Fig. 9. The 9.6 µm  feature (top) and 6.2 µm -AIB (bottom) both in contours superimposed to the S(1) line emission of molecular hydrogen taken from van der Werf et al.  (1996) (grey scale). The contours correspond to integrated band intensities from 0.02 to 0.11 by steps of 0.01 (top figure) and 0.045 to 0.27 by steps of 0.025 (bottom figure) in units of erg s^-1 cm^{- 2} sr^-1.