SAIC Detects Illicit Nuclear Materials Through Innovative Product

Detecting illicit nuclear materials is a vital part of preventing nuclear proliferation and nuclear terrorism around the world. The job has become more difficult because of the scarcity of the central element in detection devices, Helium-3 (He-3), a rare-in-nature Helium isotope. SAIC has responded with a solution.

Historically, He-3 has been used in devices that detect the emission of neutrons, the tell-tale signature of plutonium, uranium and other special nuclear materials. Many kinds of radiation detectors can be used for nuclear weapons detection, including those detecting gamma rays. But neutrons are unique to nuclear weapons material as they indicate a presence of fissionable radioactive substances.

He-3 is only readily available, however, as a by-product in the production of nuclear weapons. Nuclear weapons production has decreased, and with it, the supply of He-3. At the same time, the demand for He-3 is on the rise - not only for detection devices, but also for medical applications and nuclear physics experiments. SAIC's science-based answer provides a drop-in replacement for He-3 detectors in radiation portal monitors that guard against nuclear smuggling.

SAIC physicists came up with NeuSand™ (short for neutron sandwich). SAIC did the development internally, and holds two patents for the unique design of the technology.

NeuSand detects the presence of neutrons by generating light, according to SAIC physicist Raulf Polichar. NeuSand has thin layers of Lithium-6 and a highly efficient scintillator, a material made of zinc sulfide that re-emits energy in the form of light. The screen and scintillator are then "sandwiched" between layers of transparent acrylic. When positioned near nuclear materials, the neutrons emitted from those materials are slowed down by the hydrogen in the acrylic and then absorbed by the Lithium-6, which breaks up into an alpha particle and a tritium particle that together give off over 4 million electron volts (4 MeV) of energy. This energy is absorbed by the scintillator and re-emitted as light.

This technology as applied by SAIC results in a flexible, readily integrated replacement for He-3 detectors in radiation portal monitors. It is a cost-effective, low-power, low-complexity, robust solution that has no gas, no fragile tubes and no toxic materials.

"We're frankly proud that SAIC had both the foresight and the capability to put together what we believe is an elegant solution to a pressing national, and global problem - the efficient, effective detection of illicit nuclear materials," said John Fratamico, business unit general manager.

In addition to radiation portal monitors, SAIC is working on adapting the technology for potential use in nuclear-powered vessels in radiation safety applications.