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arXiv · 2504.19202

Explosive growth of large-scale magnetic fluctuations due to particle scattering on developed small-scale Weibel turbulence in magnetoactive plasma

N. A. Emelyanov·Vl. V. Kocharovsky
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Abstract

The analytical theory of non-linear generation of large-scale magnetic turbulence in anisotropic magnetoactive plasma in the quasilinear approximation without taking into account the direct non-linear interaction of individual harmonics is constructed. It is shown that anomalous collisions of particles due to scattering on small-scale fluctuations of the developed Weibel turbulence lead to instability of long-wave harmonics, which are stable in the linear approximation. The non-linear growth of such harmonics at a given anisotropy of the particle velocity distribution, consistent with the dynamics of short-wave perturbations at the saturation stage and possible anisotropic particle injection, occurs in the superexponential regime and corresponds to an explosive-type instability. The growth law of the large-scale magnetic field is found analytically and the critical time of explosive instability is estimated.

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N. A. Emelyanov, Vl. V. Kocharovsky. 2025-04-27. Explosive growth of large-scale magnetic fluctuations due to particle scattering on developed small-scale Weibel turbulence in magnetoactive plasma. https://arxiv.org/abs/2504.19202

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