Study of spectroscopic factors at NÂ =Â 29 using isobaric analogue resonances in inverse kinematics

Shell closures and their associated magic numbers of nucleons provide a unique means for studying the structure of exotic nuclei far from stability. An experiment was recently performed at the National Superconducting Cyclotron Laboratory to measure resonant elastic proton scattering on 46Ar in inverse kinematics in the region containing isobaric analogue states of 47Ar, an N=29 nucleus with one neutron above the N=28 shell closure. Four candidate resonances were observed: one corresponding to the 3/2− ground state of 47Ar, another corresponding to its 1/2− first excited state, and two that likely correspond to states in the 47K compound nucleus. The observed properties of the ground state resonance were compatible with values from the literature, but a significantly lower spectroscopic factor was found for the 1/2− state resonance.