Line centroid (top), peak intensity (middle), and line width (bottom) residuals for the 1.0 M_Jup snapshot. The planet was removed and the gas velocity set to be fully Keplerian in order to analyse the contribution of the gas gap alone. The azimuthal scans on the left run along constant radii contours, whose colours represent their closeness to the gap, centred at R = 100 au. Although the velocities are Keplerian, the high (symmetric) centroid velocity residuals remain due to intensity differences between simulation and model at the location of the gap (see Fig. A.2). By simple comparison with Fig. 6, it is easy to identify the impact of the planet on the intensity and velocity residuals.