10) the relationship of age, Z and abundance of disk stars in a simulated Milky Way

Abstract: The age, metallicity, and chemical abundances of stars are the primary tools that we use in Galactic archaeology in order to understand how the Milky Way has formed. Observational studies have shown that stars at a given metallicity and age show very little dispersion in the abundance versus age plane, meaning that we only need the metallicity and age of a star to predict its chemical abundance. This has been posited to be due to similar birth location at a given age, in line with an inside-out scenario where star formation proceeds from the central parts to the outskirts of a galaxy with time. In this talk, we showcase our exploration of where this small age-abundance intrinsic dispersion comes from by taking advantage of the Ananke generative framework -- a Gaia mock catalog based on the Latte set of hydrodynamic zoom-in simulations of Milky-Way mass galaxies. Specifically, we compare where these simulations reproduce observational trends, and where this breaks down. We similarly find small dispersions (<0.02 dex) in the [X/Fe] vs age plane for the seven individual elements (C,N,O,Mg,Si,S,Ca) that we investigated. In addition, most of the [X/Fe]-age trends in the sims follow what we find in observations, except for C and Ca. This work has shown that the small intrinsic dispersion in the age-abundance relation is intimately linked to a star's birth location and has identified tensions between the observed and predicted trends in [X/Fe] as a function of age.

Bio: Andreia "Dreia" Carrillo is a 5th year grad student studying the detailed chemistry of Milky Way stars, using large surveys, spectroscopy, and zoom-in simulations. She also studies unresolved stellar populations in nearby galaxies using integral field unit data. She's a LSSTC Data Science Fellow and was a Simons Foundation CCA Predoc Fellow.