Details

Autor(en) / Beteiligte

• Girart, J. M.
• Fernández-López, M.
• Li, Z.-Y.
• Yang, H.
• Estalella, R.
• Anglada, G.
• Áñez-López, N.
• Busquet, G.
• Carrasco-González, C.
• Curiel, S.
• Galvan-Madrid, R.
• Gómez, J. F.
• Gregorio-Monsalvo, I. de
• Jiménez-Serra, I.
• Krasnopolsky, R.
• Martí, J.
• Osorio, M.
• Padovani, M.
• Rao, R.
• Rodríguez, L. F.
• Torrelles, J. M.

Titel

Resolving the Polarized Dust Emission of the Disk around the Massive Star Powering the HH 80-81 Radio Jet

Ist Teil von

• Astrophysical journal. Letters, 2018-04, Vol.856 (2), p.L27

Ort / Verlag

Austin: The American Astronomical Society

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Here we present deep (16 Jy beam−1), very high (40 mas) angular resolution 1.14 mm, polarimetric, Atacama Large Millimeter/submillimeter Array (ALMA) observations toward the massive protostar driving the HH 80-81 radio jet. The observations clearly resolve the disk oriented perpendicularly to the radio jet, with a radius of 0 171 (∼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 (∼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 m. 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 the 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.