Integrated intensity of the blue ([–5, 5] km s^-1), central ([5,12] km s^-1), and red ([12, 20] km s^-1) intervals of the CH⁺ 1−0 (color scale) and [C ii] lines (black contours, starting at 15 K km s^-1 with a step of 5 K km s^-1 for the blue interval, starting at 50 K km s^-1 with a step of 50 K km s^-1 for the central and red intervals). White contours are the integrated intensity between 5 and 15 km s^-1 of the C¹⁸O 2−1 line. In the blue interval, the CH⁺ absorption (dark color) correlates with the molecular cloud.