Abstract The non-observation of extragalactic Hawking radiation from primordial black holes of 1016 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.

中文翻译：

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X射线和伽马射线对霍金辐射原始黑洞丰度的限制

摘要 未观测到来自 1016 g 原始黑洞的河外霍金辐射为其宇宙丰度设定了一个保守的强界限。我们重新审视了这个界限，并展示了如何通过对 MeV 范围内的 AGN 和耀变体发射组合进行充分建模来改进它（在质量范围和强度方面）。我们还估计了未来 X 射线实验对原始黑洞丰度的敏感性，该实验能够识别大量天体物理源，有助于该能量范围内的漫射背景。