On the origin of the energetic storm particles
Abstract
Energetic storm particles (ESP) are events that are commonly known to occur in association with the passage of interplanetary shock waves. Selected periods of proton data (0.7 - 7.6 MeV) from the cosmic ray experiments on board of Explorer 34 and 41 corresponding to the intervals May 1967 - March 1969 and February - September 1972 are analyzed. It is found that there exist distinct flux peaks approximately 8 hours behind the shock waves. These peaks show a more clear configuration for events generated by eastern (from the sun's central meridian) flares. Also they exhibit anisotropies along directions presumably coincident with the interplanetary field lines. A model to explain the possible origin of the ESP events is developed. According to this model the ESP events are particles that propagate directly from the sun along the tangential discontinuity field lines which is expected to be formed in front of the piston-driven gas. A smoothing-field mechanism is suggested to account for the relative coherency of the particles.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- September 1975
- Bibcode:
- 1975STIN...7617010M
- Keywords:
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- Interplanetary Magnetic Fields;
- Particle Energy;
- Shock Waves;
- Explorer 34 Satellite;
- Explorer 41 Satellite;
- Proton Flux Density;
- Solar Flares;
- Solar Physics