Collaborative Research: A Matter of Timing: Star Formation Suppression Over the Last Half of Cosmic History

This research team will study galaxies that just recently shut down their last burst of star formation, transforming from youthful active galaxies like our own Milky Way into sedate galaxies that age in place. While this process normally takes billions of years, the team has developed methods to find galaxies that experienced a rapid cutoff in star formation. The project will further develop these methods and use a wide set of data from telescopes around the world to understand why galaxies do (or don't) rapidly quench star formation. The program will support research experiences for undergraduate students at both Texas A&M University and the University of Colorado Boulder. Using novel modeling methods, the team has developed for large ground-based spectroscopic surveys, hundreds of massive galaxies that quenched their star formation within the last billion years have been discovered. The team will use an extensive multi-wavelength dataset for about 50 of these post-starburst galaxies to measure dust and cold gas masses, assess the incidence of active galactic nuclei, and measure obscured star formation. The team will also extend the selection methods to identify galaxies that quenched on slower timescales, which become increasingly prevalent at low redshifts. In addition, the team will expand existing research support programs for undergraduate students to include community building and skill-sharing exercises. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.