Allbrooke, B M M, Asquith, L, Cerri, A, Chavez Barajas, C A, De Santo, A, Salvatore, F, Santoyo Castillo, I, Shaw, K, Suruliz, K, Sutton, M R, Vivarelli, I, The ATLAS Collaboration, and others, (2014) Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s=7 TeV using the ATLAS detector. Journal of High Energy Physics, 2014 (2). a107 1-37. ISSN 1029-8479

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Abstract

This paper presents a measurement of the top quark pair (tt¯) production charge asymmetry AC using 4.7 fb−1 of proton-proton collisions at a centre-of-mass energy √s=7 TeV collected by the ATLAS detector at the LHC. A tt¯-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 tt¯ event kinematics. A Bayesian unfolding procedure is employed to estimate AC at the parton-level. The measured value of the tt¯ production charge asymmetry is AC = 0.006 ± 0.010, where the uncertainty includes both the statistical and the systematic components. Differential AC measurements as a function of the invariant mass, the rapidity and the transverse momentum of the tt¯ system are also presented. In addition, AC is measured for a subset of events with large tt¯ velocity, where physics beyond the Standard Model could contribute. All measurements are consistent with the Standard Model predictions.

Item Type:	Article
Schools and Departments:	School of Mathematical and Physical Sciences > Physics and Astronomy
Research Centres and Groups:	Experimental Particle Physics Research Group
Subjects:	Q Science > QC Physics
Depositing User:	Billy Wichaidit
Date Deposited:	05 May 2017 10:53
Last Modified:	14 Aug 2020 10:30
URI:	http://sro.sussex.ac.uk/id/eprint/67703

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