Production of Solar Energetic Ions Associated with Flares

Abstract

An acceleration process which may occur in solar active regions is proposed to explain the origin of energetic particles associated with solar flares. The scenario suggested may be described as follows: first, newborn ions, protons, as well as minor heavy ion species, produced continuously in the upper chromosphere through the lower corona can excite Alfven waves near a reconnection region. We suggest that the build up of Alfvenic turbulence in that region can lead to rapid acceleration of newborn protons created later to energies as high as several 10e100 MeV via a pickup process. Proton acceleration takes place mainly inside the reconnection layer. However, the enhanced Alfven waves can also energize minor heavy ions outside or away from the reconnection layer. The present model suggests that ascending as well as descending energetic ions can be produced at the same time, as implied by observations. Furthermore, since energetic ions can carry electrons with them due to charge and current neutrality conditions, the model also explains solar energetic electrons of the order of 10e100 keV as well.