Artigo Acesso aberto Produção Nacional Revisado por pares

Gas-phase metallicity determinations in nearby AGNs with SDSS-IV MaNGA: evidence of metal-poor accretion

2022; Oxford University Press; Volume: 513; Issue: 1 Linguagem: Inglês

10.1093/mnras/stac771

ISSN

1365-2966

Autores

Janaina Correa do Nascimento, O. L. Dors, Thaisa Storchi‐Bergmann, Nícolas D Mallmann, Rogério Riffel, Gabriele S Ilha, Rogemar A. Riffel, Sandro B. Rembold, Alice Deconto Machado, L. N. da Costa, Mark Armah,

Tópico(s)

Astronomy and Astrophysical Research

Resumo

We derive the metallicity (traced by the O/H abundance) of the Narrow Line Region ( NLR) of 108 Seyfert galaxies as well as radial metallicity gradients along their galaxy disks and of these of a matched control sample of no active galaxies. In view of that, observational data from the SDSS-IV MaNGA survey and strong emission-line calibrations taken from the literature were considered. The metallicity obtained for the NLRs %each Active Galactic Nucleus (AGN) was compared to the value derived from the extrapolation of the radial oxygen abundance gradient, obtained from \ion{H}{ii} region estimates along the galaxy disk, to the central part of the host galaxies. We find that, for most of the objects ($\sim 80\,\%$), the NLR metallicity is lower than the extrapolated value, with the average difference ($ $) between these estimates ranging from 0.16 to 0.30 dex. We suggest that $ $ is due to the accretion of metal-poor gas to the AGN that feeds the nuclear supermassive black hole (SMBH), which is drawn from a reservoir molecular and/or neutral hydrogen around the SMBH. Additionally, we look for correlations between $D$ and the electron density ($N_{\rm e}$), [\ion{O}{iii}]$\lambda$5007 and H$\alpha$ luminosities, extinction coefficient ($A_{V})$ of the NLRs, as well as the stellar mass ($M_{*}$) of the host galaxies. Evidences of an inverse correlation between the $D$ and the parameters $N_{\rm e}$, $M_{*}$ and $A_{\rm v}$ were found.

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