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Modeling top-quark decays in tt¯tt¯ production at the LHC

Manal Alsairafi*, Nikolaos Dimitrakopoulos†, and Malgorzata Worek‡

  • *Contact author: manal.alsairafi@rwth-aachen.de
  • †Contact author: ndimitrak@physik.rwth-aachen.de
  • ‡Contact author: worek@physik.rwth-aachen.de
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Phys. Rev. D 112, 114002 – Published 5 December, 2025

DOI: https://doi.org/10.1103/sm4n-3tcg

Abstract

We compare the fixed-order NLO QCD predictions for the pp→tt¯tt¯+X process in the 4ℓ decay channel with the parton-shower-based results obtained with the powheg and mc@nlo matching methods. In the first case, NLO QCD corrections are consistently included in both the tt¯tt¯ production step and the decays of the four top quarks, preserving all spin correlations. In the second approach, higher-order effects in top-quark decays with approximate spin correlations are simulated in the pythia parton-shower framework. Additionally, we analyze the impact of including the so-called matrix element corrections in top-quark decays in both parton-shower matched predictions. The comparison is performed at the integrated and differential fiducial cross-section level for the LHC center-of-mass energy of s=13.6  TeV.

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Outline

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Phys. Rev. D 112, 114002– Published 5 December, 2025
  • Received 21 July 2025
  • Accepted 7 November 2025
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