Particle acceleration in an evolving active region by an ensemble of shock waves, ApJ 428, 819, 1994


Abstract

We present a model for the acceleration and transport of energetic particles (electrons and ions) inside an active region. We propose that the agent for the acceleration is an ensemble of oblique shock waves, generated inside an evolving and constantly changing active region. The acceleration is based on the `shock drift' mechanism, using the adiabatic treatment. The high energy particles are losing energy via Coulomb collisions and radiation. We calculate the energy distribution of the particles, their acceleration time and their maximum energy as a function of the number of shock waves present. The high energy particles are transported inside a chaotic magnetic field and are reflected randomly when they meet a magnetic mirror point. Finally we compare our numerical results with the observations.

Subject headings : particle acceleration -- shock waves -- Sun: Corona -- Sun: flares