Context. Large cavities in disks are important testing grounds for the mechanisms proposed to drive disk evolution and dispersion, such as dynamical clearing by planets and photoevaporation.
Aims: We aim to resolve the large cavity in the disk around HD 34282, whose presence has been predicted by previous studies modeling the spectral energy distribution of the disk.
Methods: Using ALMA band 7 observations we studied HD 34282 with a spatial resolution of 0.10″ × 0.17'' at 345 GHz.
Results: We resolve the disk around HD 34282 into a ring between 0.24'' and 1.15'' (78 and 374 au adopting a distance of 325 pc). The emission in this ring shows azimuthal asymmetry centered at a radial distance of 0.46'' and a position angle of 135° and an azimuthal FWHM of 51°. We detect CO emission both inside the disk cavity and as far out as 2.7 times the radial extent of the dust emission.
Conclusions: Both the large disk cavity and the azimuthal structure in the disk around HD 34282 can be explained by the presence of a 50 Mjup brown dwarf companion at a separation of ≈0.1''.
Astronomy and Astrophysics
- Pub Date:
- November 2017
- stars: variables: T Tauri;
- Herbig Ae/Be;
- protoplanetary disks;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- 9 pages, 8 figures. Accepted in A&