Measurement of proton-induced prompt low energy photons by high resolution spectrometry

Abstract

Prompt photons with energies of between 20 and 200 keV are not often favoured for analytical use because the resolution of Ge(Li) detectors is insufficient to cope with the high density of photopeaks that occur in that energy region of the spectrum, and the efficiency of Si(Li) detectors is very low for photons with energies above about 30 keV. Using thin intrinsic germanium detectors, a survey was carried out of the photons emitted by 77 elements under proton bombardment, either in the pure form or as pure compounds. From the survey, those photons that were potentially useful for analysis were identified and their yields measured for proton bombarding energies from 3.5 to 6.0 MeV. Some subjects for intensive study were identified. Because of the known high yields of the 110- and 197-keV gamma-rays from fluorine, the determination of this element in cements is reported. Several transition metals could be determined through the spectrometry of their low-energy prompt gamma-rays. The simultaneous use of prompt K X-rays and low energy gamma-rays made it possible to determine some rare-earth elements. The same approach was used for the determination of alloy metals in a gold matrix.