| Abstract |
Feedback from active galactic nuclei (AGN) is thought to aid in quenching star formation in massive galaxies. However, studies of galaxies undergoing quenching (“post-starburst” galaxies) use selection methods that exclude AGN signatures, especially the blue continuum from luminous quasars. This means we cannot answer the most fundamental question about AGN feedback: Do AGN occur at a high enough rate and luminosity during the post-starburst phase to quench star formation? The Deep Tier of Roman’s High-Latitude Wide-Area Survey will observe both photometry and sensitive enough spectra to obtain line fluxes for ~10,000 post-starburst galaxies at 1 < z < 2, the epoch during which most local massive quiescent galaxies ceased forming stars. We will use this data to perform the first ever census of AGN activity in post-starburst galaxies that blindly surveys galaxies undergoing quenching without first selecting for or against luminous quasars. The rest-frame UBV colors and broad Balmer luminosities available with Roman will allow us to clearly separate populations of post-starburst galaxies with quasar emission, including them for the first time in a post-starburst survey at this crucial redshift range. By computing the fraction and luminosities of AGN in the post-starburst phase, we will determine whether AGN feedback can account for and/or is necessary to form the massive quiescent galaxy population we see today. |