Neutron decay spectroscopy of neutron-rich oxygen isotopes

摘要

Neutron decay spectroscopy of neutron-rich oxygen isotopes has been performed using the two-proton knock-out reaction Be-9(N-26, X)O-24,O-23,O-22. A combination of the knock-out of valence and core protons can explain the three observed spectra. These knock-out processes are selective and preferentially populate hole states. The observed narrow resonance state in O-23 at an excitation energy of 2.8(1) MeV was assigned to the 5/2(+) state.