Transient Fields in Ferromagnetic Iron and Gadolinium

Experiments studying the velocity dependence of the transient field for ${}_{}{}^{196}{}_{}{}^{}\mathrm{Pt}$ in Fe and the transient field for ${}_{}{}^{194,196,198}{}_{}{}^{}\mathrm{Pt}$ in Gd have been carried out in order to make comparisons with the recent Lindhard-Winther theory. Agreement between theory and experiment is good concerning the shape of the velocity dependence, but the experimental value is a factor of 2 larger than theoretically predicted. A large precession due to the transient field ($\phi =-51\mathrm{}\pm 7$ mrad) has been found for Pt in Gd. A transient field precession for Pd and Cd in Gd has been computed on the basis of recent radioactivity results. The internal field for Pt in Gd has been measured to be -780±120 kG, while former internal field values for Mo, Ru, and Hf in Gd have been corrected for transient field effects.