Aad, G.Abbott, B.Abbott, D.C.Abeling, K.Abidi, S.H.Aboulhorma, A.Abramowicz, H.Abreu, H.Abulaiti, Y.Abusleme Hoffman, A.C.Acharya, B.S.Adam Bourdarios, C.Adamczyk, L.Adamek, L.Addepalli, S.V.Adelman, J.Adiguzel, A.Adorni, S.Adye, T.Affolder, A.A.et al.2023-12-192023-12-192023The Journal of High Energy Physics, 2023; 2023(7):1-541029-8479https://hdl.handle.net/2440/140241A search for the leptonic charge asymmetry (A `c) of top-quark-antiquark pair production in association with a W boson (ttW¯ ) is presented. The search is performed using final states with exactly three charged light leptons (electrons or muons) and is based on √ s = 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider at CERN during the years 2015–2018, corresponding to an integrated luminosity of 139 fb−1 . A profile-likelihood fit to the event yields in multiple regions corresponding to positive and negative differences between the pseudorapidities of the charged leptons from top-quark and top-antiquark decays is used to extract the charge asymmetry. At reconstruction level, the asymmetry is found to be −0.12 ± 0.14 (stat.) ± 0.05 (syst.). An unfolding procedure is applied to convert the result at reconstruction level into a charge-asymmetry value in a fiducial volume at particle level with the result of −0.11 ± 0.17 (stat.) ± 0.05 (syst.). The Standard Model expectations for these two observables are calculated using Monte Carlo simulations with next-to-leading-order plus parton shower precision in quantum chromodynamics and including next-to-leading-order electroweak corrections. They are −0.084 +0.005 −0.003 (scale) ± 0.006 (MC stat.) and −0.063 +0.007 −0.004 (scale) ± 0.004 (MC stat.) respectively, and in agreement with the measurements.en© 2023 CERN for the benefit of the ATLAS Collaboration. This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.Hadron-Hadron Scattering; Top PhysicsJournal article10.1007/JHEP07(2023)0332023-12-19650494