Evidence for two-nucleon polarization in the π(hsub(9/2)isub(13/2))sub(11-)ν(j-2)sub(0+) level in 208Po

From in-beam gamma-ray spectroscopy measurements on the208Pb(α, 4n)208Po reaction using the Stockholm 225-cm cyclotron, we have concluded that there is an 11-, 8 ns isomeric state in208Po, which lies 1 175 keV above the π(h9/22)8+ state and that this isomeric state should have the configuration π(h9/2i13/2)11- ν(j-2)0+. Calculations based on the use of empirical two-particle interactions give a position of the 11-level which deviates by about + 100 keV from the experimentally found position. It is suggested that this deviation is mainly due to the difference in the polarization of the206Pb-and208Pb-cores by the two alignedh9/2andi13/2protons.