Selfsimilar secondary infall and accretion in an Einsteinde Sitter universe
Abstract
Similarity solutions are given for secondary infall onto an accreting center in an Einsteinde Sitter universe. The case of a central black hole quietly accreting all the infalling gas is considered first. If there is no central black hole and the gas is collisional, a shock forms and propagates outward; similarity solutions are given for the adiabatic postshock flow. Solutions for collisionless fluid shells and for a collisional fluid with omega much less than one moving in the potential of the omega = 1 collisionless solution are presented. A comparison is made with similarity solutions found recently for expanding voids by Bertschinger (1985), and it is shown how the collisionless similarity solutions can be used to infer the ages of objects formed by secondary infall.
 Publication:

The Astrophysical Journal Supplement Series
 Pub Date:
 May 1985
 DOI:
 10.1086/191028
 Bibcode:
 1985ApJS...58...39B
 Keywords:

 Accretion Disks;
 Black Holes (Astronomy);
 Cosmology;
 Galactic Clusters;
 Galactic Evolution;
 Hydrodynamics;
 Relativity;
 Collisional Plasmas;
 Collisionless Plasmas;
 Density Distribution;
 Galactic Structure;
 Gravitational Collapse;
 Perturbation Theory;
 Shock Wave Propagation;
 Similarity Theorem;
 Astrophysics