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Development of neutron time-of-flight measurement system for 1.7-MV tandem proton accelerator with lithium target

  • Lim, Soobin (Department of Nuclear Engineering, Seoul National University) ;
  • Kim, Donghwan (Department of Nuclear Engineering, Seoul National University) ;
  • Kang, Jin-Goo (Department of Nuclear Engineering, Seoul National University) ;
  • Dang, Jeong-Jeung (Korea Multi-Purpose Accelerator Complex, KAERI) ;
  • Lee, Pilsoo (Korea Multi-Purpose Accelerator Complex, KAERI) ;
  • Kim, Geehyun (Department of Nuclear Engineering, Seoul National University) ;
  • Chung, Kyoung-Jae (Department of Nuclear Engineering, Seoul National University) ;
  • Hwang, Y.S. (Department of Nuclear Engineering, Seoul National University)
  • Received : 2021.03.08
  • Accepted : 2021.03.31
  • Published : 2022.02.25

Abstract

In this study, we developed a neutron time-of-flight (nTOF) measurement system for a 1.7-MV tandem proton accelerator with a target covered with 300-nm-thick lithium (Li) layer. With implementation of beam chopping module after its ion source, the accelerator is configured to operate in pulsed-beam mode with a pulse width <50 ns at 20-kHz repetition rate. This enables the gamma flash-type nTOF measurement system to identify the neutron generated with 3-MeV proton beam energy. The nTOF system consists of a 30" cylindrical NaI(Tl) and four stilbene scintillation detectors. The NaI(Tl) scintillator is placed 50 cm from the Li target to measure the time of beam irradiation on the target, and the stilbene detectors are placed 2 and 2.4 m away to measure nTOF at each location. The nTOF system successfully measured the generated neutron energy at irradiated proton energies of 2.6 and 3.0 MeV with an average energy resolution of 15%.

Keywords

Acknowledgement

This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No. 2018M2A2B3A02072240, and No. 2020M2D1A1064206).

References

  1. B.F. Bayanov, et al., Accelerator-based neutron source for the neutron-capture and fast neutron therapy at hospital, Nucl. Instrum. Methods A 413.2-3 (1998) 397-426. https://doi.org/10.1016/S0168-9002(98)00425-2
  2. G.L. Kulcinski, A.B. Wittkower, G. Ryding, Use of heavy ions from a tandem accelerator to simulate high fluence, fast neutron damage in metals, Nucl. Instrum. Methods 94 (2) (1971) 365-375. https://doi.org/10.1016/0029-554X(71)90592-1
  3. K.R. Kim, et al., Preliminary design of a new beam line at 1.7-MV tandem accelerator of KOMAC, in: Transactions of the Korean Nuclear Society Autumn Meeting, 2017.
  4. G.F. Knoll, Radioisotope Neutron Sources, Neutron Sources for Basic Physics and Applications, 1983.
  5. User Manual UM3148 DT5730/DT5725, Caen Electronics, 2020.
  6. P. Lee, et al., Characterization study of fast neutron sources based on proton accelerators at KOMAC, J. Phys. Conf. Ser. 1350 (2019) 1 (IOP Publishing).
  7. G.F. Knoll, Radiation Detection and Measurement, John Wiley & Sons, 2010.
  8. H.S. Kim, et al., Upgrade plan of the KOMAC proton linac for the atmospheric radiation test on semiconductor devices, J. Kor. Phys. Soc. 77 (5) (2020) 373-378. https://doi.org/10.3938/jkps.77.373