Photoionization with excitation and double photoionization of two-electron atomic targets

We review recent theoretical results on the double photoionization and ionization with excitation of two-electron atomic targets obtained with the convergent close coupling (CCC) method. The method proved to be capable of producing accurate total ionization cross-sections for H^-, He, and Li⁺ in a wide photon energy range from the double ionization threshold to 10 keV where the results go over continuously to the non-relativistic limit of infinite photon energy. By applying scaling laws these results can be extrapolated to all two-electron systems with an arbitrary nucleus charge Z. Present theory can also describe accurately the angular correlation in the two-electron continuum in the form of the fully-resolved triple-differential cross-section (TDCS). The latest results for the TDCS on He agree very well with recent absolute measurements with linearly polarized light.