Operation and Performance of a Compact, Isochronous Cyclotron

Abstract

The apparent need for an inexpensive, reliable, and easy-to-operate cyclotron for isotope production, trace element analysis, and nuclear medicine has led to the design and construction of a 30-inch AVF cyclotron. This cyclotron has accelerated very stable beams of protons to 15 MeV, deuterons to 8 MeV, He3++ to 20 MeV, and alpha particles to 16 MeV. External beam currents in excess of 50 μA have been obtained for protons and deuterons. The required magnetic field for acceleration of all four particles is attained in a three-sector configuration without the use of profile coils. Two 120° dees provide an energy gain of 100 keV per turn. The ion source, using ion-heated cathodes instead of the usual hot-filament, has allowed internal beams of more than one mA of protons and deuterons to be accelerated to full energy. A 30 μA external beam of 15 MeV protons has also been obtained by accelerating and stripping H- ions.