We present the recently updated and expanded MASSCLEANcolors, a database of
70 million Monte Carlo models selected to match the properties (metallicity,
ages and masses) of stellar clusters found in the Large Magellanic Cloud (LMC).
This database shows the rather extreme and non-Guassian distribution of
integrated colors and magnitudes expected with different cluster age and mass
and the enormous age degeneracy of integrated colors when mass is unknown. This
degeneracy could lead to catastrophic failures in estimating age with standard
SSP models, particularly if most of the clusters are of intermediate or low
mass, like in the LMC. Utilizing the MASSCLEANcolors database, we have
developed MASSCLEANage, a statistical inference package which assigns the most
likely age and mass (solved simultaneously) to a cluster based only on its
integrated broad-band photometric properties. Finally, we use MASSCLEANage to
derive the age and mass of LMC clusters based on integrated photometry alone.
First we compare our cluster ages against those obtained for the same seven
clusters using more accurate integrated spectroscopy. We find improved
agreement with the integrated spectroscopy ages over the original photometric
ages. A close examination of our results demonstrate the necessity of solving
simultaneously for mass and age to reduce degeneracies in the cluster ages
derived via integrated colors. We then selected an additional subset of 30
photometric clusters with previously well constrained ages and independently
derive their age using the MASSCLEANage with the same photometry with very good
agreement. The MASSCLEANage program is freely available under GNU General
Public License.Comment: 17 pages, 11 figures. Accepted for publication in The Astrophysical
Journal. Full resolution figures available in journal versio