title: Tracing radioactivity from Fukushima in the Northern Pacific Ocean.
abstract: Following the accident at the Fukushima Daiichi nuclear power plant, a campaign of sampling and measuring anthropogenic radionuclides in North Pacific seawater was set up. The main aim was to study natural processes using these radionuclides as tracers. Because of dilution, the activities of anthropogenic radionuclides at long range were very low and their measurement required advanced pre-concentration techniques and underground gamma-ray spectrometry. Data and metrological aspects of the measurements using HPGe-detectors are presented and discussed.
authors.affiliation: Institute of Environmental Radioactivity, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Aoyama
authors.affiliation: European Commission, Joint Research Centre (JRC), Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel, Belgium. Electronic address: Mikael.hult@ec.europa.eu.
authors.forename: M
authors.initials: M
authors.lastname: Hult
authors.affiliation: Low Level Radioactivity Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Nomi, Ishikawa 923-1224, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hamajima
authors.affiliation: European Commission, Joint Research Centre (JRC), Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Lutter
authors.affiliation: European Commission, Joint Research Centre (JRC), Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Marissens
authors.affiliation: European Commission, Joint Research Centre (JRC), Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Stroh
authors.affiliation: European Commission, Joint Research Centre (JRC), Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel, Belgium.
authors.forename: F
authors.initials: F
authors.lastname: Tzika
mesh_terms: D001681:Biological Assay / Q000379:methods*; D004784:Environmental Monitoring / Q000379:methods; D062406:Fukushima Nuclear Accident; D010140:Pacific Ocean; D010933:Plankton / Q000737:chemistry*; D011868:Radioisotopes / Q000032:analysis*; D011874:Radiometry / Q000379:methods*; D015203:Reproducibility of Results; D012623:Seawater / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013051:Spectrometry, Gamma / Q000379:methods; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D011868:Radioisotopes; D014875:Water Pollutants, Radioactive
keywords: Gamma-ray spectrometry; Ocean currents; Oceanography; Plankton; Underground laboratory