Open AccessVertical structure of accretion discs with hot coronae in active galactic nuclei
Author(s) -
Różańska A.,
Czerny B.,
Życki P. T.,
Pojmański G.
Publication year - 1999
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1999.02425.x
Subject(s) - physics , opacity , astrophysics , corona (planetary geology) , reflection (computer programming) , active galactic nucleus , astronomy , accretion (finance) , accretion disc , convection , ionization , galaxy , optics , mechanics , astrobiology , ion , computer science , venus , programming language , quantum mechanics
ABSTRACT We study the vertical structure of a radiation‐pressure‐dominated disc with a hot corona. We include all the relevant processes like bound–free opacity and convection. We show that the presence of the corona modifies considerably the density and the opacity of the disc surface layers, which are important from the point of view of spectrum formation. The surface of the disc with a corona is much denser and less ionized than the surface of a bare disc. Such a disc is likely to produce a neutral reflection and a local spectrum close to a blackbody. This effect will help to reconcile the predictions of accretion disc models with the observational data since a neutral reflection and a lack of Lyman edge are generally seen in active galactic nuclei.