Force‐Free Current Sheets in the Jovian Magnetodisk: The Key Role of Electron Field‐Aligned Anisotropy

Current sheets are an essential element of the planetary magnetotails, where strong plasma currents self‐consistently support magnetic field gradients. The current sheet configuration is determined by plasma populations that contribute to the current density. The most commonly investigated configuration is supported by diamagnetic cross‐field currents of hot ions, typical for the magnetospheres of magnetized planets. In this study, we examine a new type of the current sheet configuration supported by field‐aligned currents from electron streams in the Jovian magnetodisk. Such bi‐directional streams increase the electron thermal anisotropy close to the fire‐hose instability threshold and lead to strong magnetic field shear. The current sheet configuration supported by electron streams is nearly force‐free, with |B| ≈ const across the sheet. Using Juno plasma and magnetic field measurements, we investigate the internal structure of such current sheets and discuss possible mechanisms for their formation.

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