An estimation of fast neutron flux by (,α) reaction

Measurements of 60Co in spoons activated by neutrons during the JCO criticality accident at Tokai-mura in 1999

“…Three spoons (Sns 8, St 16 and Sns 13), however, present a higher massic activity. Sns 8 was sampled from east of the JCO centre, and the higher fluence in this 2000), Kofuji et al (2000) and Takada and Hoshi (2000). The very low value of the 60 Co activity of spoon Sns 8C is therefore surprising and has not been explained.…”

“…In the first sampling campaign, gold items were borrowed and used for estimating the thermal neutron fluence (Komura et al, 2000b). Table salt was also taken to determine the fast neutron fluence which induced the reaction 35 Cl(n,a) 32 P (Kofuji et al, 2000). During the second sampling campaign, stainless steel samples (mainly spoons) were collected from residences (Endo et al, 2000;Hult et al, 2002).…”

Radiochemical Approach to the JCO Criticality Accident in Tokai-mura, 1999 -An Overview of the Radiochemistry Group-

“…On the other hand, our team, which was composed of members of a number of universities as well as national and prefectural institutes, tried to assess the environmental impact of the accident from NGO-like policy. A variety of techniques were applied, such as in-situ Ge spectrometry 6) , gamma-and beta-ray measurements of neutron-induced nuclides and fission products in various samples collected in the JCO campus and in Tokai-mura and Naka-machi [7][8][9][10][11][12][13][14][15] , TL measurement 16) etc. The measured data were used for theoretical simulation based on neutron transfer model 12,17,18) .…”