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arXiv · 2303.17601

Gravitational wave microlensing by dressed primordial black holes

Juan Urrutia·Ville Vaskonen·Hardi Veermäe
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Abstract

We study gravitational wave microlensing by primordial black holes (PBHs), accounting for the effect of a particle dark matter minihalo surrounding them. Such minihaloes are expected when PBHs make up only a fraction of all dark matter. We find that the LIGO-Virgo detections imply a $1\sigma$ bound on the abundance of PBHs heavier than $50 M_{\odot}$. The next generation observatories can potentially probe PBHs as light as $0.01 M_\odot$ and down to $2\times10^{-4}$ fraction of all dark matter. We also show that these detectors can distinguish between dressed and naked PBHs, providing a novel way to study the distribution of particle dark matter around black holes and potentially shed light on the origins of black holes.

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Juan Urrutia, Ville Vaskonen, Hardi Veermäe. 2023-03-30. Gravitational wave microlensing by dressed primordial black holes. https://doi.org/10.1103/physrevd.108.023507

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