Effects of Two Inert Scalar Doublets on Higgs Interactions and Electroweak Phase Transition

Understand

We study some implications of the presence of two inert scalar doublets which are charged under a dark Abelian gauge symmetry.

• Specifically, we investigate the effects of the new scalars on oblique electroweak parameters and on the interactions of the 125 GeV Higgs boson, especially its decay modes $h\to\gamma\gamma,\gamma Z$, and trilinear coupling, all of which will be probed with improved precision in future Higgs measurements.
• Moreover, we explore how the inert scalars may give rise to strongly first-order electroweak phase transition and also show its correlation with sizable modifications to the Higgs trilinear coupling.