Parker Solar Probe (PSP) observed a large variety of Alfvénic fluctuations in the fast and slow solar wind flow during its two perihelia. The properties of Alfvénic solar wind turbulence have been studied for decades in the near-Earth environment. A spectral index of −5/3 or −2 for magnetic field fluctuations has been observed using spacecraft measurements, which can be explained by turbulence theories of nearly incompressible magnetohydrodynamics (NI MHD) or critical balance. In this study, a rigorous search of field-aligned solar wind is applied to PSP measurements for the first time, which yields two events in the apparently slow solar wind. The parallel spectra of the magnetic fluctuations in the inertial range show a ##IMG## [http://ej.iop.org/images/0004-637X/898/2/113/apjab9b7eieqn1.gif] {${k}_{\parallel }^{-5/3}$} power law. Probability distributions of the magnetic field show that these events are not contaminated by intermittent structures, which,...

中文翻译：

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从派克太阳探测器观测到的场对准太阳风湍流的光谱特征

派克太阳探测器（PSP）在其两个近日点期间观察到快速和慢速太阳风中的阿尔弗维奇起伏很大。在近地环境中研究Alfvénic太阳风湍流的特性已有数十​​年的历史了。使用航天器测量已经观察到磁场波动的光谱指数为-5/3或-2，这可以用几乎不可压缩的磁流体动力学（NI MHD）或临界平衡的湍流理论来解释。在这项研究中，首次将严格对准场的太阳风用于PSP测量，这在明显慢的太阳风中产生了两个事件。惯性范围内的电磁涨落的平行光谱显示为## IMG ## [http://ej.iop.org/images/0004-637X/898/2/113/apjab9b7eieqn1.gif] {$ {k} _ {\ parallel} ^ {-5/3} $}幂定律。