Decay of the RadioisotopesGe68andGa68

Abstract

The decays of ${\mathrm{Ge}}^{68}$ (275 day) and ${\mathrm{Ga}}^{68}$ (68 minute) have been reinvestigated with single and coincidence scintillation spectrometers. Comparison of the gamma-ray singles spectra of the two radioisotopes indicates that ${\mathrm{Ge}}^{68}$ decays only to the ground state of ${\mathrm{Ga}}^{68}$ by electron capture. In addition to the known annihilation quanta and a gamma ray of 1.07 Mev in the decay of ${\mathrm{Ga}}^{68}$, gamma rays of 0.81±0.02, 1.24±0.02, and 1.88±0.02 Mev are observed. A level scheme of ${\mathrm{Zn}}^{68}$ with levels at 1.07, 1.88, and 2.31 Mev is proposed and is compared with level schemes of neighboring even-even nuclei.