Production and decay of a heavy boson in association with top quarks

We briefly report on NLO QCD corrections to the 𝑝𝑝 → 𝑡 ¯ 𝑡𝐵 + 𝑋 process, where 𝐵 stands for 𝐻, 𝑊 ± or 𝑍 . In the calculation all double-, single and non-resonant Feynman diagrams, interferences and finite-width effects are included for the top quark and 𝑊 ± / 𝑍 gauge bosons. Numerical results are shown at the differential cross section level for various factorisation and renormalisation scale settings and a few PDF sets. The main theoretical uncertainties associated with neglected higher-order terms in the perturbative expansion and with different parametrisations of the PDFs are also discussed. Furthermore, we compare our complete predictions for 𝑝𝑝 → 𝑡 ¯ 𝑡𝐵 + 𝑋 in multi-lepton final states to the calculation in the narrow-width approximation.