SAI Jinshi, D1 at the University of Tokyo(Supervisor: OHASHI Nagayoshi,,)
Disk Structures around the Class I Protostar L1489 IRS Revealed by ALMA
We observed a Class I protostar, L1489 IRS with ALMA at high spatial resolutions of ~0.3” in ALMA Band 6 (230 GHz). Our new observations in C18O 2-1 emission allowed us to confirm that the Keplerian disk extends to ~600 au in radius. We also found a gap structure at a radius ~200-300 au on a disk in C18O 2-1, and that the gas disk of L1489 IRS consists of two disks, an inner disk extending to ~200 au and an outer disk extending to ~300-600 au in radius. Furthermore, it was found that the inner disk and outer disk are misaligned by ~15 deg by comparison between observations and a kinematic model of a Keplerian disk. This misaligned disk system suggests that the axis of angular momentum of an accretion changes its direction during the star and circumstellar disk formation process. 1.3 mm dust continuum extends to ~ 370 au continuously however a gap structure is seen in C18O. It infers that the gap in C18O is due to CO depletion but the origin of the C18O gas gap is still on debated.
Jungha Kim, SOKENDAI 4th year (D2)(Supervisor: Mareki Honma,Tomoya Hirota,Katsunori Shibata)
Dynamics of jets/outflows from high-mass young stellar objects revealed by KaVA and ALMA observations