Top-ranked models from our residual minimisation and considered good fits upon inspection of the line profiles. Observed spectra of the CO v = 0,  J = 2 − 1 line extracted from five different aperture sizes is shown by the blue histogram. From left to right, the apertures diameters are 45 mas, 90 mas, 135 mas, 180 mas, and 240 mas. The dashed yellow lines represent the models. The first row shows our best model from Section 6.2, while models from the grid considered acceptable are shown in the following rows.