Development of a high duty factor, surface conversion H/sup -/ ion source for the LANSCE facility

Abstract

The next generation spallation neutron sources, such as the upgrade to the Los Alamos Neutron Science Center (LANSCE) will require high intensity negative hydrogen (H/sup -/) beams. The new LANSCE source in particular will need to generate 40 mA of H/sup -/ beam current at a duty factor of 12% (1 ms pulse at 120 Hz). One option that we are currently studying concerns altering the existing LANSCE source to utilize an RF induction plasma discharge. However, before proceeding with any changes a full understanding and optimization of our current prototype ion source was required. This surface conversion source, similar to the present LANSCE source, will be used as a benchmark against which to measure future modifications, as well as to provide direction for those modifications. Results to date along with future plans will be presented.