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Different Velocity Dependences of Physical Conditions of High- and Low-Ionization Lines in Broad-Line Regions

Stephanie A. Snedden·C. Martin Gaskell
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Abstract

We present results from a study of high- and low-ionization emission line ratios as a function of projected velocity for a sample of eight active galactic nuclei (AGNs). Our results are based on analysis of high signal-to-noise optical and Hubble Space Telescope (HST) UV spectra. Comparing the emission line ratios to those predicted by photoionization models indicates that the physical conditions responsible for the high-ionization emission lines are consistent with a wind, whereas those of the low-ionization lines are consistent with a virialized disk.

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Stephanie A. Snedden, C. Martin Gaskell. 2004-03-08. Different Velocity Dependences of Physical Conditions of High- and Low-Ionization Lines in Broad-Line Regions. https://arxiv.org/abs/astro-ph/0403174

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