Year
1999
Abstract
Two complimentary candidate measurement technlogies were recently used to demonstate how excess plutonium with classified characteristics could be inspected for inclusion in a monitoring regime without revealing classified information. Two sensitive attributes, the ratio of 240PU to 239PU and plutonium mass, were measured behind a prototype \"information barrier\" that revented thier disclosure. A compasison was made behind the information barrier of the values of these sensitive attributes with unclassified thresholds. This compasison yielded unclassified pass/fail indications for the attributes that were displayed outside the informatio barrier. In this paper, we discuss special considerations associated with radiation measurements of classified items and specifics of te measurement technologies used in the recent demonstration-high resolution gamma-ray spectrometry and neutron multiplicity counting. Detailed considerations of information barriers and the information barrier demonstration are being addressed in other papers.