1. Very narrow coronal mass ejections producing solar energetic particles
- Author
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Katarzyna Bronarska, Natchimuthuk Gopalswamy, Grzegorz Michalek, and Michael S. Wheatland
- Subjects
Physics ,010504 meteorology & atmospheric sciences ,Solar energetic particles ,Coronal hole ,activity [sun] ,Astronomy and Astrophysics ,Electron ,Astrophysics ,01 natural sciences ,Ion ,Space and Planetary Science ,Position (vector) ,020109 - Space and Solar Physics [FoR] ,Physics::Space Physics ,0103 physical sciences ,Coronal mass ejection ,Astrophysics::Solar and Stellar Astrophysics ,particle emission [sun] ,"coronal mass ejections" (CMEs) [Sun] ,coronal mass ejections (CMEs) [sun] ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Space weather forecasting - Abstract
Aims. Our main aim is to study the relationship between low-energy solar particles (energies below 1 MeV) and very narrow coronal mass ejections (“jets” with angular width ≤ 20°). Methods. For this purpose, we considered 125 very narrow coronal mass ejections (CMEs) from 1999 to 2003 that are potentially associated with low-energy solar particles (LESPs). These events were chosen on the basis of their source location. We studied only very narrow CMEs at the western limb, which are expected to have good magnetic connectivity with Earth. Results. We found 24 very narrow CMEs associated with energetic particles such as ions (protons and 3He), electrons, or both. We show that arrival times at Earth of energetic particles are consistent with onset times of the respective CMEs, and that in the same time intervals, there are no other potential sources of energetic particles. We also demonstrate statistical differences for the angular width distributions using the Kolmogorov–Smirnov test for angular widths for these 24 events. We consider a coherent sample of jets (mostly originating from boundaries of coronal holes) to identify properties of events that produce solar energetic particles (velocities, widths, and position angles). Our study presents a new approach and result: very narrow CMEs can generate low-energy particles in the vicinity of Earth without other activity on the Sun. The results could be very useful for space weather forecasting.
- Published
- 2018