DWBA-WM differential cross sections for positron impact ionization of H2

The calculation of Triple differential cross sections (TDCS) using the Distorted Wave Born Approximation (DWBA) with the Ward and Macek (WM) approximation to post collision interaction is performed for positron impact ionization of molecular hydrogen. The purpose of this study is to examine whether the DWBA-WM model produces better results compared to the more elaborate 3C model. We performed two investigations. First, the DWBA-WM study of the phenomenon of electron capture to the continuum where we found that the DWBA-WM produces better agreement with experimental measurement than the 3C model for 50 e V positron projectiles. However for 100 eV positron impact energies, no theoretical model predicts correctly the variation of the TDCS with ejected electron energies. The second investigation was on the variation of the TDCS with non-zero scattering angles. We found that DWBA-WM produces very similar results to the 3C model except at the recoil peak. Since no experimental results are available, we cannot conclude which of the two methods produces more reliable results.