Application of regularized probability absorber states to He++H+ collisions

Abstract

To improve on the behaviour of usual close coupling expansions at intermediate energies it has been recently proposed to enlarge the basis with the addition of probability absorbers or doorway states. Application to atomic expansions requires the regularization of the Coulomb potential interactions, either by using model potentials or projection techniques. A preliminary application of the latter method to the benchmark He+(1s)+H+ collisional system is presented, using a one-centre atomic expansion, in the range of 10-500 KeV impact energies. Use of different regularizations, together with an analysis on the shape of the probability absorber functions, permits electron loss, ionization, charge exchange and excitation cross sections to be obtained.