October 28
The structure of the molecular ISM in nearby starbursts : a cloud-scale view with ALMA, JWST, and MUSE
Speaker: Elias Oakes, U Conn
Abstract: The structure and dynamical state of molecular gas set where, when, and how efficiently stars form, yet our observational picture is historically divided between extragalactic surveys mapping whole galaxies at ~100 pc resolution and Milky Way studies that resolve sub-parsec structure in a handful of regions. I will present work beginning to bridge that gap with high-resolution surveys of NGC 253 and NGC 4945, two of the nearest massive, molecule-rich starburst galaxies. By decomposing the molecular gas into thousands of hierarchically nested structures from 3 to 300 pc, I show that there is no characteristic scale at which gravitationally bound structures emerge. Looking in towards individual gas peaks, I find that their inner density profiles match those of Milky Way cores at orders of magnitude smaller scales. Near exposed star-forming regions, feedback visibly disrupts the clouds' shapes but leaves their underlying density structure unchanged. Finally, I will introduce a new, 12 pc survey of the full disk of NGC 4945 and discuss how the coming generation of cloud-scale, galaxy-wide surveys with ALMA, JWST, and MUSE will benchmark our models of star formation across diverse environments.
Host: Prof. Alberto Bolatto