Tracking the simulated Local Group CGM and modeling Milky Way contamination in mock observations of M31
This video presents a study by Damle et al. (2022) , that analyzes the Local Group’s circumgalactic medium (CGM) in the Hestia constrained simulations . We generate skymaps as well as column density maps for a bunch of tracer ions, employed in order to probe the multi-phase nature of the CGM.
Our neutral Hydrogen and Si III skymaps show many satellite galaxies lying at virial radii distances from the Milky Way and M31. These could potentially contribute significantly to the cool gas budget in the Local Group. Our results show that while the M31 galaxies in Hestia under-produce cool gas as compared to the spectroscopic M31 observations, our galaxies are consistent with the observations from the low-redshift regime. We infer that contamination from Milky Way and its CGM (which also includes some satellite galaxies) could be one of the reasons potentially boosting cool gas column densities in spectroscopic M31 observations.