More than two billion tons of cargo pass through ports and waterways in the United States every year. Many of these ports rely on cobalt-60 scanners for cargo screening. Because of the radioactive nature of cobalt-60, the industry is leaning toward the use of high-energy X-rays generated by particle accelerators. Improved accelerator and detector technology could be used to detect threats, such as special nuclear material (SNM) or weapons in ship-borne cargo containers and at stand-off distances before the materials enter U.S. ports.
Electron beam accelerators produce higher energy X-rays, which can penetrate deeper than existing systems and provide more information about the nature of the cargo. High-intensity X-rays are imperative for active interrogation methods for SNMs such as photo-fission, delayed neutron and gamma measurements, pulse-shaped discrimination and nuclear resonance fluorescence.
At present, electron beam accelerators reside in a fixed location. Development of new technology at Fermilab allows for the construction of efficient, compact, high-power, high-energy accelerators that enables increased and portable cargo scanning. These systems can produce high-quality X-ray images and initiate more sensitive interrogation for SNM.