Example of a progression of disk models taken from the grid to illustrate the effect of the change of parameters in the line-profiles and rotational diagrams. The observed data are plotted in black, and the model predictions in red. Error bars on the line-profiles are 3σ. The dashed line is the dust surface density from Matter et al. (2016). The model starts with a continuous gas disk that follows the same power-law as the dust in the outer disk, and it is refined until the best description of the CO ro-vibrational observations is reached. The two branches seen in the rotational diagram correspond to the R and P branches of CO ro-vibrational emission.