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

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

High energy physics ; Experimental particle physics ; LHC ; CMS ; Particle Physics Experiments ; Physics ; Vector boson scattering ; Hadron-Hadron scattering (experiments) ; Supersymmetry ; Higgs physics ; Particle and resonance production ; B physics ; Particle correlations and fluctuations ; Quarkonium ; Elementary Particles and Fields ; Beyond Standard Model ; Jets ; QCD ; Top physics ; Diboson ; Electroweak ; CKM matrix ; Top quark ; Large detector-systems performance ; Pattern recognition

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