“Mouri diagram”. The data regions correspond to shocks (Brand et al. 1989), non-thermal (Black & van Dishoeck 1987) and thermal UV (Sternberg & Dalgarno 1989), and X-ray (Lepp & McCray 1983; Draine & Woods 1990). The diamond corresponds to data extracted from our whole FoV, the triangle to data extracted from the bright H₂ knot in the east, and stars to data from other galaxies (NGC 1275 and NGC 6240 taken from Krabbe et al. 2000). The red arrow shows the displacement for a reddening correction of A_K = 1.