Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-02-17
Astrophys.J. 625 (2005) 913-922
Astronomy and Astrophysics
Astrophysics
30 pages, 11 eps figures, accepted for publication in ApJ
Scientific paper
10.1086/429884
We have calculated the structures and the emergent spectra of stationary, geometrically thin accretion disks around 100 and 1000 M_sun black holes in both the Schwarzschild and extreme Kerr metrics. Equations of radiative transfer, hydrostatic equilibrium, energy balance, ionization equilibrium, and statistical equilibrium are solved simultaneously and consistently. The six most astrophysically abundant elements (H, He, C, N, O, and Fe) are included, as well as energy transfer by Comptonization. The observed spectrum as a function of viewing angle is computed incorporating all general relativistic effects. We find that, in contrast with the predictions of the commonly-used multi-color disk (MCD) model, opacity associated with photoionization of heavy elements can significantly alter the spectrum near its peak. These ionization edges can create spectral breaks visible in the spectra of slowly-spinning black holes viewed from almost all angles and in the spectra of rapidly-spinning black holes seen approximately pole-on. For fixed mass and accretion rate relative to Eddington, both the black hole spin and the viewing angle can significantly shift the observed peak energy of the spectrum, particularly for rapid spin viewed obliquely or edge-on. We present a detailed test of the approximations made in various forms of the MCD model. Linear limb-darkening is confirmed to be a reasonable approximation for the integrated flux, but not for many specific frequencies of interest.
Hubeny Ivan
Hui Yawei
Krolik Julian H.
No associations
LandOfFree
Non-LTE Spectra of Accretion Disks Around Intermediate-Mass Black Holes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Non-LTE Spectra of Accretion Disks Around Intermediate-Mass Black Holes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-LTE Spectra of Accretion Disks Around Intermediate-Mass Black Holes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-97048