A MegaCam Survey of Outer Halo Satellites. III. Photometric and
  Structural Parameters
  We present structural parameters from a wide-field homogeneous imaging survey
of Milky Way satellites carried out with the MegaCam imagers on the 3.6m
Canada-France-Hawaii Telescope (CFHT) and 6.5m Magellan-Clay telescope. Our
survey targets an unbiased sample of "outer halo" satellites (i.e.,
substructures having Galactocentric distances greater than 25 kpc) and includes
classical dSph galaxies, ultra-faint dwarfs, and remote globular clusters. We
combine deep, panoramic $gr$ imaging for 44 satellites and archival $gr$
imaging for 14 additional objects (primarily obtained with the DECam instrument
as part of the Dark Energy Survey), to measure photometric and structural
parameters for 58 outer halo satellites. This is the largest and most uniform
analysis of Milky Way satellites undertaken to date and represents roughly
three quarters ($58/81 \simeq$72\%) of all known outer halo satellites. We use
a maximum-likelihood method to fit four density laws to each object in our
survey: exponential, Plummer, King and Sersic models. We examine systematically
the isodensity contour maps and color magnitude diagrams for each of our
program objects, present a comparison with previous results, and tabulate our
best-fit photometric and structural parameters, including ellipticities,
position angles, effective radii, Sersic indices, absolute magnitudes, and
surface brightness measurements. We investigate the distribution of outer halo
satellites in the size-magnitude diagram, and show that the current sample of
outer halo substructures spans a wide range in effective radius, luminosity and
surface brightness, with little evidence for a clean separation into star
cluster and galaxy populations at the faintest luminosities and surface
brightnesses.
