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在空气中通过低强度激光脉冲列车产生rf辐射
Gavin Blair1,2, Phillip Sprangle1,2
1Department of Physics, University of Maryland, College Park, Maryland 20742, USA.
Physical review. E
|August 16, 2023
概括
低强度激光脉冲列车通过电离空气和驱动等离子振荡产生定向射频 (rf) 辐射. 背景放射性对于启动这种激光诱导的等离子体辐射机制至关重要.
科学领域:
- 血物理学的等离子体物理学
- 激光与物质的相互作用
- 电磁辐射的产生电磁辐射的产生.
背景情况:
- 低强度激光脉冲列车 (LPT) 可以电离空气,形成等离子丝.
- 背景放射能在启动电离级联过程中起着关键作用.
研究的目的:
- 分析和数值模拟由LPTs在空气中产生定向射频 (rf) 辐射的机制.
- 调查背景放射能在启动等离子体形成和随后的rf发射中的作用.
主要方法:
- 使用含有光离子化,碰撞离子化和权衡运动力的流体方程进行数值模拟.
- 建模背景放射能对种子电子生成的影响.
- 对等离子体振荡和由此产生的rf辐射频谱的分析.
主要成果:
- 低于道电离水平的LPT可以产生定向的rf辐射.
- 由重力驱动力驱动的辐射等离子体振荡导致电子电流和rf发射.
- 等离子体密度的增加可以使LPT失焦,限制相互作用长度;rf频谱包括基本频率和波.
结论:
- 这项研究提出了通过空气中的激光诱导等离子体产生rf辐射的综合模型.
- 数字模拟与特定参数的实验数据保持一致,验证了拟议的机制.
- 背景放射性对于启动低强度LPT驱动的RF产生过程至关重要.
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