Imaginary part (k) of the refractive index for the aerosols. Jupiter analog experiment (Khare et al. 1987) is shown in black, the tholin experiment (Khare et al. 1984) reduced by a factor of five is shown in blue, the Titan Cassini-CIRS observations (Vinatier et al. 2012) are shown in orange and the Saturn Cassini-CIRS observations (Guerlet et al. 2015) are shown in red. The gray regions mark the spectral region where the aerosols were analyzed in this work.