基于蒙特卡罗方法的α放射源能谱测量模拟

摘要

运用蒙特卡罗方法建立PIPS-α谱仪的腔室模型,模拟谱仪对α面源(238 pu)的能谱测量,通过改变放射源与探头之间的距离,模拟不同条件下α粒子的射线能谱,同时,对不同探源距条件对α射线能谱的影响进行分析;另一方面,使用谱仪在不同探源距的情况下进行α能谱实验测量,获得不同条件下α射线能谱;最后,将模拟与实验的结果进行对比,分析实验测量结果与模拟结果的相对误差,并对模拟过程及模型参数进行校正,对校正后的模型进行实验验证,使其能够应用到其他α放射源的能谱测量中,并且使其可用于单能α粒子的能谱研究,研究结果也可为α能谱测量技术提供依据,为α能谱解谱技术提供数据支持.%In the disposal of nuclear waste,regulation and classification of transuranium elements,alpha radioactivity monitoring work in special places such as nuclear arsenal,we usually use the alpha energy spectrum measuring technique.Alpha energy spectrum measurement is one of the key measurements of nuclear radiation,which occupies an important position in the field of nuclear radiation monitoring.In order to accurately analyze the impact of different source-detector distance,vacuum degree,placement angle and other factors on alpha energy spectrum measurement,we used Monte Carlo method to simulate α energy spectrum measurement,thus reduced experiment time and improved the accuracy.The Monte Carlo method was used to establish chamber model for the PIPS-alpha spectrometer,which,by changing the distance between a radiation source and detector,simulates the alpha energy spectrum.The simulation results are corrected according to the experimental results to improve the degree of agreement between experiment and simulation.Experiments show that the Monte Carlo model is accurate and can be used for simulating the impact of different source-detector-distance,vacuum degree,placement angle and other factors on alpha energy spectrum measurement.This method not can only be applied to other alpha energy spectrum measurement,but also be used in single energy spectrum research of alpha particles.The study is to provide a basis for the alpha spectrum measurement technology and data support for alpha spectrum technology.