Year
1981
Abstract
RACT By combining the measurements obtained by calorimetry and gamma-ray spectroscopy, calorimetric assay provides a nondestructive method for determining the plutonium content of a sample. Simultaneous calorimetric assay refers to a system in which both of these measurements are performed at the same time. This paper reports the results of gamma-ray measurements performed in developing the Simultaneous Calorimetric Assay System. The transmission of gamma rays through the calorimeter was measured over the energy region germane to a determination of plutonium isotopic composition. For six different samples, a gamma-ray measurement of isotopic composition was obtained with the sample in the calorimeter. The items represented a range of plutonium content (19-231 g) and isotopic composition. The effective specific power was calculated from the isotopic composition determined by gamma-ray measurements. The uncertainty in the effective specific power indicates, for the items measured in this study and as measured in this study, the uncertainty in the total plutonium content of the sample expected in simultaneous calorimetric assay.