TY - JOUR
T1 - Formation of the SDC13 Hub-filament System
T2 - A Cloud–Cloud Collision Imprinted on the Multiscale Magnetic Field
AU - Wang, Jia-Wei
AU - Koch, Patrick M.
AU - Tang, Ya-Wen
AU - Fuller, Gary A.
AU - Peretto, Nicolas
AU - Williams, Gwenllian M.
AU - Yen, Hsi-Wei
AU - Lee, Han-Tsung
AU - Chen, Wei-An
N1 - Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/6/1
Y1 - 2022/6/1
N2 - Hub-filament systems (HFSs) are potential sites of protocluster and massive star formation, and play a key role in mass accumulation. We report JCMT POL-2 850 μm polarization observations toward the massive HFS SDC13. We detect an organized magnetic field near the hub center with a cloud-scale "U-shape" morphology following the western edge of the hub. Together with larger-scale APEX 13CO and PLANCK polarization data, we find that SDC13 is located at the convergent point of three giant molecular clouds (GMCs) along a large-scale, partially spiral-like magnetic field. The smaller "U-shape" magnetic field is perpendicular to the large-scale magnetic field and the converging GMCs. We explain this as the result of a cloud–cloud collision. Within SDC13, we find that local gravity and velocity gradients point toward filament ridges and hub center. This suggests that gas can locally be pulled onto filaments and overall converges to the hub center. A virial analysis of the central hub shows that gravity dominates the magnetic and kinematic energy. Combining large- and small-scale analyses, we propose that SDC13 is initially formed from a collision of clouds moving along the large-scale magnetic field. In the post-shock regions, after the initial turbulent energy has dissipated, gravity takes over and starts to drive the gas accretion along the filaments toward the hub center.
AB - Hub-filament systems (HFSs) are potential sites of protocluster and massive star formation, and play a key role in mass accumulation. We report JCMT POL-2 850 μm polarization observations toward the massive HFS SDC13. We detect an organized magnetic field near the hub center with a cloud-scale "U-shape" morphology following the western edge of the hub. Together with larger-scale APEX 13CO and PLANCK polarization data, we find that SDC13 is located at the convergent point of three giant molecular clouds (GMCs) along a large-scale, partially spiral-like magnetic field. The smaller "U-shape" magnetic field is perpendicular to the large-scale magnetic field and the converging GMCs. We explain this as the result of a cloud–cloud collision. Within SDC13, we find that local gravity and velocity gradients point toward filament ridges and hub center. This suggests that gas can locally be pulled onto filaments and overall converges to the hub center. A virial analysis of the central hub shows that gravity dominates the magnetic and kinematic energy. Combining large- and small-scale analyses, we propose that SDC13 is initially formed from a collision of clouds moving along the large-scale magnetic field. In the post-shock regions, after the initial turbulent energy has dissipated, gravity takes over and starts to drive the gas accretion along the filaments toward the hub center.
UR - http://www.scopus.com/inward/record.url?scp=85131693128&partnerID=8YFLogxK
U2 - 10.3847/1538-4357/ac6872
DO - 10.3847/1538-4357/ac6872
M3 - Article
SN - 0004-637X
VL - 931
JO - The Astrophysical Journal
JF - The Astrophysical Journal
IS - 2
M1 - 115
ER -