Design study of Beam Loss Monitoring system for the Rare Isotope Science Project in Korea

Abstract

A new heavy ion accelerator facility called RAON is being constructed in Daejeon, Korea to produce rare isotope beams of various energies for the Rare Isotope Science Project (RISP). This facility is designed to use both the In-flight Fragmentation (IF) and Isotope Separation On-Line (ISOL) systems to provide a wide range of rare isotope beams to be utilized in many fundamental physics experiments and in various applications. The RAON can use both stable heavy ion beams and rare isotope beams with energies up to a few hundreds of MeV/u with 400 kW of beam power. One of the greatest challenges in operating such a high beam power facility (similar to 400 kW) is to accurately monitor the beam loss and trigger the Machine Protection System (MPS) reasonably quickly. In this paper, we report the conceptual design of the RAON beam loss monitoring system. Monte Carlo simulations using the MCNPX code were performed to understand beam loss-induced neutron and gamma radiation. The types of detectors were determined based on radiation simulations while considering the sensitivities of the detectors and response time requirements.