First moment maps of C¹⁸O 2–1 (top) and 6–5 (bottom) for the three simulations viewed i = 45° convolved with a 0.1″ beam. The solid line shows the 20% intensity contour of the moment zero () peak map to indicate the flattened structure. The black dashed lines indicate the direction at which the PV slices are constructed and the direction of the elongation in the zeroth moment maps.