Upper panels: velocity-integrated intensity maps of the ¹²CO(2 →1) and ¹² CO(5 →4) line. We integrated emission within the velocity range of ± 750 km s⁻¹, i.e. about 8 channels, where significant line emission was detected. The contour levels of the ¹² CO(2 →1) line emissionmap are at [−2, 2, 3, 4] × 1σ, with σ = 0.05 mJy beam⁻¹ per 200 km s⁻¹ wide channel. Negative contours are shown in white and positive contours in blue. The beam size of 1.70 × 1.24 arcsec is plotted in the bottom left corner. The blue cross denotes the peak position of the [CII] 158 μm emission line. In the right panel we show the velocity-integrated intensity map of the ¹² CO(5 →4) line emission. Contour levels are at [−3, 3, 4, 5, 6] × 1σ, with σ = 0.13 mJy beam⁻¹ per 200 km s⁻¹ wide channel. The beam size of 5.0 × 2.6 arcsec is alsoplotted in the bottom left corner. Lower panels: ¹²CO(2 →1) and ¹² CO(5 →4) line spectra binned to 200 km s⁻¹ channels. The red solid lines are Gaussian fits to the line spectra, the central position is shown by the red dashed lines. The blue error bar denotes the typical 1σ rms value.