Speaker
Description
Korea Broad acceptance Recoil spectrometer and Apparatus (KoBRA) was constructed at the Institute for Rare Isotope Science (IRIS), as a part of the Rare isotope Accelerator complex for ON-line experiments facility (RAON) in Korea [1−3]. Stable isotope (SI) or radioactive isotope (RI) beams can be produced using Electron Cyclotron Resonance (ECR) ion sources or the Isotope Separation On-Line (ISOL) system at RAON, respectively, and these beams can be delivered to KoBRA at energies of 1 − 40 MeV/u via the SuperConducting Linear accelerator 3 (SCL3). KoBRA will serve as a multi-purpose experimental instrument to cover various studies of low-energy nuclear physics−encompassing nuclear reaction, astrophysics, and nuclear structure−by capitalizing on its large momentum and angular acceptances (∆p/p = 8% and Ω = 13.9 msr) together with the RAON facility’s capabilities of providing various SI and RI beams over a wide low-energy range.
KoBRA has been in the beam commissioning phase since May 2023, following its off-line beam commissioning using an $^{241}$Am α-particle source. In this early commissioning phase, 16-MeV/u $^{40}$Ar primary beam was successfully transported, and secondary RI beams produced from the reaction $^{40}$Ar + $^{12}$C were investigated. Particle identification was performed using standard methods based on energy loss (∆E), time-of-flight (ToF), and magnetic rigidity (Bρ). Furthermore, 16-MeV/u $^{25}$Na radioactive isotope beam produced from the ISOL system was transported to KoBRA, and its beam energy, particle identification, and purification were examined. In this presentation, we will report on the recent progress of KoBRA beam commissioning, along with the preliminary experimental results.
References
[1] K. Tshoo et al., Nucl. Instrum. Methods Phys. Res. B 317 (2013) 242−247.
[2] K. Tshoo et al., Nucl. Instrum. Methods Phys. Res. B 376 (2016) 188−193.
[3] K. Tshoo et al., Nucl. Instrum. Methods Phys. Res. B 541 (2023) 56−60.
This work was supported by the Institute for Basic Science (IBS-I001-01) and the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2013M7A1A1075764, RS-2022-00165168, RS-2023-00282876), Republic of Korea.
