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arXiv · 2507.00760

Impact of temperature asymmetry and small fraction of static positive ions on the relaxed states of a relativistic hot pair plasma

Abstract

The relaxed state of a magnetized relativistic hot plasma composed of inertial electrons and positrons having different relativistic temperatures and a fraction of static positive ions is studied. From the steady-state solutions of vortex dynamics equations and the relation for current density, a non-force-free triple Beltrami (TB) relaxed state equation is derived. The TB state is characterized by three scale parameters that consequently provide three different self-organized structures. The analysis of the relaxed state shows that for specific values of generalized helicities, the disparity in relativistic temperature and the existence of a small fraction of static positive ions in pair plasma can transform the nature of scale parameters. Moreover, an analytical solution of the TB state for an axisymmetric cylindrical geometry with an internal conductor configuration demonstrates that due to asymmetries of temperature and density of plasma species, diamagnetic structures can transform into paramagnetic ones and vice versa. The present study will improve our understanding of pair plasmas in trap-based plasma confinement experiments and astrophysical environments.

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Usman Shazad, M. Iqbal. 2025-07-01. Impact of temperature asymmetry and small fraction of static positive ions on the relaxed states of a relativistic hot pair plasma. https://doi.org/10.1515/zna-2023-0112

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