Publication date: Dec 2004
Abstract:
We consider basic properties of both the geometrically thin and thick
accretion disks in the Kerr-de Sitter black-hole and naked-singularity
spacetimes. The properties are determined by character of the equatorial
circular geodesics of these spacetimes and by the equilibrium
configurations of a perfect fluid rotating around their symmetry axis.
Transformation of a Kerr-de Sitter naked singularity into an extreme
black hole due to accretion in the thin disks is briefly discussed for
both the plus-family and minus-family disks. It is shown that such a
conversion leads to an abrupt instability of the innermost parts of the
plus-family accretion disks that can have strong observational
consequences.
Authors:
Stuchlík, Zdeněk; Slaný, Petr;