Small electron acceleration episodes in the solar corona

Abstract

We study the energetics of nonthermal electrons produced in small acceleration episodes in the solar corona. We carried out an extensive survey spanning 2004--2015 and shortlisted 6 impulsive electron events detected at 1 AU that was not associated with large solar flares(GOES soft X-ray class $>$ C1) or with coronal mass ejections. Each of these events had weak, but detectable hard Xray (HXR) emission near the west limb, and were associated with interplanetary type III bursts. In some respects, these events seem like weak counterparts of "cold/tenuous" flares. The energy carried by the HXR producing electron population was $\approx 10^{23}$ -- $10^{25}$ erg, while that in the corresponding population detected at 1 AU was $\approx 10^{24}$--$10^{25}$ erg. The number of electrons that escape the coronal acceleration site and reach 1 AU constitute 6 % to 148 % of those that precipitate downwards to produce thick target HXR emission.

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Cited by in corpus (10)

• A Statistical Study of Solar Radio Type III Bursts and Space Weather Implication
• Spatial expansion and speeds of type III electron beam sources in the solar corona
• Electron Acceleration and Jet-Facilitated Escape in an M Class Solar Flare on 2002 August 19
• Connecting solar flare hard X-ray spectra to in situ electron spectra. A comparison of RHESSI and STEREO/SEPT observations
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• Periodicities in an active region correlated with Type III radio bursts observed by Parker Solar Probe
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• Energetics of small electron acceleration episodes in the solar corona from radio noise storm observations
• A Brief Review on Particle Acceleration in Multi-island Magnetic Reconnection
• Estimating the total energy content in escaping accelerated solar electron beams