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arXiv · 1910.12292

Tearing instability in Alfv\'en and kinetic-Alfv\'en turbulence

Stanislav Boldyrev·Nuno F. Loureiro
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Abstract

Recently, it has been realized that magnetic plasma turbulence and magnetic field reconnection are inherently related phenomena. Turbulent fluctuations generate regions of a sheared magnetic field that become unstable to the tearing instability and reconnection, thus modifying turbulence at the corresponding scales. In this contribution, we give a brief discussion of some recent results on tearing-mediated magnetic turbulence. We illustrate the main ideas of this rapidly developing field of study by concentrating on two important examples -- magnetohydrodynamic Alfv\'en turbulence and small-scale kinetic-Alfv\'en turbulence. Due to various potential applications of these phenomena in space physics and astrophysics, we specifically try not to overload the text by heavy analytical derivations, but rather present a qualitative discussion accessible to a non-expert in the theories of turbulence and reconnection.

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Stanislav Boldyrev, Nuno F. Loureiro. 2019-10-27. Tearing instability in Alfv\'en and kinetic-Alfv\'en turbulence. https://doi.org/10.1029/2020ja028185

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