Physics Colloquium with Yuanyuan Zhang on Optical Cosmic Surveys
With the largest telescopes and a systematic approach to photograph the sky, optical cosmic survey programs are on a mission to decipher the makeup of the universe, from the nature of the mystical dark energy to the astrophysical processes that shape the formation of galaxies. Ongoing and upcoming cosmic survey programs, like the Dark Energy Survey and the Legacy Survey of Space and Time at the Vera Rubin Observatory, take images of a large swath of the Sky, wide and deep enough to map out the cosmic structure growth history in the past one billion years. A main goal of these survey programs is to constrain dark energy through observations of large scale structures. These studies include galaxy clusters, the most massive cosmic structures in the universe. During this talk, I will start by introducing the Dark Energy Survey as well as the upcoming Legacy Survey of Space and Time, then describe their cosmological ambitions with large scale structures, and finally dig into how these surveys also bring changes to astrophysical studies with an example of measuring the low surface brightness features of galaxy clusters.