Abstract
Preferential acceleration of 3He ions by H cyclotron waves excited via nonlinear effects of strong current-driven instabilities is studied. The plasma is assumed to consist of electrons, H, 4He and 3He ions with the abundance of 3He being very small. First, by means of a two-dimensional, electrostatic, particle simulation code, it is demonstrated that 3He ions are selectively accelerated by fundamental H cyclotron waves with frequencies ω\\simeq2Ω3He (Ω3He is the cyclotron frequency of 3He). These waves grow to large amplitudes in a plasma with the electron temperature parallel to the magnetic field Te|| higher than the ion temperature TH. Next, frequencies and growth rates of H cyclotron waves in a plasma with Te||>TH are studied theoretically and numerically. The condition under which the waves with ω\\simeq2Ω3He become dominant is investigated. It is found that these waves have the greatest growth rates for a large region of the plasma parameters; Te||⁄TH\\gtrsim10 mush be satisfied. It is then suggested that these waves can play an essential role in 3He rich events in solar flares.
