Observation of a p -wave one-neutron halo configuration in Mg 37

Abstract

Cross sections of 1n-removal reactions from the neutron-rich nucleus Mg37 on C and Pb targets and the parallel momentum distributions of the Mg37 residues from the C target have been measured at 240MeV/nucleon. A combined analysis of these distinct nuclear- and Coulomb-dominated reaction data shows that the Mg37 ground state has a small 1n separation energy of 0.22-0.09+0.12MeV and an appreciable p-wave neutron single-particle strength. These results confirm that Mg37 lies near the edge of the "island of inversion" and has a sizable p-wave neutron halo component, the heaviest such system identified to date. © 2014 American Physical Society.