The background-subtracted data (red crosses) of the 3–6 arcmin annulus are shown with the thermal model prediction extrapolated from the 2–7 keV band (solid black line) in the upper panels. The data are binned using a minimum of 2000 counts per bin for clarity. The ratio of the data and the extrapolated model is shown with black crosses in the lower panels. The error bars include the effect of the statistical uncertainties on the hard band model. The dotted blue line shows the results of using NH from Dickey & Lockman (1990). The results are shown for XIS1 (left panel) and XMM-Newton PN (right panel).