Studying the YMC population of M83: how long clusters remain embedded, their interaction with the ISM and implications for GC formation theories

• Published in: Monthly notices of the Royal Astronomical Society Vol. 449; no. 1; pp. 1106 - 1117
• Main Authors: Hollyhead, K., Bastian, N., Adamo, A., Silva-Villa, E., Dale, J., Ryon, J. E., Gazak, Z.
• Format: Journal Article
• Language: English
• Published: London Oxford University Press 01.05.2015
• Subjects: Age; Astronomy; Clusters; Constraining; Fittings; Formations; galaxies: star clusters: general; Globular clusters; Morphology; Spectra; Spectral energy distribution; Star & galaxy formation; galaxies: star clusters: general
• ISSN: 0035-8711; 1365-2966; 1365-2966
• DOI: 10.1093/mnras/stv331

The study of young massive clusters can provide key information for the formation of globular clusters, as they are often considered analogues. A currently unanswered question in this field is how long these massive clusters remain embedded in their natal gas, with important implications for the formation of multiple populations that have been used to explain phenomena observed in globular clusters. We present an analysis of ages and masses of the young massive cluster population of M83. Through visual inspection of the clusters, and comparison of their spectral energy distributions (SEDs) and position in colour–colour space, the clusters are all exposed (no longer embedded) by <4 Myr, most likely less, indicating that current proposed age spreads within older clusters are unlikely. We also present several methods of constraining the ages of very young massive clusters. This can often be difficult using SED fitting due to a lack of information to disentangle age–extinction degeneracies and possible inaccurate assumptions in the models used for the fitting. The individual morphology of the Hα around each cluster has a significant effect on the measured fluxes, which contributes to inaccuracies in the age estimates for clusters younger than 10 Myr using SED fitting. This is due to model uncertainties and aperture effects. Our methods to help constrain ages of young clusters include using the near-infrared and spectral features, such as Wolf–Rayet stars.