A study on interactions between ions and polarized Alfvén waves below cyclotron resonance frequency

Ion heating by different polarized Alfven waves below the cyclotron resonance frequency is studied using test-particle simulation. The results indicate that the interactions between ions and waves are affected by the polarization and frequency of the waves. If the frequency of waves is higher ( ω > 0.1 Ω p), the interactions between ions and left-hand (LH) waves are stronger than right-hand (RH) waves due to the sub-cyclotron resonance. However, with the decrease of the frequency, the interactions between different polarized Alfven waves and particles tend to be the same. The heating effects of LH waves on ions are better than RH waves at higher frequencies. When the frequency of the waves is lower enough ( ω < 0.1 Ω p), the heating effects of LH waves and RH waves on ions are almost identical. The change of heating efficiency with the polarization and frequency of the waves is consistent with the change of the heating effect.