Status of the RAON heavy-ion accelerator

The Rare Isotope Accelerator Complex for ON-line experiments (RAON) is an accelerator facility capable of generating and accelerating both stable and unstable heavy ions for various scientific research on rare isotopes. The facility can produce a variety of rare isotope beams using both the in-flight fragmentation and the isotope separation on-line methods. A unique feature of the RAON is its ability to produce very exotic rare isotope beams by combining the isotope separation on-line and the in-flight fragmentation methods. The in-flight fragmentation system is driven by a superconducting linear accelerator to accelerate heavy ions, while the isotope separation on-line system is driven by a 70-MeV proton cyclotron. The ultimate goal of the RAON is to accelerate various ion beams, ranging from protons to uranium, up to a beam power of 400 kW. After an 11-year construction project, which started in December 2011, the first beam extraction from the low-energy superconducting linear accelerator was achieved in May 2023. In this review, we describe the current status of the RAON heavy-ion accelerator, including the results of the initial beam commissioning of the low-energy linear accelerator.