Formation and decay of Xe 4d-1 vacancies studied via electron-electron coincidence experiments

A versatile electron-impact spectrometer, equipped with three independent electrostatic analyzers, has allowed the simultaneous investigation of the excitation and ionization and Auger decay of the Xe 4d states via electron-electron coincidence experiments. Energy and angular dependence of the final-state continuum interactions, the postcollision interactions, has been studied in both the (e,e? Auger) and (e,2e) binding energy spectra up to 30 eV above the 4d thresholds. The experimental results have been compared with the theoretical predictions of Kuchiev and Sheinerman (Usp. Fiz. Nauk 158, 353 (1989) [Sov. Phys. Usp. 32, 569 (1989)]). A fairly good agreement between the experiments and theory has been found in all the studied cases. Also the decay of the Xe 4d-1np inner-shell excited states and the energy dependence of the 4d5/2:4d3/2 branching ratios have been studied and compared with analogous data from photoionization experiments.