| Full text | |
| Author(s): |
Navarete, F.
;
Damineli, A.
;
Steiner, J. E.
;
Blum, R. D.
Total Authors: 4
|
| Document type: | Journal article |
| Source: | Monthly Notices of the Royal Astronomical Society; v. 503, n. 1, p. 22-pg., 2021-03-12. |
| Abstract | |
W33A is a well-known example of a high-mass young stellar object showing evidence of a circumstellar disc. We revisited the K-band NIFS/Gemini North observations of the W33A protostar using principal components analysis tomography and additional post-processing routines. Our results indicate the presence of a compact rotating disc based on the kinematics of the CO absorption features. The position-velocity diagram shows that the disc exhibits a rotation curve with velocities that rapidly decrease for radii larger than 0.1 arcsec (similar to 250 au) from the central source, suggesting a structure about four times more compact than previously reported. We derived a dynamical mass of 10.0(-2.2)(+4.1) M-circle dot for the 'disc + protostar' system, about similar to 33 per cent smaller than previously reported, but still compatible with high-mass protostar status. A relatively compact H-2 wind was identified at the base of the large-scale outflow of W33A, with a mean visual extinction of similar to 63 mag. By taking advantage of supplementary near-infrared maps, we identified at least two other point-like objects driving extended structures in the vicinity of W33A, suggesting that multiple active protostars are located within the cloud. The closest object (Source B) was also identified in the NIFS field of view as a faint point-like object at a projected distance of similar to 7000 au from W33A, powering extended K-band continuum emission detected in the same field. Another source (Source C) is driving a bipolar H-2 jet aligned perpendicular to the rotation axis of W33A. (AU) | |
| FAPESP's process: | 19/02029-2 - Eta Carinae: a perfect periastron passage in 2020 |
| Grantee: | Augusto Damineli Neto |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 17/18191-8 - High-mass star formation: the mass of the central sources and the physics of the accretion process |
| Grantee: | Felipe Donizeti Teston Navarete |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |