Primordial black hole reheating
Md Riajul Haque, Essodjolo Kpatcha, Debaprasad Maity, Yann Mambrini
Abstract
The postinflationary reheating phase is usually said to be solely governed by the decay of coherently oscillating inflatons into radiation. In this submission, we explore a new avenue towards reheating through the evaporation of primordial black holes (PBHs). After the inflation, if PBHs form, depending on its initial mass, abundance, and inflaton coupling with the radiation, we found two physically distinct possibilities of reheating the Universe. In one possibility, the thermal bath is solely obtained from the decay of PBHs while inflaton plays the role of the dominant energy component in the entire process. In the other possibility, we found that PBHs dominate the total energy budget of the Universe during the course of evolution, and then its subsequent evaporation leads to a radiation dominated universe. Furthermore, we analyze the impact of both monochromatic and extended PBH mass functions and estimate the detailed parameter ranges for which those distinct reheating histories are realized.