Structure of thermal pair clouds around gamma-ray-emitting black holes
- Lawrence Livermore National Laboratory, CA (USA) Stanford Univ., CA (USA)
Using certain simplifying assumptions, the general structure of a quasi-spherical thermal pair-balanced cloud surrounding an accreting black hole is derived from first principles. Pair-dominated hot solutions exist only for a restricted range of the viscosity parameter. These results are applied as examples to the 1979 HEAO 3 gamma-ray data of Cygnus X-1 and the Galactic center. Values are obtained for the viscosity parameter lying in the range of about 0.1-0.01. Since the lack of synchrotron soft photons requires the magnetic field to be typically less than 1 percent of the equipartition value, a magnetic field cannot be the main contributor to the viscous stress of the inner accretion flow, at least during the high gamma-ray states. 34 refs.
- OSTI ID:
- 5976633
- Journal Information:
- Astrophysical Journal; (USA), Vol. 367; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
BINARY STARS
GAMMA RADIATION
GALAXY NUCLEI
MILKY WAY
ACCRETION DISKS
BLACK HOLES
COSMIC GAMMA BURSTS
COSMIC X-RAY SOURCES
EMISSION SPECTRA
SPECTROSCOPY
STAR ACCRETION
VISCOSITY
COSMIC RADIATION
COSMIC RAY SOURCES
ELECTROMAGNETIC RADIATION
GALAXIES
IONIZING RADIATIONS
PRIMARY COSMIC RADIATION
RADIATIONS
SPECTRA
STAR EVOLUTION
STARS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources
640105 - Astrophysics & Cosmology- Galaxies