Streamlines of gas (left) and trajectories of dust particles with St = 10⁻² (right) at the midplane of the disk. The flow structure around a planet is obtained from m03-hw001. With this parameter set, the planet-induced gas flow is in the flow-shear regime (see Sect. 3.2). The color contour represents the flow speed in the x direction, v_x,gas. We set z_s = 0 for the orbital calculations. The dotted and dashed circles are the Bondi and Hill radii of the planet, respectively. The thick blue lines in the right panel correspond to the trajectories of the dust particles that satisfy x′_s ≥ x_s (see Fig. 1 and Sect. 3.3 for details). The 3D structure of the gas flow field is shown in Appendix E.