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arXiv · 1704.02067

Mass-size scaling M~ r^1.67 of massive star-forming clumps -- evidences of turbulence-regulated gravitational collapse

Chuan-Peng Zhang·Guang-Xing Li
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Abstract

We study the fragmentation of eight massive clumps using data from ATLASGAL 870 $\mu$m, SCUBA 850 and 450 $\mu$m, PdBI 1.3 and 3.5 mm, and probe the fragmentation from 1 pc to 0.01 pc scale. We find that the masses and the sizes of our objects follow $M \sim r^{1.68\pm0.05}$. The results are in agreements with the predictions of Li (2017) where $M \sim r^{5/3}$. Inside each object, the densest structures seem to be centrally condensed, with $\rho(r)\sim r^{-2}$. Our observational results support a scenario where molecular gas in the Milky Way is supported by a turbulence characterized by a constant energy dissipation rate, and gas fragments like clumps and cores are structures which are massive enough to be dynamically detached from the ambient medium.

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Chuan-Peng Zhang, Guang-Xing Li. 2017-04-07. Mass-size scaling M~ r^1.67 of massive star-forming clumps -- evidences of turbulence-regulated gravitational collapse. https://doi.org/10.1093/mnras%2Fstx954

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