以水作为慢化体的多球中子谱仪模拟与解谱研究

Simulation and spectrum unfolding of multi-sphere neutron spectrometer with water as moderator

中子能谱的测量是核辐射探测领域的一个重要研究课题,它在整个中子辐射防护检测中具有重要地位,与中子辐射剂量关系密切.多球中子谱仪是进行中子能谱测量的常见工具,具有非常多的优势,首先操作简单方便;其次功能强大,主要表现在测量范围上,相比较于其他类似设备来说要大许多;最后在灵敏性方面十分出色.本研究分别采用水和聚乙烯作为多球中子谱仪的慢化体,使用蒙特卡罗程序Geant4,计算了10-9~102 MeV能量范围中60个能量点的响应函数,并分析比较;利用Gravel少道解谱算法,对不同中子场中的水慢化体多球中子谱仪测量数据进行解谱,数据显示水可以用作慢化体在设备中使用.该研究为水用作慢化体在设备中使用提供了理论和模拟研究基础.

Neutron energy spectrum measurement is an important research topic in the field of nuclear radiation detection.It plays an important role in the whole neutron radiation protection detection and is closely related to the neutron radiation dose.Multi-sphere neutron spectrometer is a common tool for neutron spectrum measurement.It has many advantages.First of all,it is simple and convenient to operate.Secondly,it is powerful,mainly in the measurement range,which is much larger than other similar equipment.Finally,it is very good at sensitivity.In this paper,water and polyethylene are used as the moderators of multi-sphere neutron spectrometers respectively,and the Monte Carlo program Geant4 is used to calculate the response functions of 60 energy points in the energy range of 10-9MeV to 102MeV,and the neutron response function curves of the two kinds of multi-sphere neutron spectrometers are compared.Using the Gravel few-channel spectrum unfolding algorithm,we measured data of the water moderator multi-sphere neutron spectrometer in different neutron fields.The spectrum unfolding results show that it is feasible to use water as the moderator of the multi-sphere neutron spectrometer.The research results provide a theoretical and simulation basis for the use of water as a moderator in equipment.