In the GAMMA 10 tandem mirror, production of the high beta plasmas is one of the most important themes. Fundamental ion cyclotron resonance heating produces the hot ion mode in GAMMA 10 [1]. Because ions are accelerated to the perpendicular direction to the magnetic field line in the ion cyclotron resonance layer, plasmas with the strong temperature anisotropy are formed. When the temperature anisotropy becomes strong, the magnetic field fluctuation has been clearly observed by using magnetic probes. This instability has been identified as spontaneously excited Alfvén Ion Cyclotron (AIC) mode [2]. The AIC mode in GAMMA 10 has been observed under the conditions well below the threshold predicted theoretically. Stabilizing the AIC mode contributes improvement of the particle confinement because axial particle loss is enhanced when the AIC mode is excited.
Up to now, the AIC mode in the plasmas, which have one component in the ion species and temperature, has been studied. In this report, the excitation of the AIC mode in the plasmas with multiple temperature components and/or multiple ion species is studied by solving the dispersion relation. Plasmas will have multiple temperature components when the perpendicular injection of neutral beams and an additional ICRF heating are used.
In GAMMA 10, high-energy ions are produced when the high harmonic fast wave (HHFW) are applied in addition to conventional ICRF heating. The AIC modes in the plasma with the high-energy ion component are evaluated. The frequency range in which the AIC modes are excited is strongly affected from the existence of the high-energy component. The amplitude of the AIC mode depends also on those temperature components. The high-energy component enhances the excitation of the AIC mode.
The evaluation in ICRF heating on two-ion species plasmas will be advanced.

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