基于GEM的热中子探测器的优化设计研究OA

The increasing demand for high-flux neutron detection,driven by next-generation neutron sources,necessitates alternatives to conventional 3He proportional counters,which are limited by space charge effects.This paper presents the development and experimental validation of a thermal neutron detector based on Gas Electron Multiplier(GEM)technology.Key detector parameters were systematically optimized using Monte Carlo simulations(Geant4,Garfield++,SRIM).An Ar/CO2 mixture with Ar>90%was selected as the working gas,an approximately 1 μm thick 6LiF coating was employed as the neutron conversion coating,and the electric field settings were optimized to EDrift≈150 V/cm,VGEM≈400 V,and EInduction>1.0 kV/cm.A prototype detector featuring a two-dimensional readout structure with an active area of 44 mm×44 mm was fabricated based on these optimized parameters.Preliminary performance tests conducted in a thermal neutron field demonstrated that the detector achieves measurement uniformity comparable to that of a 3He proportional counter,while providing millimeter-level geometric resolution in a single measurement.The counting rates in the"X"and"Y"directions are in good agreement with the theoretical values,laying a solid foundation for subsequent measurement applications under high-flux neutron beams.