2018/02/11 by Chin-Fei Lee, Zhi-Yun Li, Claudio Codella +7 · 1 citation
Physics and Astronomy · #Angular momentum #Astro and Planetary Science #Astrophysics and Star Formation Studies #Bipolar outflow #Collimated light #Jet (fluid) #Outflow #Rotation (mathematics) #Shell (structure) #Stellar, planetary, and galactic studies #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/aaae6d
29 pages, 11 figures
arxiv created 2018/02/11 · openalex created_date 2018/02/23 · openalex publication_date 2018/03/20 · arxiv updated 2018/04/04 · openalex updated_date 2026/08/06
Abstract HH 212 is a Class 0 protostellar system found to host a “hamburger”-shaped dusty disk with a rotating disk atmosphere and a collimated SiO jet at a distance of ∼400 pc. Recently, a compact rotating outflow has been detected in SO and SO 2 toward the center along the jet axis at ∼52 au (0.″13) resolution. Here we resolve the compact outflow into a small-scale wide-opening rotating outflow shell and a collimated jet, with the observations in the same S-bearing molecules at ∼16 au (0.″04) resolution. The collimated jet is aligned with the SiO jet, tracing the shock interactions in the jet. The wide-opening outflow shell is seen extending out from the inner disk around the SiO jet and has a width of ∼100 au. It is not only expanding away from the center, but also rotating around the jet axis. The specific angular momentum of the outflow shell is ∼40 au km s −1 . Simple modeling of the observed kinematics suggests that the rotating outflow shell can trace either a disk wind or disk material pushed away by an unseen wind from the inner disk or protostar. We also resolve the disk atmosphere in the same S-bearing molecules, confirming the Keplerian rotation there.