Aad, G.Abbott, B.Abbott, D.C.Abeling, K.Abidi, S.H.Aboulhorma, A.Çetin, Serkant Ali2024-05-192024-05-1920231029-8479https://doi.org/10.1007/JHEP07(2023)033https://hdl.handle.net/20.500.12713/4405A search for the leptonic charge asymmetry (Ac?) of top-quark-antiquark pair production in association with a W boson (tt¯ W) 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?0.003+0.005 (scale) ± 0.006 (MC stat.) and ?0.063?0.004+0.007 (scale) ± 0.004 (MC stat.) respectively, and in agreement with the measurements. [Figure not available: see fulltext.]. © 2023, The Author(s).eninfo:eu-repo/semantics/openAccessHadron-Hadron ScatteringTop PhysicsArticle202372-s2.0-8516410238210.1007/JHEP07(2023)033Q2