Ideal ¹²C¹⁶O (3−2) velocity-channel map of a T Tauri disk model with an embedded Jupiter-mass planet with an orbital distance of 80 AU. The disk mass amounts to 2.67 × 10^-5 M_⊙, which is the lowest disk mass in our sample, and the outer radius is 144 AU. The flux density in Jy/mas² is color coded for each individual channel. The disk is seen face-on (0°). The gap is clearly visible, particularly in the line wings. Even more complex features like the huge spiral arm (e.g., at 300 m/s) can be recognized. The total width of the line is only given by thermal and microturbulent velocities (Sect. B.2).