Evidence of high-mass star formation through multiscale mass accretion in hub-filament-system clouds
Zhang, Yong; Sanhueza, Patricio; Tej, Anandmayee; Soam, Archana; Lee, Chang Won; Liu, Hong-Li; Liu, Tie; Li, Shanghuo; Wang, Ke; Qin, Sheng-Li; Garay, Guido; Tatematsu, Ken'ichi; Ren, Zhiyuan; Dewangan, Lokesh; Saha, Anindya; Morii, Kaho; Goldsmith, Paul F.; Xu, Feng-Wei; Bronfman, Leonardo; He, Jinhua; Toth, L. Viktor; Issac, Namitha; Baug, Tapas; Stutz, Amelia; Wu, Yue-Fang; Pan, Sirong; Zhang, Siju; Zhou, Jianwen; Yang, Dongting; Shen, Xianjin; Luo, Anxu; Liu, Xun-Chuan; Luo, Qiu-Yi
China, India, Japan, Chile, United States, Germany, Hungary, South Korea
Abstract
We present a statistical study of a sample of 17 hub-filament-system (HFS) clouds of high-mass star formation using high-angular resolution (~1-2 arcsec) ALMA 1.3 and 3 mm continuum data. The sample includes eight infrared (IR)-dark and nine 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 (Σ) with evolution from the 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 multiscale mass accretion/transfer scenario, from hub-composing filaments through clumps down to cores, which can naturally lead to a mass-segregated cluster of stars.