Detecting radioactive materials from afar is not possible today. Take the typical Geiger counter for example. In order to detect 1 milliCurie of Cobalt-60, it needs to be within about four meters of the radioactive source, and it’s inefficient at measuring lower levels of radioactivity.
Given the frequency of accidents involving nuclear power plants around the globe, and the possibility of terrorists using dirty nuclear bombs as a weapon, there is an increasing need to detect radioactive materials remotely in order to protect those doing the detecting and to warn residents in areas close by. (Think of accident sites such as the Fukushima Daiichi nuclear plant, which is currently undergoing a challenging and decades’ long decommissioning.)
Researchers at Ulsan National Institute of Science and Technology (UNIST) in Ulsan, South Korea, have successfully demonstrated an experimental method for real-time remote detection of substances that emit hazardous radiation. Their technique is based on induced plasma breakdown by a high power electromagnetic (EM) wave source. Their results were published in the May issue of Nature Communications.
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Because the threshold EM power for plasma breakdown in air was higher than the maximum gyrotron power available, the researchers conducted the air breakdown experiment only in the presence of radioactivity. They were able to detect 0.5 micrograms of cobalt-60 at 120 centimeters distance—the maximum distance allowed by the lab set-up.
Professor EunMi Choi, the leader of the group, told IEEE Spectrum that, “As soon as the next round of funding is secured, we plan to test the method outside the lab with a target range of about 100 meters.”
Read more at EnergywiseEnergyNuclear Detecting Hazardous Radiation from Afar Now Possible