Title: Interplanetary magnetic correlation and low-frequency spectrum over many solar rotations Show Chinese title

Title: 行星际磁场相关性和多个太阳旋转的低频谱

Abstract: Fluctuations and structure across a wide range of spatial and temporal scales are frequently studied in the solar wind. The properties of the low-frequency fluctuations are of relevance to turbulent energy injection into the plasma and the transport of high-energy cosmic rays. Correlation analysis of decade-long intervals of interplanetary data permits study of fluctuations at time scales much longer than suitably defined correlation times, and therefore at frequencies well below those associated with the Kolmogorov inertial range of in situ turbulence. At the frequencies of interest, we study the familiar occurrence of the 1/f spectral signature. We also study point spectral features due to solar rotation and their relation with the 1/f signal. We report novel properties at timescales ranging from minutes up to years, using data selected by wind speed, phase of solar cycle, and cartesian components of the magnetic field. A surprising finding is that the power in solar rotation harmonics is consistent with an extension of the 1/f spectrum, down to frequencies as low as around 5e-7 Hz. The presence of a broadband 1/f spectrum across different wind types supports the interpretation that 1/f signals may be related to or even originate from the solar dynamo. Show Chinese abstract

Abstract: 在太阳风中，广泛的空间和时间尺度上的波动和结构经常被研究。 低频波动的特性与等离子体中的湍流能量注入以及高能宇宙射线的传输有关。 对十年期的行星际数据进行相关分析，允许研究比适当定义的相关时间长得多的时间尺度上的波动，因此是在低于原位湍流科莫戈罗夫惯性范围相关频率的范围内进行研究。 在感兴趣的频率下，我们研究了熟悉的1/f谱特征。 我们还研究了由于太阳自转产生的点谱特征及其与1/f信号的关系。 我们报告了从几分钟到几年的时间尺度上的新特性，使用根据风速、太阳周期相位和磁场的笛卡尔分量选择的数据。 一个令人惊讶的发现是，太阳自转谐波中的功率与1/f谱的延伸一致，低至约5e-7 Hz的频率。 在不同风型中存在宽带1/f谱，支持1/f信号可能与太阳发电机有关甚至起源于太阳发电机的解释。