[Background] Response spectrum of radiation sources can be extracted from airborne gamma-ray spectrum by the least square method, however, the analysis accuracy of artificial radioactivity information is affected by the accuracy of response spectrum of radiation sources. [Purpose] This study aims to improve accuracy of response spectrum of radiation sources by extracting artificial radioactivity information from airborne gamma-ray spectrum. [Methods] We obtained the linear law between peak intensity of annihilation radiation from cosmic gamma-rays and count rate of cosmic gamma-rays in the last channels by experiments at different detection altitudes and the response spectrum of cosmic gamma-rays by Monte Carlo (MC) simulation. Meanwhile, the response spectrum of radon daughters could be replaced by the response spectrum of stratum radiated from only 235U and 238U series, which was verified by experiments at eight detection altitudes. [Results] The above conclusions were applied to inverse activities of two point sources at different detection altitudes and locate radiation hotspot of artificial radioactivity nuclide. [Conclusion] These results show that the proposed approach can extract artificial radioactivity information better. And it provides a valid method to use airborne gamma-ray spectrometry in nuclear emergency.%最小二乘法的航空 γ 能谱解析可有效分离各辐射源的响应谱,基于此获得的人工核素响应谱可有效应用于地面人工核素定位与定量计算.本文针对以往研究的不足展开讨论,依据实验分析获得航空 γ 能谱中宇宙射线湮灭辐射强度与宇宙射线道计数成线性规律,并利用蒙特卡罗(Monte Carlo, MC)模拟获得航空γ谱仪对宇宙射线中湮灭辐射的响应谱;实验发现可运用"航空 γ 谱仪对平衡天然铀系地层的响应谱"替代"航空 γ谱仪对大气氡子体的响应谱".并将上述结论应用于静态点源活度反演实验及人工辐射热点定位,证实该方法能更准确地提取人工放射性信息,为核应急中航空γ能谱的有效应用提供参考.
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