Update on the Development of 120-Kev Multi-Megawatt Neutral Beam Source

The next generation of U.S. fusion experiments, which includes TFTR, MFTF, and Doublet III, will utilize neutral-beam injection for plasma heating. TFTR, for example, desires 20 MW of 120-keV deuterium atoms in pulses of 0.5-sec duration at 5-minute intervals from a total of 12 individual neutral-beam modules. A discussion is given of some of the design details of a 15-A, 120-keV, 0.5-sec ion-source module that has recently been built to test design concepts for TFTR sources, and some of the features of the facility where it is presently under test at the Lawrence Berkeley Laboratory.