A semi-microscopic approach to transfer reactions

Abstract

We develop a semi-microscopic model to describe transfer reactions. For the sake of simplicity, we focus on nucleon-transfer reactions, but the theory can be generalized to other transfer processes. The model makes use of overlap integrals computed in the microscopic Resonating Group Method (RGM). This technique is based on an effective nucleon-nucleon interaction and on the cluster approximation. It avoids the choice of a nucleon-core potential for the residual nucleus, and does not require any fit of spectroscopic factors. The model is therefore free of parameter. For the entrance channel, we use the Continuum Discretized Coupled Channel (CDCC) method where the breakup of the projectile is simulated by approximations of the continuum. This technique is well known for elastic scattering and for breakup reactions. It is well adapted to weakly bound nuclei such as the deuteron. The model is applied to the \(^{14}\mathrm{C}(d,p)^{15}C\) and \(^{6}\mathrm{He}(d,n)^{7}Li\) reactions with RGM wave functions of \(^{15}\)C and of \(^7\)Li. The \(^{15}\)C nucleus is described by \(^{14}\mathrm{C}(0^+,2^+)+n\) configurations whereas \(^7\)Li contains the \(\alpha +t\), \(^{6}\mathrm{He}(0^+)+p\) and \(^{6}\mathrm{Li}(1^+,0^+)+n\) configurations. The spectroscopic factors are in fair agreement with the literature. We show that the model provides an excellent description of the transfer cross sections considering that no parameter is adjusted.