On the Acceleration Process in Solar Flares
Abstract
The paper summarizes the data on the acceleration processes on the sun. Four different instabilities are distinguished: (1) one with purely thermal consequences giving rise to the origin of any flare; (2) a nonthermal process at the flash phase of flares giving rise to nearby 100 keV electrons and protons, manifested through hard X-ray and impulsive microwave bursts; (3) an instability giving rise to streams of electrons, without accelerating protons, manifested by type III bursts; when (2) and (3) are linked, flare associated electron events in space are often recorded; and (4) an explosive instability produces a shock wave which manifests itself as a type II burst. This instability leads to a second-step acceleration of particles preaccelerated in (2) and gives origin to more than 10 MeV protons and relativistic electrons.
- Publication:
-
Solar Gamma-, X-, and EUV Radiation
- Pub Date:
- 1975
- Bibcode:
- 1975IAUS...68..427S
- Keywords:
-
- Microwave Emission;
- Particle Acceleration;
- Solar Flares;
- Solar Radio Bursts;
- Solar X-Rays;
- Thermal Instability;
- Particle Energy;
- Proton Flux Density;
- Relativistic Particles;
- Shock Waves;
- Solar Flux Density;
- Type 2 Bursts;
- Type 3 Bursts;
- Type 4 Bursts;
- Solar Physics