The Method And Influencial Factors Of Hpge ? Spectrum Analysis On Natural Radiational Nuclides Contents In Geological Samples

With the increasing use of nuclear technology,radioactive analysis methods are more mature,in a number of analytical methods,? spectrometry analysis with a simple sample preparation,measurement time is short,cost-effective,accurate and at the same time Measurement of multiple radio nuclides and other advantages are widely used.Indoor HPGe ? spectrometry analysis of natural radionuclide content,is measured by natural radio nuclides or their series of emission of ?-ray characteristic peaks,to achieve geological samples of radio nuclides 238 U,226Ra,232 Th,40K qualitative and quantitative Explanation,is a more accurate analysis method.In this paper,the low-background HPGe ? spectrometer is used to measure the geological samples,and the ?-spectrum of the experiment is carried out.The key problems of spectral data processing(spectral smoothing,peak finding and peak Area,subtract the background and seek net peak area)for analysis and research,The area of natural radio nuclides 238 U,226Ra,232 Th and 40 K in geological samples were obtained by theoretical comparison and comparative method.The ? spectrum of the standard sample source was simulated by MCNP5 B program.The detection efficiency of the universal peak of the simulated sample was calculated.The specific activity of the natural radionuclide was calculated by comparing the calculated results with the calculated results.The deviation of the standard value,the relative deviation of less than 4%,verify the simulation is reliable.In view of the advantages of simple,time-saving and cost-saving in MCNP5 B program,the effects of matrix composition,high-energy gamma-ray Compton scattering and other factors on the content of 238 U were studied.The influence of sample content was analyzed by theoretical comparison Factor,for the accurate measurement of 238 U provides a reference.