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arXiv · 1801.01771

Observational evidence for self-generation of small-scale magnetic flux ropes from intermittent solar wind turbulence

Jinlei Zheng·Qiang Hu
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Abstract

We present unique {and additional} observational evidence for the self-generation of small-scale coherent magnetic flux rope structures in the solar wind. Such structures with durations between 9 and 361 minutes are identified from Wind in-situ spacecraft measurements through the Grad-Shafranov (GS) reconstruction approach. The event occurrence counts are on the order of 3,500 per year on average and have a clear solar cycle dependence. We build a database of small-scale magnetic flux ropes from twenty-year worth of Wind spacecraft data. We show a power-law distribution of the wall-to-wall time corresponding well to the inertial range turbulence, which agrees with relevant observations and numerical simulation results. We also provide the axial current density distribution from the GS-based observational analysis, which yields a non-Gaussian probability density function consistent with numerical simulation results.

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Jinlei Zheng, Qiang Hu. 2018-01-05. Observational evidence for self-generation of small-scale magnetic flux ropes from intermittent solar wind turbulence. https://doi.org/10.3847/2041-8213/aaa3d7

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