Radiative transfer solutions, obtained as described in Sect. 6.1, for τ(2–1) (left panel) and T_ex (second panel) of the ¹³CO emission data cubes. Third panel: resulting column density N(¹³CO), derived from the optical depth and excitation temperature cubes. The data in each panel have been integrated over the 1-degree extent in latitude, including any zero-valued pixels, to form the respective longitude-velocity moment maps shown here. Right panel: shows a similar lv moment map of the ¹³CO(2−1) emission as seen in the SEDIGISM data convolved to the ThrUMMS resolution.