Stellar Population Analysis in the Milky Way and Beyond

There is a diversity in the types of galaxies that exist - in their mass, morphology, environment, and activity - that point to a diversity in formation pathways, and the Milky Way is but one of them. Yet, studying the Milky Way’s stellar populations, their detailed chemical abundances, kinematics, and other properties, provides us with an unparalleled view of galaxy formation. The forefront of astrophysical research lies in the intersection of the two: where we can use our knowledge of the Milky Way’s resolved stellar populations and other nearby galaxies’ unresolved stellar populations to understand galaxy formation holistically. This is the topic of my dissertation: analyzing stellar populations - both resolved in the Milky Way and unresolved in nearby galaxies - to bridge the gap between the two fields that actually use and inform one another. For the resolved stellar populations part, I will present my results on the detailed chemical abundances, especially in the neutron-capture elements, for stars from the accreted satellite system dubbed Gaia-Enceladus. Specifically, I will discuss the chemical evolution implications of the abundance trends that we measure, in the context of other Milky Way satellites. For the unresolved stellar populations part, I will present my work on the growth and assembly of the different components — the bulge, bar, and disk— of the nearby galaxy NGC 2903, using the VIRUS-P Exploration of Nearby Galaxies (VENGA) Integral Field Spectroscopy (IFS) survey. Lastly, I will discuss how we can further bridge the gap, as the unresolved stars become resolved, using next generation spectroscopic surveys and the unique perspective provided by simulations.