A test of high-energy electron bremsstrahlung calculations

Abstract

The dependence on atomic number Z of commonly used formulae for calculating electron bremsstrahlung spectra is tested by making measurements of d(γ,p)n cross-sections using aluminum and tungsten radiators for 165 MeV incident electrons. The ratio of the photon yield produced in the tungsten radiator to that produced in the aluminum radiator is determined, with an overall experimental uncertainty of about 10% per 5 MeV , as a function of photon energy in the range 70<E γ <150 MeV , and compared with the ratio obtained from theory. Good agreement with theory is found for photon energies between 90 and 120 MeV . Outside this range, the theoretical ratio underestimates the measurement by about 5% for lower and 15% for higher photon energies.