RFQ linac commissioning and carbon4+ acceleration for Ag15+ acceleration via directplasma injection scheme

Various species of high intensity highly charged state heavy ion beams with smallemittance are required in many fields including particle physics, medical uses, inertialfusion, and simulator of space radiations. Direct Plasma Injection Scheme (DPIS), we havedeveloped for several years, is a unique scheme to provide heavy ion beams to meet theabove requirements. A high-density plasma created by a laser ablation with an initial driftvelocity flies to entrance of a Radio Frequency Quadrupole (RFQ) LINAC; ions will beseparated from plasma via high voltage at the inside of the RFQ LINAC. Then ions arecaptured by the RF buckets and are accelerated remaining high current over 10mA. In thepast, we had accelerated carbon4+, carbon5+, and carbon6+ using a RFQ with partiallymodulated vanes. Due to the un-modulated section of the electrodes, accelerated beams werenot bunched. In 2011, we replaced the vanes with a newly designed one. The designed chargeto mass ratio (q/A) is 1/6 and the output energy is 270 keV/u. The beam commissioning withcarbon 4+ was successfully carried out. In the next step we'll try to accelerate carbon 2+(q/A=1/6), which is to demonstrate the feasibility of the Ag+15 ion acceleration. Copyright