A compton scattering spectrometer for determining X-ray photon energy spectra

Abstract

The importance of knowing energy spectra of the primary photons from clinical X-ray tubes under working conditions increases with the use of more sophisticated diagnostic technologies. At the high fluence rates of primary photons from diagnostic X-ray tubes it is nessesary to strongly reduce the number of photons to the detector per unit time in order to avoid pulse pileup. The compton scattering method is very suitable for this reduction. This method, applied in the diagnostic energy range by Yaffe et al. [1] is further developed in this work. The electrons moving in the target cause an energy broadening (Compton broadening) of the scattered photons. This broadening smears out the characteristic peaks of the anode material and results in a decreased energy resolution. Comparison of the spectrum obtained with the Compton spectrometer, and unfolded with our reconstruction, to the spectrum measured directly in the primary beam shows a very good agreement, although relatively simple reconstruction algorithms are used.