Radioisotope Discrimination Algorithm for Arms Control Inspections

The objective of this effort is to evaluate a proposed technique to discriminate a desired radioisotope of interest (e.g. Pu-239) from undesired radioisotopes (e.g. Pu-238) without collecting and storing a gamma radiation spectrum. In a possible future treaty verification regime, collecting a spectrum of a nuclear warhead would be problematic due to the classified nature of the spectrum. This technique could potentially be used in applications such as warhead confirmation, chain-of-custody, or dismantlement confirmation. To determine if the object being measured is consistent with a warhead or warhead component, the measured spectra is compared against undesirable radioisotopes that could be substituted. This is done by constructing an importance weighted matrix and binning each individual photon count in list mode. This rolling calculation ensures that a spectrum is never collected. The significance of this method is to allow easier certification of a template matching technique for use in an arms control treaty environment while still maintaining a reasonable false positive probability.