New metallicity calibration for Seyfert 2 galaxies based on the N2O2 index

CASTRO, C.S.; DORS, O.L.; CARDACI, M.V.; HÄGELE, G.F.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2017

0035-8711

We derive a new relation between the metallicity of Seyfert 2 Active Galactic Nuclei (AGNs) and the intensity of the narrow emission-lines ratio N2O2=log([N II]λ6584/[O II]λ3727). The calibration of this relation was performed determining the metallicity (Z) of a sample of 58 AGNs through a diagram containing the observational data and the results of a grid of photoionization models obtained with the Cloudy code. We find the new Z/Z⊙-N2O2 relation using the obtained metallicity values and the corresponding observational emission line intensities for each object of the sample. Estimations derived through the use of this new calibration indicate that narrow line regions of Seyfert 2 galaxies exhibit a large range of metallicities (0.3