Low scale leptogenesis and dark matter in the presence of primordial
  black holes
  We study the possibility of low scale leptogenesis along with dark matter
(DM) in the presence of primordial black holes (PBH). For a common setup to
study both leptogenesis and DM we consider the minimal scotogenic model which
also explains light neutrino mass at radiative level. While PBH in the mass
range of $0.1-10^5$ g can, in principle, affect leptogenesis, the required
initial PBH fraction usually leads to overproduction of scalar doublet DM whose
thermal freeze-out occurs before PBH evaporation. PBH can lead to non-thermal
source of leptogenesis as well as dilution of thermally generated lepton
asymmetry via entropy injection, with the latter being dominant. The parameter
space of scotogenic model which leads to overproduction of baryon or lepton
asymmetry in standard cosmology can be made consistent in the presence of PBH
with appropriate initial mass and energy fraction. On the other hand, for such
PBH parameters, the scalar DM is constrained to be in light mass regime where
its freeze-out occurs after PBH evaporation. We then discuss the possibility of
fermion singlet DM with $N_2$ leptogenesis in the same model where due to
singlet nature of DM, its connection with PBH parameters and hence leptogenesis
becomes stronger compared to the previous case.
