Jiayi Sun

Team Member Profile: Jiayi Sun

Position: PhD candidate (Presidential Fellow) at Ohio State University

Professional webpage: https://astrojysun.github.io

General science interest: I would like to understand the physical processes shaping the cold interstellar medium in galaxies. I specialize in the study of molecular clouds through millimeter-wave observations. My current main focus is on characterizing the demographics of molecular clouds and their links to star formation, stellar feedback, and galaxy dynamics.

My role in PHANGS: Using the PHANGS-ALMA CO data, I construct the largest ever measurement set capturing molecular gas properties on 50-150 parsec scales across the local star-forming galaxy population (Sun et PHANGS (2018); Sun et PHANGS 2020b, in prep.). I use this measurement set to demonstrate how molecular clouds "acclimatize" themselves to their ambient environment. I further conduct a joint analysis of the PHANGS-ALMA CO data and multiwavelength supporting data, and reveal key mechanisms regulating molecular cloud properties and star formation processes across a wide range of star-forming environments (Sun et PHANGS 2020a).


This figure demonstrates how molecular gas properties on 120 parsec scales vary within and across galaxies (see Sun, J. and the PHANGS Collaboration, 2018). The spread in molecular gas surface density and velocity dispersion (top), dynamical state (bottom left), and turbulent pressure (bottom right) is evident across the 15 nearby galaxies examined. There is also a clear contrast between normal star-forming galaxies (blue, including 11 PHANGS-ALMA targets), a merger system (orange), and two more quiescent galaxies (green).