LABOCA continuum image at 870 μm, with black contours placed at 25, 30, and 35 mJy beam⁻¹, as in Fig. 3. The white circle represents the beam size (beam FWHM = 22′′). Red contours correspond to the ALMA and APEX CO(2−1) combined line emission convolved to the APEX resolution of 22′′, integrated between 172 and 176 km s⁻¹, at 5σ, 6σ, and 7σ, where σ is the rms of the integrated image (σ = 1.8 Jy beam⁻¹ km s⁻¹). The scalebar in the lower right corner represents a 5 pc length.