The interaction of an E/A = 57.6-MeV Ne-17 beam with a Be target is used to populate levels in Ne-16 following neutron knockout reactions. The decay of 16Ne states into the three-body O-14 + p + p ...continuum is observed in the High Resolution Array (HiRA). For the first time for a 2p emitter, correlations between the momenta of the three decay products are measured with sufficient resolution and statistics to allow for an unambiguous demonstration of their dependence on the long-range nature of the Coulomb interaction. Contrary to previous measurements, our measured limit Gamma
A 13F resonance was observed following a charge-exchange reaction between a fast 13O beam and a 9Be target. The resonance was found in the invariant-mass distribution of 3p + 10C events and probably ...corresponds to a 5/2+ excited state. The ground state was also expected to be populated, but was not resolved from the background. The observed level decays via initial proton emissions to both the ground and first 2+ state of 12O , which subsequently undergo 2p decay. In addition, there may also be a significant proton decay branch to the second 2+ level in 12O . The wave function associated with the observed level may be collectivized due to coupling to the continuum as is it located just above the threshold for proton decay to the 2+2 state of 12O .
Transfer reactions have been used for many years to understand the shell structure of nuclei. Recent studies with rare-isotope beams extend this work and make it possible to probe the evolution of ...shell structure far beyond the valley of stability, requiring measurements in inverse kinematics. We present a novel technical approach to measurements in inverse kinematics, and apply this method to different transfer reactions, each of which probes different properties of light, neutron-rich nuclei.
Particle-decaying states of the light nuclei 11,12N and 12O were studied using the invariant-mass method. The decay energies and intrinsic widths of a number of states were measured, and the momentum ...correlations of three-body decaying states were considered. A second $2p$-decaying 2+ state of 12O was observed for the first time, and a higher-energy 12O state was observed in the 4$p$+2α decay channel. This 4$p$+2α channel also contains contributions from fissionlike decay paths, including 6Beg.s.+6Beg.s.. Analogs to these states in 12O were found in 12N in the 2$p$+ 10B and 2$p$+α+6Li channels. The momentum correlations for the prompt 2$p$ decay of 12Og.s. were found to be nearly identical to those of 16Neg.s., and the correlations for the new 2+ state were found to be consistent with sequential decay through excited states in 11N. The momentum correlations for the 2$^+_1$ state in 12O provide a new value for the 11N ground-state energy. Finally, the states in 12N/12O that belong to the A=12 isobaric sextet do not deviate from the quadratic isobaric multiplet mass equation form
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