Constraints on the Origin of Manganese from the Composition of the Sagittarius Dwarf Spheroidal Galaxy and the Galactic Bulge

The trend of [Mn/Fe] in the Galactic bulge follows the solar neighborhood relation, but most stars in the Sagittarius dwarf spheroidal galaxy show [Mn/Fe] deficient by ~0.2 dex. This leads us to conclude that the Mn yields from both Type Ia and Type II supernovae (SNe) are metallicity dependent. Our observations militate against the idea, suggested by Gratton, that Mn is overproduced by Type Ia SNe, relative to Type II SNe. We predict Mn/Fe ratios, lower than the solar neighborhood relation, for the younger populations of nearly all dwarf galaxies, and that Mn/Fe ratios may be useful for tracing the accretion of low-mass satellites into the Milky Way.