Hydrodynamics of the Irradiation Instability

For most of a protoplanetary disk, stellar illumination is the dominant heat source that provides pressure support. Pressure shapes the disk’s vertical structure, which in turn determines the amount of heating the disk receives. However, most disk models do not treat this process self-consistently. Recent works have attempted to bridge this gap using simplified models. These suggest that temperature fluctuations in the disk may grow into order-unity thermal waves that significantly impact its evolution. Here, for the first time, we use a modified version of Athena++ to capture, simultaneously, the stellar illumination and the disk’s hydrodynamical responses. In this talk I will describe our implementation and share a number of surprising behaviours from our early results.