Beam Commissioning of the Heavy-ion Accelerator RAON

RAON (Rare-isotope Accelerator complex for ON-line experiments) is the superconducting linac (SCL3 and SCL2) facility in Korea. It consists of an injector, a superconducting linac, and user facilities. It is designed to accelerate various ion beams from proton (A/Q=1) to uranium (A/Q=7.2). The ECR ion source in the injector system generates ion beams with the energy of 10 keV/u. They are accelerated to the energy of 500 keV/u by the RFQ (Radio-Frequency Quadrupole) in the injector. The superconducting linac (SCL3) includes 22 QWR (Quater-Wave Resonator) cavities and 102 HWR (Half-Wave Resonator) cavities. The energy becomes 18.5 MeV/u for uranium beams after the linac. The beam commissioning of the injector started from August 2021. The first beam commissioning of the superconducting linac was performed from October 2022 to June 2, 2023. Research and development of the cavities for the high-energy part (SCL2) of the superconducting linac is in progress. This work explains some characteristic features of the beam dynamics for RAON linac and some beam commissioning results.