A development for determining the activity of radionuclides in the environmental sample by HPGe γ-spectroscopy using only one absolute efficiency value and an intrinsic efficiency

In the present work, we presented a development for determining the radio-activities in the environmental sample based on knowing only absolute (full-energy peak) efficiency value at the energy of 1460.83 keV corresponding to characteristic γ-ray of ⁴⁰K by using a reference in separate and an intrinsic (relative) efficiency function. The prerequisite for using this method is the presence of a multi-gamma-ray emitter in the sample, with an activity allowing to measure the count rates with the statistic uncertainty of few percents. Two standard samples were used to validate the development. Gamma-rays from ²²⁸Th or ²²⁶Ra decay series were chosen to construct the intrinsic efficiency functions. The results obtained were in good agreement with reference data. (author)