2025-05-27 –, Main Conference Room
Galaxies are in constant evolution, under the influence of the gas-star matter cycle within them. However, the exact physical mechanisms driving this multi-scale cycle remain elusive, due to a lack of observational constraints. By combining high-resolution, multi-wavelength observations from a broad range of galactic environments, I will present how we can characterise for the first time the successive steps of this cycle, from the assembly of dense gas clouds from the diffuse interstellar medium, to the successive collapse, star formation and dispersal by stellar feedback redistributing matter and energy back into the diffuse medium. I will show that molecular clouds are rapidly destroyed by pre-supernova stellar feedback (within 1-5 Myr), which drastically limit their star formation efficiency to 2 to 10%, depending on the galactic environment. The vast majority of momentum and energy emitted by the young stellar populations escapes the parent cloud, affecting galaxies on large scales. This comprehensive analysis sheds new light on the matter cycle within galaxies, revealing its underlying processes and quantitative characteristics. I will conclude by showing how these measurements provide critical constrains to improve the description of the unresolved processes of star formation and feedback in galaxy formation and evolution simulations.
