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

Here we present deep (16 μJy beam), 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 rad...

Descripción completa

Detalles Bibliográficos
Autores: Girart, Josep Miquel, Fernández-López, Manuel, Li, Zhi-Yun, Yang, H., Estalella, Robert, Anglada Pons, Guillem Josep, Añez-López, N., Busquet, Gemma, Carrasco-González, Carlos, Curiel, Salvador, Galván-Madrid, Roberto, Gómez, José F., de Gregorio-Monsalvo, Itziar, Jiménez-Serra, Izaskun, Krasnopolsky, R., Martí, Josep, Osorio, Mayra, Padovani, Marco, Rao, Ramprasad, Rodríguez, Luis F., Torrelles, José M.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/214128
Acceso en línea:http://hdl.handle.net/10261/214128
Access Level:acceso abierto
Palabra clave:Accretion, accretion disks
ISM:individual objects (GGD27, HH 80-81, IRAS 18162-2048)
Stars:formation
Descripción
Sumario:Here we present deep (16 μJy beam), 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 μm. 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.© 2018. The American Astronomical Society. All rights reserved..

Similares en LA Referencia