Shell-model calculations have been carried out for isospin-forbidden β-delayed proton emission for 1s-0d-shell nuclei. The process in which a nucleus near the proton drip line ${\mathrm{\beta }}^{+}$ decays by a superallowed transition to the isobaric analog state in the daughter nucleus is considered. The first complete set of calculations for the subsequent isospin-forbidden particle decay of the isobaric analog state is presented. The decay channels considered include the processes of single-proton, sequential two-proton, direct two-proton, and α decay. The calculations reproduce the known data and suggest further experiments.

• Received 20 August 1990

DOI:https://doi.org/10.1103/PhysRevLett.65.2753