2013MNRAS.433.1276S

We present the results of an infrared photometric survey performed with Near-Infrared Camera Spectrometer-Telescopio Nazionale Galileo 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 colours. These clusters are located in the combined ultraviolet-infrared colours 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 analysed clusters appear to be younger than logt/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 colour-colour diagram to select candidate young massive clusters hosting multiple stellar populations.