A Neutron Sensor for Detection of Nuclear Materials in Transport

Spent fuel from nuclear reactors, even weapons‐grade plutonium, and certain weapons‐initiator materials emit large numbers of neutrons from spontaneous fission or (alpha, n) reactions. These are materials which terrorist groups could fairly easily obtain for construction of radiation dispersion weapons or fission weapons. Because the U.S. borders are fairly easily crossed in many wilderness areas and because these materials could be obtained from sites within the U.S., it is not sufficient to inspect baggage and cargo at points of entry. Very sensitive neutron detectors coupled with surveillance cameras could be positioned at highway choke points on the outskirts of major cities or near other sensitive locations to detect neutrons from contraband nuclear components and provide warnings to security personnel to try to prevent such an attack. The major advantage of neutron detectors over beta and gamma detectors is that the background rates and incidences of false positives would be much lower. There is onl...