PCI in Electron-Atom Collisions

F we 8. Schematic potential curve diagram for the explanation of postcollision interaction in electron-atom collision. Decay at a distance R between scattered electron and excited atom will yield an electron energy e s,. Subsequently the system follows the Coulomb curve, yielding a kinetic energy -D for the scattered electron. Decay at smaller R will eventually lead to a trapping of the scattered electron. 

An advantage of the semiclassical description for such an analysis is the fact that only simple analytical expressions are involved which can easily be evaluated numerically without the need of much computer time. On the other hand, the semiclassical model is not the only one that yields a proper description of the PCI effects. King et developed the so-called 

The question of how far an interference between various autoionization amplitudes is possible has been analyzed in detail by Taulbjerg. He showed that transitions from states with different spin multiplicity do not interfere, whereas transitions from coherently excited states with different orbital angular momentum are expected to interfere. 

Other treatments of PCI have been given however, in these cases no comparisons with experimental results were performed. 

---