Sensitivity of primordial black hole abundance on the reheating phase

TL;DR

This paper explores how the reheating phase after inflation significantly affects the predicted abundance and mass distribution of primordial black holes, introducing substantial uncertainties in their role as dark matter.

Contribution

It demonstrates the impact of reheating parameters on PBH abundance and mass spectrum within a specific inflationary model, highlighting the sensitivity of PBH predictions.

Findings

Reheating parameters can alter PBH abundance by several orders of magnitude.

The peak position and amplitude of PBH mass fraction are highly sensitive to reheating details.

Reheating introduces significant uncertainties in PBH-based dark matter scenarios.

Abstract

We investigate the sensitivity of reheating history on the abundance of primordial black holes (PBHs). Contrary to the monochromatic case of mass fraction of PBH, reheating era with different e-folding and equation-of-state can have a substantial impact on the abundance of PBH with an extended mass fraction. We demonstrate explicitly this reheating sensitivity in an illustrative model of single field inflation with a quasi-inflection point, and find that both the peak position and amplitude of the extended mass fraction as well as the abundance of PBH in DM can vary by many orders of magnitude, which adds another layer of uncertainty on the PBH scenarios as dark matter.