Scattered neutron background in thermal neutron detectors
Scattered neutron background in thermal neutron detectors
复制标题
DOI：
10.1016/j.nima.2018.04.055
复制
发表时间：
2018-09-11
影响因子：
1.4
通讯作者：
Zagyvai, P.
中科院分区：
文献类型：
--
作者：
Dian, E.;Kanaki, K.;Zagyvai, P.
非弹性中子散射仪器需要非常低的本底;因此，抑制散射中子本底的适当屏蔽，无论是从弹性和非弹性散射是必不可少的。为了有效地抑制背景散射，需要对背景散射源有详细的了解。多栅极热中子探测器是一种填充Ar/CO2气体的探测器，在铝基底上涂覆有（B4 C）-B-10中子转换器。这是一个大面积探测器设计，将装备在欧洲中子源（ESS）的非弹性中子谱仪。为此，为多网格探测器构建了参数化的Geant 4模型。这是第一次在探测器响应的详细模拟中对热中子散射背景源进行建模。通过与ILL的IN 6仪器和SNS的CNCS仪器上安装的原型的测量数据进行比较，验证了该模型。源自检测器组件的散射的影响小于源自其他地方的影响。
Inelastic neutron scattering instruments require very low background; therefore the proper shielding for suppressing the scattered neutron background, both from elastic and inelastic scattering is essential. The detailed understanding of the background scattering sources is required for effective suppression. The Multi-Grid thermal neutron detector is an Ar/CO2 gas filled detector with a (B4C)-B-10 neutron converter coated on aluminium substrates. It is a large-area detector design that will equip inelastic neutron spectrometers at the European Spallation Source (ESS). To this end a parameterised Geant4 model is built for the Multi-Grid detector. This is the first time thermal neutron scattering background sources have been modelled in a detailed simulation of detector response. The model is validated via comparison with measured data of prototypes installed on the IN6 instrument at ILL and on the CNCS instrument at SNS. The effect of scattering originating in detector components is smaller than effects originating elsewhere.