Overlay of the velocity-integrated CO (6–5) (colour background) with the CO (3–2) (white contours) emission observed with the APEX telescope. For both lines, the intensity was integrated between –30 and 40 km s^-1. The wedge unit is K km s^-1 in antenna temperature. The CO (3 − 2) contours are from 30 to 160 σ, in steps of 10σ = 16 K km s^-1. The half-maximum contours of the CO (3 − 2) and (6–5) maps are indicated in red and black, respectively. The dark blue circle indicates the position and beam size of the SOFIA/GREAT observations. The APEX beam sizes of our CO (3 − 2), (4–3), (6–5), and (7 − 6) observations are also provided (upper right corner light green circles, see also Table A.1). The maps are centred at (RA_[J2000] = , Dec_[J2000]  =  −23°19′25″). The black and light blue hexagons mark the position of the OH masers observed by Claussen et al. (1997) and Hoffman et al. (2005).