Author/Authors :
Franzen، نويسنده , , P. and Falter، نويسنده , , H.D. and Speth، نويسنده , , Mark E. and Kraus، نويسنده , , W. and Bandyopadhyay، نويسنده , , M. and Encheva، نويسنده , , A. and Fantz، نويسنده , , U. and Franke، نويسنده , , Th. and Heinemann، نويسنده , , B. and Holtum، نويسنده , , D. and Martens، نويسنده , , C. and McNeely، نويسنده , , P. and Riedl، نويسنده , , R. and Tanga، نويسنده , , A. and Wilhelm، نويسنده , , R.، نويسنده ,
Abstract :
IPP Garching is currently developing a RF driven negative ion source for the ITER neutral beam injection system as an alternative to the present design with filamented sources. This paper reports an overview on the present status and the further prospects of the RF source development. Current densities of 26 mA/cm2 and 15 mA/cm2 have been achieved for hydrogen and deuterium, respectively, at a pressure of less than 0.5 Pa and an electron/ion ratio of 1. Size scaling experiments indicate a maximum extraction area which can be illuminated by a driver without losses of beam quality and uniformity. The preparation of a test facility for pulse lengths of up to 3600 s is proceeding; commissioning is expected end of 2004. As an intermediate step tests of a large source with the half size of the ITER source are foreseen to be commissioned in 2005.
