X-ray absorption spectroscopy is a well-accepted diagnostic for warm dense matter experimental studies. It requires a short-lived X-ray source of sufficiently high emissivity and without characteristic lines in a spectral range of interest. In the present work, we discuss choosing its optimum material and thickness to get a bright source in the wavelength range of 2-6 A (~2-6 keV) considering relatively low-Z elements. We demonstrate that the highest emissivity of solid aluminium and silicon foil targets irradiated with a 1 ps high-contrast sub-kJ laser pulse is achieved when the target thickness is close to 10 μm. An outer plastic layer can increase the emissivity even further.

中文翻译：

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根据 WDM 吸收光谱要求优化基于激光等离子体的 X 射线源

X 射线吸收光谱是一种广为接受的热致密物质实验研究诊断方法。它需要一个短寿命的 X 射线源，其发射率足够高，并且在感兴趣的光谱范围内没有特征线。在目前的工作中，我们讨论了选择其最佳材料和厚度以在 2-6 A (~2-6 keV) 的波长范围内考虑相对低 Z 元素的明亮光源。我们证明，当目标厚度接近 10 μm 时，使用 1 ps 高对比度亚 kJ 激光脉冲照射的固体铝和硅箔目标的发射率最高。外塑料层可以进一步提高发射率。