The electric monopole strength ${\mathrm{\rho }}^2$ for the $0_2^{+}$→$0_1^{+}$ transition and the B(E2) value for the $0_2^{+}$→$2_1^{+}$ transition were deduced from internal electron conversion and γ-ray spectroscopy and from the measurement of the lifetime of the $0_2^{+}$ state, performed by means of the Doppler shift attenuation method in gases. In addition, an upper limit was deduced for the E0 component of the $2_2^{+}$→$2_1^{+}$ transition. The available spectroscopic data on low-lying positive parity levels in ${}_{}{}^{78,80,82}{}_{}{}^{}\mathrm{Kr}$ are compared to the predictions of the interacting boson model (IBM-2).

• Received 8 September 1992

DOI:https://doi.org/10.1103/PhysRevC.47.521