The mass-metallicity relation (MZR) describes how gas-phase metallicity is observed to primarily depend on stellar mass in galaxies. However, is this an intrinsic fundamental dependence, or is the stellar mass simply a proxy for other properties such as the dynamical mass or gravitational potential? 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. In this presentation I will present analysis of both spatially resolved and global data from the MaNGA survey and apply partial correlation coefficients and random forest regression to untangle the intrinsic dependencies of both the global and resolved metallicity. I will show that, based on these analyses, the global metallicity depends primarily on the stellar mass, not the dynamical mass or gravitational potential, thereby suggesting the MZR is likely a result of integrated metal production rather than a stronger gravitational well scenario. I will also show that 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 all these intrinsic correlations and discuss plausible physical mechanisms that may be driving them.
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