Modeling results and observations of the ¹³CO and C¹⁸O emission for the best-fitting models in derotated images and spectra. The left panels show the direct image comparison of the zero-moment map: derotated observations, model, convolved model, and residual. In the residual map the overlaid contours indicate the 3σ levels, where dashed lines are negative. The central panels show the gas density profiles with different δ_gas2 drops as solid lines and the dust density profile as dashed lines. The right panels show the resulting intensity cuts for the major and minor axis for both ¹³CO and C¹⁸O. The best-fitting model is indicated in red, other δ_gas2 values in blue. The drop in density can be constrained to within an order of magnitude.