Deposition of fission and activation products after the Fukushima Dai-ichi nuclear power plant accident

Shozugawa, Katsumi; Nogawa, Norio; Matsuo, Motoyuki

Deposition of fission and activation products after the Fukushima Dai-ichi nuclear power plant accident

2012

Shozugawa, Katsumi | Nogawa, Norio | Matsuo, Motoyuki

The Great Eastern Japan Earthquake on March 11, 2011, damaged reactor cooling systems at Fukushima Dai-ichi nuclear power plant. The subsequent venting operation and hydrogen explosion resulted in a large radioactive nuclide emission from reactor containers into the environment. Here, we collected environmental samples such as soil, plant species, and water on April 10, 2011, in front of the power plant main gate as well as 35 km away in Iitate village, and observed gamma-rays with a Ge(Li) semiconductor detector. We observed activation products (²³⁹Np and ⁵⁹Fe) and fission products (¹³¹I, ¹³⁴Cs (¹³³Cs), ¹³⁷Cs, ¹¹⁰ᵐAg (¹⁰⁹Ag), ¹³²Te, ¹³²I, ¹⁴⁰Ba, ¹⁴⁰La, ⁹¹Sr, ⁹¹Y, ⁹⁵Zr, and ⁹⁵Nb). ²³⁹Np is the parent nuclide of ²³⁹Pu; ⁵⁹Fe are presumably activation products of ⁵⁸Fe obtained by corrosion of cooling pipes. The results show that these activation and fission products, diffused within a month of the accident.

Afficher plus [+]