Hu N, Tanaka H, Takata T, Endo S, Masunaga S, Suzuki M, Sakurai Y
Graduate School of Engineering, Kyoto University, Kyoto, Japan.
Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan.
Appl Radiat Isot. 2020 Jul;161:109148. doi: 10.1016/j.apradiso.2020.109148. Epub 2020 Mar 30.
The aim of this paper is to validate the microdosimetric functionality of the Monte Carlo code, PHITS, and verify its use for estimating dose and RBE for radiobiological studies performed at Kyoto University Institute for Integrated Radiation and Nuclear Science (KURNS). Lineal energy spectra produced by the KUR mixed irradiation mode were measured with a tissue equivalent proportional counter (TEPC) place in free air. The Monte Carlo calculation showed a good agreement with the measured data. In the second part of the study, a realistic set-up of a typical in-vivo radiobiological experiment was simulated with PHITS and the simulation results were compared against TLD and gold foil activation measurements. The Monte Carlo simulation results and the measured data showed an agreement within 3%. The calculated RBE also showed a close value to clinically utilised values. This study shows that PHITS can be utilised to evaluate thermal neutron fluxes and gamma ray absorbed dose rates inside a tumour like medium.
本文的目的是验证蒙特卡罗代码PHITS的微剂量功能，并验证其在估算京都大学综合辐射与核科学研究所（KURNS）进行的放射生物学研究中的剂量和相对生物效应（RBE）方面的应用。用置于自由空气中的组织等效正比计数器（TEPC）测量了KUR混合辐照模式产生的线能量谱。蒙特卡罗计算结果与测量数据吻合良好。在研究的第二部分，用PHITS模拟了一个典型的体内放射生物学实验的实际设置，并将模拟结果与热释光剂量计（TLD）和金箔活化测量结果进行了比较。蒙特卡罗模拟结果与测量数据的吻合度在3%以内。计算得到的RBE值也与临床应用值相近。本研究表明，PHITS可用于评估肿瘤样介质内的热中子通量和γ射线吸收剂量率。
