Processes of $K$-shell ionization and accompanying characteristic x-ray radiation (CXR) by high-energy electrons moving through a multifoil copper target are considered. Expressions describing the main characteristics of these processes are derived. It is shown that the average $K$-shell ionization cross section in the target is not defined just by the target material and the electron energy, but also depends on the number of foils in the target, their thickness, and separation between them. The corresponding CXR yield is therefore not unambiguously defined by the aggregated target thickness, but depends on the above parameters as well. It is demonstrated that the average $K$-shell ionization cross section in a multifoil target can be several times larger than the conventional cross section of this process without the density effect impact. This results in a considerable enhancement of CXR yield from the multifoil target compared to the case of electron incidence upon a single foil of the same aggregated thickness. A comparison of the CXR yield in the considered case with the yields of some other types of x-ray emission in multifoil targets is made.

中文翻译：

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多箔靶中的K壳电离和高能电子的特征X射线辐射

的过程 $ķ$考虑了通过多箔铜靶移动的高能电子引起的壳电离和伴随的特征X射线辐射（CXR）。得出描述这些过程主要特征的表达式。结果表明，平均$ķ$靶中的壳电离截面不仅由靶材料和电子能决定，还取决于靶中箔的数量，其厚度以及它们之间的间隔。因此，相应的CXR产量并非由总目标厚度明确定义，而是也取决于上述参数。据证明，平均$ķ$多箔靶中的壳电离截面可以比该方法的常规截面大几倍，而不会影响密度效应。与在相同聚集厚度的单个箔片上电子入射的情况相比，这大大提高了多箔靶材的CXR产量。将考虑情况下的CXR产量与多层箔靶中某些其他类型的X射线发射的产量进行比较。