Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at √s=8 TeV with the ATLAS detector

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 kinematics. 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 AC =0.009±0.005 (stat.+ syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard Model.