Isomerism of Silver-108

A long-lived isomer of ${\mathrm{Ag}}^{108}$ has been detected in old ${\mathrm{Ag}}^{110m}$ samples. The isomer decays with a half-life ⋝ 5 years. Gamma- and beta-ray spectrometer data show that 90% of the disintegrations proceed by electron capture followed by a cascade of three gamma rays of 616-, 722-, and 434-kev energy, while 10% go by isomeric transition to ${\mathrm{Ag}}^{108}$. New values are given for the branching ratios of 2.4-minute ${\mathrm{Ag}}^{108}$.