PARTICLE-ACCELERATION IN AN EVOLVING ACTIVE-REGION BY AN ENSEMBLE OF SHOCK-WAVES

We present a model for the acceleration and transport of energetic par ticles (electrons and ions) inside an active region. We propose that t he agent for the acceleration is an ensemble of oblique shock waves, g enerated inside an evolving and constantly changing active region. The acceleration is based on the ''shock drift'' mechanism, using the adi abatic treatment. The high-energy particles are losing energy via Coul omb 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 particl es are transported inside a chaotic magnetic field and are reflected r andomly when they meet a magnetic mirror point. Finally we compare our numerical results with the observations.