Resolving the Baryon Cycle within Nearby Galaxies

The buildup of stellar mass through star formation is driven on small (<100pc) scales by physical processes and local conditions, but regulated across larger (kpc) scales through the baryon cycle. This entails the transformation of gas into stars, and eventual ejection and recycling of material to form the next generation of stars. The interstellar medium (ISM) provides crucial insights into these processes, particularly our understanding of radiative and mechanical feedback from young massive stars. The PHANGS (Physics at High Angular resolution in Nearby GalaxieS) collaboration is building a library of uniform, high-quality, high-resolution observations of nearby galaxies at the critical “cloud scale” across star-forming galaxy disks by using observations from Hubble, MUSE/VLT, JWST, and ALMA. This provides a characterization of the young star clusters, the ionized HII regions, the supernova remnants and the giant molecular clouds, with which we can explore a comprehensive view of the star-formation process.
I will present new results from my group, which has focused on quantifying the impact of these stellar feedback processes on the ISM. I will show how we are leveraging our large statistical samples to establish an evolutionary sequence for HII regions, linking ionized nebulae with their powering stellar sources. In charting the late-time and large-scale feedback, I will show how morphological identification of bubbles in molecular and ionized gas, and now with JWST in the dust, provides quantitative constraints on different feedback mechanisms. Finally, I will show how the Local Volume Mapper (LVM) project within SDSS-V will push us towards a 1-10pc view of these physical processes within our own Milky Way and Local Group (LMC/SMC) galaxies.