Production of high-density plasmas with high harmonic fast waves in the GAMMA 10 tandem mirror

By using high harmonic fast waves (HHFW), the density clamping due to the formation of axial eigenmodes becomes weak in the GAMMA 10 tandem mirror. The excitation of HHFW is confirmed and the transition from the mode with a large axial wave number to the mode with a small wave number is detected. The production of high-energy ions as well as high-density plasmas is observed and the initial ion-temperature dependence of the higher harmonic damping is discussed.