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arXiv · 2507.02341

Impact of super-Gaussian electron distributions on plasma K-shell emission

H. P. Le·E. V. Marley·H. A. Scott
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Abstract

Electron distributions in laser-produced plasmas will be driven toward a super-Gaussian distribution due to inverse bremsstrahlung absorption [Langdon, Phys. Rev. Lett. 44, 575 (1980)]. Both theoretical and experimental evidence suggest that fundamental plasma properties are altered by the super-Gaussian distribution. This paper examines how the super-Gaussian distribution affects the ionization balance and K-shell emission of atomic plasmas, utilizing approximate formulas and detailed collisional-radiative simulations. While the impact on plasma ionization is small, K-shell spectra can be significantly modified. Based on these findings, we demonstrate that K-shell spectroscopy can be used to infer super-Gaussian or other similar non-equilibrium electron distributions.

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H. P. Le, E. V. Marley, H. A. Scott. 2025-07-03. Impact of super-Gaussian electron distributions on plasma K-shell emission. https://doi.org/10.1103/f5x3-j834

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