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arXiv · 1801.04316

Relationship between Intensity of White-Light Flares and Proton Flux of Solar Energetic Particles

Abstract

Solar energetic particles (SEPs), including protons and heavy ions, are believed to be accelerated either by CME shock or by magnetic reconnection. The latter also produces solar flares, in which the white light flares (WLFs) are among the most energetic ones. Magnetic reconnections occur in the corona and the accelerated particles propagate both downward and upward along the magnetic loops. The former is the source of flare emission and the latter is thought to be SEPs. Therefore, a comparison between flare emission and SEP events provides valuable constraint in determining the acceleration site of SEPs. We collect 43 SEP events, observed from 2010 to 2017, and investigate their correlation with WL emission and SXR flus, observed by SDO/HMI and GOES, respectively. Our preliminary results show: 1) Among 47 SEP events, 39 of which do not have detectable flare emissions in white light and SXR. 2) Most strong WLFs are not associated with SEPs. 3) No clear correlation is found between the proton flux and the equivalent area, a quantity that measures the magnitude of WLF emission. A straightforward speculation is that the acceleration process could be different for SEPs and the energetic electrons powering WLFs in the events analyzed.

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Nengyi Huang, Yan Xu, Haimin Wang. 2018-01-12. Relationship between Intensity of White-Light Flares and Proton Flux of Solar Energetic Particles. https://doi.org/10.3847/2515-5172%2Faaa602

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