title: Deposition of fission and activation products after the Fukushima Dai-ichi nuclear power plant accident.
abstract: 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 ((239)Np and (59)Fe) and fission products ((131)I, (134)Cs ((133)Cs), (137)Cs, (110m)Ag ((109)Ag), (132)Te, (132)I, (140)Ba, (140)La, (91)Sr, (91)Y, (95)Zr, and (95)Nb). (239)Np is the parent nuclide of (239)Pu; (59)Fe are presumably activation products of (58)Fe obtained by corrosion of cooling pipes. The results show that these activation and fission products, diffused within a month of the accident.
authors.affiliation: Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan. cshozu@mail.ecc.u-tokyo.ac.jp
authors.forename: Katsumi
authors.initials: K
authors.lastname: Shozugawa
authors.forename: Norio
authors.initials: N
authors.lastname: Nogawa
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Matsuo
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D007564:Japan; D009680:Nuclear Fission; D055848:Nuclear Power Plants; D011829:Radiation Dosage; D011834:Radiation Monitoring; D018788:Radioactive Hazard Release
chemical_list: D000396:Air Pollutants, Radioactive