Excitation of the lower-hybrid drift instability in the outflow of electron-only magnetic reconnection

B. K. Russell; K. Sakai; Y. Zhang; L. Gao; E. G. Blackman; W. Daughton; C. Dong; J. Katz; S. R. Klein; C. C. Kuranz; X. Li; X. M. Li; A. L. Milder; J. Ng; K. Orr; G. Pomraning; J. P. Schell; A. Stanier; J. Yoo; H. Ji

arXiv · 2608.20299

Excitation of the lower-hybrid drift instability in the outflow of electron-only magnetic reconnection

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Abstract

We report experimental evidence for the lower-hybrid drift instability in the current sheet normal direction of electron-only magnetic reconnection. In our laser-driven capacitor-coil experiment, the system size ($\sim$3 ion skin depths) places it in the electron-only regime. Yet, Thomson scattering reveals out-of-plane electron drift oscillations at the local lower-hybrid frequency, with kinetic energy density reaching $\sim$18% of the local magnetic energy density. Linear theory with the measured parameters predicts more than ten e-folding times of growth, indicating that the instability reaches the nonlinear regime within the measurement window. Supported by particle-in-cell simulations, these results demonstrate the importance of ions in the dissipation and energy transfer in electron-only reconnection where their significance has not been previously recognized.

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B. K. Russell, K. Sakai, Y. Zhang, L. Gao, E. G. Blackman, W. Daughton, C. Dong, J. Katz, S. R. Klein, C. C. Kuranz, X. Li, X. M. Li, A. L. Milder, J. Ng, K. Orr, G. Pomraning, J. P. Schell, A. Stanier, J. Yoo, H. Ji. 2026-08-20. Excitation of the lower-hybrid drift instability in the outflow of electron-only magnetic reconnection. https://arxiv.org/abs/2608.20299

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