THE EFFECT OF ELECTRON THERMAL PRESSURE ON THE OBSERVED MAGNETIC HELICITY IN THE SOLAR WIND
THE EFFECT OF ELECTRON THERMAL PRESSURE ON THE OBSERVED MAGNETIC HELICITY IN THE SOLAR WIND
复制标题
电子热压对观测到的太阳风磁螺旋度的影响
DOI：
10.3847/1538-4357/833/2/212
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Charles W. Smith
中科院分区：
文献类型：
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作者：
S. Markovskii;B. Vasquez;Charles W. Smith
对1Au太阳风磁螺旋度谱进行了统计分析。使用了由Wind航天器的磁场和等离子体数据汇编而成的太阳风间隔的大型数据库。研究了电子热压对螺旋度特征波数位置，即谱峰位置的影响。该位置显示出对电子和质子压强的统计上的显著依赖性。然而，当这两种压力加在一起时，依赖性最强。这些发现证实，在较小的动力学尺度上，磁螺旋度的产生与湍流涨落的可压缩性增加有关。有观点认为，仪器伪影对螺旋度特征没有贡献。
Statistical analysis of magnetic helicity spectra in the solar wind at 1 au is carried out. A large database of the solar wind intervals assembled from Wind spacecraft magnetic and plasma data is used. The effect of the electron thermal pressure on the wavenumber position of the helicity signature, i.e., the peak of the spectrum, is studied. The position shows a statistically significant dependence on both the electron and proton pressures. However, the strongest dependence is seen when the two pressures are summed. These findings confirm that the generation of the magnetic helicity is associated with an increasing compressibility of the turbulent fluctuations at smaller kinetic scales. It is argued that instrumental artifacts do not contribute to the helicity signature.