Abstract: The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d^t)(d^t) and chromomagnetic (?^t)(?^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 A(1)FBAFB(1) is used to approximate the asymmetry. Candidate tt¯tt¯ 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 tt¯tt¯ final states. The values found for the parameters are A(1)FB=0.048+0.095?0.087(stat)+0.020?0.029(syst),?^t=?0.024+0.013?0.009(stat)+0.016?0.011(syst),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??|d^t|< 0.03 at 95% confidence level.

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