CH⁺ steady-state normalized excitation diagrams computed with MADEX assuming n_H = 10⁴ cm^-3, T_K = 50 K, χ_opt = 10⁵, and N(CH⁺) = 10¹³    cm^-2. The number of vibrational levels taken into account within the X¹Σ⁺ and A¹Π electronic states varies between one (blue squares) and five (red pentagons). We also display for comparison the predictions of MADEX if the radiative pumping processes are switched off (black crosses).