Streamline model of the CS blue-shifted emission for the set of parameters (r₀, θ₀, φ₀, v_r,0) = (1500 au, 115°, −160°, 1.4 km s⁻¹) around the axis. See Sect. 4.2.1 for more details. Left: theoretical projected trajectory (in pink) from the streamline model overlayed on the CS blue-shifted emission and the two brightest peaks of the SO emission of Fig. 7. The contour levels are 65σ to 125σ by 10σ steps where σ = 1.0 mJy beam⁻¹ km s⁻¹. Right: theoretical line of sight velocity profile from the streamline model overlayed on the KDE of the C₂H blue-shifted velocity map. The vertical dotted line corresponds to the disk v_LSR = 7.37 km s⁻¹, the horizontal to the 0″ offset.