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arXiv · 2205.15277

Micro-Bose/Proca dark matter stars from black hole superradiance

Abstract

We study the production of heavy, $\mu \gtrsim 1$ TeV, bosonic spin $s=0,1$ dark matter (DM) via the simultaneous processes of Hawking evaporation and superradiance (SR) from an initial population of small, $\lesssim 10^6$ kg, primordial black holes (PBHs). Even for small initial PBH spins the SR process can produce extremely dense gravitationally-bound DM Bose or Proca soliton "stars" of radius $\lesssim {\rm pm}$ and mass $\sim 10^{\rm few}$ kg that can survive to today, well after PBH decay. These solitons can constitute a significant fraction of the DM density, rising to $\gtrsim 50\%$ in the vector DM case.

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BibTeXRIS

John March-Russell, João G. Rosa. 2022-05-30. Micro-Bose/Proca dark matter stars from black hole superradiance. https://arxiv.org/abs/2205.15277

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