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

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