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, selfsimilar flows containing two or more spiral shaped shock waves. They represent shocks initiated by a disturbance at the outer edge of the disk. Selfsimilar 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:

 Accretion Disks;
 Magnetohydrodynamics;
 Shock Waves;
 Computational Astrophysics;
 Roche Limit;
 Astrophysics