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arXiv · 1707.00234

Star formation conditions in a Planck Galactic Cold Clump, G108.84-00.81

Jungha Kim·Jeong-Eun Lee·Tie Liu·Kee-Tae Kim·Yuefang Wu·Ken'ichi Tatematsu·Sheng-Yuan Liu·JCMT Large Program "SCOPE" collaboration·TRAO Key Science Program "TOP" collaboration
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Abstract

We present the results from a series of ground-based radio observations toward a Planck Galactic Cold Clump (PGCC), PGCC G108.84-00.81, which is located in one curved filamentary cloud in the vicinity of an extended HII region Sh2-152 and SNR G109.1-1.0. PGCC G108.84-00.81 is mainly composed of two clumps, "G108-N" and "G108-S". In the 850 micron dust continuum emission map, G108-N is shown as one component while G108-S is fragmented into four components. There is no infrared source associated with G108-N while there are two infrared sources (IRS 1 and IRS 2) associated with G108-S. The total mass of G108-N is larger than the jeans mass, suggesting that G108-N is gravitationally unstable and a potential place for a future star formation. The clump properties of G108-N and G108-S such as the gas temperature and the column density, are not distinctly different. However, G108-S is slightly more evolved than G108-N, in the consideration of the CO depletion factor, molecular abundances, and association with infrared sources. G108-S seems to be affected by the compression from Sh2-152, while G108-N is relatively protected from the external effect

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Jungha Kim, Jeong-Eun Lee, Tie Liu, Kee-Tae Kim, Yuefang Wu, Ken'ichi Tatematsu, Sheng-Yuan Liu, JCMT Large Program "SCOPE" collaboration, TRAO Key Science Program "TOP" collaboration. 2017-07-02. Star formation conditions in a Planck Galactic Cold Clump, G108.84-00.81. https://doi.org/10.3847/1538-4365%2Faa7b31

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