view Abstract Citations (35) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Black hole accretion disks - Coronal stabilization of the Lightman-Eardley instability Ionson, J. A. ; Kuperus, M. Abstract Physical processes by which the presence of a corona around a black hole can raise the threshold of onset of the Lightman-Eardley (L-E, 1976) instability are explored analytically. The L-E model predicts that an optically thick disk becomes unstable when the disk radiation pressure exceeds the disk gas pressure. The model has important implications for the validity of either the coronal disk or two-temperature disk models for accretion zones around black holes. It is shown that a corona can dissipate accreting gravitational energy through radiative cooling. Specific ratios of hard/soft X-rays are quantified for stable and unstable conditions. X-ray spectra from Cyg X-1 are cited as residing below the instability threshold value and thus are supportive of the coronal disk model. Publication: The Astrophysical Journal Pub Date: September 1984 DOI: 10.1086/162418 Bibcode: 1984ApJ...284..389I Keywords: Accretion Disks; Astronomical Models; Black Holes (Astronomy); Magnetohydrodynamic Stability; Stellar Coronas; Stellar Gravitation; Energy Dissipation; Radiant Cooling; Stellar Mass Accretion; X Ray Spectra; Astrophysics full text sources ADS |