Nuclear Orientation and Reorientation Studies withNd147

Abstract

The results of new nuclear orientation measurements on ${\mathrm{Nd}}^{147}$ and reanalysis of old data in light of the revised temperature scale for neodymium ethylsulfate (NES) are presented. Previously assigned spins in ${\mathrm{Pm}}^{147}$ are confirmed, while several $\gamma$-ray mixing ratios are altered somewhat, and the previously reported $L=0\mathrm{}$ character of several $\beta$ branches is found to be incorrect. Auxiliary experiments in cerium magnesium nitrate (CMN) give further support to the new NES temperature scale. The attenuation factors of the 91-keV level in ${\mathrm{Pm}}^{147}$ were determined for the two lattices to be $G_2{\mathrm{}\left(91\right)\mathrm{}}_{\mathrm{NES}}=0.89\mathrm{}\pm 0.11$ and $G_2{\mathrm{}\left(91\right)\mathrm{}}_{\mathrm{CMN}}=0.42\mathrm{}\pm 0.12$. The latter is in poor agreement with Daniels and Misra's theoretical values. Available data on reorientation following decay of oriented nuclei in paramagnetic salts are summarized, and are interpreted as indicating dependences on both evironment and intermediate-state lifetime.