HIGH-DENSITY PLASMA PRODUCTION FOR NEUTRALIZING NEGATIVE-ION BEAM

An electron cyclotron resonance (ECR) plasma production method using e lectron cyclotron wave is presented. This method is not subjected to a ny cutoff-density scaling, and is capable of generating dense plasmas far beyond the critical density of an ordinary wave. It has been demon strated that a plasma density more than 10(13) cm(-3) (argon) is obtai ned with a low frequency (2.45 GHz) and low power (11 kW) microwave. T he experimental results and the application to plasma neutralizer are described. The experimental verification of superpermeability of Nb me mbrane in a plasma environment is in progress to develop a plasma neut ralizer with Nb-membrane wall. The design parameters of Nb-membrane pu mp are presented. (C) 1998 American Institute of Physics.