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arXiv · 2306.10435

Kinetic equilibria of relativistic collisionless plasmas in the presence of non-stationary electromagnetic fields

Claudio Cremaschini·Massimo Tessarotto·Zdeněk Stuchlík
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Abstract

The kinetic description of relativistic plasmas in the presence of time-varying and spatially non-uniform electromagnetic fields is a fundamental theoretical issue both in astrophysics and plasma physics. This refers, in particular, to the treatment of collisionless and strongly-magnetized plasmas in the presence of intense radiation sources. In this paper the problem is investigated in the framework of a covariant gyrokinetic treatment for Vlasov-Maxwell equilibria. The existence of a new class of kinetic equilibria is pointed out, which occur for spatially-symmetric systems. These equilibria are shown to exist in the presence of non-uniform background EM fields and curved space-time. In the non-relativistic limit this feature permits the determination of kinetic equilibria even for plasmas in which particle energy is not conserved due to the occurrence of explicitly time-dependent EM fields. Finally, absolute stability criteria are established which apply in the case of infinitesimal symmetric perturbations that can be either externally or internally produced.

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Claudio Cremaschini, Massimo Tessarotto, Zdeněk Stuchlík. 2023-06-17. Kinetic equilibria of relativistic collisionless plasmas in the presence of non-stationary electromagnetic fields. https://doi.org/10.1063/1.4868238

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