The lifetimes of states in two of the ΔI=1 bands in ${}_{}{}^{196}{}_{}{}^{}\mathrm{Pb}$ have been measured using the Doppler shift attenuation method, and a new ΔI=1 band has been observed in this nucleus. States in the bands were populated in the reaction ${}_{}{}^{107}{}_{}{}^{}\mathrm{Er}$${(}^{30}$Si,4n) at a beam energy of 142 MeV. Individual level lifetimes were extracted from the data by a analysis of the Doppler broadened γ-ray lineshapes. Under the assumption of pure M1 radiation, average reduced transition strengths B(M1)∼1.5 W.u. were obtained. The B(M1) values in both the ‘‘regular’’ and ‘‘irregular’’ bands exhibit similar dependence on spin. The neutron and proton configurations and nature of the collectivity in these bands is discussed.

• Received 9 September 1994

DOI:https://doi.org/10.1103/PhysRevC.51.115