On the reversibility of stripping reactions

The basis for the equivalence of prior and post forms of the T-matrix in both the Born and the distorted wave Born approximations is here studied in a one-dimensional model that facilitates clarification of some of the underlying mechanism. One sees how important it is that changes in the wave functions bring it about that averages of different perturbing potentials over different regions can still be equal. The post form commonly employed for a (d, p) reaction makes it seem at first sight that the potential stripping the deuteron apart is the potential that holds it together. The prior form DWBA has as a perturbation the intuitively appealing interaction responsible for the classical break-up of the deuteron and contributing to the “surface reaction” nature of stripping.