Single scattering albedo ω times the single scattering polarization degree P_ℓ at a scattering angle of 90° as a function of maximum grain size (top) and wavelength (bottom). In the top figure (a), the different line colors represent the four central wavelengths of the SOFIA/HAWC+ bands A, C, D, and E. The size distribution is described by Eq. (9) with an exponent of q = 3.5. In the bottom figure (b), the different line colors represent the case of different maximum grain sizes a_max and exponents q of the size distribution. The gray dashed vertical lines indicate the central wavelength of the SOFIA/HAWC+ bands A, C, D, and E. See Sect. 4.2 for details.