New X-ray bound on density of primordial black holes

Yoshiyuki Inoue; Alexander Kusenko

doi:10.1088/1475-7516/2017/10/034

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arXiv · 1705.00791

New X-ray bound on density of primordial black holes

Yoshiyuki Inoue·Alexander Kusenko

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Abstract

We set a new upper limit on the abundance of primordial black holes (PBH) based on existing X-ray data. PBH interactions with interstellar medium should result in significant fluxes of X-ray photons, which would contribute to the observed number density of compact X-ray objects in galaxies. The data constrain PBH number density in the mass range from a few $M_\odot$ to $2\times 10^7 M_\odot$. PBH density needed to account for the origin of black holes detected by LIGO is marginally allowed.

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Yoshiyuki Inoue, Alexander Kusenko. 2017-05-02. New X-ray bound on density of primordial black holes. https://doi.org/10.1088/1475-7516%2F2017%2F10%2F034

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