Multiple photoionization for 2p shells in Fe atom

Study of the single photoionization with subsequent radiative and Auger cascade includes all levels of the ground configuration. It is demonstrated that the quadruple photoionization dominates over other multiple-photoionization processes.

Analysis of the partial photoionization cross sections to configurations of the produced ions shows that the excited long-lived configurations accumulate the main population of the Fe^4+^ ion. The main decay branches of the radiative and Auger cascade following a creation of the 2p shell vacancy in the iron atom are identified. The ion yields for the photoionization and cascade obtained by considering level-to-level transitions are compared to the previous configuration average calculations.