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arXiv 1006.2659astro-ph.SR
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Alfvenic turbulence及其平行电场的陀螺流体描述

Gyrofluid description of Alfvenic turbulence and its parallel electric field

N. H. Bian, E. P. Kontar

摘要:

在强背景磁场的存在下,具有$k_{\parallel}/k_{\perp}\ll 1$的各向异性阿尔夫文涨落保持在比离子回旋频率小得多的频率。基于均匀等离子体中电磁回旋流体方程的最简截断,建立了一个由Alfvénic湍流产生的能量级联模型,该模型平滑地连接了大磁流体动力学(MHD)尺度和小“动力学”尺度。作为$k_{\perp}$和$k_{\parallel}$的函数,得到了电磁涨落的标度关系。此外,一个特别的注意是支付的光谱结构的平行电场,这是由Alfvénic湍流产生的。其原因是这种平行电场在湍流加速和粒子传输中的潜在含义。对于电磁湍流,这个问题在[A.长谷川K. Mima,J. Geophys. Res. { \bf 83} 1117(1978)]。

英文摘要:

Anisotropic Alfvénic fluctuations with $k_{\parallel}/k_{\perp}\ll 1$ remain at frequencies much smaller than the ion cyclotron frequency in the presence of a strong background magnetic field. Based on the simplest truncation of the electromagnetic gyrofluid equations in a homogeneous plasma, a model for the energy cascade produced by Alfvénic turbulence is constructed, which smoothly connect the large magnetohydrodynamics (MHD) scales and the small "kinetic" scales. Scaling relations are obtained for the electromagnetic fluctuations, as a function of $k_{\perp}$ and $k_{\parallel}$. Moreover, a particular attention is paid to the spectral structure of the parallel electric field which is produced by Alfvénic turbulence. The reason is the potential implication of this parallel electric field in turbulent acceleration and transport of particles. For electromagnetic turbulence, this issue was raised some time ago in [A. Hasegawa, K. Mima, J. Geophys. Res. {\bf 83} 1117 (1978)].

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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