Left: comparison between the H₂O 1₁₁ − 0₀₀ emission at 1113 GHz (19′′ beam size) at the R2 shock position (black), corresponding to the compact gas component, and that at the offset position (10′′, −10′′) with respect to R2 (red), corresponding to the extended component. The residual spectrum, given by the difference between the two displayed spectra, is shown in blue. Offsets are with respect to R2. The vertical dashed line indicates the source velocity. Right: same as the left panel for the CO (3−2) emission.