Experimental Studies of the Neutron-Deficient Gadolinium Isotopes. II.Gd145m

Abstract

The $N=81\mathrm{}$ isomer ${\mathrm{Gd}}^{145m}$ is characterized as having a half-life of 85 ± 3 sec and an $M4\mathrm{}$ isomeric transition of 721.4 ± 0.4 keV. It also has a direct $\frac{{\beta }^{+}}{\epsilon }$ branch to the $h_{\frac{11}{2}}$ state at 716.1 keV in ${\mathrm{Eu}}^{145}$. The intensity of this branch is 4.7% of the decay, implying a $log\mathrm{ft}$ of 6.2. The $M4\mathrm{}$ transition probability is calculated and compared with the trends among other isomeric transitions in this region.