William M. Baker (Univ. Cambridge)

The Fundamental Metallicity Relation (FMR) describes how gas-phase metallicity is observed to primarily depend on stellar mass, whilst having a secondary inverse dependence on star formation rate. However, the metallicity may depend (both theoretically and observationally) on several other galactic quantities, which are directly or indirectly connected with the mass, SFR and metallicity. Therefore, identifying the quantities that are directly driving the metallicity from those that related to the metallicity via secondary correlations with other quantities is difficult, but it is also important to infer from these relations the galaxy evolutionary processes that they might trace. Determining galactic properties that are primary drivers of the galaxy metallicity provides a test to both observations and simulations. In this presentation I will analyse spatially resolved observational data obtained from the MaNGA and ALMaQUEST surveys and apply partial correlation coefficients and random forest regression to untangle the intrinsic dependencies of the resolved metallicity. I will show that, based on these analyses, the local metallicity depends not only on local properties (e.g. local stellar mass surface density, galactocentric radius) but also has a fundamental dependence on global properties (total stellar mass, global SFR). I will quantify these intrinsic correlations and discuss plausible physical mechanisms that may be driving them.