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arXiv · 2507.00777

Relaxation of a Two Electron-Temperature Relativistic Hot Electron-Positron-Ion Plasma

Abstract

The relaxation of a relativistic hot electron-positron plasma with a small fraction of cold electrons and ion species is investigated, and a quadruple Beltrami (QB) relaxed state is derived. The QB state is a non-force-free state that is a linear combination of four single force-free states and is therefore comprised of four self-organized structures. Additionally, triple as well as double Beltrami states can be obtained by adjusting the generalized helicities of plasma species. The analysis of the relaxed states demonstrates that, for specific values of the generalized helicities, cold species density and relativistic temperature can transform paramagnetic structures into diamagnetic structures and vice versa. Also, when the flow vortices of plasma species are aligned with the magnetic field, it leads to a classically perfect diamagnetic relaxed state, and the strength of the magnetic field increases with a decrease in relativistic temperature and an increase in cold species density. The current investigation aims to enhance comprehension of energy transformation mechanisms and the formation of multiscale structures in astrophysical and laboratory plasmas.

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Usman Shazad, M. Iqbal. 2025-07-01. Relaxation of a Two Electron-Temperature Relativistic Hot Electron-Positron-Ion Plasma. https://doi.org/10.1007/s13538-023-01393-8

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