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arXiv · 2312.05494

Electron Weibel instability and~quasi-magnetostatic structures in~an~expanding collisionless plasma

Vladimir Kocharovsky·Anton Nechaev·Mikhail Garasev
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Abstract

We outline transient quasi-magnetostatic phenomena associated with Weibel-type instabilities, mainly, the formation and decay of the current sheets and filaments. We consider a collisionless anisotropic plasma cloud with hot electrons expanding into an inhomogeneous background plasma taking into account an external magnetic field in different geometries entailing (i) a hot-electron spot of a circular or cylindrical form within an initial-value problem or a finite-time injection of electrons from a target surface, (ii) inhomogeneous layers of cold background plasma of different densities and spatial scales, (iii) an external magnetic field with three orientations: perpendicular to the target or along it, directed either across or parallel to a long axis of the hot-electron spot. We heed typical laser-plasma experiments. We outline development of the principle current structures linked with distinct forms of the anisotropic electron velocity distribution using particle-in-cell modeling of the instability process for diverse sets of the attributes (i)--(iii). Applications to the analysis of laboratory and space plasma problems involving an explosive development of the small-scale filamentation of the electric current and self-consistent magnetic turbulence are discussed.

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Vladimir Kocharovsky, Anton Nechaev, Mikhail Garasev. 2023-12-09. Electron Weibel instability and~quasi-magnetostatic structures in~an~expanding collisionless plasma. https://doi.org/10.1007/s41614-024-00157-4

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