Measurement of the top quark pair production charge asymmetry in proton-proton collisions at s√ = 7 TeV using the ATLAS detector

ATLAS COLLABORATION, G. AAD, F. MONTICELLI, ET AL

JOURNAL OF HIGH ENERGY PHYSICS

SPRINGER

Lugar: Berlin; Año: 2014 vol. 231 p. 1 - 23

1126-6708

This paper presents a measurement of the top quark pair (tt) production charge asymmetry AC√−1using 4.7 fb 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 eventkinematics. 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 uncertaintyincludes 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 ̄ velocity, where physicspresented. In addition, AC is measured for a subset of events with large ttbeyond the Standard Model could contribute. All measurements are consistent with the StandardModel predictions.