`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 ³He 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