Demonstration of the nuclear resonance fluorescence integral resonance transmission method for NDA of debris of melted nuclear fuel

溶融燃料デブリに対する積分光共鳴吸収法を用いた非破壊分析の実証

Angell, C.; 早川 岳人; 静間 俊行; 羽島 良一; Quiter, B. J.*; Ludewigt, B. L.*; Karwowski, H.*; Rich, G.*

Angell, C.; Hayakawa, Takehito; Shizuma, Toshiyuki; Hajima, Ryoichi; Quiter, B. J.*; Ludewigt, B. L.*; Karwowski, H.*; Rich, G.*

Non-destructive assay (NDA) of Pu in spent nuclear fuel is possible using the isotope-specific nuclear resonance fluorescence (NRF) integral resonance transmission (IRT) method. The IRT method measures the absorption of photons from a quasi-monoenergetic -ray beam due to all resonances in the energy width of the beam. According to calculations the IRT method could greatly improve assay times for Pu in nuclear fuel. To demonstrate and verify the IRT method, we measured the IRT signature in a simulant material, Ta, whose nuclear resonant properties are similar to those of Pu. Measurements were made at beam energies of 2.27 and 2.75 MeV, using metallic Ta for both the absorption and scattering targets. The scattered radiation was measured using HPGe and LaBr detectors. The results confirm the validity of the IRT method and a similar result is expected on Pu.