Note on the Lifetime of Metastable States

The available data on approximately forty $\gamma$-emitting metastable states of isomeric nuclei has been compared with the present theories. Nearly all of the points lie near two straight lines when $log\lambda$ (${\sec .\mathrm{}}^{-1\mathrm{}}$) is plotted against $logE$ (Mev). These lines fall close to the theoretical curves of Bethe calculated for electric $2^4$ and $2^5$ pole radiation.