Position–velocity map along the axis shown in Figure 7. The spectrum on each position is averaged along a 1° width line perpendicular to the axis. The grayscale background indicates ¹²CO, black contours indicate ¹³CO, and white contours indicate C ¹⁸O. The lowest contour is 10σ, and the contour interval is 10σ (0.28 K) for ¹³CO and 5σ (0.1 K) for C ¹⁸O. Projected positions of six regions are marked.