NickelLIIIfluorescence and satellite transition probabilities determined with an alternative methodology for soft-x-ray emission spectrometry

Abstract

An accurate determination of the nickel ${L}_{\text{III}}$ x-ray transition probabilities was performed employing a wavelength-dispersive spectrometer (WDS) at the plane grating monochromator beamline for undulator radiation of the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute, at the electron storage ring BESSY II. An absolute calibration method developed for this spectrometer improves the reliability of the determination significantly because the calibration method does not require measurements of reference samples and provides a traceable uncertainty budget. The device was calibrated with respect to both its absolute detection efficiency and its response behavior. Therefore, a method to obtain the detection efficiency of a WDS in comparison to an absolutely calibrated energy-dispersive detector was successfully applied. In addition, response functions were developed and experimentally validated. The present results for the $\text{Ni}\text{ }{L}_{\text{III}}$ transition probabilities differ clearly from theoretical calculations and tabulated data found in the literature. Perspectives of a quantitative study of the interactions causing the satellite transitions are outlined and discussed in view of shake-off and Coster-Kronig processes.