摘要
在相同条件下，以不同时间辐照Au箔和Eu箔，用γ谱仪测量^(198)Au的411keVγ峰面积和^(152)Eu的411keVγ峰面积，再通过4πβ－γ符合装置测得金箔的绝对中子注量率，根据两者的峰面积之比和测得的Au箔绝对中子注量率，求得^(152)Eu的411keVγ峰面积对应的中子注量率。在待测中子场中，照射Au箔，利用γ谱仪测量其411keVγ峰面积和刻度过的^(152)Eu的411keVγ峰面积，根据两者之比和在已知中子场中求得的^(152)Eu的411keVγ峰面积对应的中子注量率，确定了待测中子场的中子注量率。该方法避免了不同γ谱仪对能量响应、探测效率和几何条件不同带来的误差。其测量结果与其它方法测量结果一致。
A method for thermal neutron flux measurement by γ spectrometer is introduced. The 411keV γ ray peak areas for both Au and Eu foils irradiated in a reference field were first measured by a γ-spectrometer. And the absolute neutron flux for the Au foil was determined by a 4πβ-γ counter Then the neutron flux corresponding to ^(152)Eu can be derived from the 152Eu to ^(198)Au peak area ratio and the above-mentioned absolute neutron flux for Au. For an unknown field, the 411keV peak area of an irradiated Au foil in the field was measured by another γ-spectrometer, which also measured the peak area of the 411keV γ rays from the ^(152)Eu foil irradiated in the reference field. Based on the ratio of these two peak areas and the aforsaid neutron flux for Eu in the reference field, the absolute neutron fiux of the unknown field could be determined.
出处
《核技术》
EI
CAS
CSCD
北大核心
2000年第7期479-482,共4页
Nuclear Techniques
