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arXiv · 2105.11478

Probing the spin correlations of $t\bar t $ production at NLO QCD+EW

Rikkert Frederix·Ioannis Tsinikos·Timea Vitos
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Abstract

In this work we investigate the NLO QCD+EW corrections to the top quark pair production and their effects on the spin correlation coefficients and asymmetries at fixed-order top quark pair production and LO decay in the dilepton channel, within the narrow-width approximation. The spin correlations are implicitly measured through the lepton kinematics. Moreover we study the EW effects to the leptonic differential distributions. We find that the EW corrections to the $t \bar t$ production are within the NLO QCD theoretical uncertainties for the spin correlation coefficients and the leptonic asymmetries. On the other hand, for the differential distributions we find that the EW corrections exceed the NLO QCD scale uncertainty band in the high rapidity regimes and are of the order of the NLO QCD scale uncertainty in the case of invariant mass and transverse momentum distributions.

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Rikkert Frederix, Ioannis Tsinikos, Timea Vitos. 2021-05-24. Probing the spin correlations of $t\bar t $ production at NLO QCD+EW. https://doi.org/10.1140/epjc%2Fs10052-021-09612-9

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