Decay modeling in 4top production

Abstract

We present NLO QCD predictions for the $pp\to t\bar{t}t\bar{t}+X$ process in the 4 lepton decay channel at the integrated and differential level for the LHC centre-of-mass energy of $\sqrt{s}=13.6$~TeV. Specifically, we compare the fixed order NLO QCD calculations to the parton-shower matched results obtained with \textsc{MC@NLO} and \textsc{Powheg} matching. In the former, NLO QCD corrections are consistently included in the production and decay of the four top quarks, preserving all spin correlations. In the latter, higher order effects in top-quark decays with approximate spin correlations are simulated in the parton showers, using Pythia. Additionally the impact of including matrix element corrections in the top quark decays in the parton-shower matched predictions is analysed.