Deep sub-barrier fusion of p + ^6,7Li, p+D and S-function

The cross sections for the deep sub-barrier fusion reactions of light nuclei play important role in big-bang and stellar nucleosynthesis. This work calculates p+ ^6,7Li, p+D fusion cross sections within the theoretical framework of the selective resonant tunneling model. In this model, assumption of a complex square-well nuclear potential is invoked to describe the absorption inside the nuclear well. The theoretical estimates for these cross sections agree well with the experimentally measured values. The features of the astrophysical S-factor are derived in terms of this model