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

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 He7 and B7 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 Li7 and Be..