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arXiv · 1803.02745

Distribution of primordial black holes and 21cm signature

Jinn-Ouk Gong·Naoya Kitajima
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Abstract

We show that the number of primordial black holes (PBHs) which is originated from primordial density perturbations with moderately-tilted power spectrum fluctuates following the log-normal distribution, while it follows the Poisson distribution if the spectrum is steeply blue. The log-normal, as well as the Poisson, fluctuation of the PBH number behaves as an isocurvature mode and affects the matter power spectrum and the halo mass function in a different way from those for the Poisson case. The future 21cm observation can potentially put a stronger constraint on the PBH fraction than the current one in a wide mass range, $10^{-5}M_\odot$--$10M_\odot$.

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Jinn-Ouk Gong, Naoya Kitajima. 2018-08-15. Distribution of primordial black holes and 21cm signature. https://doi.org/10.1088/1475-7516%2F2018%2F11%2F041

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