Bibliographic Details
| Title: |
Resolving the polarized dust emission of the disk around the massive star powering the HH~80-81 radio jet |
| Authors: |
Girart, J. M., Fernandez-Lopez, M., Li, Z. -Y., Yang, H., Estalella, R., Anglada, G., Añez-Lopez, N., Busquet, G., Carrasco-Gonzalez, C., Curiel, S., Galvan-Madrid, R., Gomez, J. F., de Gregorio-Monsalvo, I., Jimenez-Serra, I., Krasnopolsky, R., Marti, J., Osorio, M., Padovani, M., Rao, R., Rodriguez, L. F., Torrelles, J. M. |
| Publication Year: |
2018 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - Solar and Stellar Astrophysics, Astrophysics - Astrophysics of Galaxies |
| More Details: |
Here we present deep (16 mumJy), very high (40 mas) angular resolution 1.14 mm, polarimetric, Atacama Large Millimeter/submillimeter Array (ALMA) observations towards the massive protostar driving the HH 80-81 radio jet. The observations clearly resolve the disk oriented perpendicular to the radio jet, with a radius of ~0.171 arcsec (~291 au at 1.7 kpc distance). The continuum brightness temperature, the intensity profile, and the polarization properties clearly indicate that the disk is optically thick for a radius of R<170 au. The linear polarization of the dust emission is detected almost all along the disk and its properties suggest that dust polarization is produced mainly by self-scattering. However, the polarization pattern presents a clear differentiation between the inner (optically thick) part of the disk and the outer (optically thin) region of the disk, with a sharp transition that occurs at a radius of 0.1 arcsec (~170 au). The polarization characteristics of the inner disk suggest that dust settling has not occurred yet with a maximum dust grain size between 50 and 500 mum. The outer part of the disk has a clear azimuthal pattern but with a significantly higher polarization fraction compared to the inner disk. This pattern is broadly consistent with self-scattering of a radiation field that is beamed radially outward, as expected in the optically thin outer region, although contribution from non-spherical grains aligned with respect to the radiative flux cannot be excluded.
Comment: Accepted for publication in the Astrophysical Journal Letters |
| Document Type: |
Working Paper |
| DOI: |
10.3847/2041-8213/aab76b |
| Access URL: |
http://arxiv.org/abs/1803.06165 |
| Accession Number: |
edsarx.1803.06165 |
| Database: |
arXiv |
