Dark Matter from Exponential Growth

We propose a novel mechanism for the production of dark matter (DM) from a thermal bath based on the idea that DM particles x can transform heat bath particles yr: xyr -> xx. For a small initial abundance ofx, this leads to an exponential growth of the DM number density in close analogy to other familiar exponential growth processes in nature. We demonstrate that this mechanism complements freeze-in and freeze-out production in a generic way, opening new parameter space to explain the observed DM abundance, and we discuss observational prospects for such scenarios.

Automated summary

The proposed mechanism offers a new approach to explain the production of dark matter from a thermal bath, complementing existing production mechanisms. By doing so, it opens up new parameter space for explaining the observed dark matter abundance.