Alfv6n wave Excitation Due to Pressure Anisotropy in the GAMMA1O Tandem Mirror

Alfvdn ion cyclotron (AIC) modes are driven by a strong temperature anisotropy in the case of the high power ion cyclotron range of frequency (ICRF) heating on the GAMMAI0 tandem mirror. Parameters on which the AIC modes are observed in the GAMMAI0 are much smaller than the theoretically predicted parameters. The axial structure of the AIC modes is measured by magnetic probes and depends strongly on the axial pressure profile. It is suggested that the axial boundary condition is essential for the excitation of the AIC modes.