Bombardment of ${\mathrm{Pr}}^{141}$ targets with 75- to 137-MeV ${\mathrm{O}}^{16}$ ions has resulted in the identification of new alpha-emitting isotopes of holmium. The results obtained for the alpha-decay properties of these isotopes are: Excitation functions were obtained for the production of these nuclides and for the production of ${\mathrm{Dy}}^{150}$ ${\mathrm{Dy}}^{151}$, and ${\mathrm{Dy}}^{152}$. Large differences were observed for the energy dependence of the excitation functions of the isomer pairs which were attributed to angular momentum effects. Alpha branching ratios were estimated and used to calculate alpha reduced level widths.

• Received 10 December 1962

DOI:https://doi.org/10.1103/PhysRev.130.1491