天然辐射场γ射线谱分布的MC模拟研究

MC Simulation Study of γ-Ray Spectral Distribution in Natural Radiation Field

摘要: 天然辐射γ的测量一直是野外测量的一个重要问题。本文采用MCNP软件模拟了天然地–空界面不同矿质组分下的γ射线谱以及NaI探测器置于不同高度所得的谱线。通过对比和分析，得到距离对天然γ能谱的影响以及不同矿层能谱的差异。所得到的模拟结果较好地反映了理论上γ能谱的分布规律，为自然辐射场中γ射线谱的分布情况提供了可靠的解释依据，并给天然环境辐射水平的监测和评价提供了参考方法，从而为野外测量等提供一些指导。

Abstract: The measurement of natural radiation γ has always been an important issue for field measurement. In this paper, MCNP software is used to simulate the γ-ray spectra under different mineral components at the natural ground-air interface and the spectral lines obtained by placing the NaI detector at different heights. Through comparison and analysis, the influence of distance on natural γ energy spectrum and the difference of energy spectrum of different mineral layers are obtained. The obtained simulation results better reflect the theoretical distribution of γ energy spectrum, provide a reliable explanation basis for the distribution of γ-ray spectrum in the natural radiation field, and provide a reference for the monitoring and evaluation of the natural environmental radiation level Method, so as to provide some guidance for field surveys.