Dec 16, 2013
Science Lunch Talk: Ruobing Dong "Examining the Earliest Stage of Planet Formation through Disk-Planet Interactions in Protoplanetary Disks"
Title: Examining the Earliest Stage of Planet Formation through Disk-Planet Interactions in Protoplanetary Disks Abstract: Signposts of planets in protoplanetary disks produced by disk-planet interactions may provide us a unique way to probe and study the earliest stages of planet formation. In the first part of the talk, I will introduce the concept of disk-planet interactions, then present some numerical simulations of them in protoplanetary disks. Particularly, I will show gap opening in low viscosity disks by low mass planets due to the damping of the waves caused by the wave nonlinearity. In the second part, I will move on to observations of transitional disks, which are protoplanetary disks with central depleted regions (cavities), possibly cleared out by the forming planets. Recently, Subaru directly imaged a number of such disks at near infrared (NIR) wavelengths (the SEEDS project) with high spatial resolution and small inner working angles. Using radiative transfer simulations, we study the structure of these objects by modeling observations at different bands simultaneously. The complexity of transitional disks is reviewed by the variety of features captured in their observations, such as cavities, spiral arms, and other non-smooth/asymmetric structures in the disks, which indicate different underlying disk structure, possibly implying different origins of these objects.