Non-LTE LVG fitting results for methanol (CH₃OH) with (full color) and without (shaded) considering the contribution from millimeter foreground dust absorption (see Sect. 3.2). Left: χ² minimization for the total column density ${\text{N}}_{{\text{CH}}_3\text{OH}}$ (A-type plus E-type). Middle: density–temperature χ² contour plots showing 1σ confidence level, assuming the best-fit value of ${\text{N}}_{{\text{CH}}_3\text{OH}}$ = 2 × 10¹⁸ cm⁻² and a source size of 0.″3. The best-fit solutions are marked by stars. Right: observed line integrated intensities vs modeled ones as a function of the upper-state energy level value with respect to the lowest value.