Alfvén Wave Phase Mixing as a Source of Fast Magnetosonic Waves
Alfvén Wave Phase Mixing as a Source of Fast Magnetosonic Waves
复制标题
阿尔文波相位混合作为快磁声波源
DOI：
10.1023/a:1004965725929
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发表时间：
1997
期刊：
影响因子：
2.8
通讯作者：
K. Murawski
中科院分区：
文献类型：
--
作者：
V. Nakariakov;B. Roberts;K. Murawski
考虑了通过在均匀磁场中密度平滑不均匀的冷等离子体中相混合阿尔文波来非线性激发快磁声波。如果系统最初不存在快波，则非线性会导致阿尔文波中的横向梯度激发快波。介质的不均匀性大大提高了非线性阿尔文-快磁声波耦合的效率。由阿尔文波相位混合永久产生的快波从具有阿尔文速度横向梯度的区域折射。这种非线性过程提出了一种通过激励倾斜传播的快波进行相混合来间接等离子体加热的机制。
The nonlinear excitation of fast magnetosonic waves by phase mixing Alfvén waves in a cold plasma with a smooth inhomogeneity of density across a uniform magnetic field is considered. If initially fast waves are absent from the system, then nonlinearity leads to their excitation by transversal gradients in the Alfvén wave. The efficiency of the nonlinear Alfvén–fast magnetosonic wave coupling is strongly increased by the inhomogeneity of the medium. The fast waves, permanently generated by Alfvén wave phase mixing, are refracted from the region with transversal gradients of the Alfvén speed. This nonlinear process suggests a mechanism of indirect plasma heating by phase mixing through the excitation of obliquely propagating fast waves.