DECAY OF THE O-2+ STATE IN KR-80

The electric monopole strength rho2 for the 0(2)+ --> 0(1+) transition and the B(E2) value for the 02+ --> 2(1)+ transition were deduced from internal electron conversion and gamma-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 Kr-78, Kr-80, Kr-82 are compared to the predictions of the interacting boson model (IBM-2).