Design and fabrication of a surface conversion negative ion source and an 80 keV pre-accelerator

The design and fabrication of a surface conversion negative ion source and an 80 keV pre-accelerator intended for use as a proof-of-principle demonstration leading to a radiation-hardened 400 keV TFF based beamline for the next generation mirror or tokamak reactor will be described in this paper. Experience gained in a previous source and accelerator module was utilized to redefine the overall design and construction for this second generation CW device. The source will provide 1 to 2 amps of H/sup -/ for acceleration by a 3 electrode 80 keV preaccelerator. Particular attention was placed on the mounting of the source to the primary high-voltage insulator, the insulator itself, magnet installation, converter shape and construction, cesium injector and exit aperture design, and accelerator construction, with an overall emphasis on serviceability