How it started . . . How it’s going: tracing the formation and evolution of massive galaxies through cosmic time

May 25, 2023 - 11:00 am to 12:00 pm

Campus, PAB 102/103

Rachel Bezanson (University of Pittsburgh) In Person and zoom

Zoom Recording

Galaxies are extraordinarily complex collections of stars, gas, and dark matter. The largest galaxies, though relatively rare in number, host most of the stars in the Universe and deep in their cores harbor the most extreme supermassive black holes. Today massive galaxies are red and dead ellipticals with little ongoing star formation or organized rotation; naturally they were expected to be relics of a much earlier formation epoch. In this talk I will briefly review the paradigm that has emerged over the last decade, discussing the structural and kinematic evolution of massive galaxies during and after they stopped forming stars (“quenched”) and eventually transformed from rotationally supported disks into kinematically hot ellipticals. I will describe my team’s observational efforts to characterize the histories of galaxies like our Milky Way and larger at several critical moments in the 14 billion year history of the Universe, each corresponding to a large spectroscopic program. Spectroscopic studies of distant galaxies reveal the chemical compositions, detailed star formation histories, and internal motions of stars and gas and are necessary to answer open questions about the details of that cosmic formation and shutdown. This work includes studying galaxy metamorphosis at ~half the age of the Universe, highlighting results from the ultra-deep LEGA-C spectroscopic survey of ~3500 massive galaxies and the focused multi-wavelength SQUIGGLE survey of post-starburst galaxies caught immediately following their cosmic shutdown. Finally, I will discuss our JWST UNCOVER treasury program that will extend deep spectroscopic studies of galaxies to the earliest moments in cosmic history.