Density (top) and numerical viscosity equivalent α value (bottom) time-averaged over 10 orbital periods (t∕t_*∈ [90, 100]) with a sampling rate of 0.1 orbital periods. The solid blue shadows indicate the variation interval over the sample time series, showing that the profile is very stable in the region of interest. The hatched regions highlight the wave-killing zones, while the orange region loosely indicates the vortex-forming region, spanning one scale height away from the local density maximum.