Discrete structure in the 4d photoabsorption spectrum of tellurium and its ions

The 4d inner-shell absorption spectra of Te, Te+, Te2+ and Te3+ have been recorded with the dual laser produced plasma technique. Discrete structure due to 4d --> 5p transitions has been observed in the 37-45 eV region and identified using Hartree-Fock calculations within the superposition of configurations method. For comparisons of theoretical and experimental spectra, the method approximates a calculation of the resonant part of the photoionization cross section. It was also necessary, especially in the higher ion stages, to include absorption from excited states of the ground configurations. From these, synthetic spectra were produced which generally agree well with the experimental data.