Measurements of the Magnetic Hyperfine Fields at Hg in Fe, Co, and Ni Hosts by thee−−γTime-Differential Perturbed-Angular-Correlation Method

The ${}_{}{}^{197m}{}_{}{}^{}\mathrm{Hg}$ radioactivity was implanted into pure-Fe, -Co, and -Ni hosts with the help of an isotope separator. These ferromagnetic hosts produce strong magnetic hyperfine interactions at the nuclear site of the Hg atoms. These hyperfine interactions were studied by time-differential measurements of the 165-keV $L$-conversion $e^{-}$-134-keV $\gamma$ angular correlation. Measurements with both nonmagnetized and magnetized foils were performed. By use of the quite accurately known g factor of the 134-keV state of ${}_{}{}^{197}{}_{}{}^{}\mathrm{Hg}$, the magnetic hyperfine fields $\left|H_{\mathrm{int}}\right|=692\mathrm{}\pm 55,483\pm 40, \mathrm{and} 103\pm 8$ kG for the Fe, Co, and Ni lattices, respectively, were deduced.