Celestial emission model components for galactic 511 keV radiation. From top to bottom: galactic 511 keV line map as determined in Siegert et al. (2016) in linear scaling; same as shown in the top panel, but in logarithmic scaling to emphasise low surface-brightness regions; exemplary ROI region of Δl × Δb = 3.00° × 21.00° size, centred at l = 4.75°; complementary map, excluding the ROI region. The contours indicate regions in which 20, 50, 80, 98, and 99.7%, respectively, of the total flux is contained (from inside to outside).