0 Assigned ID: 1181 ----- Attempting Submission 1 (Thu Feb 28 00:41:22 GMT 2013) ----- HST Phase I Proposal 1181 (satellites_2013.apt) successfully submitted. ----- Attempting Submission 2 (Thu Feb 28 19:45:50 GMT 2013) ----- HST Phase I Proposal 1181 (satellites_2013.apt) successfully submitted. ----- Attempting Submission 3 (Fri Mar 01 17:33:26 GMT 2013) ----- We will measure the luminosity function and colors of ~10,000 satellites up to 10,000 times fainter than their hosts, and their evolution over cosmic time (0.1<z<1.4), by applying well-tested image processing and statistical tools to public datasets in the CANDELS fields. This unprecedented measurement will allow us to conduct a new test of galaxy formation models and the nature of dark matter, breaking degeneracies in the interpretation of local measurents of the satellite luminosity function. Semi-analytic models applied to cosmological simulations have been shown to reproduce the low redshift luminosity function of Milky Way satellites by combining differing strengths of supernovae and AGN feedback, stellar winds, UV heating during reionization, ram-pressure stripping and tidal torques exerted by the host halos. Alternatively, the local luminosity function of satellites can also be matched by warm dark matter models. However, different CDM and WDM models make clear and distinctly varying predictions for the dependency of the colors and luminosity function of satellite galaxies over varying redshift and host stellar mass intervals (Nierenberg et al. 2013), which we will conclusively test with our analysis. COSMOLOGY 12 Small false false 0.0 0.0 false false false SUPPORTED