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arXiv · 2103.12354

The evaporating primordial black hole fraction in cool-core galaxy clusters

Chak Man Lee·Man Ho Chan
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Abstract

Recent studies of gamma-ray, cosmic-ray and radio data put stringent constraints on the fraction of primordial black holes (PBHs) in our universe. In this article, we propose a new indirect method in using the X-ray luminosity data of cool-core clusters to constrain the evaporating PBH fraction for the monochromatic, log-normal and power-law mass distributions. The present results show that the amount of evaporating PBHs only constitutes a minor component of dark matter for a large parameter space. The constraints are consistent with and close to that obtained from other cosmic-ray and multi-wavelength observations.

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Chak Man Lee, Man Ho Chan. 2021-03-23. The evaporating primordial black hole fraction in cool-core galaxy clusters. https://doi.org/10.3847/1538-4357%2Fabee72

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