The HST Survey of M31 Satellites ("M31-SATELLITES")

The HST Survey of M31 Satellite Galaxies used HST to obtain deep ACS/WFC3 imaging of 23 low-mass galaxies associated with M31. These data consist of primary ACS/WFC and parallel WFC3/UVIS fields observed with deep F606W and F814W exposures. In addition, the program homogeneously reprocessed archival data (consisting of ACS/WFC and WFC3/UVIS exposures in F475W, F606W, and F814W) for: 13 additional low-mass galaxies within 500 kpc from M31, 2 fields in the halo of M31, 8 fields in M33. The full survey is described in Savino et al. (2024). These observations were used to produce: i) deep photometric source catalogs (obtained with DOLPHOT, Dolphin 2000, 2016), ii) a census of the RR Lyrae population in the ACS fields, and iii) lifetime star formation histories from the ACS fields. New imaging for this program was taken to satisfy common first epoch proper motion requirements.