IFF-CSIC, Madrid, Spain
Stellar feedback in the ISM revealed by wide-field velocity-resolved imaging
The radiative and mechanical interaction of stars with their environment drives the evolution of the ISM and of galaxies as a whole. The far-IR [CII]158um, [OI]63,145um, and high-J CO emission lines dominate the cooling of the warm neutral gas in massive star-forming cores and in their very extended cloud environment. Understanding the properties of the cloud environment is of prime importance.
The extended far-IR line emission is the most sensitive probe of stellar feedback processes and of the gas heating mechanisms. These lines allow us to quantify the deposition and cycling of energy in the ISM, giving insight into the regulation process of star formation by different feedback processes. Their emission is widespread and typically bright ("easy" to map), and their velocity-resolved line profiles hide the critical information needed to understand the dynamics of these regions. They also allow us to unveil cloud components that cannot be seen in other tracers (e.g., because they are CO-dark or because they emit at slightly different systemic velocities).
In this talk I will emphasize the need of wide-field, high-spectral resolution (velocity resolved) line mapping of square degree areas of the ISM of our Galaxy and nearby galaxies: i.e., able to map entire star-forming complexes. Due to the lack of appropriate technology, both requirements: i) sub-km/s resolution in the far-IR and ii) access to very large spatial scales in reasonable observing times, have not really been exploited by previous space and airborne telescopes.
Moreover, since it is the large scale cloud emission that likely dominates the far-IR line emission from high-redshift star-forming galaxies (e.g., detected by ALMA), an observing program like this one will provide a unique laboratory and many useful templates to better understand the spatially unresolved far-IR line emission from the distant Universe.