Determination of X-ray excitation spectra in micro X-ray fluorescence spectrometry with capillary optics

R.D. PÉREZ; C..A. SOSA; V. SBARATO; J. J. LEANI; H. J. SÁNCHEZ

SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2016 vol. 117 p. 23 - 28

0584-8547

The quantitative X-ray fluorescence microanalysis by fundamental parameters requires the knowledge of the energydistribution of the excitation beam. When this beam is produced by capillary optics, its high intensity andanisotropy complicate a direct determination. An alternative is an indirect determination based on measurementof induced X-ray fluorescence in a set of targets. In this work the X-ray excitation spectrum is determined by aniterative deconvolution process of the fundamental parameter expression for the X-ray fluorescence intensities.Themethod has the advantage that it does not require any assumption about the energy distribution of the X-raysource or the energy dependence of the lens transmission.Numerous XRF targets of pure elementswith emissionlines covering the full energy range of the X-ray source are employed. The only requirement on the targets is ahigh homogeneity in its composition. In fact, it does not impose any condition on the sample thickness. The accuracyobserved in the validation process implemented with reference materials is similar to that reported withalternative approaches: 5% for main components, 10% for minor elements and 15% for trace elements