Measurement of the top quark pair production charge asymmetry in proton-proton 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

JOURNAL OF HIGH ENERGY PHYSICS, no.2, 2014 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2014
  • Doi Number: 10.1007/jhep02(2014)107
  • Title of Journal : JOURNAL OF HIGH ENERGY PHYSICS

Abstract

This paper presents a measurement of the top quark pair () production charge asymmetry A (C) using 4.7 fb(-1) of proton-proton collisions at a centre-of-mass energy root s = 7 TeV collected by the ATLAS detector at the LHC. A -enriched sample of events with a single lepton (electron or muon), missing transverse momentum and at least four high transverse momentum jets, of which at least one is tagged as coming from a b-quark, is selected. A likelihood fit is used to reconstruct the event kinematics. A Bayesian unfolding procedure is employed to estimate A (C) at the parton-level. The measured value of the production charge asymmetry is A (C) = 0.006 +/- 0.010, where the uncertainty includes both the statistical and the systematic components. Differential A (C) measurements as a function of the invariant mass, the rapidity and the transverse momentum of the system are also presented. In addition, A (C) is measured for a subset of events with large velocity, where physics beyond the Standard Model could contribute. All measurements are consistent with the Standard Model predictions.