title: Fractal structure of the distributions of air dose rates in Koriyama city in Fukushima.
abstract: The authors investigated the fractal structure of the distributions of air dose rates in Koriyama city in Fukushima using data published by the Fukushima Prefectural and Koriyama City governments. Relative frequency data of air dose rates (strength distribution) could be well fitted with a q-distribution. In the present analysis, the relative frequency decreases approximately as s for high air dose rate values, where the quantity s represents air dose rate. The fractal dimension is a function of the threshold sth of air dose rate. The fractal dimension is approximately 1.59 when sth is the average of the air dose rates in Koriyama (0.9 μSv h) and decreases with increasing the threshold: it is approximately 1.97 for sth = 0.6 μSv h and 1.40 for sth = 1.2 μSv h. These results confirm that the strength distribution behaves like a power function for high air dose rate values and that the fallout pattern can be described as a fractal.
authors.affiliation: *Department of Human Life Studies, Koriyama Women's University, Kaisei 3-25-2, Koriyama, Fukushima, 963-8503, Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Ishihara
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D017709:Fractals; D062406:Fukushima Nuclear Accident; D011829:Radiation Dosage
chemical_list: D000396:Air Pollutants, Radioactive