Comparison of different sources of background in XRF spectra of binary samples

M.C. VALENTINUZZI; H.J. SÁNCHEZ; JUAN JOSÉ LEANI

Análisis de materiales diversos por técnicas de rayos X

Editorial de la Benemérita Universidad Autónoma de Puebla (BUAP)

Lugar: Puebla; Año: 2012; p. 117 - 120

X-ray fluorescence spectra present singular characteristics produced by the different scattering processes. When atoms are irradiated with incident energy lower and close to an absorption edge, scattering peaks appear due to an inelastic process known as resonant Raman scattering. In this work we present theoretical calculations of the resonant Raman scattering contributions to the background of X-ray fluorescence spectra. In order to perform the calculations the Shiraiwa and Fujino´s model was used to calculate characteristic intensities and scattering interactions. This model makes certain assumptions and approximations to achieve the calculations, especially in the case of the geometrical conditions and the incident and take-off beams. The calculations show that the Raman scattering background is significant under the fluorescent peak, affects the symmetry of the peaks and, depending on the concentrations, overcomes the enhancements contributions (secondary fluorescence). The model proposed here allows analyzing the different sources of background, which contribute to a better understanding of the physical processes involved in the different techniques of XRF analysis.