Newly Identified Star Clusters in M33. II. Radial HST/ACS Fields
  We present integrated photometry and color-magnitude diagrams for 161 star
clusters in M33, of which 115 were previously uncataloged, using the Advanced
Camera For Surveys Wide Field Channel onboard the Hubble Space Telescope. The
integrated V-band magnitudes of these clusters range from Mv~-9 to as faint as
Mv~-4, extending the depth of the existing M33 cluster catalogs by ~1 mag.
Comparisons of theoretical isochrones to the color-magnitude diagrams using the
Padova models yield ages for 148 of these star clusters. The ages range from
Log (t)~7.0 to Log (t)~9.0. Our color-magnitude diagrams are not sensitive to
clusters older than ~1 Gyr. We find that the variation of the clusters'
integrated colors and absolute magnitudes with age is consistent with the
predictions of simple stellar population models. These same models suggest that
the masses of the clusters in our sample range from 5x10^3 to 5x10^4 *Msun.
