On the orthogonality of initial and final states in (e,3e) and (γ,2e) collisions

We present a comparative study of multiple differential cross-sections in (e,3e) and (γ,2e) processes. We make use of initial states with different angular and radial electron-electron correlation factors in a perturbative model, and a C3 wave function to describe the final state. We also compute orthogonality factors between initial and final states. All the calculations show that a simple angular correlation can be used to achieve good qualitative as well as quantitative agreement with experimental results.