Template Applications for Monitoring Warhead Dismantlement

As further reductions in nuclear weapon stockpiles are planned, it becomes increasingly important to confirm with high confidence that items presented for monitoring and subsequent dismantlement are genuine nuclear weapons. The monitoring approach must make use of sufficient data to provide high assurance of authenticity but must do so without revealing sensitive design information to the monitoring party. Use of an open, secure processor to evaluate measured data and present only the non-sensitive results of the evaluation to the monitoring side is becoming an accepted concept. Technical options for monitoring weapon authenticity presently under discussion are being described as either attribute or template approaches. The fundamental elements of each type of approach are analyzed, misconceptions associated with the definitions are clarified, and complementary aspects are identified. A template is an experimentally determined pattern of characteristics whose measured values describe an item to be monitored. A template approach compares measurements of an unknown object with a template of reference data and reports only the variability of the match. Characteristics of nuclear weapons which might otherwise be unusable because of their sensitivity can be practically incorporated in template approaches. Use in the monitoring process of the quantitative variability parameters resulting from template comparisons is suggested as a means to resolve results that are intermediate between pass and fail. This work explores how increased assurance of weapon/component authenticity might be obtained, with minimal risk to sensitive information, by incorporating expanded classes of weapon characteristics into monitoring procedures, by using data of higher resolution or unrestricted accuracy, and by using variability information to trigger follow-up activities for resolution of anomalous or ambiguous situations.