Experimental Study of the Photon Energy Spectrum of Primary Diagnostic X-Rays

Abstract

The photon energy spectra of primary diagnostic X-ray beams have been studied experimentally over the kilovoltage region 45-105 kvp using scintillation spectroscopy techniques. A method was devised which allowed the photon beam to be collimated without perturbing it and which permitted close reproduction of measurements. Correction for spectrometer distortion of spectra was done by means of a digital computer. Results are presented in terms of photon fluence per energy interval versus photon energy. Mean energies and half-value-layers were computed from the spectra. The half-value-layers were compared with independent experimental determinations using ionization chambers with essentially energy-independent responses over the photon-energy region of interest.