放疗剂量测量中相空间数据格式的标准与转换

Standard and conversion of the phase-space data format in dose measurement of radiotherapy

相空间数据是放疗剂量测量的蒙特卡洛(Monte Carlo,MC)模拟中某一截面或某些截面处各种射线的类型、位置坐标、方向和能量等信息。相空间数据的使用是这类MC模拟的重要辅助手段。本文旨在介绍放疗剂量测量的MC模拟中相空间数据的概念和通用的国际原子能机构(IAEA)格式标准,并提出一种基于常用MC工具软件Geant4、将excel格式相空间文件转换为IAEA标准格式(phsp格式)的方法,以解决使用IAEA相空间数据格式标准,尤其是使用Geant4的研究人员在采用excel格式相空间数据时遇到的问题。通过引入一个存储并推送相空间数据的类,可以成功实现excel格式相空间文件到IAEA标准格式的转换。

Phase-space data refer to the information of the type,position,direction,and energy of particles in a plane or several planes in the Monte Carlo（MC） simulations of the radiotherapy dose measurement.As an important assistant method,the use of phase-space data facilitates the MC simulations.The paper aims to introduce the concept of phase-space data in MC simulation and the International Atomic Energy Agency（IAEA） standard of phase-space data format,and to propose a method for converting phase-space data stored in excel files to the standard IAEA format（phsp format） using Geant4,a popular MC simulation toolkit,in order to solve the problem of using phase-space data in excel format for the researcher who used the phase-space data in IAEA standard format,especially the Geant4 users.By introducing a class that temporarily stores and forwards phase-space data to Geant4,the conversion of excel format to IAEA standard format can be implemented successfully.