# X-ray and gamma-ray limits on the primordial black hole abundance from Hawking radiation

## TL;DR

This paper refines constraints on primordial black hole abundance by modeling astrophysical backgrounds more accurately and assesses future X-ray experiments' potential to improve these bounds.

## Contribution

It introduces an improved modeling approach for astrophysical backgrounds and evaluates future X-ray experiments' sensitivity to primordial black holes.

## Key findings

- Stronger bounds on primordial black hole abundance are obtained.
- Modeling astrophysical sources reduces uncertainties in Hawking radiation limits.
- Future X-ray missions could significantly enhance detection sensitivity.

## Abstract

The non-observation of Hawking radiation from primordial black holes of $10^{16}$g sets a conservative strong bound on their cosmological abundance. We revisit this bound and show how it can be improved (both in mass reach and strength) by an adequate modeling of the combined AGN and blazar emission in the MeV range. We also estimate the sensitivity to the primordial black hole abundance of a future X-ray experiment capable of identifying a significantly larger number of astrophysical sources contributing to the diffuse background in this energy range.