Collective-coupling analysis of spectra of mass-7 isobars:^{7} He,^{7} Li,^{7} Be, and^{7} B

Rhodes University, Grahamstad, Eastern Cape, South Africa
Physical Review C (Impact Factor: 3.88). 12/2006; 74(6). DOI: 10.1103/PhysRevC.74.064605
Source: arXiv

ABSTRACT A nucleon-nucleus interaction model has been applied to ascertain the underlying character of the negative-parity spectra of four isobars of mass-7, from neutron- to proton-emitter drip lines. With a single nuclear potential defined by a simple coupled-channel model, a multichannel algebraic scattering approach (MCAS) has been used to determine the bound and resonant spectra of the four nuclides, of which 7He and 7B are particle unstable. Incorporation of Pauli blocking into the model enables a description of all known spin-parity states of the mass-7 isobars. We have also obtained spectra of similar quality by using a large space no-core shell model. Additionally, we have studied 7Li and 7Be using a dicluster model. We have found a dicluster-model potential that can reproduce the lowest four states of the two nuclei, as well as the relevant low-energy elastic scattering cross sections. But, with this model, the rest of the energy spectra cannot be obtained.

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