Measurements of the negative ion beam emittance for the JAERI tandem accelerator

Abstract A computer controlled emittance measuring device has been constructed for the JAERI tandem accelerator system. The emittance values were measured in the accelerator beam line for proton, oxygen, silicon, nickel and iodine beams. They were extracted from a negative sputter ion source and accelerated up to 220 keV. In the measurements, the suppression voltage was used to exclude the effects of the secondary electrons emitted from the beam detectors and their surrounding materials. The emittance values together with their associated current intensity distributions were obtained to be satisfactory.