About the bosonic decays of heavy Higgs states in the (N)MSSM

The heavy, doublet-dominated Higgs bosons expected in Two-Higgs-Doublet-Model-like extensions of the Standard Model are obvious targets for searches at high-energy colliders, and considerable activity in this sense is currently employed in analyzing the results of the Large Hadron Collider. For sufficiently heavy states, the SU(2)${}_L$ symmetry drastically constrains the decays of these new scalars. In models that contain only additional Higgs doublets, fermionic decay channels are expected to dominate, although some bosonic modes may lead to cleaner signals. The situation is very different if the Higgs sector is further extended by singlet states and the singlet-dominated scalars are kinematically accessible, in which case the Higgs-to-Higgs widths may even become dominant. Yet, a quantitative interpretation of the experimental data in terms of a specific model also runs through the control of radiative corrections in this model. In this paper, we examine the bosonic decays of the heavy, doublet-dominated Higgs states in the MSSM and the NMSSM at full one-loop order, insisting on the impact of the SU(2)${}_L$ symmetry and the effects of infrared type, in particular, the emergence of sizable non-resonant contributions to the three-boson final states.