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

Abstract

Abstract Assuming the existence of a new real scalar singlet $$s^0$$ s0 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 $$W^+W^-(\gamma )$$ W+W-(γ) , showing that they can give a contribution as large as $${{\mathcal {O}}}$$ O (5%) and $${{\mathcal {O}}}$$ O (7%), respectively. We also explicitly analyze in detail their dependence on the heavy mass $$m_S$$ mS and on the scalar mixing angle $$\alpha $$ α , finding that, especially in the large-mass region, these depend on the sign and the assumed value of $$\sin \alpha $$ sinα .