PNNL

Abstract

The role of active-interrogation systems is to detect the presence of special nuclear material inside an object by observing the radiation emitted by that object when it has been exposed to known sources of external radiation. Because of the cost, complexity, and the need to avoid irradiating occupants, active-interrogation systems are intended for cargo applications where shielding can prevent detection by passive radiation detection systems. To ensure that active-interrogation systems are designed and tested to a consistent level of performance, technical capability standards are needed for evaluating active-interrogation systems. This paper addresses the testing standards needed for active-interrogation systems to detect high atomic number materials, fissionable materials, and specific special nuclear materials. The results given are based upon modeling scenarios constructed to evaluate options for surrogate materials that could be used for testing of such systems.