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arXiv · 2507.17621

Cross-helicity and chaotic dynamics of full-disc solar magnetic field

A. Bershadskii
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Abstract

Using the results of laboratory experiments and direct numerical simulations, as well as observations of the full-disc solar magnetic field and sunspot number dynamics, it is demonstrated that cross-helicity can dominate the decaying part of the frequency power spectra of the magnetic field generated by a magnetohydrodynamic (MHD) dynamo in chaotic/turbulent swirling flows for sufficiently strong MHD turbulence (including the solar dynamo). The theoretical consideration is based on a Kolmogorov-like phenomenology within the framework of the distributed chaos concept. It is also shown that the solar full-disc magnetic field for the last two solar cycles with weak magnetic activity exhibits deterministic chaotic behavior concentrated around the equator.

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A. Bershadskii. 2026-09-22. Cross-helicity and chaotic dynamics of full-disc solar magnetic field. https://arxiv.org/abs/2507.17621

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