Observations of the high-velocity clump. Upper panel: integrated line intensity (moment-zero) map of the CO v = 0,  J = 2 − 1 emission integrated in velocity between −14 and −1 km s⁻¹. The white ellipse in the lower right corner shows the size at half maximum of the ALMA gaussian beam. Lower panel: spectrum extracted towards the region defined by the blob in the upper panel (blue histogram). A gaussian fit to the emission associated with the blob is shown in the solid orange line. For reference, the vertical dashed grey line indicates one of the values for the systemic velocity derived by us (7.4 km s⁻¹).