Regarding the chronologic evolution of accelerator-based light sources, optimization and design issues of cutting-edge-technology insertion devices (i.e., undulators, wigglers, etc.) have been a big competitive concern since the beginning of the twenty-first century. Although these sources are strongly restricted by technological limitations in terms of radiation wavelength, leading X-ray free-electron laser (FEL) facilities are spending considerable efforts to survive in this scientific competition by modifying/updating their insertion devices. In other words, even though they all generate almost identical free-electron laser pulses, advertising a “superconducting undulator based light source” in comparison with a “conventional undulator based light source” may sound more attractive for some scientists. However, in contrast to superconducting undulators, conventional undulators do not require cryogenic cooling systems resulting in a cost-effective operation as a matter of course. Under the circumstances, it is shown that generation of hard X-ray FEL pulses is feasible via unique PPM undulators driven by an electron linear accelerator (linac) within the energy range of 5–10 GeV. The results reveal good consistency with the operating X-ray FEL sources worldwide.

关于基于加速器的光源的时间演变，自二十一世纪初以来，尖端技术插入设备（即起伏器，摆动器等）的优化和设计问题一直是人们关注的重大问题。尽管这些源受到辐射波长方面的技术限制的严格限制，但是领先的X射线自由电子激光（FEL）设施正在花费大量的精力通过修改/更新其插入设备来生存在这种科学竞争中。换句话说，即使它们都产生几乎相同的自由电子激光脉冲，与“传统的基于波荡器的光源”相比，宣传“基于超导波荡器的光源”对于某些科学家来说可能更具吸引力。然而，与超导波荡器相比，常规波荡器不需要低温冷却系统，这自然导致了具有成本效益的运行。在这种情况下，已证明通过由电子线性加速器（直线加速器）在5-10 GeV的能量范围内驱动的独特PPM起伏器，可以产生硬X射线FEL脉冲。结果表明，与全球运行的X射线FEL光源具有良好的一致性。