Inner-shell photodetachment from Se⁻negative ions at the ALS

The photodetachment spectrum of Se− from 50 – 62 eV has been investigated using the merged ion-photon beam photodetachment technique. Se+ and Se++ ions formed by double and triple detachment were detected as a function of photon energy. Correlations in short-lived negative ion resonances formed by completely filling the valence 4p shell in Se- by photoexcitation of 3d electrons lead to three resonance structures. The resonances are observed in both the Se+ and Se++ decay channels bound by several eV below the 3d detachment threshold near 54 eV.