Radiative Mixing of the One Higgs Boson and Emergent Self-Interacting Dark Matter

TL;DR

This paper explores radiative mixing between the Higgs boson and other scalars, proposing models where such mixing is naturally small and leads to emergent self-interacting dark matter with a light mediator.

Contribution

It introduces novel scalar extension models where Higgs mixing occurs radiatively, resulting in a dark matter candidate with self-interactions and a light mediator.

Findings

Radiative mixing can naturally be small in scalar extensions.

Models with $Z_3$ and $A_4$ symmetries produce dark matter with self-interactions.

Emergence of a light mediator for dark matter interactions.

Abstract

In all scalar extensions of the standard model of particle interactions, the one Higgs boson responsible for electroweak symmetry breaking always mixes with other neutral scalars at tree level unless a symmetry prevents it. An unexplored important option is that the mixing may be radiative, and thus guaranteed to be small. Two first such examples are discussed. One is based on the soft breaking of the discrete symmetry $Z_3$. The other starts with the non-Abelian discrete symmetry $A_4$ which is then softly broken to $Z_3$, and results in the emergence of an interesting dark-matter candidate together with a light mediator for the dark matter to have its own long-range interaction.