Radial profiles of the NPS X-ray emission. Left: Observed surface brightness in several energy bands. The wedge used for the flux extraction is shown in Fig. 1. The bright edge of the NPS is at x ≈ 48°. The contributions of the instrumental background and distant (unresolved) sources composing cosmic X-ray background (CXB) have been subtracted, leaving only the flux from the Galaxy. Right: Same as the left plot, but after subtracting the mean level at x = 60 − 70°, re-normalizing by the flux at x = 35°, and lightly smoothing with a Gaussian filter (σ = 0.4°). In addition, the radio surface brightness profile (Haslam, 408 MHz) after applying the same procedure (subtraction, re-normalization, and smoothing) is shown with the dashed red curve.