More fundamental than the fundamental metallicity relation - The effect of the stellar metallicity on the gas-phase mass-metallicity and gravitational potential-metallicity relations Sánchez Menguiano, Laura Sánchez Sánchez, Sebastián F. Sánchez Almeida, Jorge Muñoz Tuñón, Casiana Techniques: imaging spectroscopy Galaxies: abundances Galaxies: evolution Context. One of the most fundamental scaling relations in galaxies is observed between metallicity and stellar mass – the massmetallicity relation (MZR) – although recently a stronger dependence of the gas-phase metallicity with the galactic gravitational potential (ΦZR) has been reported. Further dependences of metallicity on other galaxy properties have been revealed, with the star formation rate (SFR) being one of the most studied and debated secondary parameters in the relation (the so-called fundamental metallicity relation). Aims. In this work we explore the dependence of the gas-phase metallicity residuals from the MZR and ΦZR on different galaxy properties in the search for the most fundamental scaling relation in galaxies. Methods. We applied a random forest regressor algorithm on a sample of 3430 nearby star-forming galaxies from the SDSS-IV MaNGA survey. Using this technique, we explored the effect of 147 additional parameters on the global oxygen abundance residuals obtained after subtracting the MZR. Alternatively, we followed a similar approach with the metallicity residuals from the ΦZR. Results. The stellar metallicity of the galaxy is revealed as the secondary parameter in both the MZR and the ΦZR, ahead of the SFR. This parameter reduces the scatter in the relations ~10-15%. We find the 3D relation between gravitational potential, gas metallicity, and stellar metallicity to be the most fundamental metallicity relation observed in galaxies. 2024-06-18T09:58:57Z 2024-06-18T09:58:57Z 2024-02-09 journal article Laura Sánchez-Menguiano, Sebastián F. Sánchez, Jorge Sánchez Almeida and Casiana Muñoz-Tuñón. More fundamental than the fundamental metallicity relation - The effect of the stellar metallicity on the gas-phase mass-metallicity and gravitational potential-metallicity relations. A&A, 682 (2024) L11 DOI: https://doi.org/10.1051/0004-6361/202348423 https://hdl.handle.net/10481/92665 10.1051/0004-6361/202348423 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional EDP Sciences