Gas Accretion within the Dust Cavity in AB Aur
Journal article, 2019

AB Aur is a Herbig Ae star hosting a well-known transitional disk. Because of its proximity and low inclination angle, it is an excellent object to study planet formation. Our goal is to investigate the chemistry and dynamics of the molecular gas component in the AB Aur disk, and its relation with the prominent horseshoe shape observed in continuum mm emission. We used the Northern Extended Milimeter Array interferometer to map with high angular resolution the J = 3-2 lines of HCO+ and HCN. By combining both, we can gain insight into the AB Aur disk structure. Chemical segregation is observed in the AB Aur disk: HCO+ shows intense emission toward the star position, at least one bright molecular bridge within the dust cavity, and ring-like emission at larger radii, while HCN is only detected in an annular ring that is coincident with the dust ring and presents an intense peak close to the dust trap. We use HCO+ to investigate the gas dynamics inside the cavity. The observed bright HCO+ bridge connects the compact central source with the outer dusty ring. This bridge can be interpreted as an accretion flow from the outer ring to the inner disk/jet system proving gas accretion through the cavity.

disk interactions

planet

planets and satellites: formation

circumstellar matter

protoplanetary disks

stars: individual (AB Auriga)

stars: pre-main sequence

Author

Pablo Riviere-Marichalar

Spanish National Observatory (OAN)

Asuncion Fuente

Spanish National Observatory (OAN)

Clement Baruteau

Centre national de la recherche scientifique (CNRS)

Roberto Neri

Institut de RadioAstronomie Millimetrique (IRAM)

Sandra Treviño Morales

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics

Andres Carmona

Centre national de la recherche scientifique (CNRS)

Marcelino Agundez

Consejo Superior de Investigaciones Científicas

Rafael Bachiller

Spanish National Observatory (OAN)

Astrophysical Journal Letters

2041-8205 (ISSN) 2041-8213 (eISSN)

Vol. 879 1 L14

Subject Categories

Astronomy, Astrophysics and Cosmology

DOI

10.3847/2041-8213/ab289d

More information

Latest update

10/14/2019