Year
1998
Abstract
Response functions generated using an accurate physical model of CdZnTe detectors were used to assay 239Pu and to measure 241Pu/239Pu ratios for variable-burnup plutonium measured with a coplanar-grid detector. The analysis method involves fitting all known gamma-rays produced by the plutonium isotopes and 241Am in the region 330-to 700-keV region. This method is compared to the standard region-of-interest analysis technique used in nuclear material holdup measurements. Regional response function analyis is found to significantly improve assay accuracy and enables limited isotopic analysis.