Long pulse H− beam extraction with a rf driven ion source on a high power level

W. Kraus, U. Fantz, P. Franzen
2010 Review of Scientific Instruments  
IPP Garching is investigating the applicability of RF driven negative ion sources for the NBI of ITER. The set-up of the tested source was improved to enable long pulses up to 100 kW RF power. The efficiency of negative ion production decreases at high power. The extracted Hcurrents as well as the symmetry of the plasma density close to the plasma grid and of the beam divergence depend on the magnetic filter field. The pulse duration is limited by the increase of co-extracted electrons, which
more » ... pends on the RF power and the Caesium conditions on the plasma grid.
doi:10.1063/1.3273065 pmid:20192417 fatcat:hmtfnvfkk5e2bokka77ntarcma