Intense heavy-ion RFQ linear accelerator and HIF study at TIT

Intense Heavy-ion linac system was proposed for basic research on Heavy-ion inertial confinement fusion. An RFQ (Radio-Frequency Quadruple) linear Accelerator was constructed. The machine was designed to accelerate particles with charge to mass ratio (q/A) of 1/16 to 1 injected at 5 keV/u up to 219 keV/u. We simulated the beam optics including effects of higher order harmonics in the intervane potential for optimization of the vane parameters. In order to increase the acceleration efficiency, synchronous phase was gradually raise from -30deg to -20deg in the accelerator section of cavity. The expected beam transmission is 91.8% for the beam current of 0 mA and 68.4% for 10 mA. The vane modulation was machined by a numerically controlled boring machine of two-dimensions. Beam acceleration test stand was constructed and the beam test have been performed by using ion beams of He⁺ and C²⁺. Transmission efficiency was measured exceeding 89% with He⁺ ion. The acceleration characteristics agree well with the computer simulation. A transport system after the RFQ for Heavy-ion-induced plasma experiments was designed by using three Quadruple magnets and a kicker. Ion beam of O⁺ with currents of 7 mA is expected to be focus to about 1 mm². (author)