NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Black hole accretion disks with coronaeObservations suggest the existence of both hot and cold dark matter in the centers of active galactic nuclei. Recent spectral models require a major fraction of power to be dissipated in the hot matter. We study the case when the hot matter forms a corona around a standard cold alpha-disk. In particular, we investigate the case when a major fraction, f, of the power released when the cold matter accretes is transported to and dissipated in the corona. This has major effects on the cold disk, making it colder, more geometrically thin, denser, and having larger optical depths. One important consequence is the disappearance of the effectively optically thin zone as well as of the radiation pressure dominated zone for values of f sufficiently closed to unity. The disappearance of the radiation pressure dominated zone will result in a cold disk with only a gas pressure dominated zone that is stable against thermal and viscous instabilities. We also show that the pressure ( and the radiation) from the corona will only affect the surface layers of the cold disk. Our results disagree with those of other recent work on accretion disks with coronae. We find those works to be based on unphysical assumptions.
Document ID
19950037394
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Svensson, Roland
(Stockholm Observatory Saltsjobaden, Sweden)
Zdziarski, Andrzej A.
(Nicolaus Copernicus Astronomical Center Warsaw, Poland)
Date Acquired
August 16, 2013
Publication Date
December 1, 1994
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 436
Issue: 2
ISSN: 0004-637X
Subject Category
Astronomy
Accession Number
95A68993
Funding Number(s)
CONTRACT_GRANT: NAG5-1813
CONTRACT_GRANT: NAG5-2439
CONTRACT_GRANT: KBN-221129102
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available