Discovery of large-scale gravitational infall in a massive protostellar cluster

作者：Barnes Peter J^*; Yonekura Yoshinori; Ryder Stuart D; Hopkins Andrew M; Miyamoto Yosuke; Furukawa Naoko; Fukui Yasuo

来源：Monthly Notices of the Royal Astronomical Society, 2010, 402(1): 73-86.

DOI：10.1111/j.1365-2966.2009.15890.x

• astrochemistry
• stars: formation
• ISM: kinematics and dynamics
• ISM: molecules
• infrared: ISM
• radio lines: ISM

We report Mopra Australia Telescope National Facility (ATNF), Anglo-Australian Telescope and Atacama Submillimeter Telescope Experiment observations of a molecular clump in Carina, BYF73 = G286.21+0.17, which give evidence of large-scale gravitational infall in the dense gas. From the millimetre and far-infrared data, the clump has a mass of similar to 2 x 104 M(circle dot), luminosity of similar to 2-3 x 104 L(circle dot) and diameter of similar to 0.9 pc. From radiative transfer modelling, we derive a mass infall rate of similar to 3.4 x 10-2 M(circle dot) yr-1. If confirmed, this rate for gravitational infall in a molecular core or clump may be the highest yet seen. The near-infrared K-band imaging shows an adjacent compact H ii region and IR cluster surrounded by a shell-like photodissociation region showing H(2) emission. At the molecular infall peak, the K imaging also reveals a deeply embedded group of stars with associated H(2) emission. The combination of these features is very unusual, and we suggest that they indicate the ongoing formation of a massive star cluster. We discuss the implications of these data for competing theories of massive star formation.

• 出版日期2010-2-11