Velocity map of ¹²CO. The figure shows the analytic spiral wake overlaid on top of the ¹²CO velocity map. The gray dot in each image indicates the position of the planet at the midplane. (left) Spiral wake for R_P = 100 au. The two curves show the spiral wake at the midplane (green solid line) and the CO top surface layer (dashed gray line). (right) spiral wake for R_P= 200 au. The two curves show the wake (projected on the CO top surface layer) for two different values of h_P.