论文标题
使用MMS湍流活动数据直接测量太阳能泰勒微观
Direct Measurement of the Solar-Wind Taylor Microscale using MMS Turbulence Campaign Data
论文作者
论文摘要
使用新型的磁层多尺度（MMS）任务数据在2019 MMS太阳风湍流活动中积累，我们计算了太阳风中湍流磁场的Taylor Microscale $（λ_{\ Mathrm {t}}）$。泰勒微观代表经典湍流理论中耗散过程的开始。但是，从航天器数据中对泰勒量表的准确估计通常由于低时间节奏，时间去相关的影响以及其他因素而困难。先前的报告完全基于泰勒冷冻 - 内近似，该近似结合了时间依赖性，或者使用多个数据集获得的时间依赖性，该数据集引入了血浆参数的样本 - 样本 - 样本变化，或者Spacecraft距离大于本研究。在广告系列期间，与4 mms航天器的对数间距进行线性形成的唯一配置，可以直接评估来自单个数据集的$λ_ {\ mathrm {t}} $，独立于与Taylor Frozen-In近似相关。获得$λ_ {\ Mathrm {t}} \约7000 \，\ Mathrm {km} $的值，比以前的估计大约大3倍。
Using the novel Magnetospheric Multiscale (MMS) mission data accumulated during the 2019 MMS Solar Wind Turbulence Campaign, we calculate the Taylor microscale $(λ_{\mathrm{T}})$ of the turbulent magnetic field in the solar wind. The Taylor microscale represents the onset of dissipative processes in classical turbulence theory. An accurate estimation of Taylor scale from spacecraft data is, however, usually difficult due to low time cadence, the effect of time decorrelation, and other factors. Previous reports were based either entirely on the Taylor frozen-in approximation, which conflates time dependence, or that were obtained using multiple datasets, which introduces sample-to-sample variation of plasma parameters, or where inter-spacecraft distance were larger than the present study. The unique configuration of linear formation with logarithmic spacing of the 4 MMS spacecraft, during the campaign, enables a direct evaluation of the $λ_{\mathrm{T}}$ from a single dataset, independent of the Taylor frozen-in approximation. A value of $λ_{\mathrm{T}} \approx 7000 \, \mathrm{km}$ is obtained, which is about 3 times larger than the previous estimates.
