Perturbative Unitarity Constraints on Gauge Portals

Understand

Dark matter that was once in thermal equilibrium with the Standard Model is generally prohibited from obtaining all of its mass from the electroweak phase transition.

• This implies a new scale of physics and mediator particles to facilitate dark matter annihilation.
• In this work, we focus on dark matter that annihilates through a generic gauge boson portal.
• We show how partial wave unitarity places upper bounds on the dark gauge boson, dark Higgs and dark matter masses.