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arXiv · 2409.13991

Observation of Chaotic fluctuations in Turbulent Plasma

Riddi Bandyopadhyay·Nicolas V. Sarlis·James M. Weygand·Robert J. Strangeway·Roy B. Torbert·James L. Burch
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Abstract

Turbulence is a prevalent phenomenon in space and astrophysical plasmas, often characterized by stochastic fluctuations. While laboratory experiments and numerical simulations have revealed chaotic behavior, in-situ observations of turbulent plasmas in natural environments have predominantly shown highly stochastic signatures. Here, we present unprecedented in-situ evidence of chaotic fluctuations in the turbulent solar wind plasma downstream of the Earth's bow shock. By analyzing the relative location of magnetic-field fluctuations on the permutation entropy-complexity plane (C-H plane), we demonstrate that turbulence in the magnetosheath plasma exhibits characteristics of chaotic fluctuations rather than stochastic behavior, diverging from the expected traits of well-developed turbulence. This finding challenges established notions of plasma turbulence and reveals the need for caution when using the magnetosheath as a laboratory for studying plasma turbulence.

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Riddi Bandyopadhyay, Nicolas V. Sarlis, James M. Weygand, Robert J. Strangeway, Roy B. Torbert, James L. Burch. 2024-09-21. Observation of Chaotic fluctuations in Turbulent Plasma. https://arxiv.org/abs/2409.13991

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