Oral Presentation

eDisk: A Compact but Structured Keplerian Disk and Large-scale Spiral Structures Revealed in the Class I Protostellar System IRAS 04169+2702

Author(s): Ilseung Han (UST/KASI), Woojin Kwon (SNU), and the eDisk team

Presenter: Ilseung Han (UST/KASI)

We present the first-look results of high-resolution (up to 0.05′′) dust continuum and molecular line observations toward the Class I protostellar system IRAS 04169+2702 in the Taurus B213 region (d = 156 pc), as part of the ALMA Cycle 7 Large Program Early Planet Formation in Embedded Disks (eDisk). The 1.3-mm dust continuum emission reveals a compact (R ∼ 17 au) but structured disk: two local peaks in the inner region and small bumps in the outer region. Velocity gradients along the disk major axis, which is perpendicular to the bipolar outflow, are seen in the C18O (2−1), 13CO (2−1), and 12CO (2−1) emissions. The position-velocity diagrams of these line emissions demonstrate that 12CO identifies a Keplerian disk, while an inner envelope traced by C18O and 13CO is infalling in conservation of angular momentum. In addition to the compact disk, a 600 au-sized spiral structure is revealed in the dust continuum image. Much larger-scale spiral structures are also clearly detected in the C18O (2−1), 13CO (2−1), SO (65−54), and H2CO (30,3−20,2) emissions.