Astronomy and Astrophysics, volume 549A, 100-100 (2013/1-1)
The shape of broad-line profiles in active galactic nuclei.
KOLLATSCHNY W. and ZETZL M.
Abstract (from CDS):
We present a study of the broad optical/UV emission line profiles in active galactic nuclei (AGN) to get information on the dominant velocity components (turbulence, rotation, etc.) in the central broad-line region (BLR). We introduce line broadening simulations of emission line profiles and compare these results with the largest homogeneous data set of reverberation-mapped AGN. The underlying broad-line profiles in AGN are Lorentzian profiles caused by turbulence in the line emitting region. The turbulent velocities are different for the different line emitting regions of Hγ, Hα, Lyα, CIII]λ1909, HeIIλ1640, and SiIVλ1400. The turbulent velocities go from 400km/s for Hβ up to 3800km/s for Lyα+NVλ1240. The dominating broadening mechanism of these profiles is broadening due to rotation. The rotation velocities causing the line profile broadening go from 500km/s up to 6500km/s. Here we present interrelations between observed emission line widths (FWHM) and their related rotational velocities to correct for the contribution of the turbulence to the broad-line profiles.