Devontae Baxter: The Physics Driving Galaxy Evolution in Extreme Environments

WSU Physics Colloquium: 21 November 2024

Devontae Baxter: The Physics Driving Galaxy Evolution in Extreme Environments

The fate of a galaxy is intricately tied to its location within the cosmic web. Galaxies residing in underdense regions, such as voids and filaments, are much more likely to be gas-rich, star-forming spirals. In contrast, galaxies inhabiting overdense regions, such as galaxy groups and clusters, are more likely to be gas-poor ellipticals with little to no ongoing star formation. My research is fundamentally focused on understanding the physics that governs the interplay between environment and galaxy formation and evolution, motivated by several unresolved questions, such as: What physical mechanisms give rise to the overabundance of non-star-forming (or "quenched") galaxies in galaxy groups and clusters? As the densest regions in the distant universe, what role did protoclusters play in shaping present-day galaxy cluster populations? And how can we explain observations of dwarf galaxies that appear to have quenched their star formation in isolation? My primary tools for answering these questions involve a combination of multi-wavelength observations of galaxies across a range of environments and cosmic epochs, along with analytical models and state-of-the-art cosmological simulations. In this talk, I will share how these tools have yielded significant insights into the physical mechanisms responsible for halting star formation in galaxies within groups and clusters over the past 8 billion years. Moreover, I will discuss my ongoing research that seeks to solve the mystery of isolated quenched dwarf galaxies and quantify the role
that protocluster environments played in early massive galaxy evolution and quenching. By addressing these questions, my work aims to bring us closer to forming a comprehensive picture of the physics driving galaxy evolution, from low-density voids to densely packed galaxy clusters.