Self-similar accretion in thin discs around near-extremal black holes

  title={Self-similar accretion in thin discs around near-extremal black holes},
  author={G. Comp{\`e}re and R. Oliveri},
  journal={Monthly Notices of the Royal Astronomical Society},
Near-maximally spinning black holes display conformal symmetry in their near-horizon region, which is therefore the locus of critical phenomena. In this paper, we revisit the Novikov-Thorne accretion thin disk model and find a new self-similar radiation-dominated solution in the extremely high spin regime. Motivated by the self-consistency of the model, we require that matter flows at the sound speed at the innermost stable circular orbit (ISCO). We observe that, when the disk pressure is… Expand

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