Inner-shell photodetachment from Fe^{-} (original) (raw)

Inner-shell photodetachment from Fe − was studied in the 48-to 72-eV photon energy range using a merged ion-photon-beam technique. The absolute photodetachment cross sections of Fe − , leading to Fe + and Fe 2+ ion production, were measured. The 3p → (3d + εd) photoexcitation in Fe − negative ions gives rise to shape resonances. In the near-threshold region, shape-resonance profiles with l = 2 accurately fit the single-photodetachment cross section. Simultaneous double photodetachment was also observed, resulting in an increased Fe 2+ production which obeys a Wannier law. Despite the large number of possible terms resulting from the Fe − 3d open shell, a rough calculation using the R-matrix method qualitatively agrees well with the experimental data.