Oral Presentation

Volatile Chemistry of Protoplanetary Disks

Author(s): Fujun Du (Purple Mountain Observatory)

Presenter: Fujun Du (Purple Mountain Observatory)

It has been found that some carbon- and oxygen-bearing species are depleted relative to dust in some protoplanetary disks, e.g. in TW Hya and DM Tau, while hydrocarbon molecules such as C2H and C3H2 in the same disks exhibit prominent ring structures. To understand these facts, we propose that oxygen is depleted relative to carbon in the outer part of the disk, caused by the formation of ice-covered grains followed by the sedimentation and aggregation processes. We modeled this effect in a parametric approach, which is able to reproduce the observational results. The indication is that dust evolution is tightly coupled with gas phase chemistry. Future work needs to find more connections between dust and gas phase chemistry, e.g., how are ring structures in different species (including dust) related? How are different elements circulated in the disk, in tandem with dust particles? How does these processes affect the composition of the forming planets? Data from different telescopes including Subaru will be important in answering these questions.