1. Center for Environmental Remote Sensing, Chiba University, Chiba, Japan
2. Radiation Measurement Research Group, National Institutes for Quantum Science and Technology, Chiba, Japan
3. Institute for Advanced Academic Research, Chiba University, Chiba, Japan
4. Institute of Environmental Radioactivity, Fukushima University, Fukushima, Japan
5. Graduate School of Science and Engineering, Chiba University, Chiba, Japan
6. Institute for Safety Problems of Nuclear Power Plants, National Academy of Sciences of Ukraine, Kyiv, Ukraine
7. Ukrainian Hydrometeorological Institute, National Academy of Sciences of Ukraine, Kyiv, Ukraine
8. Chernobyl Ecocentre, State Agency of Ukraine on Exclusion Zone Management, Chornobyl, Ukraine