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arXiv · 2409.05492

JCMT 850 $\micron$ continuum observations of density structures in the G35 molecular complex

Abstract

Filaments are believed to play a key role in high-mass star formation. We present a systematic study of the filaments and their hosting clumps in the G35 molecular complex using JCMT SCUBA-2 850 $\micron$ continuum data. We identified five clouds in the complex and 91 filaments within them, some of which form 10 hub-filament systems (HFSs), each with at least 3 hub-composing filaments. We also compiled a catalogue of 350 dense clumps, 183 of which are associated with the filaments. We investigated the physical properties of the filaments and clumps, such as mass, density, and size, and their relation to star formation. We find that the global mass-length trend of the filaments is consistent with a turbulent origin, while the hub-composing filaments of high line masses ($m_{\rm l}\,>$\,230\,$\mathrm{M_{\odot}~pc^{-1}}$) in HFSs deviate from this relation, possibly due to feedback from massive star formation. We also find that the most massive and densest clumps (R\,$>$\,0.2\,pc, M\,$>35\,\mathrm{M_{\odot}}$, $\mathrm{\Sigma}>\,0.05\,\mathrm{g~cm^{-2}}$) are located in the filaments and in the hubs of HFS with the latter bearing a higher probability of occurrence of high-mass star-forming signatures, highlighting the preferential sites of HFSs for high-mass star formation. We do not find significant variation in the clump mass surface density across different evolutionary environments of the clouds, which may reflect the balance between mass accretion and stellar feedback.

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Xianjin Shen, Hong-Li Liu, Zhiyuan Ren, Anandmayee Tej, Di Li, Hauyu Baobab Liu, Gary A. Fuller, Jinjin Xie, Sihan Jiao, Aiyuan Yang, Patrick M. Koch, Fengwei Xu, Patricio Sanhueza, Pham N. Diep, Nicolas Peretto, Ram K. Yadav, Busaba H. Kramer, Koichiro Sugiyama, Mark Rawlings, Chang Won Lee, Ken'ichi Tatematsu, Daniel Harsono, David Eden, Woojin Kwon, Chao-Wei Tsai, Glenn White, Kee-Tae Kim, Tie Liu, Ke Wang, Siju Zhang, Wenyu Jiao, Dongting Yang, Das R. Swagat, Jingwen Wu, Chen Wang. 2024-09-09. JCMT 850 $\micron$ continuum observations of density structures in the G35 molecular complex. https://arxiv.org/abs/2409.05492

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