CS .J = 2−1 emission at 97.98 GHz towards IRAS 15194–5115, in a 3.3 km s⁻¹ wide channel centred on the systemic velocity. Left: archival data. Right: reprocessed data. The emission shown has been capped at 50 mlybeam⁻¹ to make the low-level extended artefacts clearly visible. The white contours are at 5 mly beam⁻¹. Synthesised beams are shown as filled black ellipses in the bottom left corner of each panel.