Rules for Spin and Parity Assignments Based on<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="normal">Log</mml:mi><mml:mi>ft</mml:mi></mml:math>Values

Abstract

A survey was made of $log\mathrm{ft}$ values for forbidden $\ensuremath{\beta}$ transitions. Three cases, $^{90m}\mathrm{Y}$, $^{65}\mathrm{Ni}$, and $^{144}\mathrm{Pm}$ decays, were examined experimentally. A number of low $log\mathrm{ft}$ values reported in the literature are superseded by more recent larger values. Empirical rules for making spin and parity assignments from $log\mathrm{ft}$ values are proposed.