[1I01-06] 燃料デブリ特性評価

[1I01] The possible use of short half-life noble gas fission products for measurement of criticality and identification of plutonium in fuel debris canister

*Eka Sapta Riyana¹, Keisuke Okumura¹, Masahiro Sakamoto¹, Taichi Matsumura¹, Kenichi Terashima¹ (1. JAEA)

キーワード：Depletion calculation, Subcritical System, Fuel Debris Canister, Mixed Oxide (MOX) fuel, Monte Carlo Calculation, Short Half-life Fission Products

Fuel debris has inherent neutron sources due to mostly spontaneous fissions. Therefore, the fuel debris inside a canister can be seen as a subcritical system with fixed neutron source. A depletion calculation for the fuel debris inside the canister has been performed. The calculation results show the relation between the activity ratio of short half-life noble gas fission products (FPs) ⁸⁸Kr-to-¹³⁵Xe and the effective neutron multiplication factor (k_eff). The results also show the possible use of the activity ratio to identify fuel debris caused from UO₂ or MOX fuels.