Integrated intensity (zeroth moment) maps for ¹³CO (first column) and C¹⁸O (third column) in the warm model with a constant CO abundance of 10⁻⁴ (top row) and 10⁻⁵ (bottom row). The emission is simulated with the observed uv-coverage (25 minutes integration). The intensity (color) scale is different for each panel. Second and fourth columns: residuals obtained by subtracting the models from the observations. Black contours are in steps of 3σ starting at 3σ, while orangecontours are in steps of − 3σ and start at − 3σ. For ¹³CO (C¹⁸O), 3σ corresponds to 25.9 (21.8) mJy beam⁻¹ km s⁻¹. The position of the continuum peak is marked by a cross and the beam is shown in the lower left corner of the moment zero maps.