Radiative corrections of heavy scalar decays to gauge bosons in the singlet extension of the Standard Model

Abstract

Assuming the existence of a new real scalar singlet $s^0$ coupled to the Standard Model via a scalar quartic portal interaction, we compute the radiative corrections to the decay rates of the heavy scalar mass eigenstate to a couple of gauge bosons $ZZ$ and $W^{+}{W}^{-}(\gamma )$, showing that they can give a contribution as large as $\mathcal{O}$(5\%) and $\mathcal{O}$(7\%), respectively. We also explicitly analyze in detail their dependence on the heavy mass $m_S$ and on the scalar mixing angle $\alpha$, finding that, especially in the large-mass region, these depend on the sign of $\sin \alpha$.

Comments: 23 pages, 7 figures