New metallicity calibration for Seyfert 2 galaxies based on the N2O2 index
| Autor: | Mónica V. Cardaci, Guillermo F. Hägele, C.S. Castro, O. L. Dors |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Galaxies: general
Electron density Ciencias Astronómicas Active galactic nucleus Galaxies: abundances Metallicity Astrophysics::High Energy Astrophysical Phenomena FOS: Physical sciences abundances [Galaxies] Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Galaxies: formation 01 natural sciences Luminosity 0103 physical sciences ISM [Galaxies] Emission spectrum 010303 astronomy & astrophysics Ciencias Exactas Astrophysics::Galaxy Astrophysics Line (formation) Physics 010308 nuclear & particles physics Galaxies: evolution Astronomy Astronomy and Astrophysics general [Galaxies] evolution [Galaxies] formation [Galaxies] Astrophysics - Astrophysics of Galaxies Galaxy Galaxies: ISM Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Intensity (heat transfer) |
| Zdroj: | SEDICI (UNLP) Universidad Nacional de La Plata instacron:UNLP |
| Popis: | 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 by 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 the narrow-line regions of Seyfert 2 galaxies exhibit a large range of metallicities (0.3 ≲ Z/Z⊙ ≲ 2.0), with a median value Z ≈ Z⊙. Regarding the possible existence of correlations between the luminosity L(Hβ), the electron density and the colour excess E(B − V) with the metallicity in this kind of objects, we do not find correlations between them. Instituto de Astrofísica de La Plata Facultad de Ciencias Astronómicas y Geofísicas |
| Databáze: | OpenAIRE |
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