THE APPLICATION OF LaBr3(Ce) GAMMA RADIATION SCINTILLATION SPECTROMETER TO DIRECT DETERMINATION OF URANIUM CONTENT OF URANIUM ORE BODIES
WU Yong-peng1,2, TANG Bin2, CHENG Jian-ping1, LIANG Yong-shun2, WANG Zhe2
1. Department of Engineering Physics, Tsinghua University, Beijing 100084, China;
2. Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense, East China Institute of Technology, Nanchang 330013, China
Abstract:Lanthanum bromide scintillator, namely LaBr3(Ce), is a new detector which has excellent comprehensive performance for detecting gamma-ray. However, LaBr3(Ce) detector fails to measure the fine structure of gamma-ray spectrum from the uranium-bearing ore body for its limited energy resolution, and the spectrum measured doesn't show the characteristic peaks which are directly related to uranium content. Under such circumstances, the development of a technique which can determine uranium content directly is necessary. The authors measured a series of hard rock radionuclide-bearing ore bodies using a LaBr3(Ce) probe made in China, and determined uranium content directly by relative analysis combining energy window with linear regression based on 234Pam, 1.001 MeV characteristic energy and, as a result, obtained satisfactory results, which show that the relative error is less than 10.0% for uranium content over 99×10-6, and the error is less than 8.5% for other main radionuclides.
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