Auroral particle acceleration by waves

The role of waves in accelerating both electrons and ions in the auroral zo ne is discussed. Various wave generation mechanisms and acceleration proces ses including acceleration within cavitons and nonlinear potential structur es are analysed. The wave modes which we consider include waves such as kin etic Alfven waves, and lower-hybrid waves. In some cases wave amplitudes ar e found to be large enough for strong turbulence effect to play a significa nt role in the particle dynamics. These effects manifest themselves in the formation of caviton structures and large scale density striations creating local acceleration regions. A theoretical description of the different non linear processes responsible for plasma modification and acceleration will be presented. (C) 2001 Elsevier Science Ltd. All rights reserved.