Freeze-in through portals

Understand

The popular freeze-out paradigm for Dark Matter (DM) production, relies on DM-baryon couplings of the order of the weak interactions.

• However, different search strategies for DM have failed to provide a conclusive evidence of such (non-gravitational) interactions, while greatly reducing the parameter space of many representative models.
• This motivates the study of alternative mechanisms for DM genesis.
• In the freeze-in framework, the DM is slowly populated from the thermal bath while never reaching equilibrium.