Chemical abundance of LINER galaxies metallicity calibrations based on SDSS-IV MaNGA

Oliveira Jr, C. B.; Krabbe, A. C.; Hernandez-Jimenez, J. A.; Dors Jr, O. L.; Zinchenko, I. A.; Haegele, G. F.; Cardaci, M. V. und Monteiro, A. F. (2022): Chemical abundance of LINER galaxies metallicity calibrations based on SDSS-IV MaNGA. In: Monthly Notices of the Royal Astronomical Society, Bd. 515, Nr. 4: S. 6093-6108

Abstract

The ionizing source of Low Ionization Nuclear Emission Regions (LINERs) is uncertain. Because of this, an empirical relation to determine the chemical abundances of these objects has not been proposed. In this work, for the first time, we derived two semi-empirical calibrations based on photoionization models to estimate the oxygen abundance of LINERS as a function of the N2 and O3N2 emission-line intensity ratios. These relations were calibrated using oxygen abundance estimations obtained by comparing the observational emission-line ratios of 43 LINER galaxies (taken from the MaNGA survey) and grids of photoionization models built with the CLOUDY code assuming post-Asymptotic Giant Branch (post-AGB) stars with different temperatures. We found that the oxygen abundance of LINERs in our sample is in the 8.48 less than or similar to 12 +log(O/H)less than or similar to 8.84 range, with a mean value of 12 + log(O/H)=8.65. We recommend the use of the N2 index to estimate the oxygen abundances of LINERs, since the calibration with this index presented a much smaller dispersion than the O3N2 index. In addition, the estimated metallicities are in good agreement with those derived by extrapolating the disk oxygen abundance gradients to the centre of the galaxies showing that the assumptions of the models are suitable for LINERs. We also obtained a calibration between the logarithm of the ionization parameter and the [OIII]/[OII] emission-line ratio.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 0035-8711
• Sprache: Englisch