Control on the response of radiation-induced phosphors for heavy charged particles

2020 Fiscal Year Final Research Report

• Project/Area Number: 18H01911
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 31010:Nuclear engineering-related
• Research Institution: Tohoku University
• Principal Investigator: Asai Keisuke 東北大学, 工学研究科, 教授 (60231859)
• Co-Investigator(Kenkyū-buntansha): 越水 正典 東北大学, 工学研究科, 准教授 (40374962)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 重粒子線 / 線エネルギー付与 / シンチレータ / 熱蛍光体 / 励起状態間相互作用

Outline of Final Research Achievements

Unique energy deposition characteristics of heavy charged particles should be taken into account in the measurements of them. They deposit energy densely along their trajectories, and the energy density per unit length along the trajectory, i.e., linear energy tranfer (LET), is used to express the energy deposition characteristics. In this study, we revealed the basic processes responsible for the LET-dependent response of phosphors used for radiation detection. The LET-dependent of scintillators depends on the species of the excited states responsible for scintillation. On the contrary, in the case of thermally stimulated luminescence phosphors, the LET dependence can be controlled via the concentrations of the trap sites of electrons and holes.

Free Research Field

放射線工学

Academic Significance and Societal Importance of the Research Achievements

本研究で得られた知見は、学術的には、重粒子線計測に用いる放射線誘起蛍光体において、所望のLET依存性を実現するための実験指針となる。このことは、重粒子線計測における技術的基盤となる。本研究を通じた重粒子線計測の高度化により、主に重粒子線治療における線量およびその分布の計測、あるいは正確なエネルギー付与計測は、重粒子線を用いた医療の高度化に資するものである。