Irradiation test of HAFM and tag gas samples at the standard neutron field of "YAYOI"

not registered

To check the accuracy of helium accumulation neutron fluence monitoring (HAFM) technique and the applicability of tag gas activation analysis to fast reactor failed fuel detection, these samples were irradiated at the standard neutron field of the fast neutron source reactor "YAYOI" (Nuclear Engineering Research Laboratory, University of Tokyo). The HAFM samples of 93% enriched B powder of 1 mg contained in a V capsule were set up in the reactor core center (Glory hole :Gy) and another samples including V encapsulated natural B powder of 10 mg, natural B chips and 96% enriched LiF thermoluminescence dosimeters were in the leakage neutron field from the reactor core (Fast column :FC). These neutron fields were monitored by the activation foils consisting of Al, Fe, Co, Ni, Cu, Ti, In, Au, U, Np etc., which were used to derive the neutron flux and spectrum. At the end of March in 1996, the irradiated neutron fluence in the energy more than 0.1Mev reached up to 1.110 n/cm at Gy and 5.410 n/cm at FC, respectively. Two kinds of tag gas samples, which are the mixed gases of isotipically adjusted Xe and Kr contained in stainless steel (SUS) capsules, were irradiated twice at Gy; one is up to 9kWh and the other 7kWh, and after the irradiation, -ray spectra were measured for each sample. Through comparison with the -ray spectrum from dummy capsule of no tag gas, the -ray peaks of Kr, Xe etc., which would be produced from tag gas activation, were able to be clearly identified.