Rotating Motion of the Outflow of IRAS 16293-2422 A1 at Its Origin Point Near the Protostar

Yoko Oya , Yoshimasa Watanabe , Ana López-Sepulcre (1) , Cecilia Ceccarelli (1) , Bertrand Lefloch (1) , Cécile Favre (1) , Satoshi Yamamoto

1 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble

The Class 0 protostar IRAS 16293-2422 Source A is known to be a binary system (A1 and A2) or even a multiple system that processes a complex outflow structure. We have observed this source in the C³⁴S, SO, and OCS lines at 3.1 mm with the Atacama Large Millimeter/submillimeter Array. A substructure of this source is traced by our high angular-resolution observation (0"12; 20 au) of the continuum emission. The northwest-southeast (NW-SE) outflow on a 2″ scale is detected in the SO (J_N = 2₂-1₁) line. Based on the morphology of the SO distribution, this bipolar outflow structure seems to originate from the protostar A1 and its circumstellar disk, or the circummultiple structure of Source A. The rotation motion of the NW-SE outflow is detected in the SO and OCS emissions. We evaluate the specific angular momentum of the outflowing gas to be (8.6-14.3) × 10^-4 km s^-1 pc. If the driving source of this outflow is the protostar A1 and its circumstellar disk, it can be a potential mechanism to extract the specific angular momentum of the disk structure. These results can be a hint for the outflow launching mechanism in this source. Furthermore, they provide us with an important clue to resolve the complicated structure of IRAS 16293-2422 Source A.

Keywords: Interstellar medium; Protostars; Low mass stars; Stellar jets

Domains: Sciences of the Universe [physics]; Astrophysics [astro-ph]

Yoko Oya, Yoshimasa Watanabe, Ana López-Sepulcre, Cecilia Ceccarelli, Bertrand Lefloch, et al.. Rotating Motion of the Outflow of IRAS 16293-2422 A1 at Its Origin Point Near the Protostar. The Astrophysical Journal, 2021, 921, ⟨10.3847/1538-4357/ac0a72⟩. ⟨insu-03705264⟩