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A Versatile Fundamental Alphas Program for Use with Either Tube or Secondary Target Excitation

Published online by Cambridge University Press:  06 March 2019

L. Feng
Affiliation:
National Institute of Standards and Technology Gaithersburg, MD 20899
P. A. Pella
Affiliation:
National Institute of Standards and Technology Gaithersburg, MD 20899
B. J. Cross
Affiliation:
Kevex Instruments San Carlos, CA 94070-1308
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Extract

During this decade, several influence-coefficient algorithms have been published which utilize fundamental parameter equations to correct interelement effects in bulk samples. The Comprehensive Algorithm of Lachance (COLA) is one such algorithm and is used in the program NBSGSC(l). Another COLA-based computer program called FLY-FPM has been developed in China by one of the authors (L. Feng). Using FLY-FPM as a starting point, we developed a new COLA-based program as part of a Cooperative Research Agreement with Kevex Instruments. This program was designed for use with x-ray spectrometers that employ both tube and secondary targets for excitation. For direct tube excitation, the NIST tube spectral distribution algorithm is used in this program (2). For secondary target excitation, the radiation is usually treated as being monochromatic, and fundamental parameter expressions are formulated with this in mind.

Type
Research Article
Copyright
Copyright © International Centre for Diffraction Data 1989

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References

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