Some Properties of the Solar Wind Turbulence at 1 AU Statistically Examined in the Different Types of Solar Wind Plasma
Some Properties of the Solar Wind Turbulence at 1 AU Statistically Examined in the Different Types of Solar Wind Plasma
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DOI：
10.1029/2019ja026580
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发表时间：
2019-04-01
影响因子：
2.8
通讯作者：
Smith, Charles W.
中科院分区：
文献类型：
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作者：
Borovsky, Joseph E.;Denton, Michael H.;Smith, Charles W.
采用四等离子体分类方案将ACE太阳风数据集分为四种类型的等离子体：（1）冕洞起源等离子体，（2）流光带起源等离子体，（3）扇区反转区等离子体和（4）喷射物。利用ACE磁场和等离子体测量数据，分析了1998-2008年四种等离子体在1 Au处太阳风涨落的统计特性。在四种类型的太阳风等离子体之间，（a）轨迹-B，（B）轨迹-v，（c）总能量，（d）磁场强度和（e）等离子体数密度的光谱指数存在细微的统计差异。在这四种等离子体中，（a）Elsasser内向和外向谱指数，（B）外向不平衡，（c）Alfvenicity，（d）归一化矢量-B，矢量-v，磁场强度和数密度起伏幅度，（e）强电流片的总体，（f）突然速度剪切的总体，（g）磁场和速度涨落的各向异性;（h）平行于B的磁场涨落谱指数。有人认为，对于太阳风湍流和波动的研究，四等离子体分类方案优于慢与快分类方案的上级。
A four-plasma classification scheme is used to categorize the ACE solar wind data set into four types of plasma: (1) coronal-hole-origin plasma, (2) streamer-belt-origin plasma, (3) sector-reversal-region plasma, and (4) ejecta. The statistical properties of the solar wind fluctuations at 1 AU are analyzed for each of the four types of plasma in the years 1998-2008 using ACE magnetic field and plasma measurements. Between the four types of solar wind plasma there are subtle statistical differences in the spectral indices of (a) trace-B, (b) trace-v, (c) total energy, (d) magnetic intensity, and (e) plasma number density. Between the four types of plasma there are significant statistical differences (a) in the Elsasser inward and outward spectral indices, (b) in the outward imbalance, (c) in the Alfvenicity, (d) in the normalized vector-B, vector-v, magnetic intensity, and number density fluctuation amplitudes, (e) in the population of strong current sheets, (f) in the population of sudden velocity shears, (g) in the anisotropies of magnetic field and velocity fluctuations, and (h) in the parallel-to-B magnetic field fluctuation spectral index. It is argued that the four-plasma categorization scheme is superior to a slow-versus-fast categorization for the study of turbulence and fluctuations in the solar wind.