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

TL;DR

This paper analyzes the impact of combined NLO QCD and electroweak corrections on top quark pair production, focusing on spin correlations and leptonic distributions, revealing that EW effects are significant in certain kinematic regions.

Contribution

It provides a detailed calculation of NLO QCD+EW corrections to top pair production and their influence on spin observables and differential distributions at the LHC.

Findings

EW corrections are within NLO QCD uncertainties for spin correlations.

EW effects exceed NLO QCD uncertainties at high rapidity.

Electroweak corrections are comparable to NLO QCD uncertainties for some distributions.

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.