On-site inspection for the radionuclide observables of an underground nuclear explosion

Under the Comprehensive Nuclear-Test-Ban Treaty an on-site inspection (OSI) may be undertaken to identify signatures from a potential nuclear explosion. This includes the measurement of 17 particulate radionuclides (Zr-95, Nb-95, Mo-99, Tc-99m, Ru-103, Rh-106, Te-132, I-131, I-132, Cs-134, Cs-137, Ba-140, La-140, Ce-141, Ce-144, Pr-144, Nd-147). This research provides an assessment of the potential to detect these radionuclides during an OSI within 1 week to 2 years after a nuclear explosion at two locations. A model has been developed that simulates the underground detonation of a 1 kT U-235 nuclear weapon with 1 % venting. This indicates a requirement to minimise the time since detonation with accurate determination of the test location.