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

Andrew McWilliam·R. Michael Rich·Tammy A. Smecker-Hane
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Abstract

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 approximately 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 low-mass satellites into the Milky Way.

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Andrew McWilliam, R. Michael Rich, Tammy A. Smecker-Hane. 2003-06-27. Constraints on the Origin of Manganese from the Composition of the Sagittarius Dwarf Spheroidal Galaxy and the Galactic Bulge. https://doi.org/10.1086/378263

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