Speaker
Description
The Circumgalactic Medium (CGM) is instrumental in the evolution of galaxies and a major player in their baryon cycles. The interface between the CGM and galactic disk is particularly important as it can show signatures of gas accretion and outflows driven by stellar winds, supernovae, and AGN. I will present our investigation into the metal absorption features associated with the CGM of 34 local (z ≲ 0.05) galaxies as part of the Deciphering the Interplay Between the Interstellar medium, Stars, & Circumgalactic medium (DIISC) survey. The DIISC survey has the advantage of characterizing the CGM in terms of a galaxy’s H I disk. Our data find it to be a better tracer of the cool metals content than the galaxy’s virial radius, which is typically used. More metal rich clouds (in both number and content) are seen closer to galaxies, indicative of precipitation occurring in their CGM. I will also highlight a sight line from an ongoing project which shows absorption features due to molecular hydrogen, along with metals tracing a range of gas – phases, at an impact parameter of 139 kpc (approximately 9 times the size of the galaxy’s stellar disk). This result will inform future theoretical models about how cold, dense gas is transported to these distances.