Physical parameters of 15 intermediate-age LMC clusters from modelling of HST colour-magnitude diagramsKerber, L.; Santiago, B.; Brocato, E.
We analyzed HST/WFPC2 colour-magnitude diagrams (CMDs) from 15 populous Large Magellanic Cloud (LMC) stellar clusters with ages between $\sim$ 0.3 Gyr and $\sim$ 3 Gyr. These (V, B-V) CMDs, provided by Brocato et al. (2001), are photometrically homogeneous and reach typically V$\sim$22. Accurate and self-consistent physical parameters (age, metallicity, distance modulus and reddening) were extracted for each cluster by comparing the observed CMDs with synthetic ones. These determinations were made by means of simultaneously statistical comparison of MS fiducial lines and red clump position, offering an objective and robust criteria to determine the best models. The models explored a regular grid in the parameter space consistent with previous results found in the literature. Control experiments were used to test our approach. In general, the best models shown a satisfactory fit to the data, constrainting well the physical parameters of each cluster. The derived distance modulli implied by the most reliable solutions, correlate with the reddening values, as expected from the non-negligible three-dimensional distribution of the clusters within the LMC. The inferred spatial distribution for the IACs is roughly aligned with the LMC disk, being also more scattered than recent numerical predictions (Bekki \& Chiba 2005), indicating that these clusters did not form in the LMC disk.