Kawrakow I
National Research Council, Ottawa, ON, Canada.
Med Phys. 2000 Mar;27(3):485-98. doi: 10.1118/1.598917.
In this report a new EGS4 version, called EGSnrc to reflect the substantial changes made to the original code is reported, which incorporates a new any-angle multiple elastic scattering theory, an improved electron-step algorithm, a correct implementation of the fictitious cross section method for sampling distances between discrete interactions, a more accurate evaluation of energy loss, as well as an exact boundary crossing algorithm. It is demonstrated that EGSnrc allows for an artifact free Monte Carlo simulation of ion chamber response and backscattering, situations that have been considered in the past as the two of the most stringent tests of condensed history Monte Carlo codes. A detailed discussion of the effect of the various components of the condensed history simulation of electron transport on the simulated ion chamber response is given in the accompanying paper.
在本报告中，介绍了EGS4的一个新版本，称为EGSnrc，以体现对原始代码所做的重大更改。该版本纳入了一种新的任意角度多重弹性散射理论、一种改进的电子步长算法、用于离散相互作用间距离采样的虚拟截面方法的正确实现、对能量损失更精确的评估以及一种精确的边界穿越算法。结果表明，EGSnrc能够对电离室响应和背散射进行无伪影的蒙特卡罗模拟，而过去一直认为这两种情况是对凝聚历史蒙特卡罗代码最严格的两项测试。随附论文中对电子输运凝聚历史模拟的各个组件对模拟电离室响应的影响进行了详细讨论。
