Investigation of charge exchange in ion sources

Abstract

Charge exchange phenomena in a calutron ion source were investigated using a reflecting grating spectrograph. Doppler shifts observed in ionized calcium spectra from the source region of an electromagnetic isotope separator correspond to ion velocities of up to ∼ 7 × 10 7 cm/sec in the accelerating region. These maximum velocities are greater than would be expected from the potential difference between the electrodes and are due to the charge exchange of doubly charged ions after being partially or fully accelerated. High velocity neutral calcium particles due to charge exchange of singly charged ions are also observed. These charge exchange phenomena in the accelerating region are probably responsible for a part of the isotopic contamination present in collected isotopes. In an alternative approach, Aston bands resulting from charge exchange phenomena were studied directly in the isotope separator.