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arXiv · 1712.07285

Temperature of source regions of $^3$He-rich impulsive solar energetic particle events

N. -H. Chen·R. Bučík·R. -S. Kim
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Abstract

Impulsive solar energetic particle (SEP) events originate from the energy dissipation process in small solar flares. Anomalous abundances in impulsive SEP events provide an evidence on unique, yet unclear, acceleration mechanism. The pattern of heavy-ion enhancements indicates that the temperature of the source plasma that is accelerated is low and not flare-like. We examine the solar source of the $^3$He-rich SEP event of 2012 November 20 using Solar Dynamics Observatory (SDO)/ Atmospheric Imaging Assembly (AIA) images and investigate its thermal variation. The examined event is associated with recurrent coronal jets. The Differential Emission Measure (DEM) analysis is applied to study the temperature evolution/distribution of the source regions. Preliminary results show that the temperature of the associated solar source is ranged between 1.2-3.1 MK.

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N. -H. Chen, R. Bučík, R. -S. Kim. 2017-12-20. Temperature of source regions of $^3$He-rich impulsive solar energetic particle events. https://doi.org/10.1017/s1743921317007980

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