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arXiv · 2205.02314

Search for CP violation using $\mathrm{t\bar{t}}$ events in the lepton+jets channel in pp collisions at $\sqrt{s}$ = 13 TeV

CMS Collaboration
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Abstract

Results are presented on a search for CP violation in the production and decay of top quark-antiquark pairs in the lepton+jets channel. The search is based on data from proton-proton collisions at 13 TeV, collected with the CMS detector, corresponding to an integrated luminosity of 138 fb$^{-1}$. Possible CP violation effects are evaluated by measuring uncorrected asymmetries in observables constructed from linearly independent four-momentum vectors of the final-state particles. The dimensionless chromoelectric dipole moment of the top quark obtained from the observed asymmetries is measured to be 0.04 $\pm$ 0.10 (stat) $\pm$ 0.07 (syst), and the asymmetries exhibit no evidence for CP-violating effects, consistent with expectations from the standard model.

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CMS Collaboration. 2022-05-04. Search for CP violation using $\mathrm{t\bar{t}}$ events in the lepton+jets channel in pp collisions at $\sqrt{s}$ = 13 TeV. https://doi.org/10.1007/jhep06(2023)081

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