Detecting nuclear radiation at a distance

Maintaining international nuclear security requires tracking and monitoring fissile materials , such as plutonium and uranium. Standoff radiation detectors, which can measure radioactivity from afar, play a key role in those efforts. However, the distance at which current technologies can detect radiation is limited. Now a team of scientists led by physicists at the University of Maryland, College Park, has demonstrated the feasibility of a laser-based method with the potential to detect radiation from further distances ( Phys. Rev. Appl. 2025, DOI: 10.1103/PhysRevApplied.23.034004). Using an infrared pulsed carbon dioxide laser, project leader Howard Milchberg and his team showed that they could detect low levels of α radiation from a polonium-210 source sitting 10 m away from the laser source. For this proof-of-principle work, Milchberg’s team was limited by the length of the laser lab they were working in but they expect the method to be scalable to distances greater than 100