SIMP from a strong U(1) gauge theory with a monopole condensation

We provide a variant model of a strongly interacting massive particle (SIMP), where composite dark matter (DM) comes from a strongly interacting U(1) theory. We first explain a non-Abelian version of the model with an additional singlet field, which is mixed with the Higgs field to maintain kinetic equilibrium between the hidden and Standard Model (SM) sectors. The mixing leads to signals that would be detected by future collider experiments, direct DM detection experiments, and beam-dump experiments. Then we investigate a U(1) theory with a scalar monopole, where U(1) charged particles are confined by a monopole condensation. In this model, the radial component of the monopole can mix with the Higgs field, so that we do not need to introduce the additional singlet field.