Direct Observational Evidence of the Multi-scale, Dynamical Mass Accretion Toward a High-mass Star-forming Hub-filament System

Abstract

There is growing evidence that high-mass star formation and hub-filament systems (HFS) are intricately linked. The gas kinematics along the filaments and the forming high-mass star(s) in the central hub are in excellent agreement with the new generation of global hierarchical high-mass star formation models. In this paper, we present an observational investigation of a typical HFS cloud, G310.142+0.758 (G310 hereafter), which reveals unambiguous evidence of mass inflow from the cloud scale via the filaments onto the forming protostar(s) at the hub conforming with the model predictions. Continuum and molecular line data from the ATOMS and MALT90 surveys that cover different spatial scales are used. Three filaments (with a total mass of 5.7 ± 1.1 × 10 ^3 M _⊙ ) are identified converging toward the central hub region where several signposts of high-mass star formation have been observed. The hub region contains a massive clump (1280 ± 260 M _⊙ ) harboring a central massive core. Additionally, five outflow lobes are associated with the central massive core implying a forming cluster. The observed large-scale, smooth, and coherent velocity gradients from the cloud down to the core scale, and the signatures of infall motion seen in the central massive clump and core, clearly unveil a nearly continuous, multi-scale mass accretion/transfer process at a similar mass infall rate of ∼10 ^−3 M _⊙ yr ^−1 over all scales, feeding the central forming high-mass protostar(s) in the G310 HFS cloud.

Keywords

• Star forming regions
• Molecular clouds
• Infrared dark clouds
• Young stellar objects
• Molecular gas
• Dust continuum emission