Dark Matter production from relativistic bubble walls

Understand

In this paper we present a novel mechanism for producing the observed Dark Matter(DM) relic abundance during the First Order Phase Transition (FOPT) in the early universe.

• We show that the bubble expansion with ultra-relativistic velocities can lead to the abundance of DM particles with masses much larger than the scale of the transition.
• We study this non-thermal production mechanism in the context of a generic phase transition and the electroweak phase transition.
• The application of the mechanism to the Higgs portal DM as well as the signal in the Stochastic Gravitational Background are discussed.