A research group led by Professor Atsushi Kataoka and Professor Hiroshi Okouchi of the Waseda University Faculty of Science and Engineering used a camera mounted on a drone in Namie Town, Fukushima Prefecture, which has become a difficult area to return home due to the Fukushima Daiichi Nuclear Power Station accident caused by the Great East Japan Earthquake. I succeeded in shooting gamma rays from the sky.Since hot spots could be confirmed more easily than measuring on the ground, it is said that it will be useful for improving the efficiency of decontamination work and investigations in the future.
According to Waseda University, in April and September 2015, the research group equipped a commercially available drone with a lightweight Compton camera for gamma ray measurement and a laptop computer, which took pictures of the ground from 4 to 9 meters above the ground and gamma rays. I investigated the situation of.
With this camera, you can shoot and image the inside of a circle with a diameter of 1 meters at a time.The image of the Namie High School Tsushima Branch School ground accurately captured the location of the expanded hotspot.Similarly, accurate hotspot distribution was found in forests with shields.
As a result of advancing dosimetry from the ground to 150 meters above the ground at the same time as the shooting, it was also possible to measure that the dose gradually decreased as the altitude increased. Comparing the measurement results in April and September, the dose was lower in September.
In Fukushima Prefecture, 70% of the prefecture's land is forest, and decontamination of forests is a major issue in the areas affected by the nuclear accident, such as Namie Town.The research group believes that the use of drones is effective in confirming the status of pollution over a wide area.
