Kasim M F, Wark J S, Vinko S M
Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
Sci Rep. 2018 Apr 19;8(1):6276. doi: 10.1038/s41598-018-24410-2.
X-ray emission spectroscopy is a well-established technique used to study continuum lowering in dense plasmas. It relies on accurate atomic physics models to robustly reproduce high-resolution emission spectra, and depends on our ability to identify spectroscopic signatures such as emission lines or ionization edges of individual charge states within the plasma. Here we describe a method that forgoes these requirements, enabling the validation of different continuum lowering models based solely on the total intensity of plasma emission in systems driven by narrow-bandwidth x-ray pulses across a range of wavelengths. The method is tested on published Al spectroscopy data and applied to the new case of solid-density partially-ionized Fe plasmas, where extracting ionization edges directly is precluded by the significant overlap of emission from a wide range of charge states.
X射线发射光谱学是一种成熟的技术，用于研究致密等离子体中的连续谱降低。它依靠精确的原子物理模型来稳健地再现高分辨率发射光谱，并取决于我们识别等离子体中各个电荷态的发射线或电离边缘等光谱特征的能力。在这里，我们描述了一种无需这些要求的方法，仅基于在一系列波长上由窄带宽X射线脉冲驱动的系统中等离子体发射的总强度，就能验证不同的连续谱降低模型。该方法在已发表的铝光谱数据上进行了测试，并应用于固体密度部分电离铁等离子体的新情况，在这种情况下，由于来自广泛电荷态的发射存在显著重叠，直接提取电离边缘是不可能的。
