A kinetic model for resonant heating of ions by Alfven waves in laboratory plasmas

摘要

A kinetic model for the resonant heating of ions by Alfven waves that propagate along the magnetic field lines and wave frequencies in the ion-cyclotron frequency range is developed. In terms of the quasi-linear approach, particle-Alfven wave interactions are examined from the Vlasov equation in a hot, magnetized, and multi-ion plasma. Consequently, a new heating-rate expression for any species of ions that are heated by the Alfven waves is derived. Based on the heating model and the dispersion relation of the magnetic field-aligned left-hand polarized EM ion-cyclotron-Alfven (EMICA) waves, the resonant heating of H, H-2, H-3, He-3, and He-4 by the EMICA waves in a typical preheated laboratory plasma is numerically studied. The results indicate that the EMICA waves can efficiently heat ions through the cyclotron resonances. The temperatures of H, H-2, H-3, He-3, and He-4 can be increased by a factor of tens within hundreds of mu-seconds. The parameters that affect the EMICA-wave heating include the plasma density, the plasma temperature, the background magnetic field, and the wave-energy density. It is also dependent on the ion species. Each species of ions resonates with the EMICA waves in a narrow frequency range that is close to its ion-cyclotron frequency. (C) 2004 American Institute of Physics.