Abstract:
Clouds more massive than about 105 M⊙ are potential sites of massive cluster formation. Studying the properties of such clouds in the early stages of their evolution offers an opportunity to test various cluster formation processes. We make use of CO, Herschel, and UKIDSS observations to study one such cloud, G148.24+00.41. Our results show the cloud to be of high mass (∼1.1×105 M⊙), low dust temperature (∼ 14.5 K), nearly circular (projected radius ∼ 26 pc), and gravitationally bound with a dense gas fraction of ∼18 per cent and a density profile with a power-law index of ∼−1.5. Comparing its properties with those of nearby molecular clouds, we find that G148.24+00.41 is comparable to the Orion-A molecular cloud in terms of mass, size, and dense gas fraction. From our analyses, we find that the central area of the cloud is actively forming protostars and is moderately fractal with a Q-value of ∼ 0.66. We also find evidence of global mass-segregation with a degree of mass-segregation (ΛMSR) ≈ 3.2. We discuss these results along with the structure and compactness of the cloud, the spatial and temporal distribution of embedded stellar population and their correlation with the cold dust distribution, in the context of high-mass cluster formation. We compare our results with models of star cluster formation, and conclude that the cloud has the potential to form a cluster in the mass range ∼ 2000-3000 M⊙ through dynamical hierarchical collapse and assembly of both gas and stars.