Lifetime of the K{sup {pi}}=8{sup -} isomer in the neutron-rich nucleus {sup 174}Er, and N=106 E1 systematics

Chopped-beam techniques and {gamma}-ray spectroscopy with Gammasphere have been used to measure the lifetime of the 1112-keV 8{sup -} isomeric state in {sup 174}Er. The value obtained of {tau} = 5.8(4) s corresponds to a reduced hindrance of f{sub {nu}} = 98 for the 163-keV E1 transition to the 8{sup +} state of the ground-state band, in good agreement with the systematics of the corresponding E1 strengths in the N = 106 isotones. The K-mixing in the 8{sup -} states is calculated in the context of the particle-rotor model and used to extract the underlying reduced hindrances.