0 Assigned ID: 580 ----- Attempting Submission 1 (Fri Apr 11 16:42:42 GMT 2014) ----- HST Phase I Proposal 580 (LocalGroupSFH.apt) successfully submitted. ----- Attempting Submission 2 (Fri Apr 11 16:57:02 GMT 2014) ----- HST Phase I Proposal 580 (LocalGroupSFH.apt) successfully submitted. ----- Attempting Submission 3 (Fri Apr 11 17:06:17 GMT 2014) ----- HST observations of the Milky Way and M31's satellite galaxies show that those galaxies have an incredible diversity of star-formation histories, yet with the exception of the Magellanic Clouds, NGC205, and NGC185, none have active star formation or cold gas at the present. What accounts for the variation in star-formation histories, and what turns off star formation? We propose to use the publicly available Galacticus semi-analytic modeling code to explore the mechanisms for star formation and quenching of Local Group dwarf galaxies, comparing the satellite galaxies of the Milky Way and M31 with the star-forming "field" galaxies of the Local Group. We will create new modules for Galacticus to incorporate physical processes necessary to follow star formation and quenching (e.g., ram- pressure and tidal stripping and compression of gas), and perform a Markov Chain Monte Carlo analysis of the HST-derived star-formation histories to determine the best-fit physical model and degeneracies of parameters for star formation in the Local Group. These new modules and the Markov chains will be publicly released via the Galacticus web server. With this study, we can determine to what extent the star-formation histories and quenching of Local Group dwarfs are governed by physical processes that depend on properties of the Milky Way and M31's dark and gas halos versus other "external" (e.g., reionization-induced photoionization) or "internal" (e.g., supernova feedback) processes. This study will be a window into the broader question of star formation in dwarf galaxies. COSMOLOGY Default Medium false false false false true SUPPORTED