10.6084/m9.figshare.1012791.v1
C M Heirwegh
C
M Heirwegh
I Pradler
I
Pradler
J L Campbell
J
L Campbell
Interpolated Al mass attenuation coefficient values from XCOM and FFAST and experimental data of [47]
IOP Publishing
2013
Technology XCOM
parameters computations
FFAST predictions
kev
oxide form
light elements
Hartree
XCOM attenuation coefficients
XCOM values
light element absorbers
pixe
yield
National Institute
al
Atomic Physics
Molecular Physics
2013-09-06 00:00:00
Figure
https://iop.figshare.com/articles/figure/_Interpolated_Al_mass_attenuation_coefficient_values_from_XCOM_and_FFAST_and_experimental_data_of_a_/1012791
<p><strong>Figure 4.</strong> Interpolated Al mass attenuation coefficient values from XCOM and FFAST and experimental data of [<a href="http://iopscience.iop.org/0953-4075/46/18/185602/article#jpb474010bib47" target="_blank">47</a>].</p> <p><strong>Abstract</strong></p> <p>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.</p>