A novel method of selecting γ-ray transitions in heavy nuclei (A>100) at the proton drip-line has been attempted. The characteristic charged-particle radioactivity of these nuclei (alpha decay, ground-state proton decay, and β-delayed proton emission) has been used to tag γ-ray transitions recorded by the highly efficient Eurogam spectrometer. The ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$${+}^{54}$Fe and ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$${+}^{58}$Ni fusion-evaporation reactions, at a beam energy of 240 MeV, have been used to populate specific states of these neutron-deficient nuclei and results are presented for ${}_{}{}^{108,109}{}_{}{}^{}\mathrm{Te}$, ${}_{}{}^{109}{}_{}{}^{}\mathrm{I}$, and ${}_{}{}^{113}{}_{}{}^{}\mathrm{Xe}$, where γ-ray transitions have been identified. In the case of ${}_{}{}^{109}{}_{}{}^{}\mathrm{I}$, this represents the first observation of γ-rays from a ground-state proton emitter.

• Received 26 August 1994

DOI:https://doi.org/10.1103/PhysRevC.51.78