title: Measurements of 60Co in spoons activated by neutrons during the JCO criticality accident at Tokai-mura in 1999.
abstract: Neutron activated items from the vicinity of the place where the JCO criticality accident occurred have been used to determine the fluence of neutrons around the facility and in nearby residential areas. By using underground laboratories for measuring the activation products, it is possible to extend the study to also cover radionuclides with very low activities from long-lived radionuclides. The present study describes gamma-ray spectrometry measurements undertaken in a range of underground laboratories for the purpose of measuring (60)Co more than 2 years after the criticality event. The measurements show that neutron fluence determined from (60)Co activity is in agreement with previous measurements using the short-lived radionuclides (51)Cr and (59)Fe. Limits on contamination of the samples with (60)Co are evaluated and shown to not greatly affect the utility of neutron fluence determinations using (60)Co activation.
authors.affiliation: European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (EC-JRC-IRMM), Retieseweg, B-2440 Geel, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Gasparro
authors.forename: M
authors.initials: M
authors.lastname: Hult
authors.forename: K
authors.initials: K
authors.lastname: Komura
authors.forename: D
authors.initials: D
authors.lastname: Arnold
authors.forename: L
authors.initials: L
authors.lastname: Holmes
authors.forename: P N
authors.initials: PN
authors.lastname: Johnston
authors.forename: M
authors.initials: M
authors.lastname: Laubenstein
authors.forename: S
authors.initials: S
authors.lastname: Neumaier
authors.forename: J-L
authors.initials: JL
authors.lastname: Reyss
authors.forename: P
authors.initials: P
authors.lastname: Schillebeeckx
authors.forename: H
authors.initials: H
authors.lastname: Tagziria
authors.forename: G
authors.initials: G
authors.lastname: Van Britsom
authors.forename: R
authors.initials: R
authors.lastname: Vasselli
mesh_terms: D002860:Chromium Radioisotopes / Q000032:analysis; D003037:Cobalt Radioisotopes / Q000032:analysis; D003297:Cooking and Eating Utensils; D004781:Environmental Exposure; D004784:Environmental Monitoring; D006207:Half-Life; D007564:Japan; D009502:Neutrons; D011210:Power Plants; D011634:Public Health; D018788:Radioactive Hazard Release; D013051:Spectrometry, Gamma; D013232:Steel
chemical_list: D002860:Chromium Radioisotopes; D003037:Cobalt Radioisotopes; D013232:Steel