Results of the expected observable velocity perturbations from a VSI unstable disk ¹²CO synthetic lines observations (v₀ − v_eq), for various velocity and spatial resolution data cubes. Each channel of the cube has a RMS noise expected from a 20 h integration ALMA observation with an extended configuration (1.9, 1.5, 1.0, 0.8, 0.6 mJy from the higher to the lower velocity resolution cases). In addition, we show the uncertainties in the calculation of the velocity centroid map using  BETTERMOMENTS (δv₀). The FWHM of the circular Gaussian beams are 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.