tt¯bb¯ at the LHC: on the size of corrections and b-jet definitions

• Published in: The journal of high energy physics Vol. 2021; no. 8
• Main Authors: Bevilacqua, Giuseppe, Bi, Huan-Yu, Hartanto, Heribertus Bayu, Kraus, Manfred, Lupattelli, Michele, Worek, Malgorzata
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2021; Springer Nature B.V
• Subjects: Classical and Quantum Gravitation; Cross-sections; Decay; Distribution functions; Elementary Particles; Flavor (particle physics); High energy physics; Large Hadron Collider; Leptons; Mathematical analysis; Partons; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Quarks; Regular Article - Theoretical Physics; Relativity Theory; String Theory; NLO Computations; QCD Phenomenology
• ISSN: 1029-8479
• DOI: 10.1007/JHEP08(2021)008

A bstract We report on the calculation of the next-to-leading order QCD corrections to the production of a t t ¯ pair in association with two heavy-flavour jets. We concentrate on the di-lepton t t ¯ decay channel at the LHC with s = 13 TeV. The computation is based on pp → e + ν e μ − ν ¯ μ b b ¯ b b ¯ matrix elements and includes all resonant and non-resonant diagrams, interferences and off-shell effects of the top quark and the W gauge boson. As it is customary for such studies, results are presented in the form of inclusive and differential fiducial cross sections. We extensively investigate the dependence of our results upon variation of renormalisation and factorisation scales and parton distribution functions in the quest for an accurate estimate of the theoretical uncertainties. We additionally study the impact of the contributions induced by the bottom-quark parton density. Results presented here are particularly relevant for measurements of t t ¯ H ( H → b b ¯ ) and the determination of the Higgs coupling to the top quark. In addition, they might be used for precise measurements of the top-quark fiducial cross sections and to investigate top-quark decay modelling at the LHC.