Gamma rays in ${\mathrm{Eu}}^{153}$ following the decay of ${\mathrm{Sm}}^{153}$ and ${\mathrm{Gd}}^{153}$ have been studied using coincidence and angular correlation methods. Results for the strong transitions are in agreement with the decay scheme given by McCutchen. Measurements were made of spectra of gamma rays in coincidence with the x-ray, 70-kev, and the 97-kev and 103-kev transitions in the decay of ${\mathrm{Gd}}^{153}$, and with eight energy regions in the decay of ${\mathrm{Sm}}^{153}$. A number of new, weak transitions were observed in the decay of ${\mathrm{Sm}}^{153}$, and a consistent decay scheme is proposed. Directional correlation measurements were made on the 70 kev-103 kev cascade from the decay of ${\mathrm{Sm}}^{153}$ and from the decay of ${\mathrm{Gd}}^{153}$. Possible spin assignments are discussed.

• Received 1 July 1960

DOI:https://doi.org/10.1103/PhysRev.120.1792