%0 Generic %A M Heirwegh, C %A Pradler, I %A L Campbell, J %D 2013 %T Target origins, purity levels and PIXE analyses of trace elements %U https://iop.figshare.com/articles/dataset/_Target_origins_purity_levels_and_PIXE_analyses_of_trace_elements/1012793 %R 10.6084/m9.figshare.1012793.v1 %2 https://iop.figshare.com/ndownloader/files/1480616 %K PIXE analyses %K yield %K purity levels %K FFAST predictions %K XCOM attenuation coefficients %K oxide form %K light elements %K Hartree %K parameters computations %K light element absorbers %K kev %K National Institute %K Technology XCOM %K XCOM values %K trace elements %K Atomic Physics %K Molecular Physics %X

Table 2. Target origins, purity levels and PIXE analyses of trace elements.

Abstract

Proton-induced x-ray emission (PIXE) was used to assess the accuracy of the National Institute of Standards and Technology XCOM and FFAST photo-ionization cross-section databases in the low energy region (1–2 keV) for light elements. Characteristic x-ray yields generated in thick samples of Mg, Al and Si in elemental and oxide form, were compared to fundamental parameters computations of the expected x-ray yields; the database for this computation included XCOM attenuation coefficients. The resultant PIXE instrumental efficiency constant was found to differ by 4–6% between each element and its oxide. This discrepancy was traced to use of the XCOM Hartree–Slater photo-electric cross-sections. Substitution of the FFAST Hartree–Slater cross-sections reduced the effect. This suggests that for 1–2 keV x-rays in light element absorbers, the FFAST predictions of the photo-electric cross-sections are more accurate than the XCOM values.

%I IOP Publishing