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arXiv · 2206.08505

ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- XI. From inflow to infall in hub-filament systems

Jian-Wen Zhou·Tie Liu·Neal J. Evans II·Guido Garay·Paul F. Goldsmith·Gilberto C. Gomez·Enrique Vazquez-Semadeni·Hong-Li Liu·Amelia M. Stutz·Ke Wang·Mika Juvela·Jinhua He·Di Li·Leonardo Bronfman·Xunchuan Liu·Feng-Wei Xu·Anandmayee Tej·L. K. Dewangan·Shanghuo Li·Siju Zhang·Chao Zhang·Zhiyuan Ren·Kenichi Tatematsu·Pak Shing Li·Chang Won Lee·Tapas Baug·Sheng-Li Qin·Yuefang Wu·Yaping Peng·Yong Zhang·Rong Liu·Qiu-Yi Luo·Jixing Ge·Anindya Saha·Eswaraiah Chakali·Qizhou zhang·Kee-Tae Kim·Isabelle Ristorcelli·Zhi-Qiang Shen·Jin-Zeng Li
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Abstract

We investigate the presence of hub-filament systems in a large sample of 146 active proto-clusters, using H$^{13}$CO$^{+}$ J=1-0 molecular line data obtained from the ATOMS survey. We find that filaments are ubiquitous in proto-clusters, and hub-filament systems are very common from dense core scales ($\sim$0.1 pc) to clump/cloud scales ($\sim$1-10 pc). The proportion of proto-clusters containing hub-filament systems decreases with increasing dust temperature ($T_d$) and luminosity-to-mass ratios ($L/M$) of clumps, indicating that stellar feedback from H{\sc ii} regions gradually destroys the hub-filament systems as proto-clusters evolve. Clear velocity gradients are seen along the longest filaments with a mean velocity gradient of 8.71 km s$^{-1}$pc$^{-1}$ and a median velocity gradient of 5.54 km s$^{-1}$pc$^{-1}$. We find that velocity gradients are small for filament lengths larger than $\sim$1~pc, probably hinting at the existence of inertial inflows, although we cannot determine whether the latter are driven by large-scale turbulence or large-scale gravitational contraction. In contrast, velocity gradients below $\sim$1~pc dramatically increase as filament lengths decrease, indicating that the gravity of the hubs or cores starts to dominate gas infall at small scales. We suggest that self-similar hub-filament systems and filamentary accretion at all scales may play a key role in high-mass star formation.

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Jian-Wen Zhou, Tie Liu, Neal J. Evans II, Guido Garay, Paul F. Goldsmith, Gilberto C. Gomez, Enrique Vazquez-Semadeni, Hong-Li Liu, Amelia M. Stutz, Ke Wang, Mika Juvela, Jinhua He, Di Li, Leonardo Bronfman, Xunchuan Liu, Feng-Wei Xu, Anandmayee Tej, L. K. Dewangan, Shanghuo Li, Siju Zhang, Chao Zhang, Zhiyuan Ren, Kenichi Tatematsu, Pak Shing Li, Chang Won Lee, Tapas Baug, Sheng-Li Qin, Yuefang Wu, Yaping Peng, Yong Zhang, Rong Liu, Qiu-Yi Luo, Jixing Ge, Anindya Saha, Eswaraiah Chakali, Qizhou zhang, Kee-Tae Kim, Isabelle Ristorcelli, Zhi-Qiang Shen, Jin-Zeng Li. 2022-06-17. ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- XI. From inflow to infall in hub-filament systems. https://doi.org/10.1093/mnras%2Fstac1735

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