An alpha theory of time-dependent warped accretion discs |
| |
Authors: | G. I. Ogilvie |
| |
Affiliation: | Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Straße 1, Postfach 1523, D-85740 Garching bei München, Germany;Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA |
| |
Abstract: | The non-linear fluid dynamics of a warped accretion disc was investigated in an earlier paper by developing a theory of fully non-linear bending waves in a thin, viscous disc. That analysis is extended here to take proper account of thermal and radiative effects by solving an energy equation that includes viscous dissipation and radiative transport. The problem is reduced to simple one-dimensional evolutionary equations for mass and angular momentum, expressed in physical units and suitable for direct application. This result constitutes a logical generalization of the alpha theory of Shakura & Sunyaev to the case of a time-dependent warped accretion disc. The local thermal–viscous stability of such a disc is also investigated. |
| |
Keywords: | accretion, accretion discs hydrodynamics waves |
|
|