A full relativistic thin disc – the physics of the plunging region and the value of the stress at the ISCO

  title={A full relativistic thin disc – the physics of the plunging region and the value of the stress at the ISCO},
  author={William J Potter},
The widely used Novikov-Thorne relativistic thin disc equations are only valid down to the radius of the innermost stable circular orbit (ISCO). This leads to an undetermined boundary condition at the ISCO, known as the inner stress of the disc, which sets the luminosity of the disc at the ISCO and introduces considerable ambiguity in accurately determining the mass, spin and accretion rate of black holes from observed spectra. We resolve this ambiguity by self-consistently extending the… 
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