Project AMIGA: Mapping the Circumgalactic Medium of Andromeda

Our program will provide theoretical support for the interpretation of the Project AMIGA observations of the circum-galactic medium of Andromeda using a suite of high-resolution cosmological (zoom-in) hydrodynamical simulations. In turn, the AMIGA CGM measurements will provide new constraints on the physical processes implemented in our simulations, in particular stellar feedback from photoionization, radiation pressure, supernovae, and stellar winds. The specific AMIGA observational statistics that we will predict and test our simulations with are: the metallicity distribution of cool and warm phases, the total baryonic and metal masses of the CGM, and the kinematics of absorbers. Our cosmological simulations will use the FIRE (Feedback In Realistic Environments; http://fire.northwestern.edu) stellar feedback model, shown to successfully reproduce several key observational statistics of galaxies of masses of up to the mass of Andromeda, including the relationship between stellar mass and dark matter halo mass, the stellar and gas phase mass-metallicity relations, and the HI content of high-redshift galaxy halos without any parameter tuning. We will use these new constraints to inform the feedback models implemented in our next-generation simulations.