Minimal nonabelian model of atomic dark matter

TL;DR

This paper proposes a minimal nonabelian dark matter model with a hidden SU(2) gauge symmetry, explaining matter abundance via leptogenesis and predicting unique bound states and multiple interaction portals with potential experimental signatures.

Contribution

It introduces a simplified nonabelian dark matter model with specific gauge symmetry breaking and fermion content, enabling leptogenesis and multiple detection avenues.

Findings

Achieves dark matter asymmetry through leptogenesis.

Predicts exotic bound states with unique properties.

Identifies three portals to the standard model for experimental tests.

Abstract

A dark sector resembling the standard model, where the abundance of matter is explained by baryon and lepton asymmetries, and stable constituents bind to form atoms, is a theoretically appealing possibility. We show that a minimal model with a hidden SU(2) gauge symmetry broken to U(1), with a Dirac fermion doublet, suffices to realize this scenario. Supplemented with a dark Higgs doublet that gets no VEV, we readily achieve the dark matter asymmetry through leptogenesis. The model can simultaneously have three portals to the standard model, through the Higgs, nonabelian kinetic mixing, and the heavy neutrino, with interesting phenomenology for direct and collider searches, as well as cosmologically relevant DM self-interactions. Exotic bound states consisting of two fermions and a doubly-charged vector boson can exist in one phase of the theory.