The stellar content of the infalling molecular clump G286.21+0.17

Abstract

The early evolution during massive star cluster formation is still uncertain. Observing embedded clusters at their earliest stages of formation can provide insight into the spatial and temporal distribution of the stars and thus probe different star cluster formation models. We present near-infrared imaging of an 8'*13'(5.4pc*8.7pc) region around the massive infalling clump G286.21+0.17(also known as BYF73). The stellar content across the field is determined and photometry is derived in order to { obtain} stellar parameters for the cluster members. We find evidence for some sub-structure (on scales less than a pc diameter) within the region with apparently at least three different sub-clusters associated with the molecular clump based on differences in extinction and disk fractions. At the center of the clump we identify a deeply embedded sub-cluster. Near-infrared excess is detected for 39-44% in the two sub-clusters associated with molecular material and 27% for the exposed cluster. Using the disk excess as a proxy for age this suggests the clusters are very young. The current total stellar mass is estimated to be at least 200 Msun. The molecular core hosts a rich population of pre-main sequence stars. There is evidence for multiple events of star formation both in terms of the spatial distribution within the star forming region and possibly from the disk frequency.

Submitted to AJ

References in corpus (7)

• Complex Chemistry in Star-Forming Regions: An Expanded Gas-Grain Warm-up Chemical Model
• Equilibrium Star Cluster Formation
• On the Rapid Collapse and Evolution of Molecular Clouds
• On the Structure of the Orion A Cloud and the Formation of the Orion Nebula Cluster
• The Structural Evolution of Forming and Early Stage Star Clusters
• The Galactic Census of High- and Medium-mass Protostars. III ${}^{12}$CO Maps and Physical Properties of Dense Clump Envelopes and their Embedding GMCs
• Empirical Near Infrared colors for low-mass stars and brown dwarfs in the Orion Nebula Cluster

Cited by in corpus (5)

• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- VI. On the formation of the "L" type filament in G286.21+0.17
• Gas Kinematics of the Massive Protocluster G286.21+0.17 Revealed by ALMA
• SOFIA and ALMA Investigate Magnetic Fields and Gas Structures in Massive Star Formation: The Case of the Masquerading Monster in BYF 73
• Stellar Variability in a Forming Massive Star Cluster
• The Disk Population in a Distant Massive Protocluster