Difference of the flow speed from the unperturbed Keplerian shear. The results were obtained from m01 − hw0 (panel a) and m05 − hw0 (panel b). The dashed blue, dashed-dotted white, and dotted white lines denote the fitting formula for the critical recycling streamline, the x-coordinate of the critical recycling streamline at the midplane in the far field, and the x-coordinate of the edge of the subsonic region, respectively. As in Fig. 3, we highlight the widest horseshoe streamline and the shear streamline passing closest to the planet with the solid and dashed orange lines, respectively.