Numerical Study of Oscillatory Magnetic Reconnection in Laboratory Plasma Driven by Alternating Currents
Researchers used the open-source MPI-AMRVAC framework to simulate oscillatory magnetic reconnection in a laboratory plasma driven by alternating currents, finding that a magnetic null region collapses to form current sheets that shift orientation over time. The study examined how the Hall effect, thermal pressure, and out-of-plane current density evolve during this process, and how varying current amplitude affects these quantities. Understanding oscillatory reconnection has implications for both laboratory plasma physics and solar/space physics phenomena.
A numerical study accepted for publication in Physics of Plasmas investigates oscillatory magnetic reconnection in a laboratory plasma setting, using the open-source MPI-AMRVAC magnetohydrodynamics framework. The simulations show that when a magnetic null is perturbed by incoming fast magnetoacoustic waves driven by an alternating current, the null region collapses to initially form a y-directed current sheet, which subsequently reorients to the x-direction. The x-directed current sheet exhibits lower enhanced thermal pressure and out-of-plane current density compared to the y-directed sheet. The Hall effect generates an out-of-plane plasma flow that lags behind the peaks in thermal pressure and out-of-plane current density. Increasing the amplitude of the alternating current amplifies thermal pressure, out-of-plane current density, and plasma flow, while also causing the first peaks of thermal pressure and current density to occur earlier in time.
What's missing
The study is purely numerical; no experimental laboratory validation of the simulation results is presented.
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- arXiv physicsCenter
A Numerical Experiment on Oscillatory Magnetic Reconnection in a Laboratory Plasma System Driven by Alternating Currents
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