The dynamics of the broad-line-emitting regions of active galactic nuclei and quasars. I. Broad-line profiles.
Abstract
The line profiles resulting from various kinematical and dynamical models for the broad-line-emitting gas in Seyfert 1 galaxies and quasars are calculated. It is shown that profiles resulting from spherical systems in radial motion, for several different cases of acceleration and optical thickness to the ionizing continuum, are logarithmic, in substantial agreement with the observed line profiles for such objects. One cannot distinguish between radial flow models based upon the logarithmic shape alone. Models with rotation and/or expansion confined to a disk seem to be excluded on the basis of observed profile shapes. A reasonable ballistic model predicts line profiles given by the first exponential integral. This is logarithmic for wavelengths not too far from line center, and the dependence in the wings, when compared with observed broad-line profiles, indicates that such a form may be the most appropriate profile function.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1980
- DOI:
- 10.1086/158404
- Bibcode:
- 1980ApJ...241..903C
- Keywords:
-
- Active Galactic Nuclei;
- Line Spectra;
- Quasars;
- Spectral Line Width;
- Emission Spectra;
- Seyfert Galaxies;
- Astrophysics