Year
1982
Abstract
Reliable estimates of the precision and accuracy of nondestructive calorimetric assay have been made for a wide variety of plutonium-isotopic compositions and material forms. Material forms studied include oxides, metals, mixedoxides and intermediate-process categories. Isotopic compositions range from 6 to 22% plutonium-240. Quantities ranged from 0.2 to 2000 grams of plutonium. Estimates of accuracy and precision were based on comparison with traditional wet chemical assay techniques. Typically the precisions and accuracies were 0.5°/o or better. These error estimates are in good agreement with internal uncertainties propagated from the calorimeter precision and the counting statistics of the gamma-ray isotopic measurement. This study shows that these internal error estimates are reliable approximations of the total measurement error. The measurement techniques can thus be applied to a wide variety of materials without performing similar experiments on every material category in the process.