Imaging a Central Ionized Component, a Narrow Ring, and the CO Snowline in the Multigapped Disk of HD 169142

DOI: 
10.3847/1538-4357/aa6620
Publication date: 
01/04/2017
Main author: 
Macías, Enrique
IAA authors: 
Macías, Enrique;Anglada, Guillem;Osorio, Mayra;Gómez, José F.
Authors: 
Macías, Enrique;Anglada, Guillem;Osorio, Mayra;Torrelles, José M.;Carrasco-González, Carlos;Gómez, José F.;Rodríguez, Luis F.;Sierra, Anibal
Journal: 
The Astrophysical Journal
Refereed: 
Yes
Publication type: 
Article
Volume: 
838
Pages: 
97
Abstract: 

We report Very Large Array observations at 7 mm, 9 mm, and 3 cm toward the pre-transitional disk of the Herbig Ae star HD 169142. These observations have allowed us to study the millimeter emission of this disk with the highest angular resolution so far (0.″12 × 0.″09, or 14 au × 11 au, at 7 mm). Our 7 and 9 mm images show a narrow ring of emission at a radius of ∼25 au tracing the outer edge of the inner gap. This ring presents an asymmetric morphology that could be produced by dynamical interactions between the disk and forming planets. Additionally, the azimuthally averaged radial intensity profiles of the 7 and 9 mm images confirm the presence of the previously reported gap at ∼45 au and reveal a new gap at ∼85 au. We analyzed archival DCO<SUP>+</SUP>(3─2) and C<SUP>18</SUP>O(2─1) ALMA observations, showing that the CO snowline is located very close to this third outer gap. This suggests that growth and accumulation of large dust grains close to the CO snowline could be the mechanism responsible for this proposed outer gap. Finally, a compact source of emission is detected at 7 mm, 9 mm, and 3 cm toward the center of the disk. Its flux density and spectral index indicate that it is dominated by free─free emission from ionized gas, which could be associated with the photoionization of the inner disk, an independent object, or an ionized jet.

Database: 
ADS
SCOPUS
URL: 
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85017308812&doi=10.3847%2f1538-4357%2faa6620&partnerID=40&md5=4a952f5f7f1096fddbd339d1c1b8d3e6
ADS Bibcode: 
2017ApJ...838...97M
Keywords: 
ISM: jets and outflows;planet─disk interactions;protoplanetary disks;stars: individual: HD 169142;stars: pre-main sequence;Astrophysics - Solar and Stellar Astrophysics;Astrophysics - Earth and Planetary Astrophysics