Abstract The effective atomic number of multifunctional composite materials has been determined experimentally by adopting backscattering of beta particles technique. A 2.2 MeV beta particles emitted from a weak radioactive beta source were allowed to backscatter at an angle of 150 degrees from the elemental and composite targets. The backscattered beta particles were detected with the end window Geiger–Mueller gas detector. Experimentally, it is observed that the yield of the backscattered beta particle increases with increasing the target thickness for pure elements. Then, the yield of backscattering beta particle saturates after a certain thickness. The linear fit between the saturated thickness and the atomic number of the elemental target has been used to determine the effective atomic number of composite materials. The determined Zeff values of multifunctional composite targets have been compared with the values obtained by Monte Carlo method and computational codes.

中文翻译：

---

使用背散射β粒子测定多功能材料的有效原子序数——一种新方法

摘要 采用β粒子背向散射技术，通过实验确定了多功能复合材料的有效原子序数。允许从弱放射性 β 源发射的 2.2 MeV β 粒子以 150 度角从元素和复合目标反向散射。使用端窗盖革-穆勒气体检测器检测背向散射的 β 粒子。通过实验，观察到背散射 β 粒子的产率随着纯元素目标厚度的增加而增加。然后，背向散射β粒子的产率在一定厚度后饱和。饱和厚度与元素靶的原子序数之间的线性拟合已被用于确定复合材料的有效原子序数。