Analytical formulae for well-type NaI (Tl) and HPGe detectors efficiency computation

A straightforward analytical formulae for the computation of total and full-energy peak efficiencies of NaI (Tl) and HPGe well-type detectors are deduced. In addition, the attenuation of photons by the source container and the detector end cap materials is presented in a direct mathematical expression. Results are compared with previous treatments.