基于EGSnrc MP模拟计算X射线在重金属和硅界面的剂量增强因子

CALCULATION OF THE DOSE ENHANCEMENT FACTOR TO W-Si AND Ta-Si INTERFACE BY EGSnrcMP

当X射线入射到不同材料组成的界面时,在低Z材料的一侧将产生剂量增强。本文介绍了界面剂量增强效应的基本原理,并用蒙特卡罗程序EGSnrcMP模拟计算了钨和硅、钽和硅界面的剂量增强因子。计算结果表明,在X射线能量为30~200 keV时,界面附近硅一侧存在较大的剂量增强效应。

The dose would be enhanced in low Z material when X-ray enters the interface which is constructed with different materials. The mechanism of dose enhancement is introduced in this article, and the dose enhancement factors of W-Si, Ta-Si interface are calculated in the article. The calculated results demonstrate that there exists a stronger dose-enhancement in the Si side near the interface when the energy of X-ray is 30 ~ 200 keV.