Auger cascade satellites following 3d ionization in xenon

Abstract

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.

Absolute cross sections for photoionization of Xeq +ions (1 ⩽ q ⩽ 5) at the 3d ionization threshold

“…This peak is not discernible in the other multiple ionization channels. It is noted that pathways after 3d photoionization of neutral Xe have been investigated in more detail by applying electron spectroscopy and coincidence techniques [1,[18][19][20][21][22][23].…”

“…The distribution of final charge states depends on the branching ratios for the various deexcitation processes. Comprehensive theoretical calculations for these quantities are cumbersome [1], nevertheless, they are required, e.g., for predicting the charge balance in astrophysical plasmas [2] or EUV-light sources [3]. Here, we report experimental absolute cross sections for multiple photoionization of Xe q+ ions with primary charge states 1 ≤ q ≤ 5 which were obtained by employing the photon-ion merged-beams technique at a synchrotron light source.…”

Investigation of the cascades in atoms using the global characteristics of spectra

“…The detailed calculations of the Auger transitions (51), (52) were carried out using the single-configuration pseudorelativistic Hartree-Fock method [98]. The calculated spectrum corresponds well to the experimental one and their comparison allows us to identify the main lines [32]. …”

“…Up to now such calculations even for the main part of the cascade are not numerous: in such a way the radiative decay of vacancies in subvalent shells of Kr [28], the Auger transitions following deep core ionization in Ar [29,30], the 3d 5/2 −5p excitation in Kr and 4d 5/2 − 6p in Xe [31], the 3d ionization in Xe [32] are studied.…”

“…In [36] the ion charge distribution due to vacancy cascades following the K, L 1 , L 2 , and L 3 shell ionization were calculated by the Monte Carlo method for the atomic numbers Z = 10−60. The Auger cascade spectra were mostly studied for Ar [13,29,30,[72][73][74][75][76][77]; also several works were devoted to Kr [31,73], Xe [31,32,78], Al [26], Ni [79], and Eu [66]. Because the X-ray transitions accompanying the cascade decay of inner-shell vacancies are less probable than the Auger transitions, the cascade affected emission spectra are less investigated, the results are mainly obtained for inert gases [27,33,[80][81][82][83][84] as well as for Fe [37], Ag [80], and Pb, Th, U [85].…”