Rotational diagram for CH₃OCH₃, ν= 0, uncorrected for the predicted optical depth (left) and corrected for the optical depth (right), in all other aspects the data is treated in the same way, as well as that the same symbols and line-styles are used in both panels. Line-emission from other species, derived from an isothermal model of all identified species minus dimethyl ether, has been subtracted from the dimethyl ether emission in both figures. The filled squares (■) indicate the lines with E_u > 200 K and open squares (Λ) lines with E_u < 200 K, detected with SHeFI in the 230, 290 and 345 GHz windows. The open triangles (△) indicate CHAMP⁺ data. The solid line shows the least squares-fit to the E_u > 200 K data and the dotted line the least-square fit to the E_u < 200 K transitions. The dust absorption has been corrected for. N_T for the fit to the transitions with E_u > 200 K is 5.5 × 10¹⁷ cm^-2 and T_rot is 105 K for a source size of 2.6′′. For the transitions with E_u < 200 K these values are 5.0 × 10¹⁷ cm^-2 and 82 K, respectively for a source size of 3.2′′.