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The electron spectra of xenon have been measured at the kinetic energy region of 8–40 eV using synchrotron radiation excitation below and above the 3d ionization threshold. The hole in the 3d orbital leads to the cascade of Auger transitions, the final steps of which give rise to pronounced satellite structures at the low kinetic energy region. In order to estimate the satellite production, the average kinetic energies and transition probabilities of Auger transitions after 3d ionization have been calculated using the method of global characteristics. Furthermore, the fine structure of the most intense satellite Auger transitions has been calculated using the pseudorelativistic Hartree–Fock method, and the results have been used to assign the main satellite peaks. In addition, the production of multi-charged Xe ions has been investigated and the role of electron–electron interaction in explaining the remaining differences between experiment and theory has also been discussed.

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The origin of the intense emission band at about 5 nm, dominating the emission spectra of tungsten ions in the ASDEX Upgrade tokamak and EBIT, is discussed. It is shown that the emission spectra of various ions calculated taking into account only the excitations from the ground level agree fairly well with the results obtained in the collisional-radiative model; thus, the contribution of the excitations from the other levels is small. Though the excitation spectrum for all sequence of ions W 29+ -W 37+ corresponds to the same transitions 4p 6 4d N → 4p 5 4d N+1 + 4p 6 4d N−1 4f, its energetic width essentially changes going on from the charge of ion q = 34 to q = 35. It is caused by the appearance of the excitations 4p 1/2 -4d 3/2 to the open 4d N 3/2 subshell, which are not quenched by configuration mixing. The satellite line at about 4.5 nm is explained by the transitions of the same type, although between configurations with one spectator 5s electron. The existence of one more group of intense lines in the region of 2 nm, corresponding to 5s-4p transitions, is predicted.