'Neutron signatures' (weapons treaty verification)

The Radiation Detection Section of the Naval Research Laboratory (NRL) is sponsored by the Defense Nuclear Agency (DNA) to study the feasibility of using passive cosmic-ray induced neutron signatures as a method of treaty verification. The main thrust has been to use the neutron signature as a unique method for verification of the type of missile or other treaty limited item (TLI) inside a closed container. The detector for the experiments described consisted of nine /sup 3/He neutron proportional counter tubes that were three feet long and at a pressure of ten atmospheres. The object of the experiments was to use this neutron detector to measure the neutron signature of a semi-realistic mock-up of a generic missile. Clear variations in the neutron signal at different points over the mock-up are shown, demonstrating that measurable neutron signatures do exist.< >