Gamma Transitions Following the Decay of Nickel-65

Abstract

The gamma transitions following the decay of 2.6-hour ${\mathrm{Ni}}^{65}$, have been studied by coincidence scintillation spectrometry. Gamma rays of energies 0.37, 0.51, 0.61, 0.77, 0.85, 0.95, 1.11, 1.48, 1.62, and 1.72 Mev having the intensity of 55, 1.5, 0.6, ∼1, ∼0.6, ∼0.3, 140, 290, 10, and 6 per thousand disintegrations, respectively, are emitted in this decay. The gamma-gamma coincidence study is consistent with energy levels of ${\mathrm{Cu}}^{65}$ at 0.77, 1.11, 1.48, 1.62, and 1.72 Mev. The angular correlation of 0.37- and 1.11-Mev gamma rays suggests the spin assignment of $\frac{5}{2}$ for the 1.11-Mev level and $\frac{7}{2}$ or $\frac{3}{2}$ for the 1.48-Mev level. Both the gamma transitions are mixtures of $E2\mathrm{}$ and $M1\mathrm{}$.