Compact Integration and RF Commissioning of the C-Band 9-MeV Electron Linear Accelerator at the Dongnam Institute of Radiological & Medical Sciences

Abstract

The 6-MeV C-band standing-wave accelerator was constructed in 2015 and is providing for the beam service. The new 9-MeV accelerator was designed and constructed in 2018 at the Dongnam Institute of Radiological & Medical Sciences (DIRAMS), Busan, Korea. The 5712 MHz accelerating column was designed with an average accelerating gradient of 16.7 MV/m at a pulsed resonance frequency (RF) power of 2.5 MW. The C-band coaxial magnetron was chosen for its high RF power of 2.5 MW and RF frequency of 5712 ± 10 MHz. While the 6-MeV accelerator was operating using a magnetron manufactured by BVERI, China, the 9-MeV accelerator uses a magnetron manufactured by CPI, USA. Though the CPI magnetron requires more heating power and precise heating control for high repetition operation, the frequency spectrum and the RF power distribution are satisfactory for our accelerating columns. The magnetron installed on the 9-MeV accelerator was tested with the 6-MW pulse modulator based on the thyratron-switched pulse-forming network and is currently operating for accelerator RF conditioning. In this paper, we present a brief description of the 9-MeV accelerator, the integration of the RF transport systems and the commissioning status. We also discuss the results obtained during the early commissioning and future plan.