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arXiv · 2105.06099

Interstellar Gas Heating by Primordial Black Holes

Volodymyr Takhistov·Philip Lu·Graciela B. Gelmini·Kohei Hayashi·Yoshiyuki Inoue·Alexander Kusenko
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Abstract

Interstellar gas heating is a powerful cosmology-independent observable for exploring the parameter space of primordial black holes (PBHs) formed in the early Universe that could constitute part of the dark matter (DM). We provide a detailed analysis of the various aspects for this observable, such as PBH emission mechanisms. Using observational data from the Leo T dwarf galaxy, we constrain the PBH abundance over a broad mass-range, $M_{\rm PBH} \sim \mathcal{O}(1) M_{\odot}-10^7 M_{\odot}$, relevant for the recently detected gravitational wave signals from intermediate-mass BHs. We also consider PBH gas heating of systems with bulk relative velocity with respect to the DM, such as Galactic clouds.

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Volodymyr Takhistov, Philip Lu, Graciela B. Gelmini, Kohei Hayashi, Yoshiyuki Inoue, Alexander Kusenko. 2021-05-13. Interstellar Gas Heating by Primordial Black Holes. https://doi.org/10.1088/1475-7516%2F2022%2F03%2F017

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