Observing Carbon and Oxygen Carriers in Protoplanetary Disks at Mid-infrared Wavelengths

Infrared observations probe the warm gas in inner regions of planet-forming disks around young sun-like, T Tauri stars. In these systems, H$_2$O, OH, CO, CO$_2$, C$_2$H$_2$, and HCN have been widely observed. However, potentially abundant carbon carrier CH$_4$ remains largely unconstrained. The James Webb Space Telescope (JWST) will be able to characterize mid-infrared fluxes along with several other carriers oxygen. anticipation JWST mission, we model physical chemical structure a disk predict abundances observable molecules. A range compositional scenarios are explored involving destruction refractory materials alterations total elemental (volatile refractory) C/O ratio. Photon-driven chemistry surface layers destroys initial oxygen carriers. This causes models same ratio similar steady state compositions, regardless abundances. Initial compositions better preserved shielded midplane. degree similarity between midplane depend on characteristics vertical mixing at radii. Our modeled molecules respond sensitively changes temperature, radius, As result, useful probes fundamental parameters, including ratio, which can compared values determined for planetary atmospheres.