Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English   Periodicity: 4 times per year   Open access peer reviewed journal

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A. N. Berlizov, V. V. Tryshyn

Abstract: Statistical characteristics of multi-group analysis technique for isotopic composition determination of uranium samples, realised in the form of portable "U-Pu InSpector" spectrometry system and MGAU V.1.0 code, have been studied with the help of uranium isotopic standard reference materials in the range 0.32 - 4.5 % of ²³⁵U and 0.004 - 0.036 % of ²³⁴U concentration. The influence of a number of factors that can cause systematic bias of measured values are also studied. Obtained results reveal dependence of measured ²³⁵U enrichment level upon isotopic composition of uranium sample and geometry of the measurement. Systematic underestimation of measured ²³⁴U content turned out to be of about 23 % in the concentration range. Possible sources of revealed systematic biases are discussed as well as some recommendations for improving of MGAU code are given.

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