阶段空间级和随机加热的不可逆性在几乎无碰撞的等离子体流中
Michael L Nastac1,2,3, Robert J Ewart1,4, Wrick Sengupta5,6
1Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.
Physical review. E
|July 18, 2024
概括
这项研究揭示了随机电场如何驱动流扩散,并在等离子体中产生细微结构. 这个过程,一个相空间级联,导致不可逆转的随机加热和有效的粒子能量消耗.
科学领域:
- 等离子体物理学的物理学
- 运动理论 运动理论
- 统计力学 统计力学
背景情况:
- 无碰撞等离子体在外力下表现出复杂的动态.
- 随机电场诱导粒子系统中的流扩散和加热.
- 了解能量级联和消散对于等离子体行为至关重要.
研究的目的:
- 在几乎没有碰撞的等离子体中分析克莱赫南模型的动力类比.
- 描述阶段空间中微尺度结构的生成和转移.
- 为了研究无碰撞不变量 (C2) 作为负类比的作用.
主要方法:
- 用测试粒子建模一个1D空间和1D速度等离子体.
- 强加一个外部驱动的随机电场.
- 在里埃空间中计算稳态流和无碰撞不变量 (C2) 的光谱.
主要成果:
- 一个相位布将C2从大尺度转移到小尺度的位置和速度.
- 非线性导致异常扩散和k空间中的分数拉普拉斯运算子.
- 级联加速能量消散,使得随机加热不可逆转.
结论:
- 布有效地将C2转移到高空间 (k) 和速度 (s) 波数.
- 线性和非线性时间尺度之间的关键平衡支配了布.
- 与线性系统相比,非线性效应增强相位混合和粒子能量消散.
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