Results of the expected observable velocity perturbations from ¹²CO synthetic lines observations, in which one of the velocity components is from a VSI unstable disk. The input VSI-active velocity field into the radiative transfer is modified to follow an equilibrium disk solution in two of the components. From left toright, the columns: predictions considering the contributions of the radial velocity, the meridional velocity and azimuthal velocity, respectively. From top to bottom: different rows show the results for disk inclinations of 5°, 20° and 35°. The mock data cubes have a velocity resolution of 0.05 km s⁻¹, and the images are convolved by a circular Gaussian beam of 50 mas, shown at the bottom left corner of each panel. The x- and y-axes indicate the RA and Dec angular offset from the position of the central star, in arcseconds.