NiLSelf-Absorption Spectrum

The shape and position of the Ni $L\alpha$ x-ray emission line ($\lambda =14.53\mathrm{}$ Å) has been studied as a function of bombarding electron energy ranging from 2 to 30 keV. The bombarding electrons struck the anode at normal incidence, and x rays were viewed by the spectrometer at a 90° takeoff angle. The Ni $L\alpha$ lines recorded under these conditions exhibit an increasing attenuation of intensity on the high-energy side and a shifting of the peak position towards lower energy with increasing bombarding electron energy. These changes are interpreted as due to differential self-absorption of the emission line in the anode. The emission measurements have been used to obtain the "$L$ self-absorption spectrum" of Ni, which agrees favorably with the absorption spectrum reported in the literature.