BLR velocities in optically and X - ray selected AGN samples
نویسنده
چکیده
We have analyzed optical spectra of 473 X-ray and 235 optically selected AGNs, to study their emission line properties. We present results of an analysis of the Hβ linewidths. We find that the linewidth distribution of quasars is shifted towards higher velocities (=4300 km s) compared to the distribution of Sy 1s (=3000 km s). There are no Narrow Line Quasars, i.e. there are no AGNs with quasar luminosities and FWHM(Hβ)<2000 km s . NLSy1s comprise 20–30% of the AGN population at faint absolute magnitudes (MB> −22), irrespective of the selection method. In the RASS sample we find Γ [0.1-2.4 keV] <3.3. The Γ vs. FWHM(Hβ) distribution for Sy 1 galaxies is consistent with previous work. For QSOs the spectral index also flattens with increasing FWHM(Hβ), but they have larger linewidths than Seyfert 1s.
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