Half-life of radionuclides determined by the reference source method

Abstract

An approach for half-life determination using the reference source method associated with gamma-spectrometry with a Ge detector is presented. The method reduces the contribution of the type B component of the total uncertainty. The independence of the method regarding the instrumental interferences or radiochemical impurities was evidenced. However, there are some limitations when the method is applied for a genetically-related impurity with the same or very similar energy to that of the radionuclide to be measured, e.g., if 99Mo in a 99mTc sample is present. The measured half-life values are in good agreement with those of the literature and the associated uncertainties are lower than 0.1%.