A novel and holistic approach for experimental x-ray fundamental parameter determination—the Ru L-shell

Abstract

Abstract The present work aims to improve both the experimental and the data evaluation procedures necessary for a determination of L-subshell atomic fundamental parameters (FPs). The main motivation lies in the fact that the established approach, consisting of a sequential evaluation of recorded transmission and fluorescence spectra in the vicinity of the three L-absorption edges, provides relatively large uncertainties for the Coster–Kronig (CK) factors. Up to now, reliable uncertainty budgets were in the order of 15%–100% and more. The novel holistic evaluation procedure addresses these large uncertainties, by employing a much larger experimental dataset extending far above the L1 absorption edge and a combined evaluation approach for a more reliable determination of the CK factors. Here, using the Ru-L shells as an example, their uncertainties are reduced to under 15%. In addition, this enables also the determination of other relevant FP data, such as the L-subshell Auger yields, the L-subshell photoionization cross sections as well as the L-subshell fluorescence production cross sections with significantly lower uncertainties as compared to the established approach.