title: Estimation of immediate fallout after the accident at Fukushima Daiichi Nuclear Power Plant by using HPGe detector and EGS5 code.
abstract: After the accident at the Fukushima Daiichi nuclear power plant, we managed to carry out emergency measurements of the radioactive fallout. The included nuclides were identified via gamma-ray spectrometry using an HPGe detector. Quantifications of each radionuclide in the fallout were determined based on the efficiency calibrations and relevant corrections. The collected samples had a variety of shapes, densities, and compositions. EGS5 Monte Carlo code was used for the flexible estimation of these parameters. The measurement results show the temporal changes in the fallout quantity about a month after the accident.
authors.affiliation: National Metrology Institute of Japan, Japan; The Graduate University for Advanced Studies (Sokendai), Japan. y.unno@aist.go.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Unno
authors.forename: Akira
authors.initials: A
authors.lastname: Yunoki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sato
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hino
mesh_terms: D000398:Air Pollution, Radioactive / Q000032:analysis / Q000706:statistics & numerical data*; D000465:Algorithms; D003198:Computer Simulation; D062406:Fukushima Nuclear Accident; D007564:Japan; D015233:Models, Statistical; D009792:Oceans and Seas; D011829:Radiation Dosage; D011847:Radioactive Fallout / Q000032:analysis / Q000706:statistics & numerical data*; D011868:Radioisotopes / Q000032:analysis*; D018570:Risk Assessment / Q000379:methods; D012984:Software; D013051:Spectrometry, Gamma / Q000295:instrumentation* / Q000379:methods
chemical_list: D011847:Radioactive Fallout; D011868:Radioisotopes
keywords: EGS5 code; Fukushima nuclear power plant accident; Gamma-ray spectrometry; HPGe detector; Radioactive fallout; Temporal transition