GEM 검출기를 이용한 중성자 빔 선량 측정 장치 개발

In this study, we perform a simulation of a structure combining a boron-based neutron converter and a gas electron multiplier (GEM) detector to improve the neutron detection efficiency used in various fields such as nuclear fusion, boron neutron capture therapy (BNCT), and high-level nuclear waste disposal. Using Geant4, the detection efficiency is evaluated by using the energy loss in the detector gas of alpha particles and Li nuclei generated after neutron capture as the basis for signal generation, with a cold neutron with 10 meV on kinetic energy. In the simulation, the neutron detection efficiency is estimated by applying the proper threshold (the signal due to 0.48 MeV gamma rays is judged as noise) for three configurations: a boron plate, a cathode foil coated alone, and a boron-coated on both of cathode GEM foil. As a result, it is confirmed that when only the cathode coating is performed, a detection efficiency of approximately 5.81% is achieved, and when boron is coated on the both of cathode and GEM foil, an improvement in detection efficiency of approximately 10.97% could be expected.