激光等离子体的热导率
Nathaniel R Shaffer1, Andrei V Maximov1,2, Valeri N Goncharov1,2
1Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
Physical review. E
|November 18, 2023
概括
激光在等离子体中的吸收通过改变电子分布,显著降低了电子的导热率. 这种对等离子体建模至关重要的效应,通过依赖激光强度和波长的新参数来量化.
科学领域:
- 等离子体物理学的物理学
- 激光与等离子体相互作用
- 计算物理 计算物理
背景情况:
- 电子热导率是模拟激光制造的等离子体的一个关键参数.
- 激光吸收可以显著改变等离子体的特性,偏离理想的平衡状态.
研究的目的:
- 开发并介绍激光制造的等离子体中电子热导率的模型.
- 研究激光吸收对电子分布和导电性的影响.
主要方法:
- 使用Vlasov-Fokker-Planck模拟来模拟等离子体行为.
- 根据模拟结果开发了分析匹配.
主要成果:
- 激光吸收驱动电子从麦克斯韦-博尔兹曼平衡,耗尽大量和尾部种群.
- 电子分布被发现接近超高斯形式,指数取决于激光参数 (强度,波长) 通过α=Zv_{E}^{2}/v_{T}^{2}.
- 由于尾部电子耗尽,对于α=0.5观察到导热率降低到其零强度值的一半.
结论:
- 呈现的模型准确地捕捉了由于激光吸收而导致的电子导热率的减少.
- 分析适合提供了一个实用的工具,用于纳入辐射-水力学代码.
- 这些发现可以在等离子体模拟中对非局部导电模型的局部极限进行校正.
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