The $g$ factor of the 4.49-MeV ($5^{-}$) state of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ has been measured in a time integral, external magnetic field, perturbed angular correlation experiment. A value of $g=0.54\mathrm{}\pm 0.10$ was obtained. The angular rotation of the $p^{\prime }-\gamma$ correlation for the 4.49-MeV ($5^{-}$) state was also measured for calcium nuclei implanted into a polarized iron foil. This measurement yields an average hyperfine magnetic field on calcium in iron which differs by a factor of 2 from the hyperfine field result obtained for ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ca}$ (3.19-MeV, $6^{+}$ state) implanted in iron. The discrepancy in observed fields indicates a multiplicity of lattice sites for this system. The theoretical estimate of the $5^{-}$ state $g$ factor is in agreement with the experimental value.

NUCLEAR MOMENTS ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}(p,p^{\prime }\gamma )$; measured $\mu$ ($5^{-}$, 4.49-MeV level) and $H_{\mathrm{hyp}}$ at Ca(Fe).

• Received 4 April 1974

DOI:https://doi.org/10.1103/PhysRevC.10.919