David DePalma

David probes the circumgalactic medium (CGM)—the gas immediately surrounding a galaxy in its halo of dark matter but beyond the galaxy’s disk or interstellar medium—to understand how the CGM records the galaxy’s history of formation and evolution through the baryon cycle. As a member of the Cosmic Ultraviolet Baryon Survey (CUBS; https://cubs.uchicago.edu), David matches absorbers from a galaxy survey with absorptions in quasar spectra.

For CUBS, David observes, reduces observations, measures redshifts, analyzes spectral energy distributions on cluster computers, develops stacking algorithms, and compares his findings to those of theorists’ simulations. Beyond CUBS, he contributes to programs about the epoch of reionization through quasar lifetimes, gravitational lensing, and enrichment of the intergalactic medium through the CGM. David also participates in public engagement. He observes at optical and infrared wavelengths with the Magellan Telescopes plus optical and ultraviolet wavelengths with the Hubble Space Telescope.