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arXiv · 2410.06391

Systematic 2.5 D resistive MHD simulations with ambipolar diffusion and Hall effect for fast magnetic reconnection

Gabriela Landinez·Fabio D. Lora-Clavijo
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Abstract

In this work, we explore the possibility of the Hall effect and ambipolar diffusion as a mechanism for fast reconnection. The reconnected flux of our resistive and resistive+Hall simulations replicates the GEM results. Furthermore, we investigate, for the first time, the effect of ambipolar diffusion in the GEM. The reconnected flux of the resistive+ambipolar and resistive+Hall+ambipolar simulations showed increases of up to 75\% and 143\%, respectively, compared to the resistive and resistive+Hall simulations, showing that ambipolar diffusion contributes significantly to the reconnected flux. Our second scenario has a magnetic Harris field without perturbations but with an out-of-plane component, known as a guide field. We found that the reconnection rate increased faster with ambipolar diffusion, reaching values close to 0.1 for the resistive+Hall+ambipolar simulation followed by the resistive+Hall. These two simulations achieved the highest kinetic energy, implying more efficient energy conversion during reconnection.

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Gabriela Landinez, Fabio D. Lora-Clavijo. 2024-10-08. Systematic 2.5 D resistive MHD simulations with ambipolar diffusion and Hall effect for fast magnetic reconnection. https://doi.org/10.1016/j.physleta.2024.129897

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