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arXiv · 1403.4856

Multi-Spacecraft Observations of Recurrent 3He-Rich Solar Energetic Particles

R. Bucik·D. E. Innes·U. Mall·A. Korth·G. M. Mason·R. Gomez-Herrero
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Abstract

We study the origin of 3He-rich solar energetic particles (<1 MeV/nucleon) that are observed consecutively on STEREO-B, ACE, and STEREO-A spacecraft when they are separated in heliolongitude by more than 90{\deg}. The 3He-rich period on STEREO-B and STEREO-A commences on 2011 July 1 and 2011 July 16, respectively. The ACE 3He-rich period consists of two sub-events starting on 2011 July 7 and 2011 July 9. We associate the STEREO-B July 1 and ACE July 7 3He-rich events with the same sizeable active region producing X-ray flares accompanied by prompt electron events, when it was near the west solar limb as seen from the respective spacecraft. The ACE July 9 and STEREO-A July 16 events were dispersionless with enormous 3He enrichment, lacking solar energetic electrons and occurring in corotating interaction regions. We associate these events with a small, recently emerged active region near the border of a low-latitude coronal hole that produced numerous jet-like emissions temporally correlated with type III radio bursts. For the first time we present observations of 1) solar regions with long-lasting conditions for 3He acceleration and 2) solar energetic 3He that is temporary confined/re-accelerated in interplanetary space.

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R. Bucik, D. E. Innes, U. Mall, A. Korth, G. M. Mason, R. Gomez-Herrero. 2014-03-19. Multi-Spacecraft Observations of Recurrent 3He-Rich Solar Energetic Particles. https://doi.org/10.1088/0004-637x/786/1/71

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