HEP Theory Journal Club

Relativistic treatment of dark thermalization

Takashi Toma

McGill

If dark sector is decoupled from the Standard Model sector, these two sectors may separately be thermalized with different temperatures. In this case, the Maxwell-Boltzmann distribution is traditionally assumed for dark sector regardless of the temperature for simplicity. In this talk, the full Bose-Einstein distribution is considered in the simplest model of real scalar dark matter. We find that the resultant reaction rates are enhanced compared to the rates with the Maxwell-Boltzmann distribution at high temperature. This affects on calculations of relic abundance of dark matter at relativistic regime. We also consider applications of our formalism to the freeze-in mechanism.