A Photometric Catalog of 77 Newly-recognized Star Clusters in M31
  This paper describes the results of an HST WFPC2 search for star clusters in
active star-formation regions of M31. Nine of the clusters were previously
cataloged and 77 are new. Our 23 fields cover key areas of the galaxy's recent
star formation activity. We provide a catalog of positions and integrated
magnitudes in four colors, taken with the 336W, 439W, 555W and 814W filters
with the Hubble Space Telescope. A future paper will discuss the results of
stellar photometry in some of the clusters in six colors, including two
additional uv colors (Bianchi et al. 2010). The integrated magnitudes and
colors of the clusters show a range of characteristics, but the mean color is
bluer than for previous surveys, reflecting the concentration of our sample on
active star forming regions. Absolute magnitudes range from M555 = -10.3 to -
3.5. The observed luminosity function shows a nearly Gaussian distribution with
a peak value at M555 = -5.4 and a shoulder of unusually-bright clusters. We
look in detail at two of these unusually bright examples, cluster 45 (C410) and
cluster 10 (BH05). C410 lies at the core of a bright HII region. Its absolute
magnitude is M555 = -10.3. BH05 is a similar object, with an absolute magnitude
of M555 = -8.9. These two clusters are among the most luminous young clusters
in M31.
