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arXiv · 2505.24607

Resonance density range governs two-plasmon decay saturation and enables hot-electron prediction in inertial confinement fusion

C. Yao·J. Li·L. Hao·R. Yan·T. Tao·G-N. Zheng·Q. Jia·Y-K. Ding·J. Zheng
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Abstract

The saturation level of parametric instabilities critically determines their impact on fusion plasmas. We identify the resonance density range of two-plasmon decay as the critical parameter governing nonlinear saturation of ion density fluctuations and Langmuir waves, which drive hot-electron generation. Using this insight, we develop a predictive scaling model for the hot-electron energy fraction f_{hot} that depends only on the laser intensity I, with plasma conditions encoded via plasma ablation theory. The model can work for various experimental configurations-requiring only two (I, f_{hot}) data points to calibrate coefficients-and successfully reproduces results from prior OMEGA and OMEGA-EP experiments.

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C. Yao, J. Li, L. Hao, R. Yan, T. Tao, G-N. Zheng, Q. Jia, Y-K. Ding, J. Zheng. 2025-05-30. Resonance density range governs two-plasmon decay saturation and enables hot-electron prediction in inertial confinement fusion. https://arxiv.org/abs/2505.24607

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