C¹⁸O J = 1 → 0 emission separated into blue and red components, using the line fitting and splitting by Duarte-Cabral et al. (2010). The blue emission corresponds to the total integrated intensity of the low-velocity cloud and the red emission corresponds to the high-velocity cloud. The submillimetre sources from the 850 μm emission (Davis et al. 1999) are marked with white triangles and serve as a guide to the location of the dust emission. The positions of the PV diagrams in Fig. 2 are shown by the white solid lines, and the main axis of the blue-shifted and red-shifted cloud is shown as blue and red dashed line, respectively.