Observations of the Electromagnetic Electron Kelvin‐Helmholtz Instability and Its Impact on the Dynamics Inside a Flux Rope

The electromagnetic electron Kelvin‐Helmholtz instability (EM EKHI) and its impact on the dynamics inside a flux rope (FR) is investigated through observations from the Magnetospheric Multiscale mission. The convection term dominated electric field drives E× Bdrift in the FR, which supports a strong electron shear flow. The electron shear flow is unstable to the EM EKHI, which results in an electron velocity vortex and many current filaments in the FR. In one of the current filaments, ion and electron demagnetization and strong energy conversion are observed. The continuous radial nulls and obvious reconstructed X‐line topology indicate that magnetic reconnection may occur in this current filament. Magnetic reconnection can release magnetic energy and energize particles. Hence, reconnection is thought to be responsible for many explosive phenomena in space. Flux ropes are generated by reconnection and can affect the reconnection processes in turn. Flux ropes are important places for electron acceleration and energy conversion. However, how these processes happen inside a flux rope is unclear. Using high‐resolution data from the Magnetospheric Multiscale mission, we identify electromagnetic electron Kelvin‐Helmholtz instability inside a flux rope, which induces an electron velocity vortex and breaks the compact current sheet in the flux rope into many current filaments. A current filament with strong energy conversion is found near the electron velocity vortex. Ions and electrons demagnetization, radial nulls, and reconstructed X‐line topology are found inside this current filament, implying that the current filament may be reconnecting. Our observations reveal the complex evolution of a flux rope, which can help to understand the dynamics of flux ropes and the roles of flux ropes playing in the magnetotail. The electromagnetic electron Kelvin‐Helmholtz instability (EM EKHI) is identified in a flux ropeThe EM EKHI induces an electron velocity vortex and many small‐scale current filaments in the flux ropeA current filament with strong energy conversion, where reconnection may happen, is found near the electron velocity vortex The electromagnetic electron Kelvin‐Helmholtz instability (EM EKHI) is identified in a flux rope The EM EKHI induces an electron velocity vortex and many small‐scale current filaments in the flux rope A current filament with strong energy conversion, where reconnection may happen, is found near the electron velocity vortex