Dust power spectra, D_ℓ = ℓ(ℓ + 1)C_ℓ/2π, at 353 GHz for TT (top), EE (middle), and TE (bottom). The power spectra are computed from a cross-correlation between the detset maps at 353 GHz for different sets of masks, as defined in Sect. 3.2.1, and further corrected for the CMB power spectrum (solid black line) and CIB power spectrum (dashed black line). The coloured dashed lines are simple fits, as described in the text.