ION SOURCES FOR RADIOACTIVE BEAMS AND RELATED PROBLEMS (REVIEW)

Ion sources for radioactive beam facilities are integrated systems of production target and ionizer which have to convert the limited number of particles produced in nuclear reactions efficiently and selectivel y into an ion beam. The figures of merit for such a system are thus it s efficiency for a desired isotope and its discrimination against the unwanted elements. The efficiency is the product of release efficiency (a characteristic of the integrated system) and ionization efficiency , the latter characterizing the ionizing mechanism. The ionizers descr ibed include both the ones routinely used in isotope separation on-lin e as well as promising new developments; they are classified according to their ionizing medium, utilizing electrons, heat, or photons, resp ectively. (C) 1996 American Institute of Physics.