Freeze-in from preheating

We consider the production of dark matter during the process of reheating after inflation. The relic density of dark matter from freeze-in depends on both the energy density and energy distribution of the inflaton scattering or decay products composing the radiation bath. We compare the perturbative and non-perturbative calculations of the energy density in radiation. We also consider the (likely) possibility that the final state scalar products are unstable. Assuming either thermal or non-thermal energy distribution functions, we compare the resulting relic density based on these different approaches. We show that the present-day cold dark matter density can be obtained through freeze-in from preheating for a large range of dark matter masses.

Automated summary

This article investigates the production of dark matter during the process of reheating after inflation. By comparing perturbative and non-perturbative calculations of energy density and considering the instability of final state scalar products, the resulting relic density based on different approaches is compared. It is shown that the present-day cold dark matter density can be obtained through freeze-in from preheating for a large range of dark matter masses.