The neutral interstellar medium (ISM) is a vital player in the star formation process, based on its major contribution to the ISM’s mass, and bears the brunt of the stellar feedback. In particular, the cold neutral medium (CNM) regulates the transition from atomic to molecular gas and plays a central role in star formation and galaxy evolution. As numerical simulations of galaxy evolution continue to include more complex ISM physics, detailed understanding of how local conditions and stellar feedback affect the CNM formation and survival are essential.
In this talk, I will focus on what we know about the CNM properties in the Milky Way, specifically the CNM fraction, spatial extent, and physical properties that are most conducive for the formation of molecular hydrogen. I will also highlight what we know about the properties of the CNM in the nearby Magellanic Clouds based on observations with the Galactic ASKAP (GASKAP-HI). This survey offers a wealth of HI absorption detections, allowing complementary tests of neutral gas thermodynamics under low metallicity and intense radiation field, as well as local dynamical events provided by numerous expanding shells.
Contact local: Patrick HENNEBELLE
Organisation: Frédéric GALLIANO
DAp