Abstract
The unbound nucleus has been investigated using invariant-mass spectroscopy following one-proton removal reaction from a beam at . The decay products, and two neutrons, were detected in coincidence using the newly commissioned SAMURAI spectrometer at the RIKEN Radioactive Isotope Beam Factory. The ground-state resonance was found to lie only above threshold. In addition, a higher lying level, which is most likely the first state, was observed for the first time at above threshold. Comparison with theoretical predictions suggests that three-nucleon forces, -shell intruder configurations, and the continuum are key elements to understanding the structure of the most neutron-rich oxygen isotopes beyond the drip line.
- Received 27 August 2015
DOI:https://doi.org/10.1103/PhysRevLett.116.102503
© 2016 American Physical Society