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arXiv · 1512.03628

Energy dissipation processes in solar wind turbulence

Y. Wang·F. S. Wei·X. S. Feng·X. J. Xu·J. Zhang·T. R. Sun·P. B. Zuo
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Abstract

Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation cannot be ultimately achieved without collisions, and so how turbulent kinetic energy is dissipated in the nearly collisionless solar wind is a challenging problem. Wave particle interactions and magnetic reconnection are two possible dissipation mechanisms, but which mechanism dominates is still a controversial topic. Here we analyze the dissipation region scaling around a solar wind magnetic reconnection region. We find that the magnetic reconnection region shows a unique multifractal scaling in the dissipation range, while the ambient solar wind turbulence reveals a monofractal dissipation process for most of the time. These results provide the first observational evidences for the intermittent multifractal dissipation region scaling around a magnetic reconnection site, and they also have significant implications for the fundamental energy dissipation process.

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Y. Wang, F. S. Wei, X. S. Feng, X. J. Xu, J. Zhang, T. R. Sun, P. B. Zuo. 2015-12-31. Energy dissipation processes in solar wind turbulence. https://doi.org/10.1088/0067-0049%2F221%2F2%2F34

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