Research for spectroscopy of fuel debris using superconducting phase transition edge sensor microcalorimeter; Measurement experiment and simulated calculation (Joint research)

Takasaki, Koji  ; Yasumune, Takashi  ; Onishi, Takashi  ; Nakamura, Keisuke  ; Ishimi, Akihiro ; Ito, Chikara   ; Osaka, Masahiko  ; Ono, Masashi*; Hatakeyama, Shuichi*; Takahashi, Hiroyuki*; Maehata, Keisuke*; Maeda, Makoto*; Damayanthi, R. M. T.*; Sugita, Takeshi*

In the Fukushima Daiichi Nuclear Power Plant, it is assumed that the core fuels melted partially or wholly, and the normal technique of accounting for a fuel assembly is not applicable. Therefore, it is necessary to develop the transparent and rational technique of accounting in the process of collection and storage of fuel debris. In this research, an application of the superconducting phase Transition Edge Sensor microcalorimeter (TES microcalorimeter) is studied for the accounting of nuclear materials in the fuel debris. It is expected that the detailed information of nuclear materials and fission products in fuel debris is obtained by using a high-resolution characteristic of TES microcalorimeter. In this report, the principle of TES microcalorimeter, the measurement experiment using TES in JAEA, and the simulated calculation using the EGS5 code system are summarized.