Science with FEASTS
The interaction between IGM, CGM, ISM, and stars of galaxies
CGM cooling
CGM cooling and diffuse HI formation induced by tidal interaction
In Wang et al. (2023), making use of HI data from FEASTS, we discover a large-scale, low-density, and diffuse HI in the group NGC 4631 which was missed in previous deepest type of interferometric HI observation. This diffuse HI may represent a condensing phase of the hot and ionized IGM. Active tidal interactions on-going and in the past may have produced the wide-spreading HI distribution, and triggered the gas accretion to NGC 4631 through the phase of the diffuse HI.