Oct 25, 2018 4:00 pm - Nielsen Hall 170 - Colloquium
Duane Lee - MIT
Playing Your CARDs Right: Leveraging (One-Shot) Galactic Chemical Evolution Models to Understand and Predict Chemical Abundance

The inherent rates and elemental yields for neutron star mergers and supernova should be reflected in the chemical abundance ratio distributions (CARDs) we see in various galactic systems (e.g., ultra-faint dwarfs, classical dwarfs, Milky Way Halo) today. In this talk, I will briefly present a semi-analytic framework from which parameters and values can be calculated using observed data, generic semi-analytic models (Bullock & Johnston 2005, Roberston et al. 2005, Font et al. 2006) to recover Galactic accretion histories (Lee et al. 2015) and the ` one-shot' dwarf galaxy models from Lee et al. (2013) to calculate, e.g., star formation efficiencies and Hydrogen dilution masses (Lee & Frebel [in prep]). In our new preliminary work, we find that trends found [Sr/Eu]-[Eu/H] chemical abundance plane and those found in other abundance ratio observations can be explained by a consistent neutron star merger Eu yield and mean Sr yield from supernova coupled with various Hydrogen dilution masses. These dilution masses correspond with various star formation efficiencies consistent with the observations, the models used, and galactic chemical evolution theory.