Re-evaluating the resolved mass-metallicity relation with a self-consistent metallicity calibration

Abstract

Aims. The mass-metallicity relation (MZR) is essential for understanding the chemical evolution of galaxies. Whether the star formation rate (SFR) plays a role in setting the metallicity has long been debated. Using various metallicity calibrations can result in different conclusions for this fundamental yet unresolved issue. Methods. We apply a self-consistent metallicity calibration based on photoionization models to re-evaluate the resolved and integrated MZR. We utilize the integral field unit data from SDSS-IV/MaNGA, with $\sim 3.5\times10^6$ spaxels and $\sim$ 4550 galaxies. We compare our preferred metallicity calibration with several strong-line calibrations in the literature and direct method metallicity. We analyze the metallicity residual of MZR to evaluate the effects of SFR and apply the partial correlation coefficient to quantify the effects. Results. The metallicity calibration we used shows the best consistency with the direct method. We provide 3 equations for resolved MZR, and verify that local SFR does not show significant correlation with metallicity. Considering the integrated properties, (s)SFR do not present correlation with the metallicity residuals. The results suggest that an equilibrium of inflow and outflow is favored, and the mass-metallicity relation does not have a secondary dependence on SFR.