Constraints on the origin of Manganese from the composition of the Sagittarius Dwarf Spheroidal Galaxy and the Galactic Bulge
نویسنده
چکیده
The trend of [Mn/Fe] in the Galactic bulge follows the solar-neighborhood relation, but most stars in the Sagittarius dwarf spheroidal galaxy (Sgr dSph) show [Mn/Fe] deficient by ∼0.2 dex. This leads us to conclude that the Mn yields from both type Ia and type II SNe are metallicity-dependent. Our observations militate against the idea, suggested by Gratton, that Mn is over-produced 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 lowmass satellites into the Milky Way.
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