The radiations of ${\mathrm{Ti}}^{51}$ (5.8 min) and ${\mathrm{Cr}}^{51}$ (27 day) have been investigated with beta- and gamma-scintillation spectrometers. Gamma rays having energies of 0.323, 0.605, and 0.928 Mev and relative intensities of 95.8:1.4:4.2, respectively, were observed to accompany the decay of ${\mathrm{Ti}}^{51}$. Two beta groups were observed of energy 2.13 and 1.5 Mev, having relative intensities of 94.4 and 5.6, respectively. The 2.13-Mev transition leads to the 0.323-Mev level of ${\mathrm{V}}^{51}$. There is no evidence for a beta transition to the ground state of ${\mathrm{V}}^{51}$. ${\mathrm{Cr}}^{51}$ decays by electron capture to both the ground state and the first excited state of ${\mathrm{V}}^{51}$. The intensity of the capture branch to the 0.323-Mev level was measured to be 9.8 percent. A value of 3.25×${10}^{-3\mathrm{}}$ was found for the total internal conversion coefficient of the 0.323-Mev gamma transition, indicating that the transition is $M1+E2\mathrm{}$. The spin and parity assignments suggested by the experimental data are discussed.

• Received 22 November 1954

DOI:https://doi.org/10.1103/PhysRev.97.1272