ELECTRON-ION COINCIDENCE SPECTROSCOPY ON ATOMIC BARIUM IN THE EXCITATION RANGE OF THE 4D GIANT-RESONANCE

For the first time a free metal atom has been investigated by analyzed electron-ion coincidence spectroscopy after inner-shell excitation wi th synchrotron radiation. Probabilities of the decay from different Ba + inner-hole states (4d-1, 5s-1, 5p-1) to higher charged ions (Ba2+, B a3+, Ba4+ ) have been determined, which allows a direct link between e lectron and ion spectroscopy results. Comparison between the different data sets and Hartree-Fock calculations for N45 Auger transitions yie lds new knowledge about direct double ionization processes, e.g., thei r dominance on 4d-1 Auger decay.