Gamma-Spectrometric Control of Fissile Mass and Distribution Uniformity in Fuel Pins with Uranium-Plutonium Nitride Fuel

Abstract

A non-destructive gamma-spectrometric method of determining the characteristics of fissile materials in fuel pins with uranium-plutonium fuel is presented. The measurements were performed with the aid of a scanning apparatus with an ultrapure germanium detector. The uniformity of the mass and plutonium distributions was monitored according to the counting rate of the pulses in the 413.7 keV peak of ²³⁹Pu. The FRAM code was used to determine the isotopic composition of plutonium in a fuel pin. Multiple repeated measurements were performed and the repeatability and reproducibility of the determinations of the characteristics of the fissile materials in a fuel element were determined.