Determination of 54Mn and 59Fe Specific Activities in Iron Plates Activation Detectors

Abstract

In reactor dosimetry it is well known that the empirical determination of the neutron flux is performed by determining the isotope 54Mn generated in a (n, γ) nuclear reaction. This study presents a procedure for the simultaneous determination of the radioisotopes 54Mn and 59Fe, developed to obtain more complete information about the process. The basis of the method is the irradiation of iron-plate detectors with a neutron flux generated in a VVER-type nuclear reactor and subsequent gamma spectrometric analysis of the samples to determine the two radionuclides obtained in two simultaneous (n,x) and (n, γ) nuclear reactions. A very important stage of the assay is the preliminary radiochemical treatment of the samples involving the removal of oxides and corrosion products and the dissolution of the plates in strong mineral acids. The results show that our approach of simultaneous determination of 54Mn and 59Fe significantly improves the time of analyses, reduces the radiation dose, and increases the accuracy and efficiency of neutron fluence determination. The procedures are relatively easy to perform and are suitable for application in routine studies.