Effects of Alpha–Proton Differential Flow on Proton Temperature Anisotropy
Effects of Alpha–Proton Differential Flow on Proton Temperature Anisotropy
复制标题
α质子差流对太阳风中质子温度各向异性不稳定性的影响：风观测
DOI：
10.3847/1538-4357/ab3d35
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
A. Zhao
中科院分区：
文献类型：
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作者：
G. Q. Zhao;H. Li;H. Q. Feng;D. J. Wu;H. B. Li;A. Zhao
等离子体动能波和α-质子差分流是太阳风演化研究的两个重要课题。根据2005-2015年的Wind资料，本文报道了质子回旋频率附近的电磁回旋波(ECW)的发生与α-质子差流Vd的方向密切相关。当Vd从反太阳方向旋转到太阳方向时，ECW的出现率和左手(L H)极化ECW的百分比显著下降。特别是，结果表明，在自转过程中，主极化由左旋极化转变为右旋极化。对质子和α粒子参数按Vd方向排序的研究进一步表明，α-质子差流的大动能对应于ECW的高出现率。这些结果与α-质子差流对质子温度影响的理论预测是一致的。
Plasma kinetic waves and alpha–proton differential flow are two important subjects on the topic of solar wind.evolution. Based on the Wind data during 2005–2015, this paper reports that the occurrence of electromagnetic.cyclotron waves (ECWs) near the proton cyclotron frequency significantly depends on the direction of alpha–.proton differential flow Vd. As Vd rotates from the anti-Sunward direction to the Sunward direction, the occurrence.rate of ECWs as well as the percentage of left-handed (LH) polarized ECWs decreases considerably. In particular,.it is shown that the dominant polarization changes from LH polarization to right-handed polarization during the.rotation. The investigation on proton and alpha particle parameters ordered by the direction of Vd further illustrates.that large kinetic energies of alpha–proton differential flow correspond to high occurrence rates of ECWs. These.results are consistent with theoretical predictions for effects of alpha–proton differential flow on proton temperature.anisotropy instabilities.