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arXiv · 1609.06366

The JCMT Gould Belt Survey: Dense Core Clusters in Orion A

Abstract

The Orion A molecular cloud is one of the most well-studied nearby star-forming regions, and includes regions of both highly clustered and more dispersed star formation across its full extent. Here, we analyze dense, star-forming cores identified in the 850 {\mu}m and 450 {\mu}m SCUBA-2 maps from the JCMT Gould Belt Legacy Survey. We identify dense cores in a uniform manner across the Orion A cloud and analyze their clustering properties. Using two independent lines of analysis, we find evidence that clusters of dense cores tend to be mass segregated, suggesting that stellar clusters may have some amount of primordial mass segregation already imprinted in them at an early stage. We also demonstrate that the dense core clusters have a tendency to be elongated, perhaps indicating a formation mechanism linked to the filamentary structure within molecular clouds.

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J. Lane, H. Kirk, D. Johnstone, S. Mairs, J. Di Francesco, S. Sadavoy, J. Hatchell, D. S. Berry, T. Jenness, M. R. Hogerheijde, D. Ward-Thompson. 2016-09-20. The JCMT Gould Belt Survey: Dense Core Clusters in Orion A. https://doi.org/10.3847/1538-4357/833/1/44

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