The Elemental Abundance Distributions of Milky Way Satellite Galaxies
  The chemical compositions of the stars in Milky Way (MW) satellite galaxies
reveals the history of gas flows and star formation (SF) intensity. This talk
presented a Keck/DEIMOS spectroscopic survey of the Fe, Mg, Si, Ca, and Ti
abundances of nearly 3000 red giants in eight MW dwarf satellites. The
metallicity and alpha-to-iron ratio distributions obey the following trends:
(1) The more luminous galaxies are more metal-rich, indicating that they
retained gas more efficiently than the less luminous galaxies. (2) The shapes
of the metallicity distributions of the more luminous galaxies require gas
infall during their SF lifetimes. (3) At [Fe/H] < -1.5, [alpha/Fe] falls
monotonically with increasing [Fe/H] in all MW satellites. One interpretation
of these trends is that the SF timescale in any MW satellite is long enough
that Type Ia supernovae exploded for nearly the entire SF lifetime.
