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arXiv · 2001.04869

Electron-only reconnection in kinetic Alfv\'en turbulence

Cristian Vega·Vadim Roytershteyn·Gian Luca Delzanno·Stanislav Boldyrev
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Abstract

We study numerically small-scale reconnection events in kinetic, low-frequency, quasi-2D turbulence (termed kinetic-Alfv\'en turbulence). Using 2D particle-in-cell simulations, we demonstrate that such turbulence generates reconnection structures where the electron dynamics do not couple to the ions, similarly to the electron-only reconnection events recently detected in the Earth's magnetosheath by Phan et al. (2018). Electron-only reconnection is thus an inherent property of kinetic-Alfv\'en turbulence, where the electron current sheets have limited anisotropy and, as a result, their sizes are smaller than the ion inertial scale. The reconnection rate of such electron-only events is found to be close to $0.1$.

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Cristian Vega, Vadim Roytershteyn, Gian Luca Delzanno, Stanislav Boldyrev. 2020-01-14. Electron-only reconnection in kinetic Alfv\'en turbulence. https://doi.org/10.3847/2041-8213/ab7eba

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