This paper examines the potential role of thermal neutron analysis (TNA) in unexploded ordnance (UXO) and mine detection. The results of two different field tests for two different TNA systems are presented. The two tests differed greatly in intent and scope: one test focused on the application of TNA to UXO remediation, where the targets of interest ranged from 105-mm projectiles containing about 610 g of nitrogen down to 20-mm rounds containing less than 5 g of nitrogen; the second test focused on the application of TNA to antitank landmine detection, where the targets ranged in size from 1 to 3 kg. The first test clearly demonstrated a proof-of-concept, but the performance fell short of the values needed to make the system operationally useful. Hardware upgrades are suggested to improve performance, with an emphasis on HPGe detectors to eliminate the problems introduced by the Si29 background. The performance of the second TNA system in the second test also fell short of what would be desired in an operational system, although all results from that test have an uncertainty associated with them because of the small sample size involved. The hardware upgrades discussed for the first system would also be applicable to the second system.
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