252Cf: the potential for activation analysis of selected medium-weight and heavy elements in the limited neutron flux of a partially depleted 50 μg source

A 50 μg 252Cf source, depleted by about 2 orders of magnitude from its original neutron output, was used to examine the sensitivity of neutron activation analysis for a selection of 20 pure materials and compounds containing elements with atomic numbers greater than 40. Generally speaking, the sensitivity is seriously restricted by the neutron flux of the source, but in certain specific cases the nuclear properties of the elements concerned, such as thermal absorption cross-section, isotopic abundance and half-life of the radioactive product were considered for the production of a practicable gamma-ray yield. A description of the irradiation assembly and the conditions of activation are presented. Detection limits varied between 30 μg g−1 to 8.2 mg g−1 based on the most suitable gamma-ray of the radionuclide of interest. For purposes of determining trace and minor concentrations of selected elements, a source of this nature could be acquired at a nominal cost especially in developing countries that do not have access to a nuclear reactor.