Astronomy and Astrophysics – Astrophysics
Scientific paper
Mar 1996
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996ap%26ss.237..207g&link_type=abstract
Astrophysics and Space Science, Volume 237, Issue 1-2, pp. 207-240
Astronomy and Astrophysics
Astrophysics
4
Scientific paper
Coordinated observations of variability of the continuum and the emission-line luminosities (reverberation mapping) in AGNs and quasars have fundamentally altered our understanding of the broad-line regions in active galaxies. The constraints these observations impose on the models of the BLRs have been demonstrated here by an attempt to model the BLR of NGC5548, the most intensively monitored AGN. Two models of a BLR, with one having a power law radial distribution of density and the other a gaussian radial distribution, are described and the modelled line luminosities and centroid of the line response functions are presented. A self-consistent model is presented for the change in the Civ/Lyα ratio as the continuum luminosity changes. It is shown that BLR gas must be composed of a mixture of optically thin and optically thick gas and the proportion of thick and thin gas alters with the luminosity of the ionizing continuum. The observed centroid or the lag of a line, can be a function of the continuum luminosity. The variability of the profile of the Civ line in the spectrum of NGC5548 is investigated. This profile is extremely robust and is not significantly affected by changes in the ionizing continuum. Future models of the kinematics of the BLR clouds will have to be based on very stable cloud motions and include anisotropic line emission.
Goad Michael R.
Gondhalekar P. M.
O'Brien Thomas P.
No associations
LandOfFree
The Broad Emission Line Region in AGNs and Quasars: The Impact of Variability Studies 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 The Broad Emission Line Region in AGNs and Quasars: The Impact of Variability Studies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Broad Emission Line Region in AGNs and Quasars: The Impact of Variability Studies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1643575