Transition rates between negative-parity states in odd-mass gold nuclei

Abstract The half-lives of low-lying negative-parity states in 185 Au and 187 Au have been measured using mass-separated sources from the ISOCELE separator. The results, T 1 2 ( 9 2 − level at 8.9 keV in 185 Au ) = 4.8 ± 0.4 ns , T 1 2 ( 3 2 − level at 17.2 keV in 185 Au ) = 7 ± 2 ns , T 1 2 ( 7 2 − level at 107.4 keV in 185 Au ) = 0.37 ± 0.04 ns , T 1 2 ( 11 2 − level at 220 keV in 185 Au ) = 26 ± 2 ns , T 1 2 ( 5 2 − level at 171.8 keV in 187 Au ) = 1.1 ± 0.1 ns and T 1 2 ( 11 2 − level at 224 keV in 187 Au ) = 48 ± 2 ns , are discussed within the generalized particle-plus-asymmetric-rotor model, giving information on the structure of the states and on the nuclear-shape parameters.