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The FeII Optical Emission in AGN

C. Bongardo·R. Zamanov·P. Marziani·M. Calvani·J. W. Sulentic
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Abstract

We investigated the optical FeII emission in a sample of about 215 low-redshift AGN (quasars and luminous Seyfert 1 galaxies). We find that a scaled and broadened FeII template based on the I Zw 1 spectrum can satisfactorily model the FeII emission in almost all sources in our sample. We confirm that FWHM H$β$ and FeII$λ$4570 are strongly correlated. The correlation is different for sources with FWHM(H$β$) greater than or less than $\sim$4000 km s$^{-1}$. Sources with FWHM H$β$$\leq$ 4000 km s$^{-1}$ (Population A) show no difference between FWHM H$β$ and FeII while sources with FWHM(H$β$) $\geq$ 4000 km s$^{-1}$ (Population B) show FWHM FeII that is systematically smaller than FWHM H$β$. This may be telling us that FeII emission in Pop. B sources comes from only the outermost part of the H$β$\ emitting region where the degree of ionization is lowest.

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C. Bongardo, R. Zamanov, P. Marziani, M. Calvani, J. W. Sulentic. 2002-11-27. The FeII Optical Emission in AGN. https://arxiv.org/abs/astro-ph/0211418

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