Abstract details

We present results from our ongoing HST/ACS survey of the outer disks and halos of 14 nearby galaxies. The stellar halos of galaxies are commonly thought to be created by interaction, however there is little agreement how these structures scale with mass. Observationally, only the galaxies in the local group have been well characterized. We analyze the surface brightness profiles and metallicity distributions of resolved RGB stars in the outer regions of numerous nearby galaxies. In NGC 4244, a low-mass (V_c=93 km/sec), edge-on galaxy, we place strong upper limits on the existence of a stellar halo. We also present initial results showing that the surface brightness in the inner halo of M81 drops off much more quickly than in the Milky Way.