Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at ?s = 13 TeV

Abstract

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d? t) and chromomagnetic (?? t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb?1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048?0.087+0.095(stat)?0.029+0.020(syst),??t=?0.024?0.009+0.013(stat)?0.011+0.016(syst), and a limit is placed on the magnitude of | d? t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.] © 2020, The Author(s).