Heating of thermal non-equilibrium ions by Alfven wave via nonresonant interaction

Pickup of thermal non-equilibrium ions by Alfven wave via nonresonant wave-particle interaction is investigated by means of analytical test-particle theory. Some interesting and new results are found. No matter what the initial velocity distribution is, if the background magnetic field, the Alfven speed, and the Alfven magnetic field are fixed, the average parallel velocity never changes when t -> infinity. Heating effects in the perpendicular and parallel direction just depend on the initial temperature, and the perpendicular temperature increase is more prominent. It is noted that the heating effect of thermal non-equilibrium ions (Kappa ions) is weaker than that of the Maxwellian. This phenomenon may be relative to the heating of ions in the solar corona as well as in some toroidal confinement fusion devices. (C) 2013 AIP Publishing LLC.