The International Atomic Energy Agency is examining whether a new radiation sensor technology could aid in monitoring nuclear reactors for unreported plutonium and uranium possibly intended for military use, LiveScience reported on Friday (see GSN, Nov. 4, 2010).

Researchers at the Lawrence Livermore National Laboratory in California and the Sandia National Laboratories in New Mexico have conducted proof-of-principle trials of the technology, which measures neutrons and gamma rays produced by contact between antineutrinos, a type of antimatter particle generated by the nuclear fission process.

Equipment employing the technology might be deployed dozens of yards from a reactor core. Installation of an antineutrino detector below the Earth’s surface would maximize the device’s accuracy by shielding it against interference from outer space, but scientists are working on mechanisms to account for irrelevant signals picked up by surface-level equipment.

The completed proof-of-principle tests involved a liquid scintillator detector interred roughly 10 yards underground. Testing is now under way of two experimental surface-level devices, one a solid-plastic scintillator and the other a water-reliant scanner.

“If this technology was to be accepted broadly, I’d expect an antineutrino detector to cost $100,000, comparable to other reactor safeguard systems in use, with greater capability,” said Nathaniel Bowden, a physicist with the Lawrence Livermore National Laboratory.

“We have encouraging indications that we may have above-ground capability in the future,” he said (Charles Choi, LiveScience, April 15).