All-Moscow Seminar of Astrophysicists
(ASA)

The seminar is supported by the grant of Federal Programm "Integration"
annotation of talk
Andrei Gruzinov (Inst. of Adv. Studies, Princeton, USA
Collisionless Halos Around Black Holes


When a black hole accretes slowly, the radiative cooling of the infalling gas is weak and the accretion disk does not form. A hot collisionless quasi-spherical halo is formed instead. The properties of such halos are discussed. The rate of accretion, the radiative efficiency, and the temperature and density near the hole are evaluated.