Presentation Information
[8a-PA2-11]Absorbed Dose Evaluation and Dose Estimation in High Dose-Rate Region Using an Nd-doped Lu2O3 Near-Infrared Scintillator and Monte Carlo Simulations
〇Satoshi Ishizawa1, Shunsuke Kurosawa2,4, Akihiro Yamaji2, Akira Yoshikawa1,3,4, Takushi Takata5, Hiroki Tanaka5 (1.IMR, Tohoku Univ., 2.Dept. Energy Eng. Sci., Nagoya Univ., 3.NICHe, Tohoku Univ., 4.Institute for Laser Eng., Osaka Univ., 5.KURNS, Kyoto Univ.)
Keywords:
Near-infrared-emitting sesquioxide scintillator,Development of a dose-rate estimation method,Monte Carlo simulation
Accurate dose evaluation in high-dose-rate radiation environments remains a significant challenge in the decommissioning of nuclear facilities. We have developed a Nd-doped Lu2O3 (Nd:Lu2O3) scintillator crystal with a high density (9.4 g/cm3), a high effective atomic number (69), and near-infrared emission around 900 nm for remote dosimetry applications. Previous radioluminescence measurements at the approximately 60 TBq of 60Co source facility of KURNS showed a power-law dependence of scintillation intensity on water-absorbed dose rate over 7-700 Gy/h. However, a change in the dose-response trend was observed around 100 Gy/h. To investigate this behavior, Monte Carlo simulations were performed using PHITS. The results showed that the fraction of scattered radiation increased from approximately 1% near the source to about 20% at the irradiation position corresponding to approximately 100 Gy/h.These results demonstrate that the fraction of scattered radiation varies significantly with irradiation position and provide fundamental information for the development of dose-rate estimation methods in high-dose-rate region.