1) collected by the CMS experiment at the LHC, and yields a value of Delta m(t) = 0.15 0.19 (stat) +/- 0.09(syst) GeV, which is consistent with the SM expectation. This result is significantly more precise than previously reported measurements. (C) 2017 The Author(s). Published by Elsevier B.V.