Fig. 5

The energy spectra obtained from the simulations of the phantom scanned in configuration B (HS + CB). The counts recorded in the photopeak window and correspond to the ROI drawn on the projection images: around the hot object (column b), in the background surrounding this ROI (column c), and in the entire image (column d). Column a shows the simulated PW projections. The hot object ROI was placed inside the red circle while the background ROI comprised all counts found on the outside of the red circle