Production of Irotons and Negative Ions with Low Energy Spread

The suitability of the duoplasmatron and RF ion source for the production of low energy spread beams required for klystron bunching on Van de Graaff accelerators has been investigated. An increase in the proton and negative ion beams obtained from the duoplasmatron source can be achieved by extracting from the edges of the arc. The energy spread depends on the source conditions and varies from 8 to 50 eV. In RF sources the energy spread is influenced by the oscillator design and coupling and is less than 50 eV for a push-pull system.