Protoplanetary migration in non-isothermal disks with turbulence driven by stochastic forcing

Low-mass objects embedded in isothermal protoplanetary disks are known to suffer rapid inward Type I migration. In non-isothermal disks, recent work has shown that a negative entropy gradient can lead to a strong positive corotation torque which can slow down or reverse Type I migration in laminar viscous disk models. We examine the impact of turbulence on the torque experienced by a protoplanet embedded in a non-isothermal protoplanetary disk. We performed 2D numerical simulations using a grid-based hydrodynamical code in which turbulence is modelled as stochastic forcing. We find that the running timeaveraged torque experienced by a protoplanet embedded in a non-isothermal turbulent disk is in good agreement with laminar disk models with appropriate values for the thermal and viscous diffusion coefficients. In disks with turbulence driven by stochastic forcing, the corotation torque therefore behaves as in laminar viscous disks and can be responsible for significantly slowing down or reversing Type I migration.