Speaker
Dr
Hidetoshi Kikunaga
(Tohoku University, Japan)
Description
The Fukushima 1 Nuclear Power Plant suffered major damage from the 2011 off the Pacific coast of Tohoku Earthquake and subsequent tsunami on March 11, 2011 and released various radionuclides. Monitoring of environmental radioactivity should provide important information on the behavior of the radionuclides.
To investigate the time variation of atmospheric activity concentration of radiocesium, we have regularly collected aerosol particle samples at Mikamine, Sendai from March 15, 2011 to present. The aerosol particle was collected on a cellulose-glass fiber (Advantec, HE-40T). The radioactivity of radiocesium in the aerosols collected was determined by gamma-ray spectrometry using HP-Ge detectors. The atmospheric activity concentrations of radiocesium were calculated as the ratio between the radiocesium activity in the aerosol particle sample and the total volume of sampling air. As a result, it was found that the maximum activity concentrations of radiocesium were recorded in March 20-21, 2011 and then the atmospheric activity concentrations of radiocesium roughly decreased with a half-life of 10 - 30 d.
In addition, radioactivity distribution on the collection filters used in the measurement was measured by using imaging plate technique. The relation between the monitoring results on the concentration of radiocesium in the air and the imaging plate results are discussed in the presentation.
Primary author
Dr
Hidetoshi Kikunaga
(Tohoku University, Japan)
Co-authors
Dr
Fusashi Miyahara
(Research Center for Electron Photon Science, Tohoku University)
Hirohito Yamazaki
(Research Center for Electron Photon Science, Tohoku University)
Dr
Hisako Fujimura
(Research Center for Electron Photon Science, Tohoku University)
Mr
Ikurou Nagasawa
(Research Center for Electron Photon Science, Tohoku University)
Mr
Kazue Matsuda
(Research Center for Electron Photon Science, Tohoku University)
Mr
Ken Takahashi
(Research Center for Electron Photon Science, Tohoku University)
Mr
Kenichi Nanbu
(Research Center for Electron Photon Science, Tohoku University)
Dr
Koutaku Suzuki
(Research Center for Electron Photon Science, Tohoku University)
Dr
Manabu Miyabe
(Research Center for Electron Photon Science, Tohoku University)
Mr
Masayuki Hiraga
(Research Center for Electron Photon Science, Tohoku University)
Mr
Shigenobu Takahashi
(Research Center for Electron Photon Science, Tohoku University)
Dr
Shigeru Kashiwagi
(Research Center for Electron Photon Science, Tohoku University)
Dr
Takatsugu Ishikawa
(Research Center for Electron Photon Science, Tohoku University)
Dr
Toshiya Muto
(Research Center for Electron Photon Science, Tohoku University)
Tsutomu Ohtsuki
(Tohoku University)
Mr
Yoshinobu Shibasaki
(Research Center for Electron Photon Science, Tohoku University)
Ms
Yumi Sugawara
(Research Center for Electron Photon Science, Tohoku University)