Left panel: observed non-convolved profile of the atomic and molecular lines as a function of the distance to HD 200775 along the cut shown in Fig. 5 and described in Sect. 4. Middle panel: density profiles at two different maximum densities used by Köhler et al. (2014) in their analysis of the molecular emission. Model 1 has a peak gas density of 10⁵, model 2 a density of 10⁶ cm^-3. Right panel: observed profile emission of the [O i]145 μm line compared with the convolved predicted emission by Meudon PDR models.