THE FeII OPTICAL EMISSION IN AGN
نویسندگان
چکیده
We investigated the FeII optical emission in a sample of about 220 low-redshift quasars and luminous Seyfert 1 galaxies. We found that a scaled and broadened FeII template based on the I Zw 1 spectrum satisfactorily reproduce the FeII emission of almost all AGN of our sample. We also confirm that FWHM of Hβ and FeIIλ4570 are tightly correlated. However, the correlation takes two slightly different forms: (a) if FWHM(Hβ) ≤ 4000 km s (Population A), the width of FeII and Hβ is statistically indistinguishable, while the FWHM(FeIIλ4570) is systematically lower than that of Hβ if FWHM(Hβ) ≥ 4000 km s (Population B). This suggests that FeII emission in Pop. B sources may come from the outer part of Hβ emitting region, where the ionization degree is lower.
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