ION SOURCES FOR MEDICAL ACCELERATORS

Advanced injector systems for proton synchrotrons and accelerator-base d boron neutron capture therapy systems are being developed at the Law rence Berkeley National Laboratory. Multicusp ion sources, particularl y those driven by radio frequency, have been tested for these applicat ions. The use of a radio frequency induction discharge provides clean, reliable, and long-life source operation. It has been demonstrated th at the multicusp ion source can provide good-quality positive hydrogen ion beams with a monatomic ion fraction higher than 90%. The extracta ble ion current densities from this type of source can meet the inject or requirements for both proton synchrotron and accelerator-based boro n neutron capture therapy projects. (C) 1998 American Institute of Phy sics.