Laser-Based X-Ray Can Help Detect Smuggled Uranium
By Engineering360 News Desk | January 11, 2016A portable laser-based X-ray machine could enable detection of smuggled nuclear materials, potentially aiding cargo ship inspections before they reach port.
Physicists at the Diocles Extreme Light Laboratory at the University of Nebraska-Lincoln have used a laser-driven X-ray to produce an image of a uranium disk no bigger than a stack of coins and hidden between 3-inch steel panels.
The researchers demonstrated that laser-produced X-rays can detect an even smaller amount of uranium than the minimum required by current inspection standards (1 kilogram) and can penetrate steel thicker than the walls of cargo containers.
X-ray laser imaged the uranium disk hidden within a steel casing. Image credit: Craig Chandler/UN-Lincoln.Inspectors need tools to help find nuclear materials hidden behind thick shielding or smuggled inside any of the 100 million-plus cargo containers shipped globally each year. Uranium ranks among the easiest nuclear materials to obtain and hide, says Donald Umstadter, director of the Diocles Laboratory and leader of the project.
Unlike previous sources of similar X-rays, which require stadium-sized facilities, this X-ray source is portable and could be moved in a semi-trailer truck, increasing its potential for use as a nuclear site inspection tool.
Just as a laser pointer can be directed across a large auditorium, the technology can shoot a thin X-ray beam long distances. Even so, it emits lower levels of radiation than conventional X-rays, making it safer for use around workers and bystanders.
Umstadter and his team announced in 2013 that they had developed the laser-driven X-ray source, referred to as a laser-wakefield-accelerator-driven inverse-Compton-scattering source. At the time, they said it not only would increase the availability of sophisticated forms of X-rays needed for physics research, but also could be used to detect hidden or smuggled nuclear materials. Since then, Umstadter and his team have worked to prove that the X-ray machine would, in fact, serve those purposes.
The next step is to improve the performance and precision of the X-ray device.