Dr. Ruobing Dong

University of Florida Astronomy Colloquium - April 1st, 2015

Gaps, Spiral Arms, and Asymmetries in Protoplanetary Disks: Signposts of Planets?

The conventional wisdom is that planets form in protoplanetary disks. Directly detecting forming planets in disks is the most direct way to determine the time and location of planet formation; however this has been very difficult. On the other hand, theory and simulations have shown that planets can perturb the disk and excite structures such as spiral arms, gaps, vortexes, and other asymmetric features. Recently, thanks to the advanced instruments that have come online in the past few years, a rich gallery of disk features has been revealed in spatially resolved disk observations taken by ALMA, Subaru, and VLT at both submm and NIR wavelengths. It is widely speculated that these features are created by currently unseen planets embedded in disks. I will review recent progress in the field of resolved disk observations; and discuss some of the latest disk modeling efforts, in which we combine hydrodynamical and radiative transfer simulations to study the observational signatures of planet-induced features. Results have shown that the morphology of planet-opened gaps are broadly consistent with the observed gaps in both traditional disks and the HL Tau system, while the origins of the spiral arms and azimuthal asymmetries are less clear.