Neutralization principles for the extraction and transport of ion beams

The strict application of conventional extraction techniques of ion beams f rom a plasma source is characterized by a natural intensity limit determine d by space charge. The extracted current may be enhanced far beyond this li mit by neutralizing the space charge of the extracted ions in the first ext raction gap of the source with electrons injected from the opposite side. T he transverse and longitudinal emittances of a neutralized ion beam, hence its brightness, are preserved. Results of beam compensation experiments, wh ich have been carried out with a laser ion source, are resumed for proposin g a general scheme of neutralizing ion sources and their adjacent low-energ y beam transport channels with electron beams. Many technical applications of high-mass ion beam neutralization technology may be identified: the enha ncement of ion source output for injection into high-intensity, low- and hi gh-energy accelerators, for ion thrusters in space technology, for the neut ral beams needed for plasma heating of magnetic confinement fusion devices, and for future accelerator-driven systems for fusion, fission and nuclear waste incineration. (C) 2000 Elsevier Science B.V. All rights reserved.