Academic paper : Deposition of fission and activation products after the Fukushima Dai-ichi nuclear power plant accident
Deposition of fission and activation products after the Fukushima Dai-ichi nuclear power plant accident
Katsumi Shozugawaa, Corresponding author contact information, E-mail the corresponding author,
a Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan
b Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
Received 22 August 2011. Revised 24 December 2011. Accepted 1 January 2012. Available online 20 January 2012.
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. end quote