Freeze-in and Freeze-out in Right-Handed Neutrino Extended MSSM with Seesaw
Authors
Tushar Gupta
Matti Heikinheimo
Katri Huitu
Harri Waltari
Abstract
We investigate the possibility of saturating the relic density bound with light higgsinos. When the minimal supersymmetric Standard Model is extended with right-handed neutrino superfields and the seesaw scale is very low, right-handed sneutrinos can be produced via the freeze-in mechanism. In such a case we can have essentially two independent sources for dark matter, the traditional freeze-out of higgsinos and the freeze-in of right-handed sneutrinos. The heavier of these two will decay to the lighter species with a delay. We rule out such a scenario for all seesaw models as the lifetime of sterile neutrinos, produced over-abundantly via Dodelson-Widrow mechanism, exceeds the age of the universe and will contribute to the relic density.
