A NEUTRAL LITHIUM BEAM SOURCE

A low energy neutral lithium beam source with energy about 6 keV and a neutral beam equivalent current of 20 muA/cm2 has been developed in A SIPP in order to measure the density gradient and the fluctuations in the edge plasma of the HT-6M tokamak. In the source, lithium ions are extracted from a solid emitter (beta-eucryptite), focused in a two-tub e immersion lens, and neutralized in a charge-exchange cell with sodiu m. This source operates in pulsed mode. The pulse length is adjustable from 10 to 100 ms.