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异常电阻和电子加热由较低的混合漂流波在磁再连接与指导场的磁场连接期间

Jongsoo Yoo¹, Jonathan Ng², Hantao Ji^1,3

¹Princeton Plasma Physics Laboratory, Princeton, New Jersey 08542, USA.

Physical review letters

|April 19, 2024

概括

低混合漂移波 (LHDW) 在磁再连接中引起显著异常电阻和电子加热.

科学领域:

血物理学的等离子体物理学
天体物理学天体物理学
太空物理空间物理学

背景情况:

磁重新连接是等离子体物理学中的一个基本过程,对于太阳耀斑和极光等现象至关重要.
扩散区域内的异常电阻和电子加热是理解重新连接动态的关键.
低混合漂移波 (LHDW) 已被理论化为在这些过程中发挥作用.

研究的目的:

在实验室磁再连接层中研究准静电LHDW (ES-LHDW) 的激发和影响.
量化ES-LHDW产生的异常电阻和电子加热.
确定波粒子相互作用在磁再连接中的作用.

主要方法:

实验室实验模拟磁再连接与有限的引导场.
测量密度波动 (δn_{e}) 和外平面电场波动 (δE_{Y}).
验证线性关系和准线性分析,以估计异常电阻和电子加热.

主要成果:

在电子扩散区域观察到ES-LHDW,表现出很大的密度和电场波动.
由于ES-LHDW的异常电阻被发现是经典电阻的两倍,占平均重新连接电场的20%.
异常的电子加热 (2.6±0.3 MW/m3) 超过了经典的欧米加热 (2.0±0.2 MW/m3),与波幅相关.

结论:

ES-LHDW是磁再连接层中异常电阻和电子加热的重要来源.
波粒子相互作用,特别是由LHDW驱动,对于重新连接期间的能量消散和粒子加热至关重要.
这些发现直接证明了LHDW在实验室和潜在的天体物理再连接事件中的重要性.

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