Longitudinal profile of the X-ray, and SMD models data. Average count rate per pixel for the Fe XXV Band over Galactic longitude (ℓ), extracted from a profile of 0.5 deg width, centred at Sgr A^*. The XMM-Newton data are shown with black dots while the profiles extracted from the SMD Models 1 and 2 are shown with the blue and cyan dashed lines respectively. The red and blue points are XMM-Newton observations that include the SNR W28 and the dust scattering halos from bright XRBs, respectively, and therefore show an excess compared to the scaled Model 2.