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BLR velocities in optically and X-ray selected AGN samples

Dieter Engels·Ralf Keil
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Abstract

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 H-beta linewidths. We find that the linewidth distribution of quasars is shifted towards higher velocities ( =4300 km s-1) compared to the distribution of Sy 1s ( =3000 km s-1). There are no Narrow Line Quasars, i.e. there are no AGNs with quasar luminosities and FWHM(H-beta) < 2000 km s-1. NLSy1s comprise 20-30 per cent of the AGN population at faint absolute magnitudes (MB>-22), irrespective of the selection method. In the RASS sample we find Gamma [0.1-2.4 keV] < 3.3. The Gamma vs. FWHM(H-beta) distribution for Sy 1 galaxies is consistent with previous work. For QSOs the spectral index also flattens with increasing FWHM(H-beta), but they have larger linewidths than Seyfert 1s.

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Dieter Engels, Ralf Keil. 2000-05-08. BLR velocities in optically and X-ray selected AGN samples. https://arxiv.org/abs/astro-ph/0005157

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