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Reionization of the Universe induced by Primordial Black Holes

Marina Gibilisco
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Abstract

In this paper I will discuss the possibility of a reionization of the Universe due to the photons emitted by evaporating primordial black holes (PBHs); this process should happen during the last stages of the PBHs life, when the particle emission is very intense. I will study the time evolution of the ionization degree x, of the plasma temperature $T_{e}$ and of the photon number density $n_γ$ characterizing the Universe after the recombination epoch: a system of coupled differential equations for these variables is solved in an analytical way by assuming, as a photon source, PBHs having an initial mass $M\sim 10^{14}$ g. The results I obtain prove that such a kind of reionization is possible, being able to increase the ionization degree of the Universe from a value x=0.002 (just after the recombination) to values near 1 (when the black holes evaporation ends).

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Marina Gibilisco. 1996-11-27. Reionization of the Universe induced by Primordial Black Holes. https://doi.org/10.1142/s0217751x96002546

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