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We present the results of the observations made within the ALMA Large Program called Early Planet Formation in Embedded disks of the Class 0 protostar GSS30 IRS3. Our observations included the 1.3 mm continuum with a resolution of 0″.05 (7.8 au) and several molecular species, including12CO,13CO, C18O, H2CO, and c-C3H2. The dust continuum analysis unveiled a disk-shaped structure with a major axis of ~200 au. We observed an asymmetry in the minor axis of the continuum emission suggesting that the emission is optically thick and the disk is flared. On the other hand, we identified two prominent bumps along the major axis located at distances of 26 and 50 au from the central protostar. The origin of the bumps remains uncertain and might be an embedded substructure within the disk or the temperature distribution and not the surface density because the continuum emission is optically thick. The12CO emission reveals a molecular outflow consisting of three distinct components: a collimated component, an intermediate-velocity component exhibiting an hourglass shape, and a wider angle low-velocity component. We associate these components with the coexistence of a jet and a disk wind. The C18O emission traces both a circumstellar disk in Keplerian rotation and the infall of the rotating envelope. We measured a stellar dynamical mass of 0.35 ±0.09 M⊙.
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Early Planet Formation in Embedded Disks (eDisk). V. Possible Annular Substructure in a Circumstellar Disk in the Ced110 IRS4 System
Abstract We have observed the Class 0/I protostellar system Ced110 IRS4 at an angular resolution of 0.″05 (∼10 au) as part of the Atacama Large Millimeter/submillimeter Array large program, Early Planet Formation in Embedded Disks. The 1.3 mm dust continuum emission reveals that Ced110 IRS4 is a binary system with a projected separation of ∼250 au. The continuum emissions associated with the main source and its companion, named Ced110 IRS4A and IRS4B, respectively, exhibit disk-like shapes and likely arise from dust disks around the protostars. The continuum emission of Ced110 IRS4A has a radius of ∼110 au (∼0.″6) and shows bumps along its major axis with an asymmetry. The bumps can be interpreted as a shallow, ring-like structure at a radius of ∼40 au (∼0.″2) in the continuum emission, as demonstrated from two-dimensional intensity distribution models. A rotation curve analysis on the C18O and13COJ= 2–1 lines reveals the presence of a Keplerian disk within a radius of 120 au around Ced110 IRS4A, which supports the interpretation that the dust continuum emission arises from a disk. The ring-like structure in the dust continuum emission might indicate a possible annular substructure in the surface density of the embedded disk, although the possibility that it is an apparent structure due to the optically thick continuum emission cannot be ruled out.
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- PAR ID:
- 10445905
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 954
- Issue:
- 1
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 67
- Size(s):
- Article No. 67
- Sponsoring Org:
- National Science Foundation
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