Emission of CO isotopologues and other bright molecular transitions. Channel maps consist of velocity ranges of 1 km s⁻¹ and moment 0 maps are integrated over a velocity range of 8 km s⁻¹. The contours start at 5σ and follow a step of 5σ for ¹³ CO, C¹⁸ O, and CS (the remaining follow a step of 3σ). The two white crosses in the CS moment 0 map indicate the position from which the spectra from Figs. 4and 5 are extracted. The yellow stars show the position of the sources and the solid segment represents the extent of the circumbinary disc. The synthesised beam is represented by a solid black ellipse in the right panels.