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arXiv · 2112.02534

Primordial Black Holes in Matter-Dominated Eras: the Role of Accretion

V. De Luca·G. Franciolini·A. Kehagias·P. Pani·A. Riotto
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Abstract

We consider the role of secondary infall and accretion onto an initially overdense perturbation in matter-dominated eras, like the one which is likely to follow the end of inflation. We show that primordial black holes may form through post-collapse accretion, namely the accretion onto an initial overdensity whose collapse has not given rise to a primordial black hole. Accretion may be also responsible for the growth of the primordial black hole masses by orders of magnitude till the end of the matter-dominated era.

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V. De Luca, G. Franciolini, A. Kehagias, P. Pani, A. Riotto. 2021-12-05. Primordial Black Holes in Matter-Dominated Eras: the Role of Accretion. https://doi.org/10.1016/j.physletb.2022.137265

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