The ratio of [Eu/$\alpha$] differentiates accreted/in-situ Milky Way stars across metallicities, as indicated by both field stars and globular clusters

Stephanie Monty, Vasily Belokurov, Jason L. Sanders +7

We combine stellar orbits with the abundances of the heavy, $r$-process element europium and the light, $\alpha$-element, silicon to separate in-situ and accreted populations in the Mil…