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arXiv · 1009.2209

The Prevalence of Narrow Optical Fe II Emission Lines in Type 1 Active Galactic Nuclei

Xiao-Bo Dong·Luis C. Ho·Jian-Guo Wang·Ting-Gui Wang·Huiyuan Wang·Xiaohui Fan·Hongyan Zhou
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Abstract

From detailed spectral analysis of a large sample of low-redshift active galactic nuclei (AGNs) selected from the Sloan Digital Sky Survey, we demonstrate---statistically for the first time---that narrow optical Fe II emission lines, both permitted and forbidden, are prevalent in type 1 AGNs. Remarkably, these optical lines are completely absent in type 2 AGNs, across a wide luminosity range, from Seyfert 2 galaxies to type 2 quasars. We suggest that the narrow FeII-emitting gas is confined to a disk-like geometry in the innermost regions of the narrow-line region on physical scales smaller than the obscuring torus.

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Xiao-Bo Dong, Luis C. Ho, Jian-Guo Wang, Ting-Gui Wang, Huiyuan Wang, Xiaohui Fan, Hongyan Zhou. 2010-09-12. The Prevalence of Narrow Optical Fe II Emission Lines in Type 1 Active Galactic Nuclei. https://doi.org/10.1088/2041-8205%2F721%2F2%2Fl143

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