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arXiv · 2407.01858

Energetic Ion Composition as a Means of Investigating the Physical Origins of Alpha Particle Heavy Magnetic Switchbacks

Abstract

Magnetic switchbacks are of continuing interest to the scientific community due to the fact that the phenomenon has not been completely understood. Although most of the research into them in the Parker Solar Probe era has largely focused on creating a theoretical framework for causing the field reversal through magnetic interchange reconnection, reconnecting streams of plasma in the solar wind, or shear driven turbulence, it remains unclear to what extent these models may or may not represent the underlying physical reality of magnetic switchbacks. In this paper, we present the results of our study on the energetic ion composition of magnetic switchback events using statistical methods with the aim of obtaining new insights into the underlying physics. In doing so, we find consistent differences in arrival times of the peak flux of different energetic ion species in magnetic switchbacks which are indicative of switchback formed remotely in the solar corona and propagated outwards in the solar wind. We also find that while the data does not directly contradict a linear interchange reconnection model nor the flux rope driven interchange reconnection model, the structure of the plasma within the switchbacks themselves is reminiscent of reconnection produced plasmoids.

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Emily McDougall, Bala Poduval. 2025-09-01. Energetic Ion Composition as a Means of Investigating the Physical Origins of Alpha Particle Heavy Magnetic Switchbacks. https://doi.org/10.3847/1538-4357%2Fadc2ff

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