基于超高分辨γ射线探测器的蒙特卡罗模拟

能量分辨率是γ射线探测器关键技术指标之一,直接关联γ射线全能峰的尖锐程度、分离程度,从而影响全能峰被识别、区分的能力。提高γ探测器的能量分辨率,是γ探测器发展的一个重要方向,近年发展起来的超高分辨γ射线探测器,能达到25 e V@103 ke V的能量分辨率,其相对目前能量分辨率最好的高纯锗探测器的能量分辨率高一个数量级,因此超高分辨超导γ射线探测器成为了一大研究热点。为了推动超高分辨率γ探测器关键技术的实验研究,利用MCNP5采用了不同能量的射线源、不同规格的吸收体以及不同的支撑环境对超高分辨超导γ射线探测器的探测结果进行了模拟。这些模拟对于探测器的模型优化以及谱仪的设计有重要的指导作用。

Monte Carlo Simulation of Ultra-high Resolution γ Detector

The ultra-high energy resolution detector based on superconducting micro-calorimeters (transition edge-sensor) has been developed for improving the NDA (non-destructive analysis) method on radiation material.The resolution is the most important parameter related to the ability of distinguish the energy peaks.Because the energy resolution of the ultra-high energy resolution detector,which is needed in detecting nuclear materials,is better than the HPGe detector,the ultra-high energy resolution detector has great promise for applications in the fields of homeland safeguard.To research on interaction between the gamma rays and the detector,this pape simulates the ultra-high resolution detector with different sources and absorbers by using MCNP5.This paper described the results of the simulation with different materials,shapes and detectors.The ultra -high resolution gamma ray detector has advantages in isotopic abundance measurement.The results can help to understand the spectral response function and to optimize the detector geometry.