Pseudo-Nambu-Goldstone Dark Matter from Non-Abelian Gauge Symmetry

TL;DR

This paper introduces a novel pseudo-Nambu-Goldstone boson dark matter model based on a non-Abelian gauge symmetry, which naturally stabilizes the dark matter candidate and aligns with current experimental constraints.

Contribution

It presents a new pNGB dark matter model from an $SU(2)_D$ gauge symmetry that avoids direct detection constraints through its global symmetry properties.

Findings

Dark matter relic density can be achieved with mass > half the Higgs mass.

Model parameters influence the upper limit from direct detection.

The dark matter candidate is stable due to a global custodial symmetry.

Abstract

We propose a pseudo-Nambu-Goldstone boson (pNGB) dark matter (DM) model based on an additional non-Abelian gauge symmetry $SU(2)_D$. The gauge symmetry $SU(2)_D$ is spontaneously broken to a global custodial symmetry $U(1)_V$ via the nonvanishing vacuum expectation values of $SU(2)_D$ doublet and triplet scalar fields. Due to the exact global symmetry $U(1)_V$, the lightest $U(1)_V$ charged particle becomes stable. We assume that the lightest charged particle in the model is the charged complex pNGB, which we regard as DM. It avoids the strong constraints from current DM direct detection experiments due to the property of NGB. We find that the measured energy density of DM can be reproduced when the DM mass is larger than the half of the Higgs mass, where the lower limit generally comes from the constraint of DM invisible decay and the upper limit from DM direct detection experiments depends on the model parameters.