$t\bar{t}t\bar{t}$: NLO QCD corrections in production and decays for the $3\ell$ channel

TL;DR

This paper presents NLO QCD corrections for four-top quark production at the LHC in the three-lepton decay channel, emphasizing the importance of higher-order effects and spin correlations using the narrow-width approximation.

Contribution

It provides a detailed calculation of NLO QCD corrections in both production and decay stages, preserving spin correlations without approximation.

Findings

QCD corrections significantly affect cross-section predictions

Results are sensitive to invariant mass cuts on light jets

Spin correlations are maintained at NLO accuracy

Abstract

We discuss the results for the four-top quark production process at the LHC at NLO accuracy in perturbative QCD for the $3\ell$ decay channel. The QCD corrections are applied in both the production and the decay stages of the four top quarks by employing the narrow-width approximation. The spin correlations are therefore preserved at NLO accuracy in QCD without any approximation. We summarize the impact of higher-order QCD effects by highlighting the sensitivity of the results on the cut applied on the invariant mass of the two hardest light jets in the process.