Panels a−d: observed on-axis line profiles (histograms) and transverse PV diagrams (color map and white contours) of SO₂ (left) and SO (middle) at ± 70 au across the northern blue jet (top) and the southern red jet (bottom). The red wing of SO falls outside our spectral set-up. A DW model fit, with λ = 5.5 and (see text), is overplotted in black for parameters denoted in each panel. Panels e−f: PV diagrams observed by Lee et al. (2017a) across the SiO knots N2 and S3 (grayscale and black/red contours). Their measured centroids are shown as green squares and fitted rotation gradient as a black line. The DW model is overplotted in cyan (top) or magenta (bottom) with parameters denoted above each panel.