Photoionization of excited highly charged ions

We show that even for highly charged excited ions, not just for neutral excited atoms or low charged excited ions, autoionizing resonances connected with discrete inner‐shell excitations can lie close to (above or below) the photoionization threshold of the excited electron. This leads to a nonmonotonic dependence of the near‐threshold photoionization cross section on photon energy, as the location and shapes of these autoionizing resonances very strongly affect the behavior of the cross section.