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

We have performed shell-model calculations of two-neutron amplitudes (TNA) relevant for the two-neutron transfer reactions ²⁸Mg(t,p)³⁰Mg and ³⁰Mg(t,p)³²Mg. The neutron-rich isotopes of Mg are central to the understanding of intruder configurations responsible for the “Island of Inversion” at N=20. Two-neutron transfer is a powerful tool to study these configurations. With new radioactive-beam facilities, new experiments are planned for similar work. In preparation for such new measurements, we have used the sdpf-mu interaction to calculate two-neutron amplitudes for states in ^30,32Mg. The calculations were performed using the code “KSHELL” [1] and ran on the High-Performance Computing Facility at the University of Connecticut. We have also used the TNA from these calculations in DWBA calculations to predict the relative cross sections for populating different states in ^30,32Mg via the (t,p) reaction. The results of the calculations, and the implications for future studies of two-neutron transfer in the Mg region will be discussed.

[1] N. Shimizu et al., Comp. Phys. Comm. 244, 372 (2019).