Production and decay of the Higgs boson in association with top quarks

We report on the calculation of the next-lo-leading order QCD corrections to Higgs boson production and decay in association with top quarks. We consider leptonic decays of top quarks leading to the hadronic process pp -> e(+) V-e mu(-) (V) over bar (mu) b (b) over bar H (H -> X) at the LHC with root s = 13 TeV. All resonant as well as non-resonant Feynman diagrams, interferences and off-shell effects are included for the top quark and W gauge boson. Decays of the Higgs boson, on the other hand, are included in the narrow-width approximation. Specifically, we consider Higgs boson decays into b (b) over bar, T+T-, gamma gamma and e(+)e(-)e(+)e(-). Numerical results are given at the integrated and differential fiducial level for various factorisation and renormalisation scale choices and different PDF sets. We study the main theoretical uncertainties that are associated with neglected higher order terms in the perturbative expansion and with different parametrisations of the PDFs. Furthermore, we examine the size of the off-shell effects by an explicit comparison to the calculation in the full narrow-width approximation. Finally, the impact of the contributions induced by the bottom-quark parton density is investigated.

Automated summary

This study reports on the calculation of next-to-leading order QCD corrections to Higgs boson production and decay associated with top quarks, considering hadronic processes resulting from top quark decays. Resonant and non-resonant Feynman diagrams, interferences, and off-shell effects are thoroughly investigated, along with the inclusion of Higgs boson decays in the narrow-width approximation. Different theoretical uncertainties and the impact of bottom-quark parton density contributions are also examined.