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arXiv · 1802.01234

Validating Continuum Lowering Models via Multi-Wavelength Measurements of Integrated X-ray Emission

M. F. Kasim·J. S. Wark·S. M. Vinko
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Abstract

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.

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M. F. Kasim, J. S. Wark, S. M. Vinko. 2018-02-05. Validating Continuum Lowering Models via Multi-Wavelength Measurements of Integrated X-ray Emission. https://doi.org/10.1038/s41598-018-24410-2

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