Dark Z-mediated dark matter with verifiable exotic scalars

TL;DR

This paper explores a dark matter model involving a dark Z boson that mixes with the SM Z boson, introducing exotic scalars from an extended Higgs sector, and analyzes constraints and future detection prospects.

Contribution

It presents a novel dark matter scenario with a dark Z mediator and exotic scalars from an extended Higgs sector, linking collider and dark matter constraints.

Findings

Current constraints limit the parameter space.

Future collider searches can probe part of the model.

Exotic scalars offer new detection channels.

Abstract

In this work, we study a dark matter scenario where a dark Z boson possessing mass mixing with the SM Z boson couples to the DM candidate and serves as the portal to the SM. The UV origin of the mass mixing in the form of an extra dark Higgs doublet and a scalar dark singlet provides new exotic scalars which can constitute the final state of DM annihilation during freeze-out. We find that existing constraints on the observed Higgs coupling strength, exotic Higgs searches and dark matter observables complement each other, while future searches for exotic Higgs decays and resonant heavy scalars at HL-LHC will be sensitive to part of the allowed parameter space.