Soft and Very Soft Fluorescence Analysis: Spectrographic and Electronic Modifications for Optimum, Automated Results
The use of soft X-ray sources (designed by B. L. Henke, Pomona College) in a commercial vacuum spectrograph requires modifications in the optic path dependent upon the wavelength region being considered. Changes of targets, tube and counter windows, primary and secondary collimators, and analyzing crystals in a Philips spectrograph will be described; these changes yield optimum results for quantitative analyses for elements oxygen through iron. Additional instrumental and electronic modifications will be discussed which increase analytical efficiency and provide automated output in the form of punch tape. With this equipment it is possible to use computer programs which perform the following functions: detect and correct for instrumental drift, compute and statistically evaluate calibrations, test standards for contamination, and test replicates of unknowns for precision. In these programs flexibility is emphasized so that details of analytical conditions and statistical tests can be altered to fit particular requirements. Plans of instrumental changes and Fortran II program listings are available from the authors.
KeywordsBackground Counting Rate Electronic Modification Counter Window Silicate Analysis Pomona College
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