Abstract
In this paper a simple, rapid and general method for γ-ray efficiency calibration of Ge detectors for environmental samples is presented. This method is based on the use of an active natural solid sample with several γ-emissions (in our case, 226Ra) as the calibrating matrix for determining the full energy peak efficiency (FEPE) εc vs γ-emission energy Eγ and the sample height h in a counting cylindrical geometry. The 226Ra activity concentration is determined by α-particle spectrometry, a method that has previously been validated.