Vector dark matter from a gauged $SU(2)$ symmetry

TL;DR

This paper introduces a dark matter model based on a hidden $SU(2)$ gauge symmetry broken by scalar fields, leading to stable vector dark matter and resonant annihilation, with detailed relic density and scattering cross section analysis.

Contribution

It presents a novel dark sector model with a gauged $SU(2)$ symmetry, deriving mass relations and stabilization mechanisms for vector dark matter.

Findings

Stable vector dark matter achieved via residual $Z_2$ symmetry.

Resonant dark matter annihilation explained by mass relations.

Parameter space consistent with relic density and direct detection constraints.

Abstract

We propose a scenario of dark sector described by a hidden $SU(2)$ gauge symmetry which is broken by a vacuum expectation value(VEV) of a scalar multiplet. We discuss a general mass relation among $SU(2)$ gauge bosons after spontaneous symmetry breaking which is determined by weight of gauge group representation associated with a scalar multiplet developing VEV. Then a model with quintet and triplet scalar fields is discussed in which hidden gauge boson can be dark matter(DM) stabilized by remnant discrete $Z_2$ symmetry and resonant dark matter annihilation is realized by mass relation between DM and mediator. We estimate relic density and spin independent DM-nucleon scattering cross section searching for allowed parameter region.