How to evaluate model2
-The cross section for ionization is given by an analytic expression which fits e + H(1s) -> e’ + H(2p) and which is an analytic function of Ip, the excitation energy. In this case Ip is a function of R and is the 1sg-2pu energy separation.
Long discussion about dielectronic resonances and electron energy in internal region and inelastic scattering from an ion!