In hydrodynamic simulations, prevailing subgrid chemical-evolution models
often use a single, "IMF-averaged" supernova yield, ignoring variations in
elemental abundance ratios (particularly [α/Fe]) in the ejecta of
higher- and lower-mass supernova progenitors within a stellar population. To
understand the impact of this simplification and understand the impact of more
explicit models, we run FIRE simulations of a dwarf galaxy (M⋆​(z = 0)∼106M⊙​) using nucleosynthetic yields from the NuGrid database that
depend on the stellar progenitor mass and metallicity. While NuGrid exhibits
lower aggregate α-element production than default-FIRE yields, we find
that its explicit mass dependence substantially widens the intrinsic scatter in
the simulated [Fe/H]-[α/Fe] -- a phenomenon potentially visible in
recent observations of dwarf galaxies.Comment: MNRAS submitted. 7 pages; 6 figures. Comments and questions welcom