Quantitative analysis of ionization quenching in CaF:Ce using PHITS track-structure simulations

Hirata, Yuho   ; Kai, Takeshi   ; Ogawa, Tatsuhiko   ; Matsuya, Yusuke  ; Sato, Tatsuhiko   ; Watanabe, Kenichi*; Kato, Takumi*; Kawaguchi, Noriaki*; Yanagida, Takayuki*

CaF:Ce has a high potential to be used as a dosimeter due to its high optically stimulated luminescence (OSL) intensity. However, when phosphors such as CaF:Ce are irradiated with swift ions, the OSL intensity per dose decreases due to quenching effects. Traditionally, quenching effects in phosphors have been evaluated based on energy deposition density, using linear energy transfer (LET) as a metric. However, the relationship between quenching effects and LET varies with ion type, complicating unified evaluations. The track structure in PHITS can precisely simulate the radiation interactions. In this study, we simulated the detector response of CaF:Ce irradiated with swift-ions and compared these results with experimental data. The comparison suggests that the quantum yield of OSL is a critical parameter influencing the quenching effect in CaF:Ce. These findings are expected to contribute to the development of improved phosphor detectors.