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arXiv · 2109.12824

Primordial Black Holes from CDM Isocurvature Perturbations

Samuel Passaglia·Misao Sasaki
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Abstract

We show that primordial black holes can be produced from the collapse of large isocurvature perturbations of the cold dark matter. We develop a novel procedure to compute the resulting black hole abundance by studying matched perturbations of matter-only universes, and we use our procedure to translate observational constraints on black hole abundances into model-independent constraints on cold dark matter isocurvature perturbations over a wide range of scales. The constraint on the typical amplitude of the primordial perturbations weakens slightly slower than linearly on small scales.

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Samuel Passaglia, Misao Sasaki. 2021-09-27. Primordial Black Holes from CDM Isocurvature Perturbations. https://doi.org/10.1103/physrevd.105.103530

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