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arXiv · 1701.04286

Solar Energetic Particle transport near a Heliospheric Current Sheet

Markus Battarbee·Silvia Dalla·Mike S. Marsh
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Abstract

Solar Energetic Particles (SEPs), a major component of space weather, propagate through the interplanetary medium strongly guided by the Interplanetary Magnetic Field (IMF). In this work, we analyse the implications a flat Heliospheric Current Sheet (HCS) has on proton propagation from SEP release sites to the Earth. We simulate proton propagation by integrating fully 3-D trajectories near an analytically defined flat current sheet, collecting comprehensive statistics into histograms, fluence maps and virtual observer time profiles within an energy range of 1--800 MeV. We show that protons experience significant current sheet drift to distant longitudes, causing time profiles to exhibit multiple components, which are a potential source of confusing interpretation of observations. We find that variation of current sheet thickness within a realistic parameter range has little effect on particle propagation. We show that IMF configuration strongly affects deceleration of protons. We show that in our model, the presence of a flat equatorial HCS in the inner heliosphere limits the crossing of protons into the opposite hemisphere.

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Markus Battarbee, Silvia Dalla, Mike S. Marsh. 2017-01-16. Solar Energetic Particle transport near a Heliospheric Current Sheet. https://doi.org/10.3847/1538-4357/836/1/138

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