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arXiv · 2508.02519

Influence of finite ion Larmor radius on the dynamics of weakly-collisional plasma jets colliding in magnetic arch

Artem V. Korzhimanov·Roman S. Zemskov·Sergey A. Koryagin·Mikhail E. Viktorov
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Abstract

The effect of the finite ion Larmor radius on the dynamics of two counterstreaming weakly collisional plasma flows in a magnetic field of an arch configuration is considered. Hybrid numerical simulations show that in a system whose dimensions are close to the ion Larmor radius, more intense interaction dynamics are observed, the magnetic arch experiences a significant expansion with the formation of a region with an irregular character of magnetic lines, in which magnetic reconnection processes occur. In this case, the generation of a surface wave of the ion-cyclotron range is observed at the boundaries of the arch. An increase in the scale of the system compared to the ion Larmor radius leads to a transition to the ideal MHD regime, in which the evolution of the arch occurs much more slowly, and the development of instabilities is not observed.

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Artem V. Korzhimanov, Roman S. Zemskov, Sergey A. Koryagin, Mikhail E. Viktorov. 2025-08-04. Influence of finite ion Larmor radius on the dynamics of weakly-collisional plasma jets colliding in magnetic arch. https://doi.org/10.1017/s0022377825101128

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