Open AccessAn alpha theory of time‐dependent warped accretion discs
Author(s) -
Ogilvie G. I.
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03654.x
Subject(s) - physics , accretion (finance) , radiative transfer , angular momentum , classical mechanics , accretion disc , mechanics , dissipation , astrophysics , quantum mechanics
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.