Comparison between measurement and Monte Carlo simulation of a bremsstrahlung source

Abstract

10 MeV electrons delivered by the 15 MeV linear electron accelerator of the University of Ghent are used to irradiate a tantalum/graphite bremsstrahlung source. Since earlier work showed that the theory given by Monte Carlo simulations of the source using the codes EPCOT and EGS4 overpredict the spectrum's intensity at low energy, a new direct measurement of the bremsstrahlung source was conducted with a germanium detector at different angles. Another germanium detector was used which improved the quality of the gamma-ray spectrum and similar but better experimental set-up geometries were constructed. In order to make a clear comparison between simulations and direct measurements, the Monte Carlo calculations included not only precise simulations of the sources but also of the germanium detector response. All these improvements were done to understand the disagreement between the Monte Carlo simulations and the first measurement.