Untangling Galaxy Evolution in the New Spectroscopic Era
Prof. Allison Strom
Department of Physics and Astronomy
Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)
Northwestern University
A central goal of modern astrophysics is to understand how galaxies grow and change over the 14 Gyr of cosmic history. To achieve this goal, it is necessary to disentangle the competing effects of the many baryonic processes that govern galaxy evolution alongside the dark matter-dominated growth of large scale structure---including accretion of gas from the cosmic web, as well as outflows and feedback driven by massive stars and accreting supermassive black holes. These processes are difficult to observe directly, and an added complication is that much of what we know about the galaxy population is based on the present-day Universe (z~0), even though the vast majority of stars in galaxies were formed at much earlier times (z>1, more than ~7 Gyr ago). Fortunately, using new facilities like the James Webb Space Telescope (JWST) and premier ground-based observatories like the Keck Telescopes, we are now on the cusp of being able to study galaxies in detail at all cosmic times. I will share recent progress in characterizing the galaxy population during the peak of galaxy assembly 10-12 Gyr ago (z~2-3), including efforts by my group to use extremely deep Cycle 1 JWST/NIRSpec observations to accurately determine the chemical abundances in these distant galaxies. I will also preview science that will soon be possible with a large upcoming galaxy survey using the new Prime Focus Spectrograph (PFS) on the Subaru Telescope, which will target hundreds of thousands of galaxies during the period 5-10 Gyr ago when many were transitioning from highly star-forming to relatively quiescent, like the majority of galaxies today.
Hosted by Prof. Howk