Importance of higher order coupling effects in sub-barrier fusion.

Abstract

Sub-barrier fusion has often been studied by linearizing couplings to nuclear structure for calculational convenience. Using a Green function technique and the interacting boson model, we are able to include couplings to all orders. After renormalizing the coupling strengths, we find that couplings to all orders lead to improved agreement with data for the fusion cross section and distribution of barriers, compared to the linear couplings.