High-angular resolution observations of protoplanetary disks around young and…evolved stars

Séminaire IPAG de Jacques Kluska (KU Leuven), jeudi 21 mars 2019 à 11h00, salle Manuel Forestini

Protoplanetary disks are a byproduct of star formation and are the birth places of future planetary systems. However, besides young stars there are other objects that are surrounded by very similar disks of dust and gas : the post-AGB binaries. Despite very different formation processes, the circumbinary disks around those evolved binaries have a similar infrared excess to disks around young stars, a Keplerian rotation profile and evidence of dust processing. Altogether, those similarities rise the exciting question of planet formation at the other end of the Hertzsprung-Russel diagram.

My talk will therefore be split in two parts. In the first part I will present the morphology of the dust sublimation region of protoplanetary disks around young stars as seen from reconstructed images from the VLTI/PIONIER large programme. I will also focus on one target from this survey presenting an unusually large near-infrared emission, discovered during an observing campaign (direct imaging, aperture masking and long baseline interferometry) to understand its structure. The resulting picture of this object points towards early stages of disk dissipation.

In the second part I will present the inner regions of disks around post-AGB binaries as seen by PIONIER. The first image and the first interferometric systematic study of the inner disk rims of those systems show that the disks are ruled by dust sublimation physics just as in young stars. I will show the differences and similarities between both type of targets. To end, I will introduce the VLTI imaging large programme (called INSPIRING) that will uncover more details of disks around post-AGB binaries.