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The temperature dependence of the perturbed angular correlation of the 198-110 keV γ cascade in 169 Tm implanted in iron foil is consistent with a time-dependent magnetic interaction with a relaxation time constant τ S =2 ps.

It is demonstrated that the technique of perturbed angular correlations can be extended to the utilization of electrons. The sources were prepared by embedding 154 Eu into iron foil by means of an isotope separator. The perturbed angular correlation results for the 123 keV state in 154 Gd are consistent when obtained either by using the 1281 γ - 123 γ or the 1855 β - 123 γ cascade, for magnetization currents varying a factor of 15. The average ratio between the rotations of the correlation pattern is Δθ(β - γ)/Δθ(γ - γ) = 0.96 ± 0.10 where Δθ(γ - γ) = 0.105 ± 0.007. Identical perturbed angular correlation determinations are possible with conversion electrons in an energy range ≲ 20 keV. Further results indicate that the apparent rotations for Gd and Lu in iron are similar and follow the estimated magnetization of the foil. The Lu has an effective internal magnetic field of 483 ± 60 kG in unannealed iron foil.

The 1183 keV transition depopulating the 2+ beta-vibrational state in 178Hf was found to be E2 + M1 with (17 ± 10)% E2. The E2 branching ratios are shown to agree with theoretical predictions by Bohr and Mottelson.