Primordial black holes and mirror dark matter

Abstract: If mirror matter exists but cannot comprise all of the dark matter (DM) in the universe, we can expect that the additional DM component may only interact with the other sectors gravitationally. One of the natural candidate of a gravitationally interacting component is a primordial black hole (PBH). Therefore, if mirror matter exists but cannot comprise all of the DM in the universe, the existence of PBH may be expected as a candidate of the additional DM component. In this case, the remaining DM components may be PBHs or $SU(3)\times SU(2)\times U(1)$ singlet particles from PBH. We show constraints on PBH with the mirror DM. Particularly, the initial PBH mass is estimated to be $10^{17} \ {\rm g} \lesssim M_{\rm PBH} \lesssim 10^{23} \ {\rm g}$, if the DM comprises mirror baryons and PBHs.