Figure 10.

Effects of spatial filtering for K_β fluorescence in abdominal prescan for 1.0 mg/mL gold in large intestine: (a) Detector panels selected (green) and deleted (red) for significance calculation after spatial filtering. Cylindrical detector area is spread flat, thus angular position of a tile is plotted against its position over long side of the detector. For K_β, mostly backward panels are used for significance calculation because of a smaller background from single Compton scattered photons there; (b) corresponding energy spectra before and after filtering. In green, contribution of all fluorescence photons to total spectrum is shown. After spatial filtering, K_β peaks are visible, whereas the background in K_α region is not decreased enough to make fluorescence photons detectable.