The technique of invariant mass spectroscopy has been used to measure, for the first time, the ground state energy of neutron-unbound F28, determined to be a resonance in the F27+n continuum at 22 0(5 0)keV. States in F28 were populated by the reactions of a 62MeV/u Ne29 beam impinging on a 288mg/cm2 beryllium target. The measured F28 ground state energy is in good agreement with USDA/USDB shell model predictions, indicating that pf shell intruder configurations play only a small role in the ground state structure of F28 and establishing a low-Z boundary of the island of inversion for N=19 isotones.
ASJC Scopus subject areas
- Physics and Astronomy(all)