On Using Monte Carlo Generated Libraries for Applying the Library Least-Squares Analysis Approach to the C/O Tool

摘要

The traditional C/O tool has always had relatively low detection efficiency, poor resolution, and small signal-to-noise (S/N) ratio. The reasons for this are primarily that the detector diameters are limited in size by the necessary small tool diameters. To offset this problem the authors propose the use of the entire collected spectrum by using the Monte Carlo - Library Least-Squares (MCLLS) approach, which involves the generation of complete elemental libraries by Monte Carlo simulation. The specific purpose Monte Carlo code CEARCO has been developed and used for this purpose. The elemental library spectra for all elements that yield gamma rays in the C/O tool are generated by first using the Monte Carlo code CEARCO to generate the elemental library spectra incident on the detector. These library spectra are then used with unknown mixture C/O spectra to calculate the amounts of C, O, and other elemental amounts present by the LLS approach. It is estimated that this approach produces results with uncertainties between two and three times smaller than the use of the window approach that uses only peak intensities with the available data.