This paper reports inclusive and differential measurements of the tt charge asymmetry A C in 20.3 fb −1 of √ s = 8 TeV pp collisions recorded by the ATLAS experiment at the Large Hadron Collider at CERN. Three differential measurements are performed as a function of the invariant mass, transverse momentum and longitudinal boost of the tt system. The tt pairs are selected in the single-lepton channels (e or µ) with at least four jets, and a likelihood fit is used to reconstruct the tt event

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... atics. A Bayesian unfolding procedure is performed to infer the asymmetry at parton level from the observed data distribution. The inclusive tt charge asymmetry is measured to be A C = 0.009 ± 0.005 (stat.+syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard Model. c 2016 CERN for the benefit of the ATLAS Collaboration. Reproduction of this article or parts of it is allowed as specified in the CC-BY-3.0 license. Event selection Only events recorded with an isolated or non-isolated single-electron or single-muon trigger under stable beam conditions with all detector subsystems operational are considered. The triggers have thresholds on p ℓ T , the transverse momentum (energy) of the muon (electron). These thresholds are 24 GeV for isolated single-lepton triggers and 60 (36) GeV for non-isolated single-electron (single-muon) triggers. Events satisfying the trigger selection are required to have at least one reconstructed vertex with at least five associated tracks of p T > 400 MeV, consistent with originating from the beam collision region in the x-y plane. If more than one vertex is found, the hard-scatter PV is taken to be the one which has the largest sum of the squared transverse momenta of its associated tracks. Events are required to have exactly one candidate electron or muon and at least four jets satisfying the quality and kinematic criteria discussed in Sect. 3. The selected lepton is required to match, with ∆R < 0.15, the lepton reconstructed by the high-level trigger. Events with additional electrons satisfying a looser