Taking account of the interfering effect of a competing reaction in neutron-activation analysis

In activation analysis, there are cases where a radionuclide is formed from the elements being determined and from interfering elements [1]. For example, such cases occur in activation analysis performed using fast neutrons with energy14 MeV, since many radionuclides are formed in the reactions (n, p), (n, 2n), and (n, ) and sometimes in the radiative capture reaction (n, ) on different isotopes of the elements [2]. In the present work, we propose a method, based on the concept of isotopic ratio, for determining the fraction of the activity of a radionuclide formed from an interfering element in the total activity of the analytical radionuclide. It is assumed that at least two reactions occur on the interfering element with formation of the analytical and another radionuclide. The method is checked on the example of simultaneous determination of phosphorus and silicon by activation analysis with fast neutrons.