Arktis’ detectors can also be installed in doorways or used in luggage-handling locations. They work entirely passively but are different from Geiger counters, the best-known radiation detectors. Special material inside Arktis’ devices reacts when it is exposed to the subatomic particles emitted by radioactive substances. This reaction produces a tiny amount of light—scintillation—which is measured by sensors and subsequently processed by computer algorithms.
Because different radioactive substances prompt distinct emissions of light, it’s often possible to tell immediately what kind of material has been detected—an isotope of uranium or cobalt, say. Panniello explains that his company
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