(a) East and west sector regions used to extract the X-ray SBPs, which are shown in (b). Here, the Chandra ACIS image is used as the background image. (b) Chandra ACIS and XMM–Newton EPIC 0.3–2.0 keV SBPs extracted from the partial elliptical annuli defined in the two sector regions. For SBPs extracted in the east sector, a single β model can give an acceptable fit to the observed SBPs (dashed lines; Section 3.1 and Table 1). For SBPs extracted in the west sector, dashed, dotted and solid lines are used to show the best fits obtained with the single β model (Section 3.1), two-β model and truncated power-law +β model (Section 3.3 and Table 1), respectively.