Fusion Science and Technology / Volume 47 / Number 1T / January 2005 / Pages 96-99
Technical Paper / Open Magnetic Systems for Plasma Confinement
In the GAMMA 10 tandem mirror device, an experimental plan of high power ECRH is now under way. As the first step, operation of existing gyrotrons for plug ECRH has been carried out at a power exceeding their nominal powers of 200 kW. In this step, the highest recorded value of [varphi]c for a hot ion mode plasma is 1.4 kV at Pplug = 240 kW. The effective temperature Teff of the end loss electrons as a scaling factor of the axial potential distribution has attained to 3 keV at a heating power of 260 kW and the potential difference between the plug to the end plate has exceeded 5 kV. Then, the potential range of the scaling between and Teff has been expanded. Use of a new gyrotron delivering much higher power is the second step. The first experimental campaign with this gyrotron has just started.