Disk accretion onto a black hole at subcritical luminosity

Technical Report · Thu Jan 01 04:00:00 EST 1976

OSTI ID:7212762

Bisnovatyi-kogan, G S; Blinnikov, S I

The influence of radiation pressure on the structure of accretion disk is considered when the total luminosity L approaches the Eddington limit L/sub c/. The motion of particles in the disk radiation field and gravitational field of a nonrotating black hole was investigated. It is shown that the disk accretion is destroyed when L approximately equals (0.6 + 1.0)L/sub c/. Matter outflow from the central parts of the disk to infinity then sets in. It is concluded that the luminosity cannot significantly exceed the Eddington limit. It is shown that for L greater than or approximately equal to 0.1 L/sub c/ the plasma in upper layers of the central region of the disk is heated up to temperatures approximately 10/sup 9/ K, and the disk becomes thicker as compared with the standard theory. The radiative force can generate magnetic fields B approximately 100 Gs. Convection is the main energy transfer mechanism along Z-coordinate in the central parts of the disk. The convection generates an acoustic flux which dissipates in the upper, optically thin layers of the disk and heats them. The comptonization of soft photons going from lower layers to the hot upper layers and variable accretion rate may explain the spectrum and variations of X-ray emission of the Cyg X-1.

• Research Organization: AN SSSR, Moscow. Inst. Kosmicheskikh Issledovanij
• OSTI ID: 7212762
• Report Number(s): N-77-13942; PR-271
• Country of Publication: United States
• Language: English

Related Subjects

640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BLACK HOLES
CONVECTION
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ENERGY TRANSFER
GRAVITATIONAL FIELDS
HEAT TRANSFER
HEATING
LUMINOSITY
MOTION
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATION PRESSURE
SPECTRA
STAR ACCRETION
STAR EVOLUTION
X-RAY SPECTRA