Ionization efficiencies for highly charged stable and radioactive ions in the AECR-U ion source

Ionization efficiencies for high charge state ions have been measured with the LBNL AECR-U ion source for ion beams produced from stable and radioacti ve gases. Various calibrated gas leaks from stable CO, CO2, O-2, Ne, Ar, CH F3, Kr and Xe were used in the measurements. Ionization efficiencies as hig h as 25% or higher were measured for O-16(6+) and C-12(4+) ion beams and mo re than 10% for high charge state stable ion beams of Ar, Kr and Xe. In add ition, ionization efficiency measurements for radioactive species of C-11 a nd O-14 were carried out in which an efficiency of more than 10% for C-11(4 +) was achieved. (C) 2000 Elsevier Science B.V. All rights reserved.