Source plane reconstruction split by spectral channels. Left panel: positions (colored thick dots) and shapes (ellipses) of the reconstructed profiles of the individual ¹²CO(9 − 8) channels, over-plotted on the map of the dust continuum emission in the source plane. The ellipses are plotted at 1/20th of the peak flux of each reconstructed channel map. Central panel: zeroth moment map of the ¹²CO(9 − 8) emission line derived from the reconstruction of the seven individual channels shown in the left panel. The contours show the dust continuum emission, starting at 1/20 of the peak flux in steps of 1/20th (see also Fig. A.3). Right panel: zeroth moment map obtained splitting the ¹²CO(9 − 8) in two halves, corresponding to the velocity ranges from −312 to 168 km s⁻¹ and from 168 to 528 km s⁻¹, and reconstructing them separately. In all panels, the cross at the lower right corner marks the phase center of the NOEMA observations.