Orthographic view of the polarization maps. First row shows the 353-GHz maps of the reduced Stokes parameters from Planck downgraded at N_side = 64 and the corresponding map of uncertainties that we use to compute the χ² (q, σ_q, u, σ_u). Rows 2–5: GMF models labeled ASS, LSA, BSS, and QSS using the best-fit of the ED n_d model. The obtained best fits are shown in the first and third columns and the statistical significance of their residuals, per-pixel, are shown in the second and fourth columns. The same convention is used as for Fig. C.1.