Paper detail

Infrared photometry of Young Massive Clusters in the starburst galaxy NGC 4214

We present the results of an infrared photometric survey performed with NICS@TNG in the nearby starburst galaxy NGC 4214. We derived accurate integrated JK magnitudes of 10 young massive clusters and compared them with the already available Hubble Space Telescope ultraviolet colors. These clusters are located in the combined ultraviolet-infrared colors planes on well defined sequences, whose shapes allow a precise determination of their age. By means of the comparison with suitable stellar evolution models we estimated ages, metallicities, reddening and masses of these clusters. All the analyzed clusters appear to be younger than log(t/yr)<8.4, moderately metal-rich and slightly less massive than present-day Galactic globular clusters. The derived ages for clusters belonging to the secondary HII star forming complex are significantly larger than those previously estimated in the literature. We also discuss the possibility of using the ultraviolet-infrared color-color diagram to select candidate young massive clusters hosting multiple stellar populations.