【摘要】 嫦娥一号卫星伽玛射线谱仪(简称GRS)采用大面积碘化铯(CsI)探测器获取月球表面的特征伽玛射线,分析伽玛射线能谱可以反演月表的元素种类和相对含量.在嫦娥一号卫星环月探测期间,伽玛射线谱仪获取的流强除了来自月面的伽玛射线以外,主要部分来自于宇宙线持续轰击卫星材料产生的本底流强,而本底流强通常可以通过在奔月期间获取的巡航谱得到.遗憾的是嫦娥一号伽玛射线谱仪在奔月期间受到工程条件的制约并未获取到巡航谱,因而给数据处理带来了困难.针对0.55～2.75 MeV能段的伽玛射线能谱提出了一种方法用于估算本底的流强,并用嫦娥二号巡航谱的观测对该方法进行了检验,给出了初步的误差分析结果.更多还原

【Abstract】 The scientific objective of Chang’E-1 Gamma-ray spectrometer(GRS) is to study the element information including both type and abundance on the lunar surface by distinguishing the energy peak of gamma ray spectrum relative to the elements,and by calculating the peak area counts.Regretfully,the cislunar spectrum of GRS is not collected. Nevertheless,we propose a method to get the background count rate in the energy range of 0.55~2.75 MeV.The count rate map of natural radioactive elements in 2°×2°grids is shown after reducing the background count rate.The data of Chang’E-2 GRS is used to test the method,and the uncertainty of the result is discussed.更多还原