Emission-line Trends With Fe II Strength In AGN
Abstract
Active galactic nuclei (AGN) have Fe II emission from the broad line region (BLR) that differs greatly in strength from object to object. Using AGN spectra from the Sloan Digital Sky Survey (SDSS), we measure trends in the emission-line ratios of the narrow line region (NLR) as a function of Fe II strength. The Fe/Ne abundance ratio shows no significant variation, but the N/S ratio increases by a factor of 2 with increasing Fe II strength. Because nitrogen is a secondary element in galactic chemical evolution, this in turn may indicate a trend in the overall metallicity of the NLR gas with increasing Fe II strength. We discuss factors that may contribute to the wide range of Fe II strength in AGN.
- Publication:
-
American Astronomical Society Meeting Abstracts #216
- Pub Date:
- May 2010
- Bibcode:
- 2010AAS...21630405S