Stationary shocks in accretion disks
Abstract
Special solutions of the equations of motion and continuity near the midplane of a thin accretion disk are obtained by analytic and numerical means. They have the form of stationary, self-similar flows containing two or more spiral shaped shock waves. They represent shocks initiated by a disturbance at the outer edge of the disk. Self-similar shocks excited at the center of the disk do not seem to exist. No solutions were found containing only one shock. Adiabatically accreting solutions exist in which there is a unique relation between the ratio of specific heats γ and the opening angle of the shock. When radiative losses from the disk are included, solutions exist for γ above a certain minimum value. The strength of the shock decreases with decreasing disk thickness. An effective "α parameter" can be defined, it varies with disk thickness like (h/r)1.5. An analogy between the present problem and the case of spherically symmetric accretion is discussed.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1987
- Bibcode:
- 1987A&A...184..173S
- Keywords:
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- Accretion Disks;
- Magnetohydrodynamics;
- Shock Waves;
- Computational Astrophysics;
- Roche Limit;
- Astrophysics