The youngest stellar clusters
Clusters associated with massive protostellar candidates
Centro de Astrofísica da Universidade do Porto, Rua das Estrelas, 7150-462 Porto, Portugal e-mail: firstname.lastname@example.org
2 Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts, USA
Accepted: 19 December 2005
We report on the identification of 54 embedded clusters around 217 massive protostellar candidates of which 34 clusters are new detections. The embedded clusters are identified as stellar surface density enhancements in the 2 μm All Sky Survey (2MASS) data. Because the clusters are all associated with massive stars in their earliest evolutionary stage, the clusters should also be in an early stage of evolution. Thus the properties of these clusters should reflect properties associated with their formation rather than their evolution. For each cluster, we estimate the mass, the morphological type, the photometry and extinction. The clusters in our study, by their association with massive protostars and massive outflows, reinstate the notion that massive stars begin to form after the first generation of low mass stars have completed their accretion phase. Further, the observed high gas densities and accretion rates at the centers of these clusters is consistent with the hypothesis that high mass stars form by continuing accretion onto low mass stars.
Key words: stars: formation / HII regions / open clusters and associations: general
© ESO, 2006