Paper detail

Impact of dark scalars on the radiative $H^+ W^- Z$ vertex

An $H^+ W^- Z$ vertex, i.e, the interaction connecting a singly charged physical scalar to the $W^\pm,~Z$ gauge bosons is absent at the tree level in a scalar sector comprising only $SU(2)_L$ doublets. However, the interaction can be generated radiatively in such a case, an example of which is a two-Higgs doublet model. In this study, we extend a two-Higgs doublet scenario by additional $SU(2)_L$ scalar doublets. Upon endowing with appropriate discrete symmetries, these additional doublets so introduced can furnish successful candidates of dark matter. Interestingly, the same "dark" scalars can also radiatively enhance the strength of the $H^+ W^- Z$ interaction. We compute the $H^+ W^- Z$ vertex at one-loop in a non-linear gauge that eliminates certain unphysical interactions. While all possible constraints are taken into account in doing so, particular emphasis is given to the ones stemming from dark matter. Correlations between the dark matter observables and the $H^+ W^- Z$ interaction-strength are studied. The study thus connects a radiatively generated $H^+ W^- Z$ vertex to dark matter phenomenology.