Investigation of the characterization evaluation method for neutron fields of accelerator based BNCT and facility comparison

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K20360
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0202:Condensed matter physics, plasma science, nuclear engineering, earth resources engineering, energy engineering, and related fields
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Manage Seiya 国立研究開発法人産業技術総合研究所, 計量標準総合センター, 研究員 (40910005)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: ホウ素中性子捕捉療法(BNCT) / 中性子計測 / アンフォールディング

Outline of Final Research Achievements

Boron Neutron Capture Therapy (BNCT) is an emerging cancer treatment that utilizes neutron radiation. To ensure a safe and effective therapy, it is crucial to evaluate the neutron field employed during treatment. In this study, we investigated suitable measurement techniques for assessing the neutron field. Specifically, we focused on measuring the thermal neutron flux within a water phantom, which is a simulation of the human body and has been traditionally used for quality assurance in BNCT. By applying the technique called "unfolding," which solves the inverse problem of depth distribution of thermal neutron detector counts in the water phantom, we developed a system capable of characterizing the neutron spectral fluence rate across a wide energy range. Operational tests were conducted on the system to validate its accuracy.

Free Research Field

放射線計測

Academic Significance and Societal Importance of the Research Achievements

本研究では、従来から測定が行われていた水ファントム中における熱中性子検出器での測定に着目し、その測定結果から中性子スペクトラルフルエンス率を導出する手法を開発した。従来の測定は、中性子照射装置の定常性を確認のためにのみ行われていたが、本手法を用いることで治療の有効性を確認するための重要な物理量を導出することが可能である。また、本手法は従来の測定結果に対し、解析手順を加えるのみであり、現場における実装が容易であると予想される。