The particle and heavy ion transport code system (PHITS) is a general-purpose Monte Carlo radiation transport simulation code. It has the ability to handle diverse particle types over a wide range of energy. The latest PHITS development enables the generation of track structure for proton and carbon ions (¹H⁺, ¹²C⁶⁺) based on the algorithms in the KURBUC code, which is considered as one of the most verified track-structure codes worldwide. This ion track-structure mode is referred to as the PHITS-KURBUC mode. In this study, the range, radial dose distributions, and microdosimetric distributions were calculated using the PHITS-KURBUC mode. Subsequently, they were compared with the corresponding data obtained from the original KURBUC and from other studies. These comparative studies confirm the successful inclusion of the KURBUC code in the PHITS code. As results of the synergistic effect between the macroscopic and microscopic radiation transport codes, this implementation enabled the detailed calculation of the microdosimetric and nanodosimetric quantities under complex radiation fields, such as proton beam therapy with the spread-out Bragg peak.

粒子和重离子传输代码系统 (PHITS) 是一种通用的蒙特卡罗辐射传输模拟代码。它有能力在很宽的能量范围内处理不同的粒子类型。最新的 PHITS 开发能够生成质子和碳离子 ( ¹ H ⁺ , ¹² C ⁶⁺) 基于 KURBUC 代码中的算法，该代码被认为是全球最经验证的轨道结构代码之一。这种离子轨道结构模式称为 PHITS-KURBUC 模式。在本研究中，使用 PHITS-KURBUC 模式计算了范围、径向剂量分布和微剂量分布。随后，将它们与从原始 KURBUC 和其他研究中获得的相应数据进行了比较。这些比较研究证实了 KURBUC 代码成功地包含在 PHITS 代码中。作为宏观和微观辐射传输代码之间协同效应的结果，这种实现能够在复杂辐射场下详细计算微剂量和纳米剂量，例如具有展开布拉格峰的质子束治疗。