Speaker
Description
We discuss the discovery prospects for a second Higgs doublet through the decay channels $A \to ZH$ and $H^+ \to W^+ H$. These decays are particularly relevant in two Higgs doublet models (2HDM) scenarios featuring a strong first-order electroweak phase transition, a necessary condition for successful electroweak baryogenesis. Within the general 2HDM, which allows flavor-changing neutral Higgs couplings, the scalar $H$ may decay dominantly via $t\bar c$ final state. We find that $A \to ZH$ and $H^+ \to W^+ H$ in the $\ell^+\ell^- t\bar c$ and $\ell^+\nu t\bar c$ final states provide a promising experimental avenue that complements existing searches for neutral and charged Higgs bosons at the LHC. The observation of such signatures would point to a very different 2HDM and may shed light on the mechanism behind the baryon asymmetry of the Universe.