New development of high intensity linear accelerator for heavy-ion inertial fusion driver

In order to verify direct plasma injection scheme (DPIS), an acceleration test was carried out using TiTech RFQ heavy ion linear accelerator and CO2 laser heavy-ion source in 2001. The accelerated carbon beam was observed successfully and the obtained current 10 mA of C4+. To confirm the capability of the DPIS, we designed and fabricated a new RFQ to accommodate 100 mA of carbon beam. We succeeded to accelerate 60 mA carbon ions with the DPIS in 2004. We have studied a multi-beam type RFQ with Interdigital-H (IH) cavity that is power-efficient structure in low energy. We designed and manufactured a two-beam type RFQ-IH linac as a prototype of the multi-beam type. As a result of the beam acceleration test of the linac for carbon beams, it had successfully to accelerate from 5 keV/u to 60 keV/u and 108 mA (2x54 mA/channel) in the output current. We believe that acceleration techniques of DPIS and the multi-beam type RFO-IH linac are brake through of 21 century for Heavy-ion Inertial confinement Fusion (HIF). Conceptual design of RF linac with these techniques for HIF is studied. New accelerator-system using these techniques for HIF basic experiment is designing to accelerate 400 mA using 4 beams from an RFQ-IH type linac with DPIS. A model of 4 beams acceleration cavity was designed and manufactured for proof of principle accelerator. (author)