Studies of one- and two-proton transfer in ¹²C,¹⁶O+¹⁵⁴Sm, and ¹⁶O+¹¹⁵In reactions

Abstract

Cross sections for quasielastic scattering and transfer reactions have been measured for ¹²C, ¹⁶O+¹⁵⁴Sm, and ¹⁶O+¹¹⁵In systems at energies above the Coulomb barrier. The transfer probabilities for one- and two-proton stripping reactions show an exponential decrease with increasing distance of closest approach for all the systems and the measured decay constants are found to be smaller than those derived from binding-energy considerations on the basis of the semiclassical model using a Coulomb trajectory. These results on the observed enhancement of transfer probabilities were further analyzed within the framework of the semiclassical model using two different formalisms: (1) considering the contribution of both Coulomb and nuclear branches of distance of closest approach to transfer probability and (2) in terms of the quantum diffractional effect in the broadening of the transfer angular distribution. It is seen that both these formalisms are able to offer a consistent explanation for the observed enhancement in the transfer probabilities and account for the "slope anomaly" seen in the transfer reactions in these systems.