| The moon has a variety of mineral resources for human development, it's an important complement to the Earth's resources and reserves and has far-reaching impact on the sustainable development of human society. Detecting the distribution and relative content of U, Th, K, Fe, Ti, Al and some other useful elements on lunar surface using radioactive gamma spectrometry analysis and drawing the distribution of elements and material types on lunar surface are part of Chang'e 1 lunar probe satellite's scientific goals.Chang'e 1 satellite flied around the moon for about one year and the gamma-ray spectrometer on Chang'e 1 repeatedly fly over the moon in various regions. We can get the spectrum data to deal with through accumulation the detection data of each area.There are three sources of gamma rays on lunar surface: the lunar surface contains uranium, thorium, potassium and other natural decay of radioactive isotopes which directly release natural gamma-ray; the galactic cosmic rays (GCR) reacting with the elements on the lunar surface, which will occur Inelastic scattering and produce characteristics of gamma lines that not exist on earth; when elements on lunar capture and absorb low-energy neutron , it will release one or more kind of characteristics gamma-ray. The elements on lunar will release more gamma-ray than that of earth, Influenced by Inelastic scattering and neutron capture in the range of 30-3000KeV. For example, by GCR particles incident O can release characteristics gamma-ray of 6.129Mev, which not exists on earth. The energy of gamma-ray on lunar has a larger range than earth.We will compare existing field gamma-ray spectrometer when processing the data of gamma-ray return by Chang'e 1. There are the consequents of this paper: (1) Combined with field gamma-ray measurement principle, we analyzed the measurement method on lunar surface and the specific performance of measuring instruments.(2) Combined with gamma-ray emission mechanism and physical model on lunar surface, we studied characteristics of gamma-ray radiation of material on lunar surface and the relationship between material composition and gamma-ray spectroscopy.(3) On the analysis of pretreatment process on the three grade GRS data, we did initial processing of three grade data products, including smoothing by divided, removing background, peak search of single line and smoothing and removing backgrounds of total 1790 lines.(4) On the preliminary analysis of results level 3 data products, we proposed analysis model of relative content and did overall analysis of specific elements.In this paper we did pre-analytical processing based on existing gamma spectrometry data, which provide a good foundation for the later data processing and the Calculation of Exact content. Meanwhile, the results of relative content of elements provided scientific basis for moon landing and sampling.This paper is divided into the following six parts:(1) Introduction of the source of the topic, the research background, and status, etc. This part analyzed the purpose, contents, technical method of this research.(2) Introduction of gamma-ray source on the lunar surface, lunar gamma-ray measurement principle and the performance of measuring instruments.(3) Introduction of pretreatment process of scientific GRS data and elaboration of level 0 to level 2 data including data input, processing method and data output.(4) Part of GRS data processing of level 3,including source of level 3 data, smoothing of single line, removing background of single line, peak search of single line, smoothing of level 3 data, removing background of level 3 data.(5) This part described the content calculation of elements distribution, including line fitting, calculation of Characteristic peak area and relative distribution of elements.(6) Conclusion, including description and summary of gamma spectrometry analysis, and post-detection recommendations.
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