JOYO impurity concentrations of radioactive nuclide data in the primary system (MK-II core)

not registered ; Saikawa, Takuya*; Masui, Tomohiko*; Arima, Toshihiro*

The experimental fast reactor "JOYO" served as the MK-II irradiation test bed core for testing fuel and material for FBR development for 18 years from 1982 to 2000. "JOYO" has no fuel failure since the initial criticality. Impurity concentrations of fission products data were accumulated in the primary argon gas and primary sodium during the MK-II core operation in order to obtain background value. 352 samples of primaly argon gas and the online gamma-ray monitor determined the fission products concentration data in the primary argon gas. In order to demonstrate the performance of the cold trap pre-filter, the cold trap pre-filter function confirmation tests were carried out in 1995 during 10 annual inspection. The Cs concentration data in the primary sodium were determined by 10 samples of primary sodium. The in core tag gas release tests were carried out during 29th cycle to 31st cycle. The online gamma-ray monitor determined the activation tag gas concentration data in the primary argon gas These fission products concentration data, the cold trap pre-filter function confirmation tests data and in core tag gas release tests data were compiled, which were recorded on CD-ROM for user convenience.