Hyperfine-Field Measurements on Sc in Fe and Re in Ni

The hyperfine fields ($H_{\mathrm{hf}}$) at ${}_{}{}^{44}{}_{}{}^{}\mathrm{Sc}$ nuclei in an iron matrix and at ${}_{}{}^{187}{}_{}{}^{}\mathrm{Re}$ nuclei in a nickel matrix are measured at room temperature using time differential perturbed ($\gamma -\gamma$) angular correlation technique (TDPAC). The values obtained are $H_{\mathrm{hf}}$ ${}_{}{}^{44}{}_{}{}^{}\mathrm{Sc}\mathrm{Fe} \left(300\mathrm{} {}_{}{}^{\circ }{}_{}{}^{}\mathrm{K}\right)=-94\mathrm{}\pm 3$ kOe and $H_{\mathrm{hf}}$ ${}_{}{}^{187}{}_{}{}^{}\mathrm{Re}\mathrm{Ni} \left(300\mathrm{} {}_{}{}^{\circ }{}_{}{}^{}\mathrm{K}\right)=-107\mathrm{}\pm 3$ kOe. An external magnetic field of a few kOe was applied to polarize the host matrices of iron and nickel. Using the same TDPAC technique, the magnetic moments of the 68-keV state in ${}_{}{}^{44}{}_{}{}^{}\mathrm{Sc}$ and of the 206-keV state in ${}_{}{}^{187}{}_{}{}^{}\mathrm{Re}$ are measured. The values obtained are $+(0.345\mathrm{}\pm 0.007){\mu }_N$ and $+(5.04\mathrm{}\pm 0.14){\mu }_N$, respectively. The measured hyperfine-field values are compared with the predictions of the existing models.