Shell-model calculations for two-neutron transfer near the N=20 island of inversion

Abstract

We describe connections between shell-model calculation results and predictions for two-nucleon transfer reactions. Measurements of the ^{30}Mg(t,p)^{32}Mg reaction were used to identify a low-lying shape-coexisting 0^+ state in ^{32}Mg. Interpretations of those early, limited data were based on simple empirical models. The cross sections for two-nucleon transfer are, however, extremely sensitive to the details of the nuclear-structure. Motivated by the possibility of new high-resolution two-nucleon transfer measurements around the N=20 Island of Inversion, we have performed shell-model calculations wave functions for states in the nuclei ^{30,32}Mg using the SDPF-M and SDPF-MU interactions, and from those calculations obtain the two-nucleon transfer amplitudes that we use to predict cross sections for the ^{28,30}Mg(t,p)^{30,32}Mg reactions. The combined results show how the nuclear structure properties influence experimental observables for the (t,p) reaction. We compare our results with the existing data.