Evidence of high-mass star formation through multi-scale mass accretion in hub-filament-system clouds

Hong-Li Liu, Anandmayee Tej, Tie Liu, Patricio Sanhueza, Shengli Qin, Jinhua He, Paul F. Goldsmith, Guido Garay, Sirong Pan, Kaho Morii, Shanghuo Li, Amelia Stutz, Keníchi Tatematsu, Feng-Wei Xu, Leonardo Bronfman, Anindya Saha, Namitha Issac, Tapas Baug, L. Viktor Toth, Lokesh Dewangan, Ke Wang, Jianwen Zhou, Chang Won Lee, Dongting Yang, Anxu Luo, Xianjin Shen, Yong Zhang, Yue-Fang Wu, Zhiyuan Ren, Xun-Chuan Liu, Archana Soam, Siju Zhang, Qiu-Yi Luo

Published 2023-01-09Version 1

We present a statistical study of a sample of 17 hub-filament-system (HFS) clouds of high-mass star formation using high-angular resolution ($\sim$1-2 arcsecond) ALMA 1.3mm and 3mm continuum data. The sample includes 8 infrared (IR)-dark and 9 IR-bright types, which correspond to an evolutionary sequence from the IR-dark to IR-bright stage. The central massive clumps and their associated most massive cores are observed to follow a trend of increasing mass ($M$) and mass surface density ($\Sigma$) with evolution from IR-dark to IR-bright stage. In addition, a mass-segregated cluster of young stellar objects (YSOs) are revealed in both IR-dark and IR-bright HFSs with massive YSOs located in the hub and the population of low-mass YSOs distributed over larger areas. Moreover, outflow feedback in all HFSs are found to escape preferentially through the inter-filamentary diffuse cavities, suggesting that outflows would render a limited effect on the disruption of the HFSs and ongoing high-mass star formation therein. From the above observations, we suggest that high-mass star formation in the HFSs can be described by a multi-scale mass accretion/transfer scenario, from hub-composing filaments through clumps down to cores, that can naturally lead to a mass-segregated cluster of stars.