Quasi-degenerate dark photon and dark matter

TL;DR

This paper proposes a non-abelian dark sector with an $SU(2)_X$ gauge symmetry, where kinetic mixing with the Standard Model leads to a dark photon and stable dark matter particles with nearly degenerate masses, offering testable predictions.

Contribution

It introduces a novel non-abelian dark sector model with kinetic mixing, resulting in nearly degenerate dark photon and dark matter, which is a new approach compared to previous abelian models.

Findings

Dark photon and dark matter can have nearly degenerate masses.

The model predicts observable signals if both particles are detected.

The framework avoids fermions in the dark sector, simplifying the model.

Abstract

We introduce an $SU(2)_X^{}$ dark sector without any fermions and then realize a non-abelian kinetic mixing between the dark $SU(2)_X^{}$ gauge fields and the standard model $SU(2)_L^{}\times U(1)_Y^{}$ gauge fields. While one of the dark gauge bosons becomes a dark photon, the others can keep stable to form a dark matter particle. The nearly degenerate masses of dark photon and dark matter could be tested if the dark photon and the dark matter are both observed in the future.