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arXiv · 1804.08639

Primordial Black Hole Formation During Slow Reheating After Inflation

Bernard Carr·Konstantinos Dimopoulos·Charlotte Owen·Tommi Tenkanen
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Abstract

We study the formation of primordial black holes (PBHs) in the early Universe during a period of slow reheating after inflation. We demonstrate how the PBH formation mechanism may change even before the end of the matter-dominated phase and calculate the expected PBH mass function. We find that there is a threshold for the variance of the density contrast, $σ_c \simeq 0.05$, below which the transition occurs even before reheating, with this having important consequences for the PBH mass function. We also show that there is a maximum cut-off for the PBH mass at around $100\,M_{\odot}$, below which the subdominant radiation bath affects PBH production, making the scenario particularly interesting for the recent LIGO observations of black hole mergers.

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Bernard Carr, Konstantinos Dimopoulos, Charlotte Owen, Tommi Tenkanen. 2018-06-27. Primordial Black Hole Formation During Slow Reheating After Inflation. https://doi.org/10.1103/physrevd.97.123535

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