DECAY OF Au196m

Abstract

The isomeric state in Au¹⁹⁶ decays to the ground state with an initial M4 transition of energy 175.5 ± 0.5 kev, followed by 148.2 ± 0.5 kev and 188.8 ± 0.5 kev transitions in cascade; a transition of 85.0 ± 0.5 kev is probably also in cascade with these transitions. There is evidence of a weak 135.9 ± 0.5 kev transition converted in Pt, indicating a small electron capture branch in the decay. The half-life of the isomeric state is 9.5 ± 0.3 hours.