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A New Analysis Principle for EDXRF: The Monte Carlo - Library Least-Squares Analysis Principle

Published online by Cambridge University Press:  06 March 2019

K. Verghese
Affiliation:
Center for Engineering Applications of Radioisotopes Box 7909, North Carolina State University Raleigh, North Carolina 27695-7909
M. Mickael
Affiliation:
Center for Engineering Applications of Radioisotopes Box 7909, North Carolina State University Raleigh, North Carolina 27695-7909
R.P. Gardner
Affiliation:
Center for Engineering Applications of Radioisotopes Box 7909, North Carolina State University Raleigh, North Carolina 27695-7909
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Abstract

A new analysis principle for energy-dispersive X–ray fluorescence has been identified and investigated as to feasibility. It consists of: (1) generating the complete spectral response for a sample of known (assumed) composition by Monte Carlo simulation,(2) keeping track of the individual elemental responses within the Monte Carlo simulation for use as library spectra, (3) use of the library least–squares (linear) analysis method to obtain the elemental amounts for any unknown sample spectrum, and (4) iterating these steps if the unknown amounts are too fax from the assumed composition originally used.

This principle has been investigated for a radioisotope source excited EDXRF system consisting of a 109Cd source and a Si(Li) detector for a Cu-Ni alloy sample (CDA Alloy 715) and a stainless steel sample (304 Stainless Steel) and found to give excellent results. This analysis principle makes unique use of the Monte Carlo “forward” simulation method to provide the elemental library spectra for use in the library least-squares method of analysis.

Type
VII. XRF Techniques, Instrumentation and Mathematical Models
Copyright
Copyright © International Centre for Diffraction Data 1987

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References

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