Parallel electric fields in nonlinear magnetosonic waves
Parallel electric fields in nonlinear magnetosonic waves
复制标题
非线性磁声波中的平行电场
DOI：
10.1063/1.2806344
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发表时间：
2007
影响因子：
2.2
通讯作者：
Y. Ohsawa
中科院分区：
文献类型：
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作者：
Seiichi Takahashi;Y. Ohsawa
对非线性磁声波中平行于磁场的电场E‖进行了理论和数值研究。采用传统的约简摄动法计算E‖时，将磁压相关项消去，E‖与电子温度Te成正比。假设波幅在（me∕mi）1∕2< λ <1范围内，用一个改进的扰动格式，得到了E‖与冷等离子体中的磁压成正比的表达式。其沿磁场积分F=−∫E‖ds与ϵ2mivA2成正比。一维、全动力学、电磁粒子模拟验证了小振幅波的理论预测。此外，他们证明了eF在大振幅[ε ~ O(1)]斜激波中变成了ε （mivA2+ΓeTe）的数量级。这些理论和模拟表明，磁声波中的E‖在强磁场中可以很强。
The electric field parallel to the magnetic field, E‖, in nonlinear magnetosonic waves is studied theoretically and numerically. In the calculation of E‖ based on the conventional reductive perturbation method, the terms related to the magnetic pressure cancel, and E‖ is proportional to the electron temperature Te. With a modified perturbation scheme assuming that the wave amplitude is in the range (me∕mi)1∕2<ϵ<1, an expression for E‖ is obtained that is proportional to the magnetic pressure in a cold plasma. Its integral along the magnetic field, F=−∫E‖ds, is proportional to ϵ2mivA2. One-dimensional, fully kinetic, electromagnetic particle simulations verify the theoretical predictions for small-amplitude waves. Further, they demonstrate that eF becomes of the order of ϵ(mivA2+ΓeTe) in large-amplitude [ϵ∼O(1)] oblique shock waves. These theory and simulations indicate that E‖ in magnetosonic waves can be strong in a strong magnetic field.
DOI：
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发表时间：
2005
期刊：
Physics of Plasmas 12(8)
影响因子：
--
作者：
Hiroki Hasegawa;Ken Kato;Yukiharu Ohsawa
通讯作者：
Yukiharu Ohsawa