Asymmetric Dark Matter from a GeV Hidden Sector

TL;DR

This paper proposes a model where a GeV-scale dark matter arises from a hidden sector connected via gauge kinetic mixing, explaining the dark matter abundance and providing testable predictions for direct detection experiments.

Contribution

It introduces a mechanism generating the GeV dark matter mass scale from the weak scale through gauge kinetic mixing and links baryon asymmetry to dark matter in a novel way.

Findings

Dark matter mass naturally around a few GeV

Suppressed symmetric dark matter abundance via dark photon annihilations

Predicted direct detection cross section within current experimental sensitivity

Abstract

Asymmetric Dark Matter (ADM) models relate the dark matter density to the baryon asymmetry, so that a natural mass scale for ADM is around a few GeV. In existing models of ADM, this mass scale is unexplained; here we generate this GeV scale for dark matter (DM) from the weak scale via gauge kinetic mixing with a new Abelian dark force. In addition, this dark sector provides an efficient mechanism for suppressing the symmetric abundance of DM through annihilations to the dark photon. We augment this sector with a higher dimensional operator responsible for communicating the baryon asymmetry to the dark sector. Our framework also provides DM candidate for gauge mediation models. It results in a direct detection cross section of interest for current experiments: sigma less than or similar to 10^{-42} cm^2 for DM masses in the range 1 - 15 GeV.